Patent ID: 7760850
Filing Date: 2010-07-20
Classification: A61B,G01N

Abstract:
1. An X-ray computed tomographic apparatus comprising: a rotary frame; a mechanism which rotatably supports the rotary frame; an X-ray tube which is mounted to the rotary frame; an X-ray detector which is mounted to the rotary frame; a plurality of rotor magnets which is arranged in the rotary frame; a plurality of stator coils which is opposed to the rotor magnets; a sensor which detects a magnetic-flux variation accompanied by a movement of the rotor magnets; and a position specifying unit which specifies a magnetic-pole position of each rotor magnet with respect to each stator coil on the basis of an output of the sensor and a convergence time from a vibration start of the rotary frame caused by a short-time excitation of the stator coil to a vibration stop of the rotary frame.