WO1999010033A1

WO1999010033A1 - Ring for protecting a used needle

Info

Publication number: WO1999010033A1
Application number: PCT/CH1998/000340
Authority: WO
Inventors: Raphaël PEGAITAZ
Original assignee: Pegaitaz Raphael
Priority date: 1997-08-21
Filing date: 1998-08-12
Publication date: 1999-03-04
Also published as: AU8527698A; FR2767480A1

Abstract

The invention concerns a receptacle designed to receive a hypodermic needle point (2), comprising a body (4, 5) with a generally cylindrical shape, coaxial to said needle and movable along same, a mobile member (6) with a generally cylindrical shape mounted sliding inside the body between an upstream position and a downstream position, a spring (7) tending to move the mobile member downstream, closing means for preventing it from passing through towards the body downstream opening when the body has been brought at the level of the needle point (2'), and locking means for blocking the body on the needle when the closure has been completed. The closing means comprise three balls (8) distributed in a space defined by the body downstream ends (4, 5) and the mobile member (6) and subjected by the latter to a centripetal force such that: as long as the body is not at the needle point (2'), the mobile member remains in its upstream position and the balls (8) are in contact with the needle (2); and when the body reaches the needle point (2'), the mobile member takes up its downstream position and the balls (8) obstruct the passage of the needle towards the downstream opening.

Description

RING FOR PROTECTING THE END OF A USED NEEDLE.

The present invention relates to a receptacle intended to receive, after use, the end of a needle for medical application, such as a hypodermic needle.

It is known, to avoid contamination of nursing staff and maintenance personnel with a used needle, to immediately enclose its pointed end in a receptacle or cap which is made to slide from its other end.

Generally, the protective receptacle comprises a cylindrical body, the end of which is automatically closed off, under the action of a spring, when at the end of the sliding of the receptacle towards the tip of the needle, the latter s is imprisoned there. The shutter mechanism is, moreover, supplemented by a locking system which at the same time blocks the receptacle on the needle so as to guarantee the confinement of its tip.

A device of this type is, for example, described in document WO 90/08564.

These receptacles must be inexpensive, small in size and light. Indeed, as soon as such a device is for single use since it remains attached to the needle after its use and is therefore discarded with it, it is essential that its cost price be as low as possible. In addition, its radial and axial dimensions play a particularly important role during an intravenous introduction because the needle is introduced at a very small angle relative to the surface of the arm. If the dimensions of the receptacle are too large, the penetration angle must then be increased, which makes it difficult to introduce a needle into the vein. Finally, the weight of the device must not, of course, affect the handling of the syringe. The object of the present invention is to provide a receptacle for a needle for medical application, of weight, diameter and length as small as possible and of particularly economical manufacture.

The receptacle according to the invention is of the type comprising:

a body of generally cylindrical shape, coaxial with the needle and movable along the latter, the downstream end of which is situated on the side of the point of the needle and the upstream end of which is situated on the opposite side, have openings allowing the passage of the needle,

- a movable tubular member mounted to slide inside the body between an upstream position and a downstream position,

- a spring tending to move the movable member downstream; shutter means making it possible, when the body is brought to the level of the point of the needle, to prohibit the passage of the latter towards the downstream opening of the body, and

- Locking means allowing, when the obturation is performed, to block the body on the needle. This receptacle is characterized in that the sealing means comprise three balls distributed in a space delimited by the downstream ends of the body and of the movable member and subjected, on the part of the latter, to a centripetal force, so that :

- as long as the body is not at the point of the needle, the movable member remains in its upstream position and the balls are in contact with the needle, and

- When the body arrives at the point of the needle, the movable member takes its downstream position and the balls obstruct the passage of the needle towards the downstream opening of the body. Advantageously, the downstream end of the movable member comprises a cylindrical element having three housings intended for the three balls and keeping them regularly distributed.

The locking means comprise at least one blade provided with a cutting edge, slidingly mounted in a housing of the body perpendicular to the needle and positioned relative to the movable member so that:

- when the movable member is in its upstream position, the blade is free in its housing, and - when the movable member is in its downstream position, the blade is subjected, on the part of the latter, to a force which apply its cutting edge against the needle to lock it.

According to an advantageous embodiment, the upstream end of the movable member is in a truncated cone and comes into contact with the blade to subject it to the force which applies its cutting edge against the needle.

Preferably, the locking means comprise two identical blades mounted head to tail in the same housing.

The invention will be better understood on reading the description which follows, made with reference to the accompanying drawings, in which:

- Figure 1 shows a needle provided with the receptacle according to the invention in the position it occupies before use, in 1a, and after use, in 1b;

- Figure 2 shows an enlarged view of this receptacle before use, in 2a, and after use, in 2b; and

Figures 3, 4 and 5 are sectional views taken respectively along lines III-III, IV-IV and VV of the receptacle shown in Figure 2, before use, in "a", and after use, in "b".

The receptacle 1 shown in the figures is mounted on a needle 2 for medical application, such as a hypodermic needle, one end of which is provided with a point 2 'intended to be introduced, for example, into the vein of a patient , and the other end of which carries a guard 3 intended to be threaded onto the tip of a syringe, in particular. As can be seen in Figure 1, the receptacle 1 is placed against the guard 3 before and during use of the needle 2. When withdrawing the needle, the receptacle is manually slid along the needle 2 to its point 2 "to trap it and thus make it harmless. The manner in which the imprisonment is carried out will be specified in detail below.

The receptacle 1 mainly comprises a body formed by a tube 4 and a plug 5, a movable member 6, a spring 7, three balls 8 and two blades 9.

The tube 4 is cylindrical in shape and coaxial with the needle 2. Its end 4 'opposite the guard 3, hereinafter the downstream end, is folded down to close it partially. It is advantageously made by means of a thin metal sheet formed by stamping. Its outside diameter is slightly smaller than that of the guard 3.

As can be seen in FIGS. 2a and 2b, the tube 4 has a window 4 "allowing the movable member 6 to be seen and the function of which will be specified below.

The plug 5 partially seals the tube 4 at its end closest to the guard 3, hereinafter the upstream end, and has a central opening 10 allowing the needle to pass 2. It comprises a first cylindrical portion 11 embedded in the tube 4 and a second cylindrical portion 12, of smaller diameter, which is pierced with an opening of rectangular section 13. The functions of the second portion 12 and of the opening 13 will be specified below. The stopper 5 is advantageously made of an injected plastic material which lends itself well to medical applications.

The movable member 6 comprises a tubular part 14 concentric with the tube 4 and of slightly smaller diameter. It is advantageously made of stamped metal sheet and its upstream end has a truncated cone 15 which encircles the second portion 12 of the plug 5.

The part 14 comprises, moreover, in its portion adjacent to the window 4 ", two zones 14 'and 14" (shown with hatching) which bear different colors, for example green and red respectively.

A cylindrical element 16, pierced in its center with a channel 17 allowing the needle 2 to pass, is embedded in the downstream end of the tubular part 14. It has, on the side facing the downstream end 4 'of the tube 4, three housings 18 (see more particularly FIG. 5) which are regularly spaced and open into the central channel 17. These housings are shaped and dimensioned so as to receive respectively the three balls 8 whose diameter is substantially equal to that of the '' needle and which are made of hardened steel, like those used in ball bearings. The element 16 can be made of injected plastic or metal.

As shown in Figures 2a and 2b, the balls 8 are trapped in a space formed by the element 16 and the end 4 'of the tube where they can occupy two positions. When the needle 2 is present in the channel 17 (FIG. 2a), the balls are only partially in their respective housings 18 which only serve to position them angularly. On the other hand, when the needle releases the channel 17 (FIG. 2b), they are completely inside the element 16. The spring 7 is of the flange type. It is supported, on the one hand, against the downstream end of the plug 5 and, on the other hand, against the upstream part of the element 16. It is reinforced so as to exert a force tending to move the plug axially away 5 and element 16 from each other.

As can be seen more particularly in Figures 3 and 4, the two blades 9 are identical. They have the shape of a truncated washer whose diameter is substantially equal to that of the second portion 12 of the plug 5 and whose truncated part has a width slightly less than that of the opening 13. They are arranged head to tail. 'against each other in this opening, inside which they can slide freely.

Each blade 9 has a slightly flared cut 19 made in the center of one of its rounded portions and crossed by the needle 2. This cut has a depth which corresponds substantially to two-thirds of the diameter of the blade 9 and has a straight bottom formed at a bevel, so as to define a cutting edge 20 whose edge is located on the downstream side. As already indicated, the two blades 9 are placed head to tail, that is to say that their respective cutting edges 20 face each other on either side of the needle 2.

The blades 9 can advantageously be manufactured by stamping a steel sheet harder than the body of the needle.

The operation of the receptacle according to the invention will now be described.

Before and during the use of the needle 2, the various constituent parts of the receptacle 1 occupy the positions presented on the parts identified by an "a" in FIGS. 1 to 5. The upstream end of the plug 5 is then adjacent to the guard 3 of the needle. The three balls 8 bear against the needle and against the end 4 ′ of the tube 4, under the effect of the force generated by the spring 7 and applied to the balls 8 by the peripheral part of the element 16. The presence of needle 2 in the central channel 17 does not does not allow full entry into their respective housings 18. The pressure that the balls 8, subjected to a centripetal force, thus exert on the needle 2 is sufficient to take the place of friction and thus prevent the receptacle 1 from inadvertently moving the along the needle.

The blades 9 can move freely inside the opening 13 of the plug 5, within the limits authorized by the needle 2 engaged in their openings 19.

In this position, the green zone 14 'of the part 14 is visible through the window 4 "of the tube 4. This shows that the needle is new and can be used.

When, at the end of an injection, a sampling or the implantation of a catheter, the needle 2 is withdrawn from the patient, a pressure exerted on the receptacle 1 by means of a tampon makes it possible to do so slide on the needle until the latter is extracted and its point 2 'is then immediately trapped. The receptacle 1 then occupies the position shown in parts "b" of FIGS. 1 to 5.

More precisely, from the moment the point 2 ′ of the needle releases the central channel 17 from the element 16, the balls 8, always subjected to the action of the spring 7 which relaxes, completely penetrate into their respective housings 18 and are trapped therein because the element 16 has moved downstream at the same time without however coming to bear against the end 4 ′ of the tube. In this position, the balls 8 escape the centripetal force. The space which they define between them then has an insufficient section to allow the passage of the needle 2. The channel 17 is thus sufficiently closed to prevent the tip 2 'of the needle from coming out of the receptacle 1.

Simultaneously, the tube 14, integral with the element 16, is moved axially downstream under the effect of the spring 7. Its end in the form of a truncated cone 15 then comes into contact with the rounded peripheral portions of the blades 9 and applies to them a radial force which projects their cutting edges 20 against the needle 2. The receptacle 1 is thus blocked on the needle under the action of the spring 7 and does not can no longer be removed.

In addition, the axial displacement of the tubular part 14 brings its red zone 14 "under the window 4". This shows that the syringe is now definitely out of use.

The structure as described above makes it possible to produce a remarkably economical receptacle, since it comprises a limited number of parts, all of which can be manufactured by techniques that can be easily automated, using inexpensive materials.

The diameter of the receptacle being smaller than that of the guard 3, it can be adapted on catheter needles.

Finally, the receptacle is very light, its mass being around 0.5 g, which does not affect the handling of the syringe.

The solution described can, of course, be the subject of several variants, relating in particular to the techniques used to manufacture the various parts and assemble them, without however departing from the scope of the invention.

It is thus possible to associate the downstream end 4 ′ of the tube 4 with the housings intended to receive the balls 8, the cylindrical element 16 then having the function of confining the balls 8 in their housings when the receptacle is in the closed position.

In another variant, not shown in the drawing, the blades 9 can be slightly inclined, so that their point of support on the conical part 15 of the movable member 16 is located on the same circumference.

Claims

1. Receptacle intended to receive the tip (2 ′) of a needle for medical application (2), comprising: - a body (4, 5) of generally cylindrical shape, coaxial with the needle and movable along it ci, whose downstream end (4 '), located on the side of said point, and the upstream end, located on the opposite side, are provided with openings allowing the passage of the needle, - a movable tubular member (6 ) slidably mounted inside the body between an upstream position and a downstream position,

- a spring (7) tending to move the movable member (6) downstream,

shutter means making it possible, when the body (4, 5) has been brought to the level of the tip (2 ′), to prohibit the passage of the latter towards the downstream opening of the body, and

- locking means making it possible, when the obturation is performed, to block the body on the needle (2), characterized in that said obturation means comprise three balls (8) distributed in a space delimited by the downstream ends of the body (4, 5) and of the movable member (6) and subjected, on the part of the latter, to a centripetal force, so that:

- as long as the body is not at the point (2 ') of the needle, the movable member remains in its upstream position and the balls (8) are in contact with the needle (2), and - When the body arrives at the point (2 ') of the needle, the movable member takes its downstream position and the balls (8) obstruct the passage of the needle towards the downstream opening of the body.

2. Receptacle according to claim 1, characterized in that the downstream end of the movable member (6) comprises a cylindrical element (16) having three housings (18) intended for the balls (8) and maintaining them regularly distributed in said space.

3. Receptacle according to one of claims 1 and 2, characterized in that said locking means comprise at least one blade (9) provided with a cutting edge (20), slidably mounted in a housing (13) of the body perpendicular to the needle (2) and positioned relative to the movable member (6) so that:

- when the movable member is in its upstream position, the blade (9) is free in its housing (13), and

- When the movable member is in its downstream position, the blade (9) is subjected, on the part of the latter, to a force which applies its cutting edge (20) against the needle (2) to lock it.

4. Receptacle according to claim 3, characterized in that the upstream end of the movable member (6) is in a truncated cone (15) and comes into contact with the blade (9) to subject it to the force which applies its cutting edge (20) against the needle (2).

5. Receptacle according to one of claims 3 and 4, characterized in that said locking means comprise two identical blades (9) mounted head to tail in the same housing (13).

6. Receptacle according to one of claims 1 to 5, characterized in that said body (4,5) comprises a window (4 ") through which the movable member (16) is visible, and in that said member has a first area (14 ') and a second area (14 ") of different aspects and arranged so that the first area is visible as long as said member is in the upstream position and the second appears when said member is in position downstream.