Lamp switching circuit and method
US4766353A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 3, 1987 |
| Grant date | Aug 23, 1988 |
| Priority date | — |
| Expiry date | Apr 3, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A lamp switching circuit and method for selectively energizing one or more lamps of a bank of lamps and thereafter energizing other of the lamps when power is interrupted and next applied. The lamp switching circuit and method is also effective in selectively and sequentially operating one or more ballasts in a group of ballasts which, in turn, operate one or more lamps in a circuit arrangement. The lamps with which the present invention is used are typically phosphor excitable lamps, such as flourescent lamps. In this way, power consumption is reduced, even through lumen output is correspondingly reduced. However, by selectively and sequentially energizing only certain of the lamps in a circuit arrangement, the overall life of the lamps is materially increased. Moreover, the lamps will operate with the same degree of efficiency as they would operate if all lamps connected to a ballast were operating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.