Browse Prior Art Database

Hard Disk Drive Disk Clamp with High Compliance and Low Radial Load

IP.com Disclosure Number: IPCOM000106165D
Original Publication Date: 1993-Oct-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 2 page(s) / 91K

Publishing Venue

IBM

Related People

Scheffel, JN: AUTHOR

Abstract

Disclosed is disk clamp concept for a HDD (hard disk drive) which provides high compliance and low radial load within a limited amount of space.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 56% of the total text.

Hard Disk Drive Disk Clamp with High Compliance and Low Radial Load

      Disclosed is disk clamp concept for a HDD (hard disk drive)
which provides high compliance and low radial load within a limited
amount of space.

      A disk clamp is a device used to secure the disk stack in a
HDD.
  It is typically a disk or ring with one or more holes, which is
placed on the top to the disk stack and secured by one or more screws
or nuts.
  It is a simple device which has been made in a variety of different
shapes and forms; however, there are subtleties in the design which
can make optimization a challenging problem.

      There are two primary design goals for a disk clamp.  One is to
provide maximum compliance (minimum spring rate) without exceeding a
defined acceptable stress level.  This will provide a consistent
clamping load despite tolerances and dimensional changes caused by
thermal expansion or contraction.  The second goal is to transmit
only axial clamping force into the stack, with no radial force.  This
eliminates undesirable distortion of the first disk under the clamp
which can be a source of problems in reading and writing the data
tracks.

      The invention disclosed here is a new disk clamp concept which
was conceived in an effort to achieve these two goals by the
following unique features (Fig. 1).

1.  A profile which is tapered (thinner at the inner diameter than at
    the outer diameter), creating a uniform stress distribution ov...