Patent · US Expired

Compact fluorescent lamp unit having first and second sealed end portions separated by a support member

US5629586A · kind A · utility

24Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 29, 1995
Grant dateMay 13, 1997
Priority date
Expiry dateJun 29, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/00
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A compact fluorescent lamp unit has a phosphor coated bulb of which first and second sealed end portions. A pair of filaments is disposed in the bulb. The filament contains an emitter for enhancing thermionic emission of electrons therefrom and is caused to be cut off by the self-generated heat when the emitter is substantially dissipated. The lamp device has an inverter circuit containing a resonant capacitor disposed between each one end of the filament coils to pass a resonant current through the capacitor during the operation of the lamp. The filament coil is substantially composed of a tungsten wire having a diameter corresponding to 8 MG though 12 MG and is normally operated with a lamp current ranging from 250 mA to 350 mA. The filament coil has a cold resistance ranging from 2 .OMEGA. to 4 .OMEGA. and an output voltage of the inverter circuit exhibits more than 260 volts when the fluorescent lamp is substituted by a resistor having 5 .OMEGA..

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.