Hitachi, Ltd.

Tsuguo Kobayashi

Hitoshi Yokono

Noriyuki Kinjo

Junichi Katagiri

Akio Nishikawa

Tamotsu Ikeda

Masatsugu Ogata

Tetsuo Ishikawa

Kenichi Hironaka

Hideo Umetsu

In a dynamoelectric machine having a stator assembly of coil windings and a core, a heat-dissipating, uninflammable, electro-insulative housing encapsulates the coil windings and the core. The housing is made of a cured molded article or material formed of a resin-filler composition which comprises a liquid unsaturated polyester resin, a finely divided calcium carbonate powder, an inorganic mineral particulate having a particle size larger than that of the calcium carbonate powder, a chopped glass fiber and an aluminum hydroxide powder, wherein the ratio by weight of the calcium carbonate to the mineral particulate is 0.3 to 4, the ratio of the weight of glass fiber to the total weight of the composition is 0.05 to 0.25, the ratio of the weight of the polyester resin to the total weight of the composition is 0.1 to 0.4, the weight ratio of the calcium carbonate powder, the mineral particulate and the glass fiber to the total weight of the composition is 0.15 to 0.80, and the weight ratio of the aluminum hydroxide powder to the total weight of the composition is 0.1 to 0.6.

Uninflammable dynamoelectric machine having coil windings and core

An unsaturated polyester resin composition for use in pressure molding, which comprises an unsaturated polyester resin and fillers consisting essentially of (a) calcium carbonate powder which passes a 325 mesh sieve, (b) an inorganic mineral particulate which passes a 12 mesh sieve and is retained on a 200 mesh sieve and (c) glass fibers having a length larger than 0.2 mm, wherein the ratio by weight of (a) to (b) is within a range of from 0.3 to 10, the ratio of (a)+(b) to the unsaturated polyester resin is within a range of from 1.5 to 7, and the ratio of (c) to the total weight of the resin, calcium carbonate, silica sand and glass fiber is within a range of from 0.01 to 0.25.

Unsaturated polyester resin composition for use in pressure molding

In a dynamoelectric machine having a stator assembly of coil windings and a core, a heat-dissipating, electro-insulative housing encapsulates the coil windings and the core. The housing is made of a cured molded article or material formed of a resin-filler composition which comprises a liquid unsaturated polyester resin, a finely divided calcium carbonate powder, an inorganic mineral particulate having a particle size larger than that of the calcium carbonate powder, and a chopped glass fiber, wherein the ratio by weight of the calcium carbonate to the mineral particulate is 0.3 to 4, the ratio of the weight of glass fiber to the total weight of the composition is 0.05 to 0.25, the ratio of the weight of the polyester resin to the total weight of the composition is 0.1 to 0.4 and the weight ratio of the calcium carbonate powder, the mineral particulate and the glass fiber to the total weight of the composition is 0.6 to 0.9. The disclosure is also concerned with a dynamoelectric machine having a housing made of a cured article of a composition containing a certain amount of clay powder as a separation inhibitor.

Dynamoelectric machine having coil windings and core encapsulated with

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Mito, Japan

Tsuguo Kobayashi