Recording disk having improved centering hub and magnetic yoke arrangement

Abstract

Recording disk, such as a data recording disk, having: 1. annular main body having datum surface intended to rest on disk drive turntable; 2. hub having a center hole; 3. magnetic yoke, generally concentric with the main body and hub; said recording disk being characterized by: A. yoke plate adherend on one side of main body, being radially closer to the center hole than datum surface and adjacent the hub; B. axial spacing between yoke plate and hub; and C. axial spacing between datum surface and the side of the yoke plate away from the yoke plate adherend. Design (keeping disk datum and yoke plate adherend on main body rather than on hub) maintains elasticity of the hub (not restricting it like designs in which yoke plate is glued to hub) giving good disk centering onto disk drive spindle. Preferably, hub is made of material having higher elasticity than main body, and both are integral, i.e., injection molded in intimate contact. Stretched surface recording (SSR) disks can be made with this hub design.

Dependencies are inferred from the claim text.