Patent ID: 8281905

Claim:
A caliper disc brake, comprising: a caliper housing having a cylinder; a piston for moving forward and backward within the cylinder of the caliper housing; a dust seal mounted at a front end of an opening of the piston; a first sealing member disposed between an inner surface of the cylinder and an outer surface of the piston at the rear of the dust seal; and a second sealing member separated from the first sealing member by a designated interval and disposed between the inner surface of the cylinder and the outer surface of the piston, wherein a plurality of oil channels, to communicate a first space around an outer circumferential surface of the piston, formed by the first sealing member and the second sealing member, and a second space around a rear surface of the piston, formed by the second sealing member and the cylinder, with each other to operate a rollback function of the second sealing member, are formed in the piston, and each of the plurality of oil channels includes a first through hole extended from the outer circumferential surface of the piston toward the center of the piston, and a second through hole bent from the first through hole and extended to the rear surface of the piston in the lengthwise direction of the piston.