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:
Apr. 12, 1994
Filed:
Jul. 08, 1992
Hirofumi Matsuoka, Souraku, JP;
Hidetoshi Tabuse, Wakayama, JP;
Koyo Seiko Co., Ltd., Osaka, JP;
Abstract
In an electric power steering apparatus which assists a steering power by an electric motor, the difference between currents flowing into and flowing out from the electric motor is obtained, and an abnormality of the electric motor due to a ground fault is detected on the basis of this difference. When a state in which this difference is greater than a given value has continued for a predetermined period of time, the abnormality of the electric motor is detected. Upon the detection of the abnormality of the electric motor, a relay contact of a fail-safe relay circuit is made off so that the supply of electric power from a main power supply to the electric motor is cut off, thereby inhibiting the electric motor from assisting the steering power.