| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pneumatic booster capable of securing the requisite braking force by raising quickly the servo force at the time of hard braking. <P>SOLUTION: A valve body 2 is coupled with a power piston partitioning inside a housing into a constant pressure chamber (negative pressure) and a variable pressure chamber, and a brake assisting mechanism 10 is interposed between a reaction disc 3 in the valve body 2 and a plunger 9. With movement of the plunger 9, a poppet seal 12 is opened to introduce the atmosphere into the variable pressure chamber, and a thrust force is generated at the power piston. At the time of hard braking, a plunger rod 23 advances toward a sleeve 21, and a ball 30 runs off to outside to cause the plunger rod 23 to abut to a reaction rod 22 directly. This causes the brake assisting mechanism 10 to shorten, and the moving amount of the plunger 9 can be made greater without receiving a reaction force from the reaction disc 3, and it is possible to raise the servo force quickly. <P>COPYRIGHT: (C)2007,JPO&INPIT |
