IP Library Granted Patent US 7,430,086
Granted Patent B2
US 7,430,086 · App. 11/484,540 · Granted Sep 30, 2008

Discrete track recording method, storage apparatus and method of producing storage apparatus

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Quick Facts
Patent No.
US 7,430,086
App. No.
11/484,540
Granted
Sep 30, 2008
Kind
B2
Abstract

A discrete track recording method records information on a magnetic recording medium having mutually adjacent tracks that are separated in advance by a groove. The discrete track recording method carries out a recording using a recording head having a core width in a range greater than or equal to a first value CW 1 and less than a second value CW 2 satisfying CW 1 <CW 2 with respect to a first magnetic recording medium having a first track pitch TP 1 , and carries out a recording a recording head having a core width in a range greater than or equal to the second value CW 2 and less than a third value CW 3 satisfying CW 2 <CW 3 with respect to a second magnetic recording medium having a second track pitch TP 2 satisfying TP 1 <TP 2.

Claims (33)

1. A discrete track recording method for recording information on a magnetic recording medium having mutually adjacent tracks that are separated in advance by a groove, comprising:

rotating a spindle;

carrying out a recording using a first recording head having a core width in a range greater than or equal to a first value CW 1 and less than a second value CW 2 with respect to a first magnetic recording medium fixed on the spindle and having a first track pitch TP 1 , where CW 1 <CW 2 ; and

carrying out a recording using a second recording head having a core width in a range greater than or equal to the second value CW 2 and less than a third value CW 3 with respect to a second magnetic recording medium fixed on the spindle and having a second track pitch TP 2 , where CW 2 <CW 3 and TP 1 <TP 2 .

2. The discrete track recording method as claimed in claim 1 , wherein the first and second recording heads are produced to have a core width with a constant designed value CWD but have different core widths due to inconsistencies introduced during a production process, where CW 1 <CWD<CW 2 .

3. The discrete track recording method as claimed in claim 1 , wherein a groove width of the groove of the first magnetic recording medium and a groove width of the groove of the second magnetic recording medium are mutually different.

4. A storage apparatus for recording information on a magnetic recording medium having mutually adjacent tracks that are separated in advance by a groove, comprising:

a spindle;

a first magnetic recording medium fixed on the spindle and having a first track pitch TP 1 ;

a first recording head, having a core width in a range greater than or equal to a first value CW 1 and less than a second value CW 2 , configured to carry out a recording with respect to the first magnetic recording medium, where CW 1 <CW 2 ;

a second magnetic recording medium fixed on the spindle and having a second track pitch TP 2 ; and

a second recording head, having a core width in a range greater than or equal to the second value CW 2 and less than a third value CW 3 , configured to carry out a recording with respect to the second magnetic recording medium, where CW 2 <CW 3 and TP 1 <TP 2 .

5. The storage apparatus as claimed in claim 4 , wherein the groove is formed in a recording layer of each of the first and second magnetic recording media to a depth which is at least less than or equal to a film thickness of the recording layer.

6. The storage apparatus as claimed in claim 4 , wherein a groove width of the groove of the first magnetic recording medium and a groove width of the groove of the second magnetic recording medium are mutually different.

7. The storage apparatus as claimed in claim 4 , wherein each of the first and second magnetic recording media employs a perpendicular magnetic recording system.

8. A method of producing a storage apparatus for recording information on a magnetic recording medium having mutually adjacent tracks that are separated in advance by a groove, comprising:

installing in the storage apparatus a first recording head, having a core width in a range greater than or equal to a first value CW 1 and less than a second value CW 2 , in combination with a first magnetic recording medium having a first track pitch TP 1 , where CW 1 <CW 2 ; and

installing in the storage apparatus a second recording head, having a core width in a range greater than or equal to the second value CW 2 and less than a third value CW 3 , in combination with a second magnetic recording medium having a second track pitch TP 2 , where CW 2 <CW 3 and TP 1 <TP 2 .

9. The method of producing the storage apparatus as claimed in claim 8 , wherein the first and second recording heads are produced to have a core width with a constant designed value CWD but have different core widths due to inconsistencies introduced during a production process, where CW 1 <CWD<CW 2 .

10. The method of producing the storage apparatus as claimed in claim 8 , wherein a groove width of the groove of the first magnetic recording medium and a groove width of the groove of the second magnetic recording medium are mutually different.

11. The method of producing the storage apparatus as claimed in claim 8 , comprising:

installing only one of a combination of the first recording head and the first magnetic recording medium and a combination of the second recording head and the second magnetic recording medium.

12. The method of producing the storage apparatus as claimed in claim 8 , comprising:

installing both a combination of the first recording head and the first magnetic recording medium and a combination of the second recording head and the second magnetic recording medium.

13. The method of producing the storage apparatus as claimed in claim 8 , comprising:

installing in the storage apparatus a third recording head, having a core width in a range greater than or equal to the third value CW 3 and less than a fourth value CW 4 , in combination with a third magnetic recording medium having a third track pitch TP 3 , where CW 3 <CW 4 and TP 2 <TP 3 ,

said third magnetic recording medium being different from the first and second magnetic recording media.

14. The method of producing the storage apparatus as claimed in claim 8 , wherein each of the first and second magnetic recording media employs a perpendicular magnetic recording system.

15. A method of producing a storage apparatus, comprising:

measuring a core width of a recording head; and

installing in the storage apparatus the recording head in combination with a discrete track recording medium having mutually adjacent tracks separated in advance by a groove with a track pitch corresponding to the core width of the recording head.

16. The method of producing the storage apparatus as claimed in claim 15 , wherein a first recording head having a core width in a range greater than or equal to CW 1 and less than CW 2 is installed in combination with a first recording medium having a track pitch TP 1 , and a second recording head having a core width in a range greater than or equal to CW 2 and less than CW 3 is installed in combination with a second magnetic recording medium having a track pitch TP 2 , where CW 2 <CW 3 and TP 1 <TP 2 .

17. The method of producing the storage apparatus as claimed in claim 16 , wherein first and second recording heads are produced to have a core width with a constant designed value CWD but have different core widths due to inconsistencies introduced during a production process, where CW 1 <CWD<CW 2 .

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 26, 2009
From: FUJITSU LIMITED
To: TOSHIBA STORAGE DEVICE CORPORATION
Reel/Frame 023861/0881 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 11, 2006
From: IZUMI, HARUHIKO
To: FUJITSU LIMITED
Reel/Frame 018101/0838 →