Magnetic head assembly with at least one guide block set back from sliding surface of servo signal recording head

• US 7,486,479 B2
• Filed: 04/19/2004
• Issued: 02/03/2009
• Est. Priority Date: 05/15/2003
• Status: Expired due to Fees

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Hashimoto, Akihiro, Nakao, Toru, Izumida, Takahisa
• Primary Examiner(s): Renner; Craig A
• Application Number:
  US10/826,505
• Publication Number:
  US 20040228034A1
• Time in Patent Office: 1,751 Days
• Field of Search: 360/130.21, 360/129, 360/122
• US Class Current: 360/130.21
• CPC Class Codes: G11B 5/1871 Shaping or contouring of the transducing or guiding surface
• CPC Class Codes: G11B 5/584 for track following on tapes

Abstract

A magnetic head assembly to record servo signals, that serves for positioning of data recording magnetic heads and data reproducing magnetic heads, on magnetic tapes includes a servo signal recording head of which sliding surface has a magnetic gap embedded thereon in order to record the servo signals onto a magnetic tape and guide blocks which are set adjacent to at least one of the up-stream position or the down-stream position of a line of magnetic tape passing the servo signal recording head and are slightly set back from the sliding surface of the recording head so that said magnetic tape slides an edge of the servo signal recording head and an edge of the guide block.

Claims

1. A magnetic head assembly to record servo signals, that serves for positioning of data recording magnetic heads and data reproducing magnetic heads, on a magnetic tape comprising:

a servo signal recording head wherein a sliding surface of said servo signal recording head has a magnetic gap embedded thereon in order to record said servo signals onto the magnetic tape, and

a guide block which is set adjacent to a position of up-stream of a line of said magnetic tape passing said servo signal recording head and is slightly set back from said sliding surface of said servo signal recording head so that said magnetic tape slides on an edge of said servo signal recording head and on an outer edge of said guide block, the edge of said servo signal recording head and the outer edge of said guide block being chamfered,

wherein a wrap angle (θ

1) between said sliding surface of said recording head and a plane formed by the edge of said servo signal recording head and said outer edge of said guide block is in a range of 1.0 to 6.0 degrees.

2. A magnetic head assembly according to claim 1,

wherein said guide block has at least at a portion of said outer edge made of a material which has hardness of more than 1200 Vickers hardness.

3. A magnetic head assembly according to claim 1, wherein said guide block is made of a material of Al₂O₃.TiC.

4. A magnetic head assembly according to claim 1, wherein said guide block is surface-finished for hardening.

5. A magnetic tape servo writer having a magnetic head assembly according to claim 1,

wherein another wrap angle (θ

2) between a plane formed by the edge of said servo signal recording head and said outer edge of said guide block and a plane formed by the outer edge of said guide block and an edge of a tape guide which is adjacent to said guide block along a passing line of said magnetic tape is 0.5 to 2.0 degrees.

6. A magnetic head assembly according to claim 1, wherein the magnetic tape comes into contact with only the outer edge of the guide block.

7. A magnetic head assembly according to claim 1, wherein the magnetic tape slides on the sliding surface of the servo signal recording head.

8. A magnetic head assembly according to claim 1, wherein the magnetic tape is not parallel to an uppermost surface of the guide block.

9. A magnetic head assembly according to claim 1, wherein the recording head includes a planar surface as the sliding surface and wherein the guide block is displaced from the planar surface, the guide block having a guide block planar surface substantially parallel to the planar sliding surface.

10. A magnetic head assembly according to claim 1, wherein the guide block is comprised of an inner wall, which is closest to the servo signal recording head, and an outer wall, which is farthest away from the servo signal recording head, wherein the outer edge is formed on the outer wall.

11. A magnetic head assembly according to claim 10, wherein the inner wall directly abuts the servo signal recording head.

12. A magnetic head assembly to record servo signals, that serves for positioning of data recording magnetic heads and data reproducing magnetic heads, on a magnetic tape comprising:

a servo signal recording head wherein a sliding surface of said servo signal recording head has a magnetic gap embedded thereon in order to record said servo signals onto the magnetic tape, and

a guide block which is set adjacent to a position of down-stream of a line of said magnetic tape passing said servo signal recording head and is slightly set back from said sliding surface of said servo signal recording head so that said magnetic tape slides on an edge of said servo signal recording head and on an outer edge of said guide block, the edge of said servo signal recording head and the outer edge of said guide block being chamfered,

wherein a wrap angle (θ

1) between said sliding surface of said recording head and a plane formed by the edge of said servo signal recording head and said outer edge of said guide block is in a range of 1.0 to 6.0 degrees.

13. A magnetic head assembly according to claim 12,

wherein said guide block has at least at a portion of said outer edge made of a material which has hardness of more than 1200 Vickers hardness.

14. A magnetic head assembly according to claim 12, wherein said guide block is made of a material of Al₂O₃.TiC.

15. A magnetic head assembly according to claim 12,

wherein said guide block is surface-finished for hardening.

16. A magnetic tape servo writer having a magnetic head assembly according to claim 12,

wherein another wrap angle (θ

2) between a plane formed by the edge of said servo signal recording head and said outer edge of said guide block and a plane formed by the outer edge of said guide block and an edge of a tape guide which is adjacent to said guide block along a passing line of said magnetic tape is 0.5 to 2.0 degrees.

17. A magnetic head assembly to record servo signals, that serves for positioning of data recording magnetic heads and data reproducing magnetic heads, on a magnetic tape comprising:

a servo signal recording head wherein a sliding surface of said servo signal recording head has a magnetic gap embedded thereon in order to record said servo signals onto the magnetic tape, and

two guide blocks of which one guide block is set adjacent to a position of up-stream of a line of said magnetic tape passing said servo signal recording head, the other guide block is set adjacent to a position of down-stream of a line of said magnetic tape passing said servo signal recording head and both guide blocks are slightly set back from said sliding surface of said servo signal recording head so that said magnetic tape slides on a downstream edge and an upstream edge of said servo signal recording head and on an outer edge of each said guide block, wherein the downstream edge and the upstream edge of said servo signal recording head and the outer edge of each said guide block are chamfered,

wherein a wrap angle (θ

1) between said sliding surface of said recording head and a plane formed by at least one of the downstream edge and the upstream edge of said servo signal recording head and said outer edge of at least one of said guide blocks is in a range of 1.0 to 6.0 degrees.

18. A magnetic head assembly according to claim 17,

wherein each said guide block has at least at a portion of said outer edge made of a material which has hardness of more than 1200 Vickers hardness.

19. A magnetic head assembly according to claim 17, wherein each said guide block is made of a material of Al₂O₃.TiC.

20. A magnetic head assembly according to claim 17, wherein each said guide block is surface-finished for hardening.

21. A magnetic tape servo writer having a magnetic head assembly according to claim 17,

wherein another wrap angle (θ

2) between a plane formed by at least one of the downstream edge and the upstream edge of said servo signal recording head and said outer edge of at least one of said guide blocks and a plane formed by the outer edge of said at least one of said guide blocks and an edge of a tape guide which is adjacent to said at least one of said guide blocks along a passing line of said magnetic tape is 0.5 to 2.0 degrees.

22. A servo signal writer, comprising:

a magnetic tape;

a magnetic tape driving assembly,

a controller which controls the tape driving assembly, and

a magnetic head assembly to record servo signals, that serves for positioning of data recording magnetic heads and data reproducing magnetic heads, on the magnetic tape, the magnetic head assembly comprising;

a servo signal recording head wherein a sliding surface of said servo signal recording head has a magnetic gap embedded thereon in order to record said servo signals onto the magnetic tape, and

a guide block which is set adjacent to a position of up-stream of a line of said magnetic tape passing said servo signal recording head and is slightly set back from said sliding surface of said servo signal recording head so that said magnetic tape slides on an edge of said servo signal recording head and on an outer edge of said guide block, wherein the magnetic tape comes into contact with only the outer edge of the guide block;

wherein the recording head includes a planar surface as the sliding surface and wherein an uppermost surface of the guide block is substantially parallel to the planar sliding surface.

23. The servo signal writer according to claim 22, wherein the magnetic tape slides on the sliding surface of the servo signal recording head.

24. The servo signal writer according to claim 22, wherein the magnetic tape is not parallel to the uppermost surface of the guide block.