Patent US4477040A successfully refreshed from Google Patents.
Patent US3202599A successfully refreshed from Google Patents.
US3202599A
Expired / Lapsed
US
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Direct current source for electrolytic metal machining with zener diode surge protection
Assignee: Deutsche Edelstahlwerke AG
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Filing: 1961-09-05
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Granted: 1965-08-24
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Expires: 1981-09-05
Abstract
No abstract record available.
Inventors
- 👤 Schierholt Hans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:10
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/04; G05F3/06; B; B23; B23H; B23H3/00; B23H3/02; G05F1/00; G05F1/10; G05F1/12; G05F1/32
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
146 words
IN AN ELECTRO-EROSION MACHINING APPARATUS AN ELECTRIC OPERATING CIRCUIT COMPRISING A DIRECT CURRENT SOURCE, A TOOL ELECTRODE CONNECTED TO SAID SOURCE, A WORKPIECE ELECTRODE CONNECTED TO SAID SOURCE, AND A WORKING GAP IN SAID CIRCUIT BETWEEN SAID TOOL ELECTRODE AND SAID WORKPIECE ELECTRODE, SAID GAP BEING FILLED WITH AN ELECTROLYTE, A NON-LINEAR RESISTOR CONNECTED ACROSS SAID WORKING GAP, SAID NON-LINEAR RESISTOR COMPRISING A ZENER DIODE HAVING A BREAKDOWN VOLTAGE WHICH IS LOWER THAN THE CIRTICAL ARCING OR SPARKLING VOLTAGE ACROSS THE WORKING GAP BETWEEN SAID TOOL AND WORKPIECE LECTRODES, A BRIDGING ARRANGEMENT ACROSS SAID ZENER DIODE, SAID BRIDGING ARRANGEMENT COMPRISING A SERIES COMBINATION OF A RESISTOR AND A CONDENSER IN PARALLEL WITH SAID ZENER DIODE, AND A REGULATOR COUPLED TO SAID CIRCUIT, SAID REGULATOR RESPONDING TO THE RATE OF CHANGE OF THE WORKING CURRENT IN SAID CIRCUIT TO REGULATE THE VOLTAGE OF SAID DIRECT CURRENT SOURCE.
Claim 2
Dependent Claim
146 words
IN AN ELECTRO-EROSION MACHINING APPARATUS AN ELECTRIC OPERATING CIRCUIT COMPRISING A DIRECT CURRENT SOURCE, A TOOL ELECTRODE CONNECTED TO SAID SOURCE, A WORKPIECE ELECTRODE CONNECTED TO SAID SOURCE, AND A WORKING GAP IN SAID CIRCUIT BETWEEN SAID TOOL ELECTRODE AND SAID WORKPIECE ELECTRODE, SAID GAP BEING FILLED WITH AN ELECTROLYTE, A NON-LINEAR RESISTOR CONNECTED ACROSS SAID WORKING GAP, SAID NON-LINEAR RESISTOR COMPRISING A ZENER DIODE HAVING A BREAKDOWN VOLTAGE WHICH IS LOWER THAN THE CIRTICAL ARCING OR SPARKLING VOLTAGE ACROSS THE WORKING GAP BETWEEN SAID TOOL AND WORKPIECE LECTRODES, A BRIDGING ARRANGEMENT ACROSS SAID ZENER DIODE, SAID BRIDGING ARRANGEMENT COMPRISING A SERIES COMBINATION OF A RESISTOR AND A CONDENSER IN PARALLEL WITH SAID ZENER DIODE, AND A REGULATOR COUPLED TO SAID CIRCUIT, SAID REGULATOR RESPONDING TO THE RATE OF CHANGE OF THE WORKING CURRENT IN SAID CIRCUIT TO REGULATE THE VOLTAGE OF SAID DIRECT CURRENT SOURCE.
References Cited (Backward Citations)
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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) | 1968-08-23 | 1969-02-22 | 1969-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-08-23 | 1973-02-22 | 1973-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-08-23 | 1977-02-22 | 1977-08-24 | $7700.00 | Window Closed / Lapsed |