Cylindrical pushrod for needle-retracting safety injector and the needle-retraction controllable safety injector

Abstract

The invention provide a cylindrical pushrod for the syringe needle-retracting safety injector, comprising an outer cylinder, an inner cylinder, a push pole, an underpinned piece and a seal gasket; the push pole is set at the front end of chamber of outer cylinder, its front end appears as a tubular shape or projects partially in the longitudinal direction, the back end of push pole is supported on the underpinned piece; the underpinned piece is set at the front end of the chamber of outer cylinder and supports the push pole; the cylinder wall of the inner cylinder supports the underpinned piece; a clamping structure is set at the tail of this cylindrical pushrod. With the safety injector with the cylindrical pushrod according to the invention, the medical personnel can control the time of the needle retraction as desired, and is not necessary to change their habitual injection practice, and thereby the safety injector is easy to operate. The invention also provide a safety injector, which can not only carry out the controllable retraction of the needle but also has a simple and crafty fixed structure of the needle stand to achieve the effect of reliable fixation as well as releasing with ease.