ELECTROSTATIC ROTARY ENCODER

摘要

PURPOSE:To save power along with a lower cost by arranging a rotatable disc- shaped mobile plate and a fixed plate facing it while a plurality of electrostatic electrodes are provided on the periphery of the mobile plate. CONSTITUTION:A rotary encoder has a disc-shaped mobile plate 7 comprising a disc or a circular plate, a plurality of electrostatic capacitance electrodes 8 provided on the periphery of the mobile plate 7 and a fixed plate 9 as opposed to the mobile plate 7 apart therefrom. With such an arrangement, the electrostatic capacitance between the mobile plate 7 and the fixed plate 9 as opposed to each other is detected to allow the elimination of the conventional optical type photo interruptor and magnetic type magnetic head while obviating the need for flowing current through an optical type light emitting diode thereby enabling a power saving design.