Hitachi, Ltd.

Mitsuo Mashiko

Katuo Sugawara

Toru Koyama

Syoichi Maruyama

Kenji Mishima

Shinichi Yamashiro

Electrically insulated coils having excellent moisture resistance or water resistance utilize a simple material that is readily available. Using a simple method of manufacture, rotating electric machines such as motors for driving pumps, traction motors for rolling stocks and the like suitable for use in the outdoors may be built with the electrically insulated coils. The coils are coated with a fluorine-containing coating at least on portions which are exposed out of the side of the core. Since a uniform hydrophobic layer utilizing the repellent action of fluorine atoms is capable of being provided on the surface of the electrically insulated coils, the electrically insulated coils and the rotating electrical machines incorporating them feature excellent moisture resistance and water resistance.

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Hitachi, Japan

Mitsuo Mashiko