Patent ID: 8857269
Filing Date: 2014-10-14
Classification: A61M,G01F

Abstract:
1. A medical pump system comprising: a pump including a motor drivingly connected to a pumping mechanism that acts upon a tubing to pump fluid; a controller for controlling the motor to affect operation of the pumping mechanism and vary a fluid flow rate of fluid in the tubing; and a capacitive micromachined ultrasonic transducer sensor assembly operatively coupled to the tubing and in communication with the controller; wherein the controller determines an inner diameter and a wall thickness of the tubing based on a first acoustic signal that bounces off an outer wall and a proximate inner wall of the tubing and is received by the capacitive micromachined ultrasonic transducer sensor assembly; wherein the controller determines a fluid flow velocity of fluid in the tubing based on transit times of generally opposing acoustic signals as the generally opposing second subsequent acoustic signals are sent through the tubing and the fluid in the tubing by the sensor assembly; wherein the controller determines a fluid flow rate of fluid in the tubing based on the determined inner diameter of the tubing and the determined fluid flow velocity of fluid in the tubing; wherein the controller varies the operation of the motor and pumping mechanism to vary the fluid flow rate through the tubing with the pump based on the determined fluid flow rate of fluid in the tubing.