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:
Aug. 27, 1996
Filed:
Apr. 28, 1994
Nobuyoshi Mutoh, Katsuta, JP;
Ryoso Masaki, Hitachi, JP;
Taizou Miyazaki, Hitachi, JP;
Fumio Tajima, Juou-machi, JP;
Tsutomu Ohmae, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The object of the present invention is to provide an electric drive system which ensures effective generation of torque from the start to the maximum speed, and extended cruising distance and upgraded running performances. The drive system according to the present invention is characterized in that, in a electric vehicle to be driven by the wheels which are driven by the rotary output of two or more motors, said two or more motors comprise at least two different types of motors, and the system is provided with the control means to adjust the share of the vehicle driving force to be generated by each of said motors in conformity to the running state of said vehicle. These two or more motors comprise a combination of a low speed drive motor and high speed drive motor, and a highly efficient motor is used as said low speed motor, while a motor having a greater capacity and greater base speed than said low speed drive motor is used as the high speed drive motor. The share of the driving force of said vehicle is controlled by the control means such that up to the maximum torque is generated by said low speed drive motor, with the remaining torque generated by said high speed drive motor.