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. 28, 2009
Filed:
Mar. 21, 2007
Shuichi Matsuhashi, Gunma, JP;
Shuichi Matsuhashi, Gunma, JP;
Japan Servo Co., Ltd., Tokyo, JP;
Abstract
A braking device for an electrically driven rotor comprises a drive signal generating circuit for an electrically driven rotor, an output stage, a motor for the electrically driven rotor, driven by the output stage, and a monitor circuit for detecting interruption of an electric power supply for the motor. The output stage has a MOSFET of an upper stage side and a MOSFET of a lower side, and a diode inserted between a gate of the MOSFET of the lower stage side and the electric power supply. An electromagnetic brake is generated and applied on the electrically driven rotor when the MOSFET of the upper stage side is turned OFF and the MOSFET of the lower stage side is turned ON by a control signal from the monitor circuit, and an exciter coil of the motor is shorted when the electric power supply is interrupted.