MAGNETOSTRICTIVE STRESS MEASUREMENT APPARATUS

摘要

To simultaneously measure the magnitudes and directions of both axial and torsional stresses produced in a shaft made of magnetostrictive material and provided with first and second sensing segment areas formed in mirror symmetrical arrangement along an outer circumferential surface thereof, the magnetostrictive stress measurement apparatus comprises a first coil provided around the first sensing segment area; a first bridge circuit for detecting change in inductance of the first coil; and a second coil provided around the second sensing segment area; a second bridge circuit for detecting change in inductance of the second coil; and a calculator for calculating an addition of a first inductance change detected by the first bridge circuit and a second inductance change detected by the second bridge circuit to detect an axial stress and a subtraction between the first and second inductance changes to detect a torsional stress.