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. 23, 1996
Filed:
Oct. 25, 1993
Yukihira Sakurai, Tokyo, JP;
Takehiko Ueda, Tokyo, JP;
Kasuga Denki, Incorporated, Tokyo, JP;
Abstract
A controlling apparatus for a high frequency high voltage power source is disclosed which eliminates a switching loss of a high frequency invertor and allows adjustment of the output power to be performed continuously and accurately over a wide range. A resonance current of a resonance circuit of the high frequency high voltage power source is detected by current detection means, and a phase locked loop circuit locks itself with a frequency with which it coincides in phase with the resonance current to produce a synchronized pulse signal. From the pulse signal, a signal having a zero voltage outputting period of a preset duration is formed by a pulse density modulation circuit to change the pattern of a gate signal for switching semiconductor elements of a high frequency invertor to adjust the output power. An input voltage before a zero voltage outputting period is entered is stored into voltage storage means such as a sample and hold circuit so that the phase locked loop circuit may continue to lock with the same frequency also during the zero voltage outputting period.