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:
Sep. 17, 1991
Filed:
Jan. 18, 1989
Yasuo Notohara, Hitachi, JP;
Tsunehiro Endo, Hitachioota, JP;
Koujirou Yamashita, Hitachi, JP;
Motoo Futami, Hitachi, JP;
Shigeru Kishi, Oohira, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A power source apparatus has a power factor improving circuit which uses switching elements (4) as buildup transistors. According to the power source apparatus of the present invention, a current carrying ratio of the switching elements is decided to be a value which is obtained by subtracting a number of proportional value of the power source current waveform from the maximum current carrying ratio. Since the device of the present invention does not necessitate a detecting circuit of the power source voltage waveform for outputting an instruction waveform, the circuit thereof is simple and is not affected by the voltage change of the power source and noise generated at the power source.