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:
Jun. 12, 1990
Filed:
Sep. 14, 1989
Other;
Matsushita Electric Works Ltd., Osaka, JP;
Abstract
An inverter power supply with improved power factor comprises a source of low frequency AC voltage and an inverter having a pair of series connected first and second transistors controlled to alternately turn on and off at a high frequency for providing a high frequency AC voltage to a load. A diode-bridge full-wave rectifier is connected to provide a DC voltage which is charged to at least one capacitor which in turn provides a DC voltage input to the inverter. An inductor, which counteracts the capative reactance of the capacitor for improving the power factor, is inserted in series with the AC voltage source across the input of the diode-bridge rectifier. The first and second transistors of the inverter also operate to interrupt or chop at the high frequency a current fed through the inductor from the AC voltage source so as to charge the capacitor through the rectifier by the inductor. During each one cycle of the AC voltage from the AC voltage source, the first and second transistors are both serve to chop the current through the inductor for charging the capacitor as well as to provide the current to the load. Further, the rectifier shares at least two diodes of the inverter for establishing a loop for charging the capacitor.