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:
Jul. 16, 1991
Filed:
Mar. 20, 1990
Toshio Mikami, Tsurugashima, JP;
Shigeo Abe, Tsurugashima, JP;
Toko Kabushiki Kaisha, Tokyo, JP;
Abstract
A switching power source having a rectifier circuit and smoothing capacitor for obtaining a d.c. power from an a.c. input, an oscillator circuit constructed of a serial circuit of a primary winding of a power transformer and a switching element for intermittently turning on and off the d.c. power, the power transformer having another winding of the power transformer for detecting the oscillation state of the oscillator circuit, and a rush current preventing circuit constructed of a parallel circuit of a resistor and a thyristor for turning on the thyristor upon reception of a signal from another winding, the rush current preventing circuit being connected at the input side of the rectifier circuit or between the output side of the rectifier circuit and the smoothing capacitor, the switching power source comprising a detector circuit for generating a signal when the interception period of the a.c. input exceeds a first setting time; and an oscillation stopping circuit for stopping the operation of the oscillator circuit for a second setting time in response to the signal from the detector circuit, and when the a.c. input is supplied at the time other than while the operation of the oscillator circuit is being stopped for the second setting time in response to the signal from the detector circuit, directly starting the operation of the oscillator circuit after a lapse of at least the second setting time after the time when the a.c. input was supplied.