Clamping of Magnetic Disk Stack with a Top Ring
Original Publication Date: 1982-Aug-01
Included in the Prior Art Database: 2005-Feb-09
This article describes a method to reduce disk distortion in a Head Disk Assembly (HDA). The magnetic disks must be held rigidly to prevent radial migration due to thermal shock, start/stop acceleration impulses, and centrifugal force which would cause data track and servo track runout, thereby degrading the file's read/write performance. The disk stack is held in place by a bell-shaped clamp which contacts the upper most disk directly, causing severe distortions predominantly in the top disk. The distortions have been isolated to the disk inside diameter, near the bell clamp interface, and occurred when the six bolts clamping the disk pack together were torqued to generate 10,000 pounds of compressive force.