| 摘要 |
PURPOSE:To obtain a smooth step force application state by obtaining the toggle braking that is proportional to the step force applied to a brake pedal up to the full braking as soon as the step force is applied to the brake pedal. CONSTITUTION:If a driver applies step force to a brake pedal when the driver requires braking, a spool piston 25 advances in the control piston 19 of a power piston 3. In addition, the port of the spool piston 25 shot off a return circuit and the jumping pressure in a boost chamber 10 is increased and then jumping operation is performed. Then the power piston 3 advances and immediately the pressurization chamber 13 of the power piston connects the control piston 19 to the other port 26 of the spool piston 25. As a result, the boost pressure coming from a boost hydraulic circuit 34 is introduced to the boost chamber 10. |
