TACHOMETER APPARATUS AND METHOD FOR MOTOR VELOCITY MEASUREMENT

摘要

A method and apparatus for determining the velocity of a rotating device is described herein. The apparatus includes a magnet assembly (24) affixed to a rotating shaft (22) of a rotating device (20) and a circuit assembly (30). The circuit assembly includes a circuit interconnection having a sense coil (40) and sensors (34) affixed thereto. The circuit assembly is adapted to be in proximity to the magnet assembly (24), wherein the magnet assembly combines with the circuit assembly to form an air core electric machine such that voltages generated from the sense coil exhibits an amplitude proportional to the velocity.