| 摘要 |
PURPOSE:To avoid unstable behavior and delay in braking a vehicle by braking on regeneration-priority mode during ordinary operation and repeating opening and closing the rear-wheel bypass valves rapidly, in order to boost hydraulic pressure on the rear wheels when the front wheels have a high slip ratio. CONSTITUTION:Front wheels (Fr) are driven with an electric motor 2 and rear wheels (Rr) idle. Each wheel is provided with a wheel cylinder 5 for hydraulic braking. The front wheels (Fr) are also subjected to regenerative braking. A hydraulic pressure generated in a brake master cylinder 4 according to a tread on a brake pedal 21 is fed to pipings 61, 62, and then to the (Fr) and Rr through relief valves 6, 56, and by-pass valves 7, 52, 53. The Rr is provided with a proportioning valve 23. A motor CEU2 controls the electric motor 2, and a brake CEU26 controls hydraulic braking and regenerative braking. While a slip ratio (S) is low, the (Fr) is subjected to only regenerative braking with the valves closed. With an increase in (S), the by-pass valve 53 opens to increase braking force, thereby applying braking force efficiently and stopping a car at the shortest distance. |
