Small diameter low watt density immersion heating element
US6744978B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 2001 |
| Grant date | Jun 1, 2004 |
| Priority date | — |
| Expiry date | Dec 26, 2021 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF24H1/102
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention provides immersion heating elements, water heaters and methods for their fabrication and use. In the first embodiment of this invention, a resistance heating element is provided which includes a resistance heating material and an electrically insulating, substantially water impervious sheath disposed over the resistance heating material to form an active element portion having an envelope of about 50 in3, a total wattage of at least 1000 W, and a watt density of no greater than 60 W/in2. Such an element has been demonstrated to substantially reduce scale reduction in water containing calcium, calcium carbonate, or both in solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.