APPAREIL AUTOMATIQUE D'INJECTION DE PRODUITS VETERINAIRES ET SON PROCEDE DE MISE EN OEUVRE

摘要

A pneumatically actuated veterinary syringe for injecting a dose of liq. into the body of an animal. The syringe is part of a portable assembly comprising a syringe with hollow injection needle from a chamber supplied with injection liq. when a syringe valve rod is displaced by its coupling to a pneumatic cylinder. The cylinder contains a piston with automatic spring reset following displacement by compressed air. The assembly comprises a pneumatic switch which is trigger-operated when the needle aperture housing is pressed against the animal. The trigger switch puts regulated air supply pressure on to the entry port of a 'one-shot' metering valve. This is a pneumatic operated valve which delivers a dose of compressed air which is sufficient to displace the piston one only. The air line between trigger switch and one-shot valve pref. branches into a counter which registers batch count and overall period count. Pref. the one-shot valve can be by-passed by a test line incorporating a pneumatic on-off switch. The assembly is compact and can be hand-held. Automatic retraction of the syringe ensures that the needle does not remain in the animal if pneumatics fail. The 'one-shot' device prevents inadvertent double-dosing. The assembly is inexpensive to make and easy to use.