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:
Oct. 13, 2009
Filed:
Sep. 27, 2006
Daigo Kaneko, Hitachi, JP;
Takahiro Suzuki, Tokai, JP;
Tsunehiro Endo, Hitachiota, JP;
Kazuaki Tobari, Hitachiota, JP;
Hajime Uematsu, Narashino, JP;
Daigo Kaneko, Hitachi, JP;
Takahiro Suzuki, Tokai, JP;
Tsunehiro Endo, Hitachiota, JP;
Kazuaki Tobari, Hitachiota, JP;
Hajime Uematsu, Narashino, JP;
Hitachi Industrial Equipment Systems Co., Ltd., Tokyo, JP;
Abstract
An apparatus for controlling the drive of an electric motor, having a current detector for detecting the current through an externally connected electric motor; a controller for generating a control signal to control the electric motor on the basis of the current detected by the current detector and the speed command for specifying the rotational speed of the electric motor; wherein the apparatus includes a load estimator for estimating the mechanical load condition associated with the electric motor on the basis of the current detected by the current detector and the speed command, and the controller controls the electric motor current on the basis of the detected current, the speed command and the estimated load condition.