GB1243574A - Inoculator instrument - Google Patents

Abstract

1,243,574. Hypodermic syringe. O. H. BANKER. 28 April, 1969 [2 May, 1968], No. 21646/69. Heading A5R. A fluid operated inoculator instrument includes an inoculant pump 20 readily disconnectable from a hollow body 10, the pump having a piston rod 30 extending into the hollow body and connected to an operating piston 31 by a quickly releasable means having a control element 46 operable by means extending to the exterior of the inoculator. As described the gun is operated by compressed gas from a bottle 13 in the handle 12 acting on operating piston 31 which engages a shoulder or rod 33 and moves it to the left (as shown) together with pump piston rod 30 carrying pump piston 29 to eject medicament from pump chamber 24 via nozzle orifice 23. The pump 20 is attached to the gun body 10 by bayonet fittings 21. The pump piston rod 30 is releasably secured to hollow operating rod 33 by balls 42 in openings 43 in rod 33 which engage groove 44 in the piston rod 30 and are prevented from moving outwards by control sleeve 46 held in position by spring 49. To release the pump piston rod, pressure on button 54 moves rod 52 to the left engaging pin 47 and moving sleeve 46 to the left against spring 49, and when the portion of sleeve 46 of enlarged inner diameter is above holes 43 the balls may move outwardly releasing piston rod 30. The dose ejected from chamber 24 may be altered by a gauging device 36 which alters the distance of travel in the chamber 24 of piston 29. This is achieved by inserting or removing shims 63 between the end wall 62 of the gun body or a plate 66 on that wall and a flange 35 on the hollow operating rod 33 to limit the distance of travel of that rod. The shims are pivoted on pin 59 and retained in place by nut 64. The shims are preferably hook shaped.