| 摘要 |
<p>PROBLEM TO BE SOLVED: To stabilize a friction coefficient to a piston without causing a cost increase to improve the sealing function or the like of a seal member by coating at least the inner peripheral surface, brought into close contact with the outer peripheral surface of the piston, of a piston seal member for a disc brake, with an anti-fiction composition. SOLUTION: When brake fluid pressure is supplied to both hydraulic chambers 8, 8 of a caliper 6, each piston 4 is actuated to advance, and friction pads 3 are brought into pressure contact with both side faces of a brake disc 2 to brake the rotation of wheels. In this case, the inner peripheral surface of a dust seal member 12 mounted in a first annular groove 10 of the caliper 6 to prevent the infiltration of dust and rainwater into the hydraulic chamber 8, and the inner peripheral surface of a brake clearance-adjusting seal member 13 deformed in rolling by friction consequent to the advance of the piston 4 when pressing the hydraulic chamber 8, are respectively coated with anti-friction agent 14. The stability of friction coefficients of the seal members 12, 13 can thereby be maintained satisfactorily regardless of the hardness and interference change of the seal members 12, 13 due to the change of temperature.</p> |
