Multiple dose injection pen
AssigneeEli Lilly and Company
InventorDale C. Harris
Life of this patent
Estimating the term…
Abstract
The present invention relates to a hypodermic syringe having the same general appearance as a pen which is specifically adapted to provide for multiple measured injections of materials such as insulin or human growth hormone.
Claims17
An improved means for adjustment of the dosage of liquid to be injected from a syringe having a housing for receiving a container of liquid, the container of liquid having a closed first end and a piston closing a second end of the container, the housing having a proximal end and a distal end, the distal end being adapted to receive an injection needle assembly for permitting liquid to pass out of the container first end, a plunger rod, having a noncylindrical cross-section with a first surface, including threads, and a second surface, received within the housing for exerting a force on the piston closing the container second end, the improvement comprising:
- first means received within the housing adjacent the container second end for preventing rotation of the plunger rod in relation to the housing,
- second means engaging a second surface of the plunger rod for restricting movement of the plunger rod toward the housing proximal end,
- third means, used to adjust the dosage of liquid to be injected from the syringe, which means rotatably engages a first surface of the plunger rod for calibrated axial movement with respect to the plunger rod and housing toward the housing proximal end without causing rotation of the housing, and
- fourth means fixed with respect to the housing for stopping any movement of the third means toward the housing distal end at a fixed position relative to the housing.
A syringe having means for adjustment of the dosage of liquid to be injected comprising:
- a housing for receiving a container of liquid, the container of liquid having a closed first end an da piston closing a second end of the container, the housing having a proximal end and a distal end, the distal end being adapted to receive a needle assembly for permitting liquid to pass out of the closed first end of the container,
- a plunger rod received within the housing for exerting a force on the piston closing the second end of the container, the plunger rod having a non-cylindrical cross section, a first surface including threads, and a second surface,
- a collar received within the housing adjacent the container second end, the collar having a non-cylindrical opening corresponding generally to the cross-section of the plunger rod for preventing rotation of the plunger rod with respect to the housing and engaging means engaging the plunger rod second surface for restricting movement of the plunger rod toward the housing proximal end, and
- a hollow cap, used to adjust the dosage of liquid to be injected from the syringe, enveloping the plunger rod end opposite the container and extending outward from the housing proximal end, the cap having a threaded interior surface rotatably engaging the plunger rod first surface portion for calibrated axial adjustment relative thereto, without causing rotation of the housing, and a distal end facing surface for contacting a stop fixed with respect to the housing upon movement of the cap and plunger rod toward the housing distal end.
Dependencies are inferred from the claim text.