Patent US5489474A successfully refreshed from Google Patents.
Patent US4448656A successfully refreshed from Google Patents.
US4448656A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrolytic/electric discharge machining of a non-conductive workpiece
Assignee: Ohyo Jiki Labolatory Co Ltd
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Filing: 1982-06-22
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Granted: 1984-05-15
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Expires: 2002-06-22
Abstract
Abstract The electrolytic/electric discharge machining of a workpiece of a non-conductive hard material, for example, ceramic material is carried out by preparing a grinding wheel having conductive regions and non-conductive abrasive regions circumferentially alternately arranged on the circumferential edge of the wheel, and bringing the rotating grinding wheel in contact with the workpiece while applying AC or DC voltage across the grinding wheel and the non-conductive workpiece.
Inventors
- 👤 Akio Kuromatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:14
CPC Classifications
B; B24; B24B; B24B1/00; B24B1/002; B23; B23H; B23H5/00; B23H5/02; B23H5/10; B24D; B24D5/00; B24D5/06; Y; Y10; Y10S; Y10S204/00; Y10S204/09
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
72 words
A method for the electrolytic/electric discharge machining of a non-conductive workpiece, comprising preparing a grinding wheel having conductive regions and non-conductive abrasive regions circumferentially alternately arranged at least on the circumferential edge of the wheel, placing a non-conductive workpiece beneath the surface of an electrolyte, and bringing the rotating grinding wheel in contact with said non-conductive workpiece while applying voltage between the conductive regions of said grinding wheel and said non-conductive workpiece.
Claim 2
Independent Claim
72 words
A method for the electrolytic/electric discharge machining of a non-conductive workpiece, comprising preparing a grinding wheel having conductive regions and non-conductive abrasive regions circumferentially alternately arranged at least on the circumferential edge of the wheel, placing a non-conductive workpiece beneath the surface of an electrolyte, and bringing the rotating grinding wheel in contact with said non-conductive workpiece while applying voltage between the conductive regions of said grinding wheel and said non-conductive workpiece.
Claim 3
Dependent Claim
13 words
A method according to claim 1 wherein the voltage applied is AC voltage.
Claim 4
Dependent Claim
13 words
A method according to claim 1 wherein the voltage applied is DC voltage.
Claim 5
Dependent Claim
23 words
A method according to claim 1 wherein said non-conductive abrasive regions are composed of a sintered body of abrasive grains in a bond.
Claim 6
Dependent Claim
29 words
A method according to claim 4 wherein said abrasive grain is selected from the group consisting of green carborundum, white alundum, pink alundum, silica, boron nitride, and diamond grains.
Claim 7
Dependent Claim
16 words
A method according to claim 1 wherein said conductive regions are composed of a metallic material.
Claim 8
Dependent Claim
24 words
A method according to claim 6 wherein said metallic material is an alloy of one or more metals selected from silver, copper and nickel.
Claim 9
Dependent Claim
56 words
A method according to claim 1 wherein said grinding wheel comprises a conductive hub, a conductive disc encircling the hub, and an annular bonded abrasive body encircling the disc, wherein metallic strips are embedded in the circumferential edge of said abrasive body to form the conductive regions and electrically connected to the hub through the disc.
Claim 10
Dependent Claim
25 words
A method according to claim 1 wherein said non-conductive workpiece is of a material selected from the group consisting of ceramics, glass, quartz, and sapphire.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-15 | 1987-11-14 | 1988-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-15 | 1991-11-14 | 1992-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-15 | 1995-11-14 | 1996-05-15 | $7700.00 | Window Closed / Lapsed |