Patent ID: 11904143
Assignee: AMGEN INC.
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 0:
1. An injector comprising:
a housing having a syringe assembly and an actuating mechanism at least partially disposed within the housing,
the syringe assembly including:
a syringe barrel having a first end, a second end, and a longitudinal axis, the syringe barrel adapted to store a medicament for patient administration, and
a needle assembly coupled to the second end of the syringe barrel, the needle assembly having a needle hub and a needle attached thereto,

the actuating mechanism being operatively coupled to the syringe assembly and including:
a frame member disposed within the housing, the frame member having a threaded opening formed between a first surface and a second surface,
a plunger assembly comprising a threaded plunger rod and a plunger face, the threaded plunger rod threadably coupled to the threaded opening of the frame member, the plunger face being disposed near the first end of the syringe barrel, the plunger assembly being moveable along the longitudinal axis of the syringe barrel,
a plunger rod guide coupled to the plunger assembly to maintain alignment between at least the frame member and the plunger assembly, and
a torque spring configured to exert a torque and cause relative rotation between at least one of (a) the plunger assembly and the frame member or (b) the plunger rod guide and the frame member, wherein relative rotation causes the plunger assembly to advance towards the syringe barrel to urge the medicament through the needle assembly.