Automatic injection device

摘要

Exemplary embodiments provide a syringe plunger formed of a polymeric material. The syringe plunger includes a pressurizer disposed at a proximal end, and a distal end bifurcated into a first plunger arm having a first conical surface and a second conical surface, and a second plunger arm having a first conical surface and a second conical surface. The distal end includes a first contact surface defined by the first conical surface of the first plunger arm and the first conical surface of the second plunger arm, the first contact surface configured to initially contact a firing engagement mechanism, the first contact surface disposed at a first angle of between about 40° and about 80° relative to a longitudinal axis of the syringe plunger. The distal end also includes a second contact surface defined by the second conical surface of the first plunger arm and the second conical surface of the second plunger arm, the second contact surface configured to contact the firing engagement mechanism subsequent to contact by the first contact surface.

主权项

1. A syringe plunger formed of a polymeric material, the syringe plunger comprising:
a pressurizer disposed at a first end; and a second bifurcated end having a first plunger arm with an end surface, a first transition edge defining an outer perimeter of the end surface of the first plunger arm, a second transition edge, and a third transition edge; and a second plunger arm with an end surface, a first transition edge defining an outer perimeter of the end surface of the second plunger arm, a second transition edge, and a third transition edge, the second bifurcated end including:
a first contact surface defined by a surface between the first transition edge of the first plunger arm and the second transition edge of the first plunger arm and a surface between the first transition edge of the second plunger arm and the second transition edge of the second plunger arm, the first contact surface configured to initially contact a firing engagement mechanism;a second contact surface defined by a surface between the second transition edge of the first plunger arm and the third transition edge of the first plunger arm and a surface between the second transition edge of the second plunger arm and the third transition edge of the second plunger arm, the second contact surface configured to contact the firing engagement mechanism subsequent to contact by the first contact surface.