US4243395A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for precision grinding of hard, pointed materials
Assignee: RCA Corp
•
Filing: 1979-06-13
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Granted: 1981-01-06
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Expires: 1999-06-13
Abstract
Abstract A method of lapping the sharp point of a hard material using a silicon oxide, glow discharge deposited abrasive layer wherein the abrasive layer is thick enough to prevent penetration of the point into the substrate.
Inventors
- 👤 Anil R. Dholakia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:01
CPC Classifications
B; B24; B24D; B24D18/00; B24B; B24B19/00; B24B19/16; B24B19/165
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
87 words
In a method of lapping the tip of a hard material having a sharp point to provide a flattened tip of a predetermined length comprising the steps of rotating a substrate having an abrasive layer of amorphous SiO x thereon, said abrasive layer formed by a glow discharge of a silicon compound, and contacting the abrasive layer and the tip, the improvement which comprises using an abrasive layer that is thick enough such that the tip can not penetrate through the abrasive layer to the underlying substrate.
Claim 2
Dependent Claim
87 words
In a method of lapping the tip of a hard material having a sharp point to provide a flattened tip of a predetermined length comprising the steps of rotating a substrate having an abrasive layer of amorphous SiO x thereon, said abrasive layer formed by a glow discharge of a silicon compound, and contacting the abrasive layer and the tip, the improvement which comprises using an abrasive layer that is thick enough such that the tip can not penetrate through the abrasive layer to the underlying substrate.
Claim 3
Dependent Claim
10 words
The method of claim 1 wherein the substrate is vinyl.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein the substrate is metal-coated vinyl.
Claim 5
Dependent Claim
18 words
The method of claim 1 wherein the thickness of the abrasive layer is at least about 2000 angstroms.
Claim 6
Dependent Claim
11 words
The method of claim 1 wherein the hard material is diamond.
Claim 7
Dependent Claim
11 words
The method of claim 1 wherein the hard material is sapphire.
Claim 8
Dependent Claim
16 words
The method of claim 1 wherein the point is less than about 0.1 micrometer in diameter.
References Cited (Backward Citations)
US2899288A
Cited
US4104832A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-06 | 1984-07-07 | 1985-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-06 | 1988-07-07 | 1989-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-06 | 1992-07-07 | 1993-01-06 | $7700.00 | Window Closed / Lapsed |