Electrically powered immersion heating elements and controls therefor
US5706390A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 26, 1995 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Jan 26, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA47J27/21158
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electric immersion heating element has an elongate, metal-sheathed, electrically insulated, resistance heating portion (1) engaged at its ends in bores formed in an element head (2) which may be formed of a synthetic plastics material, a heat transfer element (8) formed of a high thermal conductivity material extends from a heated part of the resistance heating portion adjacent one of its ends through the element head to enable the element temperature to be sensed from the opposite side of the head, and a tubular enclosure (7) extends from the element head (2) and surrounds the part of the resistance heating portion of the element. The element construction enables dry-boil protection and automatic switch-off on boiling to be achieved by use of a single thermal sensor coupled to the heat transfer element (8) since the steam generated in the enclosure when water boils causes water to be expelled from the enclosure thereby mimicing a dry boil situation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.