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:
May. 19, 1987
Filed:
Jan. 08, 1986
Applicant:
Inventors:
Jack R Volk, Ann Arbor, MI (US);
Philip Piatkowski, Jr, Fraser, MI (US);
Assignee:
Ford Motor Company, Dearborn, MI (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08B / ;
U.S. Cl.
CPC ...
340641 ; 315 82 ; 340 79 ; 3071 / ;
Abstract
A microprocessor circuit employed to control the on/off switching of a filament lamp in series with a power switching device and a single conductor is programmed to periodically cycle the filament lamp between its deenergized and energized state at a rate above that which would be humanly perceptible. A toroidal ferrite core surrounds the conductor between the lamp filament and the switch and picks up current changes which occur due to the cycling. The absence of current changes during cycling are perceived by the microprocessor as a lamp failure and appropriate signaling is made to indicate the lamp failure.