US Patent 9872961 Automatic injection device with trigger assembly

Automatic injection device with trigger assembly. The trigger assembly includes a button (25), and a single prong (160) extending from a biased element of the device toward the button. A button-engaging surface (167) of the prong and a support surface of the device define a radially extending opening in which an actuating element (52) of the button fits for a radially outward face of the actuating element to be backed up by the support surface. For release of the biased element, when the button is pressed to shift the actuating element to cause a latching surface of the prong to disengage from a latch surface of the device, motion of the actuating element in a direction away from the prong is limited by the radially outward face of the actuating element abutting the support surface.