| 摘要 |
An apparatus includes a mounting ring (102) and a collar (118). The mounting ring (102) includes an upper ring portion (102a) and a lower ring portion (102b) secured to the upper ring portion (102a). Each of the upper ring portion (102a) and the lower ring portion (102b) has an inner ring surface (112) defined by a plurality of radii (Rm, Rs, Rl). The collar (118) is disposed in the mounting ring (118) and includes a substantially cylindrical outer collar surface (120). The substantially cylindrical outer collar surface (120) is disposed proximate the inner ring surface (112). |
