| 摘要 |
PURPOSE:To obtain the control pressure of good responsiveness and stability by feeding a pressurized fluid to the primary pressure chamber of a booster for a brake mechanism and concurrently controlling a servo motor. CONSTITUTION:In an initial operation stage, a plunger 24 is quickly actuated on a fluid pressure working on a primary piston 65 due to solenoid valves 73 and 74. Thereafter, the control of the plunger 24 is transferred to a servo motor 68. On the other hand, pressure in a control pressure chamber 6 is introduced into a secondary pressure chamber 53 through a control passage 34, thereby actuating the plunger 24 upward against a pressing force by an elastic body 59. And when the plunger 24 has been moved upward, pressurized fluid in the control passage is discharged from a discharge passage 40. As a result, pressure within the control pressure chamber 6 is regulated to the pressing force of the elastic body 59 corresponding to the fall amount of the primary piston 65 as caused by the servo motor 68, or a level corresponding to an input caused on an input shaft 8. |
