Disclosed herein is a disc brake to allow a shim to be easily coupled to a pad plate and to maintain strong coupling between the shim and the pad plate so as to prevent separation of the mounted shim. The disc brake includes pad plates each having frictional pads, a piston and a caliper housing to press the pad plates toward a disc, a shim attached to one surface of each of the pad plates to be pressed by the piston or the caliper housing, a coupling hook protruding from the shim and having a coupling protrusion at an end thereof, and a coupling hole perforated in each of the pad plates to allow the coupling hook to be inserted and coupled into the coupling hole.
1. A disc brake comprising: pad plates each having frictional pads; a piston and a caliper housing to press the pad plates toward a disc; and a shim attached to one surface of each of the pad plates to be pressed by the piston or the caliper housing, the disc brake further comprising:
a coupling hook protruding from the shim and having a coupling protrusion at an end thereof; and
a coupling hole perforated in each of the pad plates to allow the coupling hook to be inserted and coupled into the coupling hole,
wherein the coupling hole is perforated in a central portion of the pad plate through both surfaces of the pad plate,
wherein the frictional pads of each of the pad plates include a first frictional pad and a second frictional pad separately coupled to the other surface of the pad plate at opposite sides of the coupling hole so as to be separated from each other,
wherein the coupling hook is press-fit into the coupling hole to prevent separation of the shim from the pad plate,
wherein the coupling hook and the coupling hole are elongated in a radial direction of the disc, and
wherein the coupling hook is integrally formed with the shim.
2. The disc brake according to claim 1 , wherein:
the coupling hook and the coupling hole are elongated in a longitudinal direction of a recess defined between the first frictional pad and the second frictional pad; and
the coupling protrusion of the coupling hook is larger than the coupling hole and is smaller than a distance between the first frictional pad and the second frictional pad.
3. The disc brake according to claim 1 , wherein the shim is thinner than the pad plate.
4. The disc brake according to claim 1 , wherein the coupling protrusion is elongated in a radial direction of the disc.
5. The disc brake according to claim 1 , wherein the coupling hook is integrally formed with the shim via injection molding.
6. The disc brake according to claim 5 , wherein the shim is made of resin.
7. The disc brake according to claim 1 , wherein the coupling hook is integrally formed with the shim via welding or soldering.
8. The disc brake according to claim 7 , wherein the shim is made of metal.