| 摘要 |
PURPOSE:To reduce emission of black smoke and to facilitate control of fuel injection, by advancing the ignition timing by keeping the fuel pressure of an auxiliary injection valve at a constant level, and controlling the auxiliary fuel injection valve according to the operational conditions of an engine. CONSTITUTION:A pulse signal having a frequency proportional to the engine speed and the engine load detected respectively by an engine-speed sensor D1 and a throttle lever opening sensor D2 is applied to a control unit 46, and a control signal S is applied to an electromagnetic injection valve 20 on the basis of said pulse signal. When the opening of a throttle lever becomes greater than a predetermined angle with increasing of the engine load, the injection period is so controlled that fuel is injected from the injection valve 20 at a predetermined rate (10-20%) to the total injection quantity of fuel according to the engine speed. Thus, since pre-flaming reaction is caused before main fuel ejected from a main injection valve 14 is ignited and the ignition of fuel is advanced, emission of black smoke is reduced. Further, since injection of fuel into an intake pipe is effected only at the time of high-load operation of an engine, increasing of HC contained in the exhaust gas is prevented. |
