| 摘要 |
PROBLEM TO BE SOLVED: To set a servo ratio of a brake booster more freely than in conventional devices when a coil spring is compressed. SOLUTION: A first spring bearing seat 30 is provided on a valve plunger 11 to be extended radially outward, and a second spring bearing seat 31 is provided on a plate plunger 28 to be extended radially outward. Plural coil springs 32, 33 are elastically installed in parallel on both spring bearing seats 30, 31, and breake reaction is transmitted through the plate plunger 28, second spring bearing seat 31, coil spring 32, and first spring bearing seat 30 to the valve plunger 11. A synthesized spring constant of the coil springs 32, 33 disposed in parallel is a total of spring constants of the respective coil springs 32, 33, thereby the synthesized spring constant can be set large. |
