Patent US3745296A successfully refreshed from Google Patents.
US3745296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Copper tool material for electrical discharge machining
Assignee: Chase Brass and Copper Co Inc
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Filing: 1971-08-20
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Granted: 1973-07-10
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Expires: 1991-08-20
Abstract
Abstract A new electrode material for electrical discharge machining consisting essentially of copper containing a critical oxygen content is disclosed. The novel electrode shows an increase in wear resistance of up to 30 percent over presently known electrode materials and after heat treatment shows an increase of cutting speed three-fold over oxygen free copper electrodes.
Inventors
- 👤 G Shinopulos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:56
CPC Classifications
B; B23; B23H; B23H1/00; B23H1/04; B23H1/06
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
34 words
The electrical discharge machining tool of claim 1 wherein said tool has been heat treated in a reducing atmosphere at a temperature and time sufficient to reduce any copper oxide present in said tool.
Claim 2
Dependent Claim
25 words
The electrical discharge machining tool of claim 2 wherein the heat treatment was at about 500* C for from about 22 to about 90 hours.
Claim 3
Dependent Claim
90 words
An electrical discharge machining electrode consisting of at least 1000 parts per million oxygen up to about 400 parts per million oxygen, said oxygen being chemically combined as copper oxide uniformly dispersed in said electrical discharge machining tool and the balance essentially copper, said electrode being made by a process comprising the steps of introducing oxygen into molten copper in a quantity such that said electrode contains from about 1,000 to about 4,000 parts per million oxygen, casting the said electrode, and shaping said cast electrode to the desired configuration.
Claim 4
Dependent Claim
18 words
The electrode of claim 4 wherein the oxygen is introduced into the molten copper as copper oxide powder.
Claim 5
Dependent Claim
32 words
The electrode of claim 4 including the step of heat treating said electrode in a reducing atmosphere at a temperature of about 500* C for from about 22 to about 90 hours.
Claim 6
Dependent Claim
47 words
In an apparatus for electrical discharge machining, an electrode of improved cutting rate and wear performance consisting essentially of copper containing from about 1,000 to about 4,000 parts per million oxygen, said oxygen being chemically combined as copper oxide uniformly dispersed in said electrical discharge machining tool.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |