Dual mode automatic injector

Claim 1

In a spring actuated injector comprising an elongated tubular housing assembly having a forward end adapted to engage a patient and a centrally apertured rear wall, a medicament injecting assembly within the forward end portion of said housing assembly, said medicament injecting assembly including a container, a hypodermic needle, a liquid medicament and a plunger, a stressed spring assembly in the rearward end portion of said housing assembly disposed in operative relation with said medicament injecting assembly for operating the latter so as to move the plunger forwardly within the container, the needle forwardly into a patient, and the liquid medicament outwardly of the needle, said stressed spring assembly including releasable means operable in response to a manual actuating procedure which included the application of a forwardly directed force on said housing assembly while the forward end thereof is in engagement with the patient to release said stressed spring assembly to operate said medicament injection assembly, the improvement which comprises dual mode safety means for preventing the release of said releasable means except when it is desired to operate said medicament injecting assembly, said dual mode safety means including a first part including pin means disposed in safety position extending through the central aperture in said rear wall in release preventing relation with said releasable means for removal therefrom in response to a relative rearward movement with respect to said rear wall so as to permit an actuating movement to release said releasable means, said first part including an automatic mode portion fixed to the rearward end of said pin portion, said automatic mode portion being of a size greater than said pin means but less than said rear wall so as to present a forwardly facing surface spaced rearwardly from said rear wall operable to be engaged by a holding member of an automatic actuating system while a moving member of such system is moved forwardly into engagement with the rear wall to provide both a relative rearward removal movement for said pin means and an actuating movement for said releasable means, said dual mode safety means including a separate second part and connecting means acting between said first and second parts for (1) enabling said second part to be connected with said first part while the pin means of the latter is in said safety position in a manual mode position wherein said first part is in rearward motion transmitting relation to said second part and (2) enabling said second part to be removed from said manual mode position while the pin means of said first part is retained in said safety position, Said second part including a manual mode cap member of a size and shape to be conveniently manually grasped by a user and moved rearwardly with respect to said housing assembly in order to effect the removal of the pin means from said safety position when said second part is in manual mode position.