The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 04, 1984
Filed:
May. 02, 1983
Sakuei Yamamoto, Fukuoka, JP;
Hiroshi Inao, Fukuoka, JP;
Kiyonori Tokumitsu, Fukuoka, JP;
Mitsuhiro Nishida, Fukuoka, JP;
Takatoshi Ishikawa, Maebaru, JP;
Shigekazu Sakabe, Amagasaki, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
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.