초록 ▼

A multi-dose infusion pump employs a piston sliding within the internal chamber of a pump housing to dispense liquid from a port. The peripheral surface of the piston has a sequence of steps in a radial pattern spaced at intervals along the longitudinal axis of the chamber. A cap is rotatably mounte

A multi-dose infusion pump employs a piston sliding within the internal chamber of a pump housing to dispense liquid from a port. The peripheral surface of the piston has a sequence of steps in a radial pattern spaced at intervals along the longitudinal axis of the chamber. A cap is rotatably mounted to the pump housing and includes a stop that limits forward movement of the piston by engaging a selected one of the steps on the piston at each rotational position of the cap. This causes a series of predetermined quantities of liquid to be dispensed as the cap is rotated to align the stop with each step in sequence. A spring between the cap and piston urges the piston forward in the chamber to dispense liquid from the port. The peripheral surface of the piston can also be equipped with a series of guide surfaces that allow the piston to be initially retracted toward the cap without engaging the steps while the cap is in an initial rotational position, and then guide the stop along the steps in a predetermined order as the cap is rotated through a progression of rotational positions.

대표청구항 ▼

[ I claim:] [1.] A multi-dose infusion pump comprising:a pump housing having an internal chamber extending along a longitudinal axis and a port for dispensing liquid from said chamber;a piston slidably engaging said chamber of said pump housing and having a peripheral surface;drive means urging said

[ I claim:] [1.] A multi-dose infusion pump comprising:a pump housing having an internal chamber extending along a longitudinal axis and a port for dispensing liquid from said chamber;a piston slidably engaging said chamber of said pump housing and having a peripheral surface;drive means urging said piston along said axis toward said port;a cap rotatably mounted to said pump housing;a plurality of steps spaced at intervals along said axis on one of said piston and said cap; andat least one stop on the other one of said piston and said cap, said stop engaging a selected one of said steps at each of a plurality of rotational positions for said cap, thereby selectively limiting axial movement of said piston toward said port to dispense a predetermined quantity of said liquid, and permitting a series of predetermined quantities of liquid to be dispensed by rotating said cap to align said stop with a sequence of said steps.