US20050192541A1 - Safety syringe needle device with interchangeable and retractable needle platform - Google Patents

Abstract

The syringe includes a barrel, a plunger, and an adapter for mounting the needle in the distal end of the barrel. The adapter includes a protrusion projecting away from the needle end and into the barrel defining an annular space between the barrel and the protrusion. The plunger and protrusion have complementary surfaces whereby the plunger may grip the adapter for removal of the adapter into the interior of the barrel after use. These complementary surfaces afford initial resistance to further axial movement of the plunger toward the adapter, signalling the user that further axial pressure will permanently lock the plunger and adapter to one another whereby, upon application of full axial pressure on the plunger, the complementary surfaces of the plunger and adapter permanently lock to one another to enable joint unitary movement of the plunger and adapter together with the needle carried by the adapter into the barrel. The adapter includes vent passages communicating between the central passage through the adapter and the annular space whereby air can be vented from the barrel after receiving fluid within the barrel and prior to injection. Thus, the syringe may be oriented in a vertical position needle end uppermost with the vent passages forming the most superior portion of the barrel interior whereby air may be vented.

Description

RELATED APPLICATIONS
• This application is a continuation-in-part application of application Ser. No. 08/603,868, filed Feb. 22, 1996, which in turn is a divisional application of application Ser. No. 08/470,026, filed Jun. 6, 1995, now U.S. Pat. No. 5,520,649, issued May 28, 1996, which was a divisional application of application Ser. No. 08/361,227, filed Dec. 21, 1994, now U.S. Pat. No. 5,462,531, issued Oct. 31, 1995, which was a continuation-in-part application of application Ser. No. 08/128,694, filed Sep. 30, 1993, now U.S. Pat. No. 5,415,638, issued May 16, 1995, which in turn is a continuation-in-part application of application Ser. No. 07/909,385, filed Jul. 9, 1992, now U.S. Pat. No. 5,263,933, issued Nov. 23, 1993, which, in turn, is a continuation-in-part of application Ser. No. 07/800,849, filed Nov. 29, 1991, now U.S. Pat. No. 5,205,827, issued Apr. 27, 1993, which is a divisional of application Ser. No. 07/687,108, filed Apr. 18, 1991, now U.S. Pat. No. 5,112,318, issued May 12, 1992, which is a continuation-in-part of application Serial No. 607,127, filed Oct. 3, 1990, now U.S. Pat. No. 5,122,124, issued Jun. 16, 1992, which is a continuation-in-part of application Ser. No. 07/410,318, filed Sep. 21, 1989, now U.S. Pat. No. 5,030,208, issued Jun. 9, 1991, which was a continuation-in-part of application Ser. No. 07/327,344, filed Mar. 22, 1989, now abandoned, which was a continuation-in-part of application Ser. No. 07/285,012, filed Dec. 14, 1988, now abandoned, the disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
• This invention relates to a novel safety disposal syringe needle device which has medical and industrial application. More particularly, this invention pertains to a syringe which, after being used by a person to inject medication or fluid into a patient, or withdraw fluids from a patient after sampling or exposure to toxic materials, or the like, can be transformed by the person to withdraw the needle into the barrel of the syringe for disposal purposes, thereby eliminating needle stick injuries among such persons.
BACKGROUND OF THE INVENTION
• Needle stick injuries among medical personnel such as health care workers are of growing concern because of disease transmission, particularly the deadly virus known as HIV-1 (AIDS) and Hepatitis B. The AIDS virus for which there is no known cure is estimated to infect more than twenty million people worldwide and is spreading rapidly. Although in 1985 medical publications stated that no health care workers had become infected with the AIDS virus, it is now known that there is a significant risk to health care workers. A report in the New England Journal of Medicine, Aug. 14, 1988, indicates that the risk of acquiring HIV-1 infection is 0.35-0.74% per needle stick injury. The reported incidence of needle stick injuries to medical staff has been reported at 25.3 per 100 beds annually. In one New York hospital, at least 7% of house doctors have sustained needle stick injuries while caring for AIDS patients.
• Transmission rates of Hepatitis B after needle stick exposure are much higher than that occurring with the HIV virus and may be 6-30%. The Center for Disease Control has estimated 200-300 health care workers die annually in the U.S.A. from occupationally acquired Hepatitis B.
• With presently used syringes with projecting needles, potentially dangerous needle stick in juries are commonplace and most often occur between the time the medication is injected into the patient and the time the syringe is disposed of. Most injuries occur while recapping the needle or when disposing of it into a disposal container. However, maintenance personnel who handle disposed materials are also subject to needle stick injuries.
• At present, there is no reason to believe that the AIDS epidemic will come to a quick end. Canada's frequency rate at the present time is 100.2 cases per 1,000,000. The United States is a frightening 377.1 cases per 1,000,000. In Canada, according to current data projections, the incidence of AIDS rate at least doubles every eighteen months.
• A number of patents disclose syringes or the like having needle protecting features. In spite of this there are no syringes which allow withdrawal and safe entrapment of needles currently on the market. This suggests difficulties with manufacture of prior patent designs. The syringe which is the subject of this patent application is manufacturable and commercially viable. In addition, after proper medical use the syringe cannot be reused and any toxic substances or infections contained within the barrel are not accessible without physical breakage of the syringe. U.S. Pat. No. 4,592,744, Jagger et al., Jun. 3, 1986, illustrates a disposable medical needle apparatus with a self-sheathing safety needle assembly. The self-sheathing safety needle has a case with a small closed end and a large open end. A needle assembly is located within the case with the needle projecting through the small closed end. A hub is connected to the needle assembly inside the case. The connector on the hub cooperates with a receiver on the small end to hold the needle assembly in the case. A flange on the hub cooperates with an inward projection in the case based from the small end to prevent movement of the needle out of the case when the needle is withdrawn from the opening in the small end. The nozzle of a syringe pushed into the hub withdraws the needle when the syringe is withdrawn. A rubber stopper on a vacuum tube withdraws the needle after the rubber stopper turns the flange to release the connector from the receiver.
• U.S. Pat. No. 4,804,370, granted Feb. 14, 1989, Haber et al., discloses a disposable disease control syringe which reduces the frequency of accidental needle strikes to health care workers and prevents health-threatening reuse of the needle cannula by drug abusers. The syringe includes a cylinder having an open proximal end, a substantially closed distal end, and a retractable needle projecting through the distal end. A piston assembly having a detachable stem and a needle capturing receptacle moves axially and distally through the syringe cylinder to expulse fluid medication and to selectively engage the needle at the most distal aspect of the cylinder. The piston assembly is then withdrawn proximally through the cylinder, whereby to relocate the needle from the distal end to the proximal cylinder end. The needle capturing receptacle is locked at the proximal end of the syringe cylinder with the needle cannula retracted within and completely shielded by the cylinder. The stem is then detached from the piston assembly and discarded, thereby creating a disposal cartridge with the needle cannula rendered permanently irretrievable therewithin. Alternatively, the piston assembly can be driven distally through the cylinder for correspondingly moving the needle into contact with a puncture resistant shield located at the distal end of the cylinder, whereby the needle is axially collapsed and destroyed within the cylinder.
• U.S. Pat. Nos. 4,542,749, Caselgrandi et al., and 3,306,290, Weltman, disclose syringes with protected needle designs.
• U.S. Pat. No. 4,631,057, Mitchell, discloses a syringe which has on the body of the syringe a needle guard which can be moved from a position which shields the needle, to a retracted position which exposes the needle. U.S. Pat. No. 4,425,120, Sampson, granted Jan. 10, 1984, also discloses a shielded hypodermic syringe with a needle guard mounted on the barrel which may be extended or retracted to protect or expose the needle. U.S. Pat. No. 4,573,976, Sampson et al., also discloses a shielded needle syringe comprising a needle guard which can be retracted or extended relative to the body of the syringe, means being provided for releasably retaining the guard in the retracted position. U.S. Pat. No. 3,884,230, Wulff, granted May 20, 1975, discloses a flexible needle guard and device for a hypodermic syringe. This design appears to be directed mainly to avoiding breakage of the needle when the syringe is being used.
• U.S. Pat. No. 4,258,713, Wardlaw, discloses an automatic disposable hypodermic syringe which has means for driving the hypodermic needle from a retracted position within the housing of the syringe to an injecting position whereby a portion of the needle protrudes from the housing. This device does not disclose a feature whereby the needle can be protected or retracted after use. U.S. Pat. No. 4,085,737 discloses a blood sampling syringe which includes an apparatus for protecting the open end of the needle of the syringe. The device is intended for minimizing risk of contamination of the needle tip after a blood sample has been taken. U.S. Pat. No. 4,260,543, Blum, granted May 12, 1981, discloses a hypodermic needle protection means which is designed so that the needle can be slidably moved to the interior of the needle support means upon application of pressure.
• U.S. Pat. No. 4,266,544, Wardlaw, granted May 12, 1981, discloses an improved disposable syringe wherein retracting means movably mounted on the housing of the syringe is adapted to pull the needle from its projecting position to a safe position whereby the needle is covered by a portion of the syringe. U.S. Pat. No. 4,139,009, Alvarez, discloses a hypodermic needle assembly with a retractable needle cover, the needle cover comprising a plurality of elastically resilient arms extending between a hub portion and a slide member, the arms acting as a restoring force for urging the slide member back over the needle forward portion when the syringe is withdrawn from contact with the skin of a patient.
• U.S. Pat. No. 4,774,964 discloses a device which is designed to withdraw blood from a patient. It is not a syringe per se. It is not used for injecting fluids into a patient. However, the device has the capacity to withdraw the needle into the barrel housing.
SUMMARY OF THE INVENTION
• This invention relates to a safety disposable syringe. More particularly, this invention pertains to a syringe which after being used by a health care person to inject medication or fluid into a patient or withdraw fluids from a patient, can be transformed by that person to withdraw the needle into the barrel of the syringe for disposal purposes, thereby eliminating the occurrence of needle sticking injuries among such health care persons. This syringe can also be used in industrial processes for sampling or adding substances which may be toxic. After such function, the needle is withdrawn into the barrel to prevent contamination at any further point in the process or during disposal. The syringe and retractable needle feature is adapted to be used with a variety of interchangeable needles of different diameter and length utilizing a universal Luer or Luer lock coupling mechanism.
• The invention pertains to a syringe comprising: (2) a hollow elongated barrel means; (b) penetration means which is adapted to removably engage with an end of the barrel means; (c) plunger means adapted to fit within and move axially in the hollow barrel means; the plunger means causing a pumping action within the interior of the barrel means between the plunger means and the end of the barrel means when the plunger means is pushed into the interior of the barrel means in the direction of the end of the barrel means; and (d) engaging means at the end of the plunger means proximate to the penetration means, the engaging means being adapted to engage the penetration means when the plunger means is fully inserted into the interior the barrel means in the direction of the end of the barrel means and cause the penetrating means to part from the barrel means and to be withdrawn into the interior of the barrel when the plunger means is withdrawn away from the end of the barrel means.
• In the syringe, the penetrating means can be a hollow needle which is pointed at one end thereof, and at the end opposite to the pointed end is formed to mate with the penetration means engaging end of the barrel means. An abutting means can be positioned within the interior of the barrel means and permits the plunger to be instead into the interior of the barrel means through one end but deters the plunger means from being withdrawn from the interior of the barrel means. Alternatively, the barrel means may have two abutting means in the interior of the barrel means, the two abutting means being adapted to trap the plunger means between them when the plunger means is partially withdrawn from the barrel means.
• In the syringe as defined, the engaging means may be a hook. The needle engaging means may be a female and male thread combination which is engaged by rotating the plunger relative to the barrel and penetrating means. Alternatively, the engaging means may be a cam-lack combination, the cam on the base of the needle penetrating means engaging with a receiving groove formed in the needle proximate end of the plunger, the cam-lock means engaging by rotating the plunger relative to the barrel.
• In another version of the syringe, the end of the plunger proximate the penetrating means can be formed with a snap-over attachment, and the end of the penetrating means proximate the plunger can be formed with a projection which is adapted to receive and be secured by the snap-over attachment.
• In a further embodiment of the syringe, the penetration means at the end proximate the plunger may be bent radially, and mate with a groove formed in the end of the plunger proximate to the bent end of the penetration means, the bent end of the penetration means and the groove in the plunger being engaged by rotating the plunger relative to the barrel of the syringe.
• The needle engaging means in the syringe can be a dual female thread combination, the dual threads being formed in opposite ends of the engaging means, and a male thread means being formed on the exterior of the engaging means outside one of the female threads, the exterior male thread means being of opposite thread rotation to the dual female thread means. The end of the needle proximate to the engaging means can have a male thread removably engageable with the proximate female thread of the engaging means. The plunger proximate to the engaging means can have a male thread engageable with the female thread of the engaging means opposite to the female thread engaging the male thread of the needle means.
• The invention also relates to an adapter for a syringe having a piston and a needle base fitting in the end of the syringe comprising: (a) a protrusion formed at one end of the adapter for fitting inside the hollow of a base affixed to a syringe needle; (b) releasable engagement means formed in the exterior of the adapter and being adapted to releasably engage with the interior of the needle receiving end of a syringe barrel; and (c) an engagement means formed in the end of the adapter opposite the protrusion, said engagement means being adapted to engage with the piston end of a syringe plunger.
• The piston engaging means of the adapter can be a spiral thread and the releasable engagement means can be a male thread. The penetration means of the syringe can be releasably engaged with the end of the barrel means by means of an adapter, and the adapter means can be adapted to engage with the engaging means at the end of the plunger means proximate to the penetration means by rotating the plunger means. The adapter means can be releasably connected to the end of the barrel means by a female-male thread combination, and the means of the adapter means adapted to engage the engaging means of the plunger means can be a spiral thread combination with locking means.
• The penetration means of the syringe can be a needle which is fitted with a Luer lock, the Luer lack being engaged with the adapter means. The needle-Luer lock combination and the adapter can be disengaged from the end of the barrel means by latch means which engages with the adapter when the plunger means is pushed to the needle end of the barrel and rotated to minimally withdraw and activate the engagement means.
• The adapter can protrude partially from the penetration means end of the hollow barrel means and can have a thread direction which is the same as or opposite to the thread direction of the barrel means engaging the penetration means. The adapter can be designed to protrude partially from the penetration end of a syringe barrel.
• In a further embodiment of the syringe the plunger is hollow and is a circular cylinder in cross section with a fastening means such as threads at the finger press end of the plunger. The plunger additionally includes a narrowed weakened break point whereby the hollow cylindrical portion of the plunger upon being withdrawn from the barrel may be broken away and fastened to the opposite end of the barrel whether or not the needle assembly has been withdrawn into the interior. Such construction allows for redundant manners of sheathing the needle assembly through the use of a needle guard or the cylindrical portion of the plunger. Both include threaded ends of the same size for attachment to the barrel and are relatively larger and more safely used than prior devices. Some additional features improve syringe function, for example, by enhancing the readability of calibration markings and thus improving the accuracy of the syringe.
• In a still further embodiment of the invention, the needle guard and the hollow cylindrical portion of the plunger are the same element. That is to say, the circular cylinder portion of the plunger includes at a narrowed intermediate point a reusable connection means in lieu of a break point. Such construction allows this portion of the plunger to be disconnected from the needle end portion of the plunger and used as a needle guard. Subsequently, this portion may be removed from the end of the barrel and reconnected to the needle end portion of the plunger. Moreover, such construction allows the interior of the syringe body to be sealed at both ends when the needle end portion of the plunger is withdrawn and the hollow cylindrical portion is in place on the barrel as a needle guard.
• Additional features found in the further exemplary embodiments are the use of colored material for the plunger, which due to its close proximity to the inner surface of the barrel provides a less distorted or clearer background for viewing the barrel calibration markings. Still further, the inclusion of a radially linear surface on the interior far end of the plunger bung, as well as using bung material of the same color as the plunger, presents a single flat interface which dramatically improves the visualization of the calibration markings and the alignment of the end of the plunger with such markings. More accurate filling and delivery of contents is then possible.
• Still further beneficial features of the disclosed exemplary embodiments include the use of annular ridges on the interior of the barrel and/or on the exterior of the plunger whereby the sealing ridges in combination with a needle guard attached to the opposite end of the syringe maintains sterile conditions in the syringe interior prior to use and after use seals bacteria or other material within the body of the syringe.
• Additional features to be found in the exemplary embodiments include a cup-like annular lip or resilient pronged projections on the plunger adjacent the portion at the break point which are used in combination with the interior ridges of the barrel at the finger press end to deter the needle assembly from being completely withdrawn from the interior of the barrel means. Such elements also retain the needle assembly at the finger press end of the barrel. As an additional feature of the exemplary embodiments, the needle assembly includes an adapter-plunger connection which is designed to allow unidirectional torque only so as to prevent re-attachment of the adapter to the barrel means without the use of a special tool. Thus, subsequent use of the needle once the adapter and barrel have separated is prevented in the absence of special tools or extraordinary measures.
• A further feature of the present invention resides in the provision of a venting structure in the adapter for venting air from the interior of the barrel once the barrel has been substantially filled with fluid to be injected and prior to injection. As well know, it is important that air be expelled entirely from the barrel so that air may not be injected with the fluid. In certain embodiments hereof, the hub or adapter, which releasably secures the needle to the distal end of the barrel and is adapted to be withdrawn with the needle from the distal end of the barrel into the interior of the barrel, has a connective structure which enables the plunger to grasp the adapter and withdraw the adapter and needle into the interior of the barrel. This connective structure protrudes toward the interior of the barrel, forming an annular space between it and the side walls of the barrel at the barrel's distal end. When the axially extending fluid passage passes entirely through the adapter opening into the interior of the barrel at a location spaced from the distal end of the barrel, there is the danger that air can be trapped in such annular space notwithstanding movement of the plunger toward the distal end to vent the air. That is, the fluid in the barrel may occlude the central passage, and prevent the air trapped in the annular space from venting.
• Therefore, in accordance with another aspect of the present invention the adapter is provided with one or more vent passages which open into the annular space at the most superior portion of the hollow barrel when the syringe is oriented substantially vertically with the needle uppermost. Consequently, after the fluid has been withdrawn into the interior of the barrel and the syringe oriented vertically needle end up, air is expelled through the vent passage into the central passage by moving the plunger toward the distal end of the barrel. The central passage may extend wholly through the adapter whereby the vent passage forms one or more branch passages of the central passage. Alternatively, the central passage may terminate within the adapter with more vent passages serving not only as air vents but passages for flowing the fluid through the needle during injection. To ensure that the vent passage(s) opens at the superior position in the interior of the barrel, the face of the radially enlarged portion of the adapter facing oppositely of the distal end of the barrel may be tapered radially inwardly toward the distal end of the barrel. Additionally, radial grooves may extend in the tapered adapter face and constitute continuations of the vent passages. Further, one or more annular grooves may be disposed in the tapered adapter face in communication with the radial grooves and vent passages, all to ensure venting of air from the syringe prior to use.
• A further desirable feature of a syringe is that it may be packaged and sterilized in bulk and not necessarily in individual packages. However, this leaves open the possibility of tampering or inadvertent disruption of seals and contamination. It is important, therefore, that the syringe hereof embody tamperproof features. To that end, in one embodiment hereof, tamperproofing can be accomplished by applying a strip of paper tape having adhesive along one side along the side of the syringe covering both the junctures of the needle guard and body of the syringe and the proximal end of the barrel and plunger. Thus, if the tape has been broken or is twisted or otherwise removed from the syringe, it would be evident that the seals at the opposite ends of the syringe have possibly been disrupted. Similarly, in another embodiment hereof, a tight shrink-wrap of plastic material may be provided about these junctures. Again, removal of the shrink-wrapped plastic material or a twisting or severing thereof would indicate a possible disruption of or tampering with the seals. In a further form of the invention, the syringe may be dipped into a plastic material in liquid form whereby a thin-film coating is applied to and solidified about the entire outer surface of the syringe, including the needle guard and projecting portion of the plunger. Consequently, sterility may be maintained, provided the thin-film plastic coating is not broken, while at the same time, disruption of or tampering with the seals at the aforementioned junctures is readily evident. The tamperproof seals may also be provided with sterilizing radiation sensitive material to evidence that the syringe has been sterilized and that the syringe remains sealed.
• In a preferred embodiment according to the present invention, there is provided a syringe comprising (a) a hollow, axially elongated barrel, (b) an adapter carried by the barrel adjacent a distal end thereof and removable therefrom in response to rotation relative to the barrel, the adapter carrying a needle and providing fluid communication with the interior of the hollow barrel, (c) a plunger axially movable in the barrel between first and second positions relative to the barrel, (d) adapter engagement structure disposed at the distal end of the plunger and engageable with a mating connection engagement structure on the adapter, the structures having respective drive and connective engagement surfaces, the drive surfaces being engageable with one another when the plunger lies in the first position relative to the barrel and jointly movable to enable rotation of the adapter relative to the barrel in response to relative rotation of the plunger and barrel to cause the adapter to part from the distal end of the barrel, the connective surfaces being engageable with one another to connect the plunger and adapter one with the other and enable the adapter, when parted from the end of the barrel in response to joint rotation of the adapter and the plunger relative to the barrel, to be withdrawn with the needle into the interior of the barrel in response to joint axial movement of the plunger and the adapter in a direction away from the distal end of the barrel and (e) a cap carried by the barrel and movable between a position closing the distal end of the barrel and a position avoiding interference with the distal end of the barrel.
DRAWINGS
• In the drawings which illustrate specific embodiments of the invention, but which should not be construed as restricting the spirit or scope of the invention in any way:
• FIG. 1aillustrates a side elevation view of the needle and hub components of a first embodiment of the syringe;
• FIG. 1billustrates a side elevation view of the barrel of a first embodiment of the syringe;
• FIG. 1cillustrates a side elevation view of the plunger, bung and hook of a first embodiment of the syringe;
• FIG. 1dillustrates an end elevation view of the hook;
• FIG. 2 illustrates a side elevation partial-section view of a first embodiment of the syringe assembly with the needle and hub secured to an end of the barrel, and the plunger and its bung and hook partially inserted into the interior of the barrel, prior to use of the syringe;
• FIG. 3 illustrates a side elevation partial-section view of a first embodiment of the syringe assembly with the plunger and its bung and hook fully inserted into the interior of the barrel so that the hook extends into the interior of the hub;
• FIG. 4 illustrates a side elevation partial-section view of a first embodiment of the syringe with the plunger, bung, hook and needle fully withdrawn into the interior of the barrel and the distal end of the plunger broken-off from the bung end of the plunger;
• FIG. 5 illustrates a side elevation partial section view of an alternative embodiment of the syringe which has a double screw action needle and hub engagement mechanism and the end of the plunger away from the needle and hub engagement mechanism has therein a cavity which can fit over the opening in the end of the plunger after the needle and hub are withdrawn into the interior of the barrel;
• FIG. 6 illustrates a detail view of the double screw action needle and hub engagement mechanism;
• FIG. 7 illustrates a side elevation partial section view of the needle and hub withdrawn into the interior of the barrel and the broken away part of the plunger placed over the opening in the head end of the barrel.
• FIG. 8 illustrates a side elevation partial-section view of a second embodiment of the syringe with a screw-lock plunger-needle hub connection;
• FIG. 9 illustrates a detailed side elevation partial-section view taken along section A-A ofFIG. 11 of a first design of a plunger with a right-hand or left-hand cam-lock rotation to secure the plunger to the needle hub for withdrawing the needle into the barrel of the syringe;
• FIG. 10 illustrates a detailed side elevation partial-section view taken along section A-A ofFIG. 11 of a second design of a plunger with a right-hand or left-hand cam-lock rotation to secure the plunger to the needle hub and a second right-hand or left-hand rotation locking means which provides a double locking action between the plunger and needle hub;
• FIG. 11 illustrates an end elevational view of the needle end of the syringe illustrated inFIG. 8;
• FIG. 12 is a section view taken along section line B-B ofFIG. 9 showing the syringe barrel handle and syringe plunger handle at a 45″ angle to one another to activate the right-hand rotation cam locking action;
• FIG. 13 illustrates a detailed side elevation partial-section view of side scoring on a plunger of a syringe with an oval flange cam lock;
• FIG. 14, which appears on the same sheet asFIG. 11, illustrates a detailed end elevation view of the cam lock mechanism of the embodiment of the syringe illustrated inFIG. 9;
• FIG. 15 illustrates a top elevation partial-section view of a plunger with a snap-on socket type needle hub connection;
• FIG. 16 illustrates a side elevation partial-section view of a plunger with a snap-on socket type needle hub connection;
• FIG. 17 illustrates a top elevation partial-section view of a plunger with a snap-on socket type needle hub connection combined with a right-hand rotation option;
• FIG. 18 illustrates a section view taken along section line A-A ofFIG. 16;
• FIG. 19 illustrates a side elevation partial-section view of a bent needle embodiment of a needle hub connection;
• FIG. 20 illustrates a top elevation partial-section view of a bent needle embodiment of a needle hub connection;
• FIG. 21 illustrates a side elevation partial-section view of a bent needle embodiment of a needle hub connection coupled with a right-hand rotation option;
• FIG. 22 illustrates a detailed end view of the diagonal slot in the end of the piston-plunger with the bent needle end fitted in the slot;
• FIG. 23 illustrates a detailed end view of the diagonal slot in the end of the piston-plunger rotated in the slot to grip the bent end of the needle;
• FIG. 24 illustrates a side elevation partial-section view of an embodiment of the syringe wherein the needle and hub are rotatably detachable from the barrel and the plunger threadedly engages the interior of the hub;
• FIG. 25aillustrates a side elevation partial-section view of the syringe with the needle and hub drawn within the interior of the barrel and the remote end of the plunger that is broken away, formed with a hollow threaded cap-like opening;
• FIG. 25billustrates a side elevation partial-section view of the syringe with the broken away plunger portion threadedly engaged with the male threaded end of the hub at the top of the barrel;
• FIGS. 25cand25dillustrate sequential side elevation views of an alternative design of syringe where the part of the plunger adjacent the break away weak point is threaded and is screwed into the opening in the end of the barrel vacated by the needle and hub when pulled into the barrel;
• FIG. 26 illustrates a side elevation partial-section view of an embodiment of the syringe wherein the piston is adapted with a latch which snaps into place in an adapter after the piston is fully depressed and rotated;
• FIG. 27 illustrates a side elevation partial section view of an adapter which mates with the needle platform;
• FIG. 28 illustrates a side elevation section view taken along section line C-C ofFIG. 2g;
• FIG. 29 illustrates an end view of the latch mechanism of the piston depicted inFIG. 26;
• FIG. 30 illustrates a side elevation view of an alternative design of adapter;
• FIG. 31 illustrates a side elevation partial section view of the alternative design of adapter;
• FIG. 32 illustrates a side elevation partial section view of an embodiment of the syringe wherein an adapter is mounted allowing Luer locked needles to be used and interchanged but permitting subsequent withdrawal of a used needle and adapter into the barrel;
• FIG. 33 illustrates a perspective view partially in phantom of a still further embodiment of a syringe, a needle guard and the threaded connection therebetween;
• FIG. 34 shows a side elevation view partially in section of the syringe embodiment ofFIG. 33;
• FIG. 35 illustrates a different side elevation view of the embodiment ofFIG. 33 in partial section view and with the needle guard removed;
• FIG. 36 illustrates a manner in which the plunger may be rotated with respect to the barrel in order to disconnect the needle assembly from the barrel for withdrawal of the assembly into the barrel;
• FIG. 37 is a side sectional view similar to that illustrated inFIG. 34 but with the needle assembly unfastened from the distal end of the barrel and with the assembly withdrawn into the barrel;
• FIG. 38 is a side sectional view similar to that illustrated inFIG. 37 but with the hollow cylindrical portion of the plunger broken away at the break point;
• FIG. 39 is a side elevational view partially in section with the hollow cylindrical plunger portion fastened to the distal end of the barrel after the cylindrical plunger portion has been broken away at the break point;
• FIG. 40 is a perspective view partially in section of the adapter and the distal end of the plunger illustrating the mating relationship of the noted elements;
• FIG. 41 is an axial view illustrating a pair of resilient prongs used to engage a groove at the finger press distal end of the barrel for retaining the needle assembly in the retracted position in the barrel;
• FIG. 42 is a partial side view of the pronged latching device ofFIG. 41;
• FIG. 43 is a side elevational view partially in section of a still further exemplary and presently preferred embodiment of the invention;
• FIG. 44 illustrates a section view of a portion of the plunger taken along section line44-44 ofFIG. 43;
• FIG. 45 is a detailed partial side elevation view of a portion of the plunger including the narrowed portion of the plunger which contains the break point as illustrated inFIG. 43;
• FIG. 46 is an enlarged sectional view illustrating a portion of the radially linear interface between the adapter and the plunger bung;
• FIG. 47 is an enlarged partial sectional view of ridges and an intervening groove on the inside surface of the barrel at the distal end and a corresponding annular ridge on the exterior surface of the hallow portion of the plunger which cooperates with the annular barrel ridges for locking and sealing purposes;
• FIG. 48 is a side elevational view partially in section of a still further embodiment of the invention which represents a modification of the embodiment ofFIG. 43;
• FIG. 49 is a side elevational view partially in section of the embodiment ofFIG. 48 illustrating the cylindrical plunger portion disconnected from the needle end portion of the plunger;
• FIG. 50 illustrates a partial end view of the plunger taken along line50-50;
• FIG. 51 is a perspective view of an adapter constructed in accordance with a still further embodiment of the present invention;
• FIG. 52 is an enlarged fragmentary cross-sectional view illustrating the adapter ofFIG. 51 disposed in the distal end of the barrel;
• FIG. 53 is a view similar toFIG. 52 illustrating a further form of the adapter;
• FIG. 54 is a perspective view of one form of a tamperproof syringe constructed in accordance with the present invention;
• FIG. 55 is an enlarged fragmentary cross-sectional view with parts broken out illustrating another form of a tamperproof syringe;
• FIG. 56 is an enlarged side elevational view with parts broken out and illustrating the opposite ends of a syringe having a tamperproof coating according to the present invention;
• FIG. 57 is a side elevational view of a syringe with the barrel end capped prior to use:
• FIGS. 58 and 59 are enlarged side elevational views of two additional embodiments of caps for capping the end of the syringe barrel;
• FIG. 59A is an enlarged fragmentary elevational view illustrating a cap with a hinge connecting the cap and the syringe barrel to one another;
• FIGS. 60-62 are side elevational views schematically illustrating the series of steps for re-applying the cap illustrated inFIG. 58 to the barrel end of the syringe after use of the syringe; and
• FIGS. 63 and 64 are side elevational views of a further form of syringe hereof and illustrating its manner of use.
• FIGS. 65-68 are fragmentary cross-sectional views of a still further embodiment of syringe hereof wherein the plunger is permanently locked to the adapter upon axial displacement of the plunger into final seated position relative to the adapter;
• FIGS. 70 and 71 are enlarged views similar to the embodiments ofFIGS. 65-69, illustrating a still further embodiment for permanently locking the plunger and adapter to one another;
• FIG. 72 is a view similar toFIG. 70 illustrating a still further embodiment of the syringe hereof;
• FIG. 73 is a schematic illustration of the coupling between the proximal end of the plunger and the distal end of the barrel once the adapter and needle have been withdrawn into the barrel;
• FIGS. 74 and 75 are cross-sectional views of the embodiment ofFIGS. 65-69 taken generally about on lines74-74 and75-75 inFIG. 65;
• FIGS. 76 and 77 are views similar toFIGS. 74 and 75 taken generally about on lines76-76 and77-77 inFIG. 69;
• FIG. 78 is a fragmentary cross-sectional view illustrating an adapter and plunger end combination in accordance with a further form of the present invention; and
• FIG. 79 is a view similar toFIG. 78 illustrating the adapter and plunger end in engagement with one another in the end of a syringe barrel.
DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION
• Most disposable syringes can be used with a variety of interchangeable needles with different diameter and length. The needles are connected by what is known as a Luer connector, which may be of two types. One is a simple conical device which accepts the needle base. This version is often described as a Luer tip. To detach-the needle, it is simply pulled off. The other connector type is often described as a Luer lock. The Luer lock has a simple screw thread locking mechanism that permits the base of the needle to be screwed onto the syringe so that it cannot be pulled off without unscrewing. In this disclosure, the universal coupling mechanism connecting the needle to the syringe will be referred to as a Luer lock version of the Luer connector unless otherwise indicated. It should be recognized that the claims to the invention relate to both the plain Luer tip and the Luer lock mechanisms. The interchangeability capability of a Luer lock allows for the most appropriate needle to be used for syringe filling and patient injection. In many cases, to save time, a different larger needle is used to fill the syringe with fluid prior to injection. A needle of fine caliber to minimize pain to the patient, and tissue damage, is often used for intramuscular or subcutaneous injection. In addition, if the same needle is used to puncture a vial in order to fill the syringe with medication, there is a potential for contamination of that needle from the vial, if the vial stopper carries a contaminant. Under most circumstances, this would not pose a significant risk. However, if the patient has reduced immunity to infection, the ability to change to an entirely new sterile needle for patient injection may become important.
• Although the prior art describes syringes which can protect the needle by a variety of means, including those which involve withdrawing the needle into the interior of the barrel of the syringe, such syringes do not allow for interchangeability of the needle or for the universal Luer lock coupling mechanism which is an important feature of the syringe. Most commercially available syringes employ a Luer lock. Since the subject invention is adapted for use with a Luer lock, it can directly replace syringes currently in use and requires no change in technique or procedure until after the syringe has been used. In addition, most currently produced needles can be used in the usual manner on this syringe.
• After use, once the needle has been withdrawn into the barrel, the syringe plunger can be snapped off. It is designed so that it can be screwed onto the front of the syringe and thereby prevent any possibility of the needle within the barrel protruding through the front of the syringe again. This is an important factor for a health care worker using the syringe and also for any health care workers subsequently handling garbage which might contain a contaminated syringe.
• This invention pertains to a syringe which, after being used by a health care worker or hazardous industries worker, or the like, to inject medication or fluid into a patient, or withdraw fluid from a patient, or in sampling toxic material, for example, in an industrial process, can be transformed by the worker to withdraw the needle into the barrel of the syringe for disposal purposes, thereby eliminating potentially harmful needle stick injuries among such workers. In industrial applications, the storage of a contaminated needle is similarly effected within the barrel to prevent further contamination of the environment or process.
• With any one of the various embodiments of the basic syringe design, the needle is retracted by the user into the interior of the body of the syringe immediately after it is withdrawn, or during its withdrawal, from the patient's body tissue, or after exposure to hazardous situations. Thus, the needle is not exposed for accidental contact at any time after the needle has contacted the potentially hazardous patient's body fluids, or other hazardous materials. This retraction feature eliminates the possibility of potentially dangerous needle stick injuries occurring with contaminated needles.
• The safety syringe of the invention is simple to operate and is only slightly more expensive to manufacture than presently used syringes. Another advantage is that the syringe design closely resembles currently used syringes and thus there should be no difficulty in obtaining good acceptance among workers such as medical institutional workers since: the syringe is hermetically sealed before and after use; redundancy of mechanisms allows safe disposal and protection from needle stick injuries and accuracy of reading calibration markings for filling of syringe is more precise.
• Moreover, the operation of the subject syringe is easy to teach to such workers and requires no unusual skills or manual dexterity.
• Syringes that are in current commercial use normally consist of four components, a needle cap which is removed prior to use, a hollow needle which is mounted on a hub with a Luer lock, a barrel to which the hub is attached, and a plunger with a bung (piston) at the head end of the plunger. The plunger is inserted within the barrel head end first and can be pushed into the interior of the barrel in order to pump fluid contained in the barrel out through the interior of the hollow needle. The subject invention, in various embodiments, includes several basic modifications which do not dramatically change the appearance of the conventional syringe.
• Referring to the drawings,FIGS. 1a,1band1cillustrate the three basic components which make up a first embodiment of the novel needle retractable syringe.FIG. 1aillustrates in side elevation partial section view the construction and interaction of theneedle2 andcup4 which fits detachably within the interior ofhub6 of the syringe.Hub6 has a female thread in the base of its interior.FIG. 1billustrates in side elevation partial section view the construction and interaction of thebarrel8, the partially closed threadedhub receiving end10, which is located at the top of thebarrel8, and thebarrel base12 which is formed at the bottom of thebarrel8. A circular rim-like catch14 is formed in the interior of thebarrel8 immediately above thebarrel base12 and provides a stop to deter full withdrawal of theplunger16 from the interior of thebarrel8. Alternatively the needle may during manufacture be affixed integrally to the syringe base and be removable only during retraction into the barrel after the syringe has been used.
• FIG. 1cillustrates the construction of theplunger16, which includes a bung (piston)18 which fits snugly against the interior of thebarrel8 and serves to force the liquid contents of the interior of the hollow barrel8 (usually medication) out the interior of thehollow needle2, and in a common situation into the body of a patient, when theplunger16 is manually pushed into the interior of thebarrel8. A thumb orfinger press20 is formed at the base of theplunger16, while thebase22 of the bung18 serves to align theplunger16 within the interior of thebarrel8, and deter full withdrawal of theplunger16 from thebarrel8 by abuttingcatch14. Affixed to the top central area of the bung18 is a fivetine metal hook24.
• FIGS. 2, 3 and4 illustrate in sequential side elevation partial-section views, the syringe in assembled state, with the components in various positions.FIG. 2 illustrates the syringe assembly when it is charged with a fluid such as fluid medication, or the like, ready for use. The fluid is contained in the volume space immediately above thebung18 and below the threadedhub receiving end10. When theplunger16 is fully pushed by the thumb orfinger press20 upwardly into the interior of thebarrel8, the fluid contents of the syringe are extruded byplunger16 andbung18 through the hollow interior ofneedle2 and out the pointed end. At the same time, one or more of the tines of thehook24 engages with the interior ofcup4 as illustrated inFIG. 3. Subsequently, as illustrated inFIG. 4, when theplunger16 is almost fully withdrawn from the interior of barrel B, thehook24 pulls thecup4, and the attachedneedle2, downwardly through the interior ofhub6, and into the interior of barrel S. Thus all of theneedle2 is retracted into the interior of thebarrel8. If desired, the portion of theplunger16 which extends beyondbase12 can be broken off at the weakened section, as illustrated inFIG. 4, and the two components disposed of in smaller pieces.
• As seen inFIG. 1a, the metal of the needle is extended to form a bell shapedcup4, which fits within the interior of and is affixed to theplastic hub6. By using this construction, in this embodiment, the likelihood that a break will occur between theneedle2 and thecup4 is minimized. Theneedle2 and thecup4 are formed in one piece, and since the metal is stronger than the plastic forming thehub6, a break between the metal and the plastic is encouraged.
• When theplunger16 is fully depressed into the interior of thebarrel8, the one or more of the tines ofhook24 engage the interior of thecup4, and then, when theplunger16 is withdrawn, thehook24 pulls on the interior of thecup4 and causes it to break away fromhub6. Once a full break has been made,needle2 andcup4 are drawn into the interior of thebarrel8 by further withdrawing theplunger16.
• The syringe of the invention has a built-in safety feature in that theneedle2 can only be withdrawn into the interior of thebarrel8 up to the point that guide22 abuts thecatch14 located around the interior rim of the base of thebarrel8. Thus, unless considerable effort is exerted, it is not possible to pull theneedle2,cap4 andplunger16 completely through thebarrel8. Thecatch14 is designed so that when the components are assembled, it is easy to insert the bung18, with thehook24, and theguide22 through the interior of the one-way catch14, and into the interior of thebarrel8 but it is difficult to fully withdraw these components. Once theneedle2 is withdrawn into thebarrel8 byhook24, it is not supported laterally and tips to one side against thebarrel8, thereby making it virtually impossible to push theneedle2 back through thehub6. The tines ofhook24 are not necessarily of the same length, which encourages tipping of theneedle2 to one side. Breaking off the portion of theplunger16 that extends beyondbarrel base12 ensures that the usedneedle2 cannot be pushed back throughhub6, thereby exposing the sharp point of theneedle2 beyondhub6. Also, it is usually easier to dispose of two smaller shorter components than one elongated one.
• FIG. 5 illustrates a side elevation partial section view of a preferred embodiment of the syringe which has a double screw action needle andhub engagement mechanism80. The end of theplunger16 away from the needle andhub engagement mechanism80 has therein acavity82 which can fit over thecup84 and opening in the end of thebarrel8 after theneedle2 andhub6 are withdrawn into the interior of the barrel8 (seeFIG. 7).
• FIG. 6 illustrates a detail view of the double screw action needle andhub engagement mechanism80. Themechanism80 is constructed so that it has right handfemale threads86 of one size diameter in a cup-like opening at one side, a right handfemale thread88 of a narrower side diameter in a cup-like opening in the opposite side, and a left-hand male thread90 on the exterior of themechanism80 outside the interiorfemale thread88.
• Hub6 screws intofemale thread88 and the syringe is used in this configuration for injecting medication into a patient. However after use, to operate themechanism80, to enable the needle to be withdrawn into thebarrel8, the head end of the plunger and bung18 are screwed right handed into thefemale thread86. Once fully engaged, then further right hand action on left-handed thread90, unscrewsthread90. Theentire mechanism80 including theneedle2 can then be withdrawn into the interior of thebarrel8. The right hand and left hand threads can, of course, be reversed to operate in the reverse manner, if that is required.
• FIG. 7 illustrates a side elevation partial section view of theneedle2 andhub6 withdrawn into the interior of thebarrel8 and thecavity82 of the broken away part of theplunger16 placed over the opening andcup84 in the head end of thebarrel8.
• FIG. 8 illustrates a side elevation partial-section view of a second embodiment of the syringe which is constructed to have a screw-lock plunger-needle hub connection. As can be seen inFIG. 8, thebarrel8 has thesyringe plunger16 disposed therein. Theplunger16 carries at its frontal end (the left end as seen inFIG. 8) apiston26 which is constructed of a resilient material such as resilient rubber so that it snugly engages the inner cylindrical surface of thebarrel8. Thepiston26 is connected to theplunger16 by means of aplunger flange36. The frontal end of theplunger16 is constructed to have therein a cylindrical cavity which has afemale thread28 formed in the wall of the cavity. The base of thehub6 is constructed to have amale hub thread34, which is formed to match and engage thefemale thread28 formed in the opening in the front end of theplunger16.FIG. 8 also illustrates piston stop15 formed in the rear end of the interior of the barrel8 (the right side as seen inFIG. 8).Piston stop15 serves the same purpose ascatch14 as discussed in relation to FIGS.1 to4 above. Acap32 protects theneedle2 and fits over thehub6.Cap32, when engaged after theneedle2 is withdrawn prevents exposure of theneedle2 if it is accidentally pushed back through the opening at the forward end of the syringe.
• In use, theplunger16 andpiston26 are disposed withinbarrel8 as illustrated inFIG. 8. Thecap32 is removed and the pointed end of theneedle2 is inserted into the medication. At this time,female hub thread34 is not engaged inmale thread28. The fluid medication is drawn into the interior of thebarrel8 by suction action created by withdrawingpress20 andplunger16 from the interior orbarrel8, as is conventional. Once the desired quantity of medication has been drawn into the interior of thebarrel8, and air is eliminated, the sharp end of theneedle2 is inserted into an appropriate location on the patient. The medication that is held within the interior ofbarrel8 is injected through theinterior needle2 into the patient by asserting thumb or finger pressure onpress20. Once the medication has been injected into the patient, thepiston26 has moved to the position illustrated inFIG. 8. It is then necessary to initiate the action which is ultimately used to withdraw thehub6 and theneedle2 into the interior of thebarrel8. This is done by asserting a clockwise rotation onpress20, which engagesmale hub thread34 infemale thread28 in the end of plunger16 (assuming thatthreads28 and34 are right-hand threads).Hub6 andplunger16 are then intimately engaged bythreads34 and28 interacting with each other.Press20 can then be withdrawn to pull theplunger16 from the interior ofbarrel8. By this action, thehub6 andneedle2 are pulled into the interior ofbarrel8 until the rear end ofpiston26 comes to rest againstpiston stop point15. At this point, theplunger break point30 has been withdrawn exterior of thebarrel8, and consequentlyplunger16 can be broken into two parts at theplunger break point30. The two parts of the syringe can then be disposed of with complete safety since theneedle2, which might have been exposed to harmful virus, or the like, has been withdrawn into the interior ofbarrel8, while the part of thesyringe16 that has been broken away atbreak point30, has not been exposed to any medicine and can be discarded without danger. It will be recognized thatbreak point30 is an option which need not necessarily be built intoplunger16. Breaking the syringe into two parts permits easy disposal whereas one elongated syringe, with the plunger withdrawn might be difficult to dispose of in certain instances.
• FIG. 9 illustrates a detailed side elevation partial-section view taken along section line A-A ofFIG. 11 of a first design of apiston26 with a right-hand cam-lock rotation (rather than a thread configuration) to secure the forward end of thepiston26 to theneedle hub6 for withdrawing theneedle2 into the barrel of the syringe. The cam-lock option illustrated inFIG. 9 operates by asserting a right-hand rotation on thepress20, relative to thebarrel8. In this way, cam-lock ridge42, which is formed in the base ofhub6, rotates into helical engagement with cam-lock groove44. This combination replaces themale hub thread34 andfemale thread28 combination illustrated inFIG. 8, as discussed previously. Once the cam-lock ridge42 is engaged snugly within cam-lock groove44, theneedle2 andhub6 can be withdrawn into the interior of thebarrel8.
• FIG. 10 illustrates a detailed side elevation partial-section view of a second design of a plunger with a right-hand cam-lock rotation (similar to that illustrated inFIG. 9). However, the design shown inFIG. 10 also includes asecond hub rim38 which is formed in the base area ofhub6. The purpose of hub rim38 is to engageleft hand thread40, which is formed in the interior of thebarrel8, which houses thehub6. The alternative option illustrated inFIG. 10 includes the right-hand cam-lock ridge42, cam-lock groove44 combination, discussed in association withFIG. 9, but it has a second feature. A right-handmale hub rib38 is formed in the exterior ofhub6 forward of cam-lock ridge42. A matching right handfemale thread40 is formed in the interior of the forward end ofbarrel8, that is, the end which surroundshub6. To operate the double action embodiment illustrated inFIG. 10, cam-lock ridge42 is first engaged in cam-lock groove44 by clockwise (right hand).rotatingpress20 relative to barrel base12 (seeFIG. 8) and then, by means of a second right handed (counterclockwise) rotation, hub rim38 is engaged within femaleleft hand thread40. Theneedle2 andhub6 are then double engaged by two right hand twists and can then be withdrawn into the interior of thebarrel8. The double-action engagement mechanism ensures proper secure engagement of the plunger and hub.
• It should be recognized that the first and second options illustrated inFIGS. 9 and 10 respectively can be used in any of the alternative embodiments of the invention that are illustrated inFIGS. 11 through 23. It should also be recognized that the double-action locking mechanism illustrated inFIG. 10 can be right-right, left-left, right-left or left-right.
• FIG. 11 illustrates an end elevation view of the needle end of the syringe illustrated inFIG. 8, and clearly illustrates the eccentric construction of right-hand cam-lock ridge42.Ridge42 is constructed generally in the form of an oval, the opposite ends of the oval being adapted to engage in the right-hand grooves of the cam-lock groove44 (seeFIG. 9 or10).
• FIG. 12 is a section view taken along section line B-B ofFIG. 9 and illustrates thesyringe barrel base12 and thepress20 rotated clockwise 45′ relative to one another. This clockwise action engages cam-lock ridge42 in cam-lock groove44.
• FIG. 13 illustrates in detail a side elevation partial-section view of right-hand side scoring on the interior frontal opening a plunger of the syringe adapted for use with the oval flange cam-lock. As can be seen, by means of the helically angled right-hand groove44, the right-hand oval shapedridges42, when they become mated in the interior of the pair of cam-lock grooves44, rotate relative to one another in a helical fashion, thereby creating a secure fit.
• FIG. 14 illustrates a detailed end view of the cam-lock mechanism of the embodiment of the syringe illustrated inFIG. 9.Barrel8 and cam-lock ridge42 are shown in solid lines. The dotted lines represent the cam-lock groove44.
• FIG. 15 illustrates a top elevation partial-section view of aplunger16 which is equipped with an alternative design engaging mechanism, namely a snap-on socket-type needle hub connection.FIG. 16 illustrates a side elevation view of the snap-on socket type needle hub connection illustrated inFIG. 15. As can be seen in these two illustrations, the forward end of theplunger16 is constructed so that it has a snap-on”fastener46, which, when theplunger16 is pushed strongly (in a leftwardly direction as seen inFIG. 16) snaps over and embraces the longitudinal knob-like end48 that is formed in the base ofhub6. The snap-onfastener46 andknob48 engagement combination is an alternative embodiment which replaces the cam-lock ridge42 and cam-lock groove44 combination illustrated inFIGS. 9 through 14, as discussed previously. Unlike thethread combination28,34 (FIG. 8) and cam-lock combinations (FIGS.9 to14), no rotational action is required to engagefastener46 andknob48. Once snap-onfastener46 has been pushed over snap-overknob48, thehub6 andneedle2 can be withdrawn into the interior ofbarrel8 by pullingpress20 from thebarrel8.
• FIG. 17 illustrates the snap-on fastener46-snap-overknob48 embodiment discussed previously in relation toFIGS. 15 and 26, but includes the option a right-hand hub rim38 and a righthand option thread40 secondary engagement mechanism (as discussed in detail previously in association withFIG. 10).
• FIG. 18 illustrates a section view of the syringe taken along section line A-A ofFIG. 16. The rectangular construction of the snap-onfastener46, which fits over snap-overknob48, can be readily seen. Also visible inFIG. 18 are the plunger, flange36 (shown in dotted lines),barrel8,needle2, andbarrel base12. FIGS.15 to18 illustrate a cylindrical embodiment. It should be understood that alternative shapes such as hexagonal or octagonal can be used. The advantage would be that such a configuration would allow for rotary movement to be transferred to the needle assembly and allow it to be broken away by rotation rather than by simple traction.
• FIGS. 19 and 20 illustrate respectively side and top elevation partial-section views of a further alternative engaging mechanism, namely a bent needle hub engaging embodiment of the syringe.FIG. 19, which depicts the side elevation view, incorporates the first option (that is, withoutoptional hub rim38, andright hand thread40 combination).FIG. 19 shows how the base end of theneedle2 is bent at right angles to form an upwardly projectingend50. Theend50 fits into a slot andgroove52, which is formed in the forward end of theplunger16. By rotating theplunger16, andpiston26 about 90′ relative to end50, theend50 engages inslot52, thereby securely connecting the head end ofplunger16 withhub6 andneedle2. This engagement allows thehub6 andneedle2 to be withdrawn into the interior of thebarrel8, as described previously.FIG. 21 illustrates the bent needle embodiment that was discussed above in relation toFIGS. 19 and 20, but including the option of ahub rim38, andright hand thread40, formed in thehub6 to provide a double engagement mechanism. As mentioned previously, either option 1 or option 2 (FIG. 9 or10), can be utilized in all embodiments of the syringe as discussed.
• FIGS. 22 and 23 illustrate a detailed end view ofslot52 andneedle end50, theslot52 being formed in the head end of theplunger16. Thebent needle end50 is first inserted inslot52, as illustrated inFIG. 22, and then theend50 is rotated 90

  

  into a groove opening formed in the interior of theplunger16, thereby engaging the base end of theneedle2 with theplunger16.
• FIG. 24 illustrates a side-elevation partial-section view of an embodiment of the syringe wherein the needle and hub are rotatably detachable from the barrel and the plunger threadedly engages the interior of the hub. The base of theneedle2 is threadedly and removably engageable with thehub63 bythreads62. In turn thehub63 is threadedly and removably engageable with thebarrel8 bythread64. The head end of theplunger16 can engage with the interior of thehub63 byinterior threads65 and withdrawneedle2 andhub63 into the interior of thebarrel8. The interior of the
• • head end ofbarrel8 is shaped like an “M”. The angled ends deter theneedle2 from pushing back through the opening in the end of thebarrel8.
• FIG. 25aillustrates a side elevation partial-section view of the syringe with the needle and hub drawn within the interior of the barrel and the remote end of the plunger that is broken away, formed with a hollow threaded cap-like opening andFIG. 25billustrates a side-elevation partial-section view of the syringe With the broken away plunger portion threadedly engaged with the male threaded end of the hub at the top of the barrel.
• As shown inFIG. 25a, thehub6 can be formed so that it hasmale threads70 around its circumference. Correspondingly, a mating cavity with matingfemale thread72 can be formed in the thumb press end ofplunger16. If need be, the thumb press end ofplunger16 can be widened atlocation74 in order to accommodate the cavity with thefemale thread72.
• With this embodiment, when theplunger16 is broken away atbreak point30, it can be used to cover the open end ofsyringe8 by screwingfemale threads72 ontomale threads70 ofhub6. In this way, both ends of thebarrel8 are closed, and there is no way that the potentially contaminatedneedle2 can escape the interior of barrel B.
• Alternatively, once the plunger has been broken, the end distant from the thumb press and proximate to the fracture site can be fashioned to allow it to fit snugly or screw into the now open end of the barrel (from which the needle has now been withdrawn into the barrel). If required, a second fracture site (not shown) can be fashioned in the plunger. This permits the plunger to be broken off at either of the two fracture sites according to the performance of the user.
• FIGS. 25cand25dillustrate sequential side elevation views of an alternative design of syringe where the part of theplunger16 adjacent the breakawayweak point30 is threaded at78 and is screwed intofemale threads76 of the opening in the end of thebarrel8 vacated by theneedle2 and hub when pulled into thebarrel8.
• FIG. 26, illustrates a side elevation partial-section view of an embodiment of the syringe wherein the piston is adapted with a latch which snaps into place in an adapter (platform) after the piston is fully depressed and rotated clockwise. The embodiment illustrated in FIG.26 depicts theneedle2 embedded in aLuer lock100, associated with theconstricted end10 of syringe barrel B. Theplunger16 with afinger press20 at the remote end thereof is positioned insidebarrel8. Astop rib14 prevents theplunger16 from being totally withdrawn from the interior of thebarrel8.Bung18, which provides a tight fit with the interior ofbarrel8, is mounted on the end ofplunger16 oppositefinger press20.
• The operative needle engagement and detachment mechanism illustrated inFIG. 26 is a combination of anadapter102, which cooperates withLuer lock100, the combination fitting into thenarrow end10 ofbarrel8. The end ofplunger16 oppositefinger press20 has alatch mechanism104 formed insidebung18. A pair ofprongs106 are formed inlatch104 and engage intogrooves108 inadapter102 when theplunger16 is rotated in a clockwise direction. Once the pair ofprongs106 engage in therespective grooves108 of theadapter102, then theplunger16 is rotated further clockwise which then, because of theleft hand threads110 engaging the interior of thenarrow end10, causes the adapter, and the needle with theLuer lock100, to disengage from thenarrow end10. At this point, theneedle2,Luer lock100,adapter102, and bung18 can be withdrawn into the interior of thebarrel8 by pullingfinger press20 away from thenarrow end10 of the syringe.
• As can be recognized, theadapter102 is an important feature of this embodiment of the invention. The adapter enables astandard Luer lock100 to indirectly mate withlatch104 at the end ofplunger16. Moreover, theadapter110 is designed so that it accommodates different sides ofneedle2 andLuer lock100.
• FIG. 26 illustrates a narrow point in the plunger which assists in breaking the plunger in two. If required, or desirable, two or more additional narrow points can be included to permit breakage at alternative locations.
• FIG. 27 illustrates in side elevation partial section view a preferred embodiment of theadapter102.Nose112 is adapted to fit inside the hollow of astandard Luer lock100. Theleft hand thread110 is also shown inFIG. 27. Theadapter102 has opposite the nose112 a cup-like edge114 which is formed to receive the front end oflatch104. Formed inside the rim of cup114 is aprotrusion116 which has a pair of fast acting spiralmale threads118 formed thereon.Prong engaging grooves108 are also formed in the interior of theprotrusion116 at the point where theprotrusion116 joins with the cup114. The advantage of this adapter design is that with the fast actingspiral threads118 force alignment without jamming. Full axial movement is possible with no rotation forced by the alignment threads. Then after full depression of the plunger, rotation will disengage theadapter102 and allow theprongs106 to engage ingrooves108. Rapid engagement between theprongs106 ingrooves108 is achieved by minimal rotation of theplunger16. At that point, further clockwise rotation of theplunger16 by means offinger press20 causes thethreads110 ofadapter102 to disengage from the interiornarrow end10. Theneedle2 assembly can then be withdrawn into the interior ofbarrel8.
• FIG. 28 illustrates a section view taken along section lines C-C ofFIG. 29 and depicts a detailed view of the construction of thelatch104 and prongs106. In the embodiment illustrated inFIG. 28, thelatch104 has a pair ofalignment ridges120 formed in the interior oflatch104. Thesealignment ridges120 assist engagement of thelatch104 withadapter102.
• FIG. 30, which illustrates a side view of an alternative design ofadapter102, andFIG. 31, which illustrates a partial cut-away section view of the adapter depicted inFIG. 30, illustrate flared grooves129, which are adapted to receiveridges120 oflatch104. The flare assists in enabling theridges120 to be received intogrooves122. In this embodiment, the adapter does not have the fast acting non-jammingspiral threads118, depicted in the adapter design illustrated inFIG. 27.
• Theadapter102 has arim124 which is designed to engage with the rim126 of theLuer lock100 to hold the two snugly together.
• The embodiments of the invention depicted in FIGS.26 to31 have a number of advantages:
• • 1. The preferred embodiment allows for universal coupling with all Luer lock needle connections.
  • 2. Needle interchangeability during use of the syringe is possible, that is, different needles can be used for filling the vial and for injecting the patient.
  • 3. The needle platform (adapter) design allows for compatibility of the syringe with other custom design needles or any subsequent needle design, merely by altering the outer needle connection configuration platform.
  • 4. The syringe hub can be permanently closed after use of the syringe by screwing on the broken plunger stalk after withdrawal of the needle into the barrel.
  • 5. The novel coupling mechanism between the platform and the plunger allows full axial movement of the plunger without the possibility of an inadvertent locking. But deliberate rotational action permits locking of the coupling device and withdrawal of the platform (adapter) with the attached needle in the barrel.
• FIG. 32 illustrates a side elevation partial side section view of an embodiment of the invention related to that illustrated in FIGS.26 to30. The embodiment depicted inFIG. 32 shows anadapter130 which extends partially from the front end of thebarrel132. Astandard Luer lock134 is formed in the front end of thebarrel132. The Luer lock has a standardright hand thread135. Thebarrel132 has aleft hand thread137 to release theadapter130 for withdrawal inside thebarrel132, after the syringe is used. Aneedle hub136 carryingneedle140 fits on the tapered front end ofadapter130 and screws into the right hand thread of theLuer lock134. A givenclearance138 permits theneedle hub136 to be withdrawn into the interior of thebarrel132 after theadapter130,hub136, andneedle140 are unscrewed and withdrawn into thebarrel132 by rotation of the plunger and engagement of the plunger adapter connection mechanism. As described previously, a Luer tip may be a simple conical device which accepts the needle base. This design could also be used in this embodiment, thus eliminating the screw connection of theneedle hub136 and theLuer lock thread135.
• One advantage of the syringe design depicted inFIG. 32 is that theadapter130, allows for longer needles to be accommodated. Another advantage is that by reducing the minimum diameter of the platform needle combination, a thinner barrel can be manufactured. For a given capacity of syringe, this will allow the length of the syringe to be longer and therefore a longer needle to be accommodated within it. By placing the Luer lock threads in the barrel of the syringe rather than on the platform, the outer diameter of the platform needle combination is defined by the width of the needle hub and not by the supporting outer plastic Luer lock mechanism. It is therefore possible to ensure as long a barrel as possible for a given capacity. The standard 3 cc syringe represents a main portion of the syringe market. A standard 3 cc syringe is often used with a 1½ inch needle for intramuscular injection. Accordingly, the barrel of a 3 cc syringe should be at least 2½ inches long to accommodate the withdrawn needle, adapter and plunger connector all within the barrel. This is done by the design as shown inFIG. 32.
• The foregoing embodiments discuss various means of enabling the plunger to be connected securely to thehub100 of theneedle2 inFIG. 26, for example, to enable theplunger16, when withdrawn, to pull thehub6 andneedle2 into the interior of the barrel S. In some versions including the adapter, the adapter disengages if it (the plunger connector) is twisted in the wrong direction. This provides an over tightening safety feature. The adapter is released from the syringe if the correct rotation is used. It will be recognized that these are illustrative of specific embodiments and there are other possible ways to make a secure connection for the purpose of withdrawing the hub and needle into the interior of the barrel.
• FIG. 33 shows a perspective view partially in phantom of another embodiment of a safety syringe which includes aplunger154 within abarrel152. The syringe additionally includes aneedle hub156 carrying aneedle155 which may be covered by aneedle guard151 that is affixed to the barrel by way ofbarrel threads153 and the complementary threads of the guard.
• As more clearly seen in the side elevation partial sectional view inFIG. 34, the plunger includes a circular cylindrical portion154ahaving a threadedend portion154b, afinger press plate154cand an outerannular ridge154dfor providing a sealing engagement with groove152aofbarrel152. The plunger additionally includesportion154efor engaging theneedle adapter150 as well as theplunger bung157.
• Theplunger154 additionally includes a narrowedportion154fincluding a weakened break point154g, as well as a pair of resilient arms orprongs154h. The details of these elements will become more apparent from a review of the expanded detailed drawings ofFIGS. 41 and 42, for example.
• Returning to the syringe as illustrated inFIG. 34, it will be noted that once sterilized and assembled as illustrated with the needle guard in place forming a sealing engagement with the threaded barrel, as well as with the plunger in the position shown forming a sealing engagement betweenelements152aand154d, the interior of the structure is sealed at both ends, thus maintaining sterile conditions. As to forming and maintaining the above noted seals, it will be recognized that other forms of seals may be used. For example, although the exemplary embodiment illustrated inFIG. 34 includes a threaded connection between the needle guard and the end of the barrel, other forms of sealing arrangements involving friction fits or the use of annular ridges and complementary grooves, as well as other sealing connections as illustrated in previous embodiments, may also be used. In this regard, however, it will be noted that thethreads153 of the barrel are not only designed to accommodate a threaded connection withneedle guard151, but are also sized and designed to accommodate a threaded connection withcomplementary threads154bof the hollow plunger portion154aonce this plunger portion is broken away and connected to the end of the barrel, as illustrated inFIGS. 38 and 39. Accordingly, any change in the connection elements of151 and152, as previously suggested, would require a corresponding change in the manner of connectingelements152 and154a.
• Again returning to the embodiment as illustrated inFIG. 34, considered along with the enlarged element details illustrated inFIG. 40, it is evident thatadapter150 is connectable toplunger portion154eby way ofcomplementary surfaces150aand154i, as well assurfaces150dand154k. As may be seen from a consideration ofFIG. 40, all of these surfaces engage when the plunger is fully inserted and due to the slopes of the surfaces produces only a unidirectional torque on the adapter when the plunger is rotated in the proper direction. Plunger rotation in the opposite direction causessurfaces150dand154kto separate and the plunger to be partially withdrawn. In operation withdrawal of the plunger and the attachedbung157 away from theadapter150 is accomplished with relative ease since the adapter is securely attached to thebarrel152 by way ofcomplementary threads150band152b, as may be seen from a consideration ofFIGS. 35 and 37. Adding to the ease of separation of the adapter and plunger-bung is the relatively large slope of the thread surfaces150aand154iwhich offer little or no resistance to separation. Moreover, although theresilient ridge154jand groove150c(FIG. 40) offer some resistance to separation, the combination does not prevent such separation or require more than a reasonable force to “unsnap” the connection when the adapter is affixed to the barrel.Ridge154jmay be partially or wholly annular as one manner of decreasing or increasing resistance to separation.
• After use and with the adapter and plunger connected as illustrated inFIG. 34, the plunger may be rotated in the manner shown inFIG. 36 so as to disconnect the adapter from the interior threads at the distal end of the barrel by operation of the flataxial surfaces150dand154k. An important feature of this engagement mechanism is that once the adapter has been disconnected at its threaded connection with the barrel, it along with the remainder of the needle assembly remain attached to theplunger portion154ethrough the snap connection formed byridge154jand groove150c. Thereafter, the plunger and attached needle assembly may be withdrawn into the barrel in the manner illustrated inFIG. 37.
• Clearly, retraction of the contaminated needle into the barrel prevents or substantially reduces the possibility of inadvertent needle stick injuries. Furthermore, as may be appreciated from a consideration of the connection illustrated inFIG. 40, it is another important feature of the engagement mechanism that once theadapter150 has been disconnected from the distal end of thebarrel152, in the absence of extraordinary measures or the use of a special tool, the needle assembly and the adapter cannot be reassembled to the barrel and be reused. Thus, attempts to reattach the adapter to the barrel for subsequent use, illicit or otherwise, is effectively prevented since the spiral grooves and faces of the adapter-plunger connection are shaped in such a manner as to prevent adequate transfer of torque in the proper direction to attain reattachment of the adapter to the barrel by merely rotating the plunger in the direction opposite that illustrated inFIG. 36.
• In use, the exemplary embodiment of syringes as illustrated inFIGS. 33 through 42 are bulk packaged, sterilized, assembled structures of the nature generally illustrated inFIG. 34. Initially, theneedle guard151 is removed, the plunger and attached bung are withdrawn, and the proper dosage of fluid within the syringe body is adjusted using calibration markings (not shown) on the barrel in combination with the straight radial forward edge of the bung157 to obtain a rapid and highly accurate measured reading of the contents. In this regard it must be noted that on conventional syringes the calibration markings, as well as the bung are usually black, with the bung attached to a slightly opaque plunger that is normally of an X cross-section. Additionally, the leading edge of the bung is normally curved outwardly. Accordingly, neither rapid nor accurate readings are obtainable with such structure which includes two interfaces between the bung and the fluid contents and between the bung and the plunger. Such readings are additionally complicated by attempting to distinguish black calibration markings against a black bung.
• As previously noted, the forward surface of the bung157 albeit annular is straight in the radial direction. Moreover, the coloration of the bung and plunger elements are the same so as to obtain a single interface. Moreover, the colors of the materials, as well as the calibration markings, are selected to be contrasting so as to significantly improve the accuracy as well as the speed with which measurements may be taken. As an additional important feature pertaining to rapid and accurate measurements, the cylindrical plunger portion154ais sized to be closely received inbarrel152, thus reducing diffraction and increasing visibility.
• Presuming that the syringe has been used to inject fluid, the plunger is rotated in the manner shown inFIG. 36 and the plunger as well as the needleassembly including adapter150 are withdrawn to the position illustrated inFIG. 37 where the ends of theresilient arms154hregister with annular groove152aso as to retain the needle assembly and lower portion of the plunger in the position illustrated.
• Thereafter, cylindrical plunger portion154amay be broken away at the plunger break point154gin the manner illustrated inFIG. 38. Regarding the narrowed portion of theplunger154f, it is to be noted that although illustrated as being circular in cross section inFIG. 41, it may also take other shapes such as oval in order to enhance the ease with which portion154amay be broken away.
• After portion154ahas been broken away, it may be attached to the threaded distal end of the barrel in the manner illustrated inFIG. 39.
• Thus, subsequent to the intended use the needle assembly has been withdrawn into the barrel and locked in position by way of lockingarm154h, for example. Moreover, the bung and the raised edge ofplunger portion154ewould serve to seal one end of the barrel, whereas portion154aof the plunger may be attached to the threaded end of thebarrel152 by way of the illustrated threaded connection or by other well known snap-fit or friction-fit connections, for example. As illustrated inFIG. 39, not only is the needle withdrawn to a position eliminating inadvertent needle sticks, but the barrel is sealed at both ends thus effectively preventing the escape of any toxic or contagious contents' a feature not seen in the known prior art.
• As illustrated inFIGS. 33-39, the cylindrical plunger portion154aconstitutes a hollow cylindrical sleeve closed at its inner end by the narrowedportion154fand open at its outer end terminating in thethreads154b. As a consequence, when the plunger portion154ais disposed on the distal end of the barrel sealing the latter, the interior of portion154aserves as a reservoir or receptacle open at its proximal end to the barrel of the syringe. Thus, in the unlikely event that the needle is not withdrawn the full distance, as illustrated inFIGS. 37-39, or should the adapter and needle be pushed axially inwardly along the barrel when the syringe is being handled or otherwise disposed, e.g., by other disposables bearing on the exposed end of the portion of the plunger left in the barrel, there is no danger that the needle can be pushed through the barrel or plunger or is otherwise exposed.
• As will be appreciated by the artisan, the selection of materials, coloring, shapes, as well as the location and nature of the seals, used in the embodiment ofFIG. 34, for example, may also find use in other disclosed embodiments. Moreover, it will also be appreciated by the artisan viewing the details of the embodiment ofFIG. 34, for example, that since plunger element154ais hollow and is made sufficiently long as to encapsulate the needle assembly in the position illustrated inFIG. 34, for example, should theadapter150 malfunction and fail to separate from the barrel, the exposed needle assembly may nevertheless be covered by eitherneedle guard151 or by plunger portion154a. In this regard it is to be noted that since the needle guard, as well as the hollow plunger portion, have been made of approximately the same diameter as the threaded end of the barrel, both the needle guard and the plunger portion154amay more safely be installed on the exposed needle in comparison with needle guards of smaller diameter such as is found in the embodiment ofFIG. 32. Accordingly, it will be seen that the design of the embodiment found inFIGS. 33 through 42 includes redundancy features whereby even if the needle assembly fails to disengage and retract after use, it may nevertheless be covered in at least two other ways as discussed above, thus incorporating additional safety features,
• A still further embodiment, which is the presently preferred embodiment, is illustrated inFIGS. 43 through 47. This exemplary embodiment is similar in many respects to the previously recited embodiment as may be appreciated from a comparison ofFIGS. 34 and 43. That is to say,barrel162 ofFIG. 43 is substantially identical tobarrel152 of the previous embodiment except for the elimination of the seal-locking arrangement formed by members such as152aand154dand the inclusion ofelements162awhich, as illustrated in greater detail inFIG. 47, include two annular ridges and an intervening groove on the inside surface at the finger press end of the barrel. As will be seen inFIG. 47, themeans162aof the barrel are designed to cooperate withannular ridge164dincluded inplunger portion164a. As will be recognized by the artisan, the parts can be reversed. That is to say,elements162acan be included on the plunger andelement164dcan be included on the barrel. These elements cooperate when engaged to form an effective seal at one end of the barrel so as to prevent ingress or egress of materials to the central portion of the syringe body until it is used. This seal along with the use of a needle guard of the nature illustrated with the embodiment ofFIG. 34, which may be affixed to thebarrel162 by way ofthreads163, will completely seal both ends of the syringe body. Such sealing, as with the previous embodiment, will allow the syringe to be sterilized and then bulk packaged rather than individually packaged, but nevertheless retain internal sterility. Clearly, this feature will result in beneficial results such as reduced labor and material costs.
• Returning to a consideration ofFIG. 43, it may be seen thatbarrel162 includes an annular groove formed at162bwhich cooperates with theannular sealing ridge160aincluded inadapter160. This groove can be formed in the barrel during the manufacturing process or, preferably, is formed by theridge160aduring assembly due to the resilience of the plastic barrel material. This sealing feature may be seen in greater detail inFIG. 46, wherein the sealing between the adapter and the barrel is clearly enhanced. The embodiment ofFIG. 43 additionally includes modifications toplunger portion164ewhich is substantially different than that of portion154aillustrated inFIG. 34. This plunger portion which is shown in greater detail in bothFIGS. 44 and 45 includes an outercircumferential lip164hwhich is sufficiently reduced in diameter as to snappast barrel ridges162aon assembly, but will be retained at the innermost ridge when the plunger and needle assembly are withdrawn into the barrel. Such withdrawal occurs in the same manner as was explained with regard to the embodiment ofFIG. 34. That is to say the coupling means between theadapter160 and the plunger portion164 are of the same nature illustrated inFIG. 40, and the adapter is uncoupled from the barrel and withdrawn into it in the same manner as was previously explained with regard to the embodiment ofFIG. 34, except that means162aare used to retainelement164ein the withdrawn position.
• Subsequent to withdrawing the plunger and needle assembly into the barrel, thecylindrical plunger portion164amay be broken away at the reduced break point or notch le4g ofportion164f. As with the previous embodiment,narrow portion164fmay be circular in cross section or have other shapes such as oval for aiding in breaking awayplunger portion164a.
• After theplunger portion164ahas been removed, it may be joined to the distal threaded end ofbarrel162 as in the previously described embodiment. As will be appreciated by the artisan, element164 is designed to be attached to the distal barrel end, even if the adapter fails to disengage from the barrel and the needle fails to retract. Moreover, as with the embodiment ofFIG. 34, those skilled in the art will recognize that threaded connections such as formed at163 and164bmay be replaced with other connection means such as snap connections or friction fits of the nature previously described.
• Additionally, as with the previously described embodiment, thebung157 as well as the plunger portions may have similar coloration which additionally contrasts with the coloration of the calibration markings (not shown) on the barrel. Such coloration, as well as the radially linearforward surface167aas detailed inFIG. 46, present a single fluid plunger interface with greatly enhanced visibility as well as accuracy for the reasons previously described.
• Additionally, as with the previously described embodiment, due to the design of the adapter andplunger portion164eand the connection between them, the plunger may be fully compressed without permanent attachment between the elements. That is to say,elements164j, which may be resilient prongs or a resilient annular ridge, maintain the connection while engaged ingroove160c. As with the connection as shown inFIG. 40, the adapter when disconnected from the barrel is retained by theplunger portion164ewhen withdrawn into the barrel. However,elements164jwill release the engagement with the adapter when the plunger is withdrawn without rotation, since the adapter and barrel remain engaged.
• As previously indicated, the artisan will appreciate that the beneficial features of this embodiment, such as the coloration, sealing and locking arrangements, among, others, may be adapted for use in still other embodiments previously disclosed. For example, the embodiment ofFIG. 32 can obviously be modified to accommodate a full size needle guard connected to the exterior of the barrel and may be further modified to include a sealing arrangement of the nature illustrated in eitherFIG. 34 orFIG. 43 at the finger press end. Such modifications would result in preventing the entrance of contaminating materials within the syringe body. Furthermore, the plunger portion containing the threaded connection2S illustrated inFIG. 32 can obviously be modified to be of a hollow circular cylindrical form so as to be usable at the distal end of the syringe barrel whether or not the needle assembly has been retracted into the barrel.
• A further modification to the embodiment ofFIG. 43 may be found in the further exemplary embodiment illustrated inFIGS. 48 through 50. This embodiment is similar in most respects to the embodiment ofFIG. 43 except that the narrowed intermediate portion of the plunger (164fand174fof the respective embodiments) includes as a substitute for the break point (164g) a connection means whereby the hollow cylindrical portion of the plunger may be unlatched or disconnected from the needle end portion and subsequently re-attached thereto. Such construction allows the hollow finger press portion of the plunger174ato be used as a needle guard both before and after use, as well as a plunger portion during use.
• As may be seen from a consideration ofFIGS. 43 and 48, the needle end plunger portions (164eand174e, respectively) are substantially the same except that the narrowedintermediate portion164fwithbreak point164ghas been replaced with arectilinear locking mechanism174fhaving a rectangular shapedsocket1741 with two resilient wings orside arms174mthat are slightly flared in the outward or radial direction.
• The upper ends of these two arms includelips174nwhich are arcuate and which have an internal groove174owhich is also arcuate.
• The plunger portion174aas in the embodiment ofFIG. 43 is a hollow cylindrical cylinder in cross section. However, the needle end portion thereof has been modified as illustrated inFIGS. 48 and 49 to include arectilinear portion174kwhich is complementary to therectilinear portion174f. Accordingly, when these portions are joined, bothportions174aand174ewill rotate as a unit. Moreover, since the adapter/plunger engagement structure in this embodiment is the same as that found in the embodiment ofFIG. 43, for example, unidirectional rotation of the adapter will be obtained in the previously described manner when the plunger is rotated.
• As will be further noted from a comparison ofFIGS. 43 and 49, for example, the same type of sealing at the finger press end of the syringe comprising complementary ridge arrangements are included in the embodiment ofFIGS. 48 through 50. It will be noted, however, that the finger press end of thebarrel172 has been tapered so as to allow thearms174mto flare outwardly and unlock or disengage from the complementary grooves included in plunger portion174a.
• In operation the sterilized syringe is supplied with cylindrical portion174aconnected over the needle and in sealing engagement with the distal end of thebarrel172. In this regard, although the sealing engagement is illustrated as a threaded connection, other connection means as previously described may be used. As supplied, the syringe would also include the adapter and needle assembly connected to the distal end of the barrel but with theplunger portions174eand174falong with bung17 withdrawn into the barrel and in sealing engagement with the finger press end of the barrel in the same manner noted with regard to the embodiment ofFIG. 43. Additionally,arms174mwould be positioned as illustrated inFIG. 49. Accordingly, as supplied, both ends of the syringe would be sealed, thus maintaining sterility as to the enclosed portions of the syringe body. Additionally, once the syringe is used the needle end portion of the plunger along with the adapter and needle assembly may be withdrawn and plunger portion174adisconnected, as illustrated inFIG. 49. Thereafter, the disconnected plunger portion174amay be reconnected as before to the distal needle end portion of the barrel so that both ends of the syringe are again sealed whereby toxic or contagious material within the syringe body cannot escape. Moreover, as with the embodiment illustrated inFIG. 43, plunger portion174amay be re-attached to the barrel as a needle guard whether or not the needle assembly has been withdrawn into the barrel.
• Clearly the modification illustrated inFIGS. 48 through 50 offers the advantage whereby a single element (174a) may be used both as a needle guard and as a portion of the plunger through the use of the disclosed rectilinear locking mechanism. Moreover, the previously described sealing and locking arrangements and their beneficial results may be maintained. Additionally, the previously described beneficial results to be obtained by the shape and coloration of the elements whereby visibility and accuracy of measurement of the syringe fluid contents may also be applied to the embodiment ofFIGS. 48 through 50. Furthermore, the artisan will appreciate that the beneficial feature of this embodiment may be adapted for use in still other embodiments previously disclosed.
• As will be recalled, a further feature of the present invention provides for a venting structure in the adapter for venting air from the interior of the barrel once the barrel has been substantially filled with fluid to be injected and prior to injection. It will be appreciated that in those embodiments hereof where the hub or adapter has structure which protrudes into the barrel from the distal end of the barrel, there is formed an annular space between such protrusion and the barrel. With the central passage through the adapter and needle terminating inwardly of the distal end of the barrel, there is the danger of entrapment of air within the annular space between the protrusion and the barrel adjacent the distal end of the barrel. The following is a description of a specific embodiment of the present invention which eliminates any such air and vents the entirety of the air in the barrel prior to injection. The concept and structure of this embodiment are applicable to the previous embodiments, for example, to thehub6 of the embodiments ofFIGS. 5, 8,10,15 and17, theadapter102 of the embodiments ofFIGS. 26-32 and theadapter150 of the embodiments ofFIGS. 33-42, and theadapter160 of the embodiment ofFIG. 43.
• Turning now toFIG. 51, there is illustrated anadapter200 substantially identical to the adapter illustrated inFIG. 40, with the further improvement of the vent openings, as will now be described.Adapter200, of course, has a centralaxial passageway202 defined in part by the protrusion '204 of the adapter into the barrel and on which protrusion is mounted the spiral threads orsurfaces206, terminating in theannular groove208, all as previously described.Adapter200 is threaded into the end of the barrel, as illustrated inFIG. 52, similarly as the embodiment ofFIG. 40.
• In this form, however, there is provided at least one and preferably a pair ofvent passages210 extending radially from and in communication with the centralaxial passageway202. These passages preferably extend ingrooved portions212 formed in the face of the flange facing the proximal end of the barrel. Additionally, that face is tapered radially inwardly in a direction toward the needle end of the barrel, for example, on the order of about 3″. Further, an annular trough or groove211 is preferably formed in the tapered flange face about the base ofprotrusion204. Groove211 lies in communication withgrooved portions212 and ventpassages210. One or more additional annular grooves may also be provided including about the outer margin of the tapered flange base or at intermediate radial positions. By grooving thepassageway portions210 and groove(s)211 in the face of theadapter200 and tapering that face, thegrooves211,212 andpassage portions210 will assume the most superior position within the interior of the barrel when the syringe is oriented vertically with the needle uppermost. Consequently, when the plunger is advanced toward the needle end to vent air from the interior of the barrel, any air trapped within the annular space214 between the distal end of the barrel andprotrusion204 will vent through the grooves and openings into the central passageway. Hence, the interior of the barrel may be purged of any air prior to injection. It will be appreciated that there may be only asingle vent passage210, although preferably at least two such passages diametrically opposed to one another are provided. More than two such passages may also be provided, preferably equally spaced about the axis of the adapter.
• Referring now to the embodiment ofFIG. 53, the central passageway202aterminates short of the distal end of the protrusion204a. Consequently, the central passage202acommunicates only with the one or more radially extending passages210aand grooves211a,212a. In this form, not only do the passageway portions210aand grooves211a,212aform the superior positions when the syringe is oriented vertically with the needle uppermost to enable venting air from the barrel and particularly the annular space214abetween the barrel and protrusion204a, but provide the sole passageway portions for egress of fluid from the interior of the barrel through the central passageway202aduring injection. The opening216 in the end of protrusion204ais in the form of a multi-sided opening, e.g., a hex-shaped opening, for purposes of receiving a tool for assembling the syringe. Thus, a tool may be inserted through the opposite end of the barrel and received in opening216 to thread the adapter onto the barrel.
• Referring now to the embodiments of the invention illustrated inFIGS. 54-56, three forms of syringes having tamperproof features are disclosed, respectively. InFIG. 54, there is illustrated a syringe having abarrel300, afinger press302 for the plunger, and aneedle guard304. The needle guard is, of course, screw-threaded or otherwise secured to the end of thebarrel300, for example, as illustrated inFIGS. 33 and 34. In this form of the invention, astrip306 of paper or other material, such as plastic, having adhesive along one side thereof is applied along a side of the syringe. Particularly, the strip is applied along the side of thebarrel300 and onto the end of theneedle guard304 at its juncture with thebarrel300. The opposite end of thestrip306 is applied to thefinger press302 and preferably extends across the top of the finger press and partially down the opposite side to at least the cylindrical barrel portion. In this manner, the juncture between thefinger press302 and barrel is spanned by at least a portion of thestrip306. As a result, it will be appreciated that any inadvertent or attempted removal of the needle guard from the barrel or rotational or axial movement of thefinger press302 relative to the barrel will cause thestrip306 to tear or become twisted whereby the disruption of the seal at these junctures and possible tampering with the syringe will be indicated.
• InFIG. 55, another form of tamperproof syringe is disclosed. In the embodiment illustrated inFIG. 55, the barrel, finger press and needle guard are indicated as inFIG. 54 with the suffix “a” applied thereto. In this form, thin-film plastic material308 and310, respectively, is applied, for example, by heat-shrinking, about each of the junctures between theneedle guard304aandbarrel300aon the one hand and thebarrel300aand finger press andplunger portion302a, on the other hand. Once again, any rotary movement or other movement of theneedle guard304arelative tobarrel300aor rotary or axial movement of thefinger press302arelative tobarrel300awill be detected by the severing of the shrink-wrapped plastic material or its wrinkling whereby disruption of the seals at the opposite ends of the syringe or tampering with the syringe will be indicated. It will also be appreciated that the shrink-wrap of plastic material assists in maintaining the sterility of the syringe and that suitable tear strips may be provided along each of the shrink-wrapped portions to facilitate their removal and use of the syringe.
• InFIG. 56, the like elements of the syringe are illustrated by like reference numerals as inFIGS. 54 and 55, followed by the suffix “b”. In this form, the syringe is dipped into a melted plastic material whereby a thin-film coating ofplastic312 is applied about and completely envelops the syringe with the needle guard attached and plunger located in its axially innermost position. For example, theplastic coat312 may comprise a clear chlorinated polyvinyl chloride coating (CPCV). The ingredients are vinyl chloride-vinyl acetate resin silicon dioxide (amorphus) with a methol isobutyl ketone base. This is an air dry coating. The drying can be accelerated by raising the temperature to 100° F. The melting temperature of the plastic material is, of course, less than the melting temperature of the plastic forming the syringe, and it will be appreciated that a clear plastic material should be used such that the gradations and other information on the syringe may be visualized through the thin-film plastic coating. Thus, any efforts to remove theneedle guard304bor displace the plunger will be immediately detectable by the break in the thin-film12 of plastic material, hence indicating disruption of or tampering with the seals adjacent the opposite ends of the syringe. The coating material is, of course, sufficiently thin to enable the needle guard to be readily removed from the barrel and the plunger to be readily rotated to break the seal, hence permitting axial movement of the plunger relative to the barrel. Therefore, the plastic coating can be left on the syringe barrel during use, eliminating the need to physically strip it from the barrel and dispose of it separately.
• With respect to each of the tamperproof configurations illustrated inFIGS. 54, 55 and56, respectively, the tamperproof features may also be provided with integral indicators which change color or become visible after exposure to sterilizing radiation. Thus, thestrip306 ofFIG. 54, the thin-film plastic material308 and310 ofFIG. 55 and the hot meltedplastic coat312 ofFIG. 56 may be provided with integral sterilizing radiation indicators such as ethylene oxide or other sterilizing agents which change color or become visible after exposure to sterilizing radiation. Consequently, not only can it be determined at the point of use of the syringe that the syringe has not been tampered with but also there is assurance by the change of color or visibility of the indicators that the syringe has been sterilized.
• Referring now to the embodiments hereof illustrated inFIGS. 57, 58 and59, the barrel, plunger, and adapter are formed similarly as in previous embodiments, for example, as in the preferred embodiment hereof illustrated inFIGS. 33-40 using the adapter illustrated inFIGS. 51-53. The syringe is illustrated inFIG. 57 prior to use and before a ferrule with attached needle, e.g., as illustrated inFIGS. 33 and 48, is attached to the adapter. In this form, there is provided anend cap400 having female threads for threadedly engaging corresponding male threads on the distal end of the barrel, for example, the male threads at the barrel end illustrated inFIGS. 33 and 48. In the previous embodiments, for example, with reference toFIGS. 35-39, upon withdrawal of the adapter and needle within the barrel, the proximal end of the plunger may be broken off and reapplied to the distal end of the barrel by screw-threading the plunger and barrel to one another. There is, however, the psychologically discomforting possibility of contacting an individual's hand with the barrel end, notwithstanding the withdrawal of the needle into the barrel, prior to the threaded attachment of the proximal plunger end portion to the distal end of the barrel. Consequently, for those syringes wherein the adapter carries a Luer lock male fitting which releasably receives the ferrule of the needle, i.e., the needle is not directly or integrally attached with the adapter, the syringe may be provided as illustrated inFIG. 57 with acap400 screw-threaded on the distal end of the barrel. As illustrated, thecap400 has a flatexternal surface402 opposite the otherwise open end of the cap.
• InFIG. 58, thecap400ais similarly provided with internal female threads at its open end for connection with the male threads at the distal end of the barrel. The closed opposite end of thecap400a, however, has featherededges404 in conjunction with a concavity or recessedface406 in the central portion ofcap400a.
• A further form of cap is illustrated inFIG. 59. InFIG. 59,cap400bhas, as indicated previously, internal female threads about its open end for threadedly engaging the male threads on the end of the barrel. At its closed end, there is provided aring408, theouter surface410 of which carries an adhesive, preferably a pressure-sensitive adhesive.Ring408 may have adhesive along its opposite side for adhesively securing it to the closed end ofbarrel400b. A release membrane orpaper portion412bmay be provided along the outer surface of the ring overlying and protecting the pressure-sensitive adhesive410.
• Referring now to drawingFIG. 59A, there is illustrated a cap400cwhich may comprise any one of thecaps400,400aand400band which has the features described with respect to those caps. In addition, the cap400cincludes a flexible hinge414 which connects the cap to the body of the barrel of the syringe, it being appreciated that other types of hinges may be employed. Various methods may be used to connect the hinge to the syringe barrel, for example, the distal end of the hinge414 may comprise a ring or band416 disposed about the cylindrical syringe barrel. As a consequence of this construction, the cap remains integrally attached to the syringe and is thus readily available after the syringe has been used to close the open and possibly contaminated end of the syringe barrel. Additionally, the cap and barrel or band or ring surrounding the barrel may have parts cooperating with one another to retain the cap414 in a position which does not interfere with the normal usage of the syringe, i.e., when the needle projects from the syringe barrel end. To accomplish that, the barrel or the band or ring about the barrel and the cap may have cooperable releasable elements. For example, the band and cap may have Velcro

  

  securements or areas of adhesive or mechanical interconnections such as a snap-fit, i.e., a pin and recess, so that the cap may be releasably retained in a non-interfering position as illustrated by the dashed lines.
• Referring now toFIGS. 60-62, the use of the caps illustrated inFIGS. 57-59 will be described in conjunction with the illustrated use of the cap58. Instead of passing the proximal plunger end portion broken from the plunger, as illustrated inFIGS. 3-4,25a-25c,38,39 or49, in front of the barrel for connection therewith or passing the user's hands or arms adjacent the barrel end after use of the syringe, acap400,400aor400bmay be placed on a table or other flat surface with its open end facing upwardly. Note that once the cap is removed from the syringe prior to use, the cap is not contaminated by any body fluids. After use, the syringe may be applied to the cap. Thus, as illustrated inFIG. 60, the proximal end of the plunger may be broken from the plunger barrel, leaving that end of the barrel sealed by the plunger bung. Instead of applying the broken-off plunger end to the distal end of the barrel, it may be discarded and the distal end of the barrel may be applied to the cap. Particularly, by inserting the distal end of the barrel into the open end of the cap and exerting downward pressure on the barrel, the first few threads of the barrel may ratchet past the female threads on the cap to engage the barrel and cap one to the other. Note that the user's hand or arm need not pass in front of the possibly contaminated barrel end in order to close the barrel end with the needle retracted into the barrel.
• While this axial engagement of the barrel with the cap may be sufficient to secure and seal the barrel end, the barrel is preferably rotated relative to the cap to ensure a tight, snug sealing fit between the barrel and cap. When using the flat-endedcap400 illustrated inFIG. 7, the cap, after its initial securement to the barrel end, may be grasped and rotated relative to the barrel. Alternatively, when using the cap illustrated inFIG. 58, the downward pressure of the barrel on thefeathered edges404 of the cap causes the cap to displace air between its recessed,closed end406 and the flat surface whereby the cap serves as a suction cup releasably adhering the cap to the surface. Consequently, once the barrel has been applied to the cap, the barrel may be rotated with the suction effect tending to maintain the cap against rotation on the flat surface. Also, the suction effect prevents the cap from sliding laterally along the flat surface. Once the barrel and cap are secured one to the other by downward pressure and relative rotation, a slight rocking motion, as illustrated inFIG. 62, will dislodge the cap from the flat surface and break its suction grip therewith.
• In the embodiment illustrated inFIG. 59, thecap400bmay haverelease paper410 on theannular ring408. By removing the release paper and releasably adhesively securing thecap400bto the flat surface, the barrel can be applied thereto and rotated relative to the cap similarly as with the embodiment ofFIG. 58. The rocking motion illustrated inFIG. 62 will also release the adhesive from the surface whereby the syringe with its capped and sealed end may be removed from the adjoining surface. Also inFIG. 59, it will be appreciated that theannular ring408 may comprise a disk or discrete areas of adhesive. Further, instead of release paper, the plastic tamperproof packaging illustrated in FIGS.54 to56 may be used. For example, the strip of paper or other material illustrated inFIG. 54 may be enlarged at the lower end to overlie the pressure-sensitive adhesive such that the paper wrap or shrink wrap which affords a tamperproof feature may also serve as the release paper for the adhesive. The shrink wrap ofFIG. 55 may also be employed as the release paper for the embodiment hereof illustrated inFIG. 59, the shrink wrap being illustrated inFIG. 59 at412 and the portion thereof overlying the adhesive illustrated at412b.
• Of course, the embodiment illustrated inFIG. 59A is used similarly as previously described with respect to the caps ofFIGS. 57-59. In the embodiment ofFIG. 59A, however, the cap is releasably retained in a non-interfering position and may be readily displaced from that position to the syringe barrel closed position.
• Referring now to the embodiment hereof illustrated inFIGS. 63 and 64, it is advantageous to preclude the needle from exposure after use, whereby the risk of needle stick injury may be entirely avoided. That is, if the needle can be removed from the injection site and into the barrel without exposing the thus contaminated needle, the risk of needle stick injury is substantially prevented.
• In this embodiment of the invention, the syringe is virtually identical apart from the distal end of the barrel. In this form, the distal end of the barrel is elongated as illustrated at500 inFIG. 63. Theelongated end portion50 of the barrel may be externally threaded to receive the cap of the previous embodiment or the female threads at the opposite end of the plunger once the latter is broken from the syringe as previously described. Also, while theneedle502 in this embodiment is illustrated as integrally attached to the adapter504 (which may take the form of any one of the adapters previously described), the adapter may be provided with the Luer tip for receiving the hub of a standard Luer needle. In both cases, the end of the adapter or the hub of the Luer needle is recessed within and lies short of the end of the elongatedbarrel end portion500. Only theneedle502 or a portion thereof is exposed through the barrel end.
• With this arrangement and as illustrated inFIGS. 63 and 64, the needle penetrates the injection site, i.e., the individual's skin Sk. The end of the barrel is also brought into engagement with the skin as the needle penetrates further into the skin, as illustrated inFIG. 63. The plunger is then depressed, injecting the fluid through the needle into the individual. Following the injection and with the barrel end of the syringe still pressed against the skin, the plunger is rotated and coupled with the adapter, as previously described, and the adapter with the needle is withdrawn with the plunger within the barrel, as illustrated inFIG. 64. In this manner, the contaminated needle is never exposed to the risk of needle stick injury. After the barrel is removed from the skin, the cap or the broken plunger portion may be secured and seated to the elongated barrel end as previously described.
• Referring now to the embodiment hereof illustrated inFIGS. 65-69, there is illustrated asyringe barrel600 carrying anadapter602 screw-threaded at604 into the distal end of thebarrel600. Theadapter602 includes a Luer fit606 for mounting thehub608 of a needle, not shown in this drawing figure. Note in the drawing figures, theannular ridges617 projecting from the forward face of the adapter along the inside face of the annular shoulder at the distal end of the barrel. These ridges assist in performing a sealing function when the adapter is screw-threaded into the distal end of the barrel. Aplunger610 is mounted for axial movement within the barrel and includes a bung612 at its distal end in sealing engagement along the interior side walls of the syringe barrel. The plunger is, of course, mounted for axial sliding movement within the syringe barrel for injecting fluid from within the barrel through the adapter and Luer fit into and through the needle and for drawing fluid into the barrel, for example, from a vial, not shown. The bung is formed of a Santoprene compressible material and has a plurality of circumferentially extending ribs for forming sealing engagements with the interior walls of the barrel. Theplunger610 includes at its distal end a central portion orprojection614 carrying a plurality of axially spacedribs616 for engaging and sealing with interior wall surfaces ofbung612.
• In this form of the invention, thecentral portion614 includes an axially extending male projection615 having a plurality of discrete angularly related axially tapered sides or faces618. In the illustrated form, theprojection618 is hexagonal in cross-sectional configuration, with the sides being tapered toward the distal end of the barrel. Spaced axially from the tapered sides is a continuously circumferentially extending radially outwardly projectingrib620 directly adjacent a continuous circumferentially extending radially inwardly directedgroove622. Thesurfaces618,620 and622 comprise adapter engagement structure disposed at the distal end of the plunger for engagement with complementary or mating engagement structure carried by the adapter.
• The inner face of theadapter602 is tapered toward the central axis of the adapter and has arecess624 substantially complementary in shape to the male projection615 on the plunger. Specifically, therecess624 includes a plurality of tapered sides or faces626 complementary in shape or taper to thefaces618, as well as a continuous circumferentially extending radially inwardly directedrib628 and a continuous circumferentially extending radially outwardly projecting groove630.
• The opposite end of theplunger610 includes a radially outwardly projecting continuously circumferentially extendingrib634. A pair of radially inwardly projectingribs636 and638 are formed about the inner surface of the proximal end of the barrel defining a continuous radially outwardly extendinggroove640 therebetween.
• In this form of the invention, it is desirable to permanently or irreversibly lock the plunger and the adapter to one another when the plunger is finally seated in its axially innermost position within the syringe barrel such that the plunger and adapter act as a unit and cannot be axially disconnected one from the other. In this manner, the plunger and adapter can be locked permanently one to the other only with firm positive axial pressure intentionally exerted on the plunger relative to the barrel. This requires a deliberate strong axial force to be applied to the plunger to effect the locking action. It also makes it unnecessary for the user to maintain forward axial pressure on the plunger when rotating the plunger to unthread the adapter from the barrel. In use, the plunger is advanced toward the adapter such that the radially outwardly projectingrib620 engages the inwardly projectingrib628 on the adapter with the distal end of the plunger received in the recess of the adapter, as illustrated inFIG. 66. The user is thus able to recognize from this initial engagement and hence initial resistance to further axial movement of the plunger relative to the barrel that the plunger is just axially short of being finally seated and locked relative to the adapter. At this time, the user is thus signalled that the plunger and adapter will be permanently locked to one another upon further axial displacement of the plunger relative to the barrel. Upon such further forceful axial displacement and as illustrated inFIG. 67, therib620, due to the compressibility of the plastic materials principally of the plunger, slips past therib628 on the adapter and seats in the groove630. Correspondingly, the radially inwardly directedrib628 seats in thegroove622 of the adapter, thus permanently locking the plunger and adapter to one another. As the plunger is axially advanced from its position short of the finally seated position relative to the adapter, i.e., from the position illustrated inFIG. 66 to that ofFIG. 67, toward the distal end of the barrel, thebung612 compresses, as illustrated inFIG. 67. This ensures, once the plunger and adapter are retracted into a final position within the barrel, a further effective sealing action at the opposite end of the barrel. With the rib and groove engagement of the plunger and adapter, the plunger may be rotated to unscrew the adapter from the distal end of the barrel. Thus, by withdrawing the plunger from the barrel, as illustrated inFIG. 68, the adapter and needle carried thereby are withdrawn into the interior confines of the syringe barrel. By breaking the plunger off at its weakened portion, as previously described, the plunger may be threaded onto the distal end of the barrel, as illustrated inFIG. 73. With the plunger bung sealing the opposite end of the barrel and the plunger threaded on the distal end of the barrel, the barrel is sealed at its opposite ends.
• Referring to the embodiment hereof illustrated inFIGS. 69-71, like reference numerals as in the prior embodiment are applied to like parts, followed by the suffix “a.” In this embodiment, the bung612ais releasably retained in a first axial position relative to the projectingportion614aof the plunger as illustrated inFIGS. 69 and 70 and a second axial position spaced from the first axial position, illustrated inFIG. 71. To accomplish this, the projecting portion14aof the plunger end carries a plurality of radially outwardly projecting axially spaced flaredribs650 whereas the interior surface of the bung612acarries a plurality of axially spaced complementary shaped circumferentially continuoustapered ribs652. Theribs650 and652 are configured such that the complementary inclined surfaces thereof engage one another in the first or initial axially extended position of the bung612arelative to the plunger, as illustrated inFIGS. 69 and 70. As the plunger is advanced to engage theribs620aand628ato form the initial stop position, the annular end wall surface ofbung612aengages the interior axial face of the adapter602a. Upon firm pressure being applied to the plunger to displace it axially into its final seated position, as previously described, this forceful axial pressure enables the plunger to slide relative to the bung such that the complementary inclined surfaces slide past one another and the radial surfaces of theprojections650 and652 engage one another, as illustrated inFIG. 71. Thus, once the plunger and adapter are permanently locked one to the other as illustrated inFIG. 71, the plunger and adapter can be jointly rotated to unscrew the adapter from the barrel end for location of the adapter and needle carried thereby axially into the barrel, with the radial surfaces of theribs650 and652 engaging one another to carry one the plunger bung axially with the plunger upon withdrawal of the plunger.
• Referring now to the embodiment hereof illustrated inFIG. 72, wherein like parts as in the prior embodiments are illustrated with like reference numerals, followed by the suffix “b,” there is provided a plunger having, instead of a bung, a radially outwardly directed flange65gforming an interference fit with the interior wall of the barrel. The flange658 is weakened at660 to enable the flange to flex. Axially beyond the flange, the plunger includes the projectingportion615bshaped similarly as previously described and complementary to therecess624bin the adapter. Once the plunger has been advanced such that the ribs620band628binitially engage one another, the flange bears against the inner face of the adapter. When final locking is desired, the plunger is advanced forwardly into its permanently seated and locking position relative to the adapter. The weakenedportion660 of the flange enables this final axial advancement of the plunger between the initial and final seated positions with the flange deforming at its weakenedportion660.
• It will be appreciated that a reverse configuration of the male and female parts on the plunger and adapter, respectively, illustrated inFIGS. 65-72 may be employed, for example, with the type of plunger and adapter illustrated inFIG. 40. Thus, a radially outwardly projecting rib may be provided on the male projection ofadapter150 ahead ofgroove150c. The initial engagement of the radially inwardly projectingrib154 on the female end of the plunger with the radially outwardly projecting rib in advance of thegroove150conadapter150 provides the initial resistance or stop to finally locking the plunger and adapter to one another. By further forceful axial pressure on the plunger, the ribs slip past one another to finally lock the adapter and plunger to one another. Of course, the reverse of this arrangement may likewise be used, i.e., the rib and groove being located on the plunger and only a radial outwardly directed rib being located on the adapter.
• It will also be appreciated that other types of permanent locking connections may be provided between the plunger and adapter. For example, complementary sawtooth ribs may be provided with their inclined surfaces engaged to provide the initial resistance and being movable past one another to engage the radial surfaces thereof to permanently lock the adapter and plunger to one another. Further, it will be appreciated that either of the male or female latching structures of the plunger and adapter, as the case may be, can have one or more axially extending slits to facilitate relative axial movement of the plunger and adapter toward their permanently locked position and without detracting from the ability of the rib and groove (or complementary sawteeth) to permanently engage one another. Also, the ancillary features of the present invention described herein such as the air venting feature of the adapter illustrated inFIGS. 51-53, the tamperproof features ofFIGS. 54-56 and the cap arrangements ofFIGS. 57-64 may be employed with the permanent locking feature of the embodiment ofFIGS. 65-77.
• Referring now toFIGS. 78 and 79, there is illustrated an arrangement of anadapter700 and aplunger end702 having abung704. Theadapter700 andplunger end702 are similar to the adapter and plunger end illustrated inFIG. 40, except that theadapter700 has afemale recess706 and theplunger end702 has amale projection708 generally complementary in shape to thefemale recess706. That is, while the adapter and plunger end combination ofFIG. 40 have the male and female parts on the adapter and plunger end, the adapter and plunger end illustrated inFIG. 78 have a reverse configuration and with similarly functioning elements. Thus,adapter700 hasexternal threads710 for threaded engagement with the threads712 (FIG. 79) at the barrel end of the syringe for sealing the barrel. Theadapter flange714 has a generally frustoconicalshallow recess716 opening into therecess706. The base ofrecess706 is provided withteeth718 which haveflats720 andangled surfaces722. Additionally, therecess706 includes a projectingannular rib724.
• Themale projection708 onplunger end702 is shaped for reception in therecess706 and has complementary-shapedteeth726. That is,teeth726 haveflats728 andangled surfaces730 which engage theflats720 andangled surfaces722 in therecess706 ofadapter700 when the plunger is fully axially advanced in the syringe barrel. Themale projection708 also includes a radially inwardly directedannular groove732.
• The cooperation of the teeth and the rib and groove are similar as previously described, particularly with respect to the embodiment ofFIG. 40. For example, when the plunger is advanced in the barrel to engage theprojection708 inrecess706, the engagement structure enables the plunger to rotate relative to the adapter and barrel to bring theflat surfaces728 into alignment with theflats720 of the adapter. Once aligned, joint rotation of the plunger and adapter unthreads the adapter from the end of the syringe barrel. It will be appreciated as illustrated inFIG. 79 that when the plunger is axially advanced to its fullest extent, therib706 engages in thegroove732 to enable joint withdrawal of the plunger and adapter once thescrew threads710 are disengaged from thebarrel threads720. The rib-and-groove arrangement may, of course, be reversed with the groove located on the adapter and the rib on the plunger.
• A particular feature of this arrangement is that the cost of materials for forming the adapter is substantially reduced. The adapter is preferably formed of a polycarbonate material and, by forming the female recess in the adapter, a significant reduction in material is achieved in comparison with the arrangement of the adapter illustrated inFIG. 4. Functionally, however, the cooperation of the male and female parts as illustrated inFIGS. 78 and 79 is the same as illustrated inFIG. 40.
• It will be appreciated that the foregoing description and illustrations disclose a plunger which is cylindrical over the major portion of its length. It will be appreciated, however, that the cross-sectional configuration of the plunger may be other than cylindrical, at least between the cooperating ridges andgrooves162 and164 at the proximal end of the plunger and the rib on the bung which cooperates with the groove in the distal barrel end when the adapter has been withdrawn to seal the proximal end of the barrel. Thus, the cross-sectional configuration of the plunger need not be cylindrical but can be cruciform, solid cylindrical, or only partly cylindrical, or any other configuration whereby the opposite ends of the plunger are connected one to the other and the plunger may be broken off as illustrated.
• While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope the appended claims.

Claims (2)

1-12. (canceled)

13. A syringe comprising:

a hollow axially elongated barrel having distal and proximal ends;

a needle carrier releasably secured to said distal end of said barrel and having non-deformable exterior wall surfaces releasably securing said needle carrier along interior wall surfaces of said distal barrel end;

a hollow needle carried by said carrier and in communication with the interior of the barrel;

a plunger axially slidable in said barrel and having a thumbpress at a proximal end thereof and external to said proximal end of the barrel, said plunger including a bung adjacent an opposite end thereof and within the barrel;

an element carried by said opposite end of said plunger and engageable with a mating element carried by said needle carrier, one of said elements including a laterally projecting rib and another of said elements including a groove, said one element snapping over said another element with said rib engaging in said groove to secure the elements to one another in response to axial movement of said plunger toward said distal end of the barrel and into engagement with said carrier;

said element in engagement with said mating element carried by the needle carrier enabling detachment and removal of said needle carrier with said needle from said distal end of the barrel and withdrawal of said needle carrier and said needle into the barrel in response to axial sliding movement of the plunger away from the distal end of the barrel.

Images