Abstract: A device for humane injection of fluid into animals from a distance is disclosed. The device comprises a hollow body with a primary chamber suitable for holding the fluid to be injected, a hollow needle at the forward end of the hollow body, a disposable tag attached to the forwardmost surface of the hollow body, and a remote retrieval means. The device may be projected toward the target animal by any of several conventional methods including compressed gas or chemical explosion gun. Upon impact with the target animal a trigger mechanism which comprises a ball and valve seat check valve is tripped allowing a resilient means to force the fluid through the needle and into the animal. The device is held in place during the injection process by an adhesive means on the forwardmost surface of the tag. After injection the device is pulled form the animal using the retrieval means. The tag separates from the device and remains attached to the skin marking the animal.

Abstract: A needleless injection system and method for injecting a medical product comprises a needleless injection device having a nozzle assembly defining an ampule chamber for holding medication, an energy device for pushing medication out of the nozzle assembly, and an energy device actuating mechanism. These components are operatively contained in a housing configured for a hand held operation. The energy device is a self-contained gas spring operatively connected to a plunger operating within the ampule chamber. The gas spring is preferably stepped which can be used in many different applications, an air gun being one. The injection device can be provide with a coupling device for coupling a medication supply vial to the nozzle assembly. The nozzle assembly is removably situated in the housing with the plunger removable therewith.

Abstract: A syringe actuation device comprises an internally-threaded hollow outer sleeve with an open proximal end, and an externally-threaded hollow cylinder with a tapered internal diameter, that encloses a spring-biased piston, and that threads into the open distal end of the sleeve. The outer sleeve has a longitudinal opening parallel to its axis for receiving the fully-extended plunger of a pre-filled syringe, and a distal wall portion through which the barrel of the syringe extends. The cylinder contains a coil spring extending axially within its hollow interior, the spring having a proximal end seated against a proximal end wall of the cylinder, and a distal end attached to the proximal side of the piston. The piston is attached to the distal end of the spring so as to be pivotable from a canted orientation with respect to the cylinder's axis when the spring is compressed, to a substantially coaxial orientation with respect to the cylinder's axis when the spring is extended to a less compressed state.

Abstract: An injector (10) having a needle (14) which is exposed by a retractable shroud (13). Mounted within the body (11) of the injector (10), is a first interacting piston (30) and cylinder (31) which cooperate to enclose a first space (33) which receives the liquid to be injected. A second interacting piston (26) and cylinder (27) cooperate to enclose a second space (28). A gas under pressure is delivered to the second space (28) to cause movement of the second piston (26). The second piston (26) is attached to the first piston (30) and therefore moves with it. The shroud (13) is operatively associated with a valve (35) to regulate the delivery of the gas under pressure to the space (28) to cause operation of the injector (10). A user of the injector (10) grips the body (11) by means of a handle portion (12) and presses the injector (10) against the skin of the animal. This causes retraction of the shroud (13) as the needle (14) penetrates.

Abstract: A multi-cartridge dispenser for delivering two liquid medications through a single needle. The dispenser includes independent dual channel metering mechanism, dual channel drive mechanisms, and dual channel lock and pullback mechanisms. The wing must be in its "up" position for metering to take place. The wing reciprocatingly moves a driver between a pre-injection position and a post-injection position to reciprocatingly advance the leadscrews upon an injection stroke. The dosage indicator automatically rotates to its initial zero position upon the injection stroke. The lock and pullback mechanism automatically prevents rotation of the leadscrew upon metering and injection. It also locks out the cartridge retainers so that the retainers can be removed from the housing only while the wing is in its "down" position. The pullback sleeve unloads a pullback key during a cartridge change in order to enable the leadscrew to be spun freely back to its home position.

Abstract: An automatic injector for the separate storage of a solid and a solvent for this solid. The injector comprises a discharge mechanism, a cartridge assembly and a front cover which is connected to a front portion of the cartridge assembly and provided at its front with a pierceable central area. The cartridge assembly comprises a hollow barrel, a pierceable stopper connected to the front portion of the barrel and constituting a compartment in front of said stopper for accommodating the solid, a piston slidably accommodated in the backward portion of the barrel and constituting a compartment for liquid in the barrel, an injection needle longitudinally extending in the liquid compartment, and means for centering the distal end of the needle in order to position the needle tip towards the pierceable stopper. The front cover is capable of rotational movement relative to the outer sleeve to allow the liquid in the barrel to reach the solid compartment through the needle.

Abstract: A hypodermic fluid dispenser and a collapsible body for the hypodermic fluid, with a hypodermic needle injecting the fluid once sufficient pressure is applied to collapse the body. There is also disclosed an electrical hypodermic fluid dispenser having a reusable, rechargeable power source, and a reservoir from which hypodermic fluid can be withdrawn for injection through a single injection orifice.

Abstract: An automatic injector training device comprises an outer structure having i) a rearward end, ii) a forward end arranged to be engaged with an injection site of the user, and iii) an intermediate portion. A manually movable actuating member is movable between a storage position and an activated position by being manually depressed by the user. A prod member is movable within the outer structure between a retracted position and an outwardly extending position when the actuating member is manually moved between the storage position to the activated position. A spring member is disposed within the outer structure and arranged so as to move the prod member from the outwardly extending position to the retracted position when the actuating member is moved from the activated position to the storage position.

Abstract: A sustained release capsule adapted to be inserted into the rumen of a ruminant animal and means for retention of the capsule in the rumen.

Abstract: A liquid preparation of a pharmaceutically active agent having a defined composation is repeatedly dosed from a multi-dose container having a defined volume. The amount dosed is selected as 1/N of the volume of the multi-dose container, N being an integer having a value of 2 or higher.A device for dosing a liquid preparation comprises a holder (1) for a multi-dose container (2), which has a movable rear wall (5) acting as a piston for expelling the liquid preparation (6) from the container, and a piston rod (7), which is provided with releasable blocking means (11, 14, 19, 22), such that the movement of the piston rod is limited to a preset length (35) corresponding to an expelled volume of 1/N of the volume of said multi-dose container, N being an integer having a value of 2 or higher.A preferred embodiment of the device is as an injection device for repeated parenteral injections from an injection cartridge.

Abstract: A reloadable automatic or manually usable medicine injection apparatus having a barrel which receives a syringe subassembly. The syringe subassembly includes an ampule for housing fluid medication, a needle, a plunger stopper, and plunger shaft which allow removal and manual use. The injection apparatus includes a driver for forcing the syringe subassembly to inject the needle and displace fluid medication. The injection apparatus preferably includes a trigger handle, sheath remover, and removable stop system for delivery of multiple doses.

Abstract: A laparoscopic irrigation system and bottle pump for controlling a source of gas pressure driving a source of irrigation solution that includes a monitor for monitoring the source of gas pressure and indicating when the gas pressure falls below a predetermined value. Also, the liquid level of the source of irrigation solution is monitored via infrared radiation and when the level falls to a predetermined value it is detected, a visual and an audible signal is actuated and an alternative source of irrigation solution is selected. Further the level of gas pressure driving the source of irrigation solution is controllable with an electronic circuit containing a stepping motor mechanically connected to a pressure regulator.

Abstract: The invention is a pre-charged, disposable syringe capable of use by patients. The syringe has a housing with a cover having a central aperture which receives an actuator button. The actuator button extends to an internal piston which is mounted over a medication ampoule. The ampoule has a dependent hypodermic needle which is slidably received in the housing and moves between recessed and projected positions. In its recessed position, the ampoule is totally contained within the housing, and in its projected position, the hypodermic needle projects from the housing. The housing contains an actuator spring, which is compressed and biased to move the piston and the ampoule into its projected position. The medication is discharged from the ampoule by the mechanically coupled piston, or by the release of air from an internal air pressure chamber.

Abstract: A needleless injector for providing medication provides improved flow rate with a reduced pressure head. The injector includes discharge member having a rounded or sloped jet orifice, a milled valve member, and a check valve, which provide for increased shot velocity, reduced time of the shot and increased flow.

Abstract: A device for automatically injecting a material into the body is disclosed. The device includes a drive assembly and a syringe assembly which is mounted to the drive assembly. The drive assembly includes a drive rod, a driver releasably coupled to the drive rod, and a constant force spring which urges the drive rod towards the syringe assembly. The spring first urges the coupled drive rod and driver along the axis of the device, causing the skin to be penetrated by the needle of the syringe assembly. The drive rod is then decoupled from the driver. The spring continues to urge the drive rod in the axial direction, whereby the drive rod engages a piston in the syringe assembly and causes the displacement of the material therein.

Abstract: A reloadable automatic injector comprises a reusable power pack assembly for effectuating multiple injection operations. The power pack assembly includes an outer body and an energy releasing assembly disposed within the body. The energy releasing assembly is capable of providing multiple energy releasing strokes. A disposable cartridge assembly is provided which is engageable with the power pack assembly and forms an elongate injection assembly therewith. The cartridge assembly is adapted to receive energy from the power pack during one of the energy releasing strokes. The cartridge assembly includes a housing in which a charge of medicament and a needle is contained. A plunger is disposed within the housing for forcing the medicament through the needle.

Abstract: A disposable, automatic, injector is disclosed which allows self-administration of a medicament to be injected subcutaneously. The injector comprises a barrel (1) with an inner chamber bounded by a liner (2). A first piston (4) and a second piston (11) are provided which may slide within the chamber with a fluid-tight seal with the liner (2). The second piston (11) carries an injection needle (13). A drive means, comprising a compression spring (5) and a releasable retaining collet (6), is provided to act on the first piston (4) to drive it towards the second piston (11). In operation, the drive means urges the first piston towards the second (11). The injection fluid, initially stored between the first and second pistons is incompressible and causes the second piston (11) to move until the needle (13) projects from the end of the barrel (1).

Abstract: A medical solution delivery system comprises a cylindrical container having an opening at one end and a port for a medical solution at the opposite end; a plunger slidably arranged in the container; a plunger-driving device for forcing the plunger to move towards the port of the container to deliver a medical solution therethrough; a capsule for holding the container, the plunger and the plunger-driving device; and a flow control device connected to the port of the container to control a flow rate of the solution delivered therefrom. The solution in the container is delivered through a flow control device connected to the port of the container.

Abstract: A dispenser (2) includes a body (4), a needle (110) and one or more hollow cylinders (28) and pistons (144). The needle is movable between predelivery position and a delivery position, at which the inner needle end (112) opens a ball check valve (142) to permit free fluid flow from the cylinder, along a flow path (46) and through the needle. A threaded dose adjuster (164, 166) is mounted within the body and engages a threaded stem (150). The stem is prevented from rotating so that a rotation of the dose adjuster in one direction causes the dose adjuster to move axially away from the piston to compress a drive spring (176) and preload the stem. Moving the needle assembly to the delivery position causes the dose of pressurized pharmaceutical to be automatically driven from the cylinder and through the needle. The cylinder can be refilled by the user through the needle by opening (88, 92, 94) a supplemental pathway (54, 52) and rotating the dose adjuster in the opposite direction.

Abstract: A reloadable medicine injection apparatus having a barrel which receives a replaceable, disposable syringe subassembly. The syringe subassembly includes a cartridge having an ampule for housing fluid medication, a needle, and a plunger stopper. The subassembly also has a detachable plunger shaft coupled to the stopper. The reloadable injection apparatus includes a driver for forcing the syringe subassembly to inject the needle and displace fluid medication.

Abstract: Disclosed is a fluid delivery system comprising a bladder to hold a fluid, the bladder being enclosed in a structure formed from a cap connected to a drive mechanism. The drive mechanism includes a piston driven by a constant force spring, the piston resting against the bladder. Activation of the drive mechanism delivers the fluid at a rate pre-determined by the design of the spring.

Abstract: A facilitated procedure for attaching single-use syringes, one at a time, to an intravenous (IV) pump in which each syringe is mounted in the path of the IV pump plunger by clips and within a clear plastic syringe-holding sleeve that overlies the volumetric graduations of the syringe to permit visual monitoring of the exiting flow, and permits an operating mode using plural prefilled syringes for IV therapy using the same IV pump.

Abstract: A single use needleless hypodermic injector includes an elongate housing with a proximal end, a distal end, an axis and a hollow bore therethrough. The housing has a reservoir at the distal end with a generally cylindrical chamber for containing an injectable liquid. The chamber has a axis aligned with the housing longitudinal axis. The chamber has a first open end adjacent the housing with a resilient stopper mounted therein. The reservoir has a distal second end with an orifice in fluid communication with the chamber. The resilient stopper seals the chamber and ejects the liquid from the chamber, forming a stream at the orifice when the stopper is moved distally in the chamber. The injector has an piston mounted for axial movement within the housing bore and elements to axially bias the piston distally within the bore. The piston has an armed position wherein it is positioned proximally within the bore.

Abstract: An automatic pharmaceutical dispensing syringe (2), includes a main barrel (4) having hollow interior (18) sized to house a conventional pharmaceutical cartridge (16) and needle (6). A cap (6) at one end (8) of the main barrel is used to rotate a threaded dosing screw (158) housed within the main barrel. The dosing screw is permitted to move axially within the main barrel. The dosing screw threads (156) engage similar threads (146) on an elongate piston driver (140) which abuts the cartridge piston (152). A brake pad (194) secures the piston driver to the main barrel while the cap is rotated to select the desired dose. Doing so causes the dosing screw to move axially relative to the piston driver to compress an injection spring (174). The injection sequence is begun by placing the distal end (114) of an outer sleeve (10) surrounding the main barrel against the patient and pressing a trigger (130).

Abstract: A method of manufacturing flexible thick-wall capillary tubing, comprising the steps of extruding a plastics sheath around a filament of uniform diameter, and withdrawing the filament from the sheath to form a length of tubing having a capillary bore which has been defined by the filament. The method enables the manufacture of fine-bore capillary tubing having a tightly controlled bore diameter.The invention also provides a method of low flow rate metering of a liquid by utilising a length of such tubing as a flow restriction, and apparatus for carrying out the method. This method and apparatus are particularly suited to controlling very low rates of flow of drugs or other injectable liquids to a patient over a prolonged period, in an arrangement which can readily be carried on the patient's arm to alow the patient mobility while being injected.

Abstract: A hypodermic fluid dispenser and collapsible cartridges having fluid-holding chambers therefor includes an insertor device for moving the cartridges into the dispenser, a resilient device for collapsing the cartridges, a motor energizing the resilient device and a source of electrical energy for the motor.

Abstract: The present invention relates to an injection device for the automatic injection of at least one injection liquid, comprising an assembly of a discharge mechanism, a cartridge holder and a cartridge slidably accommodated in the cartridge holder, the discharge mechanism comprising an outer sleeve wherein the cartridge holder is slidably adapted. A protective cover is provided on the front of the device, covering the front portions of the cartridge holder and the outer sleeve in such a manner, that unintentional backward movement of the cartridge holder in the outer sleeve, resulting in activation of the device, is prevented.

Abstract: A device (10) for rapid vascular drug delivery, particularly through the adult sternum or the pediatric tibia, incorporates a cylindrical syringe body (12), fitted with a needle (14). The syringe body is held in a cylindrical main housing (16) having a front barrel (18) with an orifice (20) through which the needle (14) may be extended. A cylindrical actuation handle (22) fits over end (24) of the main housing (16) for sliding movement along the main housing. A syringe plunger (26) contacts drive plunger (28) and extends into the syringe body (12) from end (30) to confine liquid medication (32) in the syringe body (12). A main spring (34) extends between the drive plunger (28) and the actuation handle (22) to bias the actuation handle (22) in its extended position. A needle return spring (38) extends between the front barrel (18) and the syringe body (12) to bias the needle to its retracted position.

Abstract: A negator spring-powered I.V. pump of compact size resulting from imparting a non-circular, rather than a linear configuration to the negator spring; the non-circular configuration taking up less size or linear dimension which, added to the linear dimension of the syringe of the pump, results in an optimum reduced overall pump size that is convenient for portable ambulatory I.V. therapy.

Abstract: Osmotically driven delivery capsules which include a beneficial agent and a water absorptive osmotic engine in separate compartments separated by a movable partition are designed to deliver the beneficial agent in a pulsatile manner through an orifice. The pulsatile delivery is achieved by a series of stops along the inner wall of the capsule which obstruct the movement of the partition but which are overcome in succession as the osmotic pressure rises above a threshold level. The number of stops and their placement longitudinally along the length of the capsule establish the number and frequency of the pulses, and the configuration of the partition controls the pulse intensity.

Abstract: A remote injection device for animals comprises a barrel with a piston slideable within the barrel from an initial retracted position at one end of the barrel forwardly toward the opposed end of the barrel to discharge liquid in an injection action through a needle at the forward end of the barrel. The piston is held in a retracted position by an O-ring on a release member which projects through an O-ring carried on the inside surface of the barrel. The inner diameter of the O-ring on the barrel can be adjusted by axial movement of the pair collars on the inside of the barrel. This adjusts the amount of force necessary to push the release member O-ring through the outer O-ring to release the piston to be moved by spring to the discharge position. The barrel can be mounted either upon an arrow type projectile so the impact forces are sufficient to release the piston upon engaging the animal.

Abstract: An implantable drug delivery system includes a housing having a base end and a discharge end, for holding drug solution at the discharge end, a valve disposed at the discharge end to allow a drug solution to flow from inside the housing, through the valve and out of the housing when solution pressure is applied to the valve, a piston slidably disposed in the housing to slide between the base end and discharge end to force solution toward the discharge end and out the valve, and a spring disposed in the housing between the piston and the base end thereof for urging the piston toward the discharge end. A plurality of different length tethers are connected at one end to the piston and at the other end to a respective release node located at the base end of the housing. Each release node holds the other end of a respective one of the tethers until a release signal is received at which time it releases the tether.

Abstract: A medical liquid injector for continuous transfusion includes a syringe fitted with a piston having a detachable shaft rod, and a cap that can be connected to a proximal end portion of the syringe. The cap has an elastic pressing device for continuously pressing the piston from which the shaft rod is removed to a position where all the amount of medical liquid is pushed out after the medical liquid has been sucked into the syringe.

Abstract: A device (10) for rapid vascular drug delivery, particularly through the adult sternum or the pediatric tibia, incorporates a cylindrical syringe body (12), fitted with a needle (14). The syringe body is held in a cylindrical main housing (16) having a front barrel (18) with an orifice (20) through which the needle (14) may be extended. A cylindrical actuation handle (22) fits over end (24) of the main housing (16) for sliding movement along the main housing. A syringe plunger (26) contacts drive plunger (28) and extends into the syringe body (12) from end (30) to confine liquid medication (32) in the syringe body (12). A main spring (34) extends between the drive plunger (28) and the actuation handle (22) to bias the actuation handle (22) in its extended position. A needle return spring (38) extends between the front barrel (18) and the syringe body (12) to bias the needle to its retracted position.

Abstract: A medical apparatus for injecting or withdrawing biological or therapeutic fluid includes a syringe body defining a syringe cavity into which fluids can be introduced or withdrawn by way of a fluid port and a vacuum port. A piston is positioned for reversible movement in the syringe cavity between the fluid port and the vacuum port so that movement of the piston in response to a decrease in fluid pressure causes a resilient element positioned within the cavity to be compressed. The compressed spring provides a store of mechanical energy that can be used to drive the piston toward the fluid port and expel fluid contained in the first cavity through the fluid port when pressure within the syringe cavity is equalized. Control of vacuum and air inlet into the syringe cavity is conveniently controlled by a dual port valve connected to the syringe body.

Abstract: An intraruminal device for controlled release of a drug formulation in the rumen of an animal, comprises an open-ended tube for containing the drug formulation, a piston adapted to travel longitudinally within the tube and biased so as to deliver the drug formulation through the open end of the tube. Travelling with the piston is an associated weight adapted to retain the device within the rumen during delivery of the drug formulation.

Abstract: An injection device (1) has a housing (2) in which is arranged a holder for a deformable, medicament-containing ampoule (4). To a frontal end region is linked an injection needle (5) which communicates with the interior of the ampoule and with a driving device linked to the other frontal end region of the ampoule, opposite the frontal end region facing the injection needle. The ampoule (4) is arranged and held within a support device (13) that extends between both frontal end regions.

Abstract: Patient controlled analgesic (PCA) infusion apparatus and method are disclosed, in which a liquid desired to be self-infused into a patient is controllably supplied from a positively pressurized supply reservoir to a lower pressure dose chamber of a patient operable syringe from which the patient may expel the liquid and infuse such into a suitable infusion site, as through a cannula inserted into the patient, the supply of liquid from the reservoir to the dose chamber being controlled by a flow control metering tube assembly which provides a selected flow rate for a reference fluid and reference pressure differential. A vacuum-induced void is created in the dose chamber after each infusion by the patient in order to aid in effecting a desired substantially constant pressure differential between the pressurized supply source and the dose chamber, so as to effect a desired selected substantially constant refill flow rate of liquid from the supply reservoir and into the dose chamber.

Abstract: In a hypodermic syringe (10) with a hypodermic needle (20) which is adapted to be extended from a needle space (19) from a readiness position into an operative position by a force storage means (28), the invention seeks to make it possible to render the hypodermic needle (20) inaccessible after use. For that purpose the hypodermic needle (20) is arranged to be returned from the operative position by a force storage means (62) into the needle space (19) or a receiving space (11), which surrounds same at least at times, for receiving the needle space (19), or it is connected to a plunger (24) which is disposed in the needle space (19) and which is provided at its end face remote from the needle with at least one retaining recess for a pulling member, the recess being accessible from the exterior.

Abstract: An improved automatic pellet carrier (100) fed pellet implanting gun apparatus (10) is described. The carrier is mounted in an opening (12b) through a front side (12c) of a retractable head (12) which is linearly moveable in a nose end (11c) of a handle assembly (11) along a longitudinal axis a--a. The carrier relies upon an internal spring (107) to automatically register a pellet (101) in a bore (12a) in the retractable head so that by actuating a trigger (14), a drive rod (23) which travels linearly along the axis a--a and through the bore in the retractable head and through the carrier, can move the pellet into the barrel (13a) of a needle (13) that has been inserted into an animal or the like. After the pellet enters the needle, the needle, the retractable head and the carrier are mechanically retracted into the gun with the carrier retracting along a slot (11f) in the nose so that the pellet is deposited in the animal, unobstructed by the needle.

Abstract: An autoinjector converted from an intramuscular to a subcutaneous mode of injection comprising a housing having a medicament cartridge assembly mounted within the housing means in a storage position for movement out of the storage position and a releasable stressed spring assembly for moving the medicament cartridge assembly means out of the storage position. The stressed spring assembly is operable in response to a manual actuating procedure which does not require compression of the subcutaneous tissue to effect an intramuscular mode of injection by moving the hypodermic needle of the cartridge assembly outwardly of the housing into the muscle tissue at the injection site of a user and a major portion of the liquid medicament of the cartridge assembly outwardly through the hypodermic needle into the muscle tissue of the user.

Abstract: The ambulatory infusion pump is provided with a preloaded spring having a fixed spring constant. A tab is provided to release the preloaded spring to impose a biasing force on the piston of the pump. The piston slides within the housing against a substantially constant friction force when moving from the filled position toward the empty position. The biasing force of the spring and the stroke of the piston are coordinated so as to maintain a pressure on the fluid being dispensed from the pump housing which decreases at a slow rate and within a range of about 15% of the referenced pressure.

Abstract: The injection device described comprises a loading element (74) which can be moved longitudinally for loading purposes and is rotatable for the purpose of setting the injection dose. Associated with this loading element (74) is a second setting element (86). The latter allows a judicious internal combination of the information supplied by the position of the loading element (74) and of the second setting element (86). The patient can effect several individually-dosed injections from a single container.

Abstract: An autoinjector particularly suited to be carried on the person of a user comprising a housing defining an exterior configuration of a size and shape approximately the same as that of a conventional fountain pen including a housing body assembly of elongated generally cylindrical configuration and a separate housing cap structure of elongated generally cylindrical configuration having an elongated clip thereon. The housing cap structure is detachably secured to the housing body assembly in open ended telescopic relation with an opposite end portion thereof preferably by a childproof connection. A medicament cartridge assembly is mounted in a storage position within a forward end of an interior chamber within the housing body assembly and a releasable stressed spring assembly is carried by the housing body assembly adjacent the rearward end thereof.

Abstract: A stressed spring assembly for providing an operative stroke in cooperating relation with a medicament cartridge assembly of an auto-injector so as to inject a liquid medicament of the medicament cartridge assembly through a hypodermic needle of the medicament cartridge assembly into an injection site of the user. The stressed spring assembly includes a cap structure serving the plural purposes of (1) facilitating the securement of the cap structure and remainder of the auto-injection with the user's pocket, (2) alleviating the likelihood of an unwanted release of the releasable mechanism of the stressed spring assembly with a resultant unwanted movement of the hypodermic needle and an unwanted movement of the liquid medicament outwardly of the hypodermic needle by requiring two different manual movements for its removal, and (3) protecting against an unwanted contact with the hypodermic needle while in extended operative position after withdrawal from the injection site.

Abstract: Needle and high velocity jet hypodermic injectors employ a tubular liquid chamber, a suitable output port i.e., a needle or a jet port, and corresponding means for applying pressure to collapse the liquid chamber.The needle injector includes a needle sheath which automatically covers the needle after use and inhibits reuse of the needle. The jet injector electronically controls and monitors the system parameters of operation to assure successful injection results.

Abstract: A method of administering post-operative anesthesia directly to the surgical site through a catheter introduced into the site during the post-operative procedure. The flow of medication into the catheter is regulated by a micro-bore cannula that insures delivery at very small rates. The plunger of a spring-loaded syringe creates the pressure that causes the medication to flow through the cannula and catheter into the wound. Because of the spring's nonlinear characteristics within the range of stroke of the plunger, the pressure exerted on the liquid gradually decreases with the expansion of the spring. By appropriately sizing the spring and the inside diameter of the cannula, a device is developed that administers the required dosages of anesthetic continuously and at decreasing rates.

Abstract: A device for subcutaneous injection without a needle comprising an injection head (12) including a plurality of injection holes (38) having a diameter of less than about 100 microns, these holes being parallel to one another and being formed at the ends of larger-diameter oblique cylindrical ducts (42) made through the thickness of the injection head.

Abstract: A method of administering post-operative anesthesia directly to the surgical site through a catheter introduced into the site during the post-operative procedure. The flow of medication into the catheter is regulated by a micro-bore cannula that insures delivery at very small rates. The plunger of a spring-loaded syringe creates the pressure that causes the medication to flow through the cannula and catheter into the wound. Because of the spring's nonlinear characteristics within the range of stroke of the plunger, the pressure exerted on the liquid gradually decreases with the expansion of the spring. By appropriately sizing the spring and the inside diameter of the cannula, a device is developed that administers the required dosages of anesthetic continuously and at decreasing rates.

Abstract: A negator spring-powered I.V. pump of compact size resulting from imparting a non-circular, rather than a linear configuration to the negator spring; the non-circular configuration taking up less size or linear dimension which, added to the linear dimension of the syringe of the pump, results in an optimum reduced overall pump size that is convenient for portable ambulatory I.V. therapy.