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US4497699A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of treating foil for electrolytic capacitors

Assignee: US Philips Corp
•
Filing: 1983-03-28
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Granted: 1985-02-05
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Expires: 2003-03-28
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Abstract

Abstract A method of treating foil for use in electrolytic capacitors in which the foil moves in one direction through a treatment liquid and in which the capacitance is measured continuously by means of at least one current-carrying electrode from which alternating current is conveyed and at least one voltage electrode at a small distance from the foil. The foil capacitance is measured by means of a phase-sensitive voltmeter. The measured capacitance is used to control the treatment method, etching or forming. In a preferred embodiment two current-carrying electrodes are present on either side of the foil and two voltage electrodes are present between the current-carrying electrodes and the foil on either side thereof. This avoids contacting of the foil.

Inventors

  • 👤 Hendrik J. De Wit
  • 👤 Albertus W. M. Van Berlo
  • 👤 Cornelis Crevecoeur

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 05:25
CPC Classifications
H; H01; H01G; H01G9/00; H01G9/004; H01G9/04; H01G9/048; H01G9/055

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 119 words
A method for treating foil for use in electrolytic capacitors in which said foil moving in one direction is passed through a treatment liquid and in the liquid the capacitance of the foil is measured continuously, including the steps of: passing an alternating current from at least one current-carrying electrode immersed in the treatment liquid in the proximity of the foil in the treatment liquid; and having present at least one voltage electrode at a small distance from the foil between the current-carrying electrode(s) and the foil at which voltage electrode the voltage is measured as a measure of the required foil capacitance by means of a phase-sensitive voltmeter; and using the measured capacitance to control the treatment process.
Claim 2
Independent Claim 119 words
A method for treating foil for use in electrolytic capacitors in which said foil moving in one direction is passed through a treatment liquid and in the liquid the capacitance of the foil is measured continuously, including the steps of: passing an alternating current from at least one current-carrying electrode immersed in the treatment liquid in the proximity of the foil in the treatment liquid; and having present at least one voltage electrode at a small distance from the foil between the current-carrying electrode(s) and the foil at which voltage electrode the voltage is measured as a measure of the required foil capacitance by means of a phase-sensitive voltmeter; and using the measured capacitance to control the treatment process.
Claim 3
Dependent Claim 45 words
A method as claimed in claim 1, further including the steps of: having two current-carrying electrodes present, one on each side of the foil; and measuring the imaginary part or the impedance as a measure of the foil capacitance by means of two voltage electrodes.

References Cited (Backward Citations)

US2832734A Cited
US2928774A Cited
US4095176A Cited
US4129480A Cited
US4455200A Cited
US4343686A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-02-05 1988-08-06 1989-02-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-02-05 1992-08-06 1993-02-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-02-05 1996-08-06 1997-02-05 $7700.00 Window Closed / Lapsed

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