Encased electric motor employing gas as heat dissipating means
US4486677A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 1983 |
| Grant date | Dec 4, 1984 |
| Priority date | — |
| Expiry date | May 2, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K5/128
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In an encased electric motor within a casing, an electrically insulating varnish is applied by vacuum impregnation to the inside surfaces of the casing and to the outer surface of the stator of the motor. The remaining empty space within the casing is filled with a heat conducting gas mixture comprising approximately 60-90% by volume of helium, with the remaining percentage being an electrically insulating gas having better electrically insulating properties than helium, such as sulphur hexafluoride. This encased motor is much lighter than conventional encased motors in which the stator enclosure is filled with a heat conducting resin potting compound and avoids warping damage which frequently occurs in conventional encased motors due to thermal expansion of the heat conducting resin potting compound.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.