Resistance element for wound-type variable resistors and method of making same
US4719693A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 1985 |
| Grant date | Jan 19, 1988 |
| Priority date | — |
| Expiry date | Dec 5, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49096
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A resistance element causing less sliding noise for use in wound-type variable resistors and a method of making the same are disclosed. A resistance element obtained by winding a metallic resistance wire on a core is subjected to etching treatment. With this etching treatment, the metallic oxides, chlorides and sulfides considered acting as insulators, and organic molecules, adsorbed gases and other contamination forming the surface layer of the resistance wire are dissolved and removed. Furthermore, by immersing the etched resistance element in an ammonia solution, etc., the copper precipitated on the surface of the resistance wire is dissolved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.