| 摘要 |
PURPOSE:To generate high pressure with a small device by decreasing the pressure on a push rod side, increasing the pressure on a valve case side with the movement of a spool via the depression of a brake pedal, and operating a master cylinder with this pressure difference. CONSTITUTION:When a brake pedal 6 is depressed to move a spool S against a reaction spring 4, the opening of the first throttle section a, is decreased, and the opening of the second throttle section a2 is increased. The pressure oil from a pump P flows into the other pressure chamber 2 via the third and second relay chambers 10, 11 to increase the pressure in the pressure chamber 2. The opening of the first throttle section a, is decreased, the pressure loss of the oil passing there is increased, and the pressure in one pressure chamber 1 is made near the tank pressure. A piston PS is moved in the arrow 7 direction by the pressure difference between both pressure chambers 1, 2, and a master cylinder is operated via a push rod 3. |
