Browse Prior Art Database

Expansion Absorbing Element to Prevent Warping of Actuator And Media Axes

IP.com Disclosure Number: IPCOM000101268D
Original Publication Date: 1990-Jul-01
Included in the Prior Art Database: 2005-Mar-16
Document File: 3 page(s) / 134K

Publishing Venue

IBM

Related People

Siverling, MM: AUTHOR

Abstract

Illustrated is a remedial appliance for thermally caused misalignment of an actuator axis or tower 10 (shown in Fig. 2) and a storage disk spindle or axis 12 in a computer file memory.

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Expansion Absorbing Element to Prevent Warping of Actuator And Media Axes

       Illustrated is a remedial appliance for thermally caused
misalignment of an actuator axis or tower 10 (shown in Fig. 2) and a
storage disk spindle or axis 12 in a computer file memory.

      Today's hard file memories generally have information stored on
a multiplicity of disk magnetic storage media which are stacked on a
common spindle.  Information stored on the media is accessed by
moving a multiplicity of magnetic transducers which are attached to a
common actuator assembly 32 (Fig. 2).  The transducers 34 move as a
unit to different radii of the disk storage media depending on which
concentric ring of media the information is to be stored based on the
address of the information.  For maximum efficiency it is desirable
to be able to read the information that was written at a particular
radius on all the media in the stack without having to reposition the
actuator containing the transducers.  This is only possible if the
axis about which the actuator rotates stays aligned to the axis of
rotation of the disk storage media in a rotary actuator machine.
There is a similar relationship required in a linear actuator machine
to be able to access the previously described information without
repositioning the actuator.

      Alignment of the actuator and media axes is controlled by the
disk enclosure base 14 (Fig. 2) to which they are fastened.  The base
has been shown to warp as a function of ambient temperature and also
as a function of thermal gradients caused by the warm up of specific
components as the file comes up to normal operating temperature.

      Described is a solution for warping which causes performance
problems in files, such as 5-1/4-inch file memories.  Without a
solution for warping, which causes misalignment of the axes 10 and
12, some files exhibit increased time to access information in the
stack of media. Some exhibit increased error rates due to
misalignment of information tracks and the magnetic transducers.
There are situations where information written at one file
temperature condition could be irretrievable at another temperature...