NZ248754A

NZ248754A - Veterinary applicator gun with hydrostatic interconnector to dipspense pill or bolus

Info

Publication number: NZ248754A
Application number: NZ24875493A
Authority: NZ
Inventors: Richard Alan Morton
Original assignee: Simcro Tech Ltd
Priority date: 1993-09-23
Filing date: 1993-09-23
Publication date: 1996-05-28

Description

248754 Patents Form # S * °A .... „V. '8 SEP J994 NEW ZEALAND Patents Act 1953 TOMPLF/ng SPECIFICATION HXL£: Applicator Gun We, Simcro Tech limited Address: 23 Bandon Street, Hamilton, New Zealand Nationality: New Zealand hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: PF05JWP FEE CODE-1050 24 8 7 5 h, APPLICATOR GUN This invention relates to applicator guns and is applicable particularly, but not ^ exclusively, to application guns for inserting a pill, bolus or similar predetermined quantity of material such as medication into the mouth of an animal.

According to one aspect of the invention there is provided an applicator gun, including jq a retainer, to receive and hold a mass of material, a hand-piece connected to the retainer, and actuator means at the hand-piece operable to displace the mass of material from said retainer, in which the actuator means including trigger means adapted, when operated, to move interconnection means to displace the mass from the retainer, in which said interconnection means includes a hydrostatic interconnection operable 15 between the trigger means and the plunger.

The hydrostatic interconnection may include a master piston and cylinder operable by the trigger means and a slave piston and cylinder hydraulically connected to the master ^ piston and cylinder the slave piston and cylinder being connected to move said plunger, the cross sectional area of the master cylinder being greater than the cross sectional area of the slave cylinder.

Conveniently, the ratio of the cross sectional areas of the master cylinder to the slave 25 cylinder is in the region of 7:1.

One embodiment of the present invention is described, by way of example only, with reference to the accompanying drawings, in which: Figure 1. is a side view of an applicator gun, according to the invention.

Figure 2. is a broken longitudinal cross-section of the applicator gun shown in Figure 1.

In the drawings, a handpiece 10 is formed of a pair of mirror-imag 6893FS3. 196/BS/at 24 8 75 mouldings fastened together by screws 11.

A stem 12, conveniently of rigid stainless steel tube is affixed into the handpiece 10 by screws 13. At the end of the stem 12 remote from the handpiece 10, a muzzle 14 is screwed onto the outside of the stem 12. The muzzle 14 is of appropriate size to receive and retain a pill, bolus or similar mass of medication to be introduced into the mouth of an animal. For convenience, the stem 12 is bent downwards through about 15 degrees.

A trigger 15 is pivoted adjacent one end on a pin 16 within the handpiece 10. The trigger 15 has an exposed portion for operation by an operator, and is biased to a starting position by a tension spring 17.

The end of the trigger 15 remote from the exposed portion thereof bears against a piston 18 slidable in a master cylinder 19, which is integral with a slave cylinder in which a slave piston or plunger 20 is slidable. The pistons 18, 20 are sealed within their cylinders by O-rings.

A pusher 21, conveniently in the form of a length of nylon tube is slidable within the stem 12 and at one end is affixed onto an extension 22 of the slave piston 20 and at the other end carries a plug 23 having an enlarged head suitable for pushing the pill or the 25 like from the muzzle 14. The hydrostatic system comprising the master cylinder 19 and slave cylinder is filled with a suitable Hght oil and is sealed by a screwed plug 24.

In operation, the pill or the like is positioned in the muzzle 14, which is then introduced into the mouth of the animal, the trigger 15 is squeezed, which causes the master piston 18 to displace the oil and move the slave piston 20 and correspondingly the pusher 21 and plug 23 towards the left in the drawing, thereby displacing the pill from the muzzle 14. It will be seen that the cross-sectional area of the master cylinder 19 is substantially greater than the cross-sectional area of the slave cylinder, so that movement of the slave ^ piston 20 and of the plug 23 is thereby magnified. Conveniently the mo^emient of the plug 23 is approximately twice the movement of the exposed porti^ps15^ /v * I*, ■ — tJ \19'ahiSSS?I 24 8 / o 4 remote from the pin 14. Topically, the leverage ratio of the trigger 15 about the pin 16 produces a movement of the master piston 18 of around half the corresponding movement of the finger grip of the trigger 15.

The exterior surface of that portion of the stem 12 located within the handpiece 10 is preferably knurled or otherwise roughened, so as to be firmly gripped by integral extensions 25 of the handpiece 10. In addition to the screws 13, the extensions 25 are further clamped and stiffened by a cap 26 screwed onto the threaded exterior thereof. 248754

Claims

WHAT WE CLAIM IS: *

1. An applicator gun, including a retainer, to receive and hold a mass of material, a hand-piece connected to the retainer, and actuator means at the hand-piece operable to displace the mass of material from said retainer, in which the actuator means including trigger means adapted, when operated, to move interconnection means, connected to the trigger means and to a plunger, whereby to displace the mass from the retainer, in which said interconnection means includes a hydrostatic interconnection operable between the trigger means and the plunger.

2. An applicator gun, according to claim 1, in which the hydrostatic interconnection includes a master piston and cylinder operable by the trigger means and a slave piston and cylinder hydraulically connected to the master 15 piston and cylinder, the slave piston and cylinder being connected to move said plunger.

3. An applicator gun, according to claim 2, in which the cross sectional area of the master cylinder is greater than the cross sectional area of the slave cylinder. 20

4. An applicator gun according to claim 3 in which the ratio of the cross sectional areas of the master cylinder to the slave cylinder is in the region of 7:1.

5. An applicator gun according to any of claims 1 to 4 in which the hydrostatic interconnection contains a fixed quantity of liquid sealed therein. 25

6. An applicator gun, according to claim 1, in which the hand-piece and the retainer are affixed on opposite ends of a rigid stem. 30

7. An applicator gun according to claim 6 in which said stem is bent downwards part way along at an angle of around 15 degrees.

8. An appiicaior gun constructed and arranged and adapted to operate substantially as described herein and as shown in the accompanying drawings. 35 % JAMES W PIPER & CO Attorneys for the applicant SIMCRO TECH LIMITED ' 5F^1S9S W 6893AMSP.296/BS/a«