Abstract: The present invention provides a double shell supporting device of a plastic material for a backrest of a seat-group structure with an inner shell part adapted to be a support of the back of a person sitting on the corresponding seat and an outer shell part which functions as a stiffening member.

Abstract: The drive system for cells for fused salt electrolytic production of aluminum is supplied with compressed air via a compressed air network with compressor and compressed air reservoir. It comprises at least one working cylinder with piston and piston rod, a slide valve situated after the junction from the compressed air network, compressed air pipes and a microprocessor. During the thrust movement in the normal work cycle, the working cylinder forms a circuit together with a 5/2 channeling valve, a 3/2 channeling valve and the related compressed air pipelines; the said circuit is fed compressed air via a pressure reducing valve and the compressed air pipeline running from it. By briefly switching over the 5/2 channeling valve normal pressure can be employed and the positive chamber of the working cylinder evacuated, as a result of which the thrusting force supplied by the system can be greatly increased.

Abstract: The drive system for cells for fused salt electrolytic production of aluminum is supplied with compressed air via a compressed air network with compressor and compressed air reservoir. It comprises at least one working cylinder with piston and piston rod, a slide valve situated after the junction from the compressed air network, compressed air pipes and a microprocessor. During the thrust movement in the normal work cycle, the working cylinder forms a circuit together with a 5/2 channeling valve, a 3/2 channeling valve and the related compressed air pipelines; the said circuit is fed compressed air via a pressure reducing valve and the compressed air pipeline running from it. By briefly switching over the 5/2 channeling valve normal pressure can be employed and the positive chamber of the working cylinder evacuated, as a result of which the thrusting force supplied by the system can be greatly increased.

Abstract: A device for high gradient magnetic separation contains, between two pole pieces, an ordered filter structure with parts of magnetic material, which are arranged perpendicular to the direction of a magnetic field and the flow direction of a medium to be filtered, the filter structure comprising flat ribbons with a thickness of less than 100 .mu.m of a material with a coercitive field strength H.sub.c less than 0.2 Oe, which are arranged so that their axes and the normals of their flat sides are approximately perpendicular to the direction of the magnetic field, requiring only a very small field strength for magnetizing the filter structure in order to obtain high flux density gradients.

Abstract: An asymmetric arrangement of busbars for conducting direct electric current is conducted from the cathode bar ends of a transversely disposed aluminum fused salt reduction cell to the anode beam of the next cell wherein a fraction of the busbars connected to the cathode bar ends on the upstream side of the cell are led under the cell such that the busbar configuration in the cathodic part of the cell is such that the variation in the asymmetry of the current leading the cell from the upstream cathode bar ends lies between 3 and 30%.

Abstract: A device for conducting the electric current from the cathode of a hooded, transverse electrolytic cell to the anode of a neighboring cell via cathodically polarized carbon blocks in the pot of a cell, cathode bars and individual conductor bars wherein the current from each cathode bar is passed under a cell to a compensating conductor bar which runs around the neighboring cell. This compensating conductor bar is connected to each anode of the cell it runs around via a flexible conductor strip. Each anode is provided on its uppermost side with a yoke which is inserted and firmly secured in place, together with the conductor strip, in a notch or recess provided in a device for holding the anode in place.The anode holding device remains in place during anode changes and can be adjusted vertically by means of a motor or the like as a function of the voltage or the desired interpolar distance between anode and cathode.

Abstract: With end-to-end electrolytic cells, in particular cells for producing aluminum, high investment and operating costs are incurred by the arrangement of the busbars outside the cell. The magnetic fields produced by the busbars give rise to streaming of the metal in the cell. By providing direct connections between the individual anodes and the electrically connected busbars running along the side of the cell, in a plane just above the anodes, the costs are lowered and the harmful effects of the magnetic fields diminished. A further effect countering the magnetic forces created by the busbars can be achieved by an asymmetric arrangement in which the busbars are at different distances from the cathode bar ends or by connecting an unequal number of cathode bar ends to busbars on opposite sides of the longitudinal axis of the cell.

Abstract: A method of producing a conductor for a superconducting cable or the like is disclosed. The conductor is made up of at least niobium and copper of which the copper is an electrically normal-conducting metal. The method includes heating a niobium carrier to a temperature between 150.degree. and 800.degree.C in a vacuum having a residual gas pressure of at most 10.sup.-.sup.4 Torr, and evaporating copper unto the niobium carrier to form a tightly adhering copper layer thereon. If required, the conductor can be produced to include other electrically normal-conducting metals.