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. 06, 2007
Filed:
Aug. 25, 2004
Tomoharu Yokouchi, Takatsuki, JP;
Tomoharu Yokouchi, Takatsuki, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A current detecting switching element is connected to an output circuit having switching elements making a bridge connection, current flowing to the switching element is detected by a current detection circuit in response to a torque command signal, a PWM signal generation circuit generates a PWM signal according to the output, a synthesizing circuit synthesizes the output of a power switch circuit for determining an energized phase to a motor coil and the output signal of the PWM signal generation circuit, and PWM operation of a first state and a second state is repeated to control current supply to the motor coil. The first state enables current supply to the motor coil when the switching element on one side is conducting, the switching element on the other side is nonconducting, and the current detecting switching element is conducting. The second state brings the current detecting switching element out of conduction and brings into conduction all the switching elements making a bridge connection in an energizing polarity switch circuit.