| 摘要 |
PURPOSE:To reduce the external noise of a car only in the running condition of a vehicle when its engine noise is increased to a high level, by decreasing the injection timing of a fuel injection pump only when a speed changer is shifted up to its intermediate speed shift gear increasing the speed of an engine above the prescribed value of rated maximum output speed. CONSTITUTION:The driver drives an engin 4, shifting up the gear position of a speed changer 5 from the first speed to the second speed here fully depressing an accelerator pedal 6, and if a speed of the engine 4 is increased to a level not lower than 3/4 times the maximum output speed, a central processing unit (CPU) 10 feeds a control signal, which opens an oil pressure control valve 14, from the input information from a gear position sensor 2, pedal position sensor 3 and a speed sensor 1 and from the memory information of a memory device 11. The oil pressure control valve 14, operating an actuator 18 by the control signal from the CPU10, delays the injection timing of an injection pump 12 by the prescribed timing. In this way, the external noise of a vehicle is decreased. |
