| 摘要 |
<p>PROBLEM TO BE SOLVED: To increase a brake effective diameter by providing a piston with an intermediate member, having a press protrusion surface, which has a portion positioned eccentrically in the outer peripheral direction of a disc rotor by a radial distance, larger than the radius distance between the rotation center of a disc rotor and the center of a piston, and the portion forms the press center of a pad. SOLUTION: Though the center 01 of a piston 3 to press a pad 4 is unchangeable, an intermediate member 7 has a press protrusion surface 7a having a portion 02 which is the press center of the pad 4 and positioned eccentrically in the outer peripheral direction of a disc rotor 8 by a radius distance R2 higher than a radius distance R1 between the rotation center of a disc rotor 8 and the center of a piston 3, the press protrusion surface pressing the pad 4 through a back plate 5. Thus, the press force of the pad 4 exerted on the disc rotor 8 is applied on a portion having a radius distance R2 higher than a radius distance R1 between the rotation center of the disc rotor 8 and the center 01 of the piston 3. A brake effective diameter is increased without varying the position of the piston 3 based on the disc rotor 8 and a brake effect is improved.</p> |
