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:
Mar. 11, 2003
Filed:
May. 11, 2001
Hiroto Ohishi, Kanagawa, JP;
Jiro Oouchi, Miyagi, JP;
Other;
Abstract
A fixing device for an image forming apparatus includes an inverter circuit for induction heating. In the inverter circuit, a main switch Q drives one end of a work coil L whose other end is connected to a power source. A serial connection of a capacitor Cs and a subswitch Q is connected to opposite ends of the coil L in parallel such that one end of the capacitor Cs is connected to the power source E. A second capacitor C is connected to the subswitch Q in parallel. For a capacitance of 0.1 &mgr;F of the capacitor C , the factor of the coil L and that of the capacitor Cs are selected to be between 70 &mgr;H and 100 &mgr;H and between 1.8 &mgr;F and 5 &mgr;F, respectively. The inverter circuit is operable with optimal efficiency in the event of PWM (Pulse Width Modulation) control using a fixed frequency.