AU710557B2 - An applicator - Google Patents

Description

An Applicator Technical Field The present invention relates to devices to deliver medication to animals.

Background of the Invention Currently available applicators are not particularly suited to deliver an extremely accurate and consistent relatively minute volume of a medication to animals. More particularly, previously known devices are not well adapted to deliver such small doses to an abrasion on the skin of an animal.

Disclosed in International Patent Application PCT/NZ95/81 (International Publication No. WO 96/07369) is a scratch vaccine applicator. The applicator receives a vial which delivers vaccine to a scratch blade. Upon the blade being applied to the skin of an animal to scratch the epithelial layer, without completely penetrating the lower ::.:endothelial layer, the vaccine is allowed to flow from the vial to a position adjacent the blade. This device has the same disadvantages of the above discussed applicators, that is is it would not consistently deliver an accurately measured dose of vaccine. A still further disadvantage is that the item is intended to be thrown away rather than the vial merely being replaced.

Object of the Invention 0 OV, 0 It is the object of the present invention to overcome or substantially ameliorate S 20 the above disadvantages.

~Summary of the Invention There is disclosed herein an applicator comprising: .a body to be gripped by a user, including a receiving portion within which a reservoir is to be movably located for movement along a predetermined path, said receiving portion including a first and a second cylindrical surface, which surfaces have parallel longitudinal axes while said first surface has a radius greater than said second surface; a piston member having a first piston portion to cooperate with said first surface to partly enclose a first variable volume chamber, and a second piston portion to cooperate with said second surface to partly enclose a second variable volume chamber, wherein said second chamber extends from said first chamber; [R:LIBLL]08093.doc:MFF [Rs\LIBLLJOSO9J .doc:MFF first duct means extending through said piston member and protruding therefrom to be received within said reservoir to provide for the flow of liquid from the reservoir to said first chamber upon expansion in volume of said first chamber; second duct means extending from said second chamber from which a liquid s dose is delivered upon the reduction in volume of said second chamber; and wherein said receiving portion is positioned relative to said piston so that upon the reservoir being engaged with said first duct means, said reservoir moves with said piston.

In a preferred form there would extend from the piston member a hollow stem to enable air to be delivered to the interior of the reservoir while liquid is withdrawn therefrom.

In a still further preferred form the reservoir would abut the piston member and a user would apply a force to the reservoir to cause reciprocation of the pistom member.

In a still further preferred form the applicator is a scratch vaccine applicator having a scratch blade mounted on said body and to which said second duct means 15 extends to deliver vaccine to a position adjacent the scracth blade.

Brief Description of the Drawings A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein: Figure 1 is a schematic side elevation of an applicator to apply vaccine to an 20 animal; Figure 2 is a schematic part sectioned side elevation of the applicator of Figure 1; V 0 00.0 0*0*0* 0.

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[R:ALIBLLO0O93.doc:MFF Figure 3 is a schematic part sectioned side elevation of the forward portion of the applicator of Figure 1; and Figure 4 is a schematic further part sectioned side elevation of the forward portion of the applicator of Figure 1.

Detailed Description of the Preferred Embodiment In the accompanying drawings there is schematically depicted an applicator which is held in the palm of the hand during use. The applicator 10 includes a body 11 having a handle 12 which is gripped by the user, and a forward portion 13 which receives a reservoir (such as a vial 14) containing a live vaccine. The forward portion 13 is also provided with a scratcher tip 15 including a blade 16. In operation, the blade 16 is passed across the skin of the animal so as to produce an abrasion. The user presses on the vial 14 which causes the vaccine to be delivered via the tip 15. The live S vaccine delivered to broken skin enables the vaccine to enter the animals blood stream.

•Preferably, the vaccine would be delivered to the blade before the skin is scratched.

15 The handle 12 is of a two-part structure so as to have a first part 17 to which !•••"there is pivotally attached a second part 18. The parts 17 and 18 are secured together by means of a hinge 19. The parts 17 and 18 cooperate to provide a cavity in which *extra vials 14 are stored. Still further, the forward portion 13 is provided with cavities in which additional scratcher tips 15 may be stored. Extending from the body 11 is a guard 21 including a projecting portion 22 which is resiliently deflectable, as best seen in Figure 1, from a first position generally covering the blade 16, to a retracted eo.position at which the blade 16 is exposed for use. The projecting portion 22 is deflected upon contact with the skin of the animal. The handle portions 17 and 18 are *pivotally movable from a folded configuration, as shown in Figure 1, to an unfolded position as shown in Figure 2 providing access to the additional vials 14 and additional scraper tips located in the cavities The forward portion 13 provides a cavity 23 within which the vial 14 is mounted and is slidably guided by the walls surrounding the cavity 23. The forward portion 13 is also provided with a cylindrical sleeve 24 providing a cylindrical surface 25. Coaxial with the surface 25 is a further cylindrical surface 26 of smaller radius.

Located between the surfaces 25 and 26 is a seal 27. Cooperating with the cylindrical surfaces 25 and 26 is a piston member 28. The piston member 28 includes a first piston portion 29 which engages and cooperates with the surface 25 to provide a first variable volume chamber 30. Extending from the first piston portion 29 is a second piston portion 31, which cooperates with the cylindrical surface 26 to provide a second variable volume chamber 32. The second piston portion 31 is movable to a position sealingly engaging the seal 29, while the first piston portion is provided with a seal 33 which slidably sealingly engages the cylindrical surface [N:\LIBTT]O0937:exc Surrounding the sleeve 24 is a cavity 34 which receives a spring 35. The spring 35 extends between the forward portion 13 and the piston member 28, urging the piston member 28 to move to a position maximising the volume of the chambers 30 and 32. The forward portion 13 has an annular flange 36 to retain the piston member 28 within the forward portion 13.

Extending from the piston member 28 is a first hollow stem 37, which stem 37 extends to a first passage or duct 38. The passage 38 extends so as to communicate with the first chamber 30. Also extending from the piston member 28 is a second hollow stem 39 which is pointed. The stem 39 extends to a passage 40 containing a one-way valve assembly 41. The valve assembly 41 communicates with the surrounding atmosphere so that in use air is allowed to enter the vial 14 as liquid is withdrawn therefrom. The one-way valve 41 prevents liquid exiting via the passage "The stem 39 has a pointed end to enable the stems 37 and 39 to penetrate a rupturable membrane covering the neck of the vial 14. ooooo 15 Extending from the chamber 32 is a second passage 42 including a one way valve 43. The valve 43 ensures that only liquid moves away from the chamber 32.

Extending from the valve 43 are passages 44 which extend to openings adjacent the blade 16 so that the vaccine is delivered to the blade 16.

The above described preferred form of the present invention, the applicator enables extremely accurate and consistent minute volume doses to be delivered. For i example, 0.01 millilitres can be accurately measured and dispensed after having been directly taken from a vial of 10 to 50 millilitres in volume, containing a live vaccine.

In operation of the above described applicator 10, a user inserts the vial 14 in the cavity 23 so that the stems 37 and 39 pierce the rubber stopper closing the top of the vial 14. A user places the handle 12 in the palm of the hand as illustrated and applies pressure to the end face 44 with the thumb. By pressing down on the end face 44 the spring 35 compresses so that the piston member 28 moves towards the blade 16. This movement causes reduction in the volume of the chambers 30 and 32. Upon the vial 14 being released by the thumb, the spring 35 moves the vial 14 away from the blade 16 so that the volume of the chambers 30 and 32 increases to a maximum. This position is defined by abutment of the piston member with the flange 36. The vaccine in the vial 14 is then drawn into the chambers 30 and 32. This process is repeated until all air is driven from the chambers 30 and 32. When pressure is again applied to the end face 44 to move the piston member 28, vaccine is ejected from the tip 15 when the piston 31 engages the seal 27 and further moves to reduce the volume of the chamber 32.

The one-way valve 41 permits air to enter the interior of the vial 14 as liquid is drained therefrom. The one-way valve 43 ensures that liquid can only flow from the chamber 32 in the direction toward the blade 16 (thereby preventing reverse flow) when the piston member 28 retracts.

[N:\LIBTT100937:exc In the above described embodiment the body 11 includes a handle 12 which is gripped by the user. This arrangement can be modified so that the handle 12 is eliminated. In such an instance the forward portion 13 would be enlarged so that a user may grip the applicator 10 by grasping the forward portion 13.

[N:\LIBTTIOO937:exc 6 The claims defining the invention are as follows: 1. An applicator comprising: a body to be gripped by a user, including a receiving portion within which a reservoir is to be movably located for movement along a predetermined path, said receiving portion including a first and a second cylindrical surface, which surfaces have parallel longitudinal axes while said first surface has a radius greater than said second surface; a piston member having a first piston portion to cooperate with said first surface to partly enclose a first variable volume chamber, and a second piston portion to cooperate with said second surface to partly enclose a second variable volume chamber, wherein said second chamber extends from said first chamber; first duct means extending through said piston member and protruding therefrom to be received within said reservoir to provide for the flow of liquid from the reservoir to said first chamber upon expansion in volume of said first chamber; 15 second duct means extending from said second chamber from which a liquid dose is delivered upon the reduction in volume of said second chamber; and wherein said receiving portion is positioned relative to said piston so that upon the reservoir being engaged with said first duct means, said reservoir moves with said piston.

2. The applicator of claim 1, wherein said first and second surfaces are S 20 coaxial cylindrical surfaces with said second surface having a smaller radius than said first surface.

3. The applicator of claim 1 or 2, wherein said second piston portion moves into sealed cooperation with said second surface when said piston member is *:.moving from its first position to its second position, and said second chamber is open to 25 said first chamber when said piston member is in its first position.

S. 4. The applicator of any one of claims 1 to 3 further including means to deliver air to the interior of the reservoir.

The applicator of any one of claims 1 to 4 further including a valve in said second duct means restricting liquid to flow from said second chamber to a position at which said liquid is ejected from said applicator.

6. The applicator of any one of claims 1 to 5 further including a spring urging said piston member to move from its second position to its first position.

[R:ALIBLL]08093 doo:MFF [R:\LIBLL]08093 doc:MFF

Claims (4)

1. 7. The applicator of any one of claims 1 to 6 wherein said applicator is a scratch vaccine applicator having a scratch blade mounted in said body and to which said second duct means delivers a vaccine drawn from the reservoir.
2. 8. The applicator of claim 7, further including a guard to cover said blade, said guard being movable from a guard position to a position at which the blade is exposed.
3. 9. The applicator of claim 8, wherein said guard is resiliently urged to said guard position. The applicator of any one of claims 1 to 9, wherein said body includes a handle extending from said receiving portion, which handle is to be gripped by a user, said handle being configured relative to said receiving portion that the user's thumb can engage the reservoir to cause movement thereof and therefore movement of the piston.
4. 11. An applicator substantially as hereinbefore described with reference to the accompanying drawings 1 Dated 15 July, 1999 N. J. Phillips Pty. Limited Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON [R:\LIBLL]08093.doc:MFF ABSTRACT An Applicator A vaccine scratch applicator (10) having a body (11) having a handle (12). The body (11) includes a cavity (23) to slidably receive a vial (14) containing the vaccine. The vial (14) engages a piston member (28) to cause reciprocation thereof. Movement of the piston member (28) delivers the vaccine to a position adjacent a scratch blade 16. o *i [N:\LIBTT]00937:exc