Controlling system for IC engine

Abstract

A control system of an internal combustion engine includes a timing changing unit that changes opening and closing timing of an intake valve relative to rotation of an output shaft of the engine, a working angle changing unit that changes a working angle of the intake valve, a throttle mechanism including a throttle valve provided in an intake passage of the engine and an actuator that is operable to open and close the throttle valve, and an electronic control unit that controls the timing changing unit, the working angle changing unit and the throttle mechanism so as to control an intake air quantity of the engine to a target intake air quantity. The control system detects a failure of at least one of the timing changing unit, the working angle changing unit and the throttle mechanism, and, upon detection of a failure, executes a selected one of difference fail-safe control processes corresponding to different forms of failures, depending upon the form of the detected failure.

Description

technical field [0001] The present invention relates to a control system of an internal combustion engine installed in an automobile or the like, and more particularly to a failsafe control technique for controlling an intake air amount of an internal combustion engine by using a variable valve mechanism and a throttle mechanism. Background technique [0002] In recent years, an internal combustion engine mounted on an automobile or the like has been developed, which is provided with an electronically controlled throttle mechanism and a variable valve mechanism. In such an internal combustion engine, an electronically controlled throttle mechanism is provided to drive (ie, open and close) the throttle valve by an actuator, and the variable valve mechanism can change opening / closing timing, operating angle, and each intake valve and / or at least one of the lift amount of the exhaust valve. [0003] A known example of an internal combustion engine of the type described above,...

AI Technical Summary

Problems solved by technology

[0004] In the above-mentioned known internal combustion engine, if the variable valve mechanism fails, it becomes difficult to control the intake air amount of the internal combustion engine to the target intake air amount, resulting in poor power performance and exhaust emission quality, which may cause the vehicle equipped with the internal combustion engine difficult to continue driving

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