AU2005202190A1 - Retractable Vaccination Device - Google Patents

Description

P/00/011 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Actual Inventor Address for service is: Eastland Medical Systems Ltd.

Douglas Arthur Sims WRAY ASSOCIATES Level 4, The Quadrant 1 William Street Perth, WA 6000 Attorney code: WR Invention Title: Retractable Vaccination Device The following statement is a full description of this invention, including the best method of performing it known to me:- -2- "Retractable Vaccination Device" Field of the Invention The present invention is directed to a vaccination device, and particularly to such a device where it is not necessary to inject a significant volume of fluid into the patient.

Background Art Vaccination against certain diseases such as small pox requires that the vaccine is introduced to the patient by pricking the skin with a needle which has been dipped into a body of the vaccine and thereby holds small droplets of the vaccine. Typically, for small pox vaccinations, the area of skin is pricked about fourteen times. This task has conventionally been undertaken with a simple needle having a pointed end.

A difficulty which exists in relation to any form of needle used to prick or penetrate the skin is the danger of inadvertent pricking of the user or another person during the assembly and utilisation of the device and its subsequent disposal. Such injuries are often referred to as needle-stick injuries. With the increased awareness of the risk of transmission of disease by needle stick injury, a number of attempts have been made to render the needle of syringes safe after use. Nevertheless, no attempt has previously been made to protect vaccination devices which do not hold a significant quantity of vaccine.

Disclosure of the Invention Accordingly the invention resides in a retractable vaccination device comprising a housing and a needle wherein the needle is adapted to be retained in an exposed, operative position for use and to be fully retracted within said housing after use and wherein the vaccination device further comprises retention means to prevent the needle from being extended from the housing after it has been fully retracted.

-3- According to a preferred feature of the invention, vaccination device is of a type wherein vaccine is stored separately from the device..

According to a preferred feature of the invention, the vaccination device further comprises a slide slidably retained within the housing, said needle being engaged with said slide to be movable therewith, said slide comprising releasable engagement means adapted to engage the housing to thereby retain the needle in said exposed, operative position and releasing means operative on said releasable engagement means to enable the engagement of the slide with the housing to be released upon activation of the releasing means by an operator.

According to a preferred feature of the invention, the vaccination device further comprises a resilient means adapted to urge the slide and needle into a retracted position.

According to a preferred embodiment the resilient means comprises a coil spring through which needle coaxially passes.

According to a preferred feature of the invention, the housing further comprises an orifice through which the needle passes when in said exposed, operative position and wherefrom said needle is withdrawn when in the fully retracted position and wherein said retention means comprises means to orient the needle to prevent alignment of the needle with the aperture when in the needle is in the fully retracted position.

According to a preferred embodiment, the releasable engagement means comprises a tab supported from the slide to engage a retention means associated with the housing.

According to a preferred embodiment, the retention means comprises a notch in the housing adapted to be engaged by the tab.

-4- According to a preferred embodiment, the tab is supported by a resiliently deflectable arm extending from the slide.

According to a preferred embodiment, the housing further comprises a slot extending longitudinally along the housing and the releasing means comprises a knob connected with the arm by a web passing through the slot.

According to a preferred embodiment, the housing further comprises grip means adapted to enable the housing to be gripped by the user for use.

The invention will be more fully understood in light of the following description of several specific embodiments.

Brief Description of the Drawings The description is made with reference to the accompanying drawings of which: Figure 1 is an isometric view of a retractable vaccination device according to the first embodiment showing the device as supplied after the manufacture; Figure 2 is an isometric view of a retractable vaccination device according to the first embodiment showing the device in readiness for use, having its protective sleeve removed; Figure 3 is an exploded view a retractable vaccination device according to the first embodiment; Figure 4 is an isometric view of a retractable vaccination device according to the first embodiment showing the needle in a fully retracted position; Figure 5a is a side elevation of the retractable vaccination device as shown in Figure 1; Figure 5b is a side elevation of the retractable vaccination device as shown in Figure 2; Figure 5c is a side elevation of the retractable vaccination device as shown in Figure 4; Figure 6a is a side elevation of the retractable vaccination device according to the second embodiment showing the device as supplied after the manufacture; Figure 6b is a side elevation of the retractable vaccination device according to a second embodiment showing the device in readiness for use; Figure 6c is a side elevation of the retractable vaccination device according to the second embodiment showing the needle in a fully retracted position; Detailed description of specific embodiments The first embodiment of the invention is directed to a retractable vaccination device as illustrated in Figures 1 to The vaccination device 10 according to the embodiment comprises an elongate housing 20 of substantially square cross-section having an open forward end 21 and an enclosed rearward end 22. The housing 20 is hollow to provide a cavity 23. A first external wall 25 of the housing is provided with a slot 26 penetrating the wall 25 and extending from adjacent the rearward end 22 to the front end 21 of the housing The forward end 21 is waisted and is received by a grip portion 31 to be securely engaged therewith. The grip portion 31 is of generally cuboid form and is provided with a compartment 32 of square cross-section extending from its rearmost face to thereby engage the forward end 21 of the housing 20 to provide a continuous chamber 24. The engagement is secured by use of an adhesive so that the device cannot be disassembled without destroying it.

Two opposed external faces 36 and 37 of the grip portion 31 have a concave profile to enable the grip portion 31 to be clasped firmly by the thumb and -6forefinger of a user. The remaining two faces 38 and 39 of the grip portion 31 are substantially planar.

A cylindrical aperture 40 extends axially into the grip portion 31 from the compartment 32 for a substantial portion of the remaining length of the grip portion 31.

The forward end of the grip portion 31 is provided with a centrally-located, cylindrical nose 34 extending normally, outwardly therefrom. An orifice passes axially through the nose 34 to penetrate into the cylindrical aperture Aperture 40 is of greater diameter than orifice 35 as is discussed below.

The housing 20 and the grip portion 31 are manufactured from a suitable rigid plastics material.

The vaccination device 10 further comprises a needle 14, an actuating slide 16, also of suitable plastics material and a coil spring 18.

The actuating slide 16 comprises a slide body 41 having a cross-sectional profile corresponding with and slightly smaller than the cross-sectional profile of the chamber 24 to enable the actuating slide 16 to slide freely within the chamber 24.

The slide body 41 has a forward face 47 with engagement means adapted to securely engage the needle 14 to retain the needle 14 to the slide body 41. In the embodiment the needle comprises a simple, rigid, stainless steel shaft and the engagement means 48 comprises an axially directed hole extending from the forward face 47 partially into the slide body 41, the secure engagement being achieved by interference fit. According to an alternative adaptation of the embodiment, the needle 14 incorporates an enlarged base member to provide even more secure retention.

The needle 14 is adapted to be moved from a forward, operative position where it passes through the orifice 35 as best shown in Figures 2 and 5b to a fully retracted, safe position as best shown in Figures 4 and 5c. Orifice 35 has a diameter only slightly greater than the diameter of the needle. Aperture 40 is of -7slightly greater diameter than the external diameter of the coil spring and the coil spring 18 coaxially surrounds the needle 14 and is held in compression between the base of aperture 40 and the forward face of the slide body 41 to thereby urge the slide body rearwardly within the housing.

As best shown in Figure 5c, the actuating slide 16 further comprises a latch arm 42 extending rearwardly from the slide body 41. The latch arm 42 comprises an extension of the slide body, having a thickness of approximately half that of the slide body 41 and when assembled disposed on the side of the first external wall At the rearward end of the latch arm 42 there is provided a lock-tab 43 extending transversely outwardly from the latch arm 42. The lock-tab 43 is adapted to engage a notch 44 within the inner surface of first external wall intermediate the rearward end 22 and the forward end 21 of the housing 20. The actuating slide 16 and the lock-tab 43 are dimensioned so that the latch arm 42 is resiliently deflected away from the first external wall 25 because the lock-tab 43 contacts the inner surface of the first external wall 25. When the lock-tab 43 is located at the position of the notch 44 the latch arm 42 relaxes to force the lock-tab 43 to positively engage the notch 44 and thereby retain the actuating slide 16 at a predetermined forward position as shown in Figures 2 and 5b. The actuating slide 16 further comprises an operating knob 45 connected to the latch arm 42 by a web 46 passing through the slot 26 in the first external wall 25. The operating knob 45 is adapted to be pressed by a user to thereby deflect the latch arm 42 by means of the web 46 and thus disengage the lock-tab 43 from the notch 44 so that the actuating slide 16 is forced to move rearwardly by the force applied by the compressed coil spring 18.

As shown in more detail in Figures 5b and 5c, the interaction of the lock-tab 43 with the notch 44 is made more secure by the notch 44 being provided with a rearward face 51 which is sloped rearwardly from the inner surface of the first external wall 25. The rearward face 52 of the lock-tab 43 is also inclined at a corresponding angle. As a result, when the actuating slide is positioned with lock-tab 43 engaging the notch 44, the angled faces of the notch 44 and the locktab 43 cooperate to provide even more secure engagement than would be -8achieved by a notch and lock tab having normal faces. To disengage the locktab 43 from the notch, the actuating slide 16 must be moved forwardly by a small amount against the force applied by the compressed spring, due to the inclination of the engaged faces of the lock-tab 43 and the notch 44. As a result, the user mnust apply a more positive force against the operating knob 45 than would otherwise be required. This has been found to significantly reduce the risk that the lock-tab 43 will be disengaged inadvertently by the user than would otherwise be the case.

In use, the vaccination device 10 of the first embodiment is suppled with the actuating slide 16 in its forward most position, with the lock-tab 43 engaging the notch 44. The needle extending forwardly of the nose 34 is protected by a cylindrical sleeve 19 of plastics material supported by the nose 34, as shown in Figures 1 and During use, the needle is restrained from moving rearwardly by the engagement of the lock-tab 43 with the notch 44 despite the additional force applied to the needle. At completion of use, the user presses the operating knob 45 and the actuating slide 16 is forced rearwardly within the housing 20 by coil spring 18, drawing the needle 14 with it. The length of the needle 14 is such that it is completely withdrawn from the orifice 35 when the actuating slide is moved to its rearmost position. As a result of the resilient deflection of the latch arm 42, a sidewards reactive force is applied to the slide body 41 which tends to cock the slide body 41 and thereby the needle so that they are not quite axially aligned. If the user attempts to move the operating knob 45 forwardly after it has previously been moved fully rearwardly, the misalignment results in the forward end of the needle 14 contacting the base of the aperture 40 of the grip portion 31, rather than passing through the narrow orifice 35. As a result, the needle is securely locked within the housing in a way which positively prevents a user from rendering the device into an unsafe condition from the safe condition. In an alternative adaptation of the embodiment, the needle is of shorter length than that shown in the drawings so that when the actuating slide 16 and needle are fully retracted, the forward tip of the needle is withdrawn right back into the -9chamber 24. In this case, if the user attempts to move the needle forward after it has been fully retracted, the tip will contact the forward face of the compartment 32, again preventing it from entering the orifice The vaccination device according to the first embodiment therefore provides a device for application of a vaccine which is not stored within the device which is simple and effective but may be fully retracted within the housing for safe disposal, After the needle is fully retracted the construction simply but positively prevents the needle from being moved into a dangerous configuration. This arrangement is achieved by a construction which is most cost effective. It is also very suitable for use with multi-point needles.

A second embodiment is shown in Figures 6a to 6c. The second embodiment substantially conforms with the first embodiment and accordingly, in the drawings, like parts are depicted with like numerals.

In the second embodiment, a second notch 61 is provided in the inner face of the first external wall 25 disposed a short distance forward of the rear end 22 of the housing 20. The vaccination device 10 is supplied with the actuating slide 16 positioned so that the lock-tab 43 engages the second notch 61, the second notch being positioned so that the forward end of the needle 14 is positioned within the orifice 35 but not extending from the nose 34. In this embodiment, there is no need for the vaccination device 10 to be suppled with a protective sleeve as was the case for the first embodiment.

When the vaccination device 10 according to the second embodiment is to be used, the user moves the actuating slide 16 and needle 14 forward by means of the operating knob 45 until the lock-tab 43 engages the notch 44, and the device is used in the same manner as for the first embodiment. After use, the actuating slide 16 is moved fully rearwardly so that the needle is withdrawn fully within the chamber and thereby rendered safe in the same manner as for the first embodiment.

The elimination of the need for a protective sleeve provided by the second embodiment further increases the simplicity of construction and reduces the cost of the unit.

It should be appreciated that the scope of the present invention need not be limited to the particular scope of the embodiments described above.

Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Claims (10)

1. A retractable vaccination device comprising a housing and a needle wherein the needle is adapted to be retained in an exposed, operative position for use and to be fully retracted within said housing after use and wherein the vaccination device further comprises retention means to prevent the needle from being extended from the housing after it has been fully retracted.

2. A retractable vaccination device as claimed in claim 1 wherein the vaccination device is of a type wherein vaccine is stored separately from the device..

3. A retractable vaccination device as claimed in claim 1 or claim 2 wherein the vaccination device further comprises a resilient means adapted to urge the slide and needle into a retracted position.

4. A retractable vaccination device as claimed in claim 3 wherein the resilient means comprises a coil spring through which needle coaxially passes. A retractable vaccination device as claimed in any one of the previous claims wherein the housing further comprises an orifice through which the needle passes when in said exposed, operative position and wherefrom said needle is withdrawn when in the fully retracted position and wherein said retention means comprises means to orient the needle to prevent alignment of the needle with the aperture when in the needle is in the fully retracted position.

6. A retractable vaccination device as claimed in any one of the previous claims wherein the vaccination device further comprises a slide slidably retained within the housing, said needle being engaged with said slide to be movable therewith, said slide comprising releasable engagement means adapted to engage the housing to thereby retain the needle in said exposed, operative position and releasing means operative on said releasable engagement means to enable the engagement of the slide with the housing to be released upon activation of the releasing means by an operator. -12-

7. A retractable vaccination device as claimed in claim 6 wherein the releasable engagement means comprises a tab supported from the slide to engage a retention means associated with the housing.

8. A retractable vaccination device as claimed in claim 7 wherein the retention means comprises a notch in the housing adapted to be engaged by the tab.

9. A retractable vaccination device as claimed in claim 7 or claim 8 wherein the tab is supported by a resiliently deflectable arm extending from the slide. retractable vaccination device as claimed in any one of claims 6 to 9 wherein the housing further comprises a slot extending longitudinally along the housing and the releasing means comprises a knob connected with the arm by a web passing through the slot. 11 .A retractable vaccination device as claimed in any one of the previous claims wherein adapted to enable the housing to be gripped by the user for use.

12.A retractable vaccination device substantially as herein described.

13.A retractable vaccination device substantially as herein described with reference to the accompanying drawings. Dated this twentieth day of May 2005. Eastland Medical Systems Ltd. Applicant Wray Associates Perth, Western Australia Patent Attorneys for the Applicant