Rigid needle protector, method and machine for assembling such a rigid needle protector

Abstract

An assembly machine for assembling a rigid needle guard (10) having an inner part (11) made of elastomeric material, and a rigid outer body (12) that is fastened to the inner part (11) made of elastomeric material via a folded-in portion (121) of the bottom axial end of the rigid outer body (12). The folded-in portion (121) extends radially inwards from the outer peripheral surface (125) of the rigid outer body (12), the outer surface of the folded-in portion (121) forming, at its axially-bottom and radially-outer edge, a sharp and acute angle relative to the outer peripheral surface (125) of the rigid outer body (12).

Claims

1. An assembly machine for assembling a rigid needle guard, the rigid needle guard having an inner part made of elastomeric material, and a rigid outer body that is fastened to the inner part made of elastomeric material via a folded-in portion of a bottom axial end of the rigid outer body, the folded-in portion extending radially inwards from an outer peripheral surface of the rigid outer body, wherein the outer peripheral surface of the folded-in portion forms, at an axially-bottom and radially-outer edge, a sharp and acute angle relative to the outer peripheral surface of said rigid outer body; wherein the assembly machine is configured to assemble the rigid needle guard in the following steps: inserting the inner part made of elastomeric material into the rigid outer body; folding the bottom axial end of the rigid outer body radially inwards by a folder head, so as to form a folded-in portion that fastens the inner part made of elastomeric material in the rigid outer body; and deforming the folded-in portion with a shaper head so as to shape, on the axially-bottom and radially-outer edge of the folded-in portion, a sharp and acute angle relative to the outer peripheral surface of the rigid outer body; wherein, the machine comprises: an inserter unit for inserting the inner part made of elastomeric material into the rigid outer body; the folder head for forming a folded-in portion that extends radially inwards, so as to fasten the inner part made of elastomeric material in the rigid outer body; and the shaper head for deforming a rounded outer surface of the folded-in portion so as to shape, on the axially-bottom and radially-outer edge of the folded-in portion, the sharp and acute angle relative to the outer peripheral surface of said rigid outer body.

2. The machine according to claim 1, wherein at least one of the folder head or said shaper head operate by heat or by ultrasound.

3. The machine according to claim 1, wherein the sharp and acute angle is less than 90°.

4. The machine according to claim 1, wherein the sharp and acute angle is triangular in shape.

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 example, and with reference to the accompanying drawing, in which:

(2) FIG. 1 is a diagrammatic section view of a prior-art rigid needle guard that is arranged in a remover member;

(3) FIG. 2 is a diagrammatic section view of the FIG. 1 rigid needle guard, during assembly, with the inner part made of elastomeric material inserted into the rigid outer body;

(4) FIG. 3 is a diagrammatic section view of the FIG. 2 rigid needle guard, during assembly, with a folder head deforming the bottom axial end of the rigid outer body, so as to fasten said inner part made of elastomeric material;

(5) FIG. 4 is a view of a detail showing the shape of the folder head and the shape of the folded-in portion made by the folder head;

(6) FIG. 5 is a view similar to the view in FIG. 3, showing an advantageous embodiment of the present invention, before actuating a shaper head;

(7) FIG. 6 is a view similar to the view in FIG. 5, during actuation of the shaper head;

(8) FIG. 7 is a view of a detail of FIG. 5, after actuating the shaper head;

(9) FIG. 8 is a diagrammatic section view of a rigid needle guard in an advantageous embodiment of the present invention, arranged in a remover member; and

(10) FIGS. 9 and 10 are diagrammatic views, respectively in perspective and in section, of the FIG. 8 unit, when assembled on a syringe provided with a needle.

(11) In the description below, the terms “top” and “bottom” refer to the upright position of the rigid needle guard shown in the figures. The terms “axial” and “radial” refer to the longitudinal central axis A shown in FIG. 8.

(12) The present invention applies to a rigid needle guard 10 comprising an inner part 11 made of elastomeric material, such as rubber or a TPE material, and a rigid outer body 12. Said rigid outer body 12 includes a bottom axial end and a top axial end surface 122. Said rigid outer body 12 is fastened to said inner part 11 made of elastomeric material via a folded-in portion 121 that is formed on the bottom axial end of said rigid outer body 12. Said folded-in portion 121 extends radially inwards from an outer peripheral surface 125 of said rigid outer body 12.

(13) Said folded-in portion 121 is made, in known manner, by a folder head 30 that includes a folder cavity 31 of rounded shape that is adapted to deform said bottom axial end of said rigid outer body 12 so as to form a folded-in portion of rounded shape.

(14) In the invention, the outer surface of said folded-in portion 121 forms, at its axially-bottom and radially-outer edge, a sharp and acute angle, preferably less than 90°, relative to the outer peripheral surface 125 of said rigid outer body 12.

(15) The sharp and acute angle is formed by means of a shaper head 40 that modifies the rounded shape of said folded-in portion 121 formed by said folder head 30.

(16) Folding by means of said folder head 30, which gives a rounded profile to said folded-in portion 121 so as to guarantee that said inner part 11 made of elastomeric material is fastened in said rigid outer body 12, is required, in particular so as to avoid any risk of crushing said outer body 12.

(17) Thus, it is not desirable to modify the folder cavity 31 of the folder head 30 so as to give it a shape that defines a sharp and acute angle, since that would risk, during folding of the bottom axial end of said rigid outer body 12, deforming or crushing said rigid outer body 12, which could spoil said needle guard 10. Specifically, it is desirable, during the folding step, that the folded-in portion 121 extends radially inwards only, and that it does not form any radially-outward deformation on said outer peripheral surface 125 of said rigid outer body 12. In addition, it is desirable, during the folding step, that the folded-in portion 121 does not compress or deform said inner part 11 made of elastomeric material.

(18) The invention thus envisages using the folder head 30 of the conventional assembly method and machine for forming a folded-in portion of rounded shape, and of adding thereto a shaper head 40 that acts after said folder head 30 so as to form said sharp and acute angle on said rounded folded-in portion.

(19) Said shaper head 40 thus includes a shaper cavity 41 that defines a sharp and acute angle, the shaper cavity 41 coming to co-operate with said folded-in portion 121 so as to form, at its outer surface, a sharp and acute angle with the outer peripheral surface 125 of said rigid outer body 12.

(20) The shape of said shaper cavity 41 shown in FIG. 7 is advantageous, but any other appropriate shape that makes it possible to generate a sharp and acute angle in the folded-in portion 121 at its axially-bottom and radially-outer edge could be envisaged.

(21) Advantageously, said folder head 30 and said shaper head 40 operate hot, thereby making it easy to deform said folded-in portion 121 formed on the bottom axial end of said rigid outer body 12. In a variant, one or the other, or both of the folder and shaper heads 30, 40 could alternatively operate by ultrasound.

(22) With the folded-in portion 121 shaped in accordance with the present invention with a sharp and acute angle, there is no longer any risk of a remover member 20, used for removing the rigid needle guard 10, e.g. in an autoinjector, sliding over said folded-in portion, as occurs with the rounded folded-in portion in FIG. 1.

(23) The remover member 20 includes a manual grip zone 25 on which the user places the fingers, so as to exert axial traction on the remover member. The remover member also includes a co-operation zone 21 for co-operating with said rigid needle guard 10, said co-operation zone 21 comprising at least one shoulder that extends radially inwards and that co-operates with said folded-in portion 121 of said rigid outer body 12 of said rigid needle guard 10. Thus, axial movement of said remover member 20 causes axial movement of said rigid needle guard 10. As can be seen in FIG. 8, as a result of the presence of the sharp and acute angle on the folded-in portion 121 of the invention, said at least one shoulder 21 of the remover member can no longer be disengaged from said folded-in portion 121, and removal of the rigid needle guard 10 is thus guaranteed with axial movement of the remover member 20.

(24) In FIGS. 9 and 10, a syringe comprising a reservoir 1 and a needle 2 is provided with a rigid needle guard 10 of the invention. Advantageously, said syringe is provided with a unit formed of such a rigid needle guard 10 and a remover member 20. Naturally, the syringe also includes a piston that is adapted to slide in the reservoir 1, a piston rod generally being provided so as to move said piston during injection. However, these elements and not shown in FIG. 10 since they do not form part of the present invention.

(25) The present invention is described above with reference to a particular embodiment, but naturally it is not limited by said embodiment, but on the contrary, any useful modifications can be applied thereto by the person skilled in the art, without going beyond the ambit of the present invention, as defined by the accompanying claims.