Low drag liquid bearing recording head

• US 5,526,204 A
• Filed: 02/28/1995
• Issued: 06/11/1996
• Est. Priority Date: 12/20/1989
• Status: Expired due to Fees

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Conner Peripherals Incorporated (Whitehouse Group Ltd.)
• Inventors: Danson, David P., Repphun, William, Wong, Walter, Lemke, James U., French, William, Goker, Turguy
• Primary Examiner(s): Wolff, John H.
• Application Number:
  US08/396,273
• Time in Patent Office: 469 Days
• Field of Search: 360/97.02, 360/97.01, 360/102-104
• US Class Current: 360/97.02
• CPC Class Codes: G11B 5/6005 Specially adapted for spacing from a rotating disc using a fluid cushion

Abstract

A read/write head for an information recording apparatus having a liquid bearing lubricant between a rotating storage medium and the read/write head is disclosed. The head is provided an actuator to position the read/write head over the rotating storage medium. The head includes a slider body having at least a first and second regions; and an interface element comprising a transducer interacting with the storage medium and mounted on the first region of the slider body. A relative motion exists between the head and the rotating storage medium and the slider body is supported by the liquid bearing lubricant during such motion, such that the first region of the slider body is supported at a first distance above the storage medium, and the second region of the slider body is supported at a second distance above the storage medium, whereby the first region of the slider body has a substantially higher drag than the second region when the head moves relative to the storage medium.

Claims

1. A read/write head for an information recording apparatus, the information recording apparatus comprising a housing, a spin rotator mounted in the housing, a storage disk mounted on the spin rotator, a non-Newtonian liquid bearing lubricant disposed between the storage disk and the read/write head, and means for supporting and positioning the read/write head with respect to said disk to position the read/write head over the storage disk, the head comprising:

a slider body, the slider body having at least a first and second regions; and

an interface element, mounted on the first region of the slider body, the interface element comprising a transducer interacting with the storage disk;

wherein upon rotation of the storage disk by the spin rotator, the first region of the slider body supports the slider body at a first distance above the storage disk and exhibits a first shear stress in the non-Newtonian regime on the liquid bearing, and the second region of the slider body supports the slider body at a second distance above the storage disk, the second distance being greater than the first distance such that the second region exhibits a second shear stress in the Newtonian regime, whereby the first region of the slider body has a substantially higher drag than the second region such that the total drag of the slider body is substantially reduced.

2. The read/write head of claim 1 wherein the slider body includes a top and bottom surface, and a first end and a second end, wherein the first region of the slider body includes at least a first pad on the bottom surface at the first end of the slider body, and the second region of the slider body includes at least a second pad on the bottom surface of the slider body at the second end of the slider body.

3. The read/write head of claim 2 wherein the second pad includes a leading edge and a trailing edge, the leading edge preceding the trailing edge over a portion of the storage disk upon rotation of the storage disk, the leading edge being beveled.

4. The read/write head of claim 2 wherein the second end of the slider body includes said second pad, and further includes a third pad, said second and third pads each having a beveled edge oriented to be the leading edge of each said pad with respect to the storage disk relative to the movement of the storage disk when the storage disk is rotated by the spin rotator.

5. The read/write head of claim 1 wherein the head has a mass, and a center of mass positioned at a height above the storage disk, and the actuator includes a suspension element supplying a load to the read/write head with respect to the storage disk, the suspension element being attached to the head such that the attachment is at the height of the center of mass.

6. A recording head for a disk drive, the disk drive including a rotatable storage disk, a spin rotator for supporting and rotating said disk, means for positioning the head relative to said disk, the drive further including a non-Newtonian liquid bearing lubricant on the surface of said disk between said disk and the head, the head comprising:

a slider body, the slider body having a first end and a second end, the first and second ends of the slider body being supported over said disk by said liquid bearing lubricant; and

a transducer element, mounted on the first region of the slider body;

wherein upon rotation of said disk by the spin rotator, the first end of the slider body supports the slider body in said liquid bearing lubricant at a first distance from said disk and the second end of the slider body supports the slider body at a second distance from said disk, the second distance being greater than the first distance, such that said first end of the slider body exhibits a greater shear rate on said liquid bearing lubricant than said second end, said shear rate of said first end being in the non-Newtonian regime, and said second end exhibit said shear rate on said liquid bearing in the Newtonian regime, wherein the total drag of the head is reduced.

7. The head of claim 6 wherein the difference in the first distance and the second distance is about 0.1-5.5 micro inches.

8. The head of claim 6 wherein the ratio of the distance between the disk and the second end to the distance between the disk and the first end is between 3:

1 and 15;

1.

9. The head of claim 6 wherein the first end of the slider body contributes at least 60% of the total drag of the head in the fluid.

10. The head of claim 6 wherein the distance between the disk and the first end is between 0.1 and 1.2 microinches.

11. The head of claim 6 wherein the distance between the disk and the second end is between 1.0 and 7.0 microinches.

12. In a disk drive including a disk, means for rotating the disk, an actuator, swing arm, and a suspension element, and a non-Newtonian liquid lubricant on the disk, a recording head mounted on the suspension element, the actuator arranged to position the recording head with respect to the disk, the recording head comprising:

a body having a bottom surface, the bottom surface having an area, the body having at least a first pad, a second pad and a third pad, each pad supporting the body in the non-Newtonian liquid lubricant when the disk is rotated by the means for rotating, each pad having a bottom surface with an area, the area of the bottom surface of each of said pads being at least one one-thousandth the area of the area of the bottom surface of the body; and

a magnetic core and a coil assembly mounted adjacent to said first pad;

wherein, upon rotation of the disk, said second and third pads support the recording head in the non-Newtonian liquid lubricant at a distance from said disk which is in a range of greater than one to about six times greater than a distance between the first pad and the disk such that the shear rate of the first pad is in the non-Newtonian regime and greater than the shear rate of the second and third pads, the shear rate of the second and third pads being in the Newtonian regime, and the drag at said second and third pads is less than the drag at said first pad, such that the total drag of the recording head is reduced.

13. The recording head of claim 12 wherein the body includes a top, a bottom, a leading edge and a trailing edge, and wherein said second and third pads are positioned at the leading edge of the body with respect to the rotation of the disk, and the first pad is positioned at the trailing edge of the body.

14. The head of claim 13 wherein the second and third pads include inclined ramps.

15. A disk drive, comprising:

a disk having a surface;

means for supporting and rotating the disk;

a non-Newtonian liquid bearing on the surface of the disk;

a read/write head having a first head region and a second head region, and a core positioned adjacent to the first head region; and

means for positioning side head with respect to the disk, the means cooperating with the non-Newtonian liquid bearing to support the read/write head such that

the first head region passes through the non-Newtonian liquid bearing when the disk is rotating and exhibits shear characteristics in a non-Newtonian regime within the liquid;

the second head region passes through the non-Newtonian liquid bearing when the disk is rotating and exhibits shear characteristics within a Newtonian regime within the non-Newtonian liquid bearing wherein the total drag of the head is reduced.

16. The head of claim 15 wherein the first region includes two pads positioned to support the head in the liquid bearing, and said pads have a beveled leading edge.

17. The head of claim 15 wherein the first region and the second region each include two pads positioned to support the head in the non-Newtonian liquid bearing and said two pads at the first region have a beveled leading edge.

18. The head of claim 15 including two pads positioned at the second region of the head, each pad at the first region including a tapered leading edge, and two pads are positioned at the first region of the head, one of the pads at the second region having a recording gap formed therein, the gap being coupled to the core, the other of the pads at the first region of the head having a tapered leading edge.