Precision scan position resolver for CT scanners

摘要

A scan frame (12) is mounted to a stationary frame (10) for rotation about a scan circle (14). A two speed resolver (20) has one circular core (36) mounted to the gantry and another circular core (32) mounted to the stationary frame. A primary winding (30a, 30b) on one of the cores receives AC excitation power from an excitation generator (58). Quadrature coarse resolution windings (54, 56) and quadrature fine resolution windings (50, 52) both in quadrature produce output signals indicative of the relative angle of the scan frame to the stationary frame. An angular position digitizing circuit (60) converts the analog sine/cosine signals into a digital angle signal.