| 摘要 |
PROBLEM TO BE SOLVED: To provide a negative pressure booster in which a coupling reception part for bearing a rear surface of a front shell half body is formed on a tie rod in an integrated manner, and a distance between the coupling reception part and an air tight connection part connected to a rear shell half body is regulated constant, the distance does not have to be adjusted therefore connection work of the front and rear shell half bodies by the tie rod, and attachment work of a master cylinder are facilitated, and in addition, coupling axial force between the coupling reception part and an attachment flange of the master cylinder is secured, and a through-hole of the front shell into which the tie rod is inserted is reliably sealed.SOLUTION: As a coupling reception part, a front flange 32 is formed on a tie rod 6 in an integrated manner. On at least one of facing surfaces of the front flange 32 and an attachment flange Ma1 of a master cylinder M, which face to a front shell half body 1a, an annular seal groove 38 for surrounding the tie rod 6 is formed. A seal member 39 contacting to the front shell half body 1a tightly is attached to the seal groove 38. |
