Starting and operating circuit for arc discharge lamp
US5262699A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 1992 |
| Grant date | Nov 16, 1993 |
| Priority date | — |
| Expiry date | Sep 1, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit for starting and operating a discharge lamp, such as a compact fluorescent lamp, at high frequency from a 60 Hz AC supply. The circuit includes a DC power supply coupled to a pair of AC input terminals for generating a DC voltage. An oscillator coupled to the DC power supply includes a pair of semiconductor transistors and a drive transformer having a primary winding and at least one secondary winding. A load coupled to the output of the oscillator comprises a series combination of the primary winding of the drive transformer and a tank circuit including a tank inductor and a tank capacitor. Suitable means for connecting a discharge lamp in parallel with the tank capacitor is provided. An oscillator sensing and controlling circuit responsive to various lamp failure modes is coupled to the secondary winding of the transformer and reduces the output of the oscillator after a predetermined time delay by shunting the base of either one of the semiconductor switches of the oscillator. Upon replacement of the failed lamp, normal operation of the oscillator is resumed without having to disconnect the AC supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.