Abstract: A vacuum valve includes a vacuum vessel having an interior portion sealed by a fixed-end end plate and a moving-end end plate disposed at first and second end portions, respectively, of a cylindrical electrically-insulating tube, a fixed electrode rod secured to the fixed-end end plate, a fixed electrode being disposed on an end portion of the fixed electrode rod, a movable electrode rod, a movable electrode capable of contacting and separating from the fixed electrode being disposed on an end portion of the movable electrode rod, and an electrode shield secured to the electrically-insulating tube and enveloping the fixed electrode and the movable electrode, the electrode shield preventing an inner wall surface of the electrically-insulating tube from being polluted by a metallic vapor generated by the fixed electrode and the movable electrode during electric-current interruption, a recess portion being formed in a central portion of only one of either a contact surface of the movable electrode or a contact s

Abstract: A pre-assembled vacuum switch tube having a clearance between a stationary electrode rod and end plate is firstly prepared by forming an enlarged diameter part in the stationary electrode rod at a position where the rod extends from the end plate to the outside of the vacuum envelope and by arranging at least one piece of plate-like brazing material having a flat surface. The pre-assembled vacuum switch tube is put into a vacuum furnace; the interior of the vacuum switch tube is evacuated through the clearance; temperature in the furnace is elevated to melt the brazing material thereby causing the descending of the enlarged diameter part due to the dead weight of the stationary electrode rod and the vacuum switch tube is sealed by bonding of the end plate and the rod.

Abstract: The disclosed electrode composition for a vacuum switch comprises copper, as a principal ingredient, a low melting point metal such as Bi, Pb, In, Li, Sn or any of their alloys, in a content not exceeding 20% by weight, a first additional metal such as Te, Sb, La, Mg or any of their alloys and a refractory metal such as Cr, Fe, Co, Ni, Ti, W or any of their alloys in a content less than 40% by weight.

Abstract: A novel method of producing a contact device for a switch is disclosed. According to the present invention, a powdered contact alloy material is pressed with a substrate on which is placed the contact material. The resulting molded article is sintered for bonding said contact alloy material to said substrate. The resulting sintered product is machined to have the shape of a contact and ultimately an electrode bar is attached by brazing to said substrate.

Abstract: The disclosed electrode composition for a vacuum switch comprises copper, as a principal ingredient, a low melting point metal such as Bi, Pb, In, Li, Sn or any of their alloys, in a content not exceeding 20% by weight, a first additional metal such as Te, Sb, La, Mg or any of their alloys and a refractory metal such as Cr, Fe, Co, Ni, Ti, W or any of their alloys in a content less than 40% by weight.

Abstract: A contact for a vacuum circuit breaker is disclosed which contains copper as a first component and also at least two elements of the group of chromium, molybdenum, and tungsten as the other components. Each of these other components is contained in an amount not greater than 40% by weight.

Abstract: A contactor for a vacuum type circuit interrupter having a pair of detachable electrodes in a vacuum chamber comprises an electrode obtained by melting or sintering a composition of an electric conductive metal of copper or silver as a main component and at least one metal oxide having a melting point lower than that of said conductive metal of bismuth oxide, thallium oxide, indium oxide, antimony oxide or tellurium oxide as an additive, in vacuum or a reduced atmosphere or a nonoxidative atmosphere.