Patent · US Expired

Magnetron with full wave bridge inverter

US5012058A · kind A · utility

33Cited by
18References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 1, 1989
Grant dateApr 30, 1991
Priority date
Expiry dateAug 1, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B40/00
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An arrangement for providing power to a cooking magnetron uses a full wave bridge inverter circuit. Four semiconductor switches, pairs of which are switched on and off by a pulse width modulation control circuit provide power to a primary winding of a power transformer. A secondary winding of the power transformer supplies the power to the magnetron. The control circuit switches two of the four transistors on and off by way of an isolated drive circuit such that the control terminals of the semiconductor switches float with respect to the other two semiconductor switches. The control circuit includes pulse width modulation circuitry which provides a control pulse having a width proportional to an input provided across a transconductance amplifier. A signal dependent upon magnetron current is used as part of a feedback loop such that a magnetron current is stabilized against variations due to line voltage changes.

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