FR2618075A1 - NON-REUSABLE HIGH SECURITY SYRINGE - Google Patents

Abstract

The present invention relates to a high security syringe. The aim of the invention is to make a syringe impeding a further reuse and enabling to hood the needle without any risk for the user. This aim is reached by means of a security syringe of the type comprising a pump body (1) provided with a needle (2) having a protection means (20) wherein slides a piston (3) of which the front end is provided with a sealing head (4) and the rear end is provided with a pusher (5), characterized in that the protection means (20) of the needle (2) is an integral part with the syringe but is movable in axial translation with respect to the piston (3) between a ''waiting'' position wherein the needle is uncovered, and a ''security'' position wherein the needle (2) of the syringe to be disposed is masked. The syringe of the invention is particularly intended to be used by the medical and paramedical staff.

Description

"High security syringe not reusable"
The invention relates to a new type of syringe, and more particularly a high-security syringe preventing subsequent reuse and making it possible to cap the needle without risk for the user.

 Indeed, usually, after having taken a sample or an injection on a patient, the carer re-hair the needle using a protective cap of small diameter, or this operation can be missed from time to time, and the caregiver is then pricked with the needle which has just been used for care.

Faced with the resurgence of infectious diseases such as AIDS or HEPATITIS B, contagious by blood, the medical professions are therefore particularly exposed to the risks of contagion by bites.

 Faced with this danger, new regulations have been put in place, obliging the nursing staff to wear gloves, but this does not absolutely protect them against these risks. In addition, medical personnel are required to carry out indirect recapping of needles by means of rubber pliers, but this is an inconvenient operation and therefore seldom used. Most often, the staff throw the unprotected needles directly into cardboard receptacles provided for this purpose, and it is then the hospital workers who are at risk of pricking themselves by transferring these cartons to the incinerator.

 Another problem which arises is that of the reuse of syringes. Often, drug addicts reuse a syringe several times, which increases the risk of contagion. In addition, certain epidemiological data seem to demonstrate the great importance of the multiple use of syringes as a vector of contagion in developing countries, especially since the parenteral route is the main mode of care in these countries. It is therefore highly desirable to make non-reusable syringes.

 The first object of the invention is therefore to produce a high-security syringe allowing the needles to be recapped, without risks of injections and contamination for the user.

 Another object of the invention is to provide a non-reusable high security syringe.

 Another object of the invention is to obtain a syringe which is easy to manufacture and of low additional cost compared to a conventional syringe.

 These objectives and others which will appear subsequently are achieved using a safety syringe, of the type comprising a pump body provided with a needle provided with a protection means, in which a piston slides. the front end of which is provided with a sealing head and the rear end of a plunger, characterized in that the needle protection means are integral with the syringe but are movable in axial translation relative to the piston between , a "waiting" position where the needle is uncovered, and a "safety" position where the needle of the disposable syringe is hidden.

The characteristics and advantages of the invention will emerge more clearly from the description which follows concerning two embodiments of the invention given by way of nonlimiting example and illustrated in the attached drawings in which
FIG. 1 is a view in longitudinal section of the syringe according to the invention, before use,
FIG. 2 is a view in longitudinal section of the syringe according to FIG. 1, ready for use,
FIG. 3 is a view in longitudinal section of the syringe according to FIG. 1, after use,
FIG. 4 is a cross-sectional view of the syringe of FIG # ure 1, along line 4-4,
FIG. 5 is a cross-sectional view of the syringe according to FIG. 1, along the line 5-5,
FIG. 6 is a view in longitudinal section of another embodiment of the syringe according to the invention, before use,
FIG. 7 is a view in longitudinal section of the syringe according to FIG. 6, ready for injection,
FIG. 8 is a view in longitudinal section of the syringe according to FIG. 6 at the end of injection,
- Figure 9 is a longitudinal sectional view of the syringe according to Figure 6, ready to throw.

 As illustrated in FIGS. 1 and 6, the syringe according to the invention conventionally comprises a pump body 1 provided with a needle 2, and in which a piston slides. 3, the front end of which is provided with a sealing head 4.

 Two particular embodiments will now be described in detail.

 As illustrated in FIG. 1, the pump body 1 is a hollow cylinder partially closed at its anterior end by an annular shoulder 6 and a conical base 7. The needle 2 is provided with a conical, hollow pavilion 8, the dimensions of which are such that it fits perfectly on the base 7. The rear end of the pump body 1 is open and carries on its periphery, and perpendicularly, two fins 9 which facilitate gripping by the user.

 The piston 3 has a cruciform cross section (see Figure 5), and its rear end is provided with a pusher 5 consisting of a thin disc. The sealing head 4 consists of a thin rubber cylinder provided with a peripheral annular groove 10. This disc 4 is secured by one of its faces to the piston 3 and its other face is conical, so as to correspond with the slight conicity of the annular shoulder 6. In addition, the diameter of this sealing head 4 is equal to the internal diameter of the pump body 1, which ensures perfect sealing during the axial movement of the piston 3 in the pump body 1.

 In order to avoid pinhole contamination with the needle 2, a means 20 for protecting the needle is provided. This protection means consists of a cylindrical sheath 20 whose length is at least equal to the length of the needle 2. This sheath is coaxial with the pump body 1, and movable in translation relative to the latter and by ratio -to the piston 3. The internal diameter of said sheath is very slightly greater than the external diameter of the pump body 1, so that it can slide easily around it.

 The sheath 20 slides between a "waiting" position in which it covers the pump body 1 and in which the needle 2 is uncovered and usable for a withdrawal or an injection, and a "safety" position in which the needle 2 is hidden. In other words, in the first position, the user can reach the needle and use the syringe in a conventional manner while in the second position he can no longer reach needle 2, nor risk pricking himself, since that -this is surrounded by the sheath 20.

 The front end of said sheath is conical and defines a circular opening 21 whose diameter is slightly greater than that of the pin 8 of the needle 2 but less than the usual size of the end of a finger. Thus, when the sheath 20 is in the "waiting" position, the caregiver can push said horn 8 onto the base 7 of the pump body 1 without being hampered by the sheath, and vice versa when said sheath 20 is in the " security ", a third party cannot run their finger through hole 21 and attempt to prick themselves.

 There is also provided on the periphery of the anterior end of the sheath 20 at the intersection of the conical part and the cylindrical part, at least one grasping ear 22. Preferably, the syringe is produced with two ears 22 symmetrically distributed relative to the axis of the sheath and perpendicular to this sheath, these ears being of semi-circular shape. These gripping ears 22 allow the user to more easily hold the sheath 20 to make it undergo a translational movement.

 When the sheath 20 has been brought into the "safety" position, it is desirable that a third party cannot slide the sheath a second time into the "waiting" position, and risks being pricked. For this purpose, a blocking device has been provided for immobilizing said sleeve 20 on the pump body 1 in the "safety" position. This blocking device is made up of a non-reversible rack, that is to say that the periphery of the anterior end of the pump body 1 is provided with serrated notches or scales 23 oriented towards the front, while the internal surface of the rear end of the sleeve 20 is provided with notches 24 identical to the notches 23, but oriented towards the rear. Thus, it is possible to slide the sleeve 20 for the first time. the "waiting" position towards the "safety" position illustrated in FIG. 3, because the scales 24 slide on the scales 23, but it is however impossible to then bring the sheath 20 back to its initial position, because then the top notches 24 are embedded in the hollow between two corresponding notches 23, thus blocking the device.

 In addition, a plug 25 is fixed by a fine fastener on the periphery of the sheath 20 at equal distance between the two ears 22 (see Figure 4). The plug 25 and the sheath 20 are molded in one piece. The diameter of this plug corresponds to the diameter of the opening 21 and the user has this plug 25 in this opening 21 when the injection is finished and the sheath 20 is in the "safety" position. This plug 25 makes it possible to prevent a drop of contaminated blood possibly remaining at the end of the needle 2 from escaping from the sheath 20.

 According to another alternative embodiment, shown in FIGS. 8 and 9, the rear end of the piston 3 does not include a cylindrical plunger 5 but # a projection 50 for fixing a removable plug 51.

The diameter of this plug 51 corresponding to the diameter of the opening 21. The plug 51, 25 could also be replaced by a cap. This plug 51, 25 or cap serves as a sort of pusher when they are fixed on the projection 50.

 Preferably, the sheath 20 will be made of transparent plastic so that we can see through the measurement graduations written on the pump body 1.

 In order to avoid subsequent reuse of the syringe, it is fitted with a rack device. The piston 3 is provided on its periphery with at least one main rack 30.

As illustrated in FIG. 5, this rack device is in fact made up of four main racks 30 arranged in the four corners of the cruciform piston 3. These racks 30 are strips of triangular cross section, of a length less than the distance between the sealing head 4 and the pusher 5, in order to provide a control clearance 31. The length of this control clearance 31 is approximately 1/6 of the total length of the rack 30. The racks 30 are in contact by two of the faces of the triangle with the right-angle parts of the cruciform piston, and the third face of the triangle directed towards the outside of the piston 3 is provided with notches 38 oriented towards the rear of the syringe.

 The internal surface of the rear end of the pump body 1 is provided with notches 32 also oriented towards the rear.

 A secondary rack 33 is arranged longitudinally between the pump body 1 and the piston 3. This secondary rack is in the form of a hollow cylinder, and can optionally be provided with a slot 35 extending over its entire length, its corresponding external diameter to the internal diameter of the pump body and its internal diameter to the external diameter of the piston 3.

This secondary rack 33 is provided with notches 36 on its external surface and notches 37 on its internal face.

These notches 36 and 37 or scales are oriented towards the front of the syringe. The notches 36 do not extend over the entire length of the secondary rack 33, but from its rear end to a short distance from its front end so as to provide a pad 39 having a smooth surface. The length of the secondary rack 33 is approximately one third of the main rack 30.

 The operation of the syringe will now be explained in detail.

 This syringe can of course be used indifferently for a sample or an injection.

 When the nurse uses this syringe, she checks that the piston 3 is at the bottom of the pump body 1, we are then in the "before use" position, then she pulls lightly on the piston 3, in order to see if any blood arrives in the pump body and therefore whether or not the needle is in a vessel. It is then in the position shown in FIG. 1. The main racks 30 are arranged on the piston 3 so as to extend from the sealing head 4 to a short distance from the pusher 5. This short distance corresponds to the control clearance 31. Furthermore, the secondary rack 33 is placed between the piston 3 and the pump body 1, and in contact with the sealing head 4.

 When the syringe is used (see Figure 2), the nurse pulls on the plunger 3 so as to pump the blood inside the pump body 1. During this movement, the main rack 30 remains in place on the plunger 3, and the secondary rack 33 moves transversely relative to the pump body, but remains however in its initial position relative to the piston 3. The notches 36 of the external face of the secondary rack 33 can slide freely on the notches 32 of the pump body 1. This movement is stopped when the secondary rack slightly protrudes out of the pump body 1. This translational movement is illustrated in FIG. 2. In the case of syringes delivered already filled (type vaccine syringe) there is directly in this position (Figure 2) and the secondary rack 33 can be deleted. In this case, the notches 32 of the rear end of the pump body 1 are oriented towards the front and the dimensions of the main rack 3-0 are larger so that the notches 38 come into contact with the notches 32 .

 When the sample is taken, the nurse pushes back the piston 3 so as to evacuate the blood contained in the pump body 1 in a container provided for this purpose, such as a test tube for example.

During this movement, the secondary rack 33 remains locked in its previous position, since these notches 36 come to lock on the notches 32 of the pump body 1. On the other hand, the main rack 30 can slide freely towards the front of the syringe. At a given moment the rear end of the main rack 30 will be at the same level as the rear end of the secondary rack 33, and we will continue to push the piston 3 until the head 4 comes in contact with the annular shoulder 6. This is possible because the rack 30 slides freely on the piston 3. The clearance 31 will then be located at the front between the sealing head 4 and the rack 30. At this time, the nurse pushes the sheath 20 back into the safety position and sets up the plug 25, 51 as described above.

 A second embodiment of the syringe will now be described.

 As illustrated in FIG. 6, the syringe comprises a pump body 1 inside which slides a piston 3 provided with a sealing head 4 whose structure is identical to that which has been described previously. This body 1 is a hollow cylinder, the front end of which is bordered by an annular shoulder 42 defining a circular opening 47. The dimensions of this opening are there too, less than the usual size of a finger. The sealing head 4 is provided on its front face with a circular locking end 40 and whose diameter is slightly less than that of said head 4. On the other hand, the needle 2 is fixed in a plug 41 in rubber, circular retained at the front of the pump body by the annular shoulder 42 provided at the anterior end of said body 1. This plug 41 has a peripheral annular groove 48, bordered by two lateral lips 60. At these lips 60, the diameter of the plug 41 is equal to the internal diameter of the pump body 1. This plug 41 also has a circular projection 49, directed outwards, and the diameter of which is equal to the diameter of the opening 47.

The needle 2 passes through this plug 41 right through, and opens into a cavity 43, located on the rear face of said plug, and having a shape complementary to the locking end piece 40 of the sealing head 4.

According to an alternative embodiment (not shown) the projection 49 may have a shape identical to the base 7 and be pierced with an orifice opening into the cavity 43.

Thus, any type of needle (intravenous, intramuscular, subcutaneous) provided with a pin 8 can be adapted there. The cap is coaxial with the pump body 1.

The locking end piece 40 has at its free end a snap ring 45, and the cavity 43 of the plug 41 is provided with an internal groove 46. Thus, the profile of the locking end piece 40 corresponds to the profile of the cavity -43. Preferably, the plug 41, the sealing head 4 and its locking end piece 40 are made of rubber.

 The rear end of the piston 3 is provided with a projection 50 for fixing a removable plug. 51, the diameter of this plug 51 corresponding to the opening 47 of the front end of the pump body. This plug 51 then serves as a pusher 5. This plug 51 could also be replaced by the plug 25 described above but whose dimensions would correspond to the opening 47.

 The operation of this syringe will now be described.

 Before use, the piston 3 is not fully depressed to the bottom of the pump body 1 (see Figure 6). To carry out the blood sample, the nurse pulls on the piston 3 so as to pump the blood inside the pump body 1. The piston 3 therefore moves coaxially with said pump body. We are then in the position illustrated in FIG. 7. Once the sample has been taken, the nurse pushes back the piston 3 so as to empty the blood contained in the pump body, in a container provided for this purpose. At this time, the nurse pushes the piston 3 to the bottom of the pump body 1, and therefore, the locking end piece 40 of the sealing head 4 snaps into the cavity 43 thanks to the internal groove 46 and the snap ring 45. This is illustrated in FIG. 8.

 Before throwing away the syringe, and in order to camouflage the needle 2, the nurse pulls a second time on the piston 3, which has the effect of driving the plug 41 and the needle 2 linked to the sealing head 4.

Thus, the needle 2 is surrounded by the pump body 1 which therefore serves as a protective means 20. Then, the nurse can remove the plug 51 fixed on the piston 3, and place it in the opening 47 , which prevents a drop of blood remaining at the end of the needle 2 from escaping from the protection means 20 (see FIG. 9).

 This syringe can of course also be used for an injection.

 Of course, the invention is not limited to the example of embodiment described above for which we can provide other alternative embodiments without departing from the scope of the invention.

Claims (12)

 1) Safety syringe, of the type comprising a pump body (1) provided with a needle (2) provided with a protective means (20), in which slides a piston (3) whose front end is provided a sealing head (4) and the rear end of a plunger (5), characterized in that the protective means (20) of the needle (2) is integral with the syringe but is movable in axial translation with respect to the piston (3) between a "waiting" position where the needle is uncovered, and a "safety" position where the needle (2) of the disposable syringe is hidden.  2) Safety syringe according to claim 1, characterized in that said protective means (20) consists of a sliding sleeve coaxial with the pump body (1), the length of this sleeve (20) being at least equal to the length of the needle (2).  3) Safety syringe according to claim 2, characterized in that the front end of said sheath (20) is conical and defines a circular opening (21) whose diameter is slightly greater than that of the horn (8) of the needle (2) but smaller than the usual size of the end of a finger.  4) Safety syringe according to claims 2 or 3, characterized in that the periphery of the front end of the sheath (20) is provided with at least one gripping lug (22).  5) Safety syringe according to claim 2, 3 or 4, characterized in that said sleeve (20) is immobilized on the pump body (1) in the "safety" position by means of a blocking device ( 23, 24).  6) Safety syringe according to claim 5, characterized in that the blocking device (23, 24) consists of a non-reversible rack, the periphery of the front end of the pump body (1) being provided with notches (23) oriented towards the front, while the internal surface of the rear end of the sheath (20) is provided with notches (24) oriented towards the rear.  7) Safety syringe according to one of claims 2 to 6, characterized in that the piston (3) is provided on its periphery with at least one main rack (30) whose notches (38) are oriented towards rear this rack (30) being of a length less than the distance between the pusher (5) and the sealing head (4) in order to provide a clearance (31), the internal surface of the rear end of the pump body being provided with notches (32) also oriented towards the rear, and in that at least one secondary rack (33) in the form of a hollow cylinder is disposed longitudinally between the piston (3) and the pump body ( 1), this rack having on its internal and external surface, notches (37, 36) oriented towards the front.  8) Safety syringe according to one of claims 2 to 6, characterized in that the piston 3 is provided on its periphery with at least one main rack (30) whose notches (38) are oriented towards the rear, -this rack (30) being of a length less than the distance between the pusher (5) and the sealing head (4) in order to provide a control clearance (31), the internal surface of the rear end of the pump body (1) being provided with forward-facing notches (32), the dimensions of the rack (30) being such that the notches (38) come into contact with the notches (32).  9) Safety syringe according to claim 1, characterized in that the front face of the sealing head (4) of the piston (3) is provided with a locking end piece (40) whose diameter is slightly less than that of said head (4), the needle being fixed on a plug (41) retained at the front of the pump body by an annular shoulder (42) provided at the anterior end of said body, this shoulder (42) defining a circular opening (47) whose diameter is less than the usual size of a finger, said plug (41) comprising a cavity (43) having a shape complementary to the locking end piece (40) of the sealing head ( 4) of the piston, this same plug also being coaxial with the pump body and movable in translation inside the latter which acts as a protective means (20).  10) Safety syringe according to claim 9, characterized in that the locking end piece (40) comprises a snap ring (45), and the cavity (43) of the plug <41) is also provided with a groove internal (46) whose profile corresponds to that of the ring (45).  11) Safety # syringe according to one of claims 3 to 10, characterized in that the rear end of the piston (3) is provided with a projection (50) for fixing a removable plug (51), the diameter of said plug (51) corresponding to the diameter of the opening (21, 47) of the front end of the protection means (20).  12) Safety syringe according to one of claims 3 to 10, characterized in that the protective means (20) is provided with a plug (25) molded in one piece, this plug (25) being fixed by a fine clip on the suburbs. of said means (20) and its diameter corresponding to the diameter of the opening (21, 47) of the anterior end of the protection means (20).