Braking hydraulic pressure control unit for motor vehicle

摘要

A braking hydraulic pressure control unit for a motor vehicle including a differential-acting piston having a plurality of pressure bearing portions facing an inlet compartment and an outlet compartment communicating with a master cylinder and rear wheel cylinders, respectively, of a vehicle braking system. The differential-acting piston is formed with shoe clearance compensating piston segments operative to reduce an inflow of a braking fluid into a spherical valve chamber at initial stages of brake application whereby unfavorable influences which would otherwise be exerted by the size of shoe clearances on a spherical valve at initial stages of brake application can be prevented.