| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the dragging resistance of a friction pad by forming a cylinder so that the inside diameter on the deep side from a ring mounting groove is larger than the opening end side thereof, floating a piston by a boot and a seal ring, and performing an easy plating. SOLUTION: When the hydraulic pressure acting on a cylinder 33 pressing a piston 31 is raised, a seal ring 39 is pressed to the wall of a rotor-side ring mounting groove 41 by the sliding resistance with the piston 31 and the hydraulic pressure acting on the ring mounting groove 41. At this time, the piston 31 is floated and held by the seal ring 39 and a boot 35. Thus, even if a rotor or caliper 12 is deformed to tilt a friction pad 22A, the piston 31 tilts within the cylinder 33 and follows the friction pad. According to this, the contact surface of the friction pad 22A uniformly makes contact with the rotor. Thus, the dragging resistance of the friction pad 22A can be reduced.</p> |
