| 摘要 |
PURPOSE:To obtain a spindle motor capable of securing a sufficient binding strength even though its shape gets smaller and thinner by binding a hub supported by a stationary member in a freely rotatable manner to a rotor by welding to which a rotor magnet is to be attached. CONSTITUTION:In the case of a fixed shaft type motor, a stationary member 20 has a bracket 22 and a center shaft portion 23; and the center shaft portion 23 has a ring-shaped base portion 23a, a cylindrical shaft portion 23b, a ring- shaped wall portion 23c attached to the perimeter, and a ring-shaped flange 23d attached to lower end perimeter, and the base portion 23a is fitted and fixed to the inside of a circular hole 22b of the bracket 22. On the other hand, a rotating member 21 has a hub 27 and a rotary yoke 30, and the hub 27 has a ring-shaped base portion 27a, a hollow cylinder 27b formed in one united body with the both the ends projected to up-and-down direction on the inner surface, and a ring-shaped external wall portion 27c projected out to the perimeter. And the hub 27 and a rotor yoke 28 is fixed by projection welding. As a result, a large binding strength can be obtained so that a compact and thin type motor can be designed. |
