Idling speed control system of an internal combustion engine

摘要

PCT No. PCT/JP84/00175 Sec. 371 Date Dec. 7, 1984 Sec. 102(e) Date Dec. 7, 1984 PCT Filed Apr. 7, 1984.The present invention is adapted for providing an idling speed control system of an internal combustion engine, which exhibits a good response for changes in an engine load, comprising: a throttle valve which controls the amount of intake air for the engine; an actuator which includes an electric motor for variably controlling the opening of the throttle valve; a rotation speed detector for detecting the rotation speed of the engine; an idling condition detector for detecting the idling condition of the engine; and a control, responsive to the detected output of the idling condition detector means, for generating feedback control pulses to intermittently drive said electric motor so that the detected rotation speed of the engine under the idling condition may converge into a target idling rotation speed while, responsive to the output of a detector that detects the operation condition of the engine load operated under the idling condition of the engine, or to the detected output of said rotation speed detector indicating that the detected rotation speed has dropped to an abnormally low rotation speed of the engine, for generating drive control pulses at a time independent of said feedback control pulses to drive said electric motor in a predetermined direction.