Patent ID: 6474179
Filing Date: 2002-11-05
Classification: G01L

Abstract:
A torque sensor comprising:a pair of coils having inductances changing mutually in a reverse direction in accordance with a torque; a first differential amplifier means inputting first and second sub-voltages based on each inductance change of the coils, and amplifying a difference between the first and second sub-voltages so as to output the difference as a first main voltage; a second differential amplifier means inputting third and fourth sub-voltages based on each inductance change of the coils, and amplifying a second difference between the third and fourth sub-voltages so as to output the second difference as a second main voltage; and an abnormal state signal outputting means outputting an abnormal state signal when a third difference between the first and second main voltages exceeds a predetermined allowable range, the torque sensor further including: an abnormal state comparator means for judging an abnormal state of the coils from the first, second, third and fourth sub-voltages; and a voltage displacement means for displacing the second main voltage so as to exceed the predetermined allowable range when the abnormal state comparator means makes a decision that an abnormal state occurs, the abnormal state signal outputting means outputting the abnormal state signal when an abnormal state occurs in the coils.