Browse Prior Art Database

Direct Access Storage Device Recording Head Parking Procedure

IP.com Disclosure Number: IPCOM000117798D
Original Publication Date: 1996-Jun-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 48K

Publishing Venue

IBM

Related People

Ting, B: AUTHOR [+2]

Abstract

Disclosed is a Direct Access Storage Device (DASD) start-stop procedure for low flying head on dual-textured disk.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 63% of the total text.

Direct Access Storage Device Recording Head Parking Procedure

      Disclosed is a Direct Access Storage Device (DASD) start-stop
procedure for low flying head on dual-textured disk.

      As the capacity of DASD devices increases, there is a continual
push for higher magnetic recording density and smaller head-disk
spacing.  To accomplish these without reducing the reliability of the
drive, it is necessary to make the disk surface smooth to produce
magnetic uniformity and minimize the chance of head-to-disk contact
during operation.  A consequence of this smooth surface is an
increase in the head-to-disk stiction when head is parked on the
disk.  To avoid this high stiction, a region on the disk surface is
intentionally textured to a desired roughness and is designated for
head parking.

      As the fly height continues to drop as high recording density
demands, a point is reached where the head is not being able to
take-off, or fly, in this textured zone because of the rough texture
features.  The head continues sliding on the disk surface, which
causes the disk to wear.

      The invention uses a unique sequence during file start-up and
shut-down periods to resolve the aforementioned problems.

The unique start/stop (s/s) sequence in this invention consists of
moving the heads in two steps:
  1.  Start-up:  as the file is being powered up, as soon as the
drive
       motor starts to spin, the actuator pushes the heads to an area
      ...