| 摘要 |
PROBLEM TO BE SOLVED: To more simplify an assembling operation of an actuation assist mechanism and a dimension management of the actuation assist mechanism while performing a plurality of pieces of actuation assist actuation upon emergency actuation.SOLUTION: Upon non-actuation, first and fourth parts 33a, 34a of position to be regulated of a vacuum valve seat member 29 are brought into contact with first and second straight line-shaped position regulating parts 31b, 31c to regulate the vacuum valve seat member 29 at the non-actuation position. Meanwhile, upon first emergency brake actuation, second and fifth parts 33b, 34b of position to be regulated are brought into contact with the first and second straight line-shaped position regulating parts 31b, 31c which are expanded and opened to regulate the vacuum valve seat member 29 at a first emergency brake actuation position. Further, upon second emergency brake actuation, third and sixth parts 33c, 34c of position to be regulated are brought into contact with the first and second straight line-shaped position regulating parts 31b, 31c which are further expanded and opened to regulate the vacuum valve seat member 29 at a second emergency brake actuation position. |
