| 摘要 |
PURPOSE:To enable to lock braking condition and to ease uphill starting, by furnishing a liquid pressure maintaining valve which is closed or opened by a liquid pressure circuit with a magnet and spring, and by controlling electrically its valve with a control circuit depending on operational condition. CONSTITUTION:When a brake pedal 6 is pressed down, a car speed is detected zero by a car speed sensor 22, and the car is in halt condition, a current to the electromagnet 34 of a liquid pressure maintaining valve 14 is cut off. In this case, a valve body 32 sits on a valve seat 31 by the power of a spring 36, the brake liquid in wheel cylinders 17 and 18 is cut off from a master cylin der 5 side, and braking condition is locked. In this position, the car is maintained in the braking condition even though a brake pedal 6 is released. then, a clutch pedal 23 is pressed down, and the gear position of a change gear 21 is changed to the first speed or the back position, the current to the electromagnet 34 is restored, and the braking condition returns to be ordinary.
|
