Browse Prior Art Database

Slider Feature Changes to Increase Shock Resistance

IP.com Disclosure Number: IPCOM000111136D
Original Publication Date: 1994-Feb-01
Included in the Prior Art Database: 2005-Mar-26
Document File: 2 page(s) / 93K

Publishing Venue

IBM

Related People

Brooks, WW: AUTHOR [+4]

Abstract

As files get smaller, damage from shock loading is becoming a major concern. Some slider modifications to help protect against shock damage are disclosed.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Slider Feature Changes to Increase Shock Resistance

      As files get smaller, damage from shock loading is becoming a
major concern.  Some slider modifications to help protect against
shock damage are disclosed.

      Damage to the disks in a hard file during a shock event has
been determined by a number of researchers to be due to the impact of
the heads back onto the disks, rather than due to damage done when
the heads and disks are in contact or when the heads leave the disks.

      When a Head-Suspension Assembly (HSA) has been driven off of
the disk because of high acceleration, the slider is able to freely
vibrate about the load dimple, and will tend toward the Static

Attitude (SA) which the HSA had before file build.  This means that
the slider Air Bearing Surface (ABS) will almost certainly not be
parallel to the disk when it impacts the disk on it's return.
Because the ABS is not parallel to the disk at impact, one or the
other of the slider body corners or the ABS corners will make first
contact with the disk.  This 'corner' feature will act like a
miniature hardness tester in plastically deforming the disk, given a
sufficiently large impact velocity of the head back into the disk.

      The maximum amount of available energy to cause plastic
deformation of the disk is the total mechanical energy of the HSA
relative to the disk.  We can decrease the percentage of the total
energy which will be absorbed through plastic deformation of the disk
by increasing the contact area between the slider and the disk.  This
may be done by making changes in the following three areas.

      The corners of the slider body are obvious sources of sharp
disk indenters, so they must be recessed far enough back from the ABS
so that they cannot touch the disk during impact, no matter what the
static attitude is.  To work, the slider body will need to be
recessed back beyond the cone defined by the largest of the pitch and
roll static attitude, with the center of the cone being on the ABS
di...