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US4681997A Expired / Lapsed US ⏱️ 0.0 years remaining

Wire-cut, electric discharge machining power supply unit

Assignee: Fanuc Corp
•
Filing: 1984-10-11
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Granted: 1987-07-21
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Expires: 2004-10-11
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Abstract

Abstract A wire-cut, electric discharge machining power supply unit charges a capacitor (4) by a DC power source (2) via a switching element (1), and discharges the stored charges of the capacitor (4) between a workpiece (6) and a wire electrode (7) via another switching element (5). A single-polarity discharge current of a small pulse width is supplied between the wire electrode (7) and the workpiece (6). A series circuit of an impedance element (50, 80) other than a capacitance and a diode (51), is connected in a backward direction with respect to a capacitor charging voltage to effect recharging of the capacitor (4) with high efficiency.

Inventors

  • 👤 Michiya Inoue
  • 👤 Haruki Obara
  • 👤 Shunzo Izumiya

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 12:26
CPC Classifications
B; B23; B23H; B23H1/00; B23H1/02; B23H1/022; B23H2300/00; B23H2300/20

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 134 words
A wire-cut, electric discharge machining power supply unit for use in machining a workpiece, comprising: a DC power source; a first switching element coupled to said DC power source; a capacitor coupled to said DC power source and said first switching element, said capacitor being charged by said DC power source via said first switching element; a second switching element coupled to said capacitor; a wire electrode coupled to said second switching element and positioned adjacent the workpiece, the stored charges of said capacitor being discharged between the workpiece and said wire electrode via said second switching element; and a series circuit, consisting of a diode and an inductance, connected in parallel to said capacitor, said diode being connected in a backward direction relative to the polarity of the charged voltage of said capacitor.
Claim 2
Dependent Claim 134 words
A wire-cut, electric discharge machining power supply unit for use in machining a workpiece, comprising: a DC power source; a first switching element coupled to said DC power source; a capacitor coupled to said DC power source and said first switching element, said capacitor being charged by said DC power source via said first switching element; a second switching element coupled to said capacitor; a wire electrode coupled to said second switching element and positioned adjacent the workpiece, the stored charges of said capacitor being discharged between the workpiece and said wire electrode via said second switching element; and a series circuit, consisting of a diode and an inductance, connected in parallel to said capacitor, said diode being connected in a backward direction relative to the polarity of the charged voltage of said capacitor.
Claim 3
Dependent Claim 150 words
A wire-cut, electric discharge machining power supply unit for use in machining a workpiece, comprising: a power source; a first switching element coupled to said power source; a capacitor coupled to said power source and said first switching element, said capacitor being charged by said power source via said first switching element; a second switching element coupled to said capacitor; a wire electrode coupled to said second switching element and positioned adjacent the workpiece, the stored charges of said capacitor being discharged between the workpiece and said wire electrode via said second switching element; control means for controlling the switching of said first and second switching elements; and a series circuit connected in parallel with said capacitor, said series circuit consisting of and inductance and a diode connected to said inductance, said diode being connected in a backward direction relative to the polarity of the charged voltage of said capacitor.
Claim 4
Dependent Claim 150 words
A wire-cut, electric discharge machining power supply unit for use in machining a workpiece, comprising: a power source; a first switching element coupled to said power source; a capacitor coupled to said power source and said first switching element, said capacitor being charged by said power source via said first switching element; a second switching element coupled to said capacitor; a wire electrode coupled to said second switching element and positioned adjacent the workpiece, the stored charges of said capacitor being discharged between the workpiece and said wire electrode via said second switching element; control means for controlling the switching of said first and second switching elements; and a series circuit connected in parallel with said capacitor, said series circuit consisting of and inductance and a diode connected to said inductance, said diode being connected in a backward direction relative to the polarity of the charged voltage of said capacitor.
Claim 5
Dependent Claim 23 words
A wire-cut, electric discharge machining power supply unit as set forth in claim 2, wherein said power source comprises a DC power source.
Claim 6
Dependent Claim 23 words
A wire-cut, electric discharge machining power supply unit as set forth in claim 3, wherein said first an second switching elements comprise transistors.
Claim 7
Dependent Claim 23 words
A wire-cut, electric discharge machining power supply unit as set forth in claim 2, wherein said first and second switching elements comprise transistors.

References Cited (Backward Citations)

US2835784A Cited
US3549851A Cited
US3745444A Cited
US4034281A Cited
JPS5385596A Cited
JPS5621728A Cited
SU925496A1 Cited
SU865580A1 Cited
JPS57184629A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-07-20 1991-01-19 1991-07-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-07-20 1995-01-19 1995-07-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-07-20 1999-01-19 1999-07-21 $7700.00 Window Closed / Lapsed

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