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:
Nov. 02, 1999
Filed:
Feb. 25, 1998
Daisuke Bessho, Nara, JP;
Kenji Yasui, Nara, JP;
Yoshiaki Ishio, Nara, JP;
Haruo Suenaga, Katano, JP;
Hideki Omori, Akashi, JP;
Makoto Mihara, Nara, JP;
Kazuho Sakamoto, Kyoto, JP;
Matsushita Electric Industrial Co., Ltd, Osaka, JP;
Abstract
A switching device is employed in a power supply for driving a magnetron with lower withstand voltage and better controllability. A high frequency heating apparatus comprises a power supply, a leakage transformer connected to the power supply, a first switching device connected in series to a primary coil side of the leakage transformer, a first capacitor, a series circuit of a second capacitor and a second switching device, a driving circuit having an oscillator for driving the first switching device and the second switching device, a rectifier connected to a secondary coil side of the leakage transformer, and a magnetron connected to the rectifier. With this configuration, voltage applied to the first switching device can be clamped, and at the same time, the OFF time can be freely adjustable by the effect of the second capacitor and the second semiconductor switching device.