Flashing florescent lamps
US4383202A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1980 |
| Grant date | May 10, 1983 |
| Priority date | — |
| Expiry date | Dec 22, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/42
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Fluorescent lamps are flashed by modulating the lamp operating current during a given half-cycle. The other half-cycle operation is unmodulated, thereby resulting in flashing from full lamp brilliance to substantially one-half lamp brilliance. In one embodiment, the modulating circuitry is placed in the line cord providing power to the lamp. The circuitry includes a gated diode and a resistor placed in parallel with each other. A full wave line cord embodiment employs a diode bridge. In another embodiment, the modulating circuitry is placed across the terminals of a conventional fluorescent lamp starter so that current is bypassed around the starter. With this embodiment of the invention, the discharge on half of the cycle is extinguished, but current flows through the lamp electrodes, thereby keeping them hot enough to emit electrons and prevent life-damaging high cathode fall.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.