Apparatus and method for near contact magnetic recording

• US 5,850,317 A
• Filed: 03/16/1993
• Issued: 12/15/1998
• Est. Priority Date: 10/31/1988
• Status: Expired due to Fees

• Current Assignee: Hitachi Global Storage Technologies Netherlands BV (Western Digital Corporation)
• Original Assignee: International Business Machines Corporation
• Inventors: Keller, Christopher Guild, Larson, Thomas Scott, Gregory, Thomas Allen
• Primary Examiner(s): HEINZ, ALLEN J
• Application Number:
  US08/032,511
• Time in Patent Office: 2,100 Days
• Field of Search: 360/103, 360/97.02, 360/97.01
• US Class Current: 360/97.01
• CPC Class Codes: G11B 15/62 Maintaining desired spacing between record carrier and head
• CPC Class Codes: G11B 23/505 of disk carriers
• CPC Class Codes: G11B 25/043 using rotating discs
• CPC Class Codes: G11B 33/1406 Reducing the influence of the temperature
• CPC Class Codes: G11B 33/148 Reducing friction, adhesion, drag
• CPC Class Codes: G11B 5/6005 Specially adapted for spacing from a rotating disc using a fluid cushion
• CPC Class Codes: H02J 13/00012 using an auxiliary transmission line

Abstract

A rotating magnetic storage device is shown wherein the transducer and media are separated during operation by a thin film of low viscosity liquid lubricant that is recirculated from a reservoir within the head-media enclosure. Lubricant recirculation can be effected by capillary action using a wick, mechanical pumping and metering or distillation techniques. As compared to devices using air bearing separation, the transducer carrying slider has very small bearing surfaces which may be in the form of narrow rails or small depending foot elements. This enables fly heights. of 2 microinches using a film of one micron thickness.

Claims

1. A rotating magnetic memory device comprising:

a rotating storage medium presenting a rotating magnetic data surface;

a magnetic transducer;

recirculating means for maintaining a recirculating film of liquid lubricant on said magnetic data surface; and

a head-disk enclosure surrounding said rotating storage medium and said magnetic transducer, said magnetic transducer being supported above said rotating magnetic surface by said liquid film when writing data to or reading data from said rotating magnetic data surface, wherein said recirculating means includes;

a reservoir in a lower portion of said head-disk enclosure,

a hub assembly rotatably supporting said rotating storage media,

a spiral channel formed in said hub assembly and extending from said reservoir for inducing an upward flow of lubricant from said reservoir through said channel, and

means for distributing liquid lubricant from said spiral channel to the surface of said rotating storage media.

2. The rotating magnetic memory device of claim 1 wherein said storage medium is a rigid magnetic disk.

3. The rotating magnetic memory device of claim 1 wherein said recirculating means comprises means for recirculating said liquid lubricant over said data surface.

4. The rotating magnetic memory device of claim 3 wherein said liquid lubricant is a low viscosity lubricant maintained as a substantially uniform thickness not exceeding 5 microns.

5. The rotating magnetic memory device of claim 1 wherein said enclosure means hermetically seals said rotating storage medium and said magnetic transducer from the surrounding ambient atmosphere.

6. The rotating magnetic memory device of claim 1 wherein said magnetic transducer comprises a slider with a lower surface adapted to confront the rotating data surface from which extend forward and rearward depending feet terminating in bearing surfaces, the transducing gap being positioned at the rearward surface of said slider and a rearward foot.

7. The rotating magnetic memory device of claim 6 wherein aid slider has a triangular front foot and a spaced pair of triangular rear feet.

8. The rotating magnetic memory device of claim 7 wherein said bearing surfaces of said feet are each bounded by a first edge in the direction of the disk inner diameter parallel to the axis of said slider and a second edge toward the disk outer diameter that diverges from said first edge.

9. The rotating magnetic memory device of claim 8 wherein the bearing surfaces of said feet in operation maintain a pressure less than 1000 pounds per square inch.