Hydraulic pressure control unit for vehicle brake system and vehicle brake system

A hydraulic pressure control unit for a vehicle brake system,

• the brake system including:
• a hydraulic circuit having:
• a primary channel that communicates between a master cylinder and a wheel cylinder;
• a secondary channel to which brake fluid in the primary channel is released;
• and a supply channel through which the brake fluid is supplied to a first intermediate portion as an intermediate portion of the secondary channel,
• a first downstream end as a downstream end of the secondary channel being connected to a second intermediate portion as an intermediate portion of the primary channel, and
• a first upstream end as an upstream end of the supply channel communicating with the master cylinder,
• the hydraulic pressure control unit comprising:
• an inlet valve provided in a region on a wheel cylinder side in the primary channel with the second intermediate portion being a reference;
• an outlet valve provided in a region between a second upstream end and the first intermediate portion in the secondary channel, the second upstream end being an upstream end of said secondary channel;
• a first switching valve provided on a master cylinder side in the primary channel with the second intermediate portion being a reference;
• a second switching valve provided in the supply channel;
• a pump provided in a region between the first intermediate portion and the first downstream end in the secondary channel, a suction side thereof communicating with said first intermediate portion, and a discharge side thereof communicating with said first downstream end;
• an internal channel being a part of the secondary channel and providing a channel between the first intermediate portion and the outlet valve;
• and
• an accumulator provided in the internal channel, wherein
• the internal channel is configured to allow a flow of the brake fluid that flows into the accumulator from the first intermediate portion.