METHODS FOR SELECTING WRAP ANGLE FOR INDUCING TAPE TENTING ABOVE TRANSDUCER

• US 20180158478A1
• Filed: 12/06/2016
• Published: 06/07/2018
• Est. Priority Date: 12/06/2016
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Biskeborn, Robert G., Czarnecki, W. Stanley, Lo, Calvin S.
• Granted Patent: US 10,418,059 B2
• Time in Patent Office: Days
• 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 15/62 Maintaining desired spacing between record carrier and head
• CPC Class Codes: G11B 15/64 by fluid-dynamic spacing
• CPC Class Codes: G11B 5/00813 magnetic tapes
• CPC Class Codes: G11B 5/00826 comprising a plurality of single poles or gaps or groups thereof operative at the same time
• CPC Class Codes: G11B 5/187 Structure or manufacture of the surface of the head in physical contact with, or immediately adjacent to the recording medium; Pole pieces; Gap features G11B5/265, G11B5/29 , G11B5/31 take precedence
• 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 5/4893 relative to moving tape
• CPC Class Codes: G11B 5/60 Fluid-dynamic spacing of heads from record-carriers

Abstract

In one general embodiment, a method includes determining a distance from a transducer of a module to an edge of the module closest thereto, and selecting a wrap angle based on the determined distance for inducing tenting of a moving magnetic recording tape in a region above the transducer. In another general embodiment, a method includes running a magnetic recording tape over a tape bearing surface having at least one edge, and detecting signals from the tape at differing wrap angles for estimating a height of tenting of the tape above a transducer at each of the wrap angles. A wrap angle is selected to provide about a predefined height of tenting of the tape above the transducer.

Claims

1. A method, comprising:

determining a distance from a transducer of a module to an edge of the module closest thereto; and

selecting a wrap angle based on the determined distance for inducing tenting of a moving magnetic recording tape directly above the transducer whereby a resulting tent of the moving magnetic recording tape extends from the edge of the module to a minima with a tent apex therebetween, wherein the minima is at a point of closest approach of the moving magnetic recording tape to a tape bearing surface of the module nearest the tent apex.

2. A method as recited in claim 1, comprising positioning a guide to set the selected wrap angle.

3. A method as recited in claim 1, comprising positioning a second module to set the selected wrap angle.

4. A method as recited in claim 1, wherein the distance is measured optically.

5. A method as recited in claim 1, wherein the distance is measured mechanically.

6. A method as recited in claim 1, wherein the wrap angle is selected to produce a predetermined tenting characteristic.

7. A method as recited in claim 6, wherein the tenting characteristic is a height of the tent apex.

8. A method as recited in claim 7, wherein the height of the tent apex is in a range of from about 5 to about 30 nanometers from a media facing surface of a tape support surface.

9. A method as recited in claim 6, wherein the tenting characteristic is a length of a tent.

10. A method as recited in claim 6, comprising moving the tape over the module for an amount of time sufficient to cause detectable wear on the edge;

and adjusting the wrap angle to produce the predetermined tenting characteristic.

23. A method as recited in claim 1, wherein the wrap angle is selected to provide about a predefined height of tenting of the moving magnetic recording tape above a tape bearing surface of the transducer.

24. A method as recited in claim 23, wherein a tape bearing surface of the module is planar.

25. A method as recited in claim 1, wherein the transducer is a TMR sensor.

26. A method as recited in claim 8, wherein the transducer is recessed from a plane of the media facing surface, wherein the height of the tent apex is in a range of from about 5 to about 30 nanometers from the transducer.

11. (canceled)

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27. A computer program product for determining a wrap angle, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, wherein the computer readable storage medium is not a transitory signal per se, the program instructions executable by a processor to cause the processor to perform a method comprising:

determining, by the processor, a distance from a transducer of a module to an edge of the module closest thereto; and

,

selecting, by the processor, a wrap angle based on the determined distance for inducing tenting of a moving magnetic recording tape directly above the transducer whereby a resulting tent of the moving magnetic recording tape extends from the edge of the module to a minima with a tent apex therebetween, wherein the minima is at a point of closest approach of the moving magnetic recording tape to a tape bearing surface of the module nearest the tent apex.

28. A computer program product as recited in claim 27, comprising positioning, by the processor, a guide to set the selected wrap angle.

29. A computer program product as recited in claim 27, comprising positioning, by the processor, a second module to set the selected wrap angle.

30. A computer program product as recited in claim 27, wherein the distance is measured optically.

31. A computer program product as recited in claim 27, wherein the wrap angle is selected to produce a predetermined tenting characteristic.

32. A computer program product as recited in claim 31, wherein the tenting characteristic is a height of the tent apex.

33. A computer program product as recited in claim 32, wherein the height of the tent apex is in a range of from about 5 to about 30 nanometers from a media facing surface of a tape support surface.

34. A computer program product as recited in claim 27, wherein the wrap angle is selected to provide about a predefined height of tenting of the moving magnetic recording tape above a tape bearing surface of the transducer.