Patent US3813637A successfully refreshed from Google Patents.
US4211908A
Expired / Lapsed
US
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Apparatus for high frequency discharge shaping of a workpiece by means of a rectangular bipolar pulsating voltage
Assignee: Mitsubishi Electric Corp
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Filing: 1977-02-07
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Granted: 1980-07-08
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Expires: 1997-02-07
Abstract
Abstract A method and apparatus for electrical discharge machining are disclosed. The method includes the use of a bipolar pulsating voltage to improve the quality of a discharge machining operation. The use of an intermittent AC voltage and an intermittent AC voltage with an intermittent DC voltage interposed during the quiescent periods thereof is also disclosed. A water bath for discharge machining is disclosed, as is a novel circuit for producing bipolar pulsating power and a novel apparatus for combining a plurality of such power supplies and insuring that all output power is maintained in the same phase. Electrode shielding and automatic drive methods and apparatus are disclosed as is a novel capacitive electrode coupling technique.
Inventors
- 👤 Yoshiei Niwa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 03:49
CPC Classifications
B; B23; B23H; B23H1/00; B23H1/02; B23H1/022; B23H2300/00; B23H2300/20; B23H2300/22
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
105 words
In a high frequency discharge shaping apparatus, having an electrode and means for spacedly mounting said electrode and a workpiece to form a discharge gap therebetween, a power supply comprising: a plurality of transformer coil means; a plurality of sources of rectangular bipolar pulsating current signals wherein the magnitude of the maximum positive voltage is substantially equal to the magnitude of the maximum negative voltage coupled to said plurality of transformer coil means; and a power accumulating coil electromagnetically coupled to said plurality of transformer coil means for accumulating the electrical power thereof and for supplying output power of a single phase across said gap.
Claim 2
Dependent Claim
105 words
In a high frequency discharge shaping apparatus, having an electrode and means for spacedly mounting said electrode and a workpiece to form a discharge gap therebetween, a power supply comprising: a plurality of transformer coil means; a plurality of sources of rectangular bipolar pulsating current signals wherein the magnitude of the maximum positive voltage is substantially equal to the magnitude of the maximum negative voltage coupled to said plurality of transformer coil means; and a power accumulating coil electromagnetically coupled to said plurality of transformer coil means for accumulating the electrical power thereof and for supplying output power of a single phase across said gap.
Claim 3
Dependent Claim
112 words
In a high frequency discharge shaping apparatus having an electrode and means for spacedly mounting said electrode and a workpiece to form a discharge gap therebetween, a power supply including a plurality of transformer coil means, a plurality of sources of rectangular bipolar pulsating current signals, said plurality of sources respectively coupled to said plurality of transformer coil means, and a power accumulating coil electromagnetically coupled to said plurality of transformer coil means for accumulating the electrical power thereof and for supplying output power of a single phase; and a coupling ring positioned around but spaced from said electrode and coupled to said power supply for capacitively supplying power to said electrode.
Claim 4
Dependent Claim
112 words
In a high frequency discharge shaping apparatus having an electrode and means for spacedly mounting said electrode and a workpiece to form a discharge gap therebetween, a power supply including a plurality of transformer coil means, a plurality of sources of rectangular bipolar pulsating current signals, said plurality of sources respectively coupled to said plurality of transformer coil means, and a power accumulating coil electromagnetically coupled to said plurality of transformer coil means for accumulating the electrical power thereof and for supplying output power of a single phase; and a coupling ring positioned around but spaced from said electrode and coupled to said power supply for capacitively supplying power to said electrode.
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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) | 1983-07-08 | 1984-01-07 | 1984-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-08 | 1988-01-07 | 1988-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-08 | 1992-01-07 | 1992-07-08 | $7700.00 | Window Closed / Lapsed |