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:
Dec. 11, 2001
Filed:
May. 11, 1999
Russell Wilson-Jones, Stratford-Upon-Avon, GB;
John Michael Ironside, Birmingham, GB;
TRW Lucas Varity Electric Steering Limited, West Midlands, GB;
Abstract
A circuit is provided for testing a drive stage of an actuator, such as a motor of an EPAS system. A power supply circuit comprises a contact for supplying normal drive stage current and a resistor for supplying reduced drive stage current before the normal current is supplied. A measuring circuit measures a drive stage electrical parameter such as supply voltage and a comparator compares this with an acceptable value. If the measured parameter corresponds to a current through the drive stage which is different from an expected value, a fault is signaled and the contact is prevented from closing.