| 摘要 |
PURPOSE:To manually obtain a braking force according to a change in circumstances, by increasing pressure in a control chamber according to an operating force applied to an operational part. CONSTITUTION:When an operating force N is applied to an operational member 34 in the direction of an arrow Y, an input shaft 26 in a control chamber 14 is moved rearwardly, and a power piston 19 and a diaphragm 18 are also displaced rearwardly to close a vacuum valve 30. The displacement of the diaphragm 18 causes rearward movement of a plunger 29 to open an atmospheric valve 32. As a result, the atmosphere is induced through a communication hole 22 to an operational pressure chamber F, and simultaneously, the atmosphere is also induced to an operational pressure chamber D of a booster 1 to thereby operate a control piston 10. As a result, a braking force is generated. Then, the diaphragm 18 is forwardly displaced by the pressure differential between the operational pressure chamber F and a constant pressure chamber E in the control chamber 14 to thereby close the atmospheric valve 32 and be rendered in a neutral position. Under the condition, the braking force is determined in correspondence with the operating force N. |
