Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Mitsubishi Paper Mills Limited

Hidenori Kawakami

Masahiro Amano

Shunji Seino

Ryota Nishiyama

Keiji Tsuruta

Yoshihiro Ohta

Yutaka Gamou

An aqueous slurry comprising fibrous particles of a heat-resistant aromatic polymer and short fibers made of said polymer or insulating inorganic short fibers, or a mixture thereof, is made into a wet web and, after adjusting the water content to 50 to 95 weight %, said wet web is laid up in a desired number of layers, and then the laminate is dewatered and dried for integration under pressure at a temperature not exceeding the softening point of said aromatic polymer, thereby obtaining an oil-impregnatable insulating board with high strength and capable of uniform impregnation of oil therein.

Oil-impregnatable insulating board

An iron core including two outer legs and a central leg connected at each end to a different one of the outer legs through a yoke. Each of the outer legs includes a stack of trapezoid laminations connected to a stack of trapezoid laminations of the yoke alternating its trapezium laminations through angle butt joints arranged stepwise with equal incremental intervals, the yoke laminations being longer than one another by equal increments equal to that intervals. The central leg includes a stack of parallelogramic laminations alternating those inverted widthwise from the same and connected in lapped relationships to the yoke laminations.

Iron core for three-phase electromagnetic induction machine

Growing community of inventors

Amagasaki, Japan

Hidenori Kawakami