Abstract: A device for obtaining multicrystalline silicon, including: at least one crucible made of quartz for the silicon, removably housed in a cup-shaped graphite container; a fluid-tight openable casing; a top induction coil, set facing, with interposition of a graphite plate, the crucible, a lateral induction coil, set around a side wall of the graphite container, and a bottom induction coil, set facing a bottom wall of the graphite container and vertically mobile for varying the distance from the bottom wall; and first means for a.c. electrical supply of the induction coils separately from one another, and second means for supply of a coolant within respective hollow turns of the induction coils; the bottom induction coil includes four spiral windings, arranged alongside one another; electrical switching means enable in use selective connection of the four windings to one another according to different configurations.

Abstract: A device for obtaining multicrystalline silicon, including: at least one crucible, removably housed in a cup-shaped graphite container; a fluid-tight casing, including a fixed bottom half-shell and a vertically mobile top half-shell; a top induction coil, set facing, with interposition of a graphite plate, the crucible, a lateral induction coil and a bottom induction coil vertically mobile for varying the distance from the bottom wall; and means for a.c. electrical supply of the induction coils separately from one another; at least the lateral induction coil includes a plurality of plane turns set on top of one another, and means for selectively short-circuiting, supplying or not supplying the turns, all together or separately one or more at a time and for varying the frequency of supply thereof all together or separately one or more at a time.

Abstract: A device and method for induction hardening rolling tracks of thrust blocks of bearings, according to a required hardening profile. At least two inductors arranged in tandem are used within a track to be hardened, at a predetermined distance from a surface of the track and the thrust block is rotated with respect to the inductors, so as to make them cover the entire track, with a complete 360° turn; the inductors, at least one first pre-heating inductor and one at least heating inductor, are shaped so as to generate a first and a second magnetic fields, respectively, both having flux lines which are perpendicular to each other, and one of the two inductors is mounted on an orientable head so as to be able to arrange the two inductors oriented according to the curvature of the track.