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:
Jan. 01, 2008
Filed:
Feb. 16, 2006
Kazuhiro Imaie, Hitachi, JP;
Takashi Yagyu, Ushiku, JP;
Keizo Shimada, Hitachi, JP;
Yasuhiro Kiyofuji, Hitachi, JP;
Naoshi Sugawara, Hitachi, JP;
Kazuhiro Imaie, Hitachi, JP;
Takashi Yagyu, Ushiku, JP;
Keizo Shimada, Hitachi, JP;
Yasuhiro Kiyofuji, Hitachi, JP;
Naoshi Sugawara, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A motor is driven with variable frequency AC power converted from DC power, and an AC output power from the motor is converted to DC. In the conversion, an electromotive force regenerated by the motor is consumed by a plurality of resistors. When the consumption of the electromotive force is impeded in any of systems including any of the plurality of resistors, the electromotive force is consumed by the systems including the remaining resistors. Even if a system including any of the plurality of resistors fails, the electromotive force can by consumed by the other systems including the remaining resistors, thus providing a reliable rheostatic brake.