Tape head having sensors proximate to an edge

• US 9,837,104 B1
• Filed: 10/31/2016
• Issued: 12/05/2017
• Est. Priority Date: 10/31/2016
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Biskeborn, Robert G.
• Primary Examiner(s): Evans, Jefferson
• Application Number:
  US15/339,823
• Time in Patent Office: 400 Days
• Field of Search: 360122, 36013021
• CPC Class Codes: G11B 15/43 Control or regulation of mechanical tension of record carrier, e.g. tape tension
• CPC Class Codes: G11B 15/60 Guiding record carrier guiding devices structurally associated with magazines or cassettes G11B23/04
• CPC Class Codes: G11B 15/605 without displacing the guiding means
• CPC Class Codes: G11B 15/62 Maintaining desired spacing between record carrier and head
• CPC Class Codes: G11B 5/008 Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires G11B15/00 G11B19/00 take precedence; bulk transferring of information magnetisation for re-recording G11B5/865; marking record carriers in digital fashion G06K
• CPC Class Codes: G11B 5/00813 magnetic tapes
• CPC Class Codes: G11B 5/1871 Shaping or contouring of the transducing or guiding surface
• CPC Class Codes: G11B 5/255 comprising means for protection against wear in thin film structures G11B5/3106
• CPC Class Codes: G11B 5/31 using thin films G11B5/1274, G11B5/1278, G11B5/1874, G11B5/1875, G11B5/33, G11B5/49 take precedence; magnetic thin film structures H01F10/00
• CPC Class Codes: G11B 5/3906 Details related to the use of magnetic thin film layers or to their effects
• CPC Class Codes: G11B 5/40 Protective measures on heads, e.g. against excessive temperature G11B5/31 takes precedence; protection against wear G11B5/255 ; protective structure of the head: see under structures, e.g. G11B5/3106
• CPC Class Codes: G11B 5/48 Disposition or mounting of heads or head supports relative to record carriers mounting of head within housing G11B5/105; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed driving of both record carriers and head G11B15/18; guiding record carriers G11B15/60; head selecting circuits G11B15/12
• CPC Class Codes: G11B 5/4893 relative to moving tape
• CPC Class Codes: G11B 5/581 maintaining desired contact or spacing by direct interaction of forces generated between heads or supports thereof and record carriers or supports thereof, e.g. attraction-repulsion interactions

Abstract

An apparatus according to one embodiment includes a module having a tape bearing surface, a first edge, and a second edge. A sensor is located in a thin film region of the module. The sensor has a free layer. A distance from the first edge to the free layer is less than a distance from the second edge to the free layer. A method according to another embodiment includes detecting a distance between a free layer of a sensor and an edge closest thereto. The free layer is positioned between an upper shield and the edge. A wrap angle is selected based on the detected distance for inducing tenting of a magnetic recording tape in a region above the free layer when the magnetic recording tape moves over the module.

Claims

1. An apparatus, comprising:

a module having a tape bearing surface, a first edge, and a second edge, wherein a first tape tenting region of the tape bearing surface extends from the first edge along the tape bearing surface toward the second edge;

a guide positioned relative to the first edge for inducing tenting of a moving magnetic recording tape, wherein a location of the tenting is above the first tape tenting region, wherein the tenting includes a peak, a convex region, a concave region, and a point of inflection between the convex region and the concave region, wherein the convex region is located between the peak and the point of inflection; and

a sensor in a thin film region of the module, wherein the sensor has a free layer, wherein a distance from the first edge to the free layer is less than a distance from the second edge to the free layer,

wherein the sensor is positioned below the convex region of the tenting of the moving magnetic recording tape.

2. An apparatus as recited in claim 1, wherein a wrap angle created by the guide is in a range of about 0.1 to about 1.5 degrees.

3. An apparatus as recited in claim 1, wherein the guide is positioned to create the point of inflection of the moving magnetic recording tape at a location above the tape bearing surface that is between the free layer and the second edge, wherein the resulting point of inflection of the moving magnetic recording tape is about midway between the peak of the tenting and a point of closest approach of the moving magnetic recording tape to the tape bearing surface.

4. An apparatus as recited in claim 1, wherein the guide is a second module having transducers.

5. An apparatus as recited in claim 1, wherein the sensor has a reference layer, and a spacer layer positioned between the free layer and the reference layer, wherein the free layer is positioned between the reference layer and the first edge.

6. An apparatus as recited in claim 5, wherein the spacer layer is a tunnel barrier layer.

7. An apparatus as recited in claim 1, wherein the tape bearing surface is planar.

8. An apparatus as recited in claim 1, wherein the distance from the second edge to the free layer is at least as long as the first tape tenting region.

9. An apparatus as recited in claim 1, wherein a media facing side of the sensor is recessed from the tape bearing surface.

10. An apparatus as recited in claim 1, comprising a wear coating on the tape bearing surface.

11. An apparatus as recited in claim 1, further comprising:

a drive mechanism for moving a magnetic medium over the module; and

a controller electrically coupled to the sensor.

12. An apparatus, comprising:

a module having a tape bearing surface, a first edge, and a second edge, wherein a first tape tenting region of the tape bearing surface extends from the first edge along the tape bearing surface toward the second edge;

a guide positioned relative to the first edge for inducing tenting of a moving magnetic recording tape, wherein a location of the tenting is above the first tape tenting region, wherein the tenting includes a peak, a convex region, a concave region and a point of inflection between the convex region and the concave region, wherein the convex region is located between the peak and the point of inflection; and

a sensor in a thin film region of the module, wherein the sensor has a free layer, wherein a distance from the first edge to the free layer is less than a distance from the second edge to the free layer,

wherein the sensor has a reference layer, and a spacer layer positioned between the free layer and the reference layer, wherein the free layer is positioned between the reference layer and the first edge,

wherein the free layer is positioned below the tenting region between the peak and the concave region of the tenting of the moving magnetic recording tape.

13. An apparatus as recited in claim 12, wherein the guide is positioned to create the point of inflection of the magnetic recording tape at a location above the tape bearing surface that is between the free layer and the second edge, wherein the resulting point of inflection of the moving magnetic recording tape is about midway between the peak of the tenting and a point of closest approach of the moving magnetic recording tape to the tape bearing surface.

14. An apparatus as recited in claim 13, wherein a wrap angle created by the guide is in a range of about 0.1 to about 1.5 degrees.

15. An apparatus as recited in claim 12, wherein the spacer layer is a tunnel barrier layer.

16. An apparatus as recited in claim 12, wherein the tape bearing surface is planar.

17. An apparatus as recited in claim 12, wherein the distance from the second edge to the free layer is at least as long as the first tape tenting region.

18. An apparatus as recited in claim 12, wherein a media facing side of the sensor is recessed from the tape bearing surface.

19. An apparatus as recited in claim 12, comprising a wear coating on the tape bearing surface.

20. An apparatus as recited in claim 12, further comprising:

a drive mechanism for moving a magnetic medium over the module; and

a controller electrically coupled to the sensor.

21. A method, comprising:

detecting a distance between a free layer of a sensor and an edge of a tape bearing surface of a module closest thereto, wherein the free layer is positioned between a reference layer and the edge; and

selecting a wrap angle of a magnetic recording tape based on the detected distance for inducing tenting of the magnetic recording tape in a region above the free layer when the magnetic recording tape moves.

22. A method as recited in claim 21, comprising positioning a guide to set the selected wrap angle.

23. A method as recited in claim 21, wherein the distance is measured optically.

24. A method as recited in claim 21, wherein the wrap angle is selected based on a tenting characteristic that changes with changing wrap angle.

25. A method as recited in claim 24, wherein the tenting characteristic is a peak height of a tent, wherein the peak height is in a range of from about 16 to about 26 nanometers from a media facing surface of a tape support surface.