Moulding assembly and method for producing a syringe body

Abstract

A molding assembly for manufacturing a syringe barrel, each syringe barrel provided with a cannula and having a cylindrical portion and a hub portion to which the cannula is fastened. A mold unit is provided having a first mold portion, a second mold portion axially movable relative to the first mold portion between an open position and a closed position, and a core situated in the mold cavity; and a clip unit for the cannula movable between an open position in which a cannula can be loaded in a proximal axial end of the clip, and a closed position. The clip unit is axially movable so as to arrange a cannula in the mold cavity, the movement of the clip being independent of the axial movement of the first and second mold portions between the open and closed positions of the mold unit.

Claims

1. A method of manufacturing a syringe barrel provided with a cannula, said syringe barrel comprising a cylindrical portion and a hub portion on which said cannula is fastened, the manufacturing method comprises the following steps: providing a clip unit including a clip that is movable between a closed position and an open position; opening said clip by means of an actuator element of said clip unit, said actuator element being controlled by a control member; loading a cannula (20) into said open clip by means of a cannula-loading unit; closing said clip on said cannula; moving said clip unit containing said cannula sideways to face a mold unit comprising a first mold portion and a second mold portion that is axially movable relative to said first mold portion between an open position and a closed position in which said first and second mold portions co-operate with each other to define a mold cavity between them, a core being situated in said mold cavity so as to define the shape of said syringe barrel; moving said clip unit containing said cannula axially relative to said mold unit, so as to insert said cannula into said mold unit; injecting synthetic material into said mold unit so as to mold said syringe barrel around said cannula; opening said clip by means of said actuator element of said clip unit, said actuator element being controlled by a control member, such as a jack; and opening said mold unit so as to eject said syringe barrel molded around said cannula.

2. A method according to claim 1, wherein said step of moving said clip unit containing said cannula axially relative to said mold unit so as to insert said cannula into said mold unit is performed as follows: opening said mold unit by moving said second mold portion axially relative to said first mold portion; inserting said clip unit into said second mold portion; and closing said mold unit by moving said second mold portion, together with said clip unit, axially relative to said first mold portion.

3. A method according to claim 1, wherein said step of moving said clip unit containing said cannula axially relative to said mold unit so as to insert said cannula into said mold unit is performed as follows: closing said mold unit by moving said second mold portion axially relative to said first mold portion; and moving said clip unit containing said cannula axially relative to said closed mold unit so as to insert said cannula into said mold unit.

4. A method according to claim 1, wherein said step of moving said clip unit containing said cannula sideways is performed by means of a pendular arm.

5. A method according to claim 1, wherein in the closed position of said clip, said cannula may be moved axially relative to said clip.

6. A method according to claim 5, wherein, when said cannula is inserted into said mold unit, the axial end of said cannula that is remote from said perforating tip co-operates with a positioner member of said mold unit, so as to ensure that said cannula is positioned accurately in said mold unit while molding the syringe barrel.

7. A method according to claim 1, wherein said clip includes a recess that receives the perforating tip of the cannula in all positions, such that no stress is exerted on said perforating tip while loading said cannula into said clip by said cannula-loading unit, while moving said clip, and while molding said syringe barrel around said cannula by said mold unit.

8. A method according to claim 1, wherein said step of opening said clip so as to load said cannula is performed by a first control member, and said step of opening said clip after molding said syringe barrel is performed by a second control member, said control members being actuated independently of each other, and independently of the movements of said mold unit.

9. A method according to claim 1, wherein said step of closing said clip is performed automatically, said clip being urged resiliently towards its closed position.

10. The method according to claim 1, wherein the control member is a jack.

11. The method according to claim 4, wherein the pendular arm is pivotally mounted.

Description

(1) These characteristics and advantages and others of the present invention appear more clearly from the following detailed description, given by way of non-limiting examples, and with reference to the accompanying drawings, and in which:

(2) FIGS. 1A and 1B are perspective and cross-section views respectively of a molding assembly in an advantageous embodiment of the invention, in the closed position of said molding assembly;

(3) FIG. 2 is a cross-section view of a detail of a clip in its closed position, without a cannula;

(4) FIG. 3 is a cross-section view of a clip in its open position, without a cannula;

(5) FIG. 4 is a view similar to the view in FIG. 3, with the clip in its closed position;

(6) FIG. 5 is a cross-section view of the clip in its closed position containing a cannula, with the clip arranged outside the mold;

(7) FIG. 6 is a cross-section view of the mold in its open position, with the clip in its closed position, with a cannula;

(8) FIG. 7 is a view similar to the view in FIG. 6, with the mold in its closed position;

(9) FIG. 8 is a view similar to the view in FIG. 7, while the syringe barrel is being injected;

(10) FIG. 9 is a view similar to the view in FIG. 8, after the syringe barrel has been injected onto the cannula, with the clip in its open position; and

(11) FIG. 10 is a view similar to the view in FIG. 9, with the mold in its open position.

(12) In the description below, the terms “axial”, “radial”, and “transverse” are relative to the longitudinal axis of the cannula in the mold unit, i.e. the vertical axis in FIGS. 1B and 2 to 10. The terms “proximal” and “distal” are relative to the cannula.

(13) The invention relates more particularly to the manufacture of a syringe barrel 10 provided with a cannula 20, said syringe barrel 10 comprising a cylindrical portion 11 forming a reservoir, and a hub portion 12 to which said cannula 20 is fastened.

(14) The invention is described below with reference to one complete cycle of the molding assembly, with reference to molding one syringe barrel 10 on one cannula 20. Naturally, the molding assembly may comprise a plurality of sub-assemblies that operate simultaneously.

(15) The molding assembly includes at least one mold unit 100, each mold unit 100 comprising a first mold portion 110 and a second mold portion 120 that is axially movable relative to said first mold portion 110 between an open position and a closed position. In this closed position, said first and second mold portions 110, 120 co-operate with each other to define a mold cavity 130 between them, and a core 140 that is situated inside said mold cavity 130 defines the shape of said syringe barrel 10.

(16) The molding assembly also includes at least one clip unit 200 for clipping the cannula 20, each clip unit 200 comprising a clip 210 that is movable between an open position in which a cannula 20 can be loaded into a proximal axial end of said clip 210, and a closed position in which said cannula 20 is held in said clip 210. Said clip unit 200 is axially movable relative to said mold unit 100 so as to place a cannula 20 in said mold cavity 130. The movement of said clip 210 between its open and closed positions is independent of the axial movement of said first and second mold portions 110, 120 between said open and closed positions of said mold unit 100.

(17) Each clip unit 200 includes an actuator element 220 that is axially movable between a closed position and an open position, said actuator element 220 being adapted to move said clip 210 between said closed and open positions.

(18) Advantageously, said actuator element 220 includes a frustoconical proximal axial end 221 that co-operates with a distal axial end 211 of said clip 210. The distal axial end 211 advantageously includes a hollow conical shape that is complementary to said frustoconical proximal axial end 221 of said actuator element 220, such that axial movement of said actuator element 220 causes radial movement of said clip 210 between said closed and open positions. In particular, when the actuator element 220 advances axially in said clip, its frustoconical proximal axial end 221 slides in the complementary hollow conical shape of said distal axial end 211 of said clip 210, and this causes said clip 210 to space apart radially and thus open.

(19) Advantageously, said clip 210 is urged resiliently towards its closed position. Thus, when the actuator element 220 moves axially back out of said clip, said clip closes automatically.

(20) A control member 230, such as a jack, that co-operates with said actuator element 220 of said clip unit 200 is designed to move said actuator element 220 between its closed and open positions. Actuation of the control member 230 is independent of the opening and/or the closing of the mold unit 100.

(21) The molding assembly further includes a cannula-loading unit 300 that is adapted to load a cannula 20 in a clip unit 200. The cannula-loading unit 300 may be of conventional type.

(22) In the embodiment shown in the figures, the molding assembly comprises two mold units 100 and two cannula-loading units 300 that are offset transversally, and four clip units 200 that are arranged in pairs on a pendular arm 250, in particular pivotally mounted. Thus, while the two cannula-loading units 300 load respective cannulas 20 into two clip units, each of the two mold units 100 mold a syringe barrel 10 around a cannula 20. Then, the pendular arm 250 pivots, and firstly brings the two clip units 200 loaded with cannulas 20 to face the two mold units 100, and secondly returns the other two clip units to face the two cannula-loading units 300. Advantageously, four control members 230 are provided to control the four clips 210 separately and independently. However, this advantageous embodiment is not limiting, and other configurations may be envisaged.

(23) Advantageously, the first mold portions 120 of the mold units are formed by a single plate. Advantageously, the second mold portions 120 of the two mold units are also formed by a single plate.

(24) It should be observed that there may be any number of mold units 100, of clip units 200, and of cannula-loading units 300, the above embodiment not being limiting.

(25) Advantageously, each clip 210 includes a recess 215 that receives the perforating tip 21 of the cannula 20 in all positions. Thus, no stress is exerted on said perforating tip 21, neither while loading said cannula 20 into said clip 210 by said cannula-loading unit 300, nor while moving said clip 210, nor while molding said syringe barrel 10 around said cannula 20 by said mold unit 100.

(26) Advantageously, each mold unit 100 includes a positioner member 150 that co-operates with the axial end of the cannula 20 that is remote from said perforating tip 21. This makes it possible to position said cannula 20 accurately in said mold unit 100 while molding the syringe barrel 10, without risk of damaging the perforating tip 21. In this respect, it is advantageous for the clip 210, in its closed position, to allow the cannula 20 to move axially a little relative to the clip, in particular by sliding.

(27) A cycle of manufacturing a syringe barrel is described below with reference to the figures, in order to illustrate the manufacturing method.

(28) The clip 210, closed in FIG. 2, is opened by means of an actuator element 220 of said clip unit 200, said actuator element 220 being controlled by a control member 230, such as a jack. The open position of the clip can be seen in FIG. 3.

(29) A cannula 20 is then loaded into said open clip 210 by means of a cannula-loading unit 300.

(30) Said clip 210 is then closed on said cannula 20, as shown in FIG. 4.

(31) Then, as shown in FIG. 5, said clip unit 200 moves axially away from said cannula-loading unit 300, said closed clip 210 containing a cannula 20 being arranged facing a cannula-loading unit 300.

(32) Said clip unit 200 containing said cannula 20 is then moved sideways so as to come to face a mold unit 100.

(33) Then, said clip unit 200 containing said cannula 20 is moved axially relative to said mold unit 100 so as to insert said cannula 20 into said mold unit 100. FIG. 7 shows the position with the closed mold unit 100 containing said cannula.

(34) Synthetic material is then injected into said mold unit 100 so as to mold said syringe barrel 10 around said cannula 20, as can be seen in FIG. 8.

(35) After molding, said clip 210 is opened by means of said actuator element 220 of said clip unit 200, said actuator element 220 being controlled by a control member 230, such as a jack, as can be seen in FIG. 9. The control member 230 may be different from the control member that was used to open the clip 210 in order to load the cannula. Thus, said step of opening the clip 210 so as to load the cannula 20 may be performed by a first control member 230, and said step of opening said clip 210 after molding said syringe barrel 10 may be performed by a second control member 230, said first and second control members 230 being actuated independently of each other, and independently of the movements of said mold unit 100.

(36) Finally, said mold unit 100 is opened so as to eject said syringe barrel 10 molded around said cannula 20, as shown in FIG. 10.

(37) The molding assembly is then ready for the next cycle.

(38) As explained above, the molding assembly shown in the figures makes it possible to manufacture two syringe bodies simultaneously.

(39) Advantageously, the step of moving said clip unit 200 containing said cannula 20 axially relative to said mold unit 100 so as to insert said cannula 20 into said mold unit 100 is performed as follows: said mold unit 100 is initially opened by moving said second mold portion 120 axially relative to said first mold portion 110; said clip unit 200 is inserted into said second mold portion 120, as can be seen in FIG. 6; and said mold unit 100 is closed by moving said second mold portion 120, together with said clip unit 200, axially relative to said first mold portion 110.

(40) In a variant, the step of moving said clip unit 200 containing said cannula 20 axially relative to said mold unit 100 so as to insert said cannula 20 into said mold unit 100 may also be performed as follows: said mold unit 100 is initially closed by moving said second mold portion 120 axially relative to said first mold portion 110; and said clip unit 200 containing said cannula 20 is moved axially relative to said closed mold unit 100 so as to insert said cannula 20 into said mold unit 100.

(41) Advantageously, said at least one cannula-loading unit 300 is fastened on said second mold portion 120. This makes it possible to correlate the movements of said cannula-loading unit 300 with the movements of said second mold portion 120, and thus improve accuracy in positioning the cannula 20 in the clip 210.

(42) The present invention thus makes it possible, in particular, to provide the following advantages: no contact takes place with the perforating tip 21 of the cannula 20 during the entire manufacturing method; this makes it possible to avoid any risk of damaging said perforating tip; the number of times the cannula 20 is transferred is small: the cannula is loaded into the clip and then it remains held in the clip until the end of the method of molding the syringe barrel 10 around the cannula 20; this also makes it possible to limit the risks of damaging the cannula, in particular by limiting contact with dirt or particles; as a result, exposure of the needle to external contaminants is greatly limited; and the cannula can be positioned very accurately in the mold unit while molding the syringe barrel.

(43) Although the present invention is described above with reference to an advantageous embodiment, naturally various modifications are possible for the person skilled in the art, without going beyond the ambit of the present invention, as defined by the accompanying claims.