| 摘要 |
PURPOSE:To prevent the efficiency of braking from falling, by reducing the rate of the decrease in braking oil pressure when it is judged that a vehicle is moving on a bad road, so as to prevent the increase in the distance of braking during the movement on the bad road. CONSTITUTION:Oil passages 5, 6 from an oil pressure control circuit 3 are connected to the braking oil chambers 4 of wheel brakes Bl, Br. When braking oil pressure is applied to the braking oil chambers 4, pistons 7, 8 are driven away from each other to bring brake shoes 9, 10 into contact with brake to apply braking torque thereto. If the braking oil pressure in each braking oil chamber 4 is too high, the braking torque applied to the brake drum by the brake shoes 9, 10 becomes so large that the wheel is locked. At that time, the oil pressure control circuit 3 reduces the braking oil pressure so as to unlock the wheel. |
