Brake fluid pressure control apparatus

A brake fluid pressure control apparatus comprising:

• a flow control valve which has a casing, a spool and a spool spring biasing said spool, said casing having a master cylinder communicating port extending in a direction of movement of said spool and communicating with a master cylinder, a port communicating with a wheel cylinder, a port communicating with a variable-capacity reservoir through a normally-closed valve, and a first pump communicating port communicating with a discharge side of a pump that sucks the reservoir-side brake fluid and discharges it, said spool being slidable in said casing and defining passageways configured so that, when the spool is held in a stationary state by a biasing force of the spool spring when antiskid control is inoperative, said spool provides communication between said master cylinder communicating port and said wheel cylinder communicating port, and so that when said spool is moved and brought into a movable state against the biasing force of said spool spring by a pressure difference produced between two ends of said spool at least during a repressurizing process of antiskid control, said spool provides communication between said first pump communicating port and said wheel cylinder communicating port, and wherein said casing also has a second pump communicating port that communicates with the discharge side of said pump, and that also communicates with said wheel cylinder communicating port when said spool is in said movable state, said second pump communicating port facing towards said first pump communicating port and being disposed approximately perpendicularly to the direction of movement of said spool, said first and second pump communicating ports being connected to said master cylinder;
• a check valve provided between each of said first and second pump communicating ports and said master cylinder, said check valve being adapted to open when the master cylinder-side brake fluid pressure becomes a predetermined value higher than the pump discharge-side brake fluid pressure;
• and
• a cut-off valve provided between said master cylinder communicating port and said master cylinder, said cut-off valve being closed when said spool is brought into said movable state.