Abstract: An electrically insulating supporting structure for a high voltage electric apparatus having a high voltage charging part and a ground potential part, the structure being adapted to be disposed between the high voltage charging part apparatus and the ground potential part. The structure includes an organic insulating structure formed in a predetermined shape, and an inorganic insulating layer formed on a surface of the organic insulating structure and an intermediate layer consisting essentially of an organic and an inorganic powder.

Abstract: To provide a Cu-Cr alloy electrode material, a mixture of Cu and cr materials at a predetermined ratio is heated until the mixture has been entirely melted, and the molten metal obtained is quenched to precipitate fine Cr particles in a Cu base. Since Cr is melted into Cu before quenching, and then Cr precipitates, Cr particles finer than those in the sintering or infiltration method can disperse in a Cu base. This invention prevents defects such as voids in the structure and the weakening of the fusion of Cu and Cr or failure of Cr to precipitate into the Cu base caused by oxide films on the surface of the Cr particles, thereby providing a fine alloy structure.

Abstract: Interrupting and chopping characteristics of a Cu--Cr contact alloy are improved by rounding Cr particles to be spherical in the alloy. The Cr particles are rounded in the alloy by sintering raw Cr powder particles having an average particle diameter of less than 100 .mu.m at a temperature of 1,100.degree. C. or higher with Cu powder, or by sintering raw Cr powder particles having an average particle diameter of 100 to 150 .mu.m at a temperature of 1,200.degree. C. or higher with Cu powder.

Abstract: A movable electrical contactor having a surface thereof in slidable contact with a mating conductor, the surface being coated with a composite material in which particles of graphite (C) are dispersed in a matrix of silver (Ag). The coating film is formed by electric plating using a plating liquid of metal silver in the range of 2-100 g/l in concentration, potassium cyanide in the range of 2-250 g/l, potassium hydroxide in the range of 0.5-15 g/l, graphite powder in the range of 1-55 g/l, and a dispersant for dispersing graphite powder into plating liquid in the range of 10-2000 ppm.

Abstract: An electric contact with a base metal used as a switch wherein the non-welded peripheral portion of the contact is prevented from bow-like bending and from peeling off. The electric contact with a base metal having a contact promoting shape is formed by die forging of a contact material joined to the base metal by resistance welding. The composite contact material is prepared by coating the core material of Ag-oxide contact material with non-oxide contact material. The side of the material in contact with the base metal is of non-oxide contact material. The contact material may be pressed to fill a groove preformed in the base metal, welded to protrusions preformed in the base metal, welded to the bottom of a cut preformed in the base metal, or welded to bottoms of recesses preformed in the base metal.

Abstract: A circuit breaker in which a movable contactor is held by a holder of electrically insulating material which is rotatably supported through a switching shaft on a casing. The movable contactor is driven by a switching mechanism to be swung about the switching shaft together with the holder to perform a switching operation. The movable contactor is slidably electrically connected to a connecting conductor secured to the casing.

Abstract: This invention relates to a silver/metal oxide material for electrical contacts containing no Cd which essentially consists of Ag and 5 to 30% by weight of at least one of oxides of Sb, Sn, Zn, In, Cu, Mn, Bi and Pb, and further, if necessary, 0.05 to 2% by weight of at least one of oxides of Mg, Al, Fe, Ni, Co, Si, Ga, Ge, Te, Ca and Li, the total amount of said metal oxides being 5 to 32% by weight, wherein fine particles of said metal oxides are substantially uniformly distributed in a matrix whose main component is Ag in a sintered state, and wherein there are no grain boundaries formed by agglomerations or agglomerated layers of said metal oxides.