| 摘要 |
PURPOSE:To substantially prevent a brake squeak since a natural frequency, even when conformed to a noise vibration generated by a disk and a pad, is displaced from a human audible range, when the natural frequency of a piston is set to out of a specific range. CONSTITUTION:In a piston 17a, its internal diameter and depth from an opening end face 19a to the bottom part are formed smaller than in the past, to form the piston 17a in large thickness as a whole. In this way, a natural frequency of the piston can be set so as to be out of a range from 20Hz to 20kHz, and the natural frequency can be displaced from an audible frequency region. Consequently, even in the case of generating a squeak vibration in an audible frequency range in a pad 4, the piston 17a can be prevented from its resonance with this squeak vibration. Accordingly, even without providing a shim and a thin plate, a brake squeak, generated by conforming the natural frequency of the piston 17a to the squeak vibration generated between a disk 3 and the pad 4, can be substantially prevented. Thus by decreasing the number of part items, a cost can be reduced. |
