Patent · US Expired

High frequency power source for fluorescent lamps and the like

US4005335A · kind A · utility

44Cited by
3References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 15, 1975
Grant dateJan 25, 1977
Priority date
Expiry dateJul 15, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B41/2855
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A power source for operating gas discharge lamps and other loads at high frequency, typically utilizing a 115 volt ac source rectified to provide a 150 volt dc input and providing a 20,000 hertz output. An inverter with a transistor current control for protection against transistor damage under open circuit, starting and no-load conditions, with low power consumption under no-load and with dimming capability. An inverter with a detector circuit connected across the feedback winding or an additional control winding for developing a control signal varying as a function of the feedback winding output, and a zener diode or other device for connecting the control signal to the base of the transistor in current controlling relation when the control signal exceeds a predetermined value.

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