| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable torque sensor by detecting a contact failure in a contact part between a detecting coil to detect torque and another circuit element. SOLUTION: When a contact failure occurs between a detecting coil 13 (14) and a resistance R1 (R2) and contact resistance is increased, apparent pure resistance is increased in the detecting coil 13 (14), its impedance is increased, and an out-of-phase signal in comparison with the phase of a signal of normal time is outputted from an operational amplifier OP2. The A.C. current of an oscillating part 21 is impressed on the input-side (-) terminal of a comparator CP2, and the output of an operational amplifier OP1 is inputted to the input-side (+) terminal. A phase deviation occurs between the output waveform of the CP2 and the output waveform of the CP1, and the output synthetic waveform of the CP1 and CP2 becomes a rectangular waveform of width corresponding to the phase deviation. As a result, a transistor TR is turned on to inhibit the output of the operational amplifier OP2. |
