IP Library Granted Patent US 7,417,833
Granted Patent B2
US 7,417,833 · App. 11/111,856 · Granted Aug 26, 2008

Magnetic recording and reproducing apparatus having element for correcting misaligned magnetization direction

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Quick Facts
Patent No.
US 7,417,833
App. No.
11/111,856
Granted
Aug 26, 2008
Kind
B2
Abstract

The invention provides a magnetic recording and reproducing apparatus having magnetic field applying unit applying a magnetic field to a magnetoresistive element to correct a misaligned magnetization direction of the magnetoresistive element. The magnetic field applying unit can be used to correct a misaligned magnetization direction of a free layer of a giant magnetoresistive element. A magnetic field applying unit controller controls the magnetic field applying unit to adjust a magnetization direction and intensity of a magnetic field of the giant magnetoresistive element. The magnetic field applying unit controller can control the magnetic field applying unit to apply a magnetic field only during a data reading time, and to increase the intensity of the application magnetic field during a data re-reading time. The magnetic field applying unit is mounted, corresponding to a head on a suspension that supports a head slider, on a surface of the suspension opposite to the surface on which the head is mounted.

Claims (15)

1. A magnetic recording and reproducing apparatus having a magnetoresistive element, the apparatus comprising an electromagnet for applying a magnetic field by direct current to the magnetoresistive element to correct a misaligned magnetization direction of the magnetoresistive element.

2. The magnetic recording and reproducing apparatus according to claim 1 ,

wherein the electromagnet applies a magnetic field to the magnetoresistive element in the height direction of the magnetoresistive element.

3. The magnetic recording and reproducing apparatus according to claim 1 ,

wherein the magnetoresistive element is a giant magnetoresistive element having a free layer, and the electromagnet corrects a misaligned magnetization direction of the free layer of the giant magnetoresistive element.

4. The magnetic recording and reproducing apparatus according to claim 1 , further comprising a controller that controls the electromagnet to adjust a magnetization direction and magnetic field intensity of the magnetoresistive element.

5. The magnetic recording and reproducing apparatus according to claim 4 ,

wherein the controller controls the electromagnet to generate a magnetic field only during a data reading time.

6. The magnetic recording and reproducing apparatus according to claim 4 ,

wherein the controller controls the electromagnet such that the intensity of a magnetic field generated by the electromagnet is within an intensity range of the magnetic field in which data of a magnetic recording medium is not erased.

7. A magnetic recording and reproducing apparatus having a magnetoresistive element, the apparatus comprising an electromagnet for applying a magnetic field to the magnetoresistive element to correct a misaligned magnetization direction of the magnetoresistive element and a controller that controls the electromagnet to adjust a magnetization direction and magnetic field intensity of the magnetoresistive element,

wherein the controller controls the electromagnet to increase the intensity of an application magnetic field only during a data re-reading time.

8. A magnetic recording and reproducing apparatus having a magnetoresistive element, the apparatus comprising an electromagnet for applying a magnetic field to the magnetoresistive element to correct a misaligned magnetization direction of the magnetoresistive element and a controller that controls the electromagnet to adjust a magnetization direction and magnetic field intensity of the magnetoresistive element,

wherein the controller controls the electromagnet to increase the intensity of the magnetic field of the electromagnet during a period other than a reading time, and

during a reading time, the controller controls the electromagnet to read data without applying the magnetic field, and to detect an error rate, thereby setting an intensity range of the magnetic field applied by the electromagnet.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 26, 2009
From: FUJITSU LIMITED
To: TOSHIBA STORAGE DEVICE CORPORATION
Reel/Frame 023861/0881 →