Abstract: When a trigger discharge between a metal cathode and a trigger ring induces a vacuum-arc discharge between the cathode an anode, which vaporizes the substances of the cathode surface to produce a metal ion plasma, setting the pulse length of the arc pulse applied between the cathode and the anode to 1 msec or longer will soon short-circuit between the cathode and the trigger ring due to the vaporized substances deposited on the surface of the insulating ring. In order to solve this problem, a permanent magnet 36 for forming a magnetic field across a space between the anode 26 and the cathode 34 is provided close to the rear side of the trigger ring 35 so as to guide the substances vaporized from the cathode 34 toward the anode 26. Thereby, a longer continuous operation can be done with setting the arc pulse longer.

Abstract: In an apparatus in which a vacuum-arc discharge is generated between a metal cathode and anode plate and an evaporated substance from the cathode is supplied through openings on the anode plate, conventionally, a cleaning work to remove metal films deposited on the edges of the openings has to be done periodically, which limits continuous operation. The apparatus relating to the invention is provided with a rotary anode plate 14 on which a plurality of openings 17 are formed on a circumference concentric with the rotary axis of the anode plate. As the anode plate 14 rotates, the openings 17 are designed to come into a position to face the cathode. This construction can continue a longer operation with an extremely low deterioration of the performance without a maintenance work requiring a relief of the vacuum.

Abstract: An apparatus for separating and sorting non-ferrous metals from other materials is provided which has a ferromagnetic core, an infeed conveyor for positioning materials to be separated and sorted, and a collecting bin or container located at a selected distance from the infeed conveyor for collecting separated and sorted non-ferrous metals, and which produces an electromagnetic field which provides a non-steady state, non-uniform magnetic field, and a sharp skin effect in the non-ferrous metal piece. Also provided is a method for separating and sorting non-ferrous metal pieces from other materials wherein non-ferrous metal pieces are subjected to a non-steady state, non-uniform magnetic field so that a sharp skin effect is produced in the non-ferrous metal piece so that the non-ferrous metal piece is separated and sorted according to its density and independent of its conductivity.