GB2216424A

GB2216424A - A drugging gun

Info

Publication number: GB2216424A
Application number: GB8904925A
Authority: GB
Inventors: Bernard Comminges
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-03-04
Filing date: 1989-03-03
Publication date: 1989-10-11
Anticipated expiration: 2009-03-03
Also published as: NZ228209A; FR2628011B1; AU612467B2; GB8904925D0; FR2628011A1; GB2216424B; AU3018589A

Abstract

The present invention relates to a drugging gun of the type including a body (1) with a mobile handle (5) controlling the longitudinal displacement, inside this body, of a rod (4) entraining a piston (27) slidably mounted in a graduated tank (14) for determining the dose injected by a hollow needle fixed on the tank at the opposite of the body. According to the invention, a plurality of graduated tanks (14) of different volumes may be mounted on the same body. piston (27) being fixed in a removable manner on the end of rod (4) and each tank being fixed to the body with interposition of a member (10-13) forming an adaptor, through which extends the piston rod (4), and including, on the one hand, a fixation member (10) for the end of gun body (1), and on the other hand, at the opposite, a fixation member (13) of the base of tank (14) coaxially to piston rod (4). The invention allows using a main portion of the drugging gun for treatments requiring injection volumes which are very different. <IMAGE>

Description

A DRJSSING GU The present invention relates to so-called drugging guns used for injecting in the mouth of animals veterinary products or similat having a consistence ranging from the fluid consistence to the pasty consistence.

The known drugging guns include a cylindrical tank on one end of which is connected the injection hollow needle, with in this tank a piston mobile under the action of a mobile handle and of springs acting on the piston rod.

According to the nature of the product and of the animal size, the volume of product to be injected may vary from a few milliliters to a hundred and fifty to two hundred milliliters. Therefore, the piston stroke in the tank can be adjusted by various abutment systems limiting the stroke of the piston, and the tank is graduated in volumes as a function of the position of the piston at the beginning of the operation. Since however the piston stroke is limited in practice to about fifty millimeters, one will understand that a sufficiently accurate dosing may only be obtained in practice for doses which can vary without inconvenience within limits separated by about one twentieth of the maximum nominal volume of the tank, that is about five centiliters for a tank of one hundred centiliters.

For this motive, in order to ensure complete treatment ranges, one has to provide for a series of drugging guns with tank volumes ranging between the maximum dose to about twenty times the minimum dose. The drugging guns however are cumbersome apparatus and their multiplication is the cause of practical problems for the user.

The present invention aims at solving this problem and provides a drugging gun of the type including a body with a mobile handle controlling the longitudinal displacement inside this body of a rod entraining a piston slidably mounted inside a graduated tank in order to determine the dose injected by a hollow needle fixed.to tothe tank opposite the body. characterized in that a plurality of graduated tanks of different volumes may be mounted on the same body, whereby the piston is fixed in a removable manner on the end of the rod and each tank is fixed to the body with the interposition of a member forming an adaptor through which extends the piston rod and including on the one hand a member for rigidly connecting it to the end of the gun body, and on the other hand, at the opposite, a fixation member of the base of the tank coaxially to the piston rod.

According to a preferential embodiment, the front end of the gun body is an opened cylinder with an internal screw thread and the adaptor is made of a washer surrounding and guiding the piston rod and forming a bearing surface for the spring threaded onto said rod, whereby said washer carries on one side a threaded sleeve screwed inside the tapped end of the body and, on the other hand, an end-plece with an internal screw thread for receiving the threaded end of the tank corresponding to the adaptor.

According to another embodiment, the front end of the body is in the form of a closed cylinder, the end wall being formed with an orifice for the passage and guiding of the piston rod and forming a bearing surface for the return spring surrounding said rod. The end of the body can be formed with an outer screw thread for receiving the adaptor fixation tapped sleeve or it can be formed with a cylindrical groove, the outer wall of which is tapped for receiving the adaptor fixation threaded sleeve. In these embodiments, the adaptor base may be limited to a junction washer between the fixation sleeves of the adaptor on the body and of the tank on the adaptor.

One may also envisage, within the scope of the invention, a single adaptor, possibly rigidly connected to the gun body and carrying on its face which is opposite to the body a plurality of sleeves which are tapped or have an external screw thread, to the diameters of the different tanks, the periphery of which carries a corresponding outer screw thread or respectively an internal screw thread. One may also provide for a single sleeve with an internal screw thread, the diameter of which corresponds to the threading of the tank of largest diameter, the tanks with the different diameters being prolongated at their base by a peripheral skirt or being provided with an added washer with a threading which is screwed inside the tapped sleeve of the adaptor, the peripheral skirts or washers of the tanks of different volumes having the same diameter.

It is known to provide the drugging guns of this type with an automatic feed by setting in communication the tank via a hollow piston rod with a reserve of product and by mounting check valves between the hollow needle and the tank on the one hand and between the tank and the reserve on the other hand, the recoil motion of the piston sucking the product from the reserve in the tank and the sucked volume being then injected by the hollow needle during the following stage. These guns are however the source of problems resulting from the viscosity of the products which viscosity is the cause of a bad closing of the check valves.The present invention remedies this disadvantage by forming the flaps of the check valves with a frustoconical point carrying an 0-ring bearing on a frustoconical seat coaxial to the flap, the latter being guided by radial ribs having longitudinally the shape of a half-circle bearing on the wall of the flap cylindrical chamber.

The invention is described in more detail hereafter by way of several embodiments, with reference to the accompanying drawings wherein: Fig. 1 is a longitudinal sectional view of the whole drugging gun; Fig. 2 is a sectional detailed view of the adaptor according to a first execution; Fig. 3 is an axial sectional view of the piston; Fig. 4 is a sectional view of a tank; Fig. 5 is a sectional view of the delivery flap between the tank and the hollow needle; Fig. 6 is a corresponding view of the suction flap; Figs. 7 and 8 illustrate alternative embodiments of the end of the gun body; and Figs. 9 and 10 show alternative embodiments of the adaptor.

In the drawings, reference 1 denotes the gun body as a whole, to which body is rigidly connected the front handle 2. On this body 1 is slidably mounted the base 3 of the piston rod 4, said base 3 being rigidly connected to the rear handle 5 sliding in a longitudinal slot 6. A spring 7 pushes base 3 and the piston rod rearwardly, the limit position of the backward stroke being defined by the abutment of handle 5 against a ring 8 screwed on the threaded rear end of body 1.

According to the invention, the fronted of cylindrical body 1 is opened and tapped at 9. In this tapped end is screwed the threaded sleeve 10 of the adaptor, this sleeve being rigidly connected to the washer-shaped body formed with a central passage 12 for the piston rod 4, and on the other face a tapped sleeve 13 having a variable diameter according to the volume of tank 14 which has to be mounted on the gun.

Base 15 of tank 14, which is made of transparent propylene, is threaded, and on the tank wall are engraved in known manner graduations showing the quantity injected when the front edge of the piston is, under the control of ring 8, brought in register with the graduation.

Tank 14 includes a tapped end-piece 16 for receiving the delivery valve 17. This delivery valve includes (Fig. 5) a threaded end-piece 18 which is screwed into the end-piece 16 of the tank, the inner passage of end-piece 18 ending into a frustoconical seat 19. Reference 20 denotes the valve chamber which ends into a tapped end-piece 21 for connecting the hollow needle, not shown. Valve 22 as such includes a frustoconical point 23 with an O-ring 24. It is slidably mounted in the valve chamber via radial ribs 25 the end of which is in the shape of a half-circle in order to authorize the free centering of the frustoconical point 23 on seat 19. The valve is biased so as to bear on its seat by a spring 26.

On the end of piston rod 4 is screwed in a removable manner a piston 27 provided .with an O-ring 28. The piston thus mounted is interchangeable in order to correspond to the diameter of tank 14. The piston is formed with a central orifice 29 setting in communication the tank with the hollow piston rod.

At the rear end of the piston rod is mounted the suction valve 30 (Fig. 6) which includes an end-piece 31 for the fixation on the piston rod and a coupling 32 for the flexible tube leading to the reserve of product. The other constituent elements of valve 30 are identical to those of valve 17 and denoted by the same references.

In Figs. 7 and 8 are shown alternative embodiments of the front end of the gun body 1 involving modifications of the fixation of the adaptor. In these two embodiments, the body front end is closed by a wall 33 formed with a central hole 34 for the passage of the piston rod 4. Therefore, spring 7 bears behind wall 33.

In the embodiment of Fig. 7, the end of the body wall has an overthickness 35 in which is formed a deep cylindrical groove 36 inside which is nested the end of the wall of tank 14. The rigid connection between the tank and the body is provided by a screwed assembly and, as shown, by screwing the screw thread formed on the tank periphery inside the internal screw thread 37 formed in the outer surface of groove 36, or reversely if the tank end is tapped. In the embodiment of Fig. 8, the body end is threaded at 38 for the fixation of the tapped end of the tank wall.

The object of the alternative embodiment of the adaptor shown in Fig. 9 is to have a single adaptor which may receive several tanks of different diameters. The threaded sleeve 10 which is adapted to body 1 is situated on a face of a plaquette 39 forming the adaptor body and having a hole 12 for the passage of the piston rod 4. The other face of plaquette 39 supports a series of tapped sleeves 40 with diameters corresponding to the diameters of the tanks 41 of the series which have to be adapted to the gun. The shape of the pistons 27 for the tanks of different diameters is then adapted so that their rear face nests, in the maximum recoil position, in the sleeves 40 which are inside the corresponding tank.

In the embodiment shown in Fig. 10, the plaquette 42 forming the adaptor body includes a single peripheral sleeve 43 with an internal screw thread corresponding to the screw thread of tank 44 having the maximum diameter of the series. The other tanks 44' of smaller diameters are provided with a peripheral skirt 45 the peripheral wall of which is threaded in order to be screwed inside sleeve 43. Skirts 45 could be replaced by washers or rings which could be screwed on the base of the various tanks and inside sleeve 43.

Claims

1. A drugging gun of the type including a body with a mobile handle controlling the longitudinal displacement inside this body of a rod entraining a piston slidably mounted inside a graduated tank in order to determine the dose injected by a holiov needle fixed to the tank at the opposite of the body, characterized in that a plurality of graduated tanks of different volumes may be mounted on the same body, whereby the piston is fixed in a removable manner on the end of the rod and each tank is fixed to the body with the interposition of a member forming an adaptor through which extends the piston rod and including on the one hand a member for rigidly connecting it to the end of the gun body, and on the other hand, at the opposite, a fixation member of the base of the tank coaxially to the piston rod.

2. A drugging gun according to claim 1, characterized in that the front end of the gun body is an opened cylinder with an internal screw thread and the adaptor is made of a washer surrounding and guiding the piston rod and forming a bearing surface for the spring threaded onto said rod, whereby said washer carries on one side a threaded sleeve screwed inside the tapped end of the body and, on the other hand, an end-piece with an internal screw thread for receiving the threaded end of the tank corresponding to the adaptor.

3. A drugging gun according to claim 1, characterized in that the front end of the body is in the form of a closed cylinder, the end wall being formed with an orifice for the passage and guiding of the piston rod and forming a bearing surface for the return spring surrounding said rod.

4. A drugging gun according to claim 3, characterized in that the end of the body is formed with an outer screw thread for receiving the adaptor fixation tapped sleeve.

5. A drugging gun according to claim 3, characterized in that the end of the body is formed with a cylindrical groove the outer wall of which is tapped for receiving the adaptor fixation threaded sleeve.

6. A drugging gun according to any one of claims 1 to 5, characterized in that it includes a single adaptor with, on its face which is opposite to the body, a plurality of sleeves which are tapped or have an external screw thread, to the diameters of the different tanks the periphery of which carries a corresponding outer or respectively outer screw thread.

7. A drugging gun according to any one of claims 1 to 5, characterized in that it includes a single adaptor with, on the face opposite to body , a single tapped sleeve the diameter of which corresponds to the screw thread of the tank of largest diameter, the tanks with the different diameters being prolongated at their base by a peripheral skirt or being provided with an added washer with a threading which is screwed inside the adaptor tapped sleeve, the peripheral skirts or washers of the tanks of different volumes having the same diameter.

8. A drugging gun according to any one of claims 1 to 7, characterized in that it is of the automatic feed type with check valves having flaps with a frustoconical point carrying an O-ring bearing on a frustoconical seat coaxial to the flap, the latter being guided by radial ribs having longitudinally the shape of a half-circle bearing on the wall of the flap cylindrical chamber.

9. A drugging gun comprising a body adapted to dispense a dose from a tank attached thereto, wherein means are provided for releasably receiving the said tank in order that alternative tanks of varying sizes may be attached to the body.

10. A drugging gun substantially as hereinbefore described with reference to the accompanying drawings.