Patent ID: 6418798
Filing Date: 2002-07-16
Classification: G01L

Abstract:
An abnormal state detecting apparatus of a torque sensor comprising:a pair of coils whose inductance mutually reverses direction in accordance with a torque; a pair of rectifier circuits respectively connected to said pair of coils; first differential amplifier means inputting the respective outputs of said pair of rectifier circuits as first and second sub-voltages via buffer circuits, amplifying a difference between the first and second sub-voltages and outputting the difference as a first main voltage; second differential amplifier means inputting branch outputs obtained by branching the respective outputs of said pair of rectifier circuits as third and fourth sub-voltages via buffer circuits, amplifying a difference between the third and fourth sub-voltages and outputting the difference as a second main voltage; control means detecting a torque on the basis of the first main voltage corresponding to the output of said first differential amplifier means and diagnosing the first main voltage by means of the second main voltage; memory means storing a corresponding relation between any one sub-voltage selected among said first and third sub-voltages previously calculated in a normal state and any one sub-voltage selected among said second and fourth sub-voltages; and abnormal state judging means inputting a pair of sub-voltage values with respect to said selected pair of sub-voltages and comparing said input pair of sub-voltage values with the corresponding relation of the pair of sub-voltages stored by said memory means so as to judge whether or not an abnormal state exists.