US4487671A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods and apparatus for the electrical machining of a workpiece
Assignee: NATIONAL RESEARCH EVELOPMENT Corp
•
Filing: 1982-04-13
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Granted: 1984-12-11
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Expires: 2002-04-13
Abstract
Abstract In combining electrical discharge machining (EDM) and electrochemical machining (ECM) the use of a strong electrolyte has, in the invention, been found possible. In one embodiment a pulse generator applies an intermittent voltage between an electrode and a workpiece causing both EDM and ECM to take place when a strong electrolyte is interposed in the gap between the electrode and the workpiece. At the onset of arcing a discharge monitor removes the voltage. A wire-cutting machine and method combining EDM and ECM are also described.
Inventors
- 👤 Joseph A. McGeough
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:24
CPC Classifications
B; B23; B23H; B23H5/00; B23H5/02; B23H7/00; B23H7/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
126 words
A method of removing material from a workpiece including positioning the workpiece in a container, just covering the workpiece with an electrolyte, adding a layer of dielectric liquid which floats on, and does not significantly mix with the electrolyte, moving an electrode towards the workpiece until the electrode is in the immediate region of the interface between the electrolyte and the dielectric liquid, and applying an intermittent unidirectional voltage between the electrode and the workpiece in a sense which causes material to be removed from the workpiece by electrolytic action, the dimensions of the gap between the electrode and the workpiece and the applied voltage being such that a current-carrying discharge takes place between the electrode and the workpiece at times while the voltage is applied.
Claim 2
Independent Claim
126 words
A method of removing material from a workpiece including positioning the workpiece in a container, just covering the workpiece with an electrolyte, adding a layer of dielectric liquid which floats on, and does not significantly mix with the electrolyte, moving an electrode towards the workpiece until the electrode is in the immediate region of the interface between the electrolyte and the dielectric liquid, and applying an intermittent unidirectional voltage between the electrode and the workpiece in a sense which causes material to be removed from the workpiece by electrolytic action, the dimensions of the gap between the electrode and the workpiece and the applied voltage being such that a current-carrying discharge takes place between the electrode and the workpiece at times while the voltage is applied.
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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) | 1987-12-11 | 1988-06-11 | 1988-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-11 | 1992-06-11 | 1992-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-11 | 1996-06-11 | 1996-12-11 | $7700.00 | Window Closed / Lapsed |