Patent US4027134A successfully refreshed from Google Patents.
US4027134A
Expired / Lapsed
US
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Electrode for electrical discharge machining
Assignee: Toshiba Corp
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Filing: 1976-09-10
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Granted: 1977-05-31
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Expires: 1996-09-10
Abstract
Abstract An electrode for electrical discharge machining formed of a tungsten-based alloy including Ag and/or Cu, 15 to 40% by weight, and ZrO2, 0.5 to 10% by weight.
Inventors
- 👤 Osamu Arakawa
- 👤 Tadaaki Sekiguchi
- 👤 Eiichi Takayanagi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:45
CPC Classifications
B; B23; B23H; B23H1/00; B23H1/04; B23H1/06
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
41 words
An electrical discharge machining electrode formed of a tungsten-based alloy consisting essentially of 15% to 40% by weight of one member selected from silver, copper or mixtures thereof, 0.5% to 10% by weight of zirconium oxide and the balance of tungsten.
Claim 2
Dependent Claim
41 words
An electrical discharge machining electrode formed of a tungsten-based alloy consisting essentially of 15% to 40% by weight of one member selected from silver, copper or mixtures thereof, 0.5% to 10% by weight of zirconium oxide and the balance of tungsten.
Claim 3
Dependent Claim
29 words
The electrode according to claim 1 wherein the content of said member is 25% to 40% by weight, and that of zirconium oxide is 2% to 8% by weight.
Claim 4
Dependent Claim
29 words
The electrode according to claim 1, wherein the content of said member is 30% to 38% by weight, and that of zirconium oxide is 2% to 6% by weight.
References Cited (Backward Citations)
US2984731A
Cited
US3198932A
Cited
US3413435A
Cited
US3378671A
Cited
US3597649A
Cited
US3585342A
Cited
US3745296A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-30 | 1980-11-29 | 1981-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-30 | 1984-11-29 | 1985-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-30 | 1988-11-29 | 1989-05-31 | $7700.00 | Window Closed / Lapsed |