FR2971424A1 - SAFETY SYRINGE - Google Patents

Abstract

The invention relates to a secure disposable injection device comprising a syringe body (1), a protective case (7) and an intermediate connecting piece between the syringe (1) and the protective case (7). , comprising a ring (22) adapted to be positioned in the protective case (7), and at least one radially deformable longitudinal flexible blade (29, 30), said ring comprising means for locking (27) the collar (1b) of the syringe (1), in a position where each flexible blade (29, 30) extends along the syringe (1), in a radially expanded state by said syringe.

Description

The invention relates to a secure disposable injection device. For obvious safety reasons, current disposable injection devices are commonly equipped with a protection device after use of the injection needle. In the usual way, such injection devices comprise a syringe body comprising a container carrying an injection needle and provided with a piston actuated by a piston rod equipped with a push button, and a protection device comprising: A protective case adapted so that said protective case and the syringe body are able to slide relative to one another between an injection position in which the injection needle extends at least partially in the extension of the protective case, and a position of protection after use in which the injection needle is fully housed in the protective case, - locking means adapted to present a locked state of maintaining the syringe body and the protective case in their injection position, and to switch to an unlocked state able to allow, at the end of the piston stroke inside the receptacle the relative sliding of the syringe body and the protective case towards their protective position after use; and elastic means arranged to be held compressed between the syringe body and the protective case in their position. injection, and to relax and cause relative sliding to the protection position after use, in the unlocked state of the locking means. On the basis of this principle, a first technique consisted in designing injection devices such as in particular described in the patent applications WO 91.13634, WO 93.23089, WO 93.25254, EP 30446.551 and EP 307.367, comprising syringes specifically created to equip the said injection devices. This solution, however, is expensive because it requires in particular the production of syringes at a cost significantly higher than conventional syringes, such as glass syringes currently produced in large series and therefore at a very low cost.

In order to overcome this drawback, another technique has consisted in making secure disposable injection devices of the type especially described in patent EP 1218047, incorporating syringes of conventional design, such as glass syringes.

The present invention also aims at an injection device adapted to integrate a syringe of conventional type, and has the main objective of producing a simplified design injection device and therefore a lower overall cost compared to the devices of FIG. injection, as described in particular in EP 1218047.

For this purpose, the invention is directed to a secure single-use injection device, comprising in combination: a syringe carrying an injection needle and provided with a posterior collar, said syringe housing a piston capable of sliding between a retracted position and an advanced end position, associated with a piston rod with a push button, - a protective case with digital support members, adapted so that the syringe is able to slide to the inside of said protective case between an injection position in which the injection needle extends at least partially in the extension of the protective case, and a protective position after use in which the needle of injection is fully housed in the protective case, - and an intermediate piece of connection between the syringe and the protective case, comprising a ring adapted to be positioned in the protective case, and at least a longitudinal flexible blade deformable radially, said ring having means for locking the collar of the syringe, in a position where each flexible blade extends along said syringe, in a radially expanded state by said syringe, - the ring and the protective case comprising front stop members of the ends of resilient means disposed between 301es said stop members and adapted so that each flexible blade extends inside and in the extension of said elastic means, la ring and the protective case comprising means of locking relative relative to translation, said posterior, adapted to: - ensure a relative locking in translation of said ring and said protective case in an injection position in which the means elastics are held in a compressed state between the abutment members of said ring and said protective case, - switch to a state deveve rriillé able to allow, at the end of stroke of the piston inside the syringe, the sliding of the syringe and the ring to the protective position after use, - and at least one flexible blade and the protective case 10comportant relative locking means in translation said prior, adapted to ensure a relative locking in translation of said protective case and each of said flexible blades in its radially expanded state, in the protective position after use. (It should be noted that in the present application, terms such as anterior or posterior are used with reference to the end of the injection device having the injection needle, the former term, for example, denoting a portion or a face of an element oriented towards this reference or the closest to it). The injection device according to the invention is therefore, in the first place, designed to integrate a syringe of a conventional type which may therefore consist of any usual syringe made of glass or plastic material. Moreover, this injection device comprises means protection after use of the syringe consisting of only two elements of very simple design and therefore a very low cost: a protective case and an intermediate connecting piece between the syringe and the protective case. The assembly operations of this injection device are furthermore simplified to the extreme since this assembly simply requires: positioning the elastic means in the protective case, and introducing the intermediate piece of connection into the protective case, until the relative locking in translation of the ring and said protective case in the injection position in which the elastic means are held in a compressed state between the stop members of said ring and of said protective case, - then introduce the syringe into the protective case until a locking of the collar of said syringe by the locking means of the ring. It should also be noted that: this assembly is authorized thanks to the possibility of radial deformation of the flexible blades, which allows the prior blocking members of said flexible blades to pass through the corresponding anterior locking members of the casing of protection - this faculty of radial deformation of the flexible blades 10is then removed during the introduction of the syringe into the protective case, so that, after injection, the relative anterior locking means in translation ensure an irreversible locking in translation of the protective case and each of said flexible blades in its radially expanded state. Furthermore, each flexible blade of the intermediate connecting piece can be held manually deformed for introduction into the protective case. However, to facilitate this introduction, and advantageously according to the invention, each flexible blade of the intermediate part 20binding has a natural shape in which it has a longitudinal axis converging in the direction of the axis of revolution of the ring. According to another advantageous embodiment of the invention, the ring of the intermediate connecting piece comprises a radially deformable posterior portion carrying the rear locking means 25 in translation, arranged to be deformed by the piston of the piston rod at the end. piston stroke, so as to switch said rear locking means to their unlocked state. In addition, in order to ensure a relative indexing and locking in rotation of each flexible blade of the intermediate connecting piece and the protective case, the latter is advantageously shaped so as to define, for each flexible blade, a groove section adapted to accommodate the said flexible blade, in which are formed the means for preventing relative locking in translation of said protective case.

Furthermore, the protective case advantageously comprises, according to the invention, two longitudinal sections of different diameters separated by a shoulder: - an anterior section adapted to guide the syringe 51a and each flexible blade, when sliding to the position of protection after use, - a rear section of conjugated diameter of that of the ring, adapted to form a housing for the elastic means extending between the shoulder and said ring. In addition, the protective case then advantageously comprises an anterior section of conjugate inner section of the external section of the syringe, having, for each flexible blade, a longitudinal outer boss defining the guide groove of said flexible blade . According to another advantageous embodiment of the invention, the translation-related relative locking members comprise: a transverse rib provided with radial locking end faces, formed on each flexible blade, and for each flexible blade, a light of 20conjugated form of the transverse rib of said flexible blade, formed in the peripheral wall of the protective case, and delimited by an elastically radially deformable anterior tab, access to said light. Other features, objects and advantages of the invention will be described in the following detailed description with reference to the accompanying drawings which represent by way of non-limiting example a preferred embodiment. In these drawings: FIG. 1 is a perspective view of an injection device according to the invention, FIG. 2 is a cross section through a plane A of this injection device, FIG. is a perspective view of the intermediate piece of this injection device, - Figure 4 is a longitudinal section through an axial plane of the injection device shown before use, - and Figure 5 is a longitudinal section through a plane axial representative of this injection device after injection, the secure disposable injection device shown in the figures consists of an injection device comprising a syringe and a protective device after use of said syringe. Firstly, the syringe consists of a pre-filled syringe 1 of traditional type, such as for example made of glass, 10comportant, conventionally, a base la in which is sealed an injection needle 2, and a collar 1 b at its posterior end. This syringe 1 also comprises, in a conventional manner, a cap 3 for protecting the injection needle 2, adapted to be mounted in a sealed manner on the base 1a of said syringe. It also comprises, in a conventional manner, a piston 4 adapted to slide in a sealed manner inside the syringe 1 between a retracted position in which it delimits a chamber filled with a dose of liquid to be injected, and an advanced position of limit switch. This piston 4 is furthermore pierced with a blind bore into which the front end section 5a of a piston rod 5 with a push button 6 at its rear end engages. According to the invention, this push button 6 is in the form of a cup having a slice 6a oblique profile. Second, the protective device after use of the pre-filled syringe 1 consists of two elements adapted to be pre-assembled before the introduction of said syringe into said protective device. The first of these elements consists of a protective case 7 comprising, in one piece, two longitudinal sections 8 and 9 of different diameters separated by a radial shoulder 10, at which the said protective case comprises external organs d 11. The anterior portion 8 is adapted to guide the syringe 1 during its sliding to the protective position after use, and to house the injection needle 2 in this protective position after use. This anterior section 8 has, for this purpose, a conjugated internal diameter of the diameter of the syringe 1. In addition, this anterior section 8 comprises, over the greater part of its length, from the shoulder 10, two longitudinal projections 12 , 13 diametrically opposed each delimiting a groove 14 of substantially rectangular cross section. At their rear end portion, each of the bosses 12, 13 comprises a deformable tongue, such as 15, 10 delimited by a U-shaped cutout 16 formed in the front wall of said boss, this tab 15 being separated from the shoulder 10 by a slot 17 formed in said front wall in the continuity of said tongue. In addition, each of the tongues 15 has, at the level of its posterior free end, a transverse rib 18 projecting inside the groove 14 and having an oblique front face 18a forming a ramp and a rearward anti-back face 18b substantially radial. The posterior section 9 of the protective case 7 has a diameter greater than that of the front section 8, and comprises two transverse slots such as 19 that are substantially rectangular, arranged diametrically opposite at a small distance from the posterior end of the case. said posterior section. The second element of the protective device after use of the pre-filled syringe 1 consists of an intermediate piece 20 connecting said syringe and the protective case 7. As shown in particular in Figure 3, this intermediate piece 20 comprises, in the first place, a ring 21 composed of: - a cylindrical sleeve 22 of diameter adapted to be introduced into the rear section of the protective case 7, - and an anterior front wall 23 defining a circular orifice 24 of conjugated diameter of the outer diameter of the syringe 1.

In addition, the cylindrical sleeve 22 of this ring 21 is extended posteriorly by two tabs such as diametrically opposite having the shape of cylindrical sectors. Each of these lugs 25 has, in the first place, a rear sloping section 25a complementary to that of the slice 6a of the pusher 6 of the piston rod 5. Each of these lugs 25 also comprises substantially mid-length , a transverse external rib 26 adapted to be housed in one of the slots 19 of the protective case 7. Each of these ribs 26 has, in addition, an oblique front face 26a forming a ramp and a rear locking face 26b substantially radial. The cylindrical sleeve 22 further comprises, substantially mid-length, two internal ribs such as diametrically opposed, locking the flange 1b of the syringe 1 between said ribs and the annular front wall 23 of the ring 21. In addition, the peripheral wall of this cylindrical sleeve 22 is pierced, downstream of each of the inner ribs 27, a light such as 28 allowing the release of the undercut. The intermediate piece 20 further comprises, in the extension of the annular front wall 23 of the ring 21, two diametrically opposed flexible blades 29, 30. Each of these flexible blades 29, 30 has the shape of a cylindrical sector of a fictitious cylinder of conjugated internal diameter of the outer diameter of the syringe 1, adapted so that said syringe prohibits a radial retraction of said flexible blades. In addition, each of the flexible blades 29, 30 comprises an oblique end end portion 29a, 30a intended to facilitate its introduction into the protective case 7. Each of these flexible blades 29, 30 comprises, finally, an external transverse rib 31, 32 having radial end faces intended to be irreversibly housed in the slots 17 of the protective case 7, in a position of protection after use in which the injection needle 2 is protected inside the protective case.

Finally, it should be noted that the two flexible blades 29, 30 are molded so as to converge in the direction of one another, and thus facilitate the crossing of the transverse ribs 18 of the protective case 7 by the external ribs 31, 32 of said flexible blades.

The injection device according to the invention comprises, lastly, a helical spring 33 adapted to be disposed in the rear section 9 of the protective case 7, and to be held compressed between the shoulder 10 of said case. protection and the annular front face 23 of the ring 21, in the position of said ring where its external ribs 26 are 101ogées in the slots 19 of the protective case 7. The assembly of the injection device described above consists, in the first place, to arrange the spring 33 in the rear section 9 of the protective case 7, then to introduce the intermediate piece 20 into said protective case by presenting it opposite said posterior section, until 15obtaining the relative locking in translation of the ring 21 and the protective case 7 in the injection position in which: - the rear ribs 26 of the ring 21 are housed in the slots 19 of the protective case, - The spring 33 is held compressed between the ring 21 and the shoulder 20, - the injection needle 2 extends in the extension of the protective case 7. It should be noted that this assembly can be done through the flexibility of the flexible blades 29, 30 which allows the crossing of the transverse ribs 18 of the protective case 7 by the outer ribs 31, 32 of said flexible blades. To facilitate this crossing, the two flexible blades 29, 30 may further be molded so as to converge towards one another.

The second step of the assembly consists, then, in introducing the syringe 1 in the protective case 7 until the collar 1b is locked inside the ring 21, in a position where the blades are flexible. 29, 30 are "stiffened" by the syringe 1 introduced between said flexible blades. The injection can then be carried out conventionally by antagonistic action on the pusher 6 and the digital support members 11. At the end of the injection, the profiled edge 6a of the pusher 6 cooperates with the profile edge 25a of the legs 25 of the ring 21, leading to deform radially inward said tongues and to cause the release of the posterior ribs 26. Once the injection is completed and the force on the pusher 6 removed, the ring 21 is pushed back to the rearward by the spring 33, driving the syringe 1, until the anterior ribs 31, 32 of the blades 10souples 29, 30 are housed irreversibly in the slots 17 of the protective case 7, in a position after use shown in FIG. 5 in which the injection needle 2 is protected inside the protective case

Claims (1)

CLAIMS1 / Secure disposable injection device characterized in that it comprises in combination: - a syringe (1) carrying an injection needle (2) and 5dotée a posterior collar (1 b), the said syringe housing a piston (4) slidable between a retracted position and an advanced end position, associated with a piston rod (5) having a push button (6), - a protective case (7) with of digital support members (11), adapted so that the syringe (1) is able to slide inside said protective case between an injection position in which the injection needle (2) s extends at least partially in the extension of the protective case (7), and a position of protection after use in which the injection needle (2) is fully housed in the protective case (7), - and an intermediate piece (20) for connection between the syringe (1) and the protective case (7), comprising a bead gue (21) adapted to be positioned in the protective case (7), and at least one radially deformable longitudinal flexible blade (29, 30), said ring comprising means (27, 29) for locking the collar ( 1 b) of the syringe (1), in a position where each flexible blade (29, 30) extends along this syringe (1), in a radially expanded state by said syringe: - the ring (21) ) and the protective case (7) comprising end stop members (10, 23) of the ends of resilient means (33) arranged between said stop members and adapted so that each flexible blade (29, 30) is extended inside and in the extension of said elastic means, - the ring (21) and the protective case (7) comprising conjugate means (19, 25, 26) of relative locking in translation, called posterior, adapted to: - ensure relative locking in translation of 301a said ring and said protective case in an injection position in which the elastic means (33) are held in a compressed state between the abutment members (10, 23) of said ring and said protective case, - switch to an unlocked state able to allow, at the end of the race, piston (4) inside the syringe (1), sliding said syringe and ring (21) to the protective position after use, and at least one flexible blade (29, 30) and protective case (7) comprising means (15-18, 31, 32) for relative translation locking said earlier, adapted to ensure relative locking in translation of said protective case and each of said flexible blades in its state radially expanded, in the protective position after use. 2 / injection device according to claim 1 characterized in that each flexible blade (29, 30) of the intermediate connecting piece (20) has a natural shape in which it has a longitudinal axis converging towards the axis of revolution of the ring (21). 3 / injection device according to one of claims 1 or 2 characterized in that the ring (21) of the intermediate connecting piece (20) comprises a rear portion (25) radially deformable carrying the rear means (26). relative locking device in translation, arranged to be deformed by the pusher (6) of the piston rod (5) at the end of stroke of the piston (4), so as to switch said rear locking means to their unlocked state. 4 / injection device according to one of claims 1 to 3 characterized in that the protective case (7) is shaped so as to define, for each flexible blade (29, 30), a groove (14) of section 25adapted to accommodate said flexible blade, in which are provided the front means (15-18) relative locking in translation of said protective case. 5 / injection device according to one of claims 1 to 4 characterized in that the protective case (7) comprises two longitudinal sections (8, 9) of different diameters separated by a shoulder (10): - an anterior section ( 8) adapted to guide the syringe (1) and each flexible blade (29, 30) during their sliding to the protective position after use, - a rear section (9) of conjugated diameter of that of the ring (21), adapted to form a housing for the resilient means (33) extending between the shoulder (10) and said ring. 6 / Injection device according to claims 4 and 5 taken together, characterized in that the protective case (7) comprises an anterior section (8) of internal section conjugate of the outer section of the syringe (1), having for each flexible blade (29, 30), a longitudinal outer boss (12, 13) defining the guide groove (14) of said flexible blade. 10 / Injection device according to one of claims 1 to 6 characterized in that the prior locking members relative to translation comprise: - a transverse rib (31, 32) provided with radial locking end faces, formed on each flexible blade (29, 30), and for each flexible blade (29, 30), a lumen (17) of conjugated shape of the transverse rib (31, 32) of said flexible blade, formed in the peripheral wall of the protective case (7), and delimited by a front tongue (15) elastically deformable radially, access to said light. 8 / injection device according to one of the preceding claims characterized in that the intermediate connecting piece (20) comprises two flexible blades (29, 30) diametrically opposed.