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:
Sep. 02, 1986
Filed:
Feb. 22, 1985
Thomas P Arbogast, Troy, MI (US);
David Eilola, Southfield, MI (US);
Wickes Manufacturing Company, Southfield, MI (US);
Abstract
A fluid level sensor utilizes thick film thermistors in a four-thermistor bridge configuration. The bridge is heated by a heater to sense the presence or absence of fluid at a particular level with respect to the thermistors. Upon energizing the bridge with a power source, the middle leads thereof are monitored for voltage separation and polarity. An indicator circuit indicates when one or more of the thermistors is submerged in the fluid. The heater influences the temperature of the thermistors to a greater or lesser extent depending upon whether or not they are submerged. Detectable changes in voltages across the bridge are accordingly produced.