| 摘要 |
<p>PURPOSE:To feed oil in large amount under low pressure at the first stage, and in small amount under high pressure by providing a piston of large diameter to a master cylinder bore, and a piston of small diameter to a sleeve cylinder bore with a small diameter which is arranged on this bore. CONSTITUTION:When a lip 15a passes through a port 21 by left movements of the pistons 11, 8 with large and small diameters at the first stage of braking, liquid pressure in a chamber (A) rises, the oil in the chamber (A) flows through a path 35 in piston 8 into a pressure chamber B. The large amount of oil in the chamber B flows through a path 41 and a feeding port 42 of a sleeve cylinder 6 into a brake on one side. A small diametral piston 9 moves to the left under liquid pressure in the chamber B, and this moving rate is larger than that at the piston 8, because a spring 12 is weaker than a spring 13, so that liquid in a chamber C is fed in a large amount through a path 43 and a feeding port 44 to a brake on the other side. When a valve 29 opens under liquid pressure in the chamber B, oil flow from the chamber (A) is stopped because the chamber (A) conducts to a reservoir 4. The liquid pressure in the chambers B, C rises by only the pistons 8, 9, and high pressure oil is fed to each brake.</p> |
