| 摘要 |
<p>The ampoule fits inside a projectile assembly which can slide axially to and fro in the syringe body. The projectile has a needle which extends through the spring nozzle only when the projectile is advanced in the body. Before this, the projectile is retracted in the body to a loaded position, e.g. by compression of a spring, and can be locked in this position. When the lock is released, the loading force projects the assembly forward to advance the needle through the nozzle. The projectile comprises a cylindrical casing to hold the ampoule. The back end of the casing offers a peripheral abutment to receive. Axial thrust from the projectile loading, e.g. helical compression spring. The casing is pref. made of plastic. Provides injection syringe which automatically inserts the injection needle to a predetermined depth when a trigger is released, positive loading and release for projectile, good centring of needle, glass ampoule protected from damage by loading device.</p> |
