US3797488A

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Publication number: US3797488A
Application number: US00270145A
Authority: US
Inventors: A Hurschman; L Udell
Original assignee: Individual
Current assignee: Ampoules Inc
Priority date: 1972-07-10
Filing date: 1972-07-10
Publication date: 1974-03-19
Anticipated expiration: 1991-03-19

Abstract

Description

United States Patent Hurschman et al.

[ AMPOULE APPLICATOR WITH ONE-WAY CLUTCH Inventors: Alfred A. Hurschman, Hudson;

Leslie R. Udell, Cuyahoga Falls, both of Ohio [73] Assignee: Ampoules, Inc., Macedonia, Ohio by said Alfred A. Hurschman Filed: July 10, 1972 Appl. No.: 270,145

[56] References Cited UNITED STATES PATENTS 3,729,003 4/1973 Hurschman 128/218 F 3,094,121 6/1963 Blumenstein et a1... 128/218 D 2,472,116 6/1949 Maynes 128/218 F 3,625,208 12/1971 Frost et al.... 128/173 l-l 2,864,635 12/1958 Lindner 292/305 X 3,502,358 3/1970- Alspaugh et a1. 74/531 X 2,528,002 10/1950 Katzberg 74/531 X 3,298,666 1/1967 Prange 74/531 X FOREIGN PATENTS OR APPLICATIONS 31.681 12/1926 France 128/218 D 958.526 9/1949 France 1.174.719 11/1958 France 128/218 F Primary ExamirierRichard A. Gaudet Assistant ExaminerJ. C. McGowan Attorney, Agent, or Firm-McNenny, Farrington, Pearne & Gordon [451 Mar. 19, 1974 7 1 ABSTRACT An ampoule applicator comprisinlg a hollow, cylindrical body having a chamber at one end for mounting a medicament-containing hypodermic ampoule having a depressible portion for injecting a volume of medicament into a patient. The applicator also includes a spring-biased force-applying member for actuating the ampoule. The force-applying member may be retracted against the bias of the spring by a cocking lever which rotates a pulley at one end of the applicator. A flexible cable is fixed at one end to the forceapplying member and is fixed at its other end to the pulley so that, as the pulley is rotated, the cable is wrapped about the pulley and the force-applying member is retracted. A one-way check mechanism is provided between the force-applying member and the applicator body to permit retraction of the forceapplying member but to prevent movement toward the ampoule during retraction. The one-way check mechanism includes a slot in the applicator body having tapered sidewalls which converge toward the ampoulemounting end of the applicator and a ball which is positioned between the force-applying member and the body. Theball is spring-biased into light frictional Contact with the force-applying member and the converging sidewalls of the slot, and is operable to roll along the slot toward the ampoule-mounting end of the applicator by forward movement of the forceapplying member and into tight frictional contact with the force-applying member to prevent movement of that member toward the ampoule. The force-applying member is released by inserting a pin in the slot to move the ball away from the ampoule-mounting end of the applicator.

19 Claims, 5 Drawing Figures AMPOULE APPLICATOR WITH ONE-WAY CLUTCH BACKGROUND OF THE INVENTION This invention relates to reusable applicators for disposable hypodermic ampoules which are designed to give injections into or below the skin of human beings and animals. These applicators basically comprise an ampoule-receiving chamber at one end thereof and a spring-biased force-applying manner which is retracted or cocked against the force of the spring and locked in that position by a locking mechanism. When the locking mechanism is released, the force-applying member engages a depressible portion of the ampoule to cause medicament to be expressed from the ampoule and into the patient. The ampoule may be a needleless or hypojet injector which performs a hypodermic injection without employing a skin-penetrating needle to effect such injections. A more common ampoule is the contained needle-type having a cylindrical, medicamentcontaining chamber and a plunger closing one end thereof. A hollow needle is fixed to the plunger and is initially contained within such chamber and the other end of the ampoule is sealed by a diaphragm which is adapted to be punctured by the needle when force is applied to the plunger. With the diaphragm in contact with the patients skin, the diaphragm may be punctured by the needle and the medicament may be injected into the patient as a function of the degree of depression of the plunger. Another form of ampoule is the collapsible type shown in U. S. Pat. Nos. 3,094,987 and 3,094,988 to Dunmire.

As was indicated previously, reusable ampoule applicators include a spring which biases the force-applying member toward the ampoule plunger and include a locking device which holds the plunger in a cocked or retracted position. The usual manner of moving the force-applying means to its cocked position is by means of a toggle mechanism or by means of an extension of the force-applying means which projects axially from theapplicator. Examples of the toggle mechanism may be found in U. S. Pat. Nos. 3,094,121, 3,217,712, and 3,236,237. According to these patents, the applicator comprises an elongated, hollow body that houses a spring-biased force-applying member. An external arm or lever and a trigger mechanism are provided to retract the spring-biased force-applying member within the housing into a cocked position against the force of an actuating spring and to release or fire the forceapplying member so that it is forcibly driven by the spring toward the ampoule for actuating it to perform an injection. The external arm or lever is connected to the force-applying member by a toggle linkage which retracts the force-applying member as the lever is swung away from the body of the applicator. The forceapplying member includes two flanged members which are connected by a lost motion mechanism. The spring is positioned between end flanges of these members, and this entire assembly is drawn upwardly by the toggle linkage until a locking detent engages a portion of the sidewall of the hollow body. When the locking detent is engaged, the lever is then forced toward the applicator body to foreshorten the lost motion linkage and thereby compress the spring. By releasing the detent, the force-applying mechanism is driven toward mechanism. This results in an unwieldy and somewhat bulky applicator. Furthermore, toggle linkage arrangements are subject to wear at a number of pivot points. Secondly, a major disadvantage of such an arrangement is the fact that if the handle is released prior to releasing the locking detent, the handle will spring back against the bias of the spring and may injure the user.

As was previously indicated, the force-applying member of an ampoule applicator may be retracted to a locked position by axially withdrawing a projecting end portion of the force-applying member. Such an arrangement is shown in U. S. Pat. Nos. 2,704,072 and 2,322,245 (FIGS. 12 and 13). Since these devices require a straight pull on the spring without any mechanical advantage, it is difficult to compress relatively strong springs. Furthermore, when the force-applying member is released (either accidentally while the force-applying member is being retracted, or deliberately by triggering the device), there exists the danger of pinching ones hand between the end of the applicator and the force-applying member.

SUMMARY OF THE INVENTION According to this invention, an ampoule applicator is provided which alleviates the foregoing prior art problems by providing an improved cocking mechanism and an improved locking device which serves as a one-way check means or full stroke compelling mechanism for the force-transmitting member. It should be appreciated, however, that this invention may be employed in devices other than ampoule applicators. For example, this invention may be employed as a full stroke compelling mechanism for a hand-operated crimping tool for electrical terminals and connectors to ensure a proper crimp prior to release of the jaws. Furthermore, the invention may be employed in lever-operated air guns to prevent the lever from springing back on the users hands prior to full cocking of the gun. 7

According to this invention, an ampoule applicator includes an elongated, cylindrical hollow body having one end adapted to removably receive an ampoule. The ampoule may be of the type which is adapted to inject a medicament into a patient by applying force to one end -of the ampoule. The applicator also includes a force-transmitting member or piston having a rod portion directed toward the ampoule, a head portion which is biased toward the ampoule by a relatively strong spring, and a lockable and releasable cocking mechanism for retracting the piston against the bias of the spring. As presently preferred, the cocking mechanism comprises a flexible cable having one end fixed to the head portion of the piston and its other end fixed to the periphery of a pulley which is mounted at the other end of the hollow, cylindrical body. The forceapplying member may be retracted against the bias of the spring by a lever or handle which, in this instance, rotates the pulley to thereby wind the flexible cable about the periphery of the pulley.

During retraction of the force-transmitting member, the tendency of the force-transmitting member to be driven toward the ampoule by the spring is resisted by a one-way check means or full stroke compelling mechanism. The one-way check means includes a rollable member, such as a sphere, which is positioned between the piston rod and the cylindrical housing. A wedge means is provided which causes the rollable member to be forced into firm frictional engagement with the piston rod and thereby restrain any tendency of the rod to move toward the ampoule. According to one aspect of this invention, the wedge means comprises a tapered slot in the cylindrical housing having sidewalls which coverge toward an imaginary apex which is directed toward the ampoule so that as the rollable member is rolled along the slot by movement of the rod toward the ampoule, it is progressively forced radially inwardly toward the rod by movement of the rod toward the ampoule, with a wedging effect that opposes such movement of the rod.

With the force-applying member in a retracted position and with an ampoule properly installed in the applicator, the force-applying member may be triggered or released by moving the rollable member out of its firm frictional engagement with the rod. According to the specific embodiment illustrated herein, this is accomplished by a pin mounted on the lever or handle which may be extended into the tapered slot to drive the rotatable member away from the imaginary apex of the tapered slot. To prevent repeated firing of the applicator (which would tend to cause fatigue to certain elements thereof) when an ampoule is not positioned in the applicator, a blocking device is provided which prevents entry of the pin into the slot unless the blocking means is contacted by an ampoule.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a cross sectional view of the applicator according to this invention showing the applicator in a tired condition.

FIG. 2 is an elevational view of the applicator, with portions broken away for clarity, showing the applicator in a cocked condition, with the lever not yet returned to a positioned adjacent the body of the applicator.

FIG. 3 is a fragmentary view of the applicator illustrating the tapered slot.

FIG. 4 is an end view of the applicator with portions broken away for clarity.

' FIG. 5 is a partially schematic view, illustrating the travel of the rollable member along the tapered slot.

DETAILED DESCRIPTION OF THE INVENTION There is disclosed in the drawing an ampoule applicator which, in combination with a hypodermic ampoule 11, is adapted to inject a medicament into a patient. The particular hypodermic ampoule l l illustrated herein is more fully described in the copending application of Hurschman et al., Ser. No. 1 14,493, filed Feb. 11, 1971, now U.S. Pat. No. 3,735,761, and assigned to the same assignee as the present application. The ampoule 11 comprises acylinder 12 which is preferably made from glass tubing.

One end of thecylinder 12 is closed by adiaphragm 14 which is pressed against it by aplastic clip 15. This closure arrangement is more fully described in the copending application of l-Iurschman et al. The other end of thecylinder 12 is closed by a plunger formed to have a sliding interference fit with the inner sidewall of thecylinder 12. Theplunger 20, thediaphragm 14, and

5 thecylinder 12, together, define achamber 21 which is substantially filled with a liquid medicament.

Entirely enclosed within thechamber 21 is ahypodermic needle 22. Thehypodermic needle 22 has a circular base (not shown) at the butt end of the needle that is mounted on theplunger 20 so that the needle is in substantial axial alignment with thecylinder 12 so that the pointed end of the needle is in position to be forced through thediaphragm 14.

Theampoule applicator 10 includes a cylindrical housing having anaxial bore 31 and acounterbore 32 therein. In order to mount the hypodermic ampoule I 11 in theapplicator 10, a mountingsleeve 33 is provided. The mountingsleeve 33 is threaded into one end of the applicator l0 and has an annular, axially extending, inwardly offsetshoulder 35 at one end thereof. The ampoule 1 1 is installed in the mountingsleeve 33 by inserting it through anopening 36 in thesleeve 33 and is held within the sleeve by a bayonet-type connection between the ampoule 11 and the sleeve. This connection is more fully set forth in the copending application of I-Iurschman, Ser. No. 114,423, filed Feb. 11, 1971, now U.S. Pat. No. 3,729,003. With the ampoule l1 properly installed in this manner, the opposite end of theampoule cylinder 12 projects a predetermined distance beyond theshoulder 35.

Theampoule applicator 10 also includes a forceapplying mechanism for driving theampoule plunger 20 from the position illustrated in FIG. 2 to the position illustrated in FIG. 1. The force-applying mechanism comprises a force-applying member or piston having ahead portion 46 which is slidably mounted within thecounterbore 32 and apiston rod 47 which axially projects toward theampoule plunger 20. Thepiston 45 is biased downwardly as viewed in the drawing by a relativelystrong compression spring 48.

Thepiston 45 may be retracted from the fired position illustrated in FIG. 1 to the cocked position illustrated in FIG. 2 by grasping ahandle 49 and swinging thehandle 49 away from thebody 30 to the position illustrated in FIG. 2. Thehandle 49 is pivotally connected at its upper end to apin 50 which extends transversely with respect to thebore 31. The upper end of thehandle 49 is bifurcated to provide a pair of spaced

flanges

51 and 52. Rotatably mounted on thepin 50 is apulley 53 which has acircumferential groove 54 formed in its periphery. Thegroove 54 has a flattenedportion 55 and across pin 56 extends across the flattened portion. As may be seen most clearly in FIG. 4, thepin 56 projects outwardly beyond the pulley faces. One end ofaflexible cable 57 is fixed to thepin 56, and the other end of the cable is fixed to thepiston head 46 by apin 58 extending across ashallow groove 59 cut into the piston head.

Thepiston 45 is raised to a retracted position by swinging thehandle 49 outwardly relative to thebody 30. As thehandle 49 is swung outwardly,

abutment portions

60 and 61 on the

flanges

51 and 52 bear against the extensions of thepin 56 to rotate thepulley 53 in a counterclockwise direction, as viewed in FIGS. 1 and 2, so that theflexible cable 57 is progressively wrapped about thepulley groove 54. As thecable 57 which prevents movement of the piston toward its fired or extended position until the check means is released. In the illustrated embodiment, the check means includes a rollable member orball 62. Theball 62 is assembled in thebore 32 by inserting it through asemicircular opening 63 in thebody 30. The diameter of theopening 63 is slightly greater than the diameter of theball 62 to permit this insertion step. Thesemicircular opening 63 blends into

straight coverging walls

64 and 65, which form a tapered or V-shaped slot. As may be seen in FIG. 5, as theball 62 travels from theopening 63 along the inside edges of the converging

slot walls

64 and 65, the center of the ball traces an imaginary line L, which approximates a hyperbolic curve and which curves toward thepiston rod 47. To ensure frictional contact at all times between theball 62 and therod 47, and between theball 62 and the inside edges of the

surfaces

64 and 65, a relativelylight compression spring 70 is provided which tends lightly to urge the ball toward an imaginary apexa of the tapered slot.

Thus, as thepiston rod 47 is retracted in the previously described manner, thepiston rod 47 moves theball 62 toward theopening 63 just enough so that relatively light pressure is exerted on thepiston rod 47 by theball 62. If, .during retraction of therod 47, thehandle 49 is released, therod 47 is urged toward the ampoule plunger by thespring 48. Any noticeable return movement of therod 70 in this direction, however, is resisted by the ball, since therod 47 will tend to rotate theball 62 toward the apex of the V-shaped notch, thus driving the ball into firmer frictional contact with therod 47 as theball 62 rides inwardly on the inside edges of the notch faces 64 and 65. It will be readily seen that this action rapidly builds up the pressure of the ball against therod 47 and edges of the

walls

64 and 65, and builds up the friction therebetween at a corresponding rate. As a result, only a minute movement of thepiston 45 causes a wedging of the ball between thepiston rod 47 and

walls

64 and 65 that stops further rolling of the ball in that direction while increasing the friction between the ball and the piston rod so that return movement of the piston is almost instantly arrested.

In order to ensure that theball 62 will effectively restrain therod 47 against forward movement toward the ampoule during retraction, the ball diameter, the angle included by the convergingsidewalls 64 and 6S, and the distance between therod 47 and thebody 30 are selected so that a preselected effective wedging angle obtains. It is known that a ball will restrain movement in one direction between relatively movable members if one of the members is provided with a wedge which slopes toward the other member at a preselected angle which exceeds the coefficient of sliding friction between the ball and the movable members. This principle is employed in overrunning clutches. For a steel ball in contact with steel members, the preselected angle should be between about 5 and 12, and preferably should be 7%". If the angle is less than 5, the frictional contact will be too great and it may be difficult to release the ball from frictional contact. If, on the other hand, the angle exceeds 12, the wedging action will not be firm enough and slippage may occur.

According to the present invention, it has been found that a ball rolling in a slot having converging sidewalls produces a wedging effect which corresponds to the wedging effect which results from the use of an actual wedge and which, itself, has an effective wedging angle. It is, of course, far simpler to merely stamp or cut a slot in a member than it is to weld or otherwise affix a separate wedge to one of the members. As used in the specification and claims of this application, the term effective wedging angle" is hereby defined as the slope of the locus of points traced by the center of a sphere rolling along a slot formed in a surface and having converging sidewalls, with the slope measured at the intersection of the locus and a plane defined by three points of contact by the sphere with the sidewalls of the slot and a member spaced from the slot (e.;g., the rod 47). The effective wedging angle is between about 5 and 12, and is preferably '7 H.

In FIG. 5, the line L represents the locus and theball 62 is shown to be locked in a position producing an effective wedging angle of 756, with the intersection of the curve L (the locus) and the aforementioned plane P being indicated by the reference numeral 95. It has been found that if the inside diameter of thehousing 30 is 0.650 inch, if the diameter of therod 47 is 0.300 inch, if the diameter of the 'ball 62 is 0.218 inch, and if the angle included by the

sidewalls

64 and 65 is about 28, an effective wedging angle will obtain.

A particular advantage of the slot and ball arrangement is that as the

sidewalls

64 and 65 wear after repeated use, the ball will tend to operate in a position closer to the convergence of the

walls

64 and 65 and, therefore, the effective wedging angle will be less than 7%. Therefore, the wedging effect: will increase during use of the device.

Although the spring biases theball 62 away from theopening 63, and ensures that the ball will not accidentally drop out of theopening 63, a further means is provided to ensure that the ball will remain in the applicator and to prevent tampering with the ball. To this end, there is provided asleeve 71 which extends from thesleeve 33 to a location which ensures that theopening 63 will be covered. For a purpose which will hereinafter become apparent, a portion of the slot is left uncovered by anaperture 72 in thesleeve 71.

The fully retracted position of thepiston 45 is illustrated in FIG. 2 and is established when thehandle 49 engages astop portion 73 of thebody 30. After thepiston 45 is retracted in this manner, thehandle 49 may be returned to the position illustrated in FIG. 1, and thepiston 45 will be held in its retracted position by the ball wedging action of the one-way check means. An ampoule. 11 may then be installed! in the applicator in the previously described manner.

For firing thepiston 45, means. are provided to release the one-way check means and render it inoperative during the piston stroke. To this end, there is provided apin 74 in thehandle 49. Thepin 74 is slidably mounted in anaperture 75 and has a head portion which bears against a slopedcamming surface 76 of atrigger piston 77. Thetrigger button 77 is slidable within aslot 78 in thehandle 49 and is biased to the position illustrated in FIG. 1 by aspring 79. By pushing thebutton 77 downwardly along theslot 78 and against the bias of thespring 79, thecam surface 76 forces thepin 74 axially through theopening 75 toward the body so that thepin 74 enters thebody 30 throughparallel extensions 80 of the

slot walls

64 and 65. As thepin 74 enters between theextensions 80, arounded end portion 81 of the pin engages anedge 82 of awasher 83 which is loosely mounted within thebore 32 and surrounds thepiston rod 47. Thewasher 83 is thereby driven upwardly, as viewed in FIG. 1, so as to drive theball 62 upwardly and away from the imaginary apex at of the tapered slot and out of firm frictional engagement with therod 47. When theball 62 has been moved in this manner, thespring 48 drives thepiston 45 downwardly to drive theplunger 20 to the position illustrated in FIG. 1 and thereby actuate the ampoule 11 to perform an injection.

Of course, it should be appreciated that thepin 74 could be located so that it would directly engage theball 62 and thewasher 83 could be eliminated. However, thewasher 83 performs a second function of preventing release of theball 62 by thepin 74 unless an ampoule is properly installed within the applicator. As

may be seen in FIG. 1, insertion of an ampoule into the applicator lifts thewasher 83 away from the shoulder as required to permit the pin to engage thelower edge 82 of the washer. If thewasher 83 is not lifted by the ampoule, it rests on theshoulder 35 in the position shown in dotted outline in FIG. 1 to effectively block entry of thepin 74 into theextension 80. So that thewasher 83 will perform its blocking function when the applicator is held in any position, alight spring 90 is provided which urges thewasher 83 toward theshoulder 35.

The invention is not restricted to the slavish imitation of each and every one of the details described above, which have been set forth merely by way of example with the intent of most clearly setting forth the teaching of the invention. Obviously, devices may be provided which change, eliminate, or add certain specific details without departing from the invention.

We claim:

1. An ampoule applicator comprising a body and means for mounting thereon a medicament-containing hypodermic ampoule adapted to inject a volume of medicament into a patient, said applicator also including force-applying means mounted on said body for forward movement toward said ampoule mounting means along a predetermined path from a fully retracted position, means biasing said force-applying means forwardly along said path, means for reversely moving said force-applying means to its fully retracted position against the bias of said biasing means, and one-way check means permitting reverse movement of said force-applying means toward its retracted position but preventing any substantial forward movement of said force-applying means toward said ampoule mounting means when said force-applying means is in its fully retracted position and when said force-applying means is in any position forward thereof, said one-way check means comprising a rollable member and wedge means normally urging said rollable member into firm frictional contact with said force-applying means to restrain forward movement thereof but permitting reverse movement thereof toward its retracted position, said check means being releasable to permit said forward movement, said wedge means comprising means defining a tapered slot in said body, said slot having sidewalls converging toward said ampoule mounting means.

2. An ampoule applicator according to claim 1, wherein said rollable member is spherical and normally positioned to roll along said tapered slot.

3. An ampoule applicator according to claim 2, including means biasing said rollable member toward the ampoule mounting means.

4. An ampoule applicator according to claim 1, including means to relieve firm frictional contact of said rollable member with said force-applying means for permitting said forward movement of said forceapplying means.

5. An ampoule applicator according to claim 1, I

wherein the sidewalls of said tapered slot converge at an included angle to produce an effective wedging angle of between about 5 and 12.

6. An ampoule applicator according to claim 1, wherein the sidewalls of said tapered slot converge at an included angle of about 28.

7. An ampoule applicator according to claim 1, wherein said means for moving said force-applying means to its retracted position against the bias of said spring means includes pulley means mounted on said body and flexible cable means having one end fixed to said force-applying means, and an opposite end fixed to said pulley means, and means to rotate said pulley means so that portions of said cable means are wrapped about said pulley means for pulling said force-applying means toward its retracted position.

8. An ampoule applicator according toclaim 7, wherein said pulley means is rotatably mounted on said body, and wherein said means to rotate said pulley means comprises a lever pivotally mounted on said body for swinging movement from a first position to a second position relative to said body, said pulley and lever having abutment means engaged by swinging said lever toward its second position for rotating said pulley and disengaged by reverse swinging of said handle toward its first position while forward movement of said force-applying means is restrained by said one-way check means.

9. An ampoule applicator comprising a body and means for mounting thereon a medicament-containing hypodermic ampoule having medicament-injecting means adapted to inject a volume of medicament into a patient, said applicator also including force-applying means mounted on said body for movement toward said ampoule from a retracted position relative to said body for actuating said ampoule, means biasing said force-applying means toward said ampoule, means for moving said force-applying means to its retracted position against the bias of said biasing means, said means for moving said force-applying means including pulley means mounted on said body, flexible cable means having one end fixed to said force-applying means and its opposite end fixed to said pulley means, means to rotate said pulley means so that portions of said cable means are wrapped about said pulley means to pull said force-applying means toward its retracted position and one-way check means, said one-way check means comprising a rollable member and wedge means normally urging said rollable member into firm frictional contact with said force-applying means to restrain forward movement thereof but permitting reverse movement thereof toward its retracted position, said check means being releasable to permit said forward movement, said wedge means comprising means defining a tapered slot in said body, said slot having sidewalls converging toward said ampoule mounting means.

10. An ampoule applicator according to claim 9, wherein said rollable member is spherical and normally positioned to roll along said tapered slot.

11. An ampoule applicator according toclaim 10, including means biasing said rollable member toward the ampoule mounting means.

12. An ampoule applicator according to claim 9, including means to relieve firm frictional contact of said rollable member with said force-applying means for permitting said forward movement of said forceapplying means.

13. An ampoule applicator according toclaim 10, wherein the sidewalls of said tapered slot converge at an included angle to produce an effective wedging angle of between about and 12.

14. An ampoule applicator according toclaim 10, wherein the sidewalls of said tapered slot converge at an included angle of about 28.

15. An ampoule applicator according to claim 9, wherein said pulley means is rotatably mounted on said body, and wherein said means to rotate said pulley means comprises a lever pivotally mounted on said body for swinging movement from a first position to a second position relative to said body, said pulley and lever having abutment means engaged by swinging said lever toward its second position for rotating said pulley and disengaged by reverse swinging of said handle toward its first position while forward movement of said force-applying means is restrained by said one-way check means.

16. An ampoule applicator according toclaim 12, wherein said pulley means is rotatably mounted on one end of said body, wherein said means to rotate said pulley means comprises a lever pivotally mounted on said body for swinging movement from a first position to a second position relative to said body, said pulley and lever having abutment means engaged by swinging said lever toward its second position for rotating said pulley and disengaged by revese swinging of said handle toward its first position while forward movement of said force-applying means is restrained by said one-way check means, and wherein said means to remove aid rollable member from its frictional contact with said force-applying means comprises pin means on said lever which is operable to move said rollable member out of firm frictional contact with said force-applying means when said lever is in its first position.

17. An ampoule applicator according to claim 16, including means operable when an ampoule is not installed in said applicator to block said pin means and prevent movement of said rollable member out of firm frictional contact with said force-applying member.

19. An ampoule applicator according to claim 18, including means operable when an ampoule is not installed in said applicator to block said pin means and prevent movement of said rollable member out of firm frictional contact with said force-applying member.

Claims

1. An ampoule applicator comprising a body and means for mounting thereon a medicament-containing hypodermic ampoule adapted to inject a volume of medicament into a patient, said applicator also including force-applying means mounted on said body for forward movement toward said ampoule mounting means along a predetermined path from a fully retracted position, means biasing said force-applying means forwardly along said path, means for reversely moving said force-applying means to its fully retracted position against the bias of said biasing means, and one-way check means permitting reverse movement of said forceapplying means toward its retracted position but preventing any substantial forward movement of said force-applying means toward said ampoule mounting means when said force-applying means is in its fully retracted position and when said force-applying means is in any position forward thereof, said one-way check means comprising a rollable member and wedge means normally urging said rollable member into firm frictional contact with said forceapplying means to restrain forward movement thereof but permitting reverse movement thereof toward its retracted position, said check means being releasable to permit said forward movement, said wedge means comprising means defining a tapered slot in said body, said slot having sidewalls converging toward said ampoule mounting means.

4. An ampoule applicator according to claim 1, including means to relieve firm frictional contact of said rollable member with said force-applying means for permitting said forward movement of said force-applying means.

5. An ampoule applicator according to claim 1, wherein the sidewalls of said tapered slot converge at an included angle to produce an effective wedging angle of between about 5* and 12*.

6. An ampoule applicator according to claim 1, wherein the sidewalls of said tapered slot converge at an included angle of about 28*.

8. An ampoule applicator according to claim 7, wherein said pulley means is rotatably mounted on said body, and wherein said means to rotate said pulley means comprises a lever pivotally mounted on said body for swinging movement from a first position to a second position relative to said body, said pulley and lever having abutment means engaged by swinging said lever toward its second position for rotating said pulley and disengaged by reverse swinging of said handle toward its first position while forward movement of said force-applying means is restrained by said one-way check means.

11. An ampoule applicator according to claim 10, including means biasing said rollable member toward the ampoule mounting means.

12. An ampoule applicator according to claim 9, including means to relieve firm frictional contact of said rollable member with said force-applying means for permitting said forward movement of said force-applying means.

13. An ampoule applicator according to claim 10, wherein the sidewalls of said tapered slot converge at an included angle to produce an effective wedging angle of between about 5* and 12*.

14. An ampoule applicator according to claim 10, wherein the sidewalls of said tapered slot converge at an included angle of about 28*.

16. An ampoule applicator according to claim 12, wherein said pulley means is rotatably mounted on one end of said body, wherein said means to rotate said pulley means comprises a lever pivotally mounted on said body for swinging movement from a first position to a second position relative to said body, said pulley and lever having abutment means engaged by swinging said lever toward its second position for rotating said pulley and disengaged by revese swinging of said handle toward its first position while forward movement of said force-applying means is restrained by said one-way check means, and wherein said means to remove aid rollable member from its frictional contact with said force-applying means comprises pin means on said lever which is operable to move said rollable member out of firm frictional contact with said force-applying means when said lever is in its first position.