| 摘要 |
An engaging projection (19) formed on a rear surface of a pressure plate (2a) is inserted into an engagement hole (26) formed on an outer shim plate (4a). Then, a flat surface section (20a, 20b) forming a side of the engaging projection (19) is opposed to a straight section (27a, 27b) forming the inner circumferential periphery of the engagement hole (26). Furthermore, with the outer shim plate (4a) disposed at a neutral position relative to the pressure plate (2a), the flat surface section (20a, 20b) and the straight section (27a, 27b) are slightly tilted. This causes the rotation of the outer shim plate (4a) around the center axis (O) of a piston (14a) based on the rotational force acting from the top surface of the piston (14a) on the outer shim plate (4a) to be restricted by the flat surface section (20a, 20b) and the straight section (27a, 27b) being brought into linear contact with each other. |
