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:
Feb. 20, 1990
Filed:
Jan. 04, 1988
Applicant:
Inventors:
James H Reinholm, Farmington Hills, MI (US);
Dana A Stonerook, Plymouth, MI (US);
Roger A McCurdy, Troy, MI (US);
Assignee:
TRW Inc., Lyndhurst, OH (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08B / ;
U.S. Cl.
CPC ...
340641 ; 307 108 ; 340458 ;
Abstract
The apparatus for driving and monitoring a lamp includes a main drive circuit, a backup drive circuit, a monitoring circuit, all connected to a controller. If the controller determines that the main drive circuit cannot energize the lamp, the backup circuit is enabled to energize the lamp. For purposes of energizing the lamp, the lamp is connectable to one of two electrical ground references. If one of the ground references becomes open circuited from the remainder of the circuitry, then the lamp is energized through the other ground reference.