PURPOSE: To restrain variations in the angular speed of a crank shaft to restrain the vibration of an engine, by controlling an intake-air throttling means in accordance with output signals from an air-excess rate detecting means for detecting an air excess rate in exhaust gas and an operating condition detecting means.
CONSTITUTION: Upon starting of an engine, after the opening degree θ0 of an intake-air throttle valve being set, whether the engine is started or not is determined. If the starting is determined, an electrical control circuit 6 which receives output signals from lean sensor 10, a rotational speed sensor 21, a water temperture sensor 11, an intake-air pressure sensor 43, etc. calculates an optimum air excess rate λi in accordance with the rotational speed of the engine, the amount of fuel injection and the temperature of cooling water. Then this air excess rate λi is compared with an actual air excess rate λa, and if λi>λa, a three-way selector valve 72 is controlled to increase the opening degree of the intake-air throttle valve by Δθ, and therefore, an actuator 71 controlls the intake-air throttle valve 42. Meanwhile, if λi<λa, control is made such that the opening degree of the intake-air throttle valve is decreased by.
YASUURA NOBUSHI
TSUZUKI YOSHIHIKO
SUZUKI YUTAKA
| JPS5463459U | 1979-05-04 |