| 摘要 |
A master cylinder is provided to cut down the manufacturing cost of the master cylinder combined with the booster valve as well as the master cylinder combined with the dump valve by mechanically processing the hollow cast-iron product. A range of a body bore is restricted by a piston to define a master cylinder(24A) for pressing a brake port, and the piston is composed of a piston seal to separate a pressure port from a tank port, a first piston hole set(44) connecting a piston bore(42) and the pressure port to the piston bore by hydraulic pressure and a second piston hole set connecting the piston bore to the tank port by hydraulic pressure. A plunger is contained in the piston bore by sliding, and composed of a plunger hole set selectively connecting the first piston hole set to the plunger bore and a plunger seal unit selectively separating the first piston hole set from the plunger bore. The plunger bore is connected to the piston bore by hydraulic pressure, and the master cylinder is released to separate the first piston hole set from the plunger bore and the pressure port from the tank port. |
