To enlarge the range of applicable loads while realizing miniaturization and applying energization in the direction of pad expansion.

A coil portion 30C in a rattle spring 30 is disposed between a stopper 30A for a caliper 18 and a pusher section 30B. A pad pin 20 is passed through the coil portion 30C. A contact 46 forming the pusher portion 30B is made to energize both pads 14 and 16 while the stopper 30A is inserted in the stopper hole 32 to fix it to the caliper 18. In this manner an energizing force is provided by the coil portion 30C so that the spring may be miniaturized and able to set wider range of loads. By making the rattle spring 30 out of one single spring wire, the cost of manufacturing may be decreased. As the contact 46 is contacted obliquely with a back plate 26 the spring applies energizing action to both pads 14 and 16 not only in the direction of the radius of a rotor 12 but also in the direction of expansion of the pads 14 and 16.