Patent US4384311A successfully refreshed from Google Patents.
US4384311A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for cleaning the disc surface and the head support structure in a magnetic disc drive
Assignee: DMA Systems Corp
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Filing: 1981-10-13
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Granted: 1983-05-17
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Expires: 2001-10-13
Abstract
Abstract In a magnetic disc drive, there is disclosed a method for cleaning the magnetic disc surfaces and the heads. The heads are loaded and caused to fly on the disc surfaces. The spindle motor speed is reduced to a speed where the heads fly at approximately 50% of the normal flying height and the head support structure drive motor is commanded to sweep the heads across the disc surfaces, forward and reverse, for several cycles, to remove any particles down to an elevation that is 50% of the normal flying height. The heads are then positioned over unused tracks on the disc surfaces and the spindle motor speed is reduced to a speed where the heads fly at approximately 25% of the normal flying height so as to scrub off any particles left on the heads. The spindle motor speed is then returned to normal speed and a 25% margin of interference-free operation has been assured.
Inventors
- 👤 Michael McNeil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:12
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/50; G11B23/505; G11B5/00; G11B5/41
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
173 words
In a disc drive including a disc having a magnetic surface and supported for rotation on a spindle, a spindle motor for driving said spindle, a transducer head, a head support structure, a drive motor coupled to said head support structure for moving said head along said disc surface, and control means for controlling said drive motor and the speed of said spindle motor, a method for cleaning said disc surface and said head comprising the steps of: loading and flying said head on said disc surface; reducing said spindle motor speed to a speed where said head flies at a first predetermined percentage of the normal flying height; moving said head across said disc surface; positioning said head at a predetermined location on said disc surface; reducing said spindle motor speed to a speed where said head flies at a second predetermined percentage, lower than said first predetermined percentage, of said normal flying height; and increasing said spindle motor speed to a speed where said head flies at said normal flying height.
Claim 2
Dependent Claim
173 words
In a disc drive including a disc having a magnetic surface and supported for rotation on a spindle, a spindle motor for driving said spindle, a transducer head, a head support structure, a drive motor coupled to said head support structure for moving said head along said disc surface, and control means for controlling said drive motor and the speed of said spindle motor, a method for cleaning said disc surface and said head comprising the steps of: loading and flying said head on said disc surface; reducing said spindle motor speed to a speed where said head flies at a first predetermined percentage of the normal flying height; moving said head across said disc surface; positioning said head at a predetermined location on said disc surface; reducing said spindle motor speed to a speed where said head flies at a second predetermined percentage, lower than said first predetermined percentage, of said normal flying height; and increasing said spindle motor speed to a speed where said head flies at said normal flying height.
Claim 3
Dependent Claim
18 words
In a disc drive according to claim 1, a method wherein said first predetermined percentage is approximately 50%.
Claim 4
Dependent Claim
20 words
In a disc drive according to claim 1 or 2, a method wherein said second predetermined percentage is approximately 25%.
Claim 5
Dependent Claim
34 words
In a disc drive according to claim 1, a method wherein said step of moving said head comprises the step of: moving said head back and forth across said disc surface for several cycles.
Claim 6
Dependent Claim
24 words
In a disc drive according to claim 1 or 4, a method wherein said predetermined location is an unused track on said disc surface.
Claim 7
Dependent Claim
136 words
In a disc drive including a disc having a magnetic surface and supported for rotation on a spindle, a spindle motor for driving said spindle, a transducer head, a head support structure, a drive motor coupled to said head support structure for moving said head along said disc surface, and control means for controlling said drive motor and the speed of said spindle motor, a method for cleaning said disc surface and said head comprising the steps of: loading and flying said head on said disc surface; reducing said spindle motor speed to a speed where said head flies at a predetermined percentage of the normal flying height; moving said head back and forth across said disc surface; and increasing said spindle motor speed to a speed where said head flies at said normal flying height.
Claim 8
Dependent Claim
136 words
In a disc drive including a disc having a magnetic surface and supported for rotation on a spindle, a spindle motor for driving said spindle, a transducer head, a head support structure, a drive motor coupled to said head support structure for moving said head along said disc surface, and control means for controlling said drive motor and the speed of said spindle motor, a method for cleaning said disc surface and said head comprising the steps of: loading and flying said head on said disc surface; reducing said spindle motor speed to a speed where said head flies at a predetermined percentage of the normal flying height; moving said head back and forth across said disc surface; and increasing said spindle motor speed to a speed where said head flies at said normal flying height.
Claim 9
Dependent Claim
17 words
In a disc drive according to claim 6, a method wherein said predetermined percentage is approximately 50%.
Claim 10
Dependent Claim
46 words
In a disc drive according to claim 6 or 7, a method further comprising the step of: reducing said spindle motor speed to a speed where said head flies at a second predetermined percentage, lower than said first mentioned predetermined percentage, of said normal flying height.
Claim 11
Dependent Claim
52 words
In a disc drive according to claim 8, a method wherein said step of reducing said spindle motor speed to a speed where said head flies at a second predetermined percentage of said normal flying height is performed after the step of moving said head back and forth across said disc surface.
Claim 12
Dependent Claim
18 words
In a disc drive according to claim 9, a method wherein said second predetermined percentage is approximately 25%.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-05-16 | 1986-11-15 | 1987-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-16 | 1990-11-15 | 1991-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-16 | 1994-11-15 | 1995-05-17 | $7700.00 | Window Closed / Lapsed |