| 摘要 |
PROBLEM TO BE SOLVED: To secure a large output surely even in case of a powerless woman driver in the case where such large braking force as in an emergency brake is required. SOLUTION: An annular belleville spring 41 is made to contact with an end 36b at the rear side of an output shaft 36 from this rear side. In a state that a brake servo unit is nonoperative, a clearance is kept up in space between a reaction disk 35 and an end face 17a of a valve plunger 17, and likewise another clearance δ is kept up in space between the belleville spring 41 and a stepped end face 6B. When leg power (input) of a brake pedal comes the specified value after a brake booster is operated, the belleville spring 41 and the stepped end face 6B both come into contact with each other, and afterward, the belleville spring 41 is compressed up to the limit. From this point of time, output reaction force is all transmitted to a valve body 6 but become untransmitted to the valve plunger 17. With this constitution, this brake booster is turned to a full-load point quickly. |
