Electrical heating cable with temperature self-limiting heating elements
US4072848A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1976 |
| Grant date | Feb 7, 1978 |
| Priority date | — |
| Expiry date | Aug 16, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B3/56
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrical heating cable which limits power output once an established temperature limit is reached. The cable includes heating elements in the form of temperature-sensitive variable resistance elements electrically connected in parallel between two supply bases at spaced positions along the length of the buses. The heating elements not only serve to generate heat for heating but also undergo a substantial positive increase in resistivity when the temperature of the cable nears the established temperature limit. The increase in resistivity substantially reduces the heat-generating current in the cable to limit the power output to within established heat limits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.