| 摘要 |
PURPOSE:To prevent the effect of delay in the start of generating negative pressure by a vacuum pump and obtain stable constant running by providing a pump driving means which drives said vacuum pump when the car-speed deviation of the present car speed become above a certain value. CONSTITUTION:At the time of constant speed running, the car speed at that time is compared with one stored in a memory, in an electronic control device 10, and the controlling duty of a control solenoid is determined so as to equalize the difference between them. A vacuum tank 150 is connected to both an intake manifold and the suction port 21 of a vacuum pump 20, through a check valve 160. Car speed deviation is the remainder of a stored car speed from which the present car speed is subtracted and, when the car speed deviation thus counted becomes greater than a constant 1, the vacuum pump 20 is turned on. With a constant 2, which is a smaller value than the constant 1, a negative pressure is fed by the operation of the vacuum pump, to open a throttle and restore the car speed, keeping the pump operating until the car speed is equal to the stored car speed. |
