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. 05, 1980
Filed:
Aug. 08, 1978
Gordon F Ehret, Alhambra, CA (US);
William N Rowley, Palos Verdes Est., CA (US);
Hermenegildo Espiritu, Cerritos, CA (US);
Wylain, Inc., Dallas, TX (US);
Abstract
A wet-niche type lamp for providing underwater illumination in a swimming pool or the like includes an over-temperature protection circuit which interrupts the supply of electrical energy to the lamp when the level of the cooling water surrounding the lamp drops below a predetermined level. The circuit includes thermistor mounted in an heat exchange relationship with the surrounding water so that heat energy generated in the thermistor, as a consequence of the current flow through it, is normally transferred to the surrounding water. Should the level of the surrounding water drop below that of the thermistor, the thermistor heat energy quickly evaporates any remaining water film on the exterior surface of the thermistor to allow its temperature to rise. The control circuit, in response to the temperature increase, interrupts the flow of electrical energy to the lamp to prevent over-temperature operation.