Hydraulic unit for vehicle brake apparatus

摘要

A hydraulic unit for a vehicle brake apparatus having a master cylinder and a wheel cylinder includes a housing formed with a pipe line connecting between the master cylinder and the wheel cylinder, a pump disposed in the housing for sucking and discharging a brake fluid to boost pressure of the brake fluid, and a reservoir piston disposed in a hole formed in the housing so as to be movable slidably back and forth, the reservoir piston partitioning a reservoir chamber within the hole for temporarily storing the brake fluid discharged from the wheel cylinder. The hydraulic unit further includes a cover disposed in the hole to close one end on an atmospheric side of the hole, the cover being formed with a fluid reservoir chamber for storing the brake fluid leaking from the pump.

主权项

1. A hydraulic unit for a vehicle brake apparatus having a master cylinder and a wheel cylinder comprising:
a housing formed with a pipe line connecting between the master cylinder and the wheel cylinder to allow a brake fluid to pass therethrough; a pump disposed in the housing for sucking and discharging the brake fluid to boost pressure of the brake fluid; a reservoir piston disposed in a hole formed in the housing so as to be movable slidably back and forth, the reservoir piston partitioning a reservoir chamber within the hole for temporarily storing the brake fluid discharged from the wheel cylinder; a cover disposed in the hole to close one end on an atmospheric side of the hole, the cover being formed with a fluid reservoir chamber for storing the brake fluid leaking from the pump, and the cover having a substantially cylindrical shape so that the fluid reservoir chamber is formed in the hole when the cover is inserted in the hole; and a drain passage formed in the housing for leading the brake fluid leaking from the pump into the fluid reservoir chamber.