The present application is a divisional application of the chinese patent application entitled "front loading medical injector and syringe, syringe interface, syringe adapter and syringe plunger for use therewith," filed on 21/11/2000. The 200910128359.6 patent application is a divisional application of the invention patent applications filed by the applicant's medlar corporation under international application numbers PCT/US 00/31991, international application number 2000-11-21-2000, application number 00817905.0 at the national stage of entry, entitled "front loading medical injector and syringe, syringe interface, syringe adapter and syringe plunger for use therewith".
Drawings
Various embodiments of the present invention are described in conjunction with the drawings appended hereto, wherein:
FIG. 1 is a perspective view of the injector device of the present invention showing an injector housing and a syringe in a separated relationship;
FIG. 2 is an enlarged perspective view of the syringe of FIG. 1 attached to the front wall of the injector housing showing how a flange disposed at the rear end of the syringe prevents leaked fluid from entering the injector housing;
FIG. 3 is an enlarged cross-sectional view of the syringe shown in FIGS. 1 and 2, showing the configuration of the forward end of the syringe;
FIG. 4 is a perspective view of yet another embodiment of the present invention showing a syringe and a pressure sheath injector in a separated relationship;
FIG. 5 is a further perspective view of the embodiment shown in FIG. 4 showing a piston moved to a more forward position than the position shown in FIG. 4;
FIG. 6 is a cross-sectional view of the syringe and housing of FIGS. 1 and 2 showing the syringe securely connected to the front wall of the injector housing by a tab attached to the rear end of the syringe;
FIG. 7 is an enlarged cross-sectional view of the structure encircled by circle VII in FIG. 6 showing in greater detail the attachment of the syringe to the front wall of the injector housing;
FIG. 8 is an enlarged perspective view of the tab shown in FIG. 7 attached to the rear end of the syringe shown in FIG. 1;
FIG. 9 is an enlarged cross-sectional view of another embodiment of a tab attached at the rearward end of the syringe engaging the front wall of the injector, this view showing essentially the same structure shown in FIG. 7;
FIG. 10 is an enlarged perspective view of yet another embodiment of the syringe of the present invention showing at least one tab at the base of the syringe engaging a shoulder formed in the interface of the injector housing;
FIG. 11 is an enlarged perspective view of the syringe of FIG. 10 showing at least one tab from the rear end (or base side) of the syringe;
FIG. 12 is an enlarged perspective view of yet another embodiment of a syringe according to the principles of the present invention showing two tabs at the base of the syringe that engage the injector housing;
FIG. 13 is an enlarged perspective view of the syringe shown in FIG. 12 showing two tabs at the rear end of the syringe;
FIG. 14 is an enlarged perspective view of yet another embodiment of the syringe of the present invention showing more than two tabs at the base of the syringe engaging the injector housing;
FIG. 15 is an enlarged perspective view of the syringe shown in FIG. 14 showing the base end of the syringe having a plurality of tabs;
FIG. 16 is a partial, enlarged perspective view of another embodiment of the tab arrangement shown in FIGS. 1 and 8;
FIG. 17 is a cross-sectional view of the tab arrangement shown in FIG. 16 taken along line XVII-XVII;
FIG. 18 is a cross-sectional view of the syringe of FIGS. 14 and 15 having a portion of the front wall of the injector showing a shoulder securely engaged by the tabs at the base of the syringe and also showing a reciprocating collar disengaging the tabs from the shoulder;
FIG. 19 is a cross-sectional view of the embodiment shown in FIG. 18 showing the engagement shoulder to securely engage the syringe with the tabs of the injector housing;
FIG. 20 is a cross-sectional view of the embodiment of FIGS. 18 and 19 showing the engagement of the reciprocating collar with the tabs to disengage them from the shoulder of the injector housing;
fig. 21 is a cross-sectional view of an adapter assembly connected to the syringe shown in fig. 14 and 15;
FIG. 22 is a cross-sectional view of another embodiment of the adapter assembly shown in FIG. 21, the adapter including a tabbed opening for engagement with the injector housing;
FIG. 23 is a perspective view of the adapter and syringe shown in FIG. 22;
FIG. 24 is a further perspective view of the adapter and syringe shown in FIG. 22;
FIG. 25 is a cross-sectional view of an embodiment of the plunger and piston showing an electromagnetic mechanism that attracts the plunger and piston to each other during operation of the device in accordance with the principles of the present invention;
FIG. 26 is a partial cross-sectional view of yet another embodiment of the plunger and piston showing an electromechanical mechanism that releasably attaches the plunger and piston to one another during operation of the device;
FIG. 27 is an enlarged cross-sectional view of the piston and plunger shown in FIG. 26, showing the piston engaging the plunger;
FIG. 28 is a cross-sectional view of the piston and plunger combination of FIG. 27 taken along line XXVIII-XXVIII showing two projections extended to engage the piston with the plunger;
FIG. 29 is a cross-sectional view of the piston and plunger combination of FIGS. 26-28 having two protrusions that are retracted to allow the piston to be disengaged from the plunger;
FIG. 30 is an enlarged cross-sectional view of the plunger illustrating the placement of the pressure sensing device in the plunger in accordance with the principles of the present invention;
FIG. 31 is an enlarged cross-sectional view of the plunger shown in FIG. 30, showing the plunger subjected to fluid pressure contained in a syringe (not shown);
FIG. 32 is a side view of another embodiment of the present invention showing the addition of a tab to a syringe cap engaged with the end of the pressure jacket;
FIG. 33 is an enlarged cross-sectional view of another embodiment of the device shown in FIG. 7;
FIG. 34 is an enlarged cross-sectional view of another embodiment of the device shown in FIG. 33;
FIG. 35 is a side view of yet another embodiment of an apparatus for releasably interconnecting a plunger and a piston;
FIG. 36 is a side view of another embodiment of an apparatus for releasably interconnecting a plunger and a piston;
FIG. 37 is an end view of the separable member shown in FIG. 36;
FIG. 38 is a perspective cutaway view of a pressure jacket embodiment of the present invention showing a reciprocating collar disposed in the pressure jacket;
FIG. 39 is a cross-sectional view of the pressure jacket embodiment shown in FIG. 38 taken along line XXXIX-XXXIX;
fig. 40A is an exploded perspective view of yet another embodiment of a front-loading injector interface and injector system of the present invention;
FIG. 40B is a perspective view of the system shown in FIG. 40A in an installed position;
fig. 40C is a perspective view of the syringe interface shown in fig. 40A in an open position;
fig. 41A is an assembled perspective view of yet another embodiment of a front-loading injector interface and injector system of the present invention;
FIG. 41B is a perspective view of the system shown in FIG. 41A in an open position;
FIG. 41C is a front perspective view of the syringe interface shown in FIG. 41A in an open position;
FIG. 41D is a rear perspective view of the syringe interface shown in FIG. 41A in an open position;
fig. 42A is an assembled perspective view of another embodiment of the front-loading injector interface and injector system of fig. 41A-41D;
FIG. 42B is a perspective view of the system shown in FIG. 42A in a disengaged position;
fig. 42C is a front perspective view of the syringe interface shown in fig. 42A in a closed position;
fig. 42D is a plan perspective view of the syringe interface shown in fig. 42A in a closed position;
fig. 43A is an exploded perspective view of another embodiment of the front-loading injector interface and injector system of fig. 41A-41D;
fig. 43B is a perspective view of the syringe interface shown in fig. 43A in a closed position;
FIG. 43C is a side perspective view of the system shown in FIG. 43A in a first disengaged position;
FIG. 43D is a perspective view of the system shown in FIG. 43A in an installed position;
FIG. 43E is a perspective view of the system shown in FIG. 43A in a second disengaged position;
FIG. 43F is a perspective view of the system shown in FIG. 43A in an open position for removing the syringe;
FIG. 43G is an exploded perspective view of the system shown in FIG. 43A with the syringe interface in an open position;
FIG. 43H is a front perspective view of the syringe interface shown in FIG. 43A in an open position;
FIG. 43I is a rear perspective view of the syringe interface shown in FIG. 43A in an open position;
FIG. 44A is a perspective view of a slight variation of the version of the syringe interface shown in FIGS. 43A-43I in combination with or mounted on an injector head;
FIG. 44B is a rear perspective view of the syringe interface and injector head shown in FIG. 44A;
FIG. 45A is a perspective view of a slight variation of the second version of the syringe interface shown in FIGS. 43A-43I, in combination with or mounted on an injector head;
FIG. 45B is a rear perspective view of the syringe interface and injector head shown in FIG. 45A;
fig. 46A is an exploded perspective view of the first preferred embodiment of the front-loading injector interface and injector system of the present invention;
FIG. 46B is an assembled perspective view of the syringe interface shown in FIG. 46A;
FIG. 46C is a perspective view of the system shown in FIG. 46A in a disengaged position;
FIG. 46D is a perspective view of the system shown in FIG. 46A in an installed position;
fig. 47A is a perspective view of another embodiment of the first preferred embodiment of the front loading injector interface and injector system of fig. 46A-46D in an installed position;
FIG. 47B is a perspective view of the system shown in FIG. 47A in a disengaged position;
FIG. 47C is an exploded perspective view of the system shown in FIG. 47A;
FIG. 47D is an exploded perspective view of the syringe interface shown in FIG. 47A;
FIG. 47E is a partially assembled rear perspective view of the syringe interface shown in FIG. 47A;
FIG. 47F is an exploded rear perspective view of the syringe interface shown in FIG. 47A;
fig. 48A is an exploded perspective view of yet another embodiment of a front-loading injector interface and injector system of the present invention;
FIG. 48B is a perspective view of the system shown in FIG. 48A in a disengaged position;
FIG. 48C is a perspective view of the system shown in FIG. 48A in an installed position;
FIG. 49A is an assembled perspective view of yet another embodiment of the injector piston and syringe plunger interface system of the present invention;
FIG. 49B is an exploded perspective view of the piston/plunger system shown in FIG. 49A;
FIG. 49C is a perspective view of the piston/plunger system shown in FIG. 49B, with the plunger base separated from the plunger cover and associated with the piston;
FIG. 49D is a perspective view of the piston/plunger system shown in FIG. 49B having a plunger separated from the piston, the plunger including a plunger base and a plunger cover;
FIG. 49E is a rear perspective view of the piston/plunger system shown in FIG. 49A in a disengaged position;
FIG. 49F is an exploded perspective view of the plunger base and plunger cover shown in FIGS. 49C and 49D;
figure 50A is an exploded perspective view of yet another embodiment of the injector piston and plunger interface system of the syringe of the present invention;
FIG. 50B is an enlarged, partial cross-sectional view of the plunger base and piston shown in FIG. 50A in an engaged position;
figure 51A is an isolated perspective view of another embodiment of the injector piston and syringe plunger interface system shown in figures 50A and 50B;
FIG. 51B is a perspective view of the piston/plunger system shown in FIG. 51A, with the plunger base separated from the plunger cover and associated with the piston;
FIG. 51C is an enlarged, partial cross-sectional view of the plunger base and piston shown in FIG. 51A in an engaged position;
fig. 52A is an exploded perspective view of yet another embodiment of the injector piston and syringe plunger interface system of the present invention;
FIG. 52B is an exploded perspective view of the piston/plunger system shown in FIG. 52A;
FIG. 52C is a rear perspective view of the piston/plunger system shown in FIG. 52A in a disengaged position;
figure 53A is an exploded perspective view of another embodiment of the injector piston and syringe plunger interface system shown in figures 51A-51C and 52A-52C;
FIG. 53B is an enlarged perspective view of the piston/plunger system shown in FIG. 53A in a disengaged position;
FIG. 53C is a cross-sectional view of the piston/plunger system shown in FIG. 53A;
FIG. 53D is an exploded perspective view of the piston/plunger system shown in FIG. 53A;
FIG. 54A is a perspective view of a prior art syringe plunger;
FIG. 54B is an exploded perspective view of the plunger shown in FIG. 54A;
FIG. 54C is a perspective view of an embodiment of the syringe plunger of the present invention;
FIG. 54D is an exploded perspective view of the plunger shown in FIG. 54C;
FIG. 54E is a perspective view of yet another embodiment of the syringe plunger of the present invention;
FIG. 54F is an exploded perspective view of the syringe plunger shown in FIG. 54E;
FIG. 54G is a perspective view of yet another embodiment of the syringe plunger of the present invention;
FIG. 54H is an exploded perspective view of the syringe plunger shown in FIG. 54G;
FIG. 55 is a side elevational view of the second preferred embodiment of the front-loading syringe interface and syringe system of the present invention showing a release mechanism for attaching the syringe to the injector housing;
fig. 56 is an exploded, isometric, front elevation view of the syringe interface and syringe system of fig. 55;
FIG. 57 is an exploded, isometric rear perspective view of the syringe interface and syringe system of FIG. 56;
fig. 58 is an exploded, isometric rear perspective view of a portion of the syringe interface and syringe system illustrated in fig. 55-57;
FIG. 59 is an exploded, isometric rear perspective view of the syringe interface and further portion of the syringe system of FIGS. 55-57, showing in detail the rear portion of the flexible ring and a portion of the swivel ring of the interface/release mechanism;
FIG. 60 is an isometric rear view of the syringe interface and syringe system of FIGS. 55-59 showing the syringe in detail attached to the release mechanism;
FIG. 61 is an isolated, isometric, front elevational view of the portion of FIG. 59 showing in detail the forward portion of the rotating ring and a portion of its flexible ring, in accordance with the present invention;
FIG. 62 is a partial, isometric, front elevational view of the rear portion of the syringe of the second preferred embodiment of the present invention showing in detail the projection and flange configuration thereof;
FIG. 63 is a partial, isometric rear perspective view of the syringe shown in FIG. 62;
FIG. 64 is an isometric rear perspective view of the front plate of the release mechanism of the second preferred embodiment of the present invention;
FIG. 65 is an isometric front elevation view of the front plate shown in FIG. 64;
FIG. 66 is an isometric front elevation view of the flexible ring element of the release mechanism of the second preferred embodiment of the present invention, showing several aspects thereof in detail;
FIG. 67 is an isometric rear perspective view of the flexible ring shown in FIG. 66;
FIG. 68 is an isometric, front elevational view of the rotary ring element of the release mechanism of the second preferred embodiment of the present invention, which illustrates several aspects thereof in greater detail;
FIG. 69 is an isometric rear perspective view of the swivel ring shown in FIG. 68;
FIG. 70 is an isometric front elevation of the rear panel of the second preferred embodiment of the release mechanism of the present invention, showing several aspects thereof in detail;
FIG. 71 is an isometric rear perspective view of the rear plate illustrated in FIG. 70;
fig. 72 is an isometric front elevation view of the syringe interface and syringe system of the second preferred embodiment of the present invention;
FIG. 73 is an isometric rear perspective view of the syringe interface and syringe system of FIG. 72;
FIG. 74 is a cross-sectional view of a portion of the syringe interface/release mechanism of the second preferred embodiment of the present invention prior to insertion of the syringe into the interface/release mechanism;
FIG. 75 is a side cross-sectional view of the same components as shown in FIG. 74, with the syringe partially inserted into the interface/release mechanism;
FIG. 76 is a side cross-sectional view of the same features of the second preferred embodiment of the present invention shown in FIGS. 74 and 75, in this case illustrating the syringe after it has been fully inserted into the interface/release mechanism;
FIG. 77 is an end elevational cross-sectional view of the syringe and flexible ring element of the present invention as illustrated in FIG. 76, illustrating engagement of the syringe by the flexible ring;
FIG. 78 is an end sectional view of the syringe and flexible ring of the second preferred embodiment of the present invention, depicting the syringe disengaged from the flexible ring after a quarter turn;
FIG. 79 is a perspective view of a related art syringe illustrating the efficacy of a flange on the syringe for preventing contrast media from entering the injector housing;
figure 80 is an isometric front elevation view of a first preferred embodiment of the injector piston and syringe plunger interface system of the present invention;
FIG. 81 is an isometric rear perspective view of the piston/plunger assembly depicted in FIG. 80;
FIG. 82 is an exploded perspective view of the piston/plunger assembly depicted in FIGS. 80 and 81;
FIG. 83 is an exploded, isometric rear perspective view of the forward end of the first preferred embodiment of the piston/plunger assembly of the present invention;
FIG. 84 is an exploded perspective view of the same features of the piston/plunger assembly shown in FIG. 83, the assembly being viewed from a slightly different angle from the view shown in FIG. 83;
FIG. 85 is an isometric front view of a piston from the piston/plunger assembly shown in FIGS. 80-82;
FIG. 86 is an isometric side view of the piston shown in FIG. 85;
FIG. 87 is an isometric front view of the piston sleeve of the piston/plunger assembly shown in FIGS. 80-82;
FIG. 88 is a perspective view of a collar member of the piston/plunger assembly shown in FIGS. 80-82;
FIG. 89 is a further perspective view of the ferrule depicted in FIG. 88;
FIG. 90 is a third perspective view of the ferrule element depicted in FIG. 88;
FIG. 91 is an isometric end view of the clip spreader member of the first preferred embodiment of the piston/plunger assembly of the present invention;
FIG. 92 is a second perspective view of the clip spreader depicted in FIG. 91;
FIG. 93 is a third perspective view of the clip extender depicted in FIGS. 91 and 92;
FIG. 94 is a first perspective view of one of the trunnion ring clamps of the first preferred embodiment of the piston/plunger assembly of the present invention;
FIG. 95 is a second perspective view of the trunnion ring clamp shown in FIG. 94;
FIG. 96 is a further perspective view of the trunnion ring clamp shown in FIGS. 94 and 95;
FIG. 97 is a first perspective view of the plunger cover element of the first preferred embodiment of the piston/plunger assembly of the present invention;
fig. 98 is a second perspective view of the plunger cover shown in fig. 97;
fig. 99 is a further perspective view of the plunger cover shown in fig. 97 and 98;
fig. 100 is a fourth perspective view of the plunger cover element illustrated in fig. 97-99;
FIG. 101 is a first perspective view of the rubber cap support ring element of the first preferred embodiment of the piston/plunger assembly of the present invention;
FIG. 102 is a second perspective view of the rubber cap support ring element shown in FIG. 101;
FIG. 103 is a third perspective view of the rubber cap support ring element shown in FIGS. 101 and 102;
FIG. 104 is a fourth perspective view of the rubber cap backup ring element depicted in FIGS. 101-103;
FIG. 105 is an isometric side view of the rubber cap of the plunger of the first preferred embodiment of the piston/plunger assembly of the present invention;
FIG. 106 is a second perspective view of the rubber cover shown in FIG. 105;
FIG. 107 is a side elevational view of a portion of the first preferred embodiment of the piston/plunger assembly of the present invention showing the interrelationship of the piston, collar, clip stretcher, support ring clip and plunger cap thereof, showing the relationship of these components at rest or as the piston moves toward the front end of the syringe;
FIG. 108 is a side view of the portion of the piston/plunger assembly depicted in FIG. 107, in this case illustrating the relationship of the piston, collar, clip extender, backup ring clip and plunger cap thereof as the piston moves/retracts toward the rearward end of the syringe;
FIG. 109 is a side view of the piston/plunger assembly and a portion of the syringe showing the syringe, rubber cap, backup ring clamp and rubber cap backup ring relationship as the piston moves/retracts toward the rear end of the syringe and the backup ring clamp engages the rubber cap backup ring;
FIG. 110 is a perspective view of another embodiment of a rubber cap for use with the plunger of the present invention;
FIG. 111 is a side view of the rubber cover shown in FIG. 110;
FIG. 112 is a top view of the rubber cap shown in FIG. 110;
FIG. 113 is a cross-sectional view of the rubber cap shown in FIG. 110;
FIG. 114 is an exploded perspective view of another embodiment of the syringe interface/release mechanism of the present invention;
FIG. 115 is an end view of yet another embodiment of the syringe interface/release mechanism of the present invention;
FIG. 116 is a cross-sectional view of the end of a second preferred embodiment of the syringe of the present invention;
FIG. 117 is a cross-sectional view of another embodiment of the syringe shown in FIG. 116;
FIG. 118 is a schematic view of three embodiments of the slots provided in the rotating ring of the second preferred embodiment of the syringe interface/release mechanism of the present invention;
FIG. 119 is an exploded perspective view of yet another embodiment of a syringe interface/release mechanism in accordance with the principles of the present invention;
FIG. 120 is an exploded perspective view of yet another embodiment of a syringe interface/release mechanism in accordance with the principles of the present invention;
FIG. 121 is a front elevational view of yet another embodiment of a syringe interface/release mechanism in accordance with the principles of the present invention; and
fig. 122 is a side view of the syringe interface/release mechanism of fig. 121.
Detailed Description
Fig. 1 discloses an injector device 10 of the general type disclosed in U.S. patent No.5,383,858 for injecting liquid contrast media into the vascular system of an animal. The injector device 10 has a front-loading configuration. The device of fig. 1 employs a syringe 12 which may be loaded from the front end into the mounting assembly 14 associated with the front wall 16 of the housing 18 of the injector 20 by a first releasable mechanism 22. Syringe 12 may function as an injection procedure without the use of a pressure jacket (although the syringe may be used in an injector having a pressure jacket as described in more detail below in connection with fig. 4 and 5). To the extent consistent with this disclosure, the disclosure of the' 858 patent, which is assigned to Medrd, Inc., the assignee of the present application, is incorporated herein by reference.
Referring to fig. 1 and first releasable mechanism 22, mounting assembly 14 is provided with a generally cylindrical hub 26 which is adapted to receive the rearward end of syringe 12. The interface 26 includes an annular surface 28, which may be cylindrical or conical. As best shown in fig. 6 and 7, the annular surface 28 includes a distal shoulder 29 that engages a tab 30 on the rearward end of the syringe 12. The syringe 12 is inserted into the cylindrical port 26 until the tabs 30 engage the shoulder 29 to secure the syringe 12 to the injector 20.
Wherein the tabs 30 distribute the attachment force of the syringe 12 to the shoulder 29 evenly around the syringe. This will help maintain the connection between the syringe 12 and the shoulder 29 even if the syringe 12 deforms or "ovalizes" under pressure during use. This would overcome the potential inadequacies of the conventional front-loading injector system, which would not work if the syringe became oval under pressure during use.
Referring again to fig. 1, the syringe 12 includes an elongate tubular body or cannula 32 and a coaxial discharge injection portion 34 interconnected by an intermediate conical portion 36. A plunger 38 is slidably positioned within tubular body 32 and may be connected to a second releasable mechanism 40 on a piston 42 in injector housing 18. As will be explained in greater detail below, second releasable mechanism 40 is formed in part by plunger 38 and in part by piston 42.
The piston 42 and plunger 38 cooperate to eject fluid contained in the syringe 12 in a desired amount and at a desired rate. The second releasable mechanism 40 is designed to facilitate axial movement of the plunger 38 in both directions upon actuation. Second releasable mechanism 40 may also be designed to engage or disengage plunger 39 with piston 42, regardless of the position of plunger 38 within tubular body 32. Further, in this connection, the plunger 38 is reciprocated within the syringe tubular body 32 by an actuating mechanism that includes a piston 42 or a reciprocable drive member. While reciprocating, there is no need to allow the drive member or piston 42 to rotate.
Referring to fig. 1, to install a syringe, a syringe 32 is inserted into the hub 26 in the mounting assembly 14. As best shown in fig. 6 and 7, the tabs 30 initially move over the annular surface 28 where they engage the shoulder 29, thereby securely retaining the syringe 12 on the mounting assembly 14. As best shown in fig. 2 and 7, the mounting assembly 14 also includes a forwardly projecting annular ring or collar 44 which functions to ensure vertical engagement between the plunger 38 and the piston 42. As explained above, the forwardly projecting annular ring or collar 44 also acts as a seal between a flange 46 on the syringe 32 and the mounting assembly 14.
An elastic annular sealing flange 46 surrounds the tubular body 32 of the syringe 12 and is arranged at a predetermined distance forward of the tabs 30, which is substantially equal to the width of the annular surface 28. Thus, when the syringe 12 is inserted into the hub 26 in the mounting assembly 14 until the sealing flange 46 engages the annular ring 44, the annular ring 44 and the flange 46 form a seal between the syringe 12 and the mounting assembly 14.
The above described mounting arrangement has a number of advantages. Attachment of the tab 30 to the rear periphery of the syringe 12 during an injection procedure can minimize wobble of the syringe 12. The tabs 30 also allow the syringe 12 to rotate freely within the hub 26 while minimizing wobble. The tabs 30 also prevent the syringe 12 from being removed from the injector 20. The seal between the annular ring 44 and the flange 46 may also prevent contrast media spilled from the discharge end 34 of the syringe 12 from flowing into the injector housing 18 (as shown in fig. 2) and eliminate the need to construct corresponding components to be overly tight in tolerance. To enhance the sealing capability between the flange 46 and the annular ring 44, a suitable O-ring (not shown) may optionally be provided gog therebetween.
Referring to fig. 1, the device also includes a system that can be used to communicate syringe information from the syringe 12 to the injector controller 51. The syringe 12 has a coding means 48 located on the front of the tab 30 and behind the flange 46. The encoding device 48 may be a bar code or any other suitable encoding device known to those skilled in the art. When the syringe 12 is attached to the mounting assembly 14, a sensor 50 is provided in the annular surface 28 to read the coding means 48 if the syringe 12 is rotated after the tabs 30 engage the shoulder 29. The sensor 50 then sends the relevant signal to the injector controller 51, which interprets the signal and modifies the function of the injector 20 accordingly. Examples of information that may be encoded on the encoding device 48 include the size of the syringe 12, the volume of the syringe 12, the object contained in the syringe 12 (in the case of a pre-filled syringe), manufacturing information such as lot number, date and tool cavity (tool cavity) number, recommended contrast agent flow rate and pressure, and loading/injection sequence.
As an alternative to the bar code encoding device 48, the encoding device 48 may also include a machine readable convex or concave surface. The convex or concave surface is then read by an injector sensor 50 mounted in the annular surface 28 in a manner similar to reading a bar code. In addition to the encoding device 48, a mechanically readable device (e.g., a slot, hole, or protrusion on the syringe 12 or plunger 38) may be used to record the transition on the mounting assembly 14. Alternatively, optically readable means (e.g., characters, dots, and other geometric shapes) may be used to transmit information relating to the type of syringe used by the smart circuitry of the injector 20.
In fig. 1, the syringe 12 may be made of a clear PET polyester material, since the syringe 12 used in this embodiment does not have a pressure jacket for enhancing and viewing the contents of the syringe 12. In another version, the wall of the syringe 12 is made of polypropylene, which may be reinforced by providing a series of longitudinally spaced annular ribs on the tubular body 32 of the syringe 12. ("fig. 5 of the' 858 patent shows this configuration). As discussed in the' 858 patent, the ribs also serve a dual function for volume grading by appropriately spacing the ribs along the length of the tubular body 32 (e.g., in equal increments) for the purpose of indicating the amount of contrast media in the injector 12.
Referring to fig. 1 and 2, the tubular body 32 of the injector 12 is also provided with an indicator mechanism 52 that may be used to facilitate detection of the presence or absence of liquid contrast media in the injector 12. In this case, the detection mechanism 52 comprises a plurality of textured dots integrally molded on the syringe 12 that will provide a visual indication whether the syringe contains liquid or air. More specifically, the dots 52 are elliptical when air is observed as a background, but the dots 52 are circular when a liquid contrast agent having a different refractive index from air is observed as a background. Details of the indicating mechanism 52 are described in detail in U.S. patent No.4,452,251, assigned to Medrad, inc. To the extent consistent with this disclosure, the contents of U.S. patent 4,452,251 are incorporated herein by reference.
Fig. 3 shows the internal structure of the syringe discharge end 34. In particular, while the rear portion 54 of the discharge end 34 is of a tapered conical configuration, the forward connector portion 56 is of a generally cylindrical configuration and is formed with internal threads 58 for attaching a connecting tube to the discharge end 34. In addition, a reduced diameter nozzle 60 is disposed in the threaded cylindrical connector portion 56 and is integrally molded with the tapered rear portion 54 of the discharge end 34 near the location where the tapered and cylindrical portions are merged together.
Fig. 4 and 5 illustrate another embodiment of the invention in which the front-loading syringe 112 is mounted on the front of a pressure jacket 170, preferably made of a strong clear plastic such as polycarbonate. The pressure jacket 170 is in the form of an elongated tubular member whose rear end is suitably mounted in the mounting assembly 124 on the housing front wall 116 by fitting the flange of the pressure jacket 170 into a ferrule on the mounting assembly 124. The pressure jacket 170 also has an open front end 172 that can be used to receive the syringe 112.
In this embodiment, the pressure jacket 170 has an annular surface 174 adjacent the open front end 172, the annular surface 174 having a distal shoulder 175. The annular surface 174 is similar in construction to the annular surface 28 of the embodiment shown in fig. 1 and 7. Similarly, the tubular body 132 of the syringe 112 includes a tab 180 located near its forward end that engages the shoulder 175 when the tubular body 132 is inserted into the pressure jacket 170.
In addition, a pair of reinforced annular handles 162 are located on opposite sides of the forward, discharge end 134 of the syringe 112 to facilitate operation of the syringe 112, the handles being integrally molded with the discharge end 134 and the conical middle portion 136. In other respects, although not specifically disclosed and described, it is understood that various other features of the embodiments of the present invention disclosed in FIGS. 1-3, 6 and 7 may be optionally incorporated into the embodiments of FIGS. 4 and 5.
In use, the syringe 112 of fig. 4 and 5 may be installed in the pressure jacket 170 with the plunger 142 of the injector 120 in the retracted position shown in fig. 4, or in the advanced position shown in fig. 5. For example, as shown in FIG. 4, the piston 142 is in a retracted position and the plunger 138 is disposed at the rearward end of the syringe 112. The syringe 112 is then inserted into the open end 172 of the forward end of the pressure jacket 170 until the second releasable mechanism 140 engages the plunger 138.
In fig. 5, the piston 142 is in the forward position, and loading of the syringe 112 into the pressure jacket 170 is the same as that shown in fig. 4, except that the plunger 138 is also in the forward position in the syringe 112. Otherwise, the loading of the syringe 112 on the pressure jacket 170 is substantially the same as the process previously described in connection with fig. 4. However, having the syringe plunger 138 and piston 142 in their forward position, as shown in FIG. 5, has some advantages over the rearward position configuration of FIG. 4. For example, because the syringe plunger 138 and piston 142 are already in their forward positions, there is no need to move them forward in order to drive air out of the syringe 112 in preparation for a syringe filling operation. Instead, the plunger 138 and piston 142 may be caused to retract immediately to draw fluid into the syringe 112. Similarly, additional time may be saved by not retracting the plunger 138 and piston 142 after an injection operation is completed in preparation for the next injection operation.
In summary, a new and improved system has been disclosed by which a syringe, such as the syringe 12 of the embodiment of fig. 1-3, may be conveniently attached to and/or detached from the injector housing 18. To accomplish this, the first and second releasable mechanisms 22, 40 are cooperative to simultaneously and/or independently establish their respective connections and disconnections, with the first releasable mechanism allowing the syringe 12 to be attached to and detached from the injector housing 18, and with the second releasable mechanism allowing the plunger 38 of the syringe 12 to be drivingly connected to and disconnected from the piston 42 of the injector 20. Yet another advantage is that the plunger 38 may be placed in a driven or undriven state at any point along its path, thereby disengaging the syringe 12 from the injector 20, and without the need to retract the piston 42 or first disengage the syringe 12 from the patient undergoing injection before the piston 42 retracts.
Other desirable features of the present invention include the configuration of first releasable mechanism 22, which advantageously mounts syringe 12 to injector housing 18 with a secure fit from the standpoint of minimizing rattling and disengagement of the syringe during injection operations and eliminating the need for over-tightening manufacturing tolerances. It may also be advantageous from the standpoint of providing "custom programming" of the injector 20 for the encoding device 48 on the syringe 12 to cooperate with the sensor 50 on the injector 20. The elimination of the pressure jacket is also desirable from the standpoint of optimal visibility of the objects contained by the injector 12, optimal heat transfer to the objects contained by the injector, and reduced cleaning and maintenance required due to, for example, contrast media damage and contamination of the pressure jacket.
To eliminate the need for a pressure jacket, the syringe 12 may also be made of a relatively strong transparent plastic, or provided with annular stiffening ribs (not shown) that may be spaced to function as volume graduations. In addition, the presence of air in the syringe 12 may be readily detected using the indicator mechanism 52 of fig. 1 and 2, which is molded into the syringe tubular body 32 in the form of dots 52. The dots 52 are shown as oval or circular, respectively, depending on whether the tubular body contains air or liquid. In addition to functioning as part of the first releasable mechanism 22 for the syringe 12, the syringe resilient annular flange 46 cooperates with the annular ring 44, as shown in FIG. 2, to form a seal that prevents contrast media escaping from the injection end of the syringe 12 from flowing into the injector 20. The embodiment of the present invention shown in fig. 4 and 5 provides a system that has a number of other advantages, including time savings for syringe filling and syringe replacement operations, which may be achieved with a pressure jacket, such as the pressure jacket 170 mounted on the front wall 116 of the injector housing.
Fig. 6 shows a cross-sectional view of the syringe 12 after it is inserted into the injector 20 such that the tabs 30 engage the shoulder 29. The tab 30 is preferably a generally V-shaped member that preferably forms a loop around the rear end of the tubular body 32. Alternatively, one or more tabs are separately disposed around the rear end of the body 32. Each tab 30 on the loop has a first end 62 and a second end 64 (fig. 8 shows an enlarged perspective view of the loop of the tab 30). As shown in fig. 8, when the syringe 12 is inserted into the hub 26 of the injector 20, the first end 62 of the tab 30 engages the shoulder 29. A gap 66 around the periphery of tubular body 32 separates first ends 62 of tabs 30 from one another so that they are flexible and can be easily compressed. The second end 64 of the tab 30, on the other hand, forms a loop that is attached to the tubular body 32.
Thus, the syringe 12 may be conveniently connected to the injector 20 by simply inserting the rearward end of the tubular body 32 into the cylindrical hub 26. During insertion of the tubular body 32 into the cylindrical interface 26, the annular surface 28 compresses the first end 62 of the tab 30 until the first tab 62 clears the shoulder 29. Once the first ends 62 clear the shoulders 29, they will resiliently open and engage the shoulders 29 to prevent removal of the tubular body 32 from the hub 26.
The syringe 12 may be removed from the housing 20 using a reciprocating collar 68 that is disposed in the injector 20 behind the syringe 12 (once inserted into the cylindrical hub 26). The reciprocating collar 68 is preferably a cylindrical member that is movable in forward and rearward directions, as indicated by the arrows in FIG. 7. During an injection operation, the reciprocating collar 68 is in a rest position behind the tabs 30 such that the first end 62 remains engaged with the shoulder 29. To remove the syringe 12 from the hub 26 upon completion of an injection procedure, the reciprocating collar 68 is pushed toward the shoulder 29 by an actuating mechanism (not shown) or manually so that it compresses the first ends 62 so that they can be conveniently slid out from behind the shoulder 29. The syringe 12 may then be conveniently removed from the injector 20.
Alternatively, the tab 30 may be disengaged from the shoulder 29 by contracting the annular surface 28 in the direction of arrow 1100 in fig. 33. To accomplish this, annular surface 28 is made up of a plurality of segments 1102, all of which are retractable to release syringe 32. In yet another alternative embodiment shown in fig. 34, a portion of the inner surface 1104 is moved inwardly in the direction indicated by arrow 1106 to collapse the tabs 30 to cause the syringe 32 to disengage the shoulder 29. Other embodiments of these two configurations will be readily appreciated by those skilled in the art.
In the event that the syringe 112 is to be inserted into the pressure jacket 170 (as shown in fig. 4 and 5), the tabs 180 serve the same function as the tabs 30, except of course that they are positioned toward the front end of the syringe 112. In fact, it is contemplated that the tabs 180 of the present invention have the same configuration as the tabs 30, except for the positioning of the tabs 180 on the tubular body 132. As tabs 180 are inserted through open end 172 of pressure jacket 170, annular surface 174 compresses first ends 62 of tabs 180 until they clear shoulder 175. The syringe 112 is then held firmly in place. When it becomes necessary to remove syringe 112 from pressure jacket 170, a reciprocating collar 68 extends forwardly within pressure jacket 170 (described in more detail below) to compress first ends 62 so that they no longer engage shoulder 174. The syringe 112 may then be removed from the pressure jacket 170.
However, the tabs 30, 180 need not have the V-shaped appearance shown in fig. 1 and 4-8. As shown in fig. 9, it is contemplated that the second embodiment of the tab 30 has a b-shaped appearance. When the tabs 30 have a b-shaped appearance, they are integrally formed with the end of the syringe 412. When the tabs 30 have a b-shaped appearance, they have bulbous first ends 70 extending outwardly from second ends 72, which are spaced from adjacent tabs 30 by gaps 71 (best shown in fig. 14 and 15). Like first end 62, first end 70 engages shoulder 29 when the syringe is inserted into injector housing 18. Like first end 62, reciprocating collar 68 acting on first end 70 disengages them from shoulder 29 when syringe 412 is to be removed from injector 20.
For each embodiment of the tabs 30 contemplated by the present invention, it is also contemplated that the number of tabs used may vary while remaining within the scope of the present invention. For example, for the syringe 212, as shown in fig. 10 and 11, it is contemplated that only one tab may be provided at the end of the syringe. Only one tab 30 having a first end 70 and a second end 72 is shown in fig. 10 and 11. However, it should be understood that it may be conveniently substituted for the tab 30 having the first end 62 and the second end 64.
Although a single tab 30 may be used, it is preferred to use at least two tabs, since the tabs should be bent for optimum functioning. A syringe 312 having at least two tabs is shown in fig. 12 and 13. When two tabs are included on the syringe 312, it is contemplated that they may be disposed on opposite sides of the tubular body 32 to increase the stability of the secure engagement of the syringe 312 with the injector 20. The tabs are of suitable shape and have any of a variety of circumferential dimensions.
In another embodiment of the pressure jacket injector system shown in fig. 32, a syringe cap 1000 may be provided at the end of the pressure jacket 1002 to retain a syringe 1032 therein. Alternatively, cover 1000 may be attached to or molded as part of syringe 1032 and need not be a separate component. As shown in fig. 32, the pressure jacket 1002 is a modified version of the pressure jacket 170 shown in fig. 4 and 5. In accordance with the spirit of the present invention, cover 1000 includes tabs 1004 around its periphery. The tabs 1004 engage a protrusion 1006 around the end of the pressure jacket 1002. To disengage the tab 1004 from the protrusion 1006, a reciprocating collar 1008 is slid along the outside of the pressure jacket 1002. The collar 1008 includes a tapered surface 1010 to facilitate removal of the tab 1004 from the protrusion 1006. The actuator for the ring 1008 is not shown. However, one skilled in the art will readily appreciate that the loop 1008 can be manipulated manually, mechanically, or electrically (or in any other manner suitable for disengaging the tabs 1004 from the engaging projections 1006).
In yet another alternative embodiment of the device described in connection with fig. 32, the tabs may extend from the cap (which may be separate from, attached to, or integrally molded with the syringe) and engage the annular member 174 at the end of the pressure jacket 170 using the same method as the tabs 180 engage the annular member 174 in the embodiment shown in fig. 4 and 5. As with the embodiment shown and described in connection with fig. 4 and 5, the reciprocating collar is then positioned in the pressure jacket 170 to disengage the tabs from the annular member.
Elements for the release mechanism are shown in fig. 38 and 39. A reciprocating collar 1402 is shown here inside the pressure jacket 170. As shown, the reciprocating collar 1402 is configured at the ends of at least two supports 1404, which are also located inside the pressure jacket 170. To receive the bearings 1404, the inner wall 1406 of the pressure jacket 170 includes at least two tracks 1408 in which the bearings 1404 slide. When the syringe 1032 is to be removed from the pressure jacket 170, the reciprocating collar 1402 is moved forward in the pressure jacket 170 to disengage the tabs on the syringe 1032 from the annular member 174.
This arrangement may also be used in conjunction with the pressure jacket system shown and described in fig. 4 and 5. When syringe 132 is to be removed from pressure jacket 170, reciprocating collar 1402 moves forward in pressure jacket 170, compressing tabs 180 so that they no longer engage annular member 174. Once the tabs 180 clear the annular member 174, the syringe 132 may be removed from the pressure jacket 170.
Where the syringe 112 is to be inserted into the pressure jacket 170 shown in fig. 4 and 5, the b-shaped tab 190 may be added to the front end of the syringe 112 in the same manner as the tab 180 is applied. As shown in fig. 16, the tab 190 basically includes a loop 74 extending in a rearward direction from the second end 72 of the tab 190. As shown in fig. 17, loop 74 with tab 190 forms a V-shaped cross-sectional configuration. Like tabs 180, when tabs 190 are inserted into pressure jacket 170 (as shown in fig. 4 and 5), they will be compressed until they clear annular surface 174 and then expand to engage shoulder 175. The tabs 190 hold the syringe 112 securely in the pressure jacket 170 until disengaged by the reciprocating collar 68.
Fig. 18-20 illustrate the mounting and dismounting of the syringe 412. In fig. 18, a syringe 412 is shown prior to insertion into the injector front wall 16. The illustrated reciprocating collar 68 in the resting state will rest behind the first end 70 of the tab 30 after the tab 30 passes over the annular surface 128 and rests on the distal shoulder 129. In this embodiment, the illustrated annular surface 128 has a tapered cross-section, rather than the cylindrical cross-section shown in fig. 7 and 9. The tapered cross-section facilitates insertion of the syringe 412 into the hub 26 as the taper helps to compress the first end 70 of the tab 30 during insertion of the syringe 412 into the injector 20. Additionally, when the annular surface 128 is tapered, it may act as a guide surface for the syringe 412 (or any other embodiment disclosed) even if the syringe 412 is inserted into the front wall 16 with greater angular contact. In other words, the syringe 412 may be easily inserted into the front wall 16 even when the syringe 412 is not oriented exactly to the central axis of the hub 26.
As shown in fig. 19, once the syringe 412 is fully inserted into the front wall 16, the tabs 30 are stretched to engage the shoulders 129. The syringe 412 is then held firmly in place. As shown in fig. 19, the reciprocating collar 68 remains in its rest position until after the injection operation is completed.
After the injection operation is completed, the reciprocating collar 68 is moved forward, compressing the first end 70 of the tab 30 to disengage the tab 30 from the shoulder 129. Figure 20 shows the reciprocating collar 68 in this forward position. Compression of the tab 30 is also illustrated. The syringe 412 may then be removed from the injector 20.
The present invention also contemplates that it is preferable to attach the syringe to adapter 500 before the syringe is attached to injector 20. As will be appreciated by those skilled in the art, the adapter may be disposable or reusable. As will be appreciated by those skilled in the art, the syringe may have a different configuration than that disclosed herein. One adapter for a syringe is described in U.S. patent No.5,535,746 to Hoover et al, 7/16/1996, the disclosure of which is incorporated herein by reference. Other patents for exemplary adapters include U.S. Pat. No.5,520,653 and WO 97/36635, both assigned to the assignee of the present application and incorporated herein by reference.
In the embodiment shown in fig. 21, syringe 412 has a tab 30 with a b-shaped appearance that snap fits into the front end 502 of adapter 500. Of course, tabs having a V-shaped cross-section may be used instead. Adapter 500 includes an annular surface 528 having a distal shoulder 529 in its forward end 502 that first end 70 of tab 30 engages to hold syringe 412 securely in place. Syringe 412 may be configured with flange 46 engaging front end 502 of adapter 500 to prevent contrast media from entering injector housing 18 through adapter 500 in the event of a leak. The rear end 504 of the adapter 500 also preferably includes a flange 546 that mates with the annular ring 44 on the mounting assembly 14 of the injector 20. Flange 546 serves the same function as flange 46 on syringe 12, i.e., preventing contrast media (or any fluid contained in the syringe) from entering injector 20.
If the adapter 500 is attached to the syringe 32, the plunger 42 may need to be adjusted to accommodate the increased length of the overall structure. If so, a piston stretcher or adapter (not shown) is attached to the end of piston 42, as will be appreciated by those skilled in the art. Alternatively, the plunger 42 may be constructed of a length sufficient to accommodate syringes 32 of varying lengths.
In this particular embodiment, the adapter 500 includes a conventional connector 506, such as the connector described in U.S. patent No.5,535,746 or U.S. patent No.5,383,858. So configured, the adapter 500 allows the syringe 412 to be connected to an injector that is designed to receive only a syringe having a conventional connector 506.
In another embodiment of the adapter, as shown in fig. 22, a conventional syringe must be fitted into the injector that receives the syringe of the present invention. Here, the adapter 600 includes a tab 630 at its rear end 604. Tabs 630 function and function similarly to tabs 30 that secure the adapter to housing 18 by engaging shoulders 29 on mounting assembly 14. Tab 630 is disengaged from shoulder 29 by reciprocating collar 68. Adapter 600 also includes a flange 646 that is the same as in the other embodiments already described. Although the adapter 600 is shown with a syringe having a ridged end inserted therein, it should be understood that the adapter 600 may be conveniently designed so that its front end 602 may receive a conventional connector, such as the one described in U.S. patent No.5,535,746 or U.S. patent No.5,383,858.
Figures 23 and 24 show perspective views of a combination of two syringes 412 and an adapter 600. In this embodiment, the flange 46 is omitted. However, as shown in FIG. 22, a flange 46 may be included. Of course, the adapter includes only one tab, two tabs, or more than two tabs 630, as with syringe 212 (shown in fig. 10 and 11) and syringe 312 (shown in fig. 12 and 13). Fig. 23 and 24 show an adapter 600 having a plurality of tabs.
Two embodiments of a second releasable mechanism 40 for engaging and releasing the syringe plunger and injector piston will now be described in connection with fig. 25-29. Fig. 25 shows an electromagnetic release mechanism. Fig. 26-29 illustrate an electromechanical release mechanism.
As shown in fig. 25, plunger 738 is releasably coupled to piston 742 by an electromagnetic means. The front end 702 of the plunger 742 is provided with an electromagnetic coil 704 which can be actuated by application of an electrical current through an electrical conductor 706 of the plunger 742. At its rear end 707, the plunger 738 includes a magnetically attractive ring 708 made of iron, for example, to attract the solenoid 704 when the solenoid 704 is actuated. The cross-sections of the front end 702 of piston 742 and the recess 710 in the rear end 707 of plunger 738 are cylindrical. This allows the engagement of the piston 742 with the plunger 738 independent of the orientation of the plunger 738 in the syringe.
As shown in fig. 25, the operation of the second releasable mechanism 40 is as follows. When the syringe is inserted into the interface on the injector housing 18, the piston 742 extends into the syringe until its forward end 702 mates with the recess 710 of the plunger 738. The solenoid 704 is then actuated to retract the plunger 738. During the rearward movement of piston 742, the attraction between magnetically attractive ring 708 and solenoid 704 holds plunger 738 to the end of piston 742. Alternatively, solenoid 704 may be actuated to mate with plunger 738 before piston 742 is extended into the syringe. Once plunger 738 and piston 742 are electromagnetically attracted to each other, piston 742 can be moved within the syringe as desired. To disengage piston 742 from plunger 738 or to retract piston 742 without retracting plunger 738, the power to solenoid 704 need only be disconnected. Of course, piston 742 may advance plunger 738, for example, during an injection, without actuating solenoid 704.
A second embodiment contemplated for second releasable mechanism 40 includes an electromechanical connection between the piston and the plunger. This embodiment is shown in fig. 26-29.
In fig. 26-29, the piston 842 has a forward end 802 that engages a recessed area 804 formed in the rearward end 806 of the plunger 838. The front end 802 of the piston 842 includes a number of protrusions 808 that retractably extend therefrom. As shown in fig. 27, the protrusion 808 engages a notch or slot 810 formed in the plunger 838. The piston 842 and the front end 802 enclose the member 812. The mechanism 814, also housed in the piston 842, may actuate the component 812. Mechanism 814 receives power through wires 816.
As shown in fig. 28 and 29, the protrusion 808 is generally rectangular. They are connected to each other by a resilient member 818. As shown in fig. 29, the resilient member 818 biases the protrusions 808 so that they do not protrude from the front end 802 of the piston 842.
The operation of second releasable mechanism 40 will now be described in connection with fig. 26-29. When the syringe is inserted into the front wall 16 of the injector 20, the piston 842 extends forward to encounter the plunger 838. As shown in FIG. 29, when the piston 842 is extended forward, the mechanism 814 is not actuated to place the member 812 in the retracted state. In other words, the member 812 is contracted so that it is not located between the protrusions 808. As a result, as shown in fig. 29, the resilient member 818 biases the protrusions 808 so that they do not extend beyond the front end 802 of the piston 842.
Once the front end 802 of the piston 842 is mated with the recessed area 804 in the plunger 838, the mechanism 814 is actuated to extend the member 812 forward, between the protrusions 808, thereby forcing the protrusions 808 to extend out of the front end 802 of the piston 842. Once the protrusion 808 is extended, it will extend into the slot 810 in the plunger 838. Once so positioned, the piston 842 is connected to the plunger 838 such that rearward movement of the piston 842 is directly translated into corresponding rearward movement of the plunger 838.
When it becomes necessary for the syringe to be detached from the injector or for the piston 842 to be retracted without retracting the plunger 838, the mechanism 814 is actuated to withdraw the member 812 from between the protrusions 808. Once withdrawn, the resilient member 818 biases the protrusions 808 so that they no longer engage the slots 810. The piston 842 is then withdrawn from the plunger 838.
Two additional second releasable mechanisms 40 will now be described in connection with fig. 35-37.
In the embodiment shown in fig. 35, plunger 1238 is releasably coupled to piston 1242 by extension of elastomeric member 1202 disposed at a forward end thereof. The elastomeric member 1202 is a cylindrical element having an outer wall 1204 and an inner wall 1206. A rod 1208 extends through the piston 1242 and is connected to the actuator 1210 at the forward end of the rod 1208 closest to the plunger 1238. The actuator 1210 has a frustoconical shape on the side facing the elastomeric member 1202. The frustoconical shape defines an inclined surface 1212 on the actuator 1210. The diameter of the elastomeric member 1202 is slightly smaller than the diameter of the bore 1214 in the plunger 1238. Likewise, the diameter of the actuator 1210 is smaller than the diameter of the bore 1214.
The operation of second releasable mechanism 40 shown in fig. 35 will now be described. Because the diameter of the bore 1214 in the plunger 1238 is greater than the diameter of the actuator 1210 and the elastomeric member 1202, the elastomeric member 1202 and the actuator 1210 can easily fit into the bore 1214 when the piston 1242 is pushed forward. The plunger 1238 can then be advanced by the piston 1242 without connective engagement therebetween. However, once positioned in this manner, as indicated by arrow 1216 in fig. 35, the actuator 1210 is pulled toward the elastomeric member 1202 by the rod 1208 for connective engagement with the plunger 1238 (e.g., retracting the plunger). Pressure from actuator 1210 compresses elastomeric member 1202 to expand or extend outer sides 1204 from their unstressed state. The general shape of the expansion wall 1218 of the elastomeric member 1202 is shown in phantom in fig. 35. The expansion wall 1218 engages the wall 1220 of the aperture 1214 to releasably engage the piston 1242 with the plunger 1238. The plunger 1238 may now be retracted, for example, to draw fluid into the syringe.
The embodiment of second releasable mechanism 40 shown in fig. 36-37 will now be described. As shown in fig. 36-37, plunger 1338 engages piston 1342 through segment member 1302. The segment member 1302 is made up of a plurality of discrete elements 1304 shown in end view in fig. 37. The separating element 1304 can be made of any suitable material, such as an elastomeric material, so long as the material is preferably (1) substantially resistant to repeated deformation and (2) substantially returns to its original state when it is no longer subjected to the deforming stress. The segment member 1302 is disposed at the front end of the piston 1342. A rod 1306 extends through the middle of the piston 1342 and at least partially into the central bore 1308 of the segment member 1302.
To releasably connect the plunger 1338 with the piston 1342, the piston 1342 is moved forward until the segment member 1302 is disposed within the bore 1310 formed in the plunger 1338. Rod 1306 is then moved forward in the direction indicated by arrow 1312 until rod 1306 is at least partially disposed within segment member 1302. Because the rod 1306 has a diameter greater than the diameter of the hole 1308, inserting the rod 1306 into the hole 1308 can push the segment members 1304 outward until they reach a deformed position 1314 shown in phantom in fig. 36 and 37. Upon deformation, the segment member 1304 engages the wall 1316 of the bore 1310 in the plunger 1338 to form a releasable engagement between the plunger 1338 and the piston 1342.
For each of the second releasable mechanisms described in fig. 25-29 and 35-37, the mechanism provides the advantage that the plunger need not orient the piston in any particular manner to facilitate connection between the piston and the plunger. Regardless of the orientation of the piston and plunger, the two may conveniently be a close fit with one another and may conveniently be disengaged from one another.
Additionally, if, for example, a pre-filled syringe is mounted on the injector, the fluid in the syringe can be aspirated for a subsequent injection without having to retract the plunger in the syringe. In this case, the piston may operate in a "push only" mode that does not require engagement between the piston and the plunger. If operated in this manner, the engagement mechanism need not be actuated at all. Alternatively, if the injector is designed to control only pre-filled syringes, it is desirable to provide a mechanism that does not facilitate release.
The plunger of the present invention also includes a pressure sensor similar to that described in U.S. patent No.5,808,203 to small Nolan et al, 9/15 of 1998 and assigned to the assignee of the present application. To the extent consistent with this disclosure, the disclosure of U.S. Pat. No.5,808,203 is incorporated herein by reference.
Fig. 30 and 31 illustrate sensors that may be included in the plunger of the present invention. The plunger 938 preferably includes a base 902 having a passage 904 therethrough. A detection member 906 is arranged in the channel 904 to be in contact with a portion P of the contact surface 908 during operation. The sensing member 908 is preferably biased forward, such as by a spring 910. As shown in fig. 31, as the fluid pressure in the syringe (not shown) increases, a portion P of the contact surface 908 deforms. This deformation of portion P causes detection member 906 to move rearward through channel 904 and 912 and 914 in piston 942. The movement of the sensing member 906 is monitored using a sensor 916 preferably disposed in the plunger 942. Since the extent of movement of the detection member 906 is a function of the pressure of the fluid medium in the syringe, the pressure of the fluid medium can be determined therefrom. The sensor 916 is preferably connected to a data collection and/or control device by a lead 918.
Although fig. 30 and 31 depict one possible embodiment of a sensor that may be incorporated into the plunger of the present invention, it should be noted that any suitable sensor may be included. In addition, the sensor need not only detect the pressure of the fluid. As will be appreciated by those skilled in the art, the sensors may measure a number of different parameters, including the amount, pressure and density of fluid in the syringe.
Also, the plunger includes a coding element that is read or detected by the injector or injector piston to identify the syringe and/or the object contained therein. In this embodiment, the coding element (e.g., an integrated circuit) is included on the plunger rather than on the syringe. The coding element is then read electronically as the plunger contacts the piston. The plunger includes information such as the contents and volume of the syringe, as well as other information required for procedural or accounting purposes. An example of such a system is that described in PCT publication No. wo 99/65548, which is incorporated herein by reference.
The invention as shown and described herein is often referred to by the term "cooperation of the injector interface and the injector". The terms "syringe interface" and "syringe interfaces" as used herein may be combined or integrated with a new medical injector or be configured to mount or associate with a syringe adapter on an existing or conventional medical injector, such as the injector shown and described in U.S. Pat. No.5,383,858, the contents of which are incorporated herein by reference, to mount the syringe of the present invention thereon.
Fig. 40A-40C illustrate yet another embodiment of a front-loading injector interface and injector system 1500 of the present invention. The system 1500 includes an injector 1512 and an injector interface 1514. The syringe 1512 includes a body or barrel portion 1516 having a rearward end 1520 and a forward end 1517 that defines a fluid discharge end 1518. At least one tab or mounting member 1522 is preferably associated with the sleeve portion 1516 at or near the rear end 1520 of the syringe 1512. Additionally, as described in more detail in U.S. patent No.5,383,858, the flange 1524 is preferably positioned forward of the mounting member 1522 to facilitate engagement of the syringe 1512 with the syringe interface 1514 and/or to prevent fluid discharged from the discharge end 1518 of the syringe from entering the syringe interface 1514 and the injector (not shown).
The mounting member 1522 is preferably disposed about the perimeter of the sleeve portion 1516 and includes an angled surface 1526 defining a shoulder 1528. The function of the mounting member 1522 will be described in detail below. Alternatively, the mounting member 1522 extends around only a portion of the circumference of the sleeve portion 1516, or forms a discontinuous segment.
(unless otherwise noted, the injector 1512 (and its components) described above apply to the remaining embodiments of the invention discussed and described below in connection with FIGS. 40A-47F.)
As best shown in fig. 40A and 40C, the syringe interface 1514 is in an "open" position ready to receive a syringe 1512. Syringe interface 1514 includes a base member 1530 and two cooperating syringe retaining members 1532. However, in alternative embodiments, three or more retaining members 1532 may be provided. Each retaining member 1532 is preferably associated with the base member 1530 by two angled rail members 1534. However, in alternative embodiments, one, three, or more members 1534 may be used such that each retaining member 1532 is associated with the base member 1530.
In addition, each retaining member 1532 preferably defines a contact surface 1533 and a slot 1536 to capture and retain the mounting member 1522 on the syringe 1512. In addition, the retaining members 1532 are preferably associated with each other by two rail members 1538. Also, in alternative embodiments, one, three, or more rail members 1538 may be used to associate the retention members 1532 with each other.
To mount the syringe 1512 on the syringe interface 1514, the syringe 1512 is moved axially (in the direction of arrow a in fig. 40A) into the space formed between the retaining members 1532. When the flange 1524 on the syringe 1512 engages the contact surfaces 1533 on the retaining members 1532, the retaining members 1532 are urged along the rail members 1534 toward the base member 1530. Because the rail members 1534 are angled toward the center of the base member 1530, operation of the rail members 1534 causes the retaining members 1532 to move along the rail members 1538 with respect to each other and "collapse" around the rear end 1520 of the syringe 1512. As the retaining members 1532 collapse on the syringe 1512, the retaining members 1532 cooperate to capture the mounting member 1522 in the channel 1536 to securely engage the syringe 1512 with the syringe interface 1514.
As is known in the art, any suitable type of locking mechanism (not shown) may be used to secure the retaining members 1532 together to retain the syringe interface 1512 within the syringe interface 1514. To remove the syringe 1512 from the syringe interface 1514, the lock must first be released and the retaining member 1532 removed (e.g., by hand or by means of a lever or any other suitable control device recognized in the art) to disengage the mounting member 1522 from the slot 1536.
Yet another embodiment of a syringe interface and syringe system 1600 is shown in fig. 41A-41D. The system 1600 includes a syringe 1512 and a syringe interface 1614. As best shown in fig. 41B and 41C, the syringe interface 1614 is in an "open" position ready to receive a syringe 1512. The syringe interface 1614 includes a base member 1630 and two cooperating syringe retaining members 1632. The retaining members 1632 are preferably connected together by a pivot pin 1631 or other suitable mechanism (see FIG. 41D) and associated with the base member 1630. In addition, retaining member 1632 is associated with base member 1630 by a pin 1629 (see fig. 41D), which pin 1629 is associated with retaining member 1632 and captured within a slot 1635 defined in base member 1630.
In addition, each retaining member 1632 preferably defines a slot 1636 to capture and retain the mounting member 1522 on the syringe 1512. As best shown in fig. 41B and 41C, a spring pin 1637 (or other suitable locking mechanism) is connected to one retaining member 1632, while the other retaining member 1632 defines a slot therein having a pin recess 1640. Additionally, two cannula guide rails 1639 are preferably defined in base member 1630.
To mount the syringe 1512 on the syringe interface 1614, the syringe 1512 is moved downwardly (in the direction of arrow B in fig. 41B) into the space formed between the retaining members 1632. The cannula 1516 of the syringe 1512 is guided into position between the retaining members 1632 by cannula guides 1639 in the base member 1630. When the syringe sleeve 1516 engages the pivot end 1651 of the retaining member 1632 (see fig. 41C), the retaining member 1632 is caused to collapse around the rear end 1520 of the syringe 1512. The pins 1629, which are positioned within slots 1635 defined by the base member 1630, guide and control the arcuate movement of the retaining member 1632 into engagement about the syringe 1512. As the retaining members 1632 collapse onto the syringe 1512, the retaining members 1632 cooperate to capture the mounting member 1522 within the channel 1636 to securely engage the syringe 1512 with the syringe interface 1614.
In addition, when the retaining member 1632 is collapsed around the syringe 1512, the spring pin 1637 moves along the slot and locks into the pin recess 1640, securing the syringe 1512 in the syringe interface 1614. To remove the syringe 1512 from the syringe interface 1614, the spring pins 1637 must be removed from the pin recesses 1640 to release the retaining members 1632 and disengage the retaining members 1632 from the syringe 1512 (e.g., by hand or any suitable lever arrangement). At this point, the syringe 1512 may be removed by moving the syringe 1512 upward (in the direction opposite to arrow B) or axially (in the direction of arrow C in 41B).
Fig. 42A-42D illustrate another embodiment 1700 of the syringe interface and syringe system 1600 illustrated in fig. 41A-41D. The system 1700 includes a syringe 1512 and a syringe interface 1714. As best shown in fig. 42C and 42D, the syringe interface 1714 differs from the syringe interface 1614 of fig. 41A-41D in that the retaining member 1732 includes a pivot end 1751 located at an end of the retaining member 1732 remote from the pivot pin 1731. In addition, as shown in fig. 42D, the retaining members 1732 are preferably resiliently biased in a "closed" or "engaged" position to retain the syringe 1512 in the syringe interface 1714.
To mount the syringe 1512 on the syringe interface 1714, the syringe 1512 is moved downward (in the direction of arrow D in fig. 42B) into engagement with the retaining member 1732. When the syringe cannula 1516 engages the pivot ends 1751 of the retaining members 1732, the retaining members 1732 are urged apart against the spring force to pass the syringe cannula 1516 between the pivot ends 1751 and into the space defined between the retaining members 1732. The syringe mounting member 1522 is guided by the slots 1736 defined in the retaining member 1732 to properly position the syringe 1512 in the syringe interface 1714. Once the syringe 1512 passes the pivot end 1751, the spring force causes the retaining members 1732 to collapse around the rear end 1520 of the syringe 1512. A pin 1729 positioned in a slot 1735 defined by the base member 1730 guides and controls the arcuate movement of the retaining member 1732 into engagement about the syringe 1512. As the retaining members 1732 are condensed on the syringe 1512, the retaining members 1732 cooperate to capture the mounting members 1522 in the channels 1736 to securely engage the syringe 1512 in the syringe interface 1714.
To remove the syringe 1512 from the syringe interface 1714, the syringe 1512 is moved upward (in the opposite direction of arrow D) against the pivot ends 1751 of the retaining members 1732. When the upward force on the syringe 1512 overcomes the spring force that holds the retaining members 1732 together, the retaining members 1732 will separate and slide the syringe 1512 off of the syringe interface 1714.
Fig. 43A-43I illustrate yet another alternative embodiment 1800 of the syringe interface and syringe system 1600, 1700 shown in fig. 41A-42D. The system 1800 includes a syringe 1512 and a syringe interface 1814. As best shown in fig. 43B and 43H, the syringe interface 1814 differs from the syringe interfaces 1614, 1714 of fig. 41A-42D in that the retaining member 1832 includes an extension member 1855 and a chamfer 1857. The extension member 1855 is preferably manipulated to move the keeper member 1832 to the open position (i.e., against the spring force holding the keeper member 1832 in the closed position). The inclined surface 1526 of the mounting member 1522 of the syringe 1512 operably engages the chamfer 1857 to cause the retaining members 1832 to open and the syringe 1512 to be axially mounted (in the direction of arrow E in fig. 43C) on the syringe interface 1814. The remaining structure of the syringe interface 1814 is substantially similar or identical to the structure of the syringe interface 1714 described above.
As best shown in fig. 43E, the syringe 1512 can be mounted and removed from the syringe interface 1814 using substantially the same methods as described above in connection with fig. 42A-42D. In addition, however, as best shown in fig. 43A, 43C, 43F and 43G, the syringe 1512 may be axially mounted and removed from the syringe interface 1814. Thus, the syringe interface 1814 accommodates two methods of mounting/dismounting the syringe 1512.
To axially install the syringe 1512, the syringe 1512 is inserted into the syringe interface 1814 until the mounting members 1522 engage the retaining members 1832. The angled surface 1526 of the mounting member 1522 engages the chamfer 1857 on the retaining member 1832 thereby forcing the retaining member 1832 apart against the spring force. After the mounting member 1522 passes over the chamfered region, the retaining members 1832 collapse and capture the mounting member 1522 around the slots 1836 to secure the syringe 1512 to the syringe interface 1814.
To axially disassemble the syringe 1512, the extension members 1855 of the retaining members 1832 are manipulated (i.e., pressed together) to overcome the spring force and urge the retaining members 1832 apart. When the retaining members 1832 are moved apart to the extent that the mounting members 1522 of the syringe 1512 are no longer engaged in the slots 1836, the syringe 1512 may be axially removed (in a direction opposite to arrow E) from the syringe interface 1814.
Fig. 44A and 44B illustrate a first, slightly modified embodiment of the syringe interface 1814 shown in fig. 43A-43I, incorporated or mounted on an injector head. The functionality of the syringe interface 1914 is substantially similar or identical to that described above in connection with the syringe interface 1814.
Fig. 45A and 45B illustrate a second, slightly modified embodiment of the syringe interface 1814 shown in fig. 43A-43I, incorporated or mounted on an injector head. The functionality of the syringe interface 2014 is substantially similar or identical to that described above in connection with the syringe interface 1814.
Fig. 46A-46D illustrate a first preferred embodiment of a front-loading injector interface and injector system 2100 of the present invention. The system 2100 includes an injector 1512 and an injector interface 2114. As best shown in fig. 46A, the syringe interface 2114 includes a flexible retaining ring 2150 disposed between the rear plate 2152 and the front plate 2154. The retaining ring 2150 defines a rear shoulder 2160, the shoulder 2160 being adapted to engage the mounting member 1522 of the syringe 1512 when the syringe 1512 is mounted in the syringe interface 2114.
The ring 2150 includes at least one, but preferably two release members 2156 and at least one, but preferably two protrusion members 2158. In addition, as will be described in greater detail below, the ring 2150 is preferably oval in shape so as to be engageable and disengageable with the mounting member 1522 of the syringe 1512. As best shown in fig. 46B-46D, a release member 2156 projects from the rear and front plates 2152, 2154 for manipulation, such as by an operator, to release the syringe 1512 from the syringe interface 2114. In addition, the tab members 2158 are captured and slide within slots (not shown) defined in the back side (not shown) of the front plate 2154, and the syringe 1512 can be removed from the syringe interface 2114 when only one release member 2156 can be manipulated in place of two release members 2156. (the slots are described below in connection with the alternative embodiment of FIGS. 47A-47F and shown in FIG. 47E.)
To mount the syringe 1512 on the syringe interface 2114, the syringe 1512 is moved axially (in the direction of arrow F in fig. 46C) into engagement with the syringe interface 2114. When the mounting member 1522 engages the retaining member 2150, the mounting member 1522 causes the flexible, oval-shaped ring 2150 to assume a more circular configuration, thereby moving the mounting member 1522 over the ring 2150. After the mounting member passes the ring 2150, the ring 2150 returns to its original shape, thereby capturing the mounting member 1522 behind its rear shoulder 2160 and securing the syringe 1512 to the syringe interface 2114.
A tab member 2158 and slot (not shown) are provided to control/limit movement of the retaining ring 2150 during syringe installation and removal. More specifically, the movement of the ring 2150 is guided and controlled by the protrusion members 2158 that are slidable within the slots (i.e., from generally oval to generally circular and from generally circular to generally oval) during syringe installation and removal. Thus, regardless of the orientation of the syringe 1512 and the retaining ring 2150 during initial engagement, the protrusion members 2158 and grooves can guide and limit the force of the syringe acting on the ring 2150 and the resulting movement of the ring 2150.
To remove the syringe 1512 from the syringe interface 2114, one or both release members 2156 are pressed inward (i.e., toward the center of the syringe interface 2114), thereby forcing the ring 2150 out of engagement with the mounting member 1522 of the syringe 1512. When the release member 2156 is actuated, the syringe 1512 is grasped and moved axially (in the opposite direction of arrow F in fig. 46C) to remove the syringe 1512 from the syringe interface 2114.
When the release member 2156 is actuated, the protrusion member 2158 slides in a slot (not shown) that guides the movement of the ring 2150 from a generally oval configuration to a generally circular configuration such that the mounting member 1522 no longer engages the rear shoulder 2160 of the ring 2150.
It will be appreciated that the present embodiment may use a simple, single-step axial motion to mount the syringe 1512 to the syringe interface 2114. To remove the syringe 1512, one or both release members 2156 are depressed and the syringe 1512 is simply axially removed from the syringe interface 2114.
Fig. 47A-47F illustrate another embodiment 2200 of the system 2100 illustrated in fig. 46A-46D. The structure and operation of the system 2200 is substantially similar and identical to the system 2100 described above in fig. 46A-46D, except that the release member 2256 is greatly enlarged to make manipulation easier and simpler.
As discussed above in connection with fig. 46A-46D, fig. 47E illustrates a slot 2270 formed in the front plate 2254 and a protrusion member 2258 captured in the slot 2270.
Fig. 48A-48C illustrate yet another embodiment of a front-loading injector interface and injector system 2300 of the present invention. The system 2300 includes a syringe 2312 and a syringe interface 2314. Unlike the syringe 1512 shown in fig. 40A-47F and discussed and described in connection with other syringe interface and syringe system embodiments of the present invention, the syringe 2312 preferably includes (in addition to other components of the syringe 1512) two grooves 2327 formed in the rear thereof. Alternatively, one, three, or more grooves 2327 may be formed in syringe 2312.
The syringe interface 2314 preferably includes a base member 2360 and a collet member 2362 rotatably mounted in the base member 2360. Base member 2360 preferably includes two dowels 2364 inserted therein as will be described in detail below. The collet member 2362 includes a plurality of segment members or tangs 2368 formed therein, a helical track 2370 defined in the rearward end thereof, and at least two posts 2372 that operably engage the grooves 2327 in the syringe 2312. Preferably, a small detent 2374 is formed in the helical track 2370 at a suitable location (e.g., at or near the terminal end thereof) for reasons described below. The collet member 2362 is held in the base member 2360 by dowels 2364 that are captured and located within helical tracks 2370 in the collet member 2362.
To mount the syringe 2312 on the syringe interface 2314, the grooves 2327 on the syringe 2312 are aligned with the posts 2372 on the collet member 2362, and the syringe 2312 is inserted axially (in the direction of arrow G in fig. 48B) into the collet member 2362 until the grooves 2327 engage the posts 2372. The syringe 2312 is then rotated (preferably clockwise in the direction of arrow H in fig. 48B and approximately 90 °) relative to the initial syringe position to complete the installation. As the syringe 2312 is rotated, the engagement between the posts 2372 on the collet 2362 and the grooves 2327 on the syringe 2312 will cause the collet member 2362 to rotate in unison with the syringe 2312 in the base member 2360.
As the collet member 2362 rotates with the syringe 2312, the dowel pins 2364 located in the helical track 2370 pull the collet member 2362 into the base member 2360. As the collet member 2362 is pulled into the base member 2360, each tang 2368 is urged into engagement with the mounting member 2322 of the syringe 2312 by the inclined surfaces 2365 of the base member 2360, thereby securing the syringe 2312 to the syringe interface 2314. As can be appreciated, engagement of the "post and groove" prevents rotation of the syringe relative to the collet member 2362, while engagement of the "tang and mounting member" prevents translation of the axial syringe.
When the syringe 2312 (and collet member 2362) are fully rotated into the base member 2360, the dowel 2364 snaps into place in the small detent 2374 to provide tactile (and possibly audible) feedback to the operator that the syringe 2312 is fully and securely mounted in the syringe interface 2314.
To remove the syringe 2312 from the syringe interface 2314, the syringe 2312 (and collet member 2362) are rotated (preferably in a counterclockwise direction opposite to the direction of arrow H) within the base member 2360. To initiate rotation, sufficient force must be applied to the syringe 2312 (and collet member 2362) to disengage the dowel 2364 from the pawl 2374 and seat along the helical track 2370. The syringe 2312 is then rotated until the dowel 2364 snaps into place in the detent 2374 at the opposite end of the helical track 2370. (tactile (and possibly audible) feedback that the pin 2364 is snapped into place will prompt the operator that the syringe 2312 can be removed from the collet member 2362.) as the collet member 2362 rotates out of the "closed" position in the base member 2360, the tangs 2368 release the mounting member 2322 of the syringe 2312 and the syringe 2312 is removed axially (in the opposite direction of arrow G) from the syringe interface 2314.
Fig. 49A-49F illustrate yet another embodiment of an injector piston and syringe plunger interface system 2400 of the present invention. System 2400 can be incorporated into the injector interface and injector system described above. The system 2400 includes an injector piston 2402 having a piston head 2410 and a syringe plunger 2404 that preferably includes a plunger base 2406 and a plunger cover 2408. As best shown in fig. 49F, plunger base 2406 and plunger cover 2408 (which may be made of rubber) are preferably interconnected by a mechanical connection.
As described below, the piston head 2410 and plunger base 2406 are preferably engaged with each other via a bayonet-type interlock mechanism. As is known in the art, the piston 2402 is preferably disposed in an injector (not shown), and the plunger 2404 is preferably disposed in a syringe, such as the syringes 1512, 2312 described above.
Piston head 2410 preferably includes a pair of extension flanges 2412, as best shown in fig. 49E, and plunger base 2406 preferably includes a pair of retaining flanges 2414 separated by a slot 2416. To connect piston 2402 and plunger 2404, an extending flange 2412 on piston head 2410 is inserted into plunger 2404 along slot 2416. When the extension flange 2412 clears the retention flange 2414, (preferably indicated by flange 2427 on piston 2402 engaging contact surface 2430 on plunger 2404), the piston 2402 or plunger 2404 is rotated such that the retention flange 2414 is captured behind the extension flange 2412. To disengage piston 2402 from plunger 2404, the operator preferably reverses the steps.
As will be appreciated by those skilled in the art, piston 2402 and plunger 2404 may be engaged by translating and rotating plunger 2404 (disposed in a syringe) into engagement with piston 2402 (disposed in an injector), and vice versa. Alternatively, translational and rotational motion may be exchanged between plunger 2404 and piston 2402 to interconnect the two members.
Fig. 50A and 50B illustrate yet another embodiment of an injector piston and syringe plunger interface system 2500 of the present invention. The system 2500 preferably includes a piston 2502 and a plunger 2504. Plunger 2504 is preferably constructed as shown and described above in connection with fig. 49A-49F. The piston 2502 preferably includes a piston head 2510 with a collet-type mechanism 2530. Collet 2530 preferably comprises a plurality of flexible segment members or tangs 2534.
To connect the piston 2502 and plunger 2504, the collet mechanism 2530 is inserted into the plunger 2504. When the tangs 2534 pass through the undercut 2536 of the plunger (as best shown in fig. 50B), a rod or pin member (not shown) is preferably driven through the center of the collet mechanism 2530 to radially separate the tangs 2534 into locking engagement with the undercut 2536 of the plunger. To disengage the piston 2502 from the plunger 2504, a rod or pin member (not shown) is retracted from the center of the collet mechanism 2530, thereby disengaging the tangs 2534 from the undercut slots 2536 of the plunger.
Due to the symmetrical nature of the collet mechanism 2530, engagement and/or disengagement of the piston 2502 and plunger 2504 with each other does not require special alignment between the piston 2502 and plunger 2504. This feature simplifies the mounting and dismounting of the syringe from the syringe interface.
As will be appreciated by those skilled in the art, the piston 2502 and plunger 2504 may be engaged by translating the plunger 2504 (disposed in the syringe) into engagement with the piston 2502 (disposed in the injector), and vice versa.
Fig. 51A-51C illustrate another embodiment 2600 of the injector piston and syringe plunger interface system 2500 shown in fig. 50A and 50B. The structure and operation of the system 2600 is substantially similar and identical to the system 2500 shown in fig. 50A and 50B, except that a collet mechanism 2630 is configured to complement the shape of the plunger cap 2608 to support the plunger cap 2608 during an injection procedure and to provide for monitoring fluid pressure by the plunger 2604, such as described in U.S. patent No.5,808,203, the contents of which are incorporated herein by reference.
Fig. 52A-52C illustrate yet another embodiment of an injector piston and syringe plunger interface system 2700 of the present invention. System 2700 includes a plunger 2702 and a plunger cover 2708. In contrast to the above embodiments, no plunger base is present in the plunger 2704. Conversely, piston head 2710 is configured to complement the shape of plunger cover 2708 in order to support plunger cover 2708 during fluid injection.
As best shown in fig. 52A, piston 2702 preferably includes a base member 2760, a sleeve 2762, a segmented baffle member 2764, and a piston cover 2766. During forward movement of plunger 2702 (i.e., during fluid injection), plunger 2702 preferably contacts and moves plunger cover 2708 and does not connectively engage or lock therewith. As piston 2702 (i.e., base member 2760, baffle member 2764, and cover 2766) is retracted, sleeve 2762 is moved (in the direction of arrow I in fig. 52B) into contact with segmented baffle member 2764 and baffle 2765 is urged radially outward into engagement with undercut groove 2767 formed in plunger cover 2708 (as best shown in fig. 52C) to connect piston 2702 and plunger cover 2708 together. The co-retraction of plunger 2702 and plunger cover 2708 is useful, for example, during the aspiration of fluid into a syringe for subsequent injection into a patient.
Fig. 53A-53D illustrate yet another embodiment 2800 of the injector piston and syringe plunger interface systems 2600, 2700 shown in fig. 51A-51C and 52A-52C. System 2800 functions substantially similar or identical to systems 2600, 2700, but with different structural components as will be explained below.
53C and 53D, an actuator 2870 disposed in the piston 2802 acts on the collet mechanism 2830 to urge the tangs 2834 radially outwardly into engagement with undercut slots 2836 formed on the plunger cap 2808 to interconnect the piston 2802 and the plunger cap 2808. The collet mechanism preferably includes a resilient retaining member 2872 (e.g., an O-ring) to hold the tangs 2834 together and to resiliently bias the tangs in the "disengaged" position.
Fig. 54A and 54B illustrate a prior art syringe plunger 2980 that includes a plunger base 2984 and a mechanically coupled plunger cover 2982.
Fig. 54C and 54D illustrate one embodiment of a plunger 3080 of the present invention. The plunger 3080 includes a plunger cover 3082 having a larger syringe contact area (as compared to the plunger cover 2982 shown in fig. 54A and 54B) and at least three sealing members 3083. As shown and described in PCT publication No. wo 98/20920, plunger base 3084 includes at least two flexible piston retaining members 3085, the contents of which are incorporated herein by reference. As best shown in fig. 54D, the plunger cover 3082 is preferably mechanically connected to the plunger base 3084.
Fig. 54E and 54F illustrate yet another embodiment of a plunger 3180 of the present invention. The plunger cover 3182 is substantially similar or identical to the plunger cover 2982 shown in fig. 54A and 54B. Plunger base 3184 includes at least two flexible piston retaining members 3185.
Fig. 54G and 54H illustrate another embodiment of a plunger 3280 of the present invention. Plunger cover 3282 is substantially similar or identical to plunger cover 2982 shown in fig. 54A and 54B. Plunger base 3284 includes a longer base region and at least two flexible piston retaining members 3285.
As can be appreciated, the plungers 2980, 3080, 3180, 3280 shown and described above may be incorporated into the syringes 1512, 2312 described herein.
The preferred embodiment of the present invention is described in conjunction with FIGS. 55-109. In these drawings, FIGS. 55-78 are directed to a second preferred embodiment of a syringe engagement/release mechanism for releasably securing a syringe to an injector housing. Fig. 79 illustrates the efficacy of a flange assembly associated with a syringe of a related art medical injector assembly, which efficacy applies equally to the efficacy of a flange on a syringe of the present invention. Fig. 80-109 illustrate a first preferred embodiment of the injector piston and syringe plunger interface system/assembly of the present invention, the cooperation of which causes axial movement of the plunger in the syringe.
In other features (shown in fig. 55-57), the second preferred embodiment of the syringe interface of the present invention surrounds a release mechanism 4010 for connecting the syringe 4012 to the injector 4014.
In particular, the second preferred embodiment of the present invention provides a mechanism by which the syringe 4012 can be quickly attached to the injector 4014 without requiring (as is the case in the prior art) any particular orientation of the syringe 4012 and injector 4014 during installation. The release/connector mechanism 4010 of the invention also provides an audible "click" when the syringe 4012 is fully engaged with the connector/release mechanism 4010. In addition, the present invention provides an audible "click" when the syringe 4012 disengages the release/connector mechanism 4010. An audible "click" for connection and disconnection of the syringe 4012 to the release/connector mechanism 4010 is a particularly useful feature since it provides an audible confirmation to the operator that the syringe 4012 is properly engaged and disengaged from the release/connector mechanism 4010.
Fig. 55 generally illustrates a syringe interface/release mechanism 4010 (hereinafter referred to as release or connector mechanism 4010 for simplicity) of the present invention. The rear face 4016 of the release mechanism 4010 is attached to the front face 4018 of the injector 4014. The front face 4020 of the release mechanism 4010 is adapted to receive the rear end 4022 of the syringe 4012.
The release mechanism 4010 can be secured to the front surface 4018 of the injector 4014 in any suitable manner known to those of ordinary skill in the art. The release mechanism 4010 is attached, for example, by a screw (not shown) extending from the front 4018 of the injector 4014. Any suitable alternative connection may be used, as will be appreciated by those of ordinary skill in the art. The release mechanism 4010 is secured, for example, by tabs or other suitable connections that allow the release mechanism 4010 to be detached from the injector 4014 for cleaning the components contained therein. In addition, the release mechanism 4010 is adapted to be mounted on a conventional injector for use with the syringe of the present invention.
The second preferred embodiment of the syringe interface/release mechanism shown in fig. 55-78 includes a connector housing 4024. The connector housing 4024 houses at least two components that facilitate connection of the syringe 4012 to the injector 4014. The first of the two elements is a flexible ring 4026 disposed near the front end 4020 of the release mechanism 4010. The second of the two elements is a rotating ring 4028 that is disposed proximate the rear end 4016 of the release mechanism 4010. As will be described in detail below, the flexible ring 4026 and the rotating ring 4028 are adapted to cooperate to connect and release the syringe 4012 to the release mechanism 4010 (and thus the injector 4014).
Fig. 56 and 57 show exploded perspective views of the release mechanism 4010 and syringe 4012 to facilitate an understanding of this aspect of the invention. Injector 4012 includes a cylindrical body 4030 having a tapered conical portion 4032 at a front end 4034. The conical portion 4032 is integrally connected to the discharge end 4036. The discharge end 4036 is provided with a luer lock 4038 which is connectable to a tube (not shown) which is ultimately connected to a patient (also not shown).
As will be appreciated by those of ordinary skill in the art, the syringe 4012 may be made of any suitable material, such as a polymeric material. In particular, the syringe 4012 can be made of PET (polyethylene terephthalate). Alternatively, syringe 4012 may be composed of polymethylpentene (trade name "TPX" manufactured by Mitsui plastics).
At rear end 4022, syringe 4012 includes a flange 4042 that helps to substantially prevent contrast media that may be oozed from, for example, discharge end 4036 or luer lock 4038 from entering release/connector mechanism 4010 when syringe 4012 is coupled to release mechanism 4010. A related art syringe is illustrated in figure 79, which helps illustrate the advantages provided by flange 4042 on syringe 4012.
As shown in fig. 55-57, a ridge 4044 is integrally formed on the syringe 4012 behind a flange 4042 towards the rear end 4022 of the syringe 4012. Ridge 4044 comprises two parts: an angled portion 4046 and a shoulder 4048, which is substantially perpendicular to the outer surface of the cylindrical body 4030. At the rearward end 4022 of the syringe 4012, there is provided at least one, and preferably two or more, extending tabs or protrusions 4050. Tabs 4050 engage grooves 4052 in ring 4028. Alternatively, as will be appreciated by those of ordinary skill in the art, slots, recesses, divots, or the like can be provided in the back end 4022 of the syringe 4012, and tabs or protrusions can be provided on the inner surface of the rotating ring 4028.
Additionally, to mount a conventional syringe to the syringe interface 4010 of the present invention, a syringe adapter incorporating the structural components (e.g., the ridges 4044, tabs 4050, and/or flanges 4042) of the rear end 4022 of the syringe 4012 can be adapted to fit to a conventional syringe for mounting the conventional syringe to the injector of the present invention. Of course, in order to properly engage a conventional syringe, the adapter preferably includes a structural assembly that is complementary to the mounting elements of the conventional syringe.
Release/connector mechanism 4010 includes a front plate 4054 and a rear plate 4056. The front and back panels 4054, 4056 are preferably made of a coated fluoropolymer (e.g., Tufram manufactured by General Magna Plate, Inc. under the product nameTMThe fluoropolymer of (a). The fluoropolymer coating provides improved wear resistance and also provides lubricity of the outer surfaces of the front and rear portions 4054, 4056. The lubricating ability is particularly advantageous because when the contrast agent crystallizes on the outer surface of the front plate 4054 or the rear portion 4056, since the surface is coated with the fluoropolymer, the crystals are easily peeled off from the surface. Of course, any suitable alternative coating material may be used on the outer surface of the front plate 4054 or the back plate 4056.
In yet another alternative embodiment, the surfaces of the front plate 4054 or the back plate 4056 need not be coated if either plate is made of a suitable material. For example, if the front and back plates 4054, 4056 are constructed of a high density plastic (e.g., an acetyl copolymer), the material itself will provide the same performance against clumping of contrast agent as the fluorine-containing copolymer coated on aluminum.
As shown in fig. 56 and 57, the front plate 4054 includes a hole 4058 therethrough. The lip 4060 extends around the perimeter of the aperture 4058 through the front plate 4054. In a preferred embodiment, when syringe 4012 engages release/connector mechanism 4010, flange 4042 and lip 4060 engage one another to minimize any leakage of contrast media through aperture 4058 into the interior of connector mechanism 4010. Figure 72 particularly illustrates the engagement between the lip 4060 and the flange 4042. Alternatively, as will be appreciated by those of ordinary skill in the art, the syringe 4012 is configured to not include the flange 4042. In addition, alternative structures are provided on the injector 4012 or the front plate 4054 to minimize access to the interior of the release/connector mechanism 4010.
In the embodiment illustrated and described in figures 55-78, the flange 4042 may also serve an additional function as a mechanical stop when it engages the front face 4020 of the front plate 4054.
Such contrast media used in the syringe 4012 typically interferes with the operation of the connector/release mechanism 4010. Accordingly, it is preferable to include some structure, such as flange 4042 (see FIG. 79), that minimizes the entrance of contrast media into the interior of connector mechanism 4010. However, even if blocked by some contrast agent (which is often unavoidable), it is believed that the connector/release mechanism 4010 is able to function.
Flexible ring 4026 is a generally oval member that is disposed behind front plate 4054 of release/attachment mechanism 4010. Flex ring 4026 is made of an acetal copolymer or any other suitable material. As best shown in fig. 66 and 67, flexible ring 4026 includes a straight or flat portion 4062 on either side integrally connected to two arcuate portions 4064. The strut 4066 extends from the back plate 4056 substantially at the midpoint of the arcuate portion 4064. As shown, flexible ring 4026 includes a hole 4068 therethrough. As shown in FIG. 66, a chamfered surface 4082 is provided on a front face 4080 of the flex ring 4026. As shown below, the chamfered surface 4082 facilitates insertion of the trailing end 4022 of the syringe 4012 and the ridge 4044 therethrough.
In the embodiment shown in fig. 56 and 57, struts 4066 extending rearwardly from flexible ring 4026 have bearings 4070. (flexible ring 4026 is shown in detail in FIGS. 66 and 67). The bearing 4070 is preferably a composite bearing (e.g., metal and plastic) having inner and outer races with a ball bearing disposed between the races. Alternatively, the bearing 4070 is a plastic member that surrounds the post 4066 and rotates relative thereto. The bearings 4070 engage slots or cam tracks 4072 on the rotating ring 4028. However, as those skilled in the art will appreciate, bearings are not necessary for operation of the release/connector mechanism 4010. Fig. 114 illustrates another embodiment of the present invention in which bearings 4070 are omitted to simplify the construction of the connector mechanism 4402 and thereby reduce its manufacturing cost.
The rotating ring 4028 is disposed in the housing 4024 behind the flexible ring 4026 and includes two slots or cam tracks 4072 on the front face 4074 thereof. As best shown in fig. 61, 68, and 69, cam track 4072 is shaped such that the diameter of outer surface 4074 increases along its arc from a point 4076 that is closest to the center of rotating ring 4028 to a point 4078 that is farthest from the center of ring 4028. Slots 4072 engage posts 4066 through bearings 4070 and engage rotating ring 4028 while injector 4012 is rotating (e.g., so that injector 4012 is not engaged with release/connector mechanism 4010), forcing posts 4066 apart to extend flexible ring 4026 in the direction indicated by arrow 4084 in fig. 66 and 67. As shown, flexible ring 4026 has a hole 4068 through its center to receive or pass through the rear end 4022 of syringe 4012.
The rotating ring 4028 is shown in detail in FIGS. 68 and 69 and is disposed within a recess or recess 4090 formed in the front face 4088 of the back plate 4056. (figures 70 and 71 show the back plate 4056 in detail). The back plate 4056 has a hole 4092 therethrough to receive the back portion 4022 of the syringe 4012. The rotating ring 4028 is disposed in the recess 4090 such that the ring 4028 is free to rotate therein. The back plate 4056 has a back face 4094 which is shown in fig. 57 and 71.
As shown in fig. 57, 58, and 64, the back face 4096 of front plate 4054 includes a notch or recess 4098, the recess 4098 having substantially the same shape as flexible ring 4026. Likewise, the recess 4098 includes two straight or flat portions 4100 and two curved portions 4102. (see, e.g., FIGS. 58 and 64). The two grooves 4104 in the back face 4096 of the front plate 4054 are positioned approximately at the center point of the arcuate portion 4102. Recesses 4104 receive posts 4066 and the associated structure connecting posts 4066 to flexible ring 4026. Notches 4098 are shaped larger than flexible ring 4026, while distance 4106 between grooves 4104 is larger than distance 4108 between struts 4066 (see fig. 66 and 67) in the relaxed state. Recesses 4104 help prevent flexible ring 4026 from rotating within housing 4024 and allow flexible ring 4026 to expand when rotating ring 4028 is rotated.
The operation of release/attachment mechanism 4010 is illustrated and described in connection with fig. 74-78 and 55-73.
As shown in fig. 74-76, the rear end 4022 of the syringe 4012 is inserted into the connector housing 4024 through an aperture or port 4058 in the front plate 4054, in the direction indicated by arrow 4110. Flexible ring 4026 is located in a notch 4098 formed in the back face 4096 of front plate 4054 such that posts 4066 engage recesses 4104. Thus, when angled surface 4046 of ridge 4044 of syringe 4012 engages angled surface 4082 on flexible ring 4026, ridge 4044 pushes flexible ring 4026 in direction 4084 (as shown in fig. 66 and 67) to expand it from relaxed distance 4108 (see fig. 77) to extended (or tensioned) distance 4106 (see fig. 58 and 78). This feature is illustrated in fig. 75. Flex ring 4026 opens in the direction indicated by arrow 4112.
As shown in fig. 76, when ridges 4044 clear the trailing edge of flex ring 4026, the resilient nature of flex ring 4026 causes flex ring 4026 to return to its relaxed state in the direction of arrow 4114. As flex ring 4026 returns to its relaxed state, shoulders 4048 of ridges 4044 engage the trailing edge of flex ring 4026. Syringe 4012 is thereby held in place by flexible ring 4026 and cannot be axially removed from release/connector mechanism 4010. When the flexible ring 4026 returns to its relaxed state, it preferably provides an audible "click" to indicate to the operator that the syringe 4012 has been mounted on the injector.
As described below, removal of the syringe from the release/connector mechanism 4010 preferably requires 1/4 or approximately one-quarter turn of the syringe 4012. This operation is shown and described in connection with fig. 77, 78 and 55-73.
As shown in fig. 60 and 73, once flexible ring 4026 engages syringe 4012, protrusions 4050 engage two grooves 4052 in rotating ring 4028. Fig. 77 shows a cross-sectional view of the engagement of syringe 4012 and flexible ring 4026 (shown in a fully oval configuration for convenience). In a preferred embodiment, as the syringe 4012 is rotated approximately a quarter of a turn in the counterclockwise direction, the protrusions 4050 engaging the grooves 4052 force the rotational ring 4028 to also rotate in the same direction by substantially the same amount. While it is preferred that mechanism 4010 be designed to release syringe 4012 by rotating counterclockwise, it is specifically contemplated that mechanism 4010 can also be adapted to release syringe 4012 by rotating clockwise. (it should be noted that the reference to one quarter turn herein does not mean exactly one quarter turn-the term "one quarter turn" means around one quarter turn, preferably in the range of 45 to 90 degrees from the rest position of injector 4012. alternatively, any suitable range of rotation may be used to facilitate disengagement of injector 4012 from mechanism 4010.)
Because posts 4066 (with bearings 4070) of flexible ring 4026 engage and are positioned within cam tracks 4072 on rotating ring 4028, rotation of ring 4028 causes flexible ring 4026 to change from its relaxed (i.e., syringe-engaged) state to its extended (i.e., syringe-disengaged) state. As post 4066 moves along cam track 4072 from innermost position 4076 to outermost position 4078, flex ring 4026 is stretched from slack distance 4108 to extended distance 4106 (in the direction of arrow 4112) where shoulder 4048 of injector 4012 no longer engages the trailing edge of flex ring 4026. Subsequently, syringe 4012 disengages from flexible ring 4026 and mechanism 4010 and is axially removed therefrom. Upon removal of syringe 4012 from mechanism 4010, the spring force of flexible ring 4026 causes posts 4066 to move along cam track 4072 from outermost position 4078 to innermost position 4076, thereby restoring flexible ring 4025 to its relaxed state to receive a new syringe. Additionally, when the syringe 4012 disengages the flexible ring 4026, the operator preferably hears a second audible "click" to indicate that the syringe 4012 has disengaged the engagement mechanism 4010 (and thus the injector).
In yet another embodiment, a return spring (not shown) is added to housing 4024 to assist in restoring the stationary state of flexible ring 4026 and rotating ring 4028 after syringe 4012 is disengaged from release/connector mechanism 4010. In this embodiment, a return spring is connected between the rotating ring 4028 and the housing 4024 (the front plate 4054 or the rear plate 4056). The return spring would be even more useful if the elements of the syringe release/connector mechanism 4010 become clogged with contrast media during a medical procedure (and thus over time after multiple uses).
As discussed above, fig. 79 illustrates the efficacy of flange 4042, which is used to prevent contrast media in syringe 4012 from entering the syringe interface and injector of the present invention.
The present invention also includes the structure of the first preferred embodiment of the injector piston and syringe plunger interface assembly 4200 for injector 4014 that can engage the plunger in syringe 4012 regardless of the orientation of the syringe in release/connector mechanism 4010 or the orientation of the plunger in syringe 4012. Fig. 80-109 illustrate the piston/plunger assembly 4200 and its operation.
The piston/plunger assembly 4200 is movably positioned in axial relation to the injector 4014 and the syringe 4012. As shown in fig. 85 and 86, the piston 4202 includes a rearward end 4204 and a forward end 4206. The piston 4202 also includes an elongate shaft 4208 extending between the rearward end 4204 and the forward end 4206. The rearward end 4204 of the piston 4202 is connected to a propeller or drive train in the injector 4014. The pusher can be any type of pusher suitable for moving the plunger 4202 axially into and out of the injector 4014, including a combination of an electric motor and drive train.
As shown in fig. 80-82, a piston sleeve 4210 surrounds the shaft 4208 of the piston 4202. Piston sleeve 4210 is free to move relative to piston 4202. In other words, piston sleeve 4210 is not connected to piston 4202. The piston sleeve 4210 is substantially a cylindrical tube having a front end 4212 and a rear end 4214. (see FIG. 87 for an enlarged piston sleeve 4210).
A collar 4216 is disposed at the front end 4212 of the piston sleeve 4210. As shown in fig. 88-90, collar 4216 includes a piston 4202 that passes through aperture 4218. An annular flange 4219 is provided on the rear side 4220 of the collar 4216 for engaging the front end 4212 of the piston sleeve 4210. A second annular flange 4222 is provided on the front surface 4224 of the collar 4216. The annular flange 4222 engages a plunger cap 4226, which is generally depicted in fig. 97-100.
Plunger cap 4226 has a base portion 4230 extending outwardly from its base (see fig. 97-100). Base portion 4230 is connected to a frustoconical portion 4232 that tapers inwardly toward the centerline of plunger cap 4226. An annular groove 4234 is disposed in plunger cap 4226 adjacent to frustoconical portion 4232. Slots 4236 are disposed in annular groove 4232 to retain backup ring clip 4238. A top portion 4240 of plunger cover 4226 extends upwardly from annular groove 4234. The top 4240 is conical and terminates in a rounded tip 4242. As shown in fig. 98, plunger cap 4226 is substantially a hollow body defining an interior volume 4244.
The forward end 4206 of the piston 4202 extends into the interior volume 4244 of the plunger cap 4226. As shown in fig. 107 and 108, front end 4206 of piston 4202 is coupled to clip extender 4246. Clip extender 4246 is attached to forward end 4206 of piston 4202 by any suitable means, such as a screw (not shown) disposed in a hole 4248 through the center of clip extender 4246. (details of clamp extender 4246 are provided in fig. 91-93.)
Clamp extender 4246 has a top surface 4250 and a bottom surface 4252. Clip extenders 4246 taper inwardly from top surface 4250 to form a frustoconical portion 4254. Cylindrical portion 4256 extends from frustoconical portion 4254 to bottom surface 4252. As shown in fig. 107 and 108, clip extender 4246, when coupled to front end 4206 of piston 4202, forms a T-shaped structure with piston 4202.
As shown in FIGS. 83, 84, 94-96, 107 and 108, the support ring clip 4238 passes through a slot 4236 in an annular groove 4234 of the plunger cap 4226. When the piston/plunger assembly 4200 is moved or retracted in a rearward direction (into the injector 4014), the support ring grippers 4238 are designed to extend outward from the annular groove 4234. As shown in FIGS. 94-96, the support ring clamp 4238 has a body 4258 that is L-shaped in cross-section. On the inner edge 4260, the support ring clamp 4238 is provided with a beveled surface 4262 which engages a frustoconical surface 4254 on the clamp extender 4246. As clip extender 4246 moves in the direction of injector 4014 (which is indicated by arrow 4264 in fig. 108), support ring clip 4238 moves outwardly from plunger cap 4226 in the direction of arrow 4266 (also shown in fig. 108).
A rubber cap 4268 (shown in detail in figures 105 and 106) is normally assembled with and located within the syringe 4012. Movement of the rubber cap 4268 pushes the liquid contained in the syringe 4012 out through the discharge end 4036 and into the patient. The rubber cap 4268 includes a conical top portion 4270 having a rearwardly extending, generally cylindrical portion 4272. The cylindrical portion 4272 includes any number of ridges 4274 and grooves 4276 as required by the particular application to ensure that liquid does not pass through the plunger and seep out of the syringe 4012, such as during injection.
The interior of the rubber cap 4268 is hollow and therefore has a conical inner surface 4278. Additionally, at the bottom end 4280, a lip 4282 is provided which defines a circular opening 4284 into the interior of the rubber cap 4268. Lip 4282 is designed to engage with rubber cap support ring 4286.
Fig. 101-104 show in detail the rubber cap support ring 4286, which is made of a suitable plastic material. Rubber cap support ring 4286 engages lip 4282 on the interior of rubber cap 4268 and provides additional rigidity to rubber cap 4268. The rubber cap support ring 4286 comprises an annular ring 4288 at its base 4290. Above the ring 4288 is provided a groove 4292 for engaging the lip 4282 of the rubber cap 4268. A frusto-conical portion 4294 extends upwardly from the slot 4292 and engages in the inner surface 4278 of the rubber cap 4268. Hole 4296 passes through rubber cap support ring 4286. The inner surface of rubber cap support ring 4286 includes a lip 4298 having a chamfered surface 4300. Lip 4298 may serve as a location to engage support ring clamp 4238.
In another embodiment of rubber cap 4268, the rubber cap support ring 4286 may be eliminated entirely. Fig. 110-113 shows another embodiment of a rubber cover, indicated at 4306. Since the rubber cover 4306 does not include the rubber cover support ring 4286, the rubber cover 4306 is thicker in cross section than the rubber cover 4268. Thus the gripper 4238 engages the rubber cover 4306, which includes a lip 4308 on an inner surface, at least during the retracting operation of the injector 4014.
The rubber cover 4306 has substantially the same shape as the rubber cover 4286. The rubber cover 4306 includes a conical top 4310 having a rounded tip 4312. At its lower end 4314, the rubber cover 4306 includes three ribs 4316 and two slots 4318 located along the cylindrical portion. The interior of the rubber cover 4306 defines an interior volume 4320 having tapered sides 4322. Rubber cover 4306 is thicker than rubber cover 4286 to provide it with increased strength and sealing capability (i.e., to seal the interior of syringe 4012).
The operation of the piston/plunger assembly 4200 will now be described in conjunction with fig. 107-109. The operation of the piston/plunger assembly 4200 is substantially the same if a rubber cap 4268 (together with a rubber cap support ring 4286) or rubber cap 4306 is employed in the syringe 4012.
When the operator of injector 4014 wishes to advance or push forward on piston/plunger assembly 4200, he will press one of buttons 4302 on injector 4014 to cause piston 4202 to move forward. Movement of the piston 4202 in a forward direction will push the rubber cap 4268 in a forward direction. Since forward movement of the rubber cap 4268 in the forward direction does not require any connection between the piston assembly 4202 and the rubber cap 4268, the two are only in close fitting engagement with each other. However, if the injector operator wishes to retract or move the rubber cap 4268 in the rearward direction, the piston/plunger assembly 4200 must grasp the rubber cap 4268 in order to pull the rubber cap toward the injector 4014.
To capture rubber cap 4268 (and rubber cap support ring 4286 including its association), grippers 4238 extend outwardly to capture lip 4298 of rubber cap support ring 4286. If another rubber cover 4306 is used, the clip 4238 engages the lip 4308. The engagement of lip 4298 (or lip 4308) with clip 4238 will be described below.
As described above, piston sleeve 4210 is not connected to piston 4202. Instead, it may move freely (in an axial direction) relative to the piston 4202. In the injector 4014, there is an O-ring 4304 that engages the outer surface of the piston sleeve 4210. (see fig. 107 and 108.) thus, as the piston 4202 retracts into the injector 4014, the piston sleeve 4210 undergoes frictional engagement with the O-ring 4304, which tends to hold the piston sleeve 4210 in place. In other words, when the piston 4202 is retracted in the rearward direction, the ring 4304 biases the piston sleeve 4210 in the forward direction.
Since piston 4202 is connected to clip extender 4246, as piston 4202 moves into injector 4014, clip extender 4226 also moves into the injector. However, the piston sleeve 4210, collar 4216 and plunger cover 4226 are elements connected to each other, which are biased in a forward direction by the O-ring 4304. Thus, upon actuation, piston 4202 and clip extender 4246 move rearward relative to piston sleeve 4210, collar 4216 and plunger cap 4226. The frustoconical portion 4254 of clip extender 4246 is then caused to engage the chamfered region 4262, forcing clips 4238 outwardly through slots 4236 in plunger cap 4226 (as indicated by arrow 4266 in fig. 108) and into engagement with lip 4298 (or lip 4308) of support ring 4286. To hold the gripper 4238 in place, a rubber boot (not shown) is placed over the plunger cap 4226. The rubber sheath may also assist in preventing contrast from entering plunger cap 4226 through slot 4236.
Thus, with this configuration, rubber cap 4268 is only connectively engaged with plunger 4202 when plunger 4202 is retracted or moved in a rearward direction into injector 4014. At rest or when moved forward, rubber cap 4268 does not engage plunger 4202 to facilitate disengagement of syringe 4012 from syringe interface 10.
As can be appreciated, the piston/plunger assembly 4200 of the present invention is preferably not specifically oriented. That is, engagement between piston 4202 and plunger cover 4268 may occur regardless of the orientation of the plunger in syringe 4012 and/or the orientation of the plunger relative to piston 4202. In conjunction with a suitable syringe interface of the present invention, an injector and syringe system are provided that do not require the operator to position the syringe in any particular manner relative to the injector in order to mount the syringe thereon. The present invention, in at least one aspect, thereby improves and facilitates syringe assembly and mounting on an injector.
Fig. 114 illustrates another embodiment of a release/connector mechanism 4402 of the present invention. Here, flex ring 4026 does not include bearings 4070 around struts 4066. This simplifies the construction of the connector mechanism 4402, as described above. Here, release/link mechanism 4402 operates in the same manner as link mechanism 4010, except that stanchion 4066 directly engages cam track 4072. For convenience, screws 4404 are shown holding the front plate 4054 to the rear plate 4056.
Fig. 115 illustrates yet another embodiment of a syringe coupling/connector mechanism 4406 of the present invention. Here, the rotating ring 4028 is omitted entirely. In this embodiment, grooves 4408 are provided on the inner surface of the flexible ring 4410 for engaging with protrusions 4412 (see fig. 117) on the syringe 4414. The struts 4416 extend from upper and lower positions of the flexible ring 4410 and engage slots 4418 in the back plate 4420 (or in the front plate (not shown in the figures)). Figure 117 shows a cross-sectional view of the syringe 4414, as the syringe 4414 is rotated (preferably in a counter-clockwise direction), the tabs 4412 rotate the flexible ring 4410 to move the struts 4416 in the slots 4418, stretching the flexible ring 4410 and releasing the syringe 4414. For the sleeve protrusions 4412 engaging the grooves 4408, the protrusions 4412 are positioned between the ridge 4044 and the flange 4042. To assess the differences between the two alternative designs, syringe 4414 is shown adjacent syringe 4012 (see fig. 116 and 117).
Fig. 118 shows an alternative embodiment of three different shapes of slots for the rotating ring 4028 or the flexible ring 4410. It should be noted that different shapes for the grooves 4052 may be used with any of the alternative embodiments of the rotating or flexible rings described herein. First, in embodiment #1, a groove 4052 is shown, which is the same as the groove described in fig. 59. In embodiment #1, the groove 4052 is a semi-cylindrical recess on the inner surface of the rotating ring 4028. Embodiment #2 shows a groove 4052' having a triangular shape. Embodiment #3 shows a U-shaped channel 4052 ". It should be readily understood by one of ordinary skill in the art that the grooves 4052, 4052', 4052 "can be any suitable shape that engages the projections 4050 or their equivalent.
One possible disadvantage of the previously described embodiment of the syringe engagement/connector mechanism of the present invention is made apparent by the illustrations of fig. 77 and 78. There, it can be seen that the flexible ring 4026 engages the ridges 4044 on the syringe 4012 only at two locations 4400 around the circumference of the syringe 4012. While this may hold syringe 4012 in place in most cases, high pressure must be applied in some cases to inject the contrast media in syringe 4012 into the patient. Under the application of high pressure (e.g., 1000 psi or more), the two areas 4400 may not provide sufficient area of contact with the ridges 4044 to hold the syringe 4012 securely in the release/connector mechanism 4010. In these cases, it is also preferable to contact a substantial portion of the ridge if flexible ring 4026 is not able to contact all of ridge 4044 surrounding syringe 4012.
Figure 119 illustrates an embodiment of a release/connector mechanism 4440 of the present invention which provides a flexible ring 4450 which is circular in shape to engage a substantial portion of a ridge 4044 along the circumference of the syringe 4012. The flexible ring 4450 is almost a complete circle having an inner diameter that is just larger than the outer diameter of the syringe body 4030 in the relaxed state. The flexible ring 4450 includes two posts thereon, one post 4452 engaging a hole 4456 in a slot 4460 in the front plate 4462 and the other post 4454 fitting into a hole 4458 in the rotating ring 4464. The rotating ring 4464 is fitted in a notch (not shown in the figure) of the rear plate 4466. Screw 4468 may be used to assemble release/connector mechanism 4440.
As with the other embodiments, the syringe 4012 is inserted through a hole 4470 in the front plate 4462. When the ridge 4044 of the syringe 4012 passes over the flexible ring 4450, the flexible ring 4450 snaps into place around the syringe 4012 and provides an audible "click". In place, the protrusions 4050 on the syringe 4012 engage the grooves 4472 on the inner surface of the rotating ring 4464.
To disengage the syringe 4012 from the release/connector mechanism 4440, the syringe 4012 is rotated approximately one-quarter turn. Rotation of the syringe 4012 causes the rotation ring 4464 to rotate in the direction of arrow 4474. As the rotation ring 4464 rotates, pressure applied to the strut 4454 causes the flexible ring 4450 to enter a tensioned state at a location having a larger inner diameter. Upon application of sufficient force to the flexible ring 4450, the syringe 4012 will be released and provide an audible "click" while released.
In the previous embodiment, the flexible loop was shown as a monolithic structure. However, the flexible ring may be constructed as several pieces connected to each other or to the housing in some manner for releasing/connecting the mechanism so that the separate elements also have a relaxed and tensioned state (as in the one-piece construction).
Figure 120 shows a possible embodiment of a two-piece "flex ring". As shown, the syringe engagement/connector mechanism 4480 includes a front plate 4482 that is designed similar to the front plate 4054 (shown in FIGS. 56 and 57). The front plate 4482 includes a notch 4484 in its rear surface sized to receive a flexible ring 4486. The front plate 4482 has a hole 4488 therethrough. It also has slots 4490 that receive posts 4492 on flexible ring 4486.
Flexible ring 4486 is shaped similarly to flexible ring 4026. As shown, the flexible loop 4486 has two separate arcuate pieces 4494, 4496 that are joined together along a seam 4498, 4500 on either side. Two springs 4502, 4504 are located on either side of the flexible ring 4486 that bias the flexible ring 4486 to a relaxed position around the syringe once the syringe 4012 is inserted therebetween.
The rotating ring 4506 is positioned behind the flexible ring 4486. The rotating ring 4506 has a hole 4508 therethrough, and a plurality of grooves 4510 are provided in the inner surface thereof. The rotating ring 4506 is not directly connected to the flexible ring 4486 (as with the other embodiments). Instead, the swivel ring 4506 includes two struts 4512, 4514 that extend from the back side through a back plate 4516. As with the other embodiments, the rotating ring 4506 is positioned in a notch (not shown) on the inner surface of the back plate 4516.
Two semi-circular arms 4518, 4520 are positioned behind the back plate 4516. Each arm includes a post 4522, 4524 that engages a post 4492 on flexible ring 4486. Each arm also includes a groove 4526, 4528 that engages a post 4512, 4514, respectively, on the rotating ring.
The operation of the release/connector mechanism 4480 is substantially the same as the previous embodiment. As the syringe 4012 is inserted through the flexible ring 4486, the two segments 4494, 4496 of the flexible ring 4486 resiliently separate and come into tension until the ridge 4044 on the syringe 4012 clears the trailing edge of the segments 4494, 4496 of the flexible ring 4486. When the ridge 4044 passes over the flexible ring 4486, the springs 4502, 4504 return to a relaxed state and the tab segments 4494, 4496 engage the injector 4012. Segments 4494, 4496 preferably provide an audible "click" when they return to a relaxed state.
To remove the syringe 4012 from the release/connector mechanism 4480, the syringe 4012 is rotated approximately one-quarter turn. As before, injector 4012 is provided with tabs 4050 which engage slots 4510 on the inner surface of rotary ring 4506. As the spin ring 4506 rotates, the arms 4518, 4520 move outwardly from the relaxed position to the tensioned position and apply pressure to the posts 4492, causing the segments 4494, 4496 of the flexible ring 4486 to spread apart. Once the syringe is rotated a sufficient distance, the segments 4494, 4496 are sufficiently separated from one another to release the syringe 4012, preferably with an audible "click".
Fig. 121 and 122 illustrate yet another embodiment of a release/connector mechanism 4550 in accordance with the principles of the present invention. Here, instead of a flexible ring, four segments 4552, 4554, 4556, 4558 are provided around the circumference of a common bore 4560 through the connector mechanism 4550. The four segments 4552-4558 are biased by any suitable mechanism. For example, segments 4552 and 4558 are connected to the spin ring by arms in a manner similar to connector mechanism 4480.
The present invention also provides injectors and injector systems having certain "automated" or "automation" features to facilitate their operation. For example, the injector and injector system of the present disclosure provide one or more of the following functions: "self-advancing", "self-engaging", "self-filling", "priming", and "self-retracting". Each of these functions, and the attendant advantages and benefits thereof, will be described in detail below in connection with empty, pre-loaded and/or pre-filled syringes. As is known in the art, an "empty" syringe is a syringe that does not contain fluid when mounted on an injector for use in an injection procedure. Empty syringes are generally divided into two categories: syringe of the "plunger-back" type and syringe of the "plunger-forward" type. A plunger-back syringe is a syringe having a plunger initially at its rear or proximal end. A plunger-forward syringe is a syringe having a plunger initially at its forward or distal end. A "preloaded" syringe is an empty syringe that is filled with fluid prior to an injection procedure (e.g., by hand or by drawing fluid into the syringe using an injector), and then stores the fluid in the injector during the injection procedure for subsequent use. A "pre-filled" syringe is a syringe that is filled with fluid prior to delivery to a user.
In a preferred embodiment, the injector and injector system of the present invention are adapted to automatically identify, for example, the type, size, contained fluid (if applicable), and configuration of the syringe mounted thereon. Suitable sensors and encoding devices discussed above and in U.S. Pat. No.5,383,858 and PCT publication No. WO 99/65548, both of which are incorporated herein by reference, can distinguish between different syringes used on an injector (e.g., an empty, pre-loaded or pre-filled syringe). These detection schemes or suitable alternatives known in the art may also be used to implement the automated features discussed below.
The "auto-engage" feature may cause the injector to automatically advance its drive piston to engage the syringe plunger when the syringe is mounted or attached to the injector. In a preferred embodiment, the automatic engagement feature occurs without operator intervention. This feature is particularly useful for pre-loaded and pre-filled syringes, which typically have a plunger located somewhere in the syringe barrel (except at its proximal and distal ends), as well as plunger-forward syringes. In the case of pre-filled syringes, the auto-engagement feature automatically connects the injector piston and syringe plunger for priming and subsequent injection of the syringe (and associated tubing). For a plunger-forward injector, an auto-engage feature engages the piston with the plunger for subsequent plunger retraction and aspiration of fluid (e.g., contrast media) into the injector.
The "self-advancing" feature is related to the automatic engagement feature and is considered to be one or a subset of the automatic engagement feature. The auto-advance feature automatically advances the plunger of a plunger-back syringe (i.e., by the drive piston of the injector) to the distal end of the syringe after the syringe is mounted on the injector. Operation of this feature may expel air from an empty plunger back-up syringe and position the syringe plunger in a position that is then retracted to draw fluid (e.g., contrast media) into the syringe for the injection procedure. In a preferred embodiment, the injector detects the mounting or assembly on the syringe and automatically advances the piston to drive the plunger to the distal end of the syringe without operator intervention. Of course, this feature is typically used only with empty syringes (as opposed to pre-loaded or pre-filled syringes) to prevent fluid from being expelled therefrom.
As discussed above, in a preferred embodiment, the injector and injector system of the present invention are adapted to automatically distinguish between, for example, an empty syringe and a preloaded syringe. Because the preloaded syringe is an empty syringe that is filled and stores fluid prior to the injection procedure, and further because the operator may or may not load the empty syringe with fluid for storage prior to the injection procedure as needed by the application, it is difficult for the injector to distinguish between an empty plunger rearward syringe and a preloaded syringe.
One possible arrangement to address this problem is to assemble a plunger-backed syringe using a plunger positioned at a location rearward of the maximum fill capacity of the syringe. As will be appreciated, this arrangement will result in a preloaded syringe having a plunger positioned at some equal or forward location of the maximum fill volume of the syringe (after loading with fluid). In operation, after a syringe is placed on the injector and an empty syringe is identified, the auto-engagement feature will drive the piston forward to engage the syringe plunger. If the piston engages the syringe plunger at a location behind the maximum filling capacity of the syringe, the injector may identify the plunger-back syringe that has been mounted thereon, the auto-advance feature may drive the plunger to the distal end of the syringe to expel air therefrom, and place the plunger in position for drawing fluid into the syringe. On the other hand, if the piston engages the syringe plunger at an equal or forward position of the maximum fill capacity of the syringe, the injector may identify a pre-loaded syringe that has been mounted thereon. Of course, the auto-advance feature cannot be activated (i.e., prevents the piston from advancing the plunger to the distal end of the syringe, thereby expelling the pre-loaded fluid out of the syringe) when the injector determines that a pre-loaded syringe has been mounted thereon.
The "auto-fill" or "auto-load" feature may cause the injector to automatically retract the syringe plunger (i.e., with the injector piston) to introduce or draw a defined amount of fluid (e.g., contrast media) into the syringe. The auto-fill feature preferably occurs without operator intervention, thereby allowing the operator to perform other tasks (e.g., programming a scanner or injector, placing a patient on a scanning table, inserting a catheter into a patient) while the syringe is being filled with fluid. Of course, prefilled or preloaded syringes that already contain fluid typically do not require this feature.
In a preferred embodiment, the auto-fill feature further includes a "trapped air reduction" feature to reduce the amount of air drawn into the syringe during the fluid intake process. During the aspiration process, features such as auto-fill facilitate the injector piston retracting the syringe plunger to introduce fluid into the syringe. Typically, air is drawn into the syringe with the fluid, for example, when the absorption flow rate is sufficiently great. To reduce the amount of air drawn into the syringe, the trapped air reduction feature causes the movement of the injector piston (i.e., slightly advancing the injector piston) to reverse one or more times during the aspiration process. By reducing the amount of air drawn into the syringe during the filling operation, the amount and size of air bubbles formed in the syringe, and consequently the time required to expel air out of the syringe and connecting tube (i.e., priming system), will be reduced, resulting in a reduced likelihood of inadvertently injecting air.
The "auto prime" feature may enable the injector to automatically prime the fluid path (i.e., the syringe and connecting tube) prior to the injection process. The volume of fluid contained in the connector tubing used with the syringe is preferably preprogrammed into the injector. For example, the 60' low pressure connection tube ("LPCT") provided by Medrd corporation, the assignee of the present invention, for use with its disposable syringes typically contains about 2.78 milliliters of fluid. Alternatively, the operator programs the volume of fluid contained in the connector tubing into the injector manually.
As will become apparent, the automatic priming feature is functionally dependent in some way on the automatic filling feature described above. When the syringe is filled with fluid (i.e., via the auto-fill feature), the injector automatically compensates for the connector tubing by adding its corresponding fluid volume to the fluid volume that the operator desires to draw into the syringe for the injection operation. For example, if the operator desires to fill a syringe with 150 milliliters of fluid for an injection procedure, the auto-fill feature would compensate for the connector tube's fluid capacity by automatically adding 2.78 milliliters of fluid (e.g., for a 60' LPCT) to bring the total volume drawn into the syringe to 152.78 milliliters. After the syringe is filled with fluid, the auto-prime feature then causes the injector piston to advance the syringe plunger to a degree sufficient to allow air to exit the syringe and connector tubing system, preferably without the need for operator prompting. Once the autoperfusion effect is performed, fluid will be present at the patient end of the connector tube (i.e., the end connected to the catheter).
As can be appreciated, the automatic priming feature will save the operator time and reduce the amount of fluid wasted. By automatically compensating for the fluid contained in the connector tube, the operator need not be vigilant regarding the progress of fluid exiting the syringe through the connector tube in order to stop the advancement of the piston before a greater amount of fluid exits the end of the connector tube. Also, because the operator of some conventional injectors advances the plunger quickly to reduce the time required to prime the syringe and tubing system, a larger amount of fluid is typically expelled out of the end of the connector tubing before the operator stops the advancement of the plunger. If a sufficient amount of contrast media is expelled, the syringe (and subsequently the syringe and tubing system) will have to be refilled to ensure that it contains a sufficient amount of fluid for the desired injection procedure.
While the auto-prime feature is preferably used with empty syringes filled with fluid by the aspiration process of the injector (i.e., pre-unfilled and pre-unloaded syringes), the auto-prime feature may also be used with pre-filled and pre-loaded syringes.
The "auto-retract" feature allows the injector to automatically retract the injector plunger after the syringe is removed or disconnected from the injector. At the end of the injection procedure, the injector piston and syringe plunger are typically located at the distal end of the syringe. Thus, as described above and in U.S. Pat. Nos. 5,383,858 and 5,300,031 (the contents of both of which are incorporated herein by reference), the syringe plunger typically extends from the front of the injector (or in a pressure jacket attached to the front of the injector) after the syringe is detached from the injector. Especially in the case of plunger-backed syringes, pre-loaded syringes and pre-filled syringes, the piston must typically be retracted and a new syringe mounted on the injector for the next injection procedure. To save the operator time to retract the plunger, the auto retract feature automatically retracts the plunger after the injector detects that the syringe has been removed therefrom (e.g., after the injection procedure), leaving the injector plunger in place to receive a new syringe. If a plunger-forward syringe is used on the injector, the auto-retracting feature will fail to prevent unnecessary and/or redundant piston movement. The auto-retracting feature may be disabled manually by an operator or automatically by an injector. For example, when a plunger-forward syringe is installed on and identified by the injector, the injector may automatically initiate a default setting to disable the auto-retraction feature of subsequent syringes until an operator initiates an override or until the system detects pre-filling, pre-loading, or attachment of a plunger-rearward syringe. When the injector detects a pre-filled or pre-loaded syringe, the system may compensate for any remaining air remaining in the syringe by adjusting the amount of priming to be administered. For example, if a pre-filled syringe typically contains about 1.2 milliliters of air or "dead space" and is connected to a 60' LPCT (containing about 2.78 milliliters of fluid), the injector system will prime about 3.97 milliliters from the syringe and connecting tube system.
As will be appreciated, the above-described automated features may be used independently or in conjunction with one another to facilitate use of the injector, depending on the needs of the operator. For example, the automatic feature described above may be used with a plunger-backed syringe in the following manner. When the operator mounts the plunger-back syringe on the injector, the auto-advance feature advances the syringe plunger to the distal end of the syringe (i.e., forces air out of the syringe and places the plunger in position to aspirate fluid). The auto-fill feature then draws a predetermined amount of fluid into the syringe, depending on the amount the operator needs for the injection process, preferably to compensate for the fluid capacity of the connector tubing. The auto-prime feature then automatically advances the injector piston and syringe plunger to remove air from the syringe and connecting tubing system. Subsequently, after the injection procedure is completed and the syringe is removed from the injector, the auto-retract feature retracts the injector piston, placing the injector in position for the next injection procedure of a plunger-backed, pre-loaded, or pre-filled syringe.
As another example, the auto feature may be used with a pre-filled syringe or a pre-loaded syringe in the following manner. When the operator places the prefilled syringe or the preloaded syringe on the injector, the auto-engagement feature advances the injector piston into the syringe to engage or contact the syringe plunger. The auto-prime feature then advances the piston and plunger to allow air to vent and thereby prime the syringe and connector tubing system. Subsequently, after the injection procedure is completed and the syringe is removed from the injector, the auto-retract feature retracts the injector piston, placing the injector in position for the next injection procedure of a plunger-backed, pre-loaded, or pre-filled syringe.
As yet another example, the auto feature may be used with a plunger-forward syringe in the following manner. When the operator places the plunger-forward syringe on the injector, the auto-engagement feature advances the injector piston into the syringe to engage or contact the syringe plunger. The auto-fill feature then draws a predetermined amount of fluid into the syringe, depending on the amount the operator needs for the injection process, preferably to compensate for the fluid capacity of the connector tubing. The auto-prime feature then automatically advances the injector piston and syringe plunger to remove air from the syringe and connecting tubing system. Subsequently, after the injection procedure is completed and the syringe is removed from the injector, the auto-retract feature retracts the injector piston (e.g., if an operator override disables the default setting of the auto-retract feature of the plunger-forward syringe), placing the injector in position for the next injection procedure of the plunger-rearward syringe, the pre-loaded syringe, or the pre-filled syringe. If a new plunger-forward syringe is used with the injector (and the operator override does not have a default setting to disable the auto-retraction feature of the plunger-forward syringe), then the auto-retraction feature will not operate and the piston will stay in its extended position for the next syringe.
The injector and injector system of the present disclosure also include additional features that are complementary to one or more of the above-described automation features to further enhance the usefulness of the automation features and to free the operator to perform additional functions. For example, the injector and injector system of the present invention are provided with an attachment means for holding a fluid source, such as a bottle or bag, during an automatic filling action. By maintaining the fluid source during the auto-fill action may eliminate the need for the operator to maintain the fluid source during filling of the syringe, thereby freeing the operator to do additional work in preparation for the injection procedure. Of course, the fluid source attachment device provides benefits to the operator beyond an automatic filling action. For example, if the auto-fill feature is not available on a particular injector, the fluid source attachment device still functions to hold the fluid source during an operator fill operation.
In addition, the injector, syringe and injector system of the present invention are provided with an attachment means for holding the patient end of the connector tubing during priming action (e.g., automatic priming or operator initiated priming). By holding the patient end of the connector tube (preferably in a vertical orientation) to prevent fluid from dripping out of the patient end, the connector tube attachment device frees the operator from doing other work in preparation for the injection procedure. Of course, a variety of other injector operations (injection protocol programming, air checks, etc.) may be implemented between the various automation actions.
The foregoing description and drawings set forth the preferred embodiments of the invention. Of course, numerous modifications, additions and alternative designs will become apparent to those skilled in the art in light of the foregoing teachings without departing from the scope of the disclosure. The scope of the invention is indicated by the following claims rather than by the foregoing description. All changes and modifications that come within the meaning and range of equivalency of the claims are to be embraced within their scope.