FLOW RATE CHARACTERISTICS VARIABLE IDLE ROTATION SPEED CONTROL VALVE

摘要

PURPOSE:To always stabilize idle rotation, by a method wherein one and the same valve body drive shaft is provided with a valve body having characteristics for during cold and a valve body having characteristics for during warm, and the valve body is shifted according to the warming-up state of an internal combustion engine. CONSTITUTION:In an idle rotation speed control valve situated in an intake air flow passage M2 bypassing a throttle valve M1, one and the same valve body drive shaft M3 is provided with a valve body M4 having characteristics for during cold and a valve body M5 having characteristics for during warm. A shifting means M6 shifts the valve body M4 for during cold or the valve body M5 for during warm according to the warming-up state of an internal combustion engine,and only by shifting a motion stroke range, a characteristic patter of a change in an air flow rate is approximately simultaneously shifted, and air flow characteristics responding to respective demands can be obtained throughout a whole opening region. This constitution enables idle rotation to be always stabilized.