Patent attributes
A mechanical pressurization device is connected to a common passage, and brake cylinders provided respectively for front left and right and rear left and right wheels are connected to the common passage respectively via pressure holding valves. Each of the pressure holding valves in the front is a normally open valve, and each of the pressure holding valves in the rear is a normally closed valve. In the event of an abnormality in which a hydraulic pressure in the common passage cannot be controlled using a hydraulic pressure produced by a power hydraulic pressure source, a hydraulic pressure in the mechanical pressurization device is supplied to the front brake cylinders provided respectively for the front left and right wheels.