Patent ID: 8348354

Claim:
A vehicle braking system comprising: an input piston moveably supported within a cylinder along an axial direction; an operation portion connected to the input piston; a pressure piston provided coaxially with the input piston, moveably supported within the cylinder along its axial direction, which is allowed to be depressed by the input piston; a control hydraulic pressure setting unit that sets a control hydraulic pressure according to an operation amount inputted from the operation portion to the input piston; an electromagnetic hydraulic pressure supply unit that regulates a hydraulic pressure supplied from a hydraulic pressure supply source to the control hydraulic pressure so as to be applied to the input piston and the pressure piston such that a braking hydraulic pressure is generated; a mechanical hydraulic pressure supply unit that regulates the hydraulic pressure supplied from the hydraulic pressure supply source to the control hydraulic pressure according to the operation amount transmitted from the operation portion to the pressure piston through the input piston so as to be applied to the pressure piston such that the braking hydraulic pressure is generated; and an operation force absorbing unit that absorbs an operation force input from the operation portion to the input piston, wherein the electromagnetic hydraulic pressure supply unit is capable of supplying the control hydraulic pressure to one of a first pressure chamber and a second pressure chamber in a moving direction of the input piston, and the operation force absorbing unit includes a communication passage formed in the input piston, through which a compression fluid is supplied and released between the first pressure chamber and the second pressure chamber.