Patent · US Expired

Circuits for operating discharge lamps

US4179641A · kind A · utility

7Cited by
2References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 9, 1978
Grant dateDec 18, 1979
Priority date
Expiry dateFeb 9, 1998

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S315/07
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electrical circuit for operating an electrical discharge lamp has a pair of terminals for connection to a supply of voltage of substantially sinusoidal waveform, a second pair of terminals for connection with a discharge lamp, a ballast impedance connected between one of the first pair of terminals and one of the second pair of terminals, a starting device for aiding initiation of discharge in the lamp and means for disabling the starting device when a discharge has been initiated in the lamp. The means for disabling the starting device operates in response to a change in the voltage waveform across the second pair of terminals from substantially sinusoidal to substantially square.

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