Rotation position detector using stationary and rotatable disk plates

摘要

A rotation detection apparatus has a first input side disk plate having first and second circumferentially arranged electrodes. An output side second disk plate has electrodes arranged in a circumferential direction to oppose the first plate. One of the disk plates is stationary and one is rotatable. A circuit is provided for supplying a periodic signal of a predetermined period to the first and second electrodes of the first plate. A rotation signal generating circuit is provided for detecting a phase condition between the signal at the electrodes of the second plate and the signal from the periodic signal supplying circuit and generating a rotation signal. A signal transmission device is also provided for transmitting a signal between the rotating plate and the stationary plate.