Signal-based tape wrap angle setting for flat contour linear tape recording heads

• US 6,760,177 B2
• Filed: 08/23/2001
• Issued: 07/06/2004
• Est. Priority Date: 08/23/2001
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Biskeborn, Robert Glenn
• Primary Examiner(s): Hudspeth, David
• Assistant Examiner(s): DAVIDSON, DAN
• Application Number:
  US09/938,627
• Publication Number:
  US 20030039045A1
• Time in Patent Office: 1,048 Days
• Field of Search: 360/71, 360/90, 360/130.21, 360/130.31
• US Class Current: 360/71
• CPC Class Codes: G11B 15/62 Maintaining desired spacing between record carrier and head
• CPC Class Codes: G11B 5/00813 magnetic tapes
• CPC Class Codes: G11B 5/584 for track following on tapes

Abstract

In an essentially flat contour linear tape recording head, a nominal tape wrap angle exists at which reading signals from the magnetic tape ceases and/or commences. This nominal tape wrap angle can be easily determined by monitoring a prerecorded signal, such as the servo track signal, while the tape wrap angle is adjusted. When the signal ceases (or starts, depending upon the direction of adjustment) an initial position of the tape movement control device relative to the tape wrap angle is identified. At this initial position it is known that the tape wrap angle is at its nominal value, such as approximately 0.1°. Thereafter, the tape movement control device can be knowingly adjusted with a calibrated indicator to accurately and quickly achieve a desired final tape wrap angles.

Claims

1. A method for setting the tape wrap angle of a flat contour linear tape recording head, comprising the steps of:

adjusting a tape movement control device to move a magnetic tape from a first position to an initial position relative to a flat upper surface of the tape recording head that corresponds to a nominal tape wrap angle;

determining said initial position by monitoring a signal from said tape; and

adjusting said calibrated tape movement control device to move said tape from said initial position to a second position that corresponds to a desired tape wrap angle.

2. A method for setting the tape wrap angle as described in claim 1 wherein said nominal tape wrap angle corresponds to a tape position in which said signal ceases.

3. A method for setting the tape wrap angle as described in claim 2, wherein said tape movement control device is set in said first position wherein the tape wrap angle of said tape is greater than said nominal tape wrap angle.

4. A method for setting the tape wrap angle as described in claim 3 wherein said tape movement control device is adjusted from said first position in a manner that reduces the tape wrap angle of said tape, and said signal is monitored while said tape movement control device is adjusted.

5. A method for setting the tape wrap angle as described in claim 4 wherein said tape movement control device is adjusted to increase the tape wrap angle from said initial position to said second position.

6. A method for setting the tape wrap angle as described in claim 5 wherein said signal is a servo track signal.

7. A method for setting the tape wrap angle as described in claim 6 wherein said tape movement control device is a tape roller that is mounted on a calibrated movable excentric axle.

8. A method for setting the tape wrap angle as described in claim 1, wherein said step of monitoring said signal includes the step of determining when said signal commences.

9. A method for setting the tape wrap angle as described in claim 8, wherein said tape movement control device is set in said first position wherein the tape wrap angle of said tape is less than said nominal tape wrap angle.

10. A method for setting the tape wrap angle as described in claim 9 wherein said tape movement control device is adjusted from said first position in a manner that increases the tape wrap angle of said tape, and said signal is monitored while said tape movement control device is adjusted.

11. A method for setting the tape wrap angle as described in claim 10 wherein said tape movement control device is adjusted to increase the tape wrap angle from said initial position to said second position.

12. A method for setting the tape wrap angle as described in claim 11 wherein said signal is a servo track signal.

13. A method for setting the tape wrap angle as described in claim 12 wherein said tape movement control device is a tape roller that is mounted on a calibrated movable excentric axle.