Abstract: This disc brake includes an attachment member having a pad guide part, a pair of friction pads, a caliper, and a pad spring. The pad guide part includes a recessed part, which is recessed in a disc rotation direction with respect to a bottom surface in a region on a disc radial direction outer side, in a region of a bottom part of the pad guide part on a disc radial direction inner side. The pad spring includes a guide part provided to be able to come into contact with a wall surface and the bottom surface of the pad guide part on the disc radial direction outer side and configured to guide movement of a protruding part in a disc axial direction, and a fitting part protruding in the disc rotation direction from the guide part and configured to elastically fit into the recessed part.

Abstract: Provided are a disc brake and a piston whose weights can be effectively reduced. A disc brake includes a piston configured to press a pad against a disc. The piston includes a body member formed into a bottomed cylindrical shape and including a cylinder portion and a bottom portion. The cylinder portion and the bottom portion are approximately equal in wall thickness. The piston further includes a plate-shaped member fixed to an external bottom surface of the body member and disposed within a range of the external bottom surface and in a region including a center of the external bottom surface.

Abstract: Provided are a disc brake and a piston whose weights can be effectively reduced. A disc brake includes a piston configured to press a pad against a disc. The piston includes a body member formed into a bottomed cylindrical shape and including a cylinder portion and a bottom portion. The cylinder portion and the bottom portion are approximately equal in wall thickness. The piston further includes a plate-shaped member fixed to an external bottom surface of the body member and disposed within a range of the external bottom surface and in a region including a center of the external bottom surface.