Abstract: An electric filter, for example an harmonic filter in an HVDC convertor, has, in addition to the main filter, a low power model filter having the same frequency characteristic as the main filter. The model filter is supplied with a voltage which is a scaled-down version of the voltage appearing across the main filter. The currents in the main and model filters are sensed at corresponding places in the filters and compared. If a deviation occurs between the sensed currents in the main and model filters, an indicating signal is generated which indicates a deterioration in the performance of the main filter.

Abstract: A method of, and means for, controlling the manufacture of a winding for an inductive apparatus, for example a transformer winding or a reactor winding, which winding is of the kind comprising a plurality of turns of a sheet composed of an electrically conductive metallic foil and an electrically insulating film on each side of the metallic foil. During the winding of the sheet, the metallic foil together with the insulating films is passed through at least one electrode device which comprises at least two rolls arranged one on each side of the sheet and having a different voltage compared with the metallic foil. At the electrode device, the insulating films are pressed with a certain pressure against the metallic foil across the entire width of the latter by means of the rolls, and the electrical insulation of both sides of the sheet is checked by separately sensing the leakage current which via each of the rolls passes through the respective insulating film.

Abstract: The invention relates to a fiber-optically coupled measuring device which has an optically energized transducer section which produces signal information in an optical form, the energy supply for the transducer section and the signal information therefrom being transmitted via a light guide fiber. The signal information is transmitted to a receiver at a location remote from the transducer section, the signal information being modified in response to electrical signals fed to a light emitting component of the transducer section.

Abstract: The invention relates to a regulating winding for a transformer in which a plurality of helical current-carrying conductor loops are connected in series with each other, whereas a plurality of non-current-carrying helical potential control loops are provided adjacent to the current-carrying loops and are connected to appropriate ones of the current-carrying loops in such a way that a substantial increase in the series capacity of the regulating winding is obtained with a relatively small increase in the space required for the regulating winding.

Abstract: A pressure-sensing transducer which can be used to continuously measure the pressure in the cylinder of an internal combustion engine comprising a pressure-transmitting element which includes a generally tubular seat and a metallic plate which closes off a top end of the seat, an M-shaped force-transmitting member which spans across the top end of the seat, the outer legs of the M-shaped member being connected to opposite portions of the top end of the seat and the inner legs being connected to the center of the metallic plate, and a magnetoelastic force-sensing member connected between the outer legs of the M-shaped member, such that pressure-generated forces applied to the metallic plate from within the generally tubular seat are transformed into a tensile force acting on the force-sensing member in a direction perpendicular to the longitudinal axis through the generally tubular seat.

Abstract: The present invention relates to a protection device for detecting at least one faulty phase in an electrical network. The device comprises a band exclusion filter for each phase for filtering away the signals which have the same frequency as the nominal frequency of the network, amplifiers, rectifiers and peak value forming means for each phase. In addition, the different phase signals are fed to a function element which delivers a signal to a level and comparison device for each phase, where the signal is compared with the signals in the respective phase.

Abstract: The invention relates to a fiber optic temperature-measuring apparatus, based on the photo-luminescence of a solid material which is subjected to the temperature to be measured. The apparatus is characterized in that several sensors made of such a temperature-sensitive luminescent material are located in various places, each one being connected to a light-emitting diode via at least one optical fiber. Luminescent light emitted from each sensor is arranged to be supplied, via at least one separate optical fiber, possibly partially via the above-mentioned fiber and a fiber branch, to a receiver unit, common to all the sensors, the excitation light signal from each light-emitting diode being time-division multiplexed.

Abstract: A container for enclosing particulate or piece-formed radioactive material which is to be converted into a solid body by isostatic pressing at a high temperature and a high pressure. The container may have a corrugated sheath and suitably a plane lid and a plane bottom. The corrugation makes possible axial compression of the container prior to the pressing. The container may also have a cylindrical sheath and bellows projecting into the sheath and joining the sheath of the container to a lid and a bottom. The bellows make it possible to insert the lid and the bottom by gas pressure, so that the material present in the container is axially compressed.

Abstract: An apparatus for regulating the fiber concentration of a fiber suspension during transport of the fiber suspension through a conduit which comprises a variable speed-controlled electric motor driving a pump for impelling the fiber suspension through the conduit to an outlet of the latter. A system is provided for obtaining a measure of the power supplied by the motor to the pump and for dividing this measure by a signal proportional to the flow rate of the fiber suspension in the conduit. The resulting signal, which is proportional to the fiber concentration in the fiber suspension, is employed to regulate the speed of the pump motor.

Abstract: An electromagnetically operated electric switch combines the function of a contactor and a current-limiting circuit-breaker. The contact assembly of the switch includes two contact systems, which are different in function, with a fixed contact which is common to both systems. The first contact system is intended for normal operating current connections, whereas the other contact system is intended for breaking short-circuit currents. The contact-making elements in the two contact systems can be made of different contact materials, in order to obtain a long electrical and mechanical life.

Abstract: A coil having a slot portion intended to be arranged in slots in a stator or a rotor of an electrical machine is manufactured by forming a coil part including a bundle of electrically insulated conductors and insulation surrounding the bundle, arranging a portion of the coil part in a mould including at least two mould parts, surrounding the mould with a heat-shrinkable material which is penetrable by an impregnating resin, subjecting the thus composed product to pressing and heating in a tool which together with the mould gives the slot portion its final shape, the mould parts being spaced from each other to provide longitudinal gaps between their confronting longitudinal edges, and the heating of the product causing the heat-shrinkable material to shrink and retain the slot portion in its final shape after removal of the composite product from the tool, thereafter impregnating the insulation with an impregnating resin and transforming the insulation into a solid state.

Abstract: The present invention relates to a method for mounting transformer windings on the core legs. After all the windings for a core leg have been pre-assembled, they are pressed in a separate press to the desired height, whereafter the windings are provided with screw clamps or the like, applicable from the outside, which hold the windings in a compressed position until they have been applied on a core leg and the upper yoke of the transformer has been interleaved and the press beams been mounted. Thereafter, the screw clamps are removed.

Abstract: In visibility measuring apparatus, a transmitter including at least one transmitter optic for emitting light signals and at least one receiver including at least one receiver optic for receiving the emitted light signals are positioned in a measuring base defined by the distance between the at least one transmitter optic and the at least one receiver optic. A central unit controls the light emitting signals and processes the light signals received from the at least one receiver optic. Signal light conductors interconnect at least some of the transmitter and transmitter optics, the central unit and the transmitter and the receiver optics and the central unit. In a modified embodiment each measuring base may include a separate transmitter optic and a separate receiver optic. Additionally, calibration signals may be transmitted from the central unit to each receiver optic by additional light conductors with separate light conductors for returning a reference signal from each receiver optic to the central unit.

Abstract: An organic ion exchange material, which comprises a mixture of grains of a first type bearing groups containing exchangeable hydrogen ions and grains of a second type bearing groups containing exchangeable hydroxyl ions and which has been used in a cleaning circuit in a nuclear reactor, is subjected to a treatment before the ion exchange material is further processed for final storage of the radioactive waste products contained therein. The treatment comprises removing hydrogen ions and/or hydroxyl ions or groups containing hydrogen ions and/or groups containing hydroxyl ions from the grains, whereafter the grains of the first type are separated from the grains of the second type, before the grains of each type are further processed separately for final storage of the radioactive waste products contained therein.

Abstract: Composite material comprising a matrix of an alloy of about 64 percent by weight iron and about 36 percent by weight nickel or of a different alloy containing iron and nickel having a coefficient of thermal expansion of at the most 3.10.sup.-6 K.sup.-1 within the temperature range 20.degree. C. to 100.degree. C. and veins of copper, distributed in one direction through the matrix, with the copper and the alloy metallurgically bonded to each other through a boundary layer containing copper and the alloy having a thickness of at the most 5 .mu.m.

Abstract: The invention relates to a strip or sheet mill having working rolls, backup rolls and axially displaceable intermediate rolls positioned therebetween. Associated with the rolled strip of the rolling mill is a flatness measuring device (e.g., for measuring the distribution of the strip tension over the strip width), the output signals of the flatness measuring device being fed, together with signals representing the strip width, to at least two different evaluating members, one of these serving to deliver a regulating signal for adjusting the crown of the working rolls, and the other serving to deliver a regulating signal for adjusting the axial positions of the intermediate rolls.

Abstract: The invention relates to a method and device for generating and presenting an image on a visual display unit or some other display member. The image is composed, for example by an operator via a keyboard, of a plurality of symbols defined in advance in a symbol memory, which are placed on the image adjacent to each other. Each symbol is associated with at least one predetermined entry point and at least one predetermined exit point. When creating the image, a symbol is placed so that an entry point of that symbol is located immediately adjacent to an exit point of a previously displayed symbol.

Abstract: A power amplifier connection comprises a switching amplifier and a proportional amplifier. The output signal from the switching amplifier and the output signal from the proportional amplifier are supplied to a summation member which, by addition of the two output signals, forms the resultant output signal of the amplifier connection. The switching amplifier is adapted to be controlled in dependence on the input signal of the amplifier connection in such a way that its output signal endeavours to follow the input signal. The proportional amplifier is adapted to be controlled in dependence on the deviation between the input signal and output signal of the amplifier connection.

Abstract: A method for manufacturing an article to an intended near final shape and size with powder as the starting material. The powder is placed in a first capsule having the shape of the desired article and a size which allows for a suitable decrease in volume when pressing the powder into a solid body. This first capsule is placed in a second larger capsule and is surrounded on all its sides by a medium which is viscous at the compression temperature. The second outer capsule with its contents is heated, inserted into a press chamber, and surrounded by a readily deformable heat-insulating material such as talcum powder. A piston is inserted into the press chamber and acts to generate a pressure which compresses the material in the first capsule into a homogeneous, solid body.

Abstract: A method for manufacturing elongated dense bodies of metals or metal alloys by extrusion of a powder charge enclosed in a metal capsule. A closed, powder-filled capsule is heated to a temperature necessary for bonding the charge under pressure, and the capsule is then inserted in a pressure chamber and surrounded by a layer of a solid, readily deformable material, such as talcum powder or pyrophyllite. A piston is inserted into the pressure chamber and subjects the capsule and the surrounding material to a pressure such that the capsule and the surrounding material are pressed out together through an opening in a die. Tubes can also be extruded, with the deformable packing material filling the tube bore.