Anti-lock brake system for vehicle

摘要

In an anti-lock system for a vehicle having a first valve arranged in a brake fluid pressure transmission line from a master cylinder to each brake device to operate under an anti-lock control signal, a second valve arranged to open for reducing the brake fluid pressure, a pressure fluid return device arranged to bring a brake pressure fluid into an accumulator for returning the pressure fluid to the upstream side of the first valve and a gate valve arranged in between the first valve and the master cylinder, the gate valve is provided with a balance piston which is arranged to receive at one end thereof the pressure fluid brought into the accumulator and to receive the pressure fluid of the brake device at the other end; and a shut-off valve device arranged at an axially intermediate part of the balance piston to close a passage between the master cylinder and the first valve according to the balance piston.