KR100673284B1 - Disposable Shrink Needle with Positive Needle Retention - Google Patents

Abstract

The disposable shrink syringe of the present invention comprises a handle portion and a needle holding portion in front of the handle portion, the needle holding portion functioning as a plunger, and the handle also moves forward beyond the forward end of the injection position. It is desirable to function to trigger a contraction mechanism when The positive fastening structure in the syringe barrel allows one pull out of the handle in the backward direction to fill the variable fluid chamber and one move in the forward direction to empty the variable fluid chamber, but then the needle holding chamber and / or the back of the handle Restriction of movement ensures that the syringe cannot be reused even if the user forgets to trigger the retraction device to retract the needle. In one embodiment, the positive fastening structure is a stop in the syringe barrel, which allows the radial extension of the needle retainer chamber to move beyond the fastener and move in two directions with a detachable handle. The handle portion is removed after only one use and is removed from the syringe without causing the needle or needle retention chamber to be pulled out by the barrel. In a second embodiment, the handle behind the needle holding chamber includes a plurality of stepped teeth and clips that are movable relative to both the handle and the barrel. After one use of the syringe, the tip on the clip penetrates into the inner surface of the barrel to prevent backward movement. In a third embodiment, the positive fastening structure is constructed of a barrel having elastic tips protected from a plurality of stepped teeth on the handle by a sliding collar that can move in only one direction with respect to the handle similar to those of the second embodiment. It is a clip fixed in the extended rear opening. After single use, the slide collar slides forward with the handle so that the handle can be fully pressed to perform an injection. Certain attempts to withdraw the handle after a single injection are prevented by the tip penetrating into the tooth on the handle. Since the handle cannot be withdrawn at the second time, the syringe cannot be refilled. One use feature disclosed herein can be applied to a non-shrink syringe to prevent reuse.

Fastening structure, tip, tooth, handle, shrink syringe

Description

One-use retracting syringe with positive needle retention}

The present invention relates to medical devices for fluids, in particular syringes having a retractable needle that cannot be reused after an injection has been made.

Such syringe technology has developed rapidly in recent years due to the threat of consequent accidental needle injection that health managers may encounter when using needles for AIDS and other infectious diseases and infected patients. Used syringes with extended needles present a danger to medical personnel, sanitary workers and others in the disposal class. The prior art generally discloses a number of syringes and other medical devices having a retractable needle that is retracted into or into the needle receiving chamber in the syringe barrel. The most advanced shrink syringes are described in US Pat. No. 5,385,551, which is incorporated herein by reference and is entitled by Applicant; 5,578,011; 5,632,733; 6,015,438 and 6,090,077. The syringe described in this patent is automatically retracted by continuously pushing the plunger handle during the end of the infusion, providing one-handed handling and retraction of the syringe so that the health care manager does not need to be exposed to contaminated needles at all. Plunger actuated automatic retraction of these devices takes place before the needle is removed from the patient. These shrinkable syringes have high reliability and repeatability of operation and are suitable for low cost mass production. They are suitable for the automatic manufacture of parts and the automatic assembly of many different barrel sizes, needle sizes and different uses.

Although the aforementioned syringes and other shrinkable syringes have the problem of needle injection removed or significantly reduced, on the one hand, there is a need for disposable syringes that cannot be reused under certain circumstances. Most, if not all, shrink syringes require the user to perform some action to initiate the contraction of the needle after the injection is made. It is possible that a retractable syringe will be reused if it forgets to retract the needle after a single use. A solution to this problem has been proposed by various devices for mechanically fastening the plunger handle after the initial use of the syringe in the case of a non-shrinkable syringe, but none of these devices have a shrinking needle. Thus, since the needle cannot withdraw the second plunger, it remains exposed to the possibility of continuous needle injection even if the syringe cannot be reused. An example of a syringe with a fastening plunger handle that is not shrinkable is US Pat. No. 5,000,737, Allison et al., Entitled "Disposable Syringe" by Free et al., And "Insert element for preventing reuse of plastic syringes." "US Pat. No. 5,205,825, Kosinski's invention" Disposable Syringe "US Pat. US Pat. No. 5,531,691, entitled “Disposable Syringe Assembly,” and US Pat. No. 5,562,623, entitled “Disposable Syringe Assemblies with Elastic Clip Fasteners and Plungers”. The contents of these patents are incorporated herein by reference.

The disposable syringe described above cannot be reused after one injection has been made, but the contaminated needle is still extended and must be covered or removed or otherwise taken before the syringe is safe. Thus, there is a need for a disposable, improved syringe with a needle that shrinks into a syringe barrel after use, whether or not the needle can be retracted or not reused.

The present invention is a disposable shrink syringe having a handle operated needle holding chamber that cannot be removed from the syringe barrel. Contractile properties eliminate the risk associated with exposed needles after injections are made. The active fastening structure makes the syringe a truly disposable syringe and cannot be reused. In various embodiments, the movable portion, including the handle portion and the needle holding chamber, is received in the syringe barrel and moved backwards after a single forward movement of the handle for filling the syringe with liquid and a single forward movement of the handle for ejecting liquid from the syringe. This is limited. The present invention functions to eliminate the risk that shrinkable syringes that contract after a single use are likely to be reused due to the operator not operating or closing the contraction mechanism and leaving the needle exposed for second use. This impossibility arises due to the active fastening structure which prevents the removal of the needle holding chamber by blocking its removal. The needle holding chamber is held in the barrel whether or not the contracting mechanism is activated and whether the needle is contracted or not. This suggests that the advantages of the present invention can also be applied to non-shrink syringes in which the needle is fixed to the front end of the barrel, which is considered as another aspect of the invention described herein. In non-shrink syringes, the present invention works in the same way to limit or prevent the withdrawal of the handle (plunger) from the barrel. If the handle cannot be drawn back twice, the syringe cannot be refilled with fluid.

The elongate hollow syringe barrel, having a front end and an open rear, preferably has a retractable needle mounted retractably in a retracting structure disposed at the front end of the syringe barrel, biased for retraction in the backward axial direction. . The movable portion including a handle attached to the needle holding chamber performs the function of a conventional syringe plunger in the barrel. The front end portion of the needle holding chamber has a piston slidingly mounted in contact with the interior of the barrel. The movable portion is removed by a handle extending from the opening rear of the barrel. The rear end portion of the handle portion has a thumb cap for applying thumb force to the handle. An elongate hollow syringe barrel having a front end and an open back is suitably equipped with a retractable needle resiliently mounted in a retracting structure disposed at the front end of the syringe barrel, biased for retraction in the backward axial direction. The movable portion including a handle attached to the needle holding chamber performs the function of a conventional syringe plunger in the barrel. The front end portion of the needle holding chamber has a piston slidingly mounted in contact with the interior of the barrel. The movable portion is moved by a handle extending from the opening rear of the barrel. The rear end portion of the handle portion has a cap for applying thumb force to the handle. The needle holding chamber has a front openable sealed opening to receive the retracted needle in the needle holding chamber when the contracting mechanism is activated by the forward movement of the plunger after the fluid has been released during injection into the patient. The contraction of the needle into the needle chamber is triggered by the forward movement of the needle chamber relative to the contractile structure in response to the movement of the handle after the injection is complete.

A positive locking structure is disposed within the syringe barrel to prevent removal from the syringe barrel after single use and to limit movement of the needle holding chamber in the backward direction. The positive fastening structure has no effect on the one-time backward movement of the movable portion and the one-time forward movement of the movable portion to the maximum range of forward movement, but subsequent movement of the needle holding chamber in the backward direction is limited to maintain the chamber in the syringe barrel. .

In the first embodiment, the positive fastening structure is secured in the barrel in a fixed position. The fastening structure includes a barrel diameter contraction portion comprising a first stop portion, while the needle retaining chamber has a radially expanded section comprising a second stop portion, the second stop portion being deflected in a forward direction by pressing the handle. It may be pushed beyond one stop, but resists backward movement caused by the pulling of the handle. The first embodiment further comprises a handle portion removably attached to the needle holding chamber, which can be separated therefrom by a detachment force less than the force necessary to push the second stop over the first stop in the backward direction. The handle is suitably detachable from the needle holding chamber without breaking them by release of the separator.

The first embodiment preferably further comprises a catch on the front end portion which can be pushed in the forward direction beyond the first stop by pressing the handle before the second stop moves over the first stop. As long as the second stop does not move forward beyond the first stop, the handle may be withdrawn to fill the syringe. The catch on the front end portion of the needle holding chamber limits the amount of backward movement of the movable portion to form the maximum designed fill volume of the syringe. The catch is in contact with the first stop. However, when the plunger is pressed to perform an injection, the second stop on the back of the needle holding chamber or a predetermined intermediate portion on the needle holding chamber moves beyond the first stop, whereby the handle is pulled backwards. When provided, the above-described limiting feature causes the separation of the two-piece handle. After the handle is pushed forward with all stops exceeding the first stop in the barrel, the syringe is emptied and the contraction mechanism is actuated by continuous forward movement of the handle.

The second embodiment of the present invention has an elongated hollow syringe barrel suitable for having a retractable needle resiliently mounted in a retracting structure disposed at the front end of the syringe barrel, biased for retraction in the backward direction. A front end portion having a piston in sliding contact with the interior of the barrel, a rear end portion with a cap at the rear end for applying thumb force to the handle, and a needle at the front end portion of the handle for accommodating the retractable needle It has a movable handle in a syringe barrel with a holding chamber. In a second embodiment, the positive fastening structure is still placed in the syringe barrel. This limits the movement of the handle in the forward direction and prevents its removal from the syringe barrel after single use. However, the fastening structure moves relative to the barrel of the second embodiment.

The handle carries a fastening structure that can move in only one direction from a first position near the rear of the handle to a second portion closer to the front of the handle. The fastening structure is adapted to positively engage the syringe barrel and limiting movement of the needle holding chamber in the forward direction after the fastening structure is moved toward the first position. The needle holding chamber is suitably arranged immediately before the second position of the fastening structure. Preferably, the handle has a plurality of stepped teeth, and the positive fastening structure preferably has tabs inwardly angled with respect to the stepped teeth that allow the clip to move forward on the handle while preventing the handle from moving backwards. Do. The clip has at least one outwardly angled tip that engages the syringe barrel to prevent withdrawal of the handle. The tips simply slide along the surface of the handle because they are angled backwards, but the tips penetrate into the inner surface of the barrel to prevent backward movement. The clip is somewhat larger than a semicircle, and suitably surrounds some but not all of the stepped teeth of the rear end of the barrel.

The third embodiment of the present invention includes all other syringe features of the first and second embodiments except for the different positive fastening structures. In a third embodiment, an active fastening structure for limiting the movement of the handle in the backward direction is disposed in the syringe barrel in a fixed position relative to the barrel. More specifically, the structure is disposed inside the open rear of the barrel. The structure mounted inside the open rear of the barrel in a fixed position relative to the barrel may include one or more forward angles protected by the sliding collar supported by the handle in contact with the handle during the initial withdrawal of the handle for withdrawal of fluid into the barrel. It is suitable that it is an elastic clip provided with the formed tip part. This allows a one-time withdrawal of the handle in the backward direction from the initial forward position to the barrel without engaging the handle and the elastic tip. When the plunger is pressed in the forward direction, the slide collar moves forward out of contact with the tip of the elastic clip, and then the elastic clip engages with the handle to prevent its withdrawal. In the third embodiment, the rear end portion of the handle has a plurality of stepped teeth similar to the second embodiment in which a slide collar supported by the handle is disposed thereon. The sliding collar has an angled surface, which allows the plunger handle to move backwards with respect to the collar, but the collar captures the edge of the stepped teeth that move it away from the elastic clip and in the forward direction with the handle. It has a catch. The resilient clip is simply placed on the stepped tooth, not indirectly when the handle is moved forward, but as soon as the handle is moved back, the tooth digs into the handle to stop the predetermined backward movement of the handle. The stop face on the needle holding chamber contacts the collar and prevents further withdrawal of the handle after the handle is pulled back to the maximum range. The collar is captured in the barrel.

Although the present invention is most effective when combined with a retractable needle mounted on the contractile structure in front of the syringe, the present invention is primarily concerned with the issue of single use, and therefore, a syringe with a retractably mounted needle and a fixed Applicable to syringes with needles.

1 is a longitudinal sectional view of a first embodiment of the present invention having a needle uni chamber and a detachable hand, shown in a waiting position for a charging position;

2 is a cross-sectional view along line 2-2 of FIG. 1 of the handle and thumb cap of the first embodiment;

3 is a longitudinal sectional view of the first embodiment of FIG. 1 with the plunger pulled back to the stop in its full charging position;

4 is a longitudinal sectional view of the syringe of the previous figure after the handle has been pressed to the end of the injection position;

FIG. 5 is a longitudinal sectional view of the syringe of the previous figure illustrating handle detachment when the handle is pulled back without starting to retract from the position of FIG.

FIG. 5A is an enlarged longitudinal cross-sectional view of the middle portion of the first embodiment shown in FIG. 5 showing the plunger seal and the needle retaining structure taken to the position of FIG. 5 before shrinkage occurs; FIG.

5B shows the stop of the barrel as seen along line 5B-5B in FIG. 5;

FIG. 5C shows an alternative form of the stop of FIG. 5B showing that the stop is a series of one or more radial protrusions. FIG.

5d shows an alternative position of the stop of FIGS. 5b and 5c to assist in the stroke setting of the syringe.

FIG. 6 is a longitudinal sectional view of the syringe of the previous figure with the syringe barrel with the needle retracted into the needle holding chamber and the handle in its forward position with the thumb cap captured in the rear opening;

FIG. 7 is a longitudinal sectional view of FIG. 6 illustrating a method of detaching the handle from the needle holding chamber in the syringe of FIG. 6 when the handle is pulled back after the needle is retracted; FIG.

8 is a second aspect of the invention having a positive fastening structure comprising a retractably mounted needle, a needle retention chamber, a stepped handle having a plurality of stepped teeth and a clip shown in a first position near the rear of the handle Longitudinal cross-sectional view of an embodiment.

9 is a perspective view of an exemplary version of the clip as shown in FIGS. 8-14.

10 is a longitudinal cross-sectional view of the syringe of FIG. 8 with the handle pulled back to draw fluid into the syringe, whereby the clip has been moved to a second position closer to the front of the handle;

FIG. 11 is a longitudinal sectional view of the disposable shrink syringe of FIGS. 8 and 10 with the handle fully pushed forward to complete the injection.

12 is a longitudinal cross-sectional view of the syringe of FIG. 11 with the handle propelled to the maximum range beyond the full injection position, causing the needle to retract into the needle chamber.

Fig. 13 is a longitudinal sectional view of an alternative structure of the second embodiment of the present invention, in which the handle is detachably fixed to the rear of the needle holding chamber in a manner similar to the first embodiment, with the plunger at the complete end of the injection position;

FIG. 14 shows the syringe of FIG. 13 with the plunger further forwardly propelled from the position of FIG. 13 to retract the needle into the needle holding chamber.

FIG. 15 is a longitudinal cross-sectional view of a third embodiment showing different positive fastening structures having the same retractable needle and needle retention chamber as previous figures, but allowing the one-handed handle to be pulled back to fill the syringe;

16 is a perspective view of the elastic clip of FIG. 15 showing a plurality of good elastic tips.

17 is a longitudinal sectional view of the third embodiment of FIG. 15 after the handle is pulled back to a position corresponding to that of the embodiment of FIG.

18 is a longitudinal sectional view showing how the elastic clip is released to engage the handle as soon as the handle moves forward during the injection, thereby preventing any significant backward movement of the handle.

19 is a longitudinal cross-sectional view of the syringe of the third embodiment shown in FIG. 18 after the handle has been pushed forward to the injection completion position.

In the following description, like parts are referred to by the same reference numerals. The parts shown in the figures are preferably essentially circular or cylindrical.

The disposable shrinkable syringe of the first embodiment is disclosed in FIGS. 1 to 7 in conjunction with the variant of the shrinkable syringe shown in FIGS. 1 to 3 of US Pat. No. 65,632,733. Although details of preferred shrinkable syringes can be found in the cited references and other references listed in the background art herein, the main attributes thereof are briefly described herein in connection with the present invention. The present invention provides a positive fastening of the plunger handle to prevent reuse if the syringe is not withdrawn after its first use. The present invention is not limited to a particular retracting device or structure, and may be used after the injection is completed with other retractable needle devices, in particular those operated by forward pressing of the plunger handle. In the backward direction, there are a number of devices for withdrawing the needle into the opening of the plunger. By way of example, Toft US Pat. No. 5,407,436 or Pressly Sr. US Pat. No. 5,713,952 can be improved using the present invention. In the latter case, although the plunger handle is characterized to deter second use, it only functions if the syringe is actually retracted.

The disposable shrinkable syringe of the present invention is collectively referred to by reference numeral 10 in FIG. 1. The syringe 10 has an elongate hollow syringe barrel 12 having a first end portion 14 and an open rear end portion 16. The retractable needle 18 is resiliently mounted within the retracting structure 20, which includes an elongated needle holder 22 having a shoulder, the shoulder having an anterior end to prevent forward movement from the front. It stops at the opening in front of the part 14. A small portion of the needle holder extending forward beyond the barrel of FIG. 1 is shown in FIG. 1. The detachable retaining member 26 is a ring-shaped structure that is frictionally coupled, detachably along the interface of the retaining member 26 with the expansion head 30. The interface is oriented in the shrinking direction. Together with the head 30 of the needle holder 20, the retaining member 26 is directed against the inner sidewall 32 of the front portion 14 where they are held against the retraction force applied by the compressed spring 34. It is suitable to be fit. The spring 34 presses against one end resting on the ridge in front of the portion 14 and below the head 30 of the needle holder 22 without pressing against the removable retaining member 26. Has a rear end. The needle 18 is secured to the needle holder 22 by an adhesive 36.

The syringe is operated by a movable portion comprising a handle 38 removably attached to the needle holding chamber 40 by the detent connecting portion 42, the detent connecting portion being handled with the rear end of the needle holding chamber 40. It is suitable to form the snap engagement of the front portion 44 of 38. The handle 38 is suitably equipped with a core 76 having a thumb cap 70 and a guide groove 78, as shown in FIG. The gripping portion 80 operates in conjunction with the thumb cap 70 to allow one-handed operation. As shown in FIG. 7, the front 44 of the handle 38 removably mates with a single or multiple protrusion 48 at the rear end of the needle retention chamber 40 that includes the detent connection 42. It has a groove 46. The amount of force required to release the handle portion 38 from the portion 40 is less than the force required to pull the needle holding chamber past the stop in the barrel. The handle leaves the needle chamber in the barrel and separates from the needle chamber.

The movable parts 38, 40 together act as pistons in sliding contact with the interior of the barrel 12 and movable plungers mounted reciprocally in the barrel 12. The needle holding chamber 40 has a front end portion 50 having a piston seal 52 mounted thereon. The seal 52 is in sliding contact with the inner surface of the barrel 12, thereby forming a variable fluid chamber 56 under the front end 50 of the needle holding chamber 40. The needle holding chamber has an opening at its front end sealed with a removable plunger member or other seal 60 suitable for being held in the opening by frictional engagement.

The needle holding chamber 40 has a removable plunger 60 that slidably seals the opening into the chamber 58 and a holding space 58 for holding the retracted needle. The front end of the front end portion 50 comprises a tip 62, which is retained from the head 30 into the space 64 below the head 30 of the needle holder in the front end portion 14. To move and touch. This is achieved automatically by pressing the handle (moving part) from the complete "end of scanning position" shown in FIG. Further pressing the handle from the FIG. 4 position of the movable portion removes the ring-shaped retaining member, detaches the plug member 60, thereby opening the retaining space 58, and as shown in FIG. 6, the space 58. Release the needle 18 for shrinkage into. The structure described thus far provides a retractable needle syringe which prevents needle injection, and since the caps for the retraction and thumb are tightly received in the open rear end 16 of the barrel 12, the parts are not separated from each other and thus are not easily reused. Do not. The present invention makes it impossible to reach the needle or other part when the syringe is retracted, and further proceeds to prevent refilling when the syringe is not retracted.

Most notably, the inner surface 54 of the syringe barrel 12 restricts the movement of the needle chamber 40 in the backward direction and is radially inwardly projected contraction designed to prevent removal from the syringe barrel after single use. Or a positive fastening structure 66 comprising shrinkage portions. Needle holding chamber 40 preferably has an extended rear end 68 that cooperates with positive fastening structure 66 on the inside of the syringe barrel. The play is made to be pushed beyond the fastening structure 66 in the forward direction by the thumb force on the thumb cap 70. However, once the syringe handles 38, 40 have been pushed forward beyond the retracted portion 66 through the rear end 68 of the needle holding chamber 40, some attempt may be made to reverse this traversal. The reason is that the handle portion 38 is separated from the needle holding chamber 40 portion, as shown in Figs.

1 shows the position of the syringe in the recharge standby position. The handles 38 and 40 are pressed so that the rear end of the needle retainer chamber is in contact with what is referred to as a first stop 66 comprising a contraction of the barrel diameter in a fixed position inside the barrel. The rear end 68 of the needle holding chamber 40 suitably includes what is referred to as a second stop, which cooperates with the first stop to prevent further forward movement of the movable part, unless a significant force is applied. The second stop is suitably the radial extension of the cylindrical needle holding chamber most optimally arranged as shown in FIG. 1 behind the needle holding chamber. However, the radial extension can be moved forward from the rear end of the needle holding chamber depending on geometry requirements. The reason for the different location of the radial extension on the needle holding chamber is to change the filling stroke to form different filling volumes for different doses. The first and second stops 66, 68 comprise a positive fastening structure. Although the various fluid chambers 56 in the recharge standby position are very large, in fact, this is only a relatively small portion of the maximum syringe volume, and absolutely very small for a 1 cc or 1/2 cc syringe. As shown, the location of the stop 66 and the length and diameter of the holding chamber 40 and the barrel 12 determine the filling volume. The needle holding chamber is sized and positioned to receive the entire needle 18 so that no sharp tip is exposed after contraction.

3 shows the next step of the filling process, in which the user is free to pull the syringe handle backward until the catch 72 on the front end of the needle holding chamber 40 is captured on the first stop 66. I can pull it. This gives the user a tactile feeling to indicate that the syringe is fully filled with the injection.

4 illustrates the next step of syringe operation, where a needle is introduced into a patient (not shown) and the plunger is pressed down to the injection location endpoint. Here, the front end portion of the needle holding chamber 40 is such that the forward movement of the tip 62 sequentially begins to remove the plunger member 60 from the opening of the needle holding chamber 50, and the needle of the contracting structure 20. The holding member 26 is slid out of the head 30 of the holder 22. This is accomplished by pressing the thumb cap 70 until the thumb cap 70 is tightly received in the opening 74 in the extended rear end 16 of the barrel 12. This is the retracted needle position of FIG. 6, where the retractable needle has previously been retracted into the needle holding chamber together with the plunger member. The thumb cap 70 is housed in the opening. In this position, the needle is safely retracted and the handle is snugly inserted into the open rear of the syringe barrel to prevent reuse.

However, if the user refuses to retract the syringe after the position of FIG. 4 is reached, it cannot proceed to FIG. 6 and instead proceeds to FIG. 5. 5 shows that an attempt to remove the movable portion by pulling the handle portion 38 only causes the second stop 68 placed behind the needle holding chamber 40 to contact the first stop 66, Here, this shows that it can not proceed any further. The handle portion 38 is separated from the needle holding chamber 40 by simply releasing the detent connection 42 without leaving any access to the inner portion of the syringe. The groove 46 of the front 44 of the handle 38 separates the protrusion or protrusions 48. Minor distortion of the part can occur while it is released. As can be seen in FIGS. 4 and 5, there is an inadequate filling chamber in the variable chamber to reuse the syringe even when the handle 38 is reinserted into the rear of the barrel.

5A is an enlarged view of the center section of FIG. 5 between the break lines shown in FIG. Here, the catch 72 is shown in detail as an annular toothed radial projection on the front end portion 50. The back end portion 68 of the needle chamber 40 may have an extended diameter surface 82 having an edge that contacts the first stop 66. The detent projection 48 is shown at the rear end of the needle holding chamber 40 that fits into the groove shown in FIG. 5 of the removed handle portion 38. FIG. 5B is a cross-sectional view showing the first stop 66, which may be a continuous constriction around the inner diameter of the barrel 12. 5C shows that the stop 66 may be a plurality of extended regions or inward radial projections that contact and engage the rear end 68 of the needle retention chamber 40 to prevent its removal by the handle 38. Shows that. Similarly, when the fastening portion 66 is continuous, the rear end of the needle holding chamber 40 including the second fastening portion 68 is discontinuous. One or the other must be continuous so that there is no angular orientation of the needle holding chamber that allows the handle to be pulled out of the barrel.

5D may be modified as the straight rear end portion 68 ′ of FIG. 5D, sized to fit through the opening in the retraction caused by the stop 66. To illustrate. Alternatively, the radial expansion 69 on the outside of the needle holding chamber 40 may be arranged in different axial positions such that the positive fastening 66 functions as a contact acting thereon. The radial extension 69 may be considered a second stop in cooperation with the first stop 66 to limit the backward movement of the needle holding chamber. When the second stop 69 moves in the forward direction in response to the force applied to the cap 70, in exactly the same way as the extended rear end portion 68 of the needle holding chamber 40 of the previous figure, It is operable to be pushed through the opening in the constriction 66. When the user then wishes to pull back the handle, the radial extension 69 is in contact with the retraction 66 and exerts a pulling force greater than the force required to separate the handle 38 from the needle holding chamber 40. in need. This is a simple alternative way of providing different movements of the handle relative to the barrel, which can be useful in establishing the stroke of a particular syringe to deliver the desired dosage.

8-14 show a second embodiment of a disposable shrink syringe with the good shrink mechanism disclosed in the previous figures, to which the same reference numerals are applied. Deformations from the illustrated parts of the previous content will be indicated using prime symbols. The syringe of the second embodiment is collectively referred to by reference number 10 '. The retractable syringe 10 'has a retractably mounted needle 18 and a contraction structure 20 of the first embodiment which are exactly the same. It has a syringe barrel 12 ', which is different from that of the first embodiment in that it does not have an extended rear end portion 16 and does not have the same positive fastening structure. The syringe barrel 12 has a front end portion 14 and an open rear portion 84. The movable handle is reciprocally mounted in a syringe barrel 12 'comprising a needle holding chamber 40' attached to the handle portion 38 '. The front end portion 50 of the movable handle includes the same piston seal 52 and slidably removable plug member 60 as in the first embodiment already described. The rear end portion of the movable handle has a cap member 86 that includes a thumb cap at the rear end of the handle to apply thumb force to the handle. The needle holding chamber 40 'is attached or detachably attached to the handle portion 38' for manufacturing purposes only. If these two parts of the movable member are formed separately, they are suitably joined in a manner that cannot be separated by welding, gluing or other permanent fixation, or preferably molded as one movable handle.

The second embodiment differs from the first embodiment in that the positive fastening structure is the preferred metal clip 88 shown in FIG. The clip 88 has a tab 90 and a pair of fastening teeth 92 on the body 94. The tab 90 is bent slightly inwardly to cooperate with a plurality of stepped teeth 96 extending along the handle portion of the movable part behind the needle holding chamber 40 '.

8 illustrates the starting position of the disposable shrink syringe of the second embodiment. In the starting position, the movable handle is propelled completely within the syringe body to lightly touch the contraction mechanism 20 without causing contraction. This is easily done by the tactile sensation by the operator touching the plug member 60 in this case with respect to the needle holder head 30. The positive fastening structure 88 is supported by the handle portion 38 ′ and is movable from the first position 98 of FIG. 8 to the second position 100. This is accomplished simply and conveniently by pulling the movable handle against the syringe barrel. The positive fastening structure comprising the clip 88 is movable in only one direction from a first position near the rear of the handle to a second position closer to the front of the handle. The tip 92 is designed to engage the inner surface 102 of the barrel 12 'when an attempt is made to backward move the clip with the handle. Since the tip 82 is pointed backwards, they slide freely along the inner surface 102 as the clip moves forward in the barrel. Tab 92 rises over the edge of tooth 96 as the handle moves backward relative to clip 88, so that when the handle is pulled back, the stepped teeth simply slide against the clip, 8 may be disposed from the first position 98 of FIG. 8 to the second position 100 of FIG. 10. FIG. 10 illustrates the position of the handle relative to the clip 88 after the maximum amount of fluid is drawn through the needle 18 into the fluid chamber 56. The needle holding chamber 40 ′ is disposed just in front of the second position of the fastening structure 88. Thus, a clip containing the fastening structure is shown.

11 shows the position of the movable handle at the end of the injection position after all fluid has been withdrawn from the variable chamber 56. It can be seen that the inwardly angled tab 90 of the clip 88 captures the lower edge of the tooth 96 to move forward with the movable handles 38 ', 40'. The backward angled tip 92 simply slides along the inner surface of the syringe barrel 12 'without interfering with the forward movement of the movable handle.

FIG. 12 illustrates how the syringe 10 'of the second embodiment retracts its needle by simply pushing the thumb cap 86 and moving the movable handle from the injection position end of FIG. 11 to the contraction position of FIG. It can be seen that the retaining ring 26 has been removed from the head 30 of the needle holder 22 into the space 64 by the tip 62 and from the front end portion of the needle holding chamber 40 '. It can be seen that the spring loaded needle holder and the needle move backward when is removed and held there by the spring 34. The part is sized so that the entire needle, including the sharp tip, is drawn out into the barrel 12 '. A fastening structure is described that is disposed inside the barrel that has no effect on one backward movement and one forward movement of the movable handle. However, now the positive fastening structure 88 is disposed in the second position of FIG. 12. The predetermined reverse movement of the needle holding chamber in the backward direction is arranged such that the slide tip 92 now penetrates into the inner surface 102 of the barrel 12 ', thereby rearwardly ending the needle holding chamber 40'. Since the backward movement of the handle is prevented by the contact between the 104 and the bottom of the clip 88, the clip 88 is restricted. It can be seen that the handle 30 cannot be removed from the syringe after a single use because the clip cannot move in the backward direction and blocks the backward movement of the needle holding chamber 40 '. By comparing the positions of the clips of FIGS. 11 and 12, it can be appreciated that it does not matter whether the syringe is retracted or not, and the movable handle still cannot be removed. Thus, the handle is positively fastened into the syringe after one use. In addition, the filling volume can be adjusted according to the initial position of the clip 88 relative to the handle portion 38 ', as described in US Pat. Nos. 5,531,691 and 5,562,623 to Shonfeld et al. Mentioned in the prior art section.

13 and 14 correspond to FIGS. 11 and 12, respectively. These syringes 10 "differ from the syringes 10 'in FIGS. 11 and 12 only that the handle 38" is releasably connected to the needle holding chamber 40 "by a releasable connection 106. The rear end portion of the needle holding chamber 40 "has a groove 108 suitable for being a circumferential groove, and the front end of the handle portion 38" is the front end of the handle portion 38 "slanted into the groove 108. It is suitable to have a circumferential radial protrusion 110 in the form of a raised area secured to the part. The removable connection 106 forms a movable portion comprising a handle portion 38 " and a needle holding chamber 40 ", wherein the two-part structure facilitates forming and assembly, while allowing other releasable portions to be of a standard size. This allows you to change one of the parts while leaving it. For example, the handle portion can be made longer or shorter and can be used with the same needle holding chamber or the length can be changed while the needle holding chamber uses the standard handle portion 38 ". The reason is that different lengths of needles can be used, and there are other ways to change the stroke to change the maximum dose, but the length of the barrel can change, but the length of the barrel is not important, and that's why This is because the clip 88, which operates in exactly the same manner as described above with respect to Figs. 8 to 12, prevents the handle 38 "and the needle holding chamber 40" from being withdrawn after the initial injection. Withdrawal is prevented whether the contracting mechanism 20 is activated or not.

15-19 show a third embodiment of the invention, referred to as syringe 11. The syringe 11 is suitably the shrinkable syringe of FIGS. 1 to 7 with the specific exceptions listed below. Parts not shown in FIGS. 15 to 19 are considered to be the same as those of the first embodiment up to the rear end of the needle holding chamber. The rear end portion 112 of the barrel 12 has been modified to accommodate the elastic clip structure 114 shown in FIG. The barrel has a rear end that extends behind the grip 80, much like the rear 16 of the first embodiment. It still has an opening 74 for capturing and receiving a thumb cap 70 behind the handle 116, but with a contraction contact surface 118 just in front of the opening 74. The contact 118 forms a groove 120 around the extended rear end portion 112 of the barrel 12, where the spring clip 114 is received in a fixed position relative to the barrel. As can be seen, the spring clip 114 includes a structure disposed inside the barrel that limits the subsequent movement of the needle holding chamber in the backward direction after the initial use of the syringe.

The handle 116 extends behind the needle holding chamber 122 (FIG. 17) and is serrated along its length by a plurality of stepped teeth 124 similar to the stepped teeth 96 of the second embodiment. The slide in the form of a collar 126 is supported by a handle 116. The collar 126 includes a catch 128 that is adapted to capture the edge 130 of a predetermined stepped tooth 124. This may be a circular part or a split circular part to help mount the collar onto the handle. The thumb cap 70 may be installed and secured in place after the collar is installed on the shaft of the handle 116, or the handle may consist of two parts.

The elastic clip 114 suitably has a circular body 132 and a gap 134 that enable micro-compression of the circular body so that it can be inserted into the groove 120 past the contact 118. The elastic clip 114 has a plurality of elastic teeth 136, which are initially separated from the handle by the rear end portion of the slide collar 126, as shown in FIG. 15. This is the initial position of the handle corresponding to the starting position of FIG. 1 or 8. The micro retraction 138 in the handle 12 is the collar 126 when the handle 116 is pulled back to the position of FIG. 17 to draw fluid into the variable fluid chamber 156 (not shown) as in FIG. 3. To prevent it from moving backwards. Although the teeth and catches are somewhat exaggerated in the figures for illustration, the handle can be pulled back without difficulty to the injection standby position of FIG. 17. This represents the initial withdrawal of the handle 116 and the needle holding chamber 122. The rear end of the needle holding chamber 122 has a stop surface 140 that abuts against the collar 126 when the handle is fully drawn out, as shown in FIG. 17. The collar 126 still keeps the elastic teeth 136 out of contact with the handle of FIG. 17.

18 shows the handle 116 of the syringe 11 moving forward in response to the thumb force on the cap 70 from the position in FIG. 17 to the position in FIG. 18, and ultimately in the position shown in FIG. 19. At the start, show what happens. The catch 128 of the slide or collar 126 captures the edge 130 on the stepped tooth 124 so as to move forward in a direction away from the spring clip 114. This allows the elastic teeth 136 to climb over the stepped teeth 124 as the handle 116 moves forward. This continues until the position of FIG. 19 is reached.

19 illustrates the end point of a scanning position with the remaining portion corresponding to the position of FIG. 4 or 13. The front end portion of the needle chamber 50 similar to FIG. 1 reaches the contraction mechanism 20 in front of the syringe and fluid is expelled through the needle 18. The elastic teeth stay in the grooves 142 in the rear end portion of 116. However, also from the sharp angle of the tooth 136 relative to the stepped tooth 124, the position of FIG. 19 and FIG. 15 because the elastic tooth penetrates into a predetermined adjacent stepped tooth and engages the handle in the barrel. It should also be appreciated that it is not possible to pull the handle 116 back from a predetermined intermediate position between the positions of or the position of FIG. 18. Thus, the elastic clip 114 does not have any effect on one backward movement of the movable portion (handle and needle holding chamber) and one forward movement in the complete forward movement range, but subsequent movement of the needle holding chamber in the backward direction Provided is a positive fastening structure disposed inside the barrel in a fixed position to engage with the movable component, which is constrained to hold the chamber in the syringe barrel because the handle cannot be pulled back twice.

Finally, from the position of FIG. 19, the last propulsion of the thumb cap 70 in the forward direction after completion of the scanning position of FIG. 19 is contracted by the movement of the handle as shown in FIGS. 6, 12 and 14. Results in shrinkage action of the mold part. The needle is retracted into the needle holding chamber 122 and stored in the barrel. Thus, the plunger actuated contraction and contraction mechanism may be the same in all three embodiments with different positive fastening structures provided to limit the backward movement of the needle holding chamber.

In the best mode, the parts are formed from conventional injection moldable plastics, typically polypropylene. The piston seal is conventional and the clip is suitably metal.

Although exemplary embodiments of the present invention have been described herein with reference to the accompanying drawings, the present invention is not limited to these precise embodiments, and various other changes and modifications may be made without departing from the scope of the inventive concept. It should be understood that it can be performed by a skilled person.

Claims (35)

A disposable retractable syringe having a handle operated needle holding chamber that cannot be removed from a syringe barrel, An elongate hollow syringe barrel having a front end and an open rear; A retractable needle disposed at said front end of said syringe barrel and resiliently mounted within a retracting structure biased for retraction in a backward direction; The needle holding chamber having an openly sealed opening in the front for receiving the retracted needle, which is sealably and slidably mounted to move within the syringe barrel by a handle extending from the open rear of the barrel. A movable portion comprising a handle attached to the inside; A contraction portion of the needle in the needle retainer chamber triggered by a forward movement of the needle retainer chamber relative to the contractile structure in response to movement of the handle after completion of the injection; And A positive fastening structure disposed within the syringe barrel to limit movement of the needle holding chamber in the backward direction and to prevent removal from the syringe barrel after single use, The contracted syringe after use is safely stored in the needle holding chamber in the syringe barrel and cannot be easily removed by manipulation or withdrawal of the handle. The contractible syringe of claim 1, wherein the needle holding chamber is attached to the handle. The contractible syringe of claim 1, wherein the needle holding chamber is removably attached to the handle. 2. The structure of claim 1, wherein the positive fastening structure includes a structure disposed inside the barrel to engage the movable portion, wherein the structure moves in one direction backward and one direction forward until the movable portion moves forward as far as possible. The contracted syringe has no effect on, but subsequent movement of the needle holding chamber in the backward direction is limited to retaining the holding chamber in the syringe barrel. 5. A contractible syringe according to claim 4, wherein the structure disposed inside the barrel that restricts subsequent movement of the needle holding chamber in the backward direction remains in a fixed position relative to the barrel during use of the syringe. 6. The diameter of claim 5 wherein the structure disposed inside the barrel remaining in a fixed position relative to the barrel includes a contraction of a barrel diameter including a first stop and the needle holding chamber includes a second stop. And a second extending portion that can be pushed beyond the first stopping portion in the forward direction by pressing the handle, but resists movement in the backward direction caused by pulling the handle. 7. The handle of claim 6, wherein the handle is removably attached to the needle holding chamber and can be detached therefrom by a separation force less than the force necessary to push the second stop over the first stop in the backward direction, Therefore, the contractible syringe which can be separated leaving the needle holding chamber inside the barrel. 8. The contractible syringe of claim 7, wherein the handle can be separated from the needle holding chamber by rubbing the detent projection on the needle holding chamber from the groove on the handle. 9. The needle holding chamber of claim 8, wherein the needle holding chamber has a first end portion for carrying the catch, wherein the catch exceeds the first stop by pressing the handle before the second stop moves beyond the first stop. And pushed forward, the catch restricting the amount of backward movement of the movable portion to form a maximum designed fill volume of the syringe. 6. The retractable device as recited in claim 5, wherein said structure disposed inside said barrel that restricts subsequent movement of said needle holding chamber in a backward direction by remaining in a fixed position includes a structure mounted inside said open rear portion of said barrel. syringe. 6. The structure of claim 5, wherein the structure includes an elastic clip that positively engages with the handle after the handle is pushed forward to complete the injection, whereby the handle is once engaged with the clip. A shrink syringe for preventing subsequent withdrawal in this backward direction. 12. The device of claim 11, wherein the handle includes a thumb cap for forward pushing the handle, And the thumb cap is tightly received within the open rear of the barrel when the needle contraction is triggered by the plunger being fully pressed. 12. The handle of claim 11, wherein the handle extending behind the needle holding chamber is sawed along its length and has a slide on the handle, wherein the slide initially separates the elastic clip from the handle to dispense the syringe with liquid. And allow the plunger to be pulled backwards to fill and thereafter move forward when the handle is pressed to release the elastic clip for contact with the handle. 6. The structure of claim 5 wherein said structure disposed inside said barrel restricting subsequent movement of said needle retaining chamber in a backward direction contacts said handle and an elastic clip mounted inside said open rear portion of said barrel in a fixed position. A sliding portion, wherein the sliding portion maintains the elastic clip to be away from the handle when the handle is withdrawn in the backward direction, and moves forward with the handle when the handle is moved forward in the barrel. And a retractable syringe for releasing said elastic clip in contact with it. 5. A contractible syringe according to claim 4, wherein the structure inside the barrel that limits the subsequent movement of the needle holding chamber in the backward direction changes its position relative to the barrel while the syringe is in use. 16. The structure of claim 15, wherein the structure comprises an elastic clip that positively engages the handle after the handle is pushed forward to complete the injection, whereby after the handle is engaged by the clip, the subsequent Shrinkable syringe to prevent the handle from being pulled backwards. 16. The handle of claim 15, wherein the handle includes a thumb cap for forward pushing the handle, wherein the thumb cap is in the open rear portion of the barrel when the needle contraction is triggered by full depression of the plunger. Tightly housed shrink syringe. In a disposable syringe with a syringe barrel, there is provided a needle for injection of fluid extending from the front of the barrel and a movable handle mounted for limited reciprocating motion within the barrel and extending from the rear of the barrel, wherein the movable handle The rear of the handle having a front end portion slidably in contact with the interior of the barrel and having a piston in the barrel defining a variable fluid chamber for injection fluid, and a thumb cap for applying a thumb force to the handle. An end portion and within the barrel to limit the second backward movement of the handle after the first backward movement of the handle for filling the variable fluid chamber with the injection fluid and the first forward movement of the handle for injecting the fluid A disposable syringe comprising a positive fastening structure, The needle is a retractable needle that is mounted in a retractive structure in front of the needle with the needle extending to its non-retracted position and biased for retraction in the retracted direction, The front end portion of the handle is adapted to operate the contractile structure to retract the needle, and includes the piston and needle retainer chamber located behind the variable fluid chamber to receive the retracted needle, The needle holding chamber has a front end and a radially expanding section, The positive fastening structure is a stop disposed to limit the backward movement of the needle holding chamber into the range of the barrel by contacting the expanding section of the needle holding chamber, The handle is a one-piece handle having a rear end portion which is separated from the front end portion when the needle holding chamber is pulled beyond the stop by pulling the rear end portion of the handle, The syringe is a disposable syringe that cannot be reused even if the needle does not shrink after use. 19. The device of claim 18, wherein the stop is formed as a structure in the barrel that allows the front end portion of the handle and the needle holding chamber to be moved forward of the stop by pressing the thumb cap, When the needle holding chamber is pulled back, it generates a resistance force that is greater than the force required to contact the stop and cause detachment of the handle when moving in the backward direction, whereby the needle is held in the barrel and the Disposable syringe to prevent the second use of the syringe. 20. The disposable syringe of claim 19 wherein the handle can be separated from the needle holding chamber by rubbing the detent projection on the needle holding chamber from the groove on the handle. 20. The disposable syringe of claim 19 wherein the rear end portion of the handle and the needle retainer chamber are detachably connected by snap engagement. 20. The apparatus of claim 19, wherein the needle retainer chamber includes a catch near the front end that can be pushed forward beyond the stop by pushing the handle, wherein the catch is adapted to determine the maximum volume of the variable fluid chamber. A disposable syringe adapted to return to said stop when pulled back to form. A disposable shrinkable syringe with an operating handle that cannot be removed from the syringe barrel after a single use, wherein An elongate hollow syringe barrel having a front end and an open rear; A retractable needle disposed within the front end of the syringe barrel, the retractable needle being retractably mounted in a retracting structure biased in a backward direction for retraction; A front end having a piston in sliding contact with the interior of the barrel, a rear end portion having a cap for applying a thumb force to the handle, and the front end of the handle for receiving the retractable needle A movable handle in the syringe barrel having a needle holding chamber in the portion; And A positive fastening structure disposed within the syringe barrel to limit movement of the handle in the backward direction after a single use and to prevent removal from the syringe barrel, After use, the retractable needle is securely stored in the needle holding chamber in the syringe barrel and cannot be removed by withdrawal or manipulation of the plunger. The method of claim 23, wherein the handle supports the positive fastening structure that can move in only one direction from a first position close to the rear of the handle to a second position closer to the front of the handle, wherein the fastening structure is: And after the fastening structure is moved forward of the first position, positively engaging the syringe barrel to limit movement in the backward direction of the needle retainer chamber. 25. The disposable retractable syringe of claim 24, wherein said needle holding chamber is disposed immediately in front of said second position of said fastening structure. 26. The disposable retractable syringe of claim 25, wherein said needle is retracted by a thumb pressure acting on said cap behind said plunger after said plunger is fully pressed to achieve injection. 27. The method of claim 25, wherein the rear end portion of the handle has a plurality of stepped teeth, the positive fastening structure includes a clip having tabs angled inwardly relative to the stepped teeth, The portion allows the clip to be moved forward while preventing the clip from moving backward, the clip having at least one outwardly angled tip that engages the syringe barrel to prevent the handle from being pulled out. 28. The disposable retractable syringe of claim 27, wherein the clip circumscribes some of the stepped teeth on the rear end portion of the handle but not all of them. 24. The disposable shrink syringe of claim 23 wherein the positive fastening structure disposed within the syringe barrel includes a structure mounted in a fixed position relative to the barrel to limit movement of the handle in the backward direction. 30. The disposable shrink syringe of claim 29 wherein the structure is disposed inside the open rear portion of the barrel. 31. The handle of claim 30, wherein the handle includes a thumb cap for forward pushing the handle, wherein the thumb cap is intimately within the opening rear of the barrel when the needle contraction is triggered by the plunger being fully pressed. Disposable disposable syringes. 31. The structure of claim 30, wherein the structure mounted inside the open rear portion of the barrel in a fixed position relative to the barrel is an elastic clip, wherein the elastic clip is one time of the handle in a backward direction from an initial forward position relative to the barrel. And having at least one forward angled tip that prevents the slide collar supported by the handle from contacting the handle during the initial withdrawal of the handle to withdraw fluid into the barrel to allow withdrawal; thereafter the slide collar A forwardly moving out of contact with the spring clip when the plunger is pressed to perform an injection, the spring clip then engaging the handle to prevent its withdrawal. 33. The apparatus of claim 32, wherein the rear end portion of the handle has a plurality of stepped teeth on which a slide collar supported by the handle rests, wherein the slide collar enables the plunger handle to move backward with respect to the collar. And a sliding collar having an angled surface, wherein the sliding collar is moved forward with the handle by one of the teeth on the handle engaging the surface. As a disposable syringe, An elongate hollow syringe barrel having a front end portion and an open rear portion; A needle mounted to the front end portion of the barrel; A handle mounted to reciprocate in the barrel and having a front head portion having a piston in sliding contact with the inner surface of the barrel and a handle portion releasably connected to the head portion; And A fastening portion mounted in the barrel allowing the head portion to pass through the fastening portion when the head and handle portion are inserted into the open rear portion and a force is applied to the handle portion in the forward direction, The handle portion is separated from the head portion when the handle portion is pulled back after passing through the fastening portion in the forward direction, and the detachment of the handle portion from the head portion due to the resistance of the fastening portion without breaking the separating portion. Disposable syringe caused by the release. 35. The disposable syringe of claim 34 wherein said needle is a retractable needle resiliently mounted to said front end portion of said barrel.

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