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:
Aug. 11, 1992
Filed:
Dec. 27, 1990
Ronald W Holling, Lincoln Township, Berrien County, MI (US);
Robert R Williams, Lincoln Township, Berrien County, MI (US);
Whirlpool Corporation, Benton Harbor, MI (US);
Abstract
The present invention is a fault detecting membrane potentiometer keyswitch. The keyswitch includes circuitry for providing a reference voltage signal when not activated, so that a faulty switch can be determined by absence of a reference voltage signal. Specifically, the wiper of the membrane potentiometer keyswitch is coupled to the resistive element of the keyswitch intermediate a sensing portion and a reference portion. With this arrangement, as long as the keyswitch is inoperative, the reference portion provides a reference voltage signal which is distinguishable from any of the setting voltage signals, and also distinguishable from a grounded condition. When a setting signal is observed, a timer is used to determined whether the setting signal is a user entered setting signal or a short between the wiper and the resistive element.