WO1994009840A1

WO1994009840A1 - Needle protection arrangement

Info

Publication number: WO1994009840A1
Application number: PCT/AU1993/000543
Authority: WO
Inventors: Luigi Luke Pisaniello; Marcel Paul Stephan
Original assignee: Luigi Luke Pisaniello; Marcel Paul Stephan
Priority date: 1992-10-27
Filing date: 1993-10-25
Publication date: 1994-05-11
Also published as: AU5331294A

Abstract

A medical sharp protection device for minimising the risk of accidental injury by medically sharp instruments such as a hypodermic needle. The device consists of a sheath (6) covered by an elastomeric material (10) which covers the needle (2). The sheath (6) can only be retracted over the needle (2) exposing the sharp end of the needle (3) when the sheath (6) and the needle shaft (2) are lined up in one relative angular position, which is not the normal rest state. To achieve this the sheath has to be rotated and the elastic and longitudinal force of the elastomeric material overcome. Since this is an active step the needle can only be exposed by two independent actions. When the elastomeric cover is released the sheath returns to its state of rest in which the sheath connot be exposed without applying a rotation force. The needle sharp end is thus covered preventing personal injury.

Description

NEEDLE PROTECTION ARRANGEMENT

TECHNICAL FIELD

This invention relates to a medical sharps protection arrangement to protect against injury by medical sharp equipment, a typical example being a hypodermic needle.

BACKGROUND ART

Medical sharp instruments, such as hypodermic needles, catheters or scalpels are designed so as to minimise the resistance to their penetration through material whether it be human skin, tissue or plastic caps on bottles. As such, they are inherently very sharp, and pose a safety hazard due to accidental penetration. In addition, a used medical sharp such as a hypodermic needle adds the extra element of danger by virtue of the numerous blood-borne diseases that could be transmitted by accidental penetration.

There are a large number of medical sharp protection and disposal apparatus but none known to the inventors which offer protection immediately before and after use and thus remove the risk of penetration which would normally exist in other protection arrangements during the time when the protection arrangements are removed to allow use of the medical sharp.

In addition, there is a risk that in case of operator error, fatigue, and medical emergency current protection and disposal methods are not implemented thus increasing the hazard of accidental penetration.

DISCLOSURE OF THE INVENTION

Therefore in one form the invention is said to reside in a medical sharp protection arrangement, the medical sharp being of a type having a shank, a tip at one end of the shank and a boss at the other end, the protection arrangement comprising a sheath slidable along the shank and adapted to cover at least the tip of the sharp, a resilient means to bias the sheath to the tip covering position, and an engagement means to prevent the sheath from sliding along the shank unless the sheath is in a selected angular position with respect to the shank.

Preferably the resilient means is mounted to and acts between the boss and the sheath.

Preferably the engagement means comprises a keyhole slot along at least part of the length of the sheath and a corresponding key associated with the shank.

Preferably the key associated with the shank is mounted to the boss and extends along the shank.

In preference the resilient means is a cylindrical elastomeric tube mounted at one end to the boss and at its other end to the sheath.

In preference the sheath extends along about half of the length of the shank.

In preference the resilient means is an elongate elastomeric tube having a closed end, the sheath being fitted into the closed end, the tip of the sharp being adapted to pierce the closed end in use. This allows the determination of whether the medical sharp has been used by simple visual examination of the closed end.

In preference at least a portion of the elastomeric tube is corrugated thereby assisting with provision of rotational as well as longitudinal resiliency.

In preference the corrugations of the elastomeric tube are spiral corrugations.

In preference the elastomeric tube is perforated thereby enabling any air within the elastometric tube to escape when the tube is handled.

In preference the elastomeric tube is transparent enabling visual inspection of the medical sharp.

BRIEF DESCRIPTION OF THE DRAWINGS

This then describes the invention but for a better understanding an embodiment of the invention will now be described with reference to the drawings wherein;

FIG. 1 is a part cross-sectional side view of the arrangement with the resilient means retracted,

FIG.2 is a part cross-sectional side view of the arrangement with the resilient means in position ready for retraction,

FIG.3 is a part cross-sectional side view of the protection arrangement with the resilient means in the engaged position whereby retraction is no longer possible,

FIG 4 shows a part cross-sectional side view of the shank and engagement means formed and extending from the boss and a view from the sharpened first end of the shank,

FIG.5 shows a part cross-sectional side view of the shank cap with end view from both ends of the cap.

FIG.6 is a cross-sectional view on the line 6,6' of Figure 4,

FIG 7 is a cross-sectional view on the line 7,7' of Figure 5, and

FIG. 8 is a cross-sectional view on the line 8,8' of Figure 5.

It is to be understood that the drawings are somewhat schematic in nature and the proportions of the parts do not necessarily reflect an accurate working arrangement.

DETAILED DESCRIPTION OF THE DRAWINGS

The medical sharp in this case a hyperdermic needle 1 is of the type comprising a hollow shank 2 having a first sharpened end 3 for piercing inter alia skin of a patient, and including at a second end a boss 4 for securing the needle to a syringe (not shown). The shank of the needle has an elongate key 5 extending longitudinally along the part of the shank 2, and which stops some way short of the sharpened end or tip of the needle. A sheath 6 in a first, protecting position, as best seen in Fig 3, rests on the top of the elongate key, and covers the sharpened end of the shank.

The sheath 6 includes a generally cylindrical and centrally positioned bore 7 of proportions that allow a sliding along the shank. The bore 7 includes a longitudinal slot 8 which is complementary in shape to the key 5 of the shank as can be seen by comparing Figures 6 and 7 which show respectively the key 5 associated with the shank 2 and the longitudinal slot or keyway 8 in the sheath 6.

The key 5 takes the form of an elongate member extending along the shank and spaced slightly apart from the shank. The key could be formed from the same material that the boss is made of and that is generally of plastics material. Alternatively the key 5 may be fastened to the shank 2.

A elastomeric tube 10 closed at one end is positioned over the sheath with the closed end positioned over the tip of the sheath. The cover is formed of an elastomeric material such as rubber and is positioned close to the shank. The cover engages both the cap and an upper portion of the shank of the needle, and such engagement may be a frictional engagement by reason of the elastomeric material being stretched over the tip of the sheath and the shank.

In use then the needle is provided in a sterile package. On removal from the package the needle is fitted over the mouth of the syringe by frictionally fitting the boss over the syringe. For use the sheath is twisted from a locked position as seen in Fig 3 to an engaged position as seen in Fig 2, so as to align the key of the shank with the keyhole slot of the sheath, and then the sheath is slid along the length of the shank to expose the tip of the needle. In doing so the sharpened end of the medical sharp pierces the rubber cover. When the medical sharp has been used the sheath is released, and returns to its protecting position, by reason of the spring action provided by the elastomeric cover.

The sheath will return automatically to the neutral locked position. The elastomeric cover will ensure that the sheath will also twist back into the locked position. The twisting is assisted by the elastometric cover being of a spiralling corrugated finish which acts to provide both a rotational and longitudinal resiliency and keeps the untwisted sheath in a stable position. In additon the corrugations act to improve the handling and grip of the sheath.

It can be seen therefore that a quite simple means for protecting against needles is provided which obviates or at least minimises the potential for needle personal injury.

Various features of the invention have been particularly shown and described in connection with the illustrated embodiments of the invention, however, it must be understood that these particular arrangements merely illustrate and that the invention is not limited thereto and can include various modifications falling within the spirit and scope of the invention.

Throughout this specification various indications have been given as to the scope of the present invention but the invention is not limited to any one of these but may reside in two or more of these combined together.

Claims

1. A medical sharp protection arrangement, the medical sharp being of a type having a shank, a tip at one end of the shank and a boss at the other end, the protection arrangement comprising a sheath slidable along the shank and adapted to cover at least the tip of the sharp, resilient means to bias the sheath to the tip covering position, and engagement means to prevent the sheath from sliding along the shank unless the sheath is in a selected angular position with respect to the shank.

2. An arrangement as in Claim 1 wherein the resilient means is mounted to and acts between the boss and the sheath.

3. An arrangement means as in Claim 1 wherein the engagement means comprises a keyhole slot along at least part of the length of the sheath and a corresponding key associated with the shank.

4. An arrangement as in Claim 1 wherein the resilient means is a cylindrical elastomeric tube mounted at one end to the boss and at its other end to the sheath.

5. An arrangement as in Claim 1 wherein the sheath extends along about half of the length of the shank.

6. An arrangement as in Claim 1 wherein the resilient means is an elongate elastomeric tube having a closed end (at one end), the sheath being fitted into the closed end, the tip of the sharp being adapted to pierce the closed end in use.

7. An arrangement as in Claim 1 wherein at least a portion of the elastomeric tube is corrugated thereby assisting with provision of rotational as well as longitudinal resiliency.

8. An arrangement as in Claim 1 wherein the key associated with the shank is mounted to the boss and extends along the shank.

9. An arrangement as in Claim 1 wherein the corrugations of the elastomeric tube are of a spiral corrugation.

10. An arrangement as in Claim 1 wherein the elastomeric tube is perforated thereby enabling any air within the tube to escape when the tube is handled.

11. An arrangement as in Claim 6 wherein the elastomeric tube is transparent enabling visual inspection of the medical sharp.

AMENDED CLAIMS

[received by the International bureau on 21 February 1994 (21.02.94); original claims 3 and 8 cancelled; original claims 1, 4-7; and 9-11 replaced by amended claims 1, 3-19; other claim 2 unchanged (2 pages)]

1. A medical sharp protection arrangement, the medical sharp being of a type having a shank, a tip at one end of the shank and a boss at the other end, the protection arrangement comprising a sheath slidable along the shank and adapted to cover at least the tip of the sharp, resilient means to bias the sheath to the tip covering position, and engagement means to prevent the sheath from sliding along the shank unless the sheath is in a selected angular position with respect to the shank, characterised by the engagement means comprising a keyhole slot along at least part of the length of the sheath and a corresponding key mounted to the boss and extending along part of the shank.

2. An arrangement as in Claim 1 wherein the resilient means is mounted at respective ends to and acts between the boss and the sheath.

3. An arrangement as in Claim 1 wherein the resilient means is a cylindrical elastomeric tube mounted at one end to the boss and at its other end to the sheath.

4. An arrangement as in Claim 3 wherein the sheath extends along about half of the length of the shank and the cylindrical elastomeric tube extends between the sheath and the boss over the rest of the length of the shank.

5. An arrangement as in Claim 1 wherein the resilient means is an elongate elastomeric tube having a closed end, the sheath being fitted into the closed end, the tip of the sharp being adapted to extend through the sheath and to pierce the closed end in use.

6. An arrangement as in Claim 1 wherein the resilient means is an elastomeric tube and at least a portion of the elastomeric tube is corrugated thereby assisting with provision of rotational as well as longitudinal resiliency. 7. An arrangement as in Claim 6 wherein the corrugations of the elastomeric tube are in the form of spiral corrugations.

8. An arrangement as in Claim 3 wherein the elastomeric tube is perforated thereby enabling any air within the tube to escape when the tube is handled.

9. An arrangement as in Claim 3 wherein the elastomeric tube is transparent enabling visual inspection of the medical sharp.

STATEMENT UNDER ARTICLE 19

The amendments to the claims restrict their scope to an arrangement not shown in the prior art found in the International Search. The use of a key and associated keyway is new and provides a practical device to use.