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. 17, 1989
Filed:
Aug. 07, 1986
Tetsuji Hirotsu, Katsuta, JP;
Kiyoshi Nakamura, Katsuta, JP;
Syoji Kasai, Katsuta, JP;
Hiroshi Yamaguchi, Katsuta, JP;
Eiji Kozu, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The commencement of a developing period of slip is detected by the fact that a time-differential value v.sub.s of a creep velocity v.sub.s (a relative velocity between a peripheral velocity v.sub.m of a driving wheel and a vehicle velocity v.sub.t) exceeds a predetermined reference .delta..sub.1. The termination of the developing period is detected by the fact that a time-differential value v.sub.m of the peripheral velocity v.sub.m becomes equal to zero. During the developing period, a torque command Tp to a main motor controller is decreased by a re-adhesion control signal Tfa which is formed by the combination of a time-dependent component e.sub.1 and a slip-dependent component e.sub.2. After termination of the developing period, the torque command Tp is decreased with time at an appropriate time constant. According to the present invention, the arithmetic logic operation for control can be much simplified without any deterioration of a adhesion performance of an electric vehicle.