Browse Prior Art Database

HDD Shrink-on Disk Clamp with Increased Compliance and Low Radial Load

IP.com Disclosure Number: IPCOM000123971D
Original Publication Date: 1999-Sep-01
Included in the Prior Art Database: 2005-Apr-05
Document File: 1 page(s) / 58K

Publishing Venue

IBM

Related People

Moser, MA: AUTHOR [+3]

Abstract

Disclosed is a disk concept for a HDD (hard disk drive) which provides increased compliance and low radial load in a "shrink-on" design.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 59% of the total text.

HDD Shrink-on Disk Clamp with Increased Compliance and Low Radial Load

Disclosed is a disk concept for a HDD (hard disk drive)
which provides increased compliance and low radial load in a
"shrink-on" design.

   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.  On 3.5 inch drives recently shipped to IBM, a ring
which is heated and then shrink fitted on the hub has been used.  It
is a simple design which reduces the number of parts by eliminating
the need for screws.  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 axial compliance (minimum spring rate) without
exceeding a defined acceptable stress level.  This will provide a
consistent clamping load in spite of 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 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.  (see figure)
  1.  A cross sectional profile whi...