| 摘要 |
An actuator is provided which is adapted, in conjunction with a cartridge, to form a needle-less injector, the cartridge being filled with a liquid to be injected in a subject, and having a liquid outlet and a free piston in contact with the liquid. The actuator comprises an impact member urged by a spring and temporarily restrained by a latch, the impact member being movable in a first direction under the force of the spring to first strike the free piston and then to continue to move the piston in the first direction to expel a dose of liquid through the liquid outlet, the spring providing a built-in energy store. A presure pad surrounds the said liquid outlet and, in use, bears on the subject's skin. The actuator may be formed of two main housing components urged apart by an integral cantilever spring formed on one of them, a safety catch can be provided to prevent inadvertent actuation. |
