Angle measuring device

摘要

An improved angle measuring device in which rotational irregularity in the form of two cycles or more per rotational cycle of the motor driving device is compensated for completely. A period of time T1 required for a cutout formed in the periphery of a rotor rotating at a constant speed to make one revolution starting from a stationary reference point, and a period of time T2 required for the cutout to move between the reference point and an angle measuring point are obtained to evaluate 360 DEG x(T2/T1) to obtain the angle under measurement. The cutout has an angular width of approximately 90 DEG , although angular widths in a range of 5 DEG to 355 DEG can be used as the situation demands.