Patent ID: 9636455
Date: 2017-05-02
CPC Classifications: A61M,G01F,G16H

Claim:
1. A pump, comprising: a reservoir configured to deliver a liquid; a port coupled to the reservoir and configured to discharge the liquid; a plunger having a piston coupled to a shaft, wherein the piston is disposed within the reservoir in sliding engagement with an inner surface of the reservoir, wherein the piston defines a liquid side of the reservoir and a non-liquid side of the reservoir whereby movement of the plunger towards the liquid side of the reservoir discharges liquid through the port; and a reference-volume assembly coupled to the reservoir, wherein the reference-volume assembly comprises: an actuator coupled to the shaft; a linear position sensor coupled to the shaft and configured to sense a position of the shaft; and a processor operatively coupled to the actuator and the linear position sensor, wherein the processor is configured to estimate a volume of discharged liquid as a function of the position of the shaft.