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:
Jan. 26, 1988
Filed:
Dec. 01, 1986
Roni K Doak, Houston, TX (US);
Frank Poag, Rosenberg, TX (US);
Other;
Abstract
The electronic monitor includes a level-sensing circuit, a reference circuit, a comparator circuit, and a logic circuit. The level sensing-circuit includes at least one level sensor positioned within the reservoir adjacent to and below a predetermined level. The reference circuit includes a reference sensor positioned in the air adjacent to the maximum allowed level for the material. A current source applies current to all the sensors. The comparator circuit compares the voltage across the reference sensor and the voltage across the level sensor and provides a difference voltage to a logic circuit that activates selective signaling devices depended upon the level of the monitored material. The sensors are preferably negative-coefficient thermistors.