| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a required brake force by promptly starting up a servo force in abrupt braking in a pneumatic booster. <P>SOLUTION: A valve body 2 is connected with a power piston which partitions a constant pressure chamber (negative pressure) and a transformation chamber inside a housing. A brake assist mechanism 10 is intervened between a reaction disc 3 inside the valve body 2 and a plunger 9. A poppet seal 12 is opened by the movement of the plunger 9, air is introduced into the transformation chamber, and thrust is generated in a power piston. A plunger rod 23 is made to advance to a sleeve 21 in the abrupt braking, and a ball 30 escapes to an outer side and the plunger rod 23 is brought into direct contact with a reaction rod 22. Therefore, the brake assist mechanism 10 can be shortened, and the movement amount of the plunger 9 can be made larger without receiving a reaction force from a reaction disc 3, thus promptly starting up the servo force. <P>COPYRIGHT: (C)2004,JPO |
