Patent ID: 11957878
Assignee: BATTELLE MEMORIAL INSTITUTE
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 0:
1. A method of injecting a medicament from a syringe, comprising:
providing a driving force that moves a plunger down the syringe from a distal position toward a proximal position;
wherein a torsion spring is attached at a distal end to a first surface and at a proximal end to a second surface;
wherein the second surface moves with the plunger;
wherein an early stage movement of the plunger toward the proximal position twists the torsion spring to store energy in the torsion spring;
and, subsequently, at a later stage, as the driving force continues to move the plunger toward the proximal position, and the second surface moves with the plunger, the torsion spring rotates through a prescribed path to modify the driving force moving the plunger toward the proximal position.