The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 13, 1997
Filed:
Jun. 29, 1995
Takeo Yasuda, Kanagawa-ken, JP;
Kenichi Asami, Kanagawa-ken, JP;
Toshiba Lighting and Technology Corporation, Tokyo, JP;
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..