Capacitive rotary angle encoder - contains interleaved stator and rotor plates with conductive surface coatings, one capacitor for excitation of other coarse and fine track to produce sinusoidal functions over full range of 360 deg..

摘要

The encoder contains a stator with separate plates (4,6,8,10) and interleaved rotor plates (5,7,9). The facing stator and rotor surfaces have electrically conducting coatings forming capacitors. Coarse and fine measurement systems are provided by a capacitor whose capacitance varies with rotation. One constant capacitance is independent of rotation. The coatings on the rotor or stator plates are connected in parallel. The constant-value capacitor acts as the excitation capacitor for the other capacitors. The coatings are applied so that the capacitance has a continuous sine or cosine function over the complete 360 deg. angle range. USE/ADVANTAGE - E.g. for use in controlling and positioning moving objects. Angle encoder achieves high resolution with low sensitivity to eccentricities.