Patent ID: 8881771

Claim:
A pressure damping device for a brake system that is provided in an oil passage of a hydraulic block so as to connect first and second hydraulic circuits for respectively controlling a liquid pressure transmitted to two vehicle wheels, the pressure damping device comprising: a cylindrical housing that is fixed to the oil passage, includes a first liquid pressure hole and a second liquid pressure hole respectively communicating with a main oil passage of the first and second hydraulic circuits, and is opened on one side thereof; a lid member that is coupled so as to close the opened one side of the housing; first and second pistons that are spaced apart from each other and move forward and backward within the housing; a spring that is interposed between the first and second pistons to provide an elastic force to the first and second pistons, wherein a sealing member is provided on an outer circumferential surface of each piston so that a space between the first and second pistons is sealed, and an air damping space whose volume is changed in accordance with a pressure of a liquid pressure is provided between the first and second pistons; and a damping member provided in the first and second pistons so as to be brought into contact with the lid member and the other side of the housing, respectively, and covering each of the first and second pistons.