Idle revolution control device for internal combustion engine.

摘要

An idle revolution control device includes a water temperature sensor (2), a filter means (7) and a control means (7, 9) which is constituted with a central processing unit (7) and an interface (9) connecting the water temperature sensor (2) and the central processing unit (7). The filter means (7) functions to provide a time constant which provide a high response speed for a temperature variation toward a high temperature side and a low response speed for a temperature variation toward a low temperature side and to pass an output signal of the water temperature sensor (2) with such time constant a predetermined time after an engine starts.