Stray field detector, magnetic disk drive, and method of head escaping

一种磁盘驱动器、杂散磁场的技术,应用在正交磁化磁头、磁记录头、在磁盘上信息的记录等方向,能够解决妨碍磁盘驱动器操作、信息丢失、伺服标记和磁道及扇区识别信号丢失等问题,达到高度可靠磁盘驱动器、防止退磁或消磁的效果

Inactive Publication Date: 2006-03-15
HITACHI GLOBAL STORAGE TECH NETHERLANDS BV
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

If this phenomenon occurs, the written information will be lost and, except in extremely unusual cases, even servo marks and track and sector operation

Method used

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  • Stray field detector, magnetic disk drive, and method of head escaping
  • Stray field detector, magnetic disk drive, and method of head escaping
  • Stray field detector, magnetic disk drive, and method of head escaping

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Embodiment Construction

[0038] Embodiments of the present invention are illustrated using a perpendicular disk drive. refer to figure 1 and figure 2 A stray magnetic field detection method as a first embodiment of the present invention will be described. Such as figure 1 The illustrated disk drive includes: a magnetic recording medium 10 , which is rotated by a motor 12 ; a magnetic head 140 , which performs reading / writing to the magnetic recording medium 10 ; and a stray magnetic field detection unit 30 . The magnetic recording medium 10 is a two-layer perpendicular recording medium having a magnetic recording layer and a soft underlayer. The magnetic head 140 includes a single pole type magnetic head having a main pole and a return magnetic pole as a writing head, and an MR head using a magnetoresistance effect such as a giant magnetoresistance effect and a tunneling magnetoresistance effect as a read head. The magnetic head 140 is mounted on a slider in front of the suspension 151 and posi...

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Abstract

Embodiments of the invention prevent demagnetization or degaussing of recorded magnetizations, even if a stray field is applied. In one embodiment, an output of a read head including a magneto-resistive effect element is inputted to a stray field detector through a DC amplifier and a DC filter. The stray field detector monitors dc components of the output from the read head, and escapes a head from above a magnetic recording medium.

Description

technical field [0001] The present invention relates to a stray magnetic field detection method, a stray magnetic field detector, and a magnetic disk drive against stray magnetic fields in a data reading / writing device, wherein the data reading / writing device magnetically reads Signal written in the thickness direction. Background technique [0002] refer to Figure 14 and Figure 15 As an example, a perpendicular disk drive is used to illustrate conventional recording techniques. A perpendicular magnetic disk drive is a magnetic disk drive having a perpendicular magnetic recording medium, a read / write head, etc., and performs reading / writing by a perpendicular magnetic recording system. Unlike a conventional longitudinal recording system, a perpendicular magnetic recording system forms a magnetization recorded in the thickness direction of a recording medium. exist Figure 14 Among them, the perpendicular magnetic recording medium 10 includes a recording layer 101 having...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): G11B5/02G11B21/00
CPCG11B5/1278G11B5/012G11B27/36G11B5/3903G11B5/02G11B2005/0029G11B2220/20G11B2005/0016
Inventor 前田英明滨口雄彦菊川敦铃木干夫沈丽萍荒井礼子
Owner HITACHI GLOBAL STORAGE TECH NETHERLANDS BV
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