OPERATING FLUID APPLICATOR MANUALLY, CONTROLLED ACTIONCROSS REFERENCE WITH A RELATIVE APPLICATION This application is a continuing part of the copending application of United States Patent Series No. 08 / 838,078 by Gordon Howard EPSTEIN et al. Filed on April 15, 1997 and entitled "APPLICATOR FOR AMOUNT AMOUNTS. MEASURES WITH USE OF CONTROLLED SUCTION ", (referred to as" mother "or" mother application "in the present), International application PCT / US98 / 07488, and International application PCT / US98 / 07846 whose descriptions are hereby incorporated herein by reference to them.
BACKGROUND OF THE INVENTION This invention relates to a manually operable, controlled-action fluid applicator of the type in which a user, while holding the applicator in one hand, operates a fluid jet actuator to drive fluid from a reservoir and out of the applicator, through an applicator tip. Such applicators have many different uses and are well suited particularly for dispensing glues and adhesives and are in fact common household articles for applying epoxy adhesives, glues and viscous caulks for carpentry and so on. More specialized uses with higher behavioral requirements, as will be described herein, are to apply tissue adhesives in a surgical context to repair tissue damage, and for professional, medical, veterinary or biological equivalent uses. The fluid applicators described above provide better control over the fluid emerging from the applicator than is possible by simply squeezing a deformable glue tube to expel the glue from a nozzle attached to the tube. However, the control that can be achieved with known applicators is insufficiently accurate for many applications. In particular, in surgical applications, there is a need for a fluid dispenser for dispensing tissue adhesive which can be controlled in a precise and predictable manner by the user to supply and apply small amounts of adhesive at target locations. In addition, there is a need for an applicator that can be fastened in a number of ergonomically different desirable configurations. There are a number of teachings in the literature of specialized applicator constructions that include those of the present inventor, which have been designed to meet the particular needs of the adhesive application in fabrics, but none is completely satisfactory due to deficiencies in the mechanism of impulsion which converts the manual force applied to the actuator in movement of the fluid outside the applicator. In an optional major construction, multiple fluids that are maintained in multiple reservoirs can be dispensed with or without mixing within the applicator. Common homemade epoxy glue applicators supply parallel streams of resin and hardener for external mixing and teach that mixing inside the applicator, or on its external surfaces, should be avoided to prevent sticking and blocking of its fluid passages. In contrast, a tissue adhesive applicator, such as for example that described in U.S. Patent Nos. 5,226,877 and 5,405,607, has deposits for two fluids, for example a phase containing fibrinogen and a phase containing thrombin, a mixing chamber and a simple outlet for mixed fluids. In the described applicators, the manual effort provides the necessary driving force and typically, but not necessarily, the applicator has a barrel that can be held comfortably while leaving the thumb free to operate the jet actuator which is conveniently positioned for the purpose. An extended applicator tip, which can have a variety of conformations, allows users with expertise to apply the assorted fluid to a target location with considerable precision. Preferably, the applicator is neutral for both hands, being equally manageable for operation with the left hand or with the right hand. A well-known construction of fluid applicator comprises a barrel body which is intended to be held in the user's hand, which body incorporates a fluid reservoir, and a trigger actuator, to supply returnable spring fluid, manually applied pressure on the which pushes fluid out of the reservoir through a tip of the applicator. The drive comprises a toothed rack extending over the length of the tank to be unloaded, a plunger and a driving pawl, the plunger and the driving pawl being coupled with the trigger actuator via pivoting means so that the operation of the actuator causes the drive pawl to engage with the teeth of the rack, to pivot and index the piston to the reservoir. In the return path the driving pawl returns on the rack while the engagement of a second locking pawl with the toothed rack prevents recoil. Such applicators are commonly available in hardware stores and are standard articles for dispensing and applying construction adhesives, caulking and the like. Generally, they provide an increased mechanical advantage as the trigger is tightened, making the controlled fluid application stably difficult to reach. For this and other reasons, such hardware applicators are not suitable for medical and surgical uses. In addition, such glue or caulking applicators accommodate only a single fluid and are designed for two-handed operation. Laghi, U.S. Patent No. 5,328,459, mentions the need to generate high pressures to produce low flow regimes when thixotropic or non-Newtonian fluids are supplied. Laghi employs small electric motors, preferably stepper motors, to provide high torque when boosting a dispenser whose expensive and cumbersome remedy does not solve the problems faced by surgeons who wish to apply one or more medically useful fluids to patients during surgery. There is also a need for such an applicator that can be held and operated with one hand and which accommodates and supplies multiple fluid components, for example, two components of a fibrinogen adhesive. Rowe et al., U.S. Patent No. 5,612,050, discloses an applicator that employs a trigger-operated compression spring to provide a driving force to deliver polymeric fluids to a location in the tissue of a patient. The trigger 182 includes a cam surface 180 which increases the mechanical advantage in a compression connection 158 as the trigger grip progresses providing the user with an unbalanced response, making it difficult to adequately control the fluid discharge. There is, therefore, a need for a manually operable fluid applicator that has a controlled action that suited it for precision applications such as, for example, dispensing and applying medically useful fluids during surgery.
BRIEF DESCRIPTION OF THE INVENTION The invention, as claimed, is intended to provide a remedy. Solves the problem of providing a manually operable fluid applicator with a precisely controllable action to supply small amounts of fluids. Accordingly, the invention provides a manually operated fluid applicator having: a) a fluid container for containing fluid; b) a movable actuator operable in a repetitive manner, with a stroke of the actuator effected by a force applied manually on the movable actuator, for supplying fluid from the applicator by fluid displacement from the fluid container, the stroke of the actuator having a start phase and a termination phase; and c) a drive mechanism for transferring the force applied manually on the movable actuator to a force that displaces fluid exerted on the fluid in the fluid container; wherein the mechanical advantage of the drive mechanism with respect to the ratio of the fluid displacing force to the manually applied force is larger in the initial phase and smaller in the entire termination phase. Providing a relatively greater mechanical advantage in the start phase of the actuator stroke, the initial friction resistance and inertia can be easily overcome, while a smaller mechanical advantage during the termination phase allows the user to precisely control the amount of fluid assorted and avoid unnoticed excesses. Preferably, the mechanical relationships in the start and end phases respectively are such as to overcome the resistance of the initial friction and provide a smooth touch of the actuator throughout the stroke. In a preferred embodiment, the actuator may comprise a manually operable and engagable actuator member, an impeller member and a pivoted connection having one end pivoted to the impeller member and having another end, the applicator further comprising a connection The impeller between the actuating member that can be depressed and the other end of the pivoted connection connects the driving connection providing freedom of movement of the other end of the connection pivoted in one direction to reduce the proportion of driving force transmitted as the stroke progresses. Also in a preferred embodiment, the applicator is a plural fluid applicator having a plurality of fluid containers respectively for a plurality of fluids and wherein the drive mechanism acts on the fluids in the fluid containers in equipment to exert a force of fluid displacement on each fluid simultaneously.
BRIEF DESCRIPTION OF THE DRAWINGS Some illustrative embodiments of the invention, and the best mode contemplated for carrying out the invention, are described in detail below with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a medical fluid applicator mode employing an actuator mechanism according to the invention; Figure 2 is a plan view of another embodiment of a medical fluid applicator having close external similarity to the embodiment of Figure 1; Figure 3 is a sectional view on line 3-3 of the applicator shown in Figure 2; Figure 4 is an end view in elevation to the left, or rear of the applicator shown in Figures 2 and 3; Figure 5 is an end view in elevation to the right, or front of the applicator shown in Figures 2 and 3; Figure 6 is an enlarged view of a portion of Figure 3, showing an actuator button as a trigger in a rest position; Figure 7 is a view similar to Figure 6, showing the actuator button as fully depressed trigger; Figure 8 is a perspective view of the actuator button as a trigger; Figure 9 is a perspective view of an anchor link, being a component of a drive mechanism for the applicator; Figure 10 is a perspective view of a trigger link, another component of the applicator driving mechanism; Figure 1 1 is a perspective view of a ratchet being one component of the drive mechanism of the applicator; Figure 1A is an end elevation of the ratchet of theFigure 11, looking in the backward direction; Figure 12 is a perspective view of a toothed rack being still one component of the drive mechanism of the applicator; Figure 13 is a partial side elevational view of the ratchet of Figure 1 1 coupling with the rack of Figure 12; Figure 14 is a side elevational view of a hinged access cover being a component for the applicator shown in Figures 2-5; Figure 14A is an end elevation view of the cover shown in Figure 14, viewed from a front end of the applicator, the right end being as seen in Figure 14; Figure 14B is a plan view of an alternate hinged access cover; Figure 14C is a section on line 14C-14C of Figure 14B;Figure 14D is a perspective view of a spring pin component of the cover shown in Figures 14B and 14C; Figure 15 is a perspective view of a double syringe that is still a component of the applicator drive mechanism; Figure 16 is a perspective view of a syringe barrel comprising two fluid reservoirs, still being one component of the applicator of the invention;DETAILED DESCRIPTION OF THE PREFERAL MODALITIES Figure 1 gives a good overall impression of the exterior, three-dimensional configuration of a preferred embodiment of medical fluid applicator, embodying the invention, such an applicator is particularly suitable for the application of tissue adhesive during human or veterinary surgery. Referring to Figure 1, the medical fluid applicator shown is a device for manual fastening which has a tipapplicator for the purpose of being run across a surface11 of tissue to discharge one or more fluids under the control of an operator, who may either be a surgeon or a physician. The applicator tip 10 comprises a suction tube 12, coupled to a vacuum source (not shown), and a fluid spout tube 14, which communicates with one or more sources of medical fluids within the applicator. Although the term "fluid" as used in physics may comprise any matter in the liquid or gaseous state, the applicators described herein, in addition to their described vacuum functions, are not specifically intended to supply gases. Accordingly, the use of the term "fluid" herein is intended to encompass non-gaseous, flowable materials, which can be usefully supplied from the described applicators, including liquids, dispersions, pastes in gels and the like, being suspensions of solid particles in a liquid phase, thixotropic and semi-solid materials. Those skilled in the art will understand that more viscous fluids may require relatively large passages and holes, while less viscous fluids may require better seals to prevent leaks. The purpose of Figure 1 is to suggest a possible general external appearance of a preferred embodiment of applicator according to the invention, and its use. The more detailed embodiment shown in Figures 2-5 has small differences in external appearance of the embodiment of Figure 1, such differences can be seen when the drawings are read carefully along with the description herein.
As will be described in greater detail hereinafter, the preferred embodiments of the disclosed applicator are suitable, inter alia, for surgical or even microsurgical applications, where millimetric precision control of each step of the procedure is essential, and allows the surgeon or another user dispensing and applying one or more medically useful fluids from tip 10 of the applicator to tissue surfaces, in a controllable, aesthetic process that can be augmented by the controlled application of suction. The particular embodiment illustrated also provides premixing of two fluids contained in separate reservoirs before discharging them through the spout tube 14 and for applying suction to clean waste products of reaction from the spout tube 14. Other modalities could supply a single fluid without premixing, premixing three or more fluids, or supplying multiple fluids of multiple deposits, without premixing, if desired, as will be apparent to those skilled in the art in light of this disclosure. The applicator has a barrel body housing 16, which extends longitudinally ending in a front tip housing 18 from which the applicator tip 10 hangs down. The applicator can be received comfortably in a user's hand, either in the palm, or between the thumb, middle and index fingers, as a large-sized pen, where it will be held usually with the tip housing 18 projecting out in front of the user, as an extension of the user's hand. Addresses such as "forward" and "backward", are used herein in this sense to be, respectively, away from, or close to, a point of origin or attachment, the tip housing 18 being forward while the body housing 16 is rearward. Other directions assume, merely for reference purposes, that the user holds the applicator with the body housing 16 which extends approximately horizontally. The elastically resilient latches 19 allow the nose housing 18 to be removed to allow for reloading of the applicator with fluids and to allow attachment of a different tip housing 18 that provides different functionality, for example as described in the parent Application No. Series 08 / 838,078. Exactly behind the tip housing 18, a tubular housing extension also depends downwardly to provide a suction hole 20 which contains within it a suction connector (to be described). The suction orifice 20 also serves as a guard or guide for the user's fingers, placing them, in the case of user surgeons, clean of patient tissues or fluids, and of any surgical instruments in the vicinity of the work area. Projecting upwards from the body housing 16 is a fluid jet actuator as a button, or trigger 22, conveniently positioned for operation by a thumb of the user. Exactly forward, or distally, of the trigger 22, an oppressive control valve button 24, which also projects upwardly from the body housing 16, operates a valve (to be described), within the body housing 16, to control the suction application. Both the trigger 22 and the button 24 of the control valve are spring-loaded to the raised positions shown. A hinged cover 26 covers a larger portion of the rear end of the applicator, providing access to the interior for recharging, maintenance, and disassembly, while the forward facing holes 28, positioned on either side of the applicator, allow the view of the reservoirs 30. of fluid (one visible in Figure 1) within the applicator to monitor the progress of filling operations and facilitate the removal of bubbles and the like. In use, the surgeon or other user, or operator, will normally run the applicator through a tissue or other surface to be treated, in the direction of the arrow 32, so that the vacuum of the suction tube 12 can prepare the surface for fluid application of the spout tube 14, extracting undesirable fluids 34 (or particulate solids) from the surface 1 1 of tissue, eg blood, other body fluids or excess adhesive. Medical fluids, v. g. , a fabric adhesive premixed in the applicator, can be dispensed at a rate controlled by the operator by oppressing the trigger 22, and applied to the tissue surface 1 1 as droplets, droplets or beads or as a linear application 36 or another pattern, as desired by the user, by appropriate manipulation of the applicator. The trigger 22 can be repeatedly depressed to supply fluid until the reservoirs 30 are completely depleted, as indicated by a distinctive audible tone emitted by the device, or indicated visually, by touch, or by other suitable means, the user can remove the tip housing 18 and refill the applicator, as described in the parent Application. The modality of the medical fluid applicator shown in Figures 2-5 has a somewhat different shaped body housing 16 and tip housing 18, but otherwise incorporates the aspects described in relation to the embodiment of Figure 1, as shown in FIG. indicates by using the same reference numerals. The aspects of the illustrated device that are relevant to the invention as claimed herein, and certain others, but not all aspects will be described here in detail. Other inventions, subject to one or more patent applications having inventors common with those of the present invention, are incorporated in the illustrated embodiment and their structure and operation that they incorporate may or may not be described in detail herein. Referring to Figures 2-5, the applicator shown comprises a valve housing 38 having a suction adapter 39, inside the suction hole 20, said suction adapter 39 can be connected to a suction source (not shown) for applying suction to the suction tube 12 employing the structure in the tip housing 18 which is not described here. The suction control valve actuated by the button 24 comprises a valve core, a valve launcher, and other valve elements, as shown in the drawings, or as will be otherwise apparent to those skilled in the art, and which they will not be described here in detail, but they enable the suction tube 12 to be connected to the suction adapter 39 and enable the spout tube 14 to selectively connect to the mixed output of two medical fluid reservoirs 30 (one of which is shown in FIG. Figure 3) or to the suction source to be cleaned of obstructions. The reservoirs 30, as shown in this embodiment, are cylindrical, tubular containers arranged in parallel, in side-by-side relationship, at the front end of the housing 16 of the body. A reservoir 30 is referenced in Figure 2. The other reservoir 30 rests along the shown one, behind the plane of the paper. The two fluids contained separately in the tanks 30, can be supplied to the front via separate fluid paths through the tip housing 18, to a mixing chamber and from there, as a mixture, to the spout tube 14. Again, this structure is not described in detail here. The reservoirs 30 can have a variety of shapes as long as they can contain the desired fluid, are pressurizable by a suitable driving mechanism, and are suitably coupled to supply the fluid contained forward. For example, each reservoir 30 may comprise a bulb, or flexible tube, which is directly compressed when coupled by an actuator member externally, for example a plunger or lever. A barrel 40 of integrally constructed syringe has a pair of plungers 42 (one shown in Figure 3) movable in tandem, slidably within the reservoirs 30, to pressurize and propel the fluid out of the reservoirs 30, in response to the pressure of the thumb or fingers of the user in the trigger 22. The plungers 42 are preferably in a narrow sliding fit in the reservoirs 30 to prevent leakage of fluid out of the reservoir 30, rearwardly beyond the plunger 42 for which purpose the plungers 42 can withstand elastic O-ring seals (not shown), if desired. Such a closed-fit plunger naturally offers significant frictional resistance to movement, especially when equipped with seals, and especially if the seals are dry at the beginning of the trip. Consequently, it is desirable for a manually energized drive mechanism, or equivalent, provide a high mechanical advantage at the beginning of the trip, to overcome this resistance. The piston drive mechanism shown in the drawings converts the user effort, applied to the trigger 22, into sliding movement of the pistons 42 in the reservoirs 30 and comprises, in sequence from the trigger 22 to the reservoirs 30, a link 44 of anchor, a trigger link 46, a driving member or ratchet 48, a toothed rack 50, and double plunger 40. The anchor link 44 is pivotally secured to one end of each side of the body housing 16 at points 70 of pivot (not shown), and at its other end is engaged by a hinge 52 comprising a pair of pivoting joints (only one is visible in Figure 3), at one end of the trigger link 46. The other end of the trigger link 46 is coupled to the pawl 48 by a pair of joints 54 (one shown) so that the anchor link 44 and trigger link 46 provide a compound lever that converts the pivoting drive of the trigger 22 into movement. forwardly in the direction of the length of the pawl 48. A return tension spring 55 extends between the anchor link 44 and the trigger link 46 by pushing them together and applying a push back to the trigger 22 through the coupling the hinge 52 with a platform 60 which extends on the underside of the trigger 22. The pawl 48 has a ratchet hook 56 which engages the toothed rack 50 and runs together with the pawl 48 in the forward direction of the Applicator The rack 50 has a downward stop engaging in a bag in the barrel 40 of the syringe (whose structure is to be described) whereby the barrel 40 of the syringe moves forward with the rack 50, plungers 42 driving along of the reservoirs 30 to force the stored fluid out of them to supply it from the spout tube 14. Referring further to Figure 8, the trigger 22 has an approximately triangular shape, in the plane of Figure 3, with external ribs 56, or roughened, for grip and feel, and is attached to the body housing 16 by a pin 58 of pivot at its rear end where the trigger has bearings 57 for receiving the pivot pin 58. The forward end of the trigger 22 oscillates about the pivot 58 as force is applied thereto, and is received downwardly in the body housing 16. The platform 60 is positioned intermediate the length of the spacer 22 and extends in a direction that is divergent forward from the general direction of the external surface 65 of the trigger 22. Reverse, the platform 60 ends in a stop 67 downwardly (Figure 3), against which the hinge 52 rests in the relaxed (raised) position of the trigger 22, in which position, the hinge 52 is approximately at the midpoint of the length of the trigger 22. Relevant surfaces of the platform 60, anchor link 44 and trigger link 46, are smooth, or polished, suitably, to reduce friction so that hinge 52 slides through platform 60. Notches 61 (one shown) on either side of trigger 22 constitute travel limiting stops, as will be described. The bearings 57 are formed with the adjacent stops 59 arising from the profile of the trigger 22 uniformly with the body housing 16 and the cover 26, facilitating the comfortable operation of the applicator. Referring to Figure 9, the anchor link 44 comprises a pair of separate arms 62, each terminating in a rounded hook 63 and which are interconnected by a reinforcing network 64. The arms 62 are mounted on an arrow 66 projecting outwardly on either side of the hooks 63 and are glued to either side of the body housing 16 at pivot points 70, so that the anchor link 44 can pivot, or oscillate around the pivot points 70 (one shown in Figure 3). The hooks 63 can hold a bar or the like so that the anchor link 44 can be mounted for pivotal movement around both ends of the arms 62. A depression 68 accommodates one end of the return spring 55 to be secured approximately on the shaft. of pivot defined by the pivot points 70. One end of the arrow 66 has a key 72 which is a movement stop that prevents excessive travel and possible agglutination of the drive mechanism. The anchor link 44 is dimensioned so that the arms 62 are received within the trigger 22, as shown in Figure 3, and the pivot points 70 are arranged in alignment with the notches 61 on the sides of the trigger 22 whereby the notches 61 engage with the arrow 66 to provide stops, defining the end of the trip down the trigger 22. Referring to Figure 10, the trigger link 46 is also designed to be pivotally mounted on each of its two ends and comprises a central field 74 with a pair of cubes 76 as bars projecting from the flanges 78 to one end and a pair of arms 80 widely spaced at the other end which each end in a rounded post 82. The hubs 76 engage with the hooks 63 of the anchor link 44 to form two pivoting joints comprising the hinge 52, while the post 82 engages the equalizing depression in the ratchet 48 (to be described) to form the joint 54. The spindle (not shown) within a central opening 84 in the field 74 provides a secure point for the other end of the return spring 55, said securing point being preferably positioned approximately midway between the hubs 76 and the posts 82. for additional leverage.
The anchor link 44 and trigger link 46 are thus, as stated above, coupled together on the hinge 52 to form a compound lever secured to the body housing 16 at the pivot points 70, said lever unfolds and moves the joint 54 with pawl 48 forward, as pressure is applied to hinge 52 by oppression of trigger 22. Referring to Figure 11, pawl 48 comprises an elongate finger 88 extending from a base 90 in the forward direction of the applicator and ending in a hook 92 of ratchet coupler ratchet. Any side of the base 90 are rocker arms 94 each of which has a top fulcrum pin 96 positioned above the finger 88, and a recess 98 that is downwardly dependent to receive the hub 76 of the trigger link 46, so that the joint 54 forms. Each hub 76 is for adjustment, fast in its respective cavity 98, for two-way load transmission. An elongated bar spring 100, elastically resisting opposing torsional forces applied to its ends in a plane passing through the spring, projects backward from each fulcrum pin 96 and is inclined downwardly toward the finger 88 (FIG. 13). ). A guide bar 102 runs below the finger 88, extending along its length, and slidably engageable with a slot in the toothed rack 50. Each bar spring 100 is accommodated for sliding movement on a horizontal rail 104 placed one on each side of the body housing 16 (Figure 3) and acts to rotate the ratchet finger 88 upwardly at the forward travel end of the pawl 48, lifting the ratchet hook 92 and uncoupling it from the rack 50. Referring to Figure 12, the zipper 50 has a longitudinally extended shape with a central slot 106 for receiving the guide bar 102, on either side of said central slot 106 are asymmetrical patterns of parallel rows of raised teeth 108 extending laterally with respect to the direction of travel of the zipper 50. As described, and claimed, in more detail in one or more other patent applications with inventor is common with the present application, the patterns of the teeth 108 interact with fixed ram patterns (not shown) to generate a sequence of audible indicator tones, as the rack 50 moves forward, said tone sequence audibly indicates the degree of depletion of deposits 30 to the user (and others in the vicinity). On either side and below the tooth patterns 108, there are side pieces 1 10 which support the rack 50 for sliding movement in the body housing 16 in grooves or depressions (not shown). The side pieces 1 10 end forward on cam surfaces 112 which engage with cavities 98 of the pawl 48 at the end of the travel of the rack 50 and lift the ratchet hook 92 out of engagement with the teeth 108. It is thus decoupled by the ratchet 48, the rack 50 is free to move in the body housing 16, after opening the hinged cover 26, allowing its removal from the body housing 16, to disassemble the applicator or, more importantly, to allow themanually removing the zipper 50, sliding it back into the grooves in the housing, to fill the reservoirs 30 with fluid, using an equalization filler device, for example as described in the parent and other related applications. Figure 13 shows, in profile, a possible shape of the ratchet hook 92 in the pawl 48, namely triangular, and a corresponding tooth profile 108 of the racking 50, each of which has a face 109 facing forward inclined and one face 111 backward perpendicular. The forward movement of the ratchet 48 or the backward movement of the rack 50 maintains the engagement of the ratchet hook 92 with the teeth 108 of the rack., transmitting any movement from one drive member to the other while the relative opposite movement causes uncoupling. At its rearward end, the zipper 50 carries a stop indicator bar 114, optionally marked with an indicator line 115, such indicator bar 114 is supported on a buttress 116 to transversely extend the rack 50. The structures of the indicator bar 114 and buttress 116 of support are relatively robust to provide a handle for manual removal of the toothed rack 50 of the body housing 16. Depending downstream of the rear end of the zipper 50 there is a block shaped key 120 which is received in a bag 122 in the double syringe 40 (Figure 15) and collects the barrel 40 of the syringe with the rack 50 for movement in two directions with it, longitudinally to the body housing 16. Such a coupling allows the reservoirs 30 to be filled by pulling the rack 50 back from an advanced position forward, holding the indicator bar 114, to draw new aliquots of fluid into the reservoirs 30, for example, as described in the parent Application 08 / 838,078. Referring to Figures 14-14A, and Figures 2-3, the cover 26 extends generally longitudinally on a backward portion of the applicator, just behind the reservoirs 30 and covering most of the extension of the zipper toothed 50 when it is in its most rearward position (with 30 tanks full). The cover 26 has a forward extension 117 which carries the hinge structure 121, mountable on the pivot pin 58 to provide the cover 26 with a hinge connection to the body housing 16 and whose extension terminates in a tongue 119 toward down arranged centrally (Figure 14A). A rear, horizontally extending tab 123, and side lips 125, adjacent the tab 123, provide convenient lifting means for opening the cover 26, which, if desired, can be snap-fit with the body housing 16 (which employs a structure not shown). Hanging from the front end of the cover 26 is an array of tone rams or emitter 127 engaging the teeth 108 as the rack 50 advances forward, emitting various tones, as described in one or more of the co-pending applications common authors. Referring further to Figure 13, the tone emitter 127 is structured and configured to be sufficiently deformable to travel on the inclined front face 109 of each rack tooth 108, yet stiff enough to act as a locking pawl, locking against the back side 1 1 1 of each tooth 108 of the rack and preventing backward movement of the rack 50, aiding in the prevention of return flow or return extraction. The tongue 1 19 is preferably elastic and configured to be engaged by the finger 88 of the ratchet 48 to urge the ratchet hook 92 downward to interdigitate with the teeth 108 of the rack, for which purpose, the upper surface, rearwardly, which is referred to by 93 in Figure 13, the finger 88 of the pawl is curved or beveled to promote the elastic deformation of the tongue 1 19 as it is engaged by the finger 88 of the pawl. The limit of the backward travel of the ratchet 48 is such that it does not obstruct the tone emitter 127. In the alternating construction of the cover 26 shown in Figures 14B-14D, where parts with similar functionality carry similar reference numerals although they may have a different configuration of their configurations in the embodiment shown in Figures 2-3 and 14-14A , the tongue 1 19 downwardly and the tone emitter 127 are incorporated in a one-piece elastic pin 131 which is press-fitted to the projections 131 at the front end of a plastic cover body 133 which is engaged by the openings 136. This construction provides additional design options that allow greater elasticity and durability to be built in the tongue 19 and the tone emitter 127 forming the pin 131 of a material other than the cover body 133, for example spring steel or the like. As shown, the tongue 1 19 is bent backward, best for engaging the ratchet finger 88 and pushing it down to interdigitate the ratchet hook 92 with the teeth 108 of the zipper, the tone emitter 127 as shown in Figure 14D it is configured as a single rectangular sound board, or resonance plate, which extends approximately across the width of the rack 50, and which has sufficient rigidity to generate audible sound vibrations when struck by one or more of the teeth 108 of the zipper. The volume and other acoustic characteristics of the generated sound can be varied by suitable variations in the shape, area, thickness, and other characteristics of the tone emitter 127, which can also be digitized, as shown in Figure 14A, in the construction pin integral of Figure 14D, if desired. As shown, the tone emitter 127 can, with this pin design, be at a sharp forward angle to positively lock against the teeth 108 of the rack, preventing backward movement of the rack 50 until the cover 26 is closed. opens. The hinged cover 26 is translucent or transparent and preferably carries a scale 1 18 against which the trip of the indicator bar 1 14 can be seen and measured (Figure 2). Since the pistons 42 are linearly coupled to the rack 50, as will be described, the travel of the indicator bar 14 seen against the scale 16 is indicative of the travel of the pistons 42 in the reservoirs 30 and this of the amounts of fluids assorted from the reservoirs 30. By opening the cover 26 the tone emitter 127 is oscillated out of engagement with the rack 50 and the tongue 1 19 out of engagement with the finger 88 of the pawl 48. Referring to FIG. 15, FIG. 122 pouch in the double syringe40 is formed in a base 124 from which the plungers 42 extend to have fluid engagement towards the ends 126 in the reservoirs 30, said ends 126 may carry peripheral seals, or O-rings, although such seals are not shown. The pistons 42 are molded with reinforcement slots 128. Referring to Figure 16, the barrel 40 of the syringe is formed in one piece with a core joining the two reservoirs 30 shown here as being cylindrical, a preferred configuration, and a circular section that is optional, but convenient. The reservoirs 30 end in nozzles 132 at their front ends through which the fluids in use can be unloaded or received during refilling. The rear ends of the reservoirs 30 have open holes 134 for receiving the plungers 42 for longitudinal travel in the reservoir. Preferably, the plungers 42 directly contact the fluid in the reservoirs 30 so that no additional transverse divider or barrier prevents the fluid from being drawn to one or both of the reservoirs 30 by retracting the plungers 42 back during refilling. However, in alternate constructions, for example, constructions employing disposable fluid cartridges, the cartridge will have a rear end wall that separates the plunger 42 from the fluid content of the cartridge, so that refilling by the removal of the plunger may not be appropriate. A wide variety of fluids can be accommodated in the reservoirs 30 for filling and application with the novel applicator described herein, and of particular interest are those having medical or biological uses, for example, tissue adhesives used for wound closure or space or for prostatic coupling or to provide substrates to deliver biologically or medically active materials, v. g. , microencapsulated drugs with local action, nutrients or other assets. The applicator is well suited particularly for supplying a two-component interactive fluid system such as a two component adhesive system, especially where the unmixed components have relatively low viscosities, as compared for example with a two-component epoxy resin system and Hardener Examples of such fluid systems with lower viscosity include two component adhesive systems for fabrics, especially fibrin adhesive systems such as those described in the parent application 08 / 838,078 comprising a fibrin component and a thrombin component, and synthetic equivalents. of them, as is known to those skilled in the art. Also, if desired, the applicator can be used to deliver single or multiple component systems for other purposes, v. g. , to avoid adhesion to tissues, for example in abdominal surgery, anastomosis or other surgeries.
Most of the novel applicator components can be interpreted as plastic moldings of resin materials or polymers, whose selection of suitable ones will be apparent to those skilled in the art, as will alternate materials such as metal alloys, sintered or the like. Some examples of suitable polymeric materials are: for the toothed rack 50, the pawl 48, the trigger link 46, the anchor link 44, the barrel 40 of the syringe, a polyetherimide, such as, for example, resin 1000 ULTEM (brand commercial) from General Electric Company., for trigger 22, cover 26, valve button 24, body housing 16, nozzle housing 18, an ABS resin (acrylonitrile-butadiene-styrene), such as , for example, the resin LUSTRAN 648 (trade mark) of Bayer AG., and for the suction pipe 12, assortment tube 14 and barrel 40 of syringe a polypropylene, such as, for example, PRO-FAX SR-857M ( trademark) of Montel. Although the dimensions are not critical, and modalities not suitable for fastening with one or both hands, are not contemplated, a modality that is well suited particularly for use by a surgeon, which is comfortable, light and manageable with precision, has a body length of the housing 16 of the body (without the nozzle housing 18) of approximately 15 cm and a length of reservoirs 30 of approximately 5.5 cm with a corresponding extension of the toothed area of the zipper 50 sufficient to accommodate a trip of approximately 5.5 cm. With circular cylindrical tanks of approximately 0.9 cm in diameter the capacity of the tank is approximately 3 cc, each one, in total 6 cc for the two tanks 30. Such dimensions as these give an applicator that is comfortable and ergonomic to be used with precision . Preferred constructions can vary these dimensions up to about 10, or less preferably 20 percent. Less demanding applications may vary the given or corresponding dimensions by up to about 50% while still providing an applicator that can be supported and manipulated properly with one hand. The operation of the drive mechanism is as follows. In the (raised) rest position of the trigger 22, the influence of the return spring 55 acting on the trigger link 46 causes the tie spring 100 to fall flush on the rail 104 so that the hook 92 of the catch 48 get up freeing yourself from the rack cog 50. The trigger 22 can be depressed repeatedly, until the rack 50 is advanced completely forward and the tanks 30 are completely depleted. The trigger 22 is returned to its rest position, raised by the return spring 55 when it is released, and its trip can be described as having a downward stroke and a return stroke, the downward stroke being further described as having a phase start and a termination phase. When the trigger 22 is initially depressed, in the start phase of the downward stroke, by the user, or possibly, by mechanical or electrical actuation, the force applied to the trigger link 46 to the joint 54 pivots the seal around the fulcrum pins 96, opening the angle between the tie spring 100 and the cavity 98, while working against the elastic action of the tie spring 100. Initially, the hook 90 moves downwardly to engage with the toothed rack 50, and the strap spring 100 falls flush on the rail 104. Further movement of the trigger 22, in the termination phase of the downward stroke advances the ratchet 48 forward, removing the rack 50 together with it, as the ratchet hook 92 engages the teeth 108 of the rack and the sound tone transmitter 127 as it travels on the teeth 108 of the rack. The rack 50 is interconnected with the double syringe 40 by the key 120 locked in the bag 122, so that the double syringe 40 is also advanced forward, urging the plungers 42 forward in the reservoirs 30 to dissipate fluid therefrom. The finishing phase of the stroke ends either when the force exerted by the user on the trigger 22 is inadequate to advance the pistons 42, or the notches 61 on the sides of the trigger 61 engage with the arrow 66 stopping the travel of the trigger. While the user maintains pressure on the trigger 22, the return flow is prevented by the inter-coupling of the double syringe 40 with the rack 50 and the teeth 108 of the rack with the hook 92. When the trigger is released, the springs 100 of taut act quickly to rotate the pawl 48 and raise the ratchet hook 92, uncoupling it from the rack 50 while the return spring 55 pulls the trigger link 46 towards the anchor link 44, raising the trigger 22 and carrying the pawl 48 backwards, in preparation for a repetition stroke, with the ratchet hook 92 traveling in silence, free above the teeth 108 to its rearmost position under the cover tab 119 where it is pushed down to be fully engaged with the teeth 108 of zipper. In the meantime, as previously stated, the tone emitter 127 holds the zipper 50 against backward movement. Accordingly, the cover 26 can be opened by pivoting the tone emitter 127 out of engagement with the rack 50 and releasing the ratchet finger 88 from the engagement with the tongue 119, the housing 18 of the mouthpiece can be removed and the deposits 30 they can be filled from a suitable fluid supply system (for example as described in the parent application 08 / 838,078) by removing the indicator bar 114, by hand, in the backward direction. Referring to FIGS. 6 and 7, some of the forces that come into play when a user presses the trigger 22 are shown symbolically for illustrative purposes and to model the operation of this embodiment of the inventive mechanism of the applicator driver. Analyzes and descriptions of other vectors may be made, as will be apparent to those skilled in the art, and the invention does not depend on the accuracy, in practice, of the conclusions reached, having in mind, in particular, the various assumptions and approximations. that are necessarily done. The following description is included to aid the understanding of the invention and to apply the teachings herein to the practice of the invention.
The manual (or other) force a user applies to the trigger is assumed to be suitably represented as a force F, at a distance Li from the pivot pin 58 of the trigger, which will generate a moment F1 L1 about the pivot pin 58. Ignoring the friction losses and others, the platform 60 which engages the hinge 52 converts the received impulse into a force F2 in a direction perpendicularly about the pivot pin 58 at a distance L2 from the pivot pin 58, said distance being determined by the location of platform 60, such that the moments are equal, that is, so thatF, -L, = F2 L2 and F2 = F, (L? / L2)There is consequently a mechanical advantage by which the force F2 is amplified by the ratio of the length ^ to the length L2. Thus, a designer, or engineer, can increase this advantage by increasing the length L1 of the trigger 22, or by decreasing the distance L2 of the platform 60 from the pivot 58, said distance will decrease, however, the distance traveled by the ratchet 48 in each stroke of the trigger 22. The force F3 transmitted along the link 46 of the trigger, from the point of contact of the platform 60 with the pivot 52 to the joint 54, will be F2-cos a where a is the angle between the directions of forces F2 and F3. (The value of the cosine decreases of course when the angle increases, although not proportionally). The force F exerted on the ratchet 48, in its direction of travel, will be F3 cos ß where ß is the acute angle between the directions of the forces F3 and F4. Substituting F2 and F3, it is as follows:F4 = F! (L? / L2) eos a eos ßAs stated earlier, this conclusion necessarily involves approximations and assumptions. The operating characteristics of the drive mechanism depend to a large extent on the placement and nature of the connection between the trigger link 46 and the trigger 22. In mechanisms such as those described in the parent application 08 / 838,078 a trigger link (arm 1 10 in the same) is pivotally connected to the trigger 22 (105) at a point relatively distant from the pivot 58, providing a modest mechanical advantage which, depending on the particular geometry employed, tends to increase as the trigger 22 is depressed, because the product of cos ay cos ß increases. Thus, the angle β decreases more quickly than can be compensated for by increases in the angle β and the corresponding decrease in its cosine. It would be desirable to provide a greater mechanical advantage in the start phase of the stroke to more quickly overcome the initial losses by friction, or sticking, and inertia, and to provide smoother operation and feel. The mechanical advantage can be increased by relocating the point of attachment of the trigger link 46 to the trigger 22 so that it is closer to the pivot pin 58. One difficulty with this solution is that the possible degree of travel of the joint 54, and hence of the ratchet 48, is significantly reduced. Another difficulty is that the angles a and ß have unfavorable values from where the additional trip of the trigger 22 results in an increase in the product of its cosines, increasing the mechanical advantage. Such an increase in mechanical advantage adversely affects the ability to control the applicator and can cause the fluid to sputum unintentionally. The invention solves these problems by decoupling the trigger link 46 from the trigger 22, securing it to the anchor link 44, and allowing the hinge 52 to float or slide on the platform 60 in a direction away from the pivot axis through the pin 58 of pivot. The start phase of a trigger actuation stroke provides an excellent mechanical advantage since the hinge 52, at the rear end of the platform 60 is coupled by both the platform 60 and the stop 67, applying a driving force along of the trigger link 46. In this point, Figure 6, L2 is relatively small, possibly a half of Li, the angle OH is small and the angle $ has an intermediate value. As the trigger stroke continues downward with its termination phase, the hinge 52 moves forward along the platform 60 increasing the length of L2 and increasing the angle a2 whose effects together reduce the mechanical advantage and, with suitable selections of the length and position of the anchor lever 44, may be sufficient to overcome the effect of the concomitant increase in the angle ß. The characteristics of the tension spring 55 are selected to provide adequate strength and to ensure that it provides a satisfactory means of recovery, the trigger actuating mechanism returning to its rest position. The result is a diminishing mechanical advantage, a good feel for firing action and an applicator that can be precisely controlled and used to fill and apply small amounts of fluid accurately to desired locations. Such a mechanism is of particular value for a tissue adhesive applicator for surgical and microsurgical uses. These beneficial results are at least partially attributable to the use of a sliding pivot, 54, which has some limited freedom of translation movement, relative to the trigger 22 against simply being pivotally attached to the trigger 22.
This freedom of movement is provided by the cooperating action of the anchor link 44 and the platform 60. As illustrated, by way of example, the anchor link 44 may be approximately half the length of the trigger link 46 and its pivoting point 70 for joining the housing 16 of the body can be vertically between the pivot pin 58 and the joint 54, and move a small distance backwards from the stop 67 so that the anchor link 44 is inclined forwardly at the resting position. Other constructions that provide some or all of the benefits of the invention will be apparent to those skilled in the art in light of the teachings herein. For example, the trigger 22 could be as a button with a reciprocal linear travel to the housing 16 of the body while having camming surfaces to provide the desired lateral travel of the hinge 52. Another means can be provided to guide the upper rear end of the body. trigger 46 link. Thus, it could carry one or more projections running in slots or rails suitably formed in the trigger 22. The pawl 48 could be replaced by a friction roller that engages an extension of the rack 48, through adjustments to the geometry or means to accommodate the extension would be desirable. Similarly, the pawl 48 could engage the rack 50 frictionally.
INDUSTRIAL APPLICABILITY The present invention is particularly suitable for application in surgical devices and medical or veterinary treatment industries, but has wide application in many industries where the controlled application of small amounts of one or more fluids is desirable. Although some illustrative embodiments of the invention have been described above, it is understood, of course, that various modifications and equivalences of the embodiments described will be apparent to those of ordinary skill in the art. Some equivalences will be easily recognized by those of ordinary skill while others will require no more than routine experimentation. Such modifications and equivalences are within the spirit and scope of the invention, which is limited and defined only by the appended claims.