Needle-less injector

Abstract

The invention relates to a needle-less injector having a housing comprising: a chamber defined within said injector for containing liquid to be injected; a liquid outlet for said chamber positioned at the front end of the injector, a dispensing member in contact with the liquid in said chamber and movable in a first direction to reduce the volume of said chamber to cause the liquid contained therein to be expelled through said liquid outlet; drive means for actuating said injector, wherein the dispensing member is a spring-loaded piston movable in said chamber by the spring in the first direction to a preferred position at which the volume of said chamber is at a minimum and the spring is nearly unloaded, and which piston is movable in a second direction opposite to the first direction by actuation of the drive means whilst counteracting a force from the spring and moving the piston to a non-preferred position at which the spring is loaded.

Dependencies are inferred from the claim text.