| 摘要 |
PROBLEM TO BE SOLVED: To enlarge the boosting ratio of a motor-driven disc brake and reduce the drag of brake pads. SOLUTION: A caliper body 3 is equipped with a first and a second ball ramp mechanisms 11, 12, a motor 10, and a pad wear compensating mechanism 13. The rotation of the rotor 19 of the motor 10 is converted into linear motions by the first and second mechanism 11, 12 so that the drag is reduced by pressing and separating brake pads 5 and 6 uniformly to a disc rotor 2 through a piston 25 and a claw 4. Thread grooves 22, 23, 28, 29 in the first and second mechanism 11, 12 are made under one pitch so that the lead with respect to the rotational displacement is made small sufficiently, which allows enlargement of the boosting ratio. Using the pad wear compensating mechanism 13, only the rotational displacement of the rotor 19 exceeding the specified extent is transmitted to the piston 25, which is advanced by an adjusting screw part 36 to compensate the wears of the brake pads 5 and 6. |
