Patent ID: 8988066
Filing Date: 2015-03-24
Classification: G01B,G01D,G01L

Abstract:
1. A sensor circuit for use in conjunction with a rotating shaft assembly mounted in a housing, the shaft assembly having an input shaft, an output shaft and a torsion bar connecting the input shaft to the output shaft, comprising: a CR coil mounted to the housing and disposed annularly around the shaft assembly, said CR coil continuously generating an electromagnetic field when excited by a frequency source, an RX coil mounted to and around one of the input shaft and the output shaft, said RX coil connected to a power circuit to generate power solely from said electromagnetic field from said CR coil when said RX coil is excited by the electromagnetic field from the CR coil, an angle sensor powered by said power circuit and mounted to one of said input shaft and said output shaft, said angle sensor generating a wireless output signal to said CR coil representative of the angle between the input shaft and the output shaft, a sensor output circuit which receives the output signal on said CR coil and generates a sensor signal representative of the angle between the input shaft and the output shaft.