Patent ID: 9155836
Filing Date: 2015-10-13
Classification: A61M

Abstract:
1. An injection device comprising: a) a housing enclosing a product container connected to an injection needle; b) an activating element shiftable relative to the housing from an initial position in which the activating element protects the injection needle to a proximal position to permit manual injection of the injection needle; (c) an advancing member shiftable relative to the housing in an advancing direction, said advancing member comprising a hollow piston rod with a delivery spring fixed thereon, said piston rod acting on a piston to shift it relative to the product container; d) a restoring spring for shifting the activating element distally from the proximal position to an end position; wherein e) the restoring spring has one end supported on the activating element and another end supported on an element connected to the piston rod, such that the restoring spring is tensed by a first amount when the activating element moves from the initial position to the proximal position, and the movement of the advancing member in the advancing direction, driven by relaxation of the delivery spring, simultaneously advances the piston rod for product delivery and moves the element connected to the piston rod in a direction that increases the tension in the restoring spring to cause a force greater than the force initially acting on the activating element.