PURPOSE: To prevent the rise of the idling speed at the time when trouble is caused with a valve or valves, by driving an actuator for a stopper engaged with an injection quantity control member through opening and closing of a vacuum-controlled valve and a breather valve.
CONSTITUTION: A stopper 5 is disposed within the path of movement of a swing arm 3 connected to an injection quantity control member 2, so as to determined the lower limit value of the injection quantity of the control member 2. A normally closed vacuum-controlled valve 15 and a normally opened breather valve 17 are disposed respectively in a vacuum passage 8 and a breather passage 16, both communicated with an actuator 4 for driving the stopper 5, and operation of these valves 15, 17 is controlled by the signal given from a control circuit 18. With such an arrangement, when a harness connected to the valves 15, 17 is broken, the valve 15 is closed while the valve 17 is opened, so that the vacuum passage 8 is communicated with the atmosphere and the stopper 5 is returned to a position corresponding to the lower limit value of the injection quantity. Therefore, it is enabled to prevent rise of the idling speed.
SAITOU HIDEYUKI
YASUHARA SHIGEFUMI
