An autoinjector comprising an insertion spring acting between a housing and a plunger assembly, a syringe driver, a second release mechanism for releasing the plunger assembly from the housing to cause the insertion spring to move the plunger assembly through the housing together with a syringe driver, a stop feature for blocking movement of the syringe driver beyond a certain point in the housing, a third release mechanism for releasing the plunger assembly from the syringe driver upon its engagement with the stop feature to allow the plunger assembly to continue progressing through the housing. Said first release mechanism is configured to release the plunger from the delivery spring housing upon contact between the plunger assembly and a bung, to cause the delivery spring to drive separation of the delivery spring housing and the plunger and to thereby apply a delivery force to a bung. The device further comprises a latch mechanism for latching the delivery spring housing at a forward position to substantially prevent rearward movement of the delivery spring housing within the housing following release of the plunger from the delivery spring housing.一種自我注入器，包括作用於殼體與柱塞配件之間的插入彈簧，注射器驅動件，用於從殼體上釋放柱塞配件、以使插入彈簧連同注射器驅動件一起移動柱塞配件通過殼體的第二釋放機制，用於阻止注射器驅動件的移動超出殼體中的某個點的止動特徵件，第三釋放機制， 用於在與止動特徵件嚙合的時候從注射器驅動件上釋放柱塞配件，以便允許柱塞配件繼續通過殼體前進。 所述第一釋放機制被配置成在柱塞配件與塞子相接觸時從輸送彈簧殼體上釋放柱塞，以使輸送彈簧驅動輸送彈簧殼體與柱塞分離，並且由此對塞子施加輸送力。 該設備進一步包括閂鎖機制，用於將輸送彈簧殼體鎖在前部位置，由此在從輸送彈簧殼體上釋放了柱塞之後基本上防止輸送彈簧殼體在殼體內部向後移動。
