| 摘要 |
PURPOSE: To improve the responsiveness of a booster by positioning a breather valve, constituted of a second valve seat and the seat part of a valve component, on the outside of a vacuum valve constituted of a first valve seat and the seat part of the valve component, and leading the air, having passed the breather valve, rapidly into a transforming chamber. CONSTITUTION: Valve mechanism 5 is constituted of a first annular valve seat 21 formed at the inner peripheral part of a valve body 2, a second annular valve seat 22 provided at a valve plunger 12 and disposed outward side of the first valve seat 21, an annular valve component 23 disposed on the rear side of both valve seats 21, 22 so as to be brought into contact with and separated from both valve seats 21, 22, and a spring 24 for placing an input shaft 13 and the valve plunger, provided with the second valve seat 22, into non-operating positions. A vacuum valve 25 is constituted of the first valve seat 21 and the inward side annular seat part of the valve component 23 brought into contact with and separated from the first valve seat 21, and a breather valve 26 is constituted of the second valve seat 22 and the outward side annular seat part of the valve component 23 brought into contact with and separated from the second valve seat 22. The air having passed the breather valve 26 is rapidly led into a transforming chamber B. |
