TORQUE DETECTION DEVICE, AND ELECTRIC POWER STEERING DEVICE

摘要

There is provided a torque detecting device for providing a highly accurate torque signal, and an electric power steering device using the torque detecting device. A torque sensor (20) is provided with a first coil pair (22A) and a second coil pair (22B), which detect a relative displacement between an input shaft (2a) and an output shaft (2b) by corresponding the relative displacement to a change in impedance. Magnetization signal generating units (60A, 60B) supply exciting currents with different magnetization frequencies (fl, f2) to the first coil pair (22A) and a second coil pair (22B), respectively. The magnetization frequency difference is set to 3.5 kHz or higher. Moreover, low-pass filters (53A, 53B) for intercepting passage of a frequency equivalent to the magnetization frequency difference are deployed in signal processing circuits (59A, 59B) respectively.