PURPOSE: To realize both of pressure intensification of electric control pressure and fail-safe against abnormality of the electric control pressure by providing a pressure intensification control mechanism between a master cylinder, an electric fluid pressure control device and a wheel cylinder in a braking device having both of the master cylinder and the electric fluid pressure control device as a fluid pressure control device.
CONSTITUTION: A pressure intensification control mechanism 60 has cocentrically fixed first and second pistons 64, 66 as a pressure intensifying piston 70, and the second piston 66 forms a valve system jointly with first and second seal members 90, 94. The valve system can intensify pressure by the pressure intensifying piston 70 by way of closing a fluid pressure control valve 22 in the state where the fluid pressure control valve 22 as an electric fluid pressure control device is normal and realizes fail-sate by communicating a master cylinder 12 to a wheel cylinder 38 by way of opening it in the state where the fluid pressure control valve 22 is abnormal.
OTA MASASHI
NAKAMURA AKIRA
