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:
Jan. 19, 1993
Filed:
Jul. 19, 1991
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A driving circuit for an inverter microwave oven which includes a push-pull voltage type inverter circuit having two sets of switching element groups each provided with more than two switching elements connected in parallel to each other for switching the D.C. current supplied from a D.C. power source, a control device arranged to set a period for simultaneously turning OFF the two sets of switching element groups and to alternately turn ON the switching element groups by the same duty cycle, a step up transformer supplied, at its primary winding having a center tap, with A.C. current from the inverter circuit, and a voltage doubler rectifier circuit connected to a secondary winding of the step-up transformer for supplying electric power to a magnetron through a capacitor. The driving circuit is set so that one half period of a waveform of current flowing through the switching elements becomes equal to the duty cycle by adjusting the leakage inductance of the step-up transformer, the capacitance value of the capacitor and the circuit resistance of the voltage doubler rectifier circuit or the duty cycle of the switching elements.