Method for controlling etching of electrolytic capacitor foil
US4343686A · kind A · utility
4Cited by
10References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1981 |
| Grant date | Aug 10, 1982 |
| Priority date | — |
| Expiry date | Feb 27, 2001 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25F3/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a process for etching aluminum foil to increase its actual surface area to apparent surface area for use as an electrode in an electrolytic capacitor, a wire coil is placed adjacent the foil as it exits the etch station. The coil is energized to produce eddy currents in the foil. The voltage induced by theses eddy currents is sensed at the same coil or another coil. The foil drawing speed through the etch station is altered in response to that sensed voltage, or another process parameter is changed, to maintain at a constant value the ratio of the actual to apparent foil surface area.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.