| 摘要 |
PURPOSE:To maintain a necessary constant vacuum in device in which a vacuum source is ensured by a vacuum pump driven by a d.c. motor when vacuum in manifold is insufficient, by controlling the motor in accordance with detected vacuum pressures. CONSTITUTION:A constant speed control device comprises a d.c. motor 1, a vacuum pump 2 directly coupled with the motor 1, an accumulator 3 storing vacuum generated in the pump 2, a vacuum regulator 4 for controlling vacuum pressure from the accumulator 3, an actuator 5 for driving a throttle valve with the regulated pressure, etc. Further, a check-valve 7 is disposed in a pipe line through which pressure is introduced from an intake manifold 10. Further, the vacuum source of the vacuum regulator 4 is maintained at a constant pressure by controlling the rotational speed of the d.c. motor 1 in accordance with vacuum of the above-mentioned accumulator 3 detected by a detector 11. With this arrangement, a constant vacuum pressure may be obtained in the accumulator 3 irrespective of engine loads, and therefore, the vehicle speed may be controlled to be constant. |
