Disk drive with head-disk interaction sensor integrated with suspension

• US 20050057834A1
• Filed: 09/17/2003
• Published: 03/17/2005
• Est. Priority Date: 09/17/2003
• Status: Active Grant

• Current Assignee: HGST Netherlands B.V. (Western Digital Corporation)
• Original Assignee: Hitachi Global Storage Technologies Netherlands BV (Western Digital Corporation)
• Inventors: Zeng, Qinghua, Hirano, Toshiki, Nayak, Ullal Vasant
• Granted Patent: US 7,312,941 B2
• Time in Patent Office: Days
• US Class Current: 360/31
• CPC Class Codes: G11B 19/04 Arrangements for preventing, inhibiting, or warning against double recording on the same blank or against other recording or reproducing malfunctions
• CPC Class Codes: G11B 5/012 Recording on, or reproducing or erasing from, magnetic disks G11B17/00, G11B19/00 take precedence
• CPC Class Codes: G11B 5/4826 Mounting, aligning or attachment of the transducer head relative to the arm assembly, e.g. slider holding members, gimbals, adhesive G11B5/484 takes precedence; details of head housings or structures G11B5/10, G11B5/127; adjustment relative to the record carrier G11B5/56
• CPC Class Codes: G11B 5/4833 Structure of the arm assembly, e.g. load beams, flexures, parts of the arm adapted for controlling vertical force on the head G11B5/484 takes precedence
• CPC Class Codes: G11B 5/6005 Specially adapted for spacing from a rotating disc using a fluid cushion

Abstract

A Hard Disk Drive (HDD) includes a write-inhibit signal that is generated by a head-disk interaction sensor during a write process that is integrated with a suspension of the HDD when fly-height modulation of the slider is detected during a write process. The suspension load beam includes a dimple and a laminated flexure. The laminated flexure includes a surface that is adapted to receive a slider and a surface that is adapted to contact the dimple. The head-disk interaction sensor is fabricated as part of the laminations of the flexure. The head-disk interaction sensor can be an accelerometer that senses an acceleration of the flexure when the slider contacts the disk of the disk drive and/or a pressure sensor that senses a pressure between the flexure and the dimple when the slider contacts the disk. A write-inhibit circuit is responsive to the sensor signal by inhibiting the write process.

Claims

1. A disk drive, comprising:

a suspension load beam having a dimple; and

a laminated flexure coupled to the suspension load beam, the flexure having a surface adapted to receive a slider and a surface adapted to contact the dimple, the flexure including a head-disk interaction sensor outputting a sensor signal when the slider contacts a disk of the disk drive.

2. The disk drive according to claim 1, wherein the head-disk interaction sensor is an accelerometer sensing an acceleration of the flexure generated by the slider contacting the disk of the disk drive.

3. The disk drive according to claim 2, wherein the head-disk interaction sensor further includes a pressure sensor sensing a pressure between the flexure and the dimple generated by the slider contacting the disk of the disk drive.

4. The disk drive according to claim 2, wherein the accelerometer includes a piezoelectric material layer and a conductive material layer, the piezoelectric material layer and the conductive material layer each being formed as a layer of the laminated flexure and each being patterned to substantially correspond to a top surface of a back portion of the slider.

5. The disk drive according to claim 1, wherein the head-disk interaction sensor is a pressure sensor sensing a pressure between the flexure and the dimple generated by the slider contacting the disk of the disk drive.

6. The disk drive according to claim 5, wherein the pressure sensor includes a piezoelectric material layer and a conductive material layer, the piezoelectric material layer and the conductive material layer each being formed as a layer of the laminated flexure and each being patterned to substantially correspond to a surface region of the flexure corresponding to the dimple.

7. The disk drive according to claim 6, wherein the piezoelectric material layer generates a voltage between a top portion and a bottom portion of the piezoelectric material layer when the slider contacts the disk of the disk drive, the voltage generated between the top portion and the bottom portion of the piezoelectric material layer corresponding to a magnitude of a force with which the slider contacts the disk of the disk drive.

8. The disk drive according to claim 6, wherein the piezoelectric material layer and the conductive material layer are patterned to be a substantially square shape.

9. The disk drive according to claim 6, wherein the piezoelectric material layer and the conductive material layer are patterned to be a substantially circular shape.

10. The disk drive according to claim 5, wherein the pressure sensor includes a piezoelectric material layer and a conductive material layer that are each formed as a layer of the laminated flexure, the piezoelectric material layer and the conductive material layer each being patterned to form a first region and a second region, the first and second regions respectively corresponding to a front portion and a back portion of the slider and respectively corresponding to first and second surface regions of the surface of the flexure adapted to contact the dimple.

11. The disk drive according to claim 10, wherein the first region of the piezoelectric material layer generates a first voltage between a top portion and a bottom portion of the first region of the piezoelectric material layer when the slider contacts the disk of the disk drive, the second region of the piezoelectric material layer generates a second voltage between a top portion and a bottom portion of the second region of the piezoelectric material layer when the slider contacts the disk of the disk drive, the first and second voltages respectively generated between the top portions and the bottom portions of the first and second regions of the piezoelectric material layer each corresponding to a magnitude of a force with which the slider contacts the disk of the disk drive, and

wherein a pitch mode of the slider is determined based on a difference between the first voltage and the second voltage.

12. The disk drive according to claim 10, wherein the first region of the piezoelectric material layer generates a first voltage between a top portion and a bottom portion of the first region of the piezoelectric material layer when the slider contacts the disk of the disk drive, the second region of the piezoelectric material layer generates a second voltage between a top portion and a bottom portion of the second region of the piezoelectric material layer when the slider contacts the disk of the disk drive, the first and second voltages respectively generated between the top portions and the bottom portions of the first and second regions of the piezoelectric material layer each corresponding to a magnitude of a force with which the slider contacts the disk of the disk drive, and

wherein a first bending mode of a body of the slider body can be determined based on a sum of the first and second voltages.

13. The disk drive according to claim 1, further comprising a write-inhibit circuit responsive to the sensor signal by inhibiting a write operation of the disk drive.

14. The disk drive according to claim 13, wherein the write-inhibit circuit includes a filter circuit conditioning the sensor signal.

15. The disk drive according to claim 14, wherein the filter circuit is a low-pass filter having a passband that is greater than about 20 kHz.

16. The disk drive according to claim 14, wherein the filter circuit is a high-pass filter having a passband that is less than about 2 MHz.

17. The disk drive according to claim 14, wherein the filter circuit is a bandpass filter having a passband between about 20 kHz and about 2 MHz.

18. The disk drive according to claim 14, wherein the filter circuit is a bandpass filter having a passband corresponding to about a pitch frequency of the slider.

19. The disk drive according to claim 14, wherein the filter circuit is a passband filter having a narrow passband at about 200 kHz.

20. The disk drive according to claim 14, wherein the filter circuit is a bandpass filter having a passband corresponding to about a bending mode frequency of a body of the slider.

21. The disk drive according to claim 14, wherein the filter circuit is a passband filter having a narrow passband at about 1.6 MHz.

22. The disk drive according to claim 14, wherein the filter circuit is a passband filter having a passband that includes about 200 kHz and about 1.6 MHz.