EP0625058A1

EP0625058A1 - Protective cover for a blood-sample needle

Info

Publication number: EP0625058A1
Application number: EP92923818A
Authority: EP
Inventors: Christian Hirsch; Herbert Feit; Dieter Vogel
Original assignee: Sueddeutsche Feinmechanik GmbH
Current assignee: Sueddeutsche Feinmechanik GmbH
Priority date: 1991-12-05
Filing date: 1992-11-28
Publication date: 1994-11-23
Also published as: DE4140101C1; WO1993010840A1

Abstract

L'objet de la présente invention est une protection pour aiguilles de prise de sang. L'aiguille (12) est entourée d'une gaine extérieure (14), reliée par un point destiné à la rupture (16) à un moyeu (18) qui porte l'aiguille (12). A l'intérieur de cette gaine extérieure (14) se trouve, tout au moins dans la zone de la pointe (24) de l'aiguille, une gaine intérieure (28) qui entoure l'aiuille (12). La gaine intérieure (28) et la gaine extérieure (14) sont fabriquées par moulage par injection d'un produit à deux composants. La gaine intérieure (28) est protégée par liaison de forme et/ou de force avec la gaine extérieure (14) contre tout glissement axial sur l'aiguille (12).The object of the present invention is a protection for blood needles. The needle (12) is surrounded by an outer sheath (14), connected by a point intended for rupture (16) to a hub (18) which carries the needle (12). Inside this outer sheath (14) is, at least in the region of the tip (24) of the needle, an inner sheath (28) which surrounds the needle (12). The inner sheath (28) and the outer sheath (14) are produced by injection molding of a two-component product. The inner sheath (28) is protected by form and / or force connection with the outer sheath (14) against any axial sliding on the needle (12).

Description

description

Needle guard for a blood sampling needle

The invention relates to a needle guard, in particular intended for a blood sampling needle, with an outer sleeve arranged around a needle with a tip, within which an inner sleeve surrounding the tip of the needle extends at least in regions.

A needle guard of the type described above is known (D E 27 33 670 AI). This needle protection is intended to prevent the tip from digging into the wall of the sheath when the needle is twisted, as a result of which plastic splinters can come loose from the wall. Such plastic splinters may stick to the needle tip. If the plastic splinter is inserted unnoticed into the body or into a blood vessel of a pereon, the person can suffer health damage.

The inner sheath is also intended to ensure that liquid cannot escape from the needle.

In practice it has been shown that the inner sleeve remains on the needle when the outer sleeve is removed. Consequently, after the outer sheath has been removed, the inner sheath, which has no connection with the handle, is pulled off in the axial direction of the needle.

In the case of the known needle guard, the outer sheath is of hollow cylindrical design with an opening above the needle tip. The outer shell including the handle is z. B. manufactured by injection molding. After that the Inner sleeve produced in a special operation is inserted into the cylindrical opening and pushed over the tip of the needle. Then the opening of the outer shell is closed with a stopper which, for. B. is glued to the outer shell.

The manufacture of this needle guard is relatively complex. Since the outer and inner shells should be arranged concentrically, small manufacturing tolerances are required. In the event of production-related deviations from the tolerances, difficulties arise when assembling the parts.

Despite complex manufacturing and assembly processes, it is nevertheless not ensured that the inner and outer shells are aligned centrally with respect to one another such that, for. B. a puncture of the inner sleeve is excluded when inserting the needle. Rather, it must be ascertained again and again during assembly that the inner casing is pierced, so that the required tightness is no longer ensured. This in turn means that when used for a blood bag it cannot be stored, since the stabilizer solution present in the blood bag partially evaporates and the blood bag including the tube system would stick together (long-term evaporation process).

The invention is based on the problem of developing a needle guard of the type described at the outset in such a way that the inner sleeve can be fitted precisely around the tip of the needle with as little effort as possible and can be arranged in a fixed position within the outer sleeve. The needle guard should also be easy to manufacture and mountable on a needle.

The problem is essentially solved according to the invention in that the inner sleeve and the outer sleeve are parts manufactured in at least two-component injection molding and that the inner sleeve is secured in the axial direction of the needle by a positive and / or non-positive connection with the outer sleeve. Two- or multi-component injection molding is understood to mean that the needle guard, which is composed of the inner and outer shells, is produced in one workflow in a two- or multiple injection process.

The type of connection between the inner and outer cover according to the invention has the advantage that the relative position of the inner and outer cover is not changed by external stresses during storage or transport of the needle guard.

Even during assembly, that is to say arranging the protective cover on a needle, it is ensured that the needle is tightly surrounded by the inner cover. Piercing is not possible. Consequently, freedom from particles in the lumen is guaranteed.

Also, the inner shell can not due to external stresses such. B. temperature changes in connection with external forces, change their position within the outer shell. Rather, the desired centering of the inner shell remains within the outer shell, so that piercing of the inner shell is thus excluded. There is no danger that the needle tip will penetrate to the inner wall of the outer sleeve and thus pick up particles.

At the same time, due to the fixation of the inner sleeve in the outer sleeve, it is possible to provide a relatively small distance between the needle tip and the closed end of the inner sleeve facing it. The needle guard therefore only protrudes slightly beyond the tip of the needle, which saves material and space.

The needle guard is absolutely leak-proof and manufactured using the multi-component injection molding process. The outer shell, which is sprayed around the inner shell after it has hardened, is arranged on the inner shell with virtually no play and encloses it. Assembly work is unnecessary because of the production in one operation. The advantage of multi-component spraying is that external and the inner shell always have the desired wall thickness.

In a favorable embodiment, the inner shell is fused to the outer shell at least in some areas. This is guaranteed by the choice of materials for the outer and inner shell and the temperatures applied during injection molding.

Suitable materials as such are suitable plastics or plastics-like materials, in particular based on rubber. The materials can optionally also be filled, i. H. be glass fiber and / or carbon fiber reinforced. There is also the possibility of coloring the inner and / or outer shell or making it crystal clear. In particular, in the area of the needle cut, a magnifying effect can take place in order to be able to check the position and / or condition of the needle cut from the outside.

In another expedient embodiment, the inner sleeve at its end facing away from the needle tip has an end surface inclined towards the longitudinal axis of the needle, which facilitates insertion of the needle.

The inner surface of the inner shell can also be aligned with the free inner surface of the outer shell.

Furthermore, the inner shell can optionally protrude above the outer shell.

To achieve a positive connection between the inner and outer shells, the former can be provided with projections which are surrounded by the outer shell. Of course, only one protrusion, which may be circumferential, can also be provided.

In order to detach the outer cover from the handle, the outer cover is preferably rotated, as a result of which the separation occurs at the predetermined breaking point adjacent to the handle. This rotation does not affect the inner shell. After separation from the handle from the outer shell, the outer shell is pulled off axially. The inner shell will be taken along. This will expose the needle.

Further details, advantages and features of the invention result not only from the claims, the features to be extracted from them - by themselves and / or in combination - but also from the following description of preferred exemplary embodiments to be taken from a drawing.

Show it:

1 shows a cannula with needle guard in longitudinal section in an enlarged view,

2 shows a front part of a second embodiment of a needle guard with a needle in longitudinal section,

3 shows a front part of a third embodiment of a needle guard with a needle in longitudinal section,

4 - 13 further variants of needle shooters surrounding cannula needles in schematic diagrams,

14 shows a schematic diagram relating to the manufacture of a needle guard and

Fig. 15 is a principle division regarding the assembly of the needle guard on a needle.

In the following description of the exemplary embodiments, the same reference symbols are used in principle for the same elements. A needle guard (10) for a blood sampling or infusion needle (12) contains an outer cover or protective cap (14) made of plastic, which is integrally connected to a handle (18) by a thin, annular predetermined breaking point (16). Ribs (20) extend from the outer sheath (14) and facilitate the removal of the outer sheath (14) of the needle (12). The handle (18). has a recess (22) which is open towards the rear and into which the end (26) of the needle (12) remote from the needle tip (24) projects. For example, a blood collection tube, not shown, is pushed onto the end (26) and is connected to a blood bag of a conventional type.

In the embodiment of FIG. 1 there is an inner shell (28) inside the outer shell (14) which, like the outer shell (14), has a closed end (30). The inner sleeve (28) surrounds the needle tip (24) and the area of the needle (12) adjoining the needle tip (24). There is also a cavity (32) between the needle tip (24) and the front end (30) of the inner sleeve (28). The needle tip (24) therefore does not touch the end (30).

At least the inner shell (28) and the outer shell (14) are produced in a two-component injection molding process. The handle (18) is preferably also produced at the same time. Depending on the desired geometries or the tools to be used, a two- or multi-component injection molding process can be used.

In the two-component injection molding process, the inner shell (28) is first produced. The outer shell (14) is then optionally formed with the handle (18), the latter also being able to be produced in a third step. A double mold with different cavities is preferably used to produce the needle guard (10). The needle guard (10) is created in two work cycles.

If an intimate connection of the inner and outer shell (28) or (1) is to take place, suitable materials must be used accordingly. They are too To choose working temperatures accordingly.

However, an intimate connection is not absolutely necessary. Rather, there is also the possibility of a positive connection, such as. B. FIG. 2 is intended to clarify. Intimate connections and positive locking can also be present at the same time.

By manufacturing in the two-component injection molding process, in which the parts available after one work cycle are used as cores for the next work cycle, a precise centering between the inner shell (28) and outer shell (14) is achieved. Furthermore, the inner and outer shells have uniform wall thicknesses. The inner shell (28) is practically without tolerance, d. H. arranged without play in the outer shell (14). In the case of the needle guard (10) produced in the two-component injection molding process, an assembly work step is saved since the needle guard (10) can already be removed from the injection mold.

The positive connection between the inner shell (28) and the outer shell (14) ensures that the relative position between the inner and outer shell, for. B. during storage or transportation of the needle guard (10) or during its assembly, does not change. It can therefore not happen that the ground needle tip pierces the inner sleeve (28). Consequently, the desired tightness is always guaranteed on the one hand and on the other hand it is ensured that no plastic particles are peeled off the outer shell wall. The latter causes the lumen to be free of particles.

To remove the outer shell (14), it is rotated relative to the handle (18). The connection between the outer shell (14) and the handle (18) is broken at the predetermined breaking point (16). The rotary movement is facilitated by the ribs (20), which form a larger contact surface for the hand. As illustrated in FIG. 1, the inner sleeve (28) has an end face (34) which is distant from the needle tip (24) and is chamfered. This is to facilitate the insertion of the needle (12) into the needle guard (10).

It can also be seen from the illustration that the wall thickness of the outer casing or protective cap (14) is constant over its length. As a result, the inner shell (28) is deposited on the inner surface of the outer shell (14).

FIG. 2 shows a needle guard (35), in which the axial fixation and coaxial alignment of an inner sleeve (36) with an outer sleeve (38) is achieved in a different way than in FIG. 1. However, the two-component injection molding process is also used in relation to the inner shell (36) and the outer shell (38).

The inner sleeve (36) surrounds at least the needle tip (24), i.e. H. the inner shell (36) is also cap-shaped.

A positive connection is provided to ensure that the inner casing (36) is clearly fixed in position within the outer casing (38). On the one hand, this is achieved in that the inner shell (36) is received by the outer shell (38).

In the exemplary embodiment in FIG. 2, the inner surface (40) of the inner shell (36) therefore merges flush with the inner surface (46) of the outer shell (38).

To lock the inner casing (36) and the outer casing (38), the end region (44) of the inner casing (36) can be wedge-shaped.

In addition, protrusions (39) and (41) can extend from the outer surface (37) of the inner shell (36), which corresponding recesses (43) and (45) of the outer shell (38) extend. In this way, there is a positive connection between the inner casing (36) and the outer casing (38), without an intimate connection being necessary.

There is also the possibility that the projections (39), (41) and the associated recesses (43), (45) are formed all the way round or that the projections (39) and (41) extend to the outer surface (47). of the outer shell (38).

The embodiment of FIG. 3 provides a needle guard (48), which is composed of an outer shell (50) and an inner shell (52), which have been positively connected to one another and have been produced in a two-component injection molding process.

In order to ensure a clear positional fixation of the inner casing (52) in the outer casing (50), in particular a clearly concentric and alignment with the longitudinal axis (54) of the protective casing, projections (56) emanate from the inner casing (52) and are located within the outer casing (50) extend. These areas, which can be referred to simply as recess, have the reference symbol (58). It is not imperative - as is shown in the drawing - that the projections (56) protrude to the outer surface (60) of the outer shell (50).

The end region (62) of the inner shell (52) is chamfered and continues in a section (64) of the outer shell (50). It is hereby achieved that the wall thickness of the outer casing (50) outside the inner casing (52), that is to say in the area (66), is less than in the area of the inner casing (52).

4 to 13 show further variants of needle protection or protective cover arrangements, each of which is composed of an outer cover and an inner cover partially accommodated by it. The outer and inner shell are manufactured using the two-component injection molding process. The outer and inner shell can be connected either positively or non-positively. There is also a combination of these connection options. The outer and inner sheaths can also have different colors so that certain cannulas can be identified. Finally, there is the possibility that the handle is also produced together with the protective covering in a multi-component injection molding process, it being possible for the handle to be formed with the outer shell in one manufacturing step. Of course, two steps can also be carried out.

In the exemplary embodiments in FIGS. 4, 8, 9, 12 and 13, at least one form-fitting connection takes place in that projections extend from the respective inner shell and extend within the outer shell.

According to the exemplary embodiment in FIG. 4, an inner shell (68) has a projection (70) which is circumferentially arranged in its end region and is surrounded by the material of the outer shell (74).

Furthermore, the inner shell (68) is not completely absorbed by the outer shell (74). Rather, the outer sheath (68) projects with a section (76) over the outer sheath (74) without, however, leaving the features which characterize the invention in relation to the concentric arrangement with the longitudinal axis of the needle.

Of course, it is not absolutely necessary that the projection (70) is circumferential. Rather, the inner shell (68) can also be connected to the outer shell (74) in a type of toothing.

4, the inner wall of the inner sleeve (68) merges flush into the inner wall of the outer sleeve (74), ie that there is essentially no change in cross-section from the space accommodating the needle (not shown) 8 shows the open edge region (78) of an inner shell (80), which is preferably completely of an outer shell (82) is received, be expanded in a truncated cone shape. This ensures a safe insertion of a needle into the inner sleeve (80). In the area (78) in which the conical taper runs, the inner casing (80) also has a preferably circumferential projection (84) which runs inside the outer casing material.

A corresponding conical geometry can also be found in the exemplary embodiment in FIG. 9. The position of the corresponding inner shell (86) is clearly fixed by means of a laterally projecting projection (88) inside the outer shell (90). By means of the multi-component injection molding process, the projection (88) specifies the shape of the corresponding recess in the outer casing (90), since the inner casing (86) is at the same time the mandrel of the injection molding tool when the outer casing (90) is formed.

The embodiments of FIGS. 5 and 6 differ essentially in that an inner shell (92) is completely (FIG. 5) or partially (FIG. 6) surrounded by an outer shell (94) and (96). This surrounding is preferably carried out in a form-fitting manner in that at least a region-wise fusion takes place between the inner shell (92) and the outer shell (94) or (96). This area is indicated in FIG. 6 with the reference symbol (98).

In the embodiment of FIG. 5, instead of the intimate connection alone, a positive connection can take place in that the inner casing (92) is received by the outer casing (94) in such a way that a clear position fixation takes place. For this purpose, the outer shell (94) surrounds the inner shell over its entire outer surface, including the edge surface (100), which is covered by the outer shell (94).

In the exemplary embodiment in FIG. 10, an inner shell (102) extends beyond the outer shell (104), an intimate connection preferably taking place between the outer and inner shell in the area indicated by reference number (106). Otherwise, the inner shell (102) extends along the inner wall fertilizer (108) of the outer shell (104). In order to enable easy insertion of a needle, the opening (110) of the inner sleeve (102) has a conical shape.

The embodiment of FIG. 7 corresponds to that of FIG. 5, but in addition to the fluid connection between an outer shell (111) and an inner shell (112), an intimate connection is given, at least in regions, which bears the reference symbol (114).

There is a difference between the exemplary embodiments of FIGS. 10 and 11 in that the inner shell (116) according to FIG. 11 does not protrude beyond the outer shell (118). Otherwise, the same structure can be used both in relation to a funnel-shaped opening (120) of the inner shell (116) and in relation to the intimate connection, i.e. the fusing of materials of the inner shell (116) and outer shell (118) to clearly fix the inner shell ( 116) using the two-component injection molding process.

In the embodiments of FIGS. 12 and 13, an inner shell (122) or (124) extends slightly above an outer shell (126) or (128), that is, it projects beyond this in the front area.

The connection between the inner shell (122) and (124) and the outer shell (126) and (128) is made by positive locking. For this purpose, the inner shell (122) or (124) is provided with projections (130) or (132) which is surrounded by the outer shell (126) or (128).

13 extends along the inner wall of the outer shell (128), the inner shell (122) of the embodiment of FIG. 12 is surrounded by the outer shell (126) in such a way that the front edge area (134) is also covered is. As a result, there is a continuous surface between the inner walls of the inner shell (122) and outer shell (126) without a step or step being formed like a ramp, as is the case in the embodiment of FIG Figure 13 is. The inner shell (124) extends outside the projection (132) along the inner wall (136) of the outer shell (128). In order to ensure simple insertion of the needle into the protective sleeve formed from the inner sleeve (124) and the outer sleeve (128), the inner sleeve (124) has a conically tapering opening (138).

14 and 15 are schematic diagrams to illustrate how a needle guard according to the invention is produced in a two-component injection molding process and then mounted on a needle such as a blood sampling needle.

To manufacture z. B. the needle guard or protective cover (10), a tool block (140) is used, from which domes (142), (144), (146) and (148) protrude, the diameter of which is at least slightly larger than that of the needle (12 ) is.

In the front end region, the domes (142), (144), (146) and (148) have tapered tips, which are provided with the reference numerals (150), (152) by way of example.

The inner casings (28) are sprayed off in a first spraying step. For this purpose, the Do e protrude into hollow cylindrical recesses with appropriate cavities. The tool block (140) is then rotated through 180 ° in order to subsequently spray the outer shells (14).

The finished protective sleeves (10) are then removed from the doors (142) and (144) in order to feed them to a tool (154) via a conveyor.

The tool (154) is equipped in position I with two needles (12), around which needle holders (156) are injected in position II. In a position III, the protective sleeves (10) are fed axially with respect to the longitudinal axes of the needles (12), so that there is a clear central alignment which ensures that the needle tips (24) cannot pierce the inner sleeves (28) . In position IV, the needle guard or the protective cover or cap (10) is connected to the needle holder (156) by spraying, a predetermined breaking point preferably being formed.

Alternatively, there is the possibility that in one tool, which swivels through 180 °, the outer sleeve and needle holder are injected in one cycle.

Claims

Needle guard for a blood sampling needle

Needle protection (10, 48), in particular intended for a blood sampling needle (12), with an outer sheath (14.38.50.73.82.90.94.96, 104, 111, 118, 126) arranged around a needle with a tip , 128), within which at least partially an inner sleeve (28, 36, 52, 68, 80, 86, 92, 102, 112, 116, 122, 124) surrounds the tip of the needle. that the inner shell (28, 36, 52, 68, 80, 86, 92, 102, 112, 116, 122, 124) and the outer shell (14, 38, 50, 73, 82, 90, 94, 96, 104, 111, 118, 126, 128) are parts produced by at least two-component injection molding and that the inner sleeve is secured in the axial direction of the needle (12) by a positive and / or non-positive connection with the outer sleeve.

Needle protection according to claim 1, characterized in that the inner sheath (28, 92, 102, 112, 116) with the outer sheath (14, 98, 104,

111, 118) is fused at least in some areas.

Needle protection according to claim 1 or 2, so that the inner sleeve (36, 68, 80, 124) has at least one protrusion (39, 41, 70,

84, 88) which extends within the outer shell (50, 73, 82, 128). 4. needle guard according to claim 3, characterized in that the projection extends to the outer wall of the outer shell.

5. Needle protection according to at least one of the preceding claims, characterized in that the inner surfaces of the inner and outer sheath (68, 73, 92, 96, 111, 114, 122, 126) are flush.

6. Needle protection according to at least one of the preceding claims, characterized in that the inner sleeve (52, 86, 116, 124) extends along the inner wall of the outer sleeve (50, 90, 118, 128), the inner sleeve having a conically tapering opening (64, 68, 120, 138).

7. Needle protection according to at least one of the preceding claims, characterized in that the inner sleeve (68, 106, 92, 122, 124) extends on the needle tip side over the outer sleeve (73, 104, 96, 126, 128).

8. Needle protection according to at least one of the preceding claims, characterized in that the inner cover, the outer cover and the handle are made in the multi-component injection molding process.

9. Needle protection in particular according to at least one of the preceding claims, characterized in that the protective cover (10) as at least in the region of the needle tip (24)

Magnifier (25) is formed. 10. A method for producing a needle guard (10), in particular intended for a blood sampling needle (12), with an outer sleeve (14) arranged around a needle, an inner sleeve (28) surrounding the tip of the needle running at least in regions within the outer sleeve, thereby I know net that on a dome (142, 144, 146, 148) the inner shell (28) is hosed, that after the inner shell has hardened, the outer shell (14) is hosed down, that after the outer shell has hardened, this with the one unit inner sheath is removed from the dome, that the unit is moved along the longitudinal axis of the needle and connected to this with a needle holder (156) arranged on the needle.

11. The method according to claim 10, d adurch ge e nze i ch n et that the needle holder (156) is made by extrusion coating the needle (12).

12. The method according to claim 10 or 11, dadu rch geken nze net that after the application of the outer shell (14) and the inner shell (28) existing unit is welded to the needle holder (156).

13. The method according to claim 10, dadu rch geke n nze net that the outer shell (14) with the needle holder (156) around the the inner shell (28) holding dome (142, 144, 146, 148) is injected.