GB2251553A - Vaccine applicator - Google Patents

Abstract

A vaccine applicator (1<1>) has a container (2<1>) for containing the vaccine which is able to be transferred by the flexing of a diaphragm (8<1>) to a needle (6<1>) which has caused a scratch on an animal's skin. In applying pressure with the needle (6<1>) on the animal's skin to cause the scratch, the plunger (5<1>) is forced rearwardly within its housing (4<1>) which causes the flexing of the diaphragm (8<1>). Subsequent release of the pressure on the animal's skin provides for the further flexing of the diaphragm (8<1>) and the flow of vaccine through the diaphragm slots (9<1>, 18). An optional sponge member (16) can absorb the vaccine and regulate its flow over the plunger (5<1>) and onto the needle (6<1>). <IMAGE>

Description

TITLE: AN APPLICATOR BACKGROUND OF THE INVENTION: The present invention relates to improvements in and relating to applicators.

In particular, but not exclusively, the present invention relates to vaccine applicators of the type where a scratch is made on an animal's skin into which scratch is introduced the required dose of vaccine. Such vaccine applicators are typically used for the application of scabby mouth vaccine to sheep in order to protect against the orf virus.

The present invention will be hereinafter described, by way of simplicity, particularly in respect of such a scratch vaccine applicator but it is to be understood that the present invention in its various embodiments could find application wherever a required dose of a fluid is required to be dispensed. The description hereinafter is therefore to be construed accordingly and alternative and additional applications will be readily apparent to those skilled in the various medical, veterinary and engineering arts for example.

To the present time, scratch vaccine applicators such as described in New Zealand Patent Specification No. 131723 for example, have included a skin scratching means, typically sharpened wire ends, to which one or more droplets of vaccine can be fed by the vaccine container being shaken. The need for such a shaking action makes the operation of such applicators cumbersome, particularly when dealing with a large number of animals which need to be held at the same time. The shaking action also does not lend itself to dispensing an accurate amount of vaccine and the shaking action also can result in air locks preventing or obstructing vaccine flow.

Additionally, in such applicators the sharpened wire ends after several applications frequently become covered in lanoline taken from the sheep's wool, which lanoline tending to block vaccine flow to the scratch and therefore requiring the operator to frequently clean the wire ends.

OBJECTS OF THE INVENTION: It is thus an object of one embodiment of the present invention to provide a scratch vaccine applicator which avoids or at least obviates the above disadvantages in such previously available applicators or at least will provide the public with a useful choice.

Further objects of this invention in all its various embodiments relating to the application of vaccines or other fluids, will become apparent from the following description.

SUMMARY OF THE INVENTION: According to one aspect of the present invention there is thus provided a method of applying a pre-determined amount of fluid to a surface, said method comprising providing a surface engaging means which upon engagement with a surface is moveable relative thereto, providing a valving means so as to be operable upon said movement of said surface engaging means, providing said valving means so as to be in fluid connection with a source of fluid and with said surface engaging means so that upon engagement of said engaging means with said surface, a flexible portion of said valving means is cause to flex causing a required amount of fluid to be drawn through said valving means and forced by a return movement of said flexible portion to said surface engaging means.

According to a further aspect of the present invention there is provided an applicator for applying a fluid to a surface, said applicator comprising a surface engagement means moveable upon engagement with a surface so as to cause the flexing of a flexible portion of a valving means, said valving means being connected or connectable with a source of fluid so that upon engagement of said engagement means with said surface, said flexible portion will be caused to flex, causing a required amount of fluid to flow through said valving means and to be forced by a return movement of said flexible portion to said surface engagement means.

According to a still further aspect of the present invention the applicator defined in the paragraph immediately above comprises a scratch vaccine applicator and said surface engagement means comprises a scratching means provided at a free end of a plunger means, an opposite end of said plunger means being engageable with said flexible portion of said valving means to flex same.

According to a still further aspect of the present invention the scratch vaccine applicator as immediately above defined has said scratching means comprising a pointed end extending outwardly from a substantially regular surface of said free end of said plunger means so as to avoid or substantially reduce the presence of any surfaces which could trap unwanted materials during use.

According to a still further aspect of the present invention there is provided a scratch vaccine applicator substantially as herein described with reference to the accompanying drawings.

Further aspects of this invention which should be considered in all its novel aspects will become apparent from the following description given by way of example of possible embodiments thereof and in which reference is made to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS: Figure 1: shows diagrammatically an exploded view of a scratch vaccine applicator according to one possible embodiment of the invention; Figure 2: shows diagrammatically an exploded view of a scratch vaccine applicator according to a further possible embodiment of the invention; and Figure 2A: shows a side view of the plunger of Figure 2.

Referring to Figure 1 of the accompanying drawings, a scratch vaccine applicator of one possible embodiment of the invention is referenced generally by arrow 1. It is shown comprising a container 2 of any suitable type for containing a supply of the vaccine. Typically the container 2 will comprise a glass or plastic phial and is shown in this embodiment with a screw-threaded neck portion 3.

An applicator head 4, in the example shown, has a commensurate internal thread so that the head 4 can be screwed onto the neck portion 3. The head portion 4 may suitably comprise a plastics moulding for example. A plunger 5 is shown provided with a scratching means 6 at its outer end and in the example shown is illustrated as comprising a pointed end such as a needle or pin. In the illustrated embodiment the needle or pin 6 may be of stainless steel or the like and may be a discrete integer mounted within the end of the plunger 5, the latter which may be a plastics moulding or the like.

Towards the opposite end of the plunger 5 there is shown a valving means referenced generally by arrow 7. In this example, the valving means 7 includes a flexible diaphragm or the like 8 having one or more apertures 9 therein. The apertures 9 in Figure 1 are shown being a pair of elongate slits extending through the diaphragm 8. The valving means 7 in this embodiment is also shown including a chamfered surface 10 provided towards the opposite end of the plunger 5. A projecting portion 11 provides an engagement between the plunger 5 and the diaphragm 8 so that movement of the plunger 5 is translated into a corresponding movement of the diaphragm 8. While in this embodiment a direct contact is shown provided between the plunger 5 and diaphragm 8, it is envisaged that movement of plunger 5 or the like could alternatively be translated into a movement of a diaphragm 8 or the like by some indirect rather than direct connecting means.

The chamfered surface 10 will, in use, and with the needle 6 biassed into its outer most position by the bias provided by the diaphragm 8, seat on a commensurate internal surface 12 provided within the substantially hollow head portion 4. In this position therefore vaccine contained within the container 2 is prevented from travelling to the needle 6.

In use however the needle 6 will be applied to the skin of an animal to create a scratch and the pressure applied to the animal's skin will cause the needle 6 to retract within the head portion 4 against the bias of the diaphragm 8. In doing so the surface 10 will be retracted from its engagement with the valve seat 12 and the diaphragm 8 will also be flexed by the rearward movement of the plunger 5 and the projection 11. It will be seen therefore that once the scratch has been created the pressure on the animal's skin can be gently released which will cause the opposite flexing of the diaphragm 8 drawing vaccine through slits 9, passed the surface 10 and over the plunger 5 to the needle 6 for release onto the scratch.

The end 13 of the head portion 4 is shown provided with an aperture 14 through which the needle 6 projects. With the plunger 5 in its retracted position the vaccine is able to escape through the aperture 4 onto the needle 6. In the embodiment shown such escape of the vaccine can be achieved by a small tolerance being provided between the outer surface of the plunger 5, at least towards its free end at which the needle 6 is positioned, and the diameter of the aperture 14. This tolerance may for example be provided by a slight taper provided for the free end of the plunger 5.

Alternatively the diameter of the plunger 5 may be slightly smaller than the bore through the head portion 4 extending to the aperture 14, along substantially its whole length.

It is seen that by including as part of the valving means 7, a flexible diaphragm 8, the return movement of the diaphragm 8 acts to pump or force the vaccine towards the needle 6 so as to provide a positive flow of vaccine. The amount of vaccine can be determined by the amount of movement allowed for the diaphragm 8 and the size of the one or more slits, openings, or the like 9. This contrasts with the poor and inaccurate release of vaccine provided by the shaking action required by previous types of the applicators.

It will also be seen that the substantially smooth and regular surfaces of the needle 6 and the end of the plunger 5, avoid irregular surfaces which can trap lanoline picked up from the sheep's wool so as to avoid lanoline blockages such as can occur in previous types of applicators.

However, it is envisaged that the tip of the needle 6 may be roughened as this may enhance its scratching function.

In use the diaphragm 8 of Figure 1 will be seated on an internal seat provided about the portion 15 of the head 4, positioned so that it may be engaged by the end 11 of the plunger 5 on its rearward movement and so as to provide a bias against that rearward movement as it itself flexes rearwardly. However it will be apparent to those skilled in the engineering arts that alternative valving means 7 may be provided other than the arrangement as shown of plunger end 10, projection 11 and diaphragm 8. Also, it is envisaged that rather than the flow of the vaccine about the plunger 5 to the scratching means 6 an alternative vaccine flow through a substantially hollow plunger 5 may be provided in alternative embodiments.

Referring now to Figures 2 and 2A of the accompanying drawings an alternative embodiment of the invention referenced generally by arrow 11 is shown reference numerals corresponding to those used in Figure 1 being utilised where appropriate.

The container 21 is shown in this embodiment with a neck portion 31 having peripheral raised portions 20 providing for a push-fit into the hollow end of head portion 41. The valving means 71 is again shown with a diaphragm 81 which in this embodiment is a substantially dish-shaped member with a peripheral rim 19 which with the diaphragm 81 defines a shallow recess at the front and a larger recess at the rear. The diaphragm 81 is shown with a pair of slits 91 but also a pair of flaps 18. It has been found that the provision of these flaps 18, defined by arcuate slits in the diaphragm 81, can enhance the reliability of the flow through the diaphragm 81 as it is flexed without allowing too much flow therethrough. Also in this embodiment the projecting portion 11 engages within an aperture 17 in an absorbent member 16 suitably of sponge.This member 16 once primed with the vaccine has been found to enhance the regulation of vaccine flow through the valving means 71. Once again the chamfered surface 101 of the plunger 51 will seat on a commensurate internal surface 121 of the head portion 41 to normally close off vaccine flow. The front portion 19A of the rim 19 of the diaphragm 81 will seat against an internal seat 15 within the head portion 41. A chamfered edge 22 at the front 31 the neck 1 of the neck 3 of the container 21 can be accommodated within the recess at the rear of the diaphragm 81 to hold the diaphragm 81 in place, biasing the plunger 5 and needle 6 outwardly of the end 131 of the head portion 41.

A cap 21 is shown in this embodiment to fit about the end 131 so as to cover over and protect the needle 61.

Where in the foregoing description reference has been made to specific components or integers of the invention having known equivalents then such equivalents are herein incorporated as if individually set forth.

Although this invention has been described by way of example and with reference to possible embodiments thereof it is to be understood that modifications or improvements may be made thereto without departing from the scope or spirit of the invention as defined in the appended claims.

Claims (11)

1. An applicator for applying a fluid to a surface, said applicator comprising a surface engagement means moveable upon engagement with a surface so as to cause the flexing of a flexible portion of a valving means, said valving means being connected or connectable with a source of fluid so that upon engagement of said engagement means with said surface, said flexible portion will be caused to flex,- causing a required amount of fluid to flow through said valving means and to be forced by a return movement of said flexible portion to said surface engagement means.

2. An applicator as claimed in claim 1 wherein said fluid is a vaccine and said surface engagement means comprising a scratching means provided at a free end of a plunger means, an opposite end of said plunger means being engageable with said flexible portion of said valving means to flex same.

3. An applicator as claimed in Claim 2 wherein said scratching means comprises a pointed end which is biased by said flexible portion of said valving means outwardly from an end of a housing but is caused to retract into said housing, on the pointed end being applied to an animal's skin to cause a scratch, and causing the flexing of said valving means.

4. An applicator as claimed in Claim 3 whereas said valving means comprises a flexible diaphragm having one or more slits therein which on flexing of said diaphragm open out to allow for flow of vaccine therethrough.

5. An applicator as claimed in Claim 4 wherein at least one of said slits is arcuate in shape so as to form a flap.

6. An applicator as claimed in Claim 4 or Claim 5 wherein an absorbent member is provided between said diaphragm and said plunger means so as to absorb vaccine flowing through said diaphragm and to regulate its flow to said plunger means to be transferred to said pointed end.

7. An applicator as claimed in Claim 6 wherein said pointed end extends outwardly from a substantially regular surface of said free end of said plunger means so as to avoid or substantially reduce the presence of any surfaces which could trap unwanted materials during use.

8. An applicator as claimed in any one of Claims 4 to 7 wherein said source of vaccine is a container having a free end engageable with said diaphragm to hold it in place against said plunger means.

9. A method of applying a predetermined amount of fluid to a surface, said method comprising providing a surface engaging means which upon engagement with a surface is moveable relative thereto, providing a valving means so as to be operable upon said movement of said surface engaging means, providing said valving means so as to be in fluid connection with a source of fluid and with said surface engaging means so that upon engagement of said engaging means with said surface, a flexible portion of said valving means is caused to flex causing a required amount of fluid to be drawn through said valving means and forced by a return movement of said flexible portion to said surface engaging means.

10. An applicator substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings.

11. Any novel feature or combination of features described herein.