The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 1989
Filed:
May. 11, 1988
Kabushiki Kaisha Toyota Chuo Kenkyusho, Aichi, JP;
Abstract
A torque detecting apparatus for measuring the amount of magnetostriction of a rotary magnetic material which transmits torque by means of a magnetic sensor, and detecting the transmitted torque on the basis of the measured amount of magnetostriction. The apparatus comprises a magnetic sensor for measuring the amount of magnetostriction of the rotary magnetic material, a demagnetization coil which is opposed to the rotary magnetic material so as to restore the rotary magnetic material magnetized by a disturbing magnetic field to the state of zero magnetization, a demagnetization circuit for applying an oscillating current to the demagnetization coil so as to generate in the rotary magnetic material a periodic damping oscillating magnetic field having the maximum value larger than the coercive force of the rotary magnetic material; and a trigger circuit for outputting a drive timing signal for the demagnetization circuit. The transmitted torque is detected without being influenced by a disturbing magnetic field.