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. 10, 1999
Filed:
Jun. 24, 1998
Michika Uesugi, Fuji, JP;
Atsuyuki Hiruma, Fujinomiya, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In a direct-current power supply system, an alternating current outputted from an AC power supply is converted by a second diode bridge circuit into a direct current. The direct current is smoothed by voltage doubler capacitors and a smoothing capacitor. A reactor is inserted into an input side of the second diode bridge in series. Detecting circuit is operatively connected to the AC power supply for detecting a zero-crossing point. When the zero-crossing point is detected by the detecting circuit, control means is adapted to firstly switch a switching element on for a first predetermined period of time and, after a predetermined delay period of time has passed since the switching element is firstly switched on, adapted to secondly switch the switching element on for a second predetermined period of time. While the switching element is firstly and secondly switched on, a first diode bridge circuit means is adapted to short-circuit the AC power supply through the reactor so that the AC is forced to flow through the reactor. The rectification means, the short circuit means and the switching element are packaged in one package so that the rectification means, the short circuit means and the switching means are integrated into the one package as one semiconductor module.