An objective of the present invention is to provide a piston of a caliper brake, increasing a contact area between the piston and a pad to enhance braking performance, minimizing deformation of the piston to enhance durability, and reducing the weight of the piston to enhance vehicle′s mileage; and a caliper brake having the same and an injection mold to manufacture the same. To this end, in the piston for a caliper brake pressing a pad towards a disk according to movement by hydraulic pressure of brake oil to move the brake pads onto the disk, the front end surface placed on an inlet side of the brake caliper is formed in a closed shape, a hollow part opened to the rear side is formed inside, and the rear end surface in contact with the pad upon application of the hydraulic press is formed along the circumference of the rear end part of the hollow part. The inner surface, having the hollow part formed thereon includes: a large diameter cylindrical part; an undercutting part whose diameter is gradually reduced towards the rear side of the large diameter part; and a small diameter cylindrical part connected to the rear side of the undercutting part.
展开▼
