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:
Aug. 15, 1989
Filed:
Apr. 06, 1988
Kenichi Onda, Hitachi, JP;
Yasuo Matsuda, Hitachi, JP;
Kojin Abe, Hitachi, JP;
Yasunori Iwafuji, Hitachi, JP;
Hiroyuki Aoyama, Hitachi, JP;
Hideo Yoshinaka, Kumagaya, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Metals, Ltd., Tokyo, JP;
Abstract
An impedance for short-circuit prevention is connected with a secondary winding side of a transformer of a resonant converter comprising a resonant circuit, a D.C. input source, and a switching devices. The short-circuit prevention impedance is driven by the driving current generated in a driving winding in accordance with a resonance current at the primary winding side of the transformer, thereby obviating the stop of an oscillation. The oscillation can be stopped at a timing of not generating a surge voltage in the switching devices by detecting a current returning to the D.C. input power source.