Abstract: The present invention discloses a process for producing a high-quality insulation for conductors or conductor bundles of electrical machines by means of spray-sintering. Unlike in the prior art, it is possible to apply internal corona-discharge protection, insulation and external corona-discharge protection to conductors or conductor bundles in which, on account of a very low level of defects in the insulation and its inherent resistance to partial discharges, it is possible to dispense with the use of winding processes using glass/mica tapes. This eliminates the need to use complex special equipment and allows the throughput times to be shortened considerably.

Abstract: A process for producing insulations for electrical conductors by powder coating, which results in aging which is improved compared to glass-mica or casting-resin insulation, and a powder which is suitable for such a process. The powder is applied a number of times in succession, in the form of individual layers which follow one another, until a layer thickness of ?10 mm is reached, and each of the individual layers undergoes intermediate heat curing before the next individual layer is applied. The intermediate curing of each individual layer uses a curing time which corresponds to 2-10 times the gel time of the powder used. Finally, the entire insulation undergoes final curing. The result of an electrical life test carried out on various specimens insulated with epoxy-resin powder which contains fine filler.

Abstract: The invention discloses a process for producing a high-quality insulation on a conductor or conductor bundle of rotating electrical machines, in which, in successive immersion passes in a fluidized-bed sintering tank, internal corona-discharge protection, insulation and external corona-discharge protection are applied, in each case with layer thicknesses of ≦0.2 mm. The sintering and curing take place at temperatures of approx. 200° C., so that it is possible to use materials which satisfy the demands which are imposed on the insulation of conductors or conductor bundles of this type for rotating electrical machines. Furthermore, the production process, in particular the layer thickness selected for the individual layers, ensures that the individual layers are free of defects, so that it is impossible for there to be any partial discharges, which would otherwise lead to damage to the insulation.

Abstract: It is an object of the invention to provide a process for producing insulations for electrical conductors by means of powder coating, which results in aging which is improved compared to glass-mica or casting-resin insulation. It is also intended to describe a powder which is suitable for such a process. For this purpose, the powder is applied a number of times in succession, in the form of individual layers which follow one another, until a layer thickness of ≦10 mm is reached, and each of the individual layers undergoes intermediate heat curing before the next individual layer is applied. The intermediate curing of each individual layer uses a curing time which corresponds to 2-10 times the gel time of the powder used. Finally, the entire insulation undergoes final curing. The result of an electrical life test carried out on various specimens insulated with epoxy-resin powder which contains fine filler and has been applied in accordance with the invention is illustrated in the only FIGURE.

Abstract: The present invention discloses a process for producing a high-quality insulation for conductors or conductor bundles of electrical machines by means of spray-sintering. Unlike in the prior art, it is possible to apply internal corona-discharge protection, insulation and external corona-discharge protection to conductors or conductor bundles in which, on account of a very low level of defects in the insulation and its inherent resistance to partial discharges, it is possible to dispense with the use of winding processes using glass/mica tapes. This eliminates the need to use complex special equipment and allows the throughput times to be shortened considerably.

Abstract: The invention discloses a process for producing a high-quality insulation on a conductor or conductor bundle of rotating electrical machines, in which, in successive immersion passes in a fluidized-bed sintering tank, internal corona-discharge protection, insulation and external corona-discharge protection are applied, in each case with layer thicknesses of ≦0.2 mm. The sintering and curing take place at temperatures of approx. 200° C., so that it is possible to use materials which satisfy the demands which are imposed on the insulation of conductors or conductor bundles of this type for rotating electrical machines. Furthermore, the production process, in particular the layer thickness selected for the individual layers, ensures that the individual layers are free of defects, so that it is impossible for there to be any partial discharges, which would otherwise lead to damage to the insulation.

Abstract: A powder-spraying apparatus having simultaneous internal and external charging, which is suitable for electrostatic powder coating. In order to achieve improved constancy of the deposition efficiency, largely independent of the distance between the powder-spraying apparatus and the work piece, it is proposed to connect both internal high-voltage electrodes and external high-voltage electrodes to a high-voltage source via high-resistance components.

Abstract: Workpieces are electrostatically coated with powder materials. It is possible to attain a relatively large coating thickness in a single operation by simultaneously or alternately coating with powder particles that have a different electrical charge. The process can be used in applying single-component or multi-component coating materials.

Abstract: A method and an apparatus for powder spraying can be used, for example, for electrostatic enameling. In order to achieve an easily regulatable high powder output rate, it is proposed to fluidize powder in a closed container, extract it in the region of the fluid bed and cause it to emerge through a nozzle on the container. The container is subdivided by a frit into a first chamber to which air is fed and a second chamber which contains the powder and out of which air is discharged through a valve. A powder output rate can be regulated by the regulation of air pressures.

Abstract: A method and a device for controlling the outflow of fluid powder from a container can be used for controlling the expulsion of powder out of a powder-spraying apparatus for electrostatic coating. The disadvantages of a mechanical closing device are avoided by introducing closing air into an extraction pipe for extracting fluidized powder out of a container. The closing air is introduced through a pipe which opens into an orifice in the casing of the extraction pipe. The mass flow of fluidized powder can be controlled by an appropriate setting of a pressure in the extraction pipe in relation to the pressure in the fluid bed, that is to say by the introduction of closing air at an appropriate pressure.

Abstract: A piston valve for liquids provides potential isolation between an inlet-side and an outlet-side liquid. The piston valve is suitable, in particular, for controlling water-based paints in painting appliances which operate by electrostatic charging. At least one control electrode which is at the electric potential of the liquid present at the outlet of the valve is provided in order to improve the service life of the valve.

Abstract: A process is provided for producing an anode for an electrochemical cell, in particular a solar cell, on electrically conductive glass to which a layer of porous metal oxide is applied. The layer includes metal complexes of the porphyrin-phthalocyanine class and other dyestuffs and is then subjected to a heat treatment. A paste of highly dispersed metal oxide, in particular aluminum oxide and/or titanium oxide, is first produced with the addition of a dyestuff and an alcoholic solution, which acts as a binder, in a dry atmosphere. The paste produced in this way is applied as a thin layer to the glass plate coated with a transparent, electrically conductive layer, and the configuration including the glass plate and the pasty metal oxide layer is subjected to a heat treatment at temperatures below 300.degree. C.