| 摘要 |
PURPOSE:To prevent scuffing of a rotor by holding a diameter of the rotor to a fixed value, that is, by forming a ring-shaped stopping protrusion in one side end face of the rotor so as to engage the peripheral surface of this stopping protrusion with the engagement groove of a rotor cover further adapt the internal peripheral surface of said stopping protrusion to a holding disc. CONSTITUTION:A ring-shaped stopping protrusion 3x is integrally formed with one side end face 3a of a rotor 3, and a holding disc 4 of stepped cylindrical shape is interposed between the one side end face 3a of the rotor and a rotor cover 6. While the peripheral surface of this stopping protrusion 3x is engaged with an engagement groove 6a formed in a rotor side face of the rotor cover 6. Further the periphery of a large contour part 4a of the holding disc 4 is forced to be attached to the internal peripheral surface of the stopping protrusion 3x, while a small contour part 4b of the holding disc 4 is forced to be attached to the internal peripheral surface of the rotor cover 6.
|
