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. 21, 1989
Filed:
Jan. 21, 1988
Mark K Goldstein, La Jolla, CA (US);
Earl M Dolnick, Encinitas, CA (US);
Quantum Group, Inc., San Diego, CA (US);
Abstract
A fail safe gas shut off system is provided for a gas appliance. Two normally closed valve stages are provided in series, with each stage operated by a bidirectional solenoid armature. When the armature moves in one direction, the first stage of the valve is opened to supply gas to a pilot burner and to the second stage of the valve. When the pilot flame heats an emissive element to produce sufficient radiation, a photovoltaic device illuminated by the emissive element produces current for an electromagnet which latches the first stage of the valve in its open position. The armature can then move in the opposite direction and open the second stage of the valve to supply gas to the main burner. In the event of pilot flame failure, the emissive element darkens, and current from the photovoltaic device ends. The electromagnet releases the first stage of the valve which is biased closed and cuts off gas flow to both the pilot and main burners.