| 摘要 |
PROBLEM TO BE SOLVED: To provide a booster restricting deformation of a rear shell in small when input force is applied on an input shaft. SOLUTION: In a booster 1 provided with a master bag 4 comprised of a front shell 2 and a rear shell 3, a plate member 6 parting an inside of the master bag 4 to a constant pressure chamber 7 and a variable pressure chamber 8, a valve body 13 supported by the plate member 6 and having a valve mechanism opening and closing the variable pressure chamber 8 built in, an input shaft 12 inserted through the rear shell 3 and operate the valve mechanism built in the valve body 13, and an output shaft 17 inserted through the front shell 12 and connected to the valve body 13, the rear shell 3 is provided with plural beads expanding radially toward outside from a circumference edge of a mounting seat surface part 9 projecting in an outside center part of the rear shell 3. |
