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:
Mar. 27, 1990
Filed:
Mar. 31, 1989
Hitachi, Ltd., Tokyo, JP;
Hitachi Automotive Engineering Co., Ltd., Katsuta, JP;
Abstract
Disclosed is a method and apparatus for controlling a throttle valve driven by a D.C. motor in an internal combustion engine, in which the D.C. motor is driven until a valve position sensor detecting the angular position of the throttle valve generates an output signal which coincides with the output signal of an accelerator pedal sensor detecting the amount of depression of an accelerator pedal of a vehicle. The value of motor current required for causing very slight displacement of a return spring provided for returning the throttle valve toward a predetermined angular position is utilized for automatically compensating various factors of fluctuation attributable to friction, inertia, etc. of means driving the throttle valve. A small-capacity microprocessor is used to control the D.C. motor so that the throttle valve can operate with high accuracy and high-speed response capability without being adversely affected by changes in the operating condition as well as secular variations.