Three-way compact fluorescent lamp ballast and lamp holder incorporating same
US6072284A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 20, 1998 |
| Grant date | Jun 6, 2000 |
| Priority date | — |
| Expiry date | Jul 20, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A compact fluorescent lamp and an electronic ballast therefor are mounted on a three-terminal base which can be fitted into a three-way-switched standard AC lamp socket, so as to be responsive to the three powered switch positions of the socket for generating three light output levels. The ballast includes an AC-to-DC conversion circuit which supplies a lamp driver including a DC-to-AC conversion circuit, an oscillatory circuit and a resonant circuit. In one embodiment the AC-to-DC conversion circuit includes a full bridge rectifier and a voltage doubler producing two operating voltage levels for the lamp driver and two frequency control voltage levels for the oscillator, the ballast generating three light output levels by using two operating voltages and two operating frequencies. One of the lamp filaments is connected in series with the supply circuit for the oscillator so that the oscillator is inoperative when the lamp is disconnected or its filament burns out, and there is a feedback circuit from the resonant circuit to the oscillator supply for stabilizing its operating frequency. In another embodiment the AC-to-DC conversion circuit includes a half bridge rectifier and two v…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.