Abstract: Snap-action spring device for load-reversing switches of multiple contact switches whose spring can be loaded by a drive. In conventional load-reversing switches, a gear moves a cam disk to and fro between two end positions, so that the contacts which close last during the movement in one direction are the first to open during the reverse movement and vice versa. This rigid sequence of contacts is unsuitable for thyristor load-reversing switches. The invention proposes that the driven element be connected to a coupling element which can rotate in one direction only independently of the direction of rotation of the drive. This permits automatic contact sequence control and precludes switching errors, in a simpler manner.

Abstract: The invention relates to a circuit arrangement for switching current from a contact to a thyristor connected in parallel to the contact. In the inventive circuit arrangement ohmic resistances (7, 8, 9, 10) are connected in parallel to the contact (1), whereby each ohmic resistance (7, 8, 9, 10) can be individually disconnected by means of a delayed-opening contact (3, 4, 5, 6) and the disconnection times are staggered. In this manner, it is possible to accomplish stepwise current switching and thus reliably prevent arcing at the contact (1).

Abstract: An impedance coil core which includes a plurality of core legs and yokes which interconnect the core legs in an assembled condition of the core is provided with aligned recesses in the yokes and in the core legs for accommodating tensioning bolts which extend into the recesses and press the yokes against the core legs in the assembled condition. Each of the core legs includes a plurality of laminated assemblies including sheet metal elements. Those portions of the yokes and at least of the laminated assemblies adjoining the latter are provided with non-magnetic intermediate layers in the central region which is provided with the recesses. The intermediate layers in the core legs are wedge-shaped and diverge toward the adjacent yokes, and the intermediate layers in the yokes are cross-sectionally rectangular.

Abstract: A thermometer for measuring the temperature of at least one selected portion of an electrically-operated device disposed in a container includes a first upwardly extending conduit adapted to communicate interiorly with the container, and an indicating capacitor defining a first chamber communicating with the first conduit. The indicating capacitor includes a first dielectric material, and a first electrically non-conducting liquid having a predetermined coefficient of thermal expansion; the first liquid is adapted to be disposed at least in part in the container, and at least in part in the first chamber and the first conduit, so that at least a portion of the first dielectric material is constituted by a portion of the first liquid. A reference capacitor defines a second chamber, and includes a second dielectric material.

Abstract: Method for maintaining the temperature level of metal melts of specified compositions, comprising the steps of a/ excluding oxygen access to a melt contained in a furnace; b/ slowly displacing the atmospheric air from above the melt surface by introducing an inert protective gas, in laminar flow, without the generation of turbulence; and c/ thereafter maintaining above the melt surface a pure protective gas atmosphere, to meet a consumption of between 0.1 and 1% of the volumetric capacity of the furnace per minute, this permitting the melt to be cast in several pours or continuously without oxidaton of the alloying components and without increase in its gas content, even hours after having been melted down.