Browse Prior Art Database

Method and Apparatus for Reading and Storing Data in Channels on a Hard Disk Drive

IP.com Disclosure Number: IPCOM000015017D
Original Publication Date: 2001-Aug-01
Included in the Prior Art Database: 2003-Jun-20
Document File: 3 page(s) / 51K

Publishing Venue

IBM

Abstract

Disclosed is a method for increasing the volume of the bit cell in a synthetic spin filter or spin valve magnetic medium of a hard disk drive. The method records and reads data perpendicular from the drive surface, positioning multiple fixed GMR heads in channels in the drive surface.

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  Method and Apparatus for Reading and Storing Data in Channels on a Hard Disk Drive

   Disclosed is a method for increasing the volume of the bit cell in a synthetic spin filter or spin valve magnetic medium of a hard disk drive. The method records and reads data perpendicular from the drive surface, positioning multiple fixed GMR heads in channels in the drive surface.

   Current hard disk drives use a movable drive head assembly that reads and writes data at the horizontal surface of the drive medium. As current bit cell sizes decrease with increasing density, there is a risk of the bit cell's becoming thermally unstable and thus causing degradation of data. Thus, there is a real limit to density of bit cells in a horizontal surface.

     The proposed method carves parallel channels in the surface of the medium, and places a head-drive assembly in each channel. Each drive assembly houses multiple GMR drive heads to read each side of the channel and the bottom of the channel. Figure 1 shows the arrangement schematically.

FIGURE 1.

     Because the channels are concentric circles, the drive head assemblies must remain stationary as the drive surface moves beneath the drive heads. This is

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accomplished by suspending the drive head assemblies from an anchor bar over half of the drive surface, as shown schematically in Figure 2.

FIGURE 2.

     Because the drive head assemblies are stationary, there is no need to use air pressure to keep the drive heads at a specific distance from the drive surface. Instead, the entire hard disk drive is vacuum sealed (for example, to 10e-4 torr) to keep out impurities. Because a given drive assembly is inside a channel, the presence of air would cause unwanted turbulent flows within the channel, which could have a detrimental effect on the d...