Electric heating tube
US4156127A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1977 |
| Grant date | May 22, 1979 |
| Priority date | — |
| Expiry date | Mar 31, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2836
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A heating tube adapted to electrically heat a fluid carried therethrough includes an inner tubular layer of polytetrafluoroethylene, a second tubular layer surrounding the inner layer and being formed of a homogeneous mixture of polytetrafluoroethylene and electrically conductive carbon, and a third layer surrounding the second layer and being formed of polytetrafluoroethylene. The three layers are coextruded together. The third layer is cut away at at least two circumferential points and the exposed second layer is there provided with a sintered coating for finely divided silver and finely divided polytetrafluoroethylene. The sintered coating is then wrapped with a silicone resin tape containing dispersed silver particles and a metal ring is then fitted over the silicone resin tape thereby forming an electrical terminal for the heating tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.