| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a reliable brake master cylinder allowing prevention of abutment of a projecting part of a spring retainer on a stopper part of a sleeve to prevent deformation and a break of the spring retainer and the sleeve when air bleeding work or operation of pressurization device in a brake system causes rapid retreat of a piston. SOLUTION: In this cylinder, the sleeve 23 is formed with an axially extending groove 23c. A distance between the rear end face 23c1 of the groove 23c and the radial projecting part 35 of the first spring retainer 35 in a non- braking state is set to a distance gotten by adding a prescribed additional distance to a retreating distance of the second piston 32 from a stationary position in the non-braking state to a position where a piston port 32a overlaps an opening 23a1 of a reservoir communication passage 23a.</p> |
