US4244318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin particulate film spin coater
Assignee: Unisys Corp
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Filing: 1979-12-31
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Granted: 1981-01-13
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Expires: 1999-12-31
Abstract
Abstract A device for spincoating an ultra-thin iron powder film on a disk for magnetic recording. Ultra-thin films are utilized on magnetic disks in view of a high density recording that may be achieved on such devices. The invention develops an iron powder particulate composition which is pre-sheared to a particular consistency within a spin chamber which is compartmented by perforated vanes, disposed on a common axis with and above the magnetic disk, and is selectively coupled to the drive shaft of the disk spinner. Magnetic means are actuable to raise the bell-type cover of the spin chamber whereby to discharge coating material onto the spinning disk. Means decouple the chamber from the drive shaft and vary the spin rate of said shaft to effect the desired thinness of coating.
Inventors
- 👤 T. F. Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:12
CPC Classifications
B; B05; B05C; B05C5/00; B05C11/00; B05C11/02; B05C11/08; G; G11; G11B; G11B5/00; G11B5/84; G11B5/842
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
152 words
A thin film particulate spin coater apparatus comprising: (a) a metallic disk means having a hole located at its center; (b) a mixing chamber which is adapted to be positioned over said disk hole; (c) means for introducing a thixotropic composition into said chamber, said composition comprising iron powder, a resin and solvent; (d) means for rotating said disk and said mixing chamber at a first speed until said composition is in a Newtonian state; (e) means for releasing said Newtonian composition onto said rotating disk so that its surface is flooded therewith; and (f) means for decoupling the rotation of said mixing chamber and the rotation of said disk and thereafter rotating said disk at a second higher speed; and (g) means for controlling the evaporation of said solvent while said disk is spinning at said first and second higher speeds whereby an ultra-thin surface is formed upon said disk surface.
Claim 2
Dependent Claim
152 words
A thin film particulate spin coater apparatus comprising: (a) a metallic disk means having a hole located at its center; (b) a mixing chamber which is adapted to be positioned over said disk hole; (c) means for introducing a thixotropic composition into said chamber, said composition comprising iron powder, a resin and solvent; (d) means for rotating said disk and said mixing chamber at a first speed until said composition is in a Newtonian state; (e) means for releasing said Newtonian composition onto said rotating disk so that its surface is flooded therewith; and (f) means for decoupling the rotation of said mixing chamber and the rotation of said disk and thereafter rotating said disk at a second higher speed; and (g) means for controlling the evaporation of said solvent while said disk is spinning at said first and second higher speeds whereby an ultra-thin surface is formed upon said disk surface.
Claim 3
Dependent Claim
48 words
The apparatus in accordance with claim 1 wherein said mixing chamber includes: (a) vertically positioned vanes which are separated from one another and arranged circumferentially within said chamber, (b) each said vane having a plurality of perforations for allowing said composition to be forced therethrough by centrifugal force.
Claim 4
Dependent Claim
34 words
The apparatus in accordance with claim 2 wherein said vertically positioned vanes comprise: (a) curved portions located at the vane's highest vertical portion, (b) whereby said composition may more readily reach the Newtonian state.
Claim 5
Dependent Claim
48 words
The apparatus in accordance with claim 1 wherein said means for releasing said Newtonian composition comprises, (a) means for raising a side of said mixing chamber, whereby said composition is released onto said metallic disk in a Newtonian state from a center of said disk to its periphery.
Claim 6
Dependent Claim
31 words
Apparatus in accordance with claim 1 wherein said means for controlling the evaporation of said solvent while said disk is spinning comprises: (a) an adjustable hood means for enclosing said disk.
Claim 7
Dependent Claim
35 words
Apparatus in accordance with claim 5, wherein said hood means includes: (a) a cusp which is circumferentially arranged on its periphery, (b) whereby circulation of solvents and air within said hood may be substantially improved.
Claim 8
Dependent Claim
42 words
The apparatus in accordance with claim 1 wherein (a) said disk is located on a first shaft, and (b) said mixing chamber is located on a second shaft, and (c) wherein said first and second shafts may be separated from one another.
Claim 9
Dependent Claim
45 words
The apparatus in accordance with claim 7 wherein the means for decoupling the rotation of the mixing chamber from the rotation of the disk comprises: (a) lifting means for separating the first and second shaft while retaining the evaporation control means over said rotating disk.
Claim 10
Dependent Claim
22 words
The apparatus in accordance with claim 7 including: (a) means for limiting the height at which said mixing chamber may be lifted.
Claim 11
Dependent Claim
44 words
The apparatus in accordance with claim 8 wherein said lifting means for separating the first and second shaft includes: (a) means for separating the first and second shaft to a height whereby said hood and pre-mix chamber may be entirely removed from said disk.
References Cited (Backward Citations)
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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) | 1984-01-13 | 1984-07-14 | 1985-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-13 | 1988-07-14 | 1989-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-13 | 1992-07-14 | 1993-01-13 | $7700.00 | Window Closed / Lapsed |