Patent ID: 8684029

Claim:
A check valve of a hydraulic brake system, the check valve comprising a valve housing press-fitted into an inner stepped portion of a perforated hydraulic block, the valve housing defining an inner oil passage, a ball accommodated in the valve housing to open or close the inner oil passage, a spring to elastically support the ball, and a valve seat coupled to the valve housing to guide the spring, wherein the valve housing includes a tapered front end having a smaller diameter than a cylindrical middle end, the middle end extending from the front end by a predetermined length to allow the ball and spring to be accommodated within the middle end, a rear end stepped from the middle end to have a greater diameter than the middle end, and a flange circumferentially bent from the rear end to have a greater diameter than the rear end, and wherein the valve seat has an outer diameter equal to an inner diameter of the rear end so as to be press-fitted into the rear end of the valve housing, the valve seat including an oil hole penetrating the interior thereof.