PURPOSE: To attain good detection result in low W high frequency bands by attaining an angular position and the relation of signal periods in accordance with relations between plural signals and signals, which are different from these plural signals by 1/2 pitch, when a variation is large, that is, when these plural signals are generated from the same position.
CONSTITUTION: A detector consists of a signal generating auxiliary part 2 provided on a revolving shaft 1, two signal generating parts 3 provided on the side of a still body, and an operation circuit part 4 which processes attained signals. Signals are attained successively from signal generating parts 3 in accordance with the rotation of the shaft 1. If a large variance consisting of an angular displacement exceeding one pitch occurs, two changes of the direction of the angular speed are generated in one period of the variance, and the same signals appear continuously near this change. Consequently, the phenomenon of this continuous appearance of the same signal conditions the inversion of the direction of the angular speed. The operation circuit part 4 has an angular speed direction discriminating circuit.
TANAKA NAOYUKI
MATSUSHITA OSAMI
YONEYAMA MITSUHO
