摘要 |
A preferred example of an injector (1) for needle-less administration of a drug has a rigid member (43) and a conical shell piezoceramic actuator (41) which is anchored to the member (43) around the skirt of the cone. The injector (1) has a pump chamber (54) having an inlet through which a liquid drug can enter and an outlet with a non-return valve (55) through which the liquid drug can be ejected. Operation of the actuator (41) reduces the volume of the pump chamber (54) thereby ejecting a droplet of liquid drug out through the outlet at sufficient speed to pierce a recipient's skin. |