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:
Sep. 29, 1998
Filed:
Dec. 27, 1996
Toshimichi Minowa, Toukai-mura, JP;
Hiroshi Kimura, Hitachi, JP;
Yoshiyuki Yoshida, Yokohama, JP;
Yoshishige Ohyama, Katsuta, JP;
Yutaka Nishimura, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A change gear control device is provided for an automatic transmission in a motor vehicle propelled by an internal combustion engine which is operated with an air/fuel mixture having air/fuel ratios ranging from a fuel rich air/fuel ratio to a fuel lean air/fuel ratio depending on driving conditions of the motor vehicle. In this device a first detector detects an engine torque of the internal combustion engine and a second detector detects a vehicle speed of the motor vehicle. A processor processes transmission gear ratios for the automatic transmission. In particular, the processor reads the detected engine torque from the first detector and the detected vehicle speed from the second detector, determines a new transmission gear ratio based upon the engine torque and the vehicle speed, and outputs a signal representing the new transmission gear ratio to the automatic transmission, whereby a gear shifting operation is effected at a timing based on an engine torque variation due to an operating air/fuel ratio change.