Underwater light assembly with low-water cut-off
US4216411A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1978 |
| Grant date | Aug 5, 1980 |
| Priority date | — |
| Expiry date | Aug 8, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S362/802
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.