Abstract: The invention relates to a method for supplying a paint application device with paint, whereby a determined amount of paint is transported between two scrapers through a scraper line, from a first scraper station which can be connected to a paint supply source, to a second scraper station which can be connected to the paint application device. Said scraper line is cleaned on the return path from the second scraper station to the first scraper station, by a cleaning product which is also transported between the two scrapers. In this way, the scraper line can be cleaned in a reliable manner, with a simple embodiment of the scraper, thus rendering the inventive method especially useful when a color change is carried out.

Abstract: The invention relates to a device for supplying with electric energy a sensor that has a high electric potential and that is used in an enameling line. Said device comprises a light source (1) that has a low electric potential, especially earth potential. Said light source (1) is linked, via an optical waveguide (4), with a light receiver (2) in which a converter (3) is disposed which converts the optical energy to electric energy. The light receiver (2) has the same high potential as the sensor and supplies the latter with the electric energy obtained from the light. This is preferably done via an accumulator (8) that is continuously recharged with the power generated by the converter (3). The invention allows therefore for a practically unlimited service life of sensors in enameling lines.

Abstract: In order to be able to operate a sensor device on a feed pipeline carrying high voltage without using batteries or storage batteries, the sensors are connected for supply purposes via an electrical isolating stage to a mains voltage source and for signal purposes to an evaluation circuit.

Abstract: A device for determining the position of a scraper which is displaceable for the transport of coating material in a supply path of thereof, the coating material comprises a sensor responding to the presence of the scraper. This sensor is accommodated in a separate measuring head, which contains an inner, self-sufficient current source and a circuit arrangement which generates an electric output signal indicating presence or absence of the scraper on the sensor. The information in this output signal is conducted by means of a device, which manages without galvanic connection, preferably via an optical waveguide, to an evaluation circuit, electrically insulated at a distance from the measuring head and which generates an electric output signal used for controlling other parts of the plant. A device of this kind can also be used for detecting scrapers where, as frequently in electrostatically operating coating plants, the sensor has to be attached at a point located at high electric potential.

Abstract: The invention relates to a device for supplying with electric energy a sensor that has a high electric potential and that is used in an enameling line. Said device comprises a light source (1) that has a low electric potential, especially earth potential. Said light source (1) is linked, via an optical waveguide (4), with a light receiver (2) in which a converter (3) is disposed which converts the optical energy to electric energy. The light receiver (2) has the same high potential as the sensor and supplies the latter with the electric energy obtained from the light. This is preferably done via an accumulator (8) that is continuously recharged with the power generated by the converter (3). The invention allows therefore for a practically unlimited service life of sensors in enameling lines.

Abstract: The invention relates to a method for supplying a paint application device (1) with paint, whereby a determined amount of paint is transported between two scrapers (10a, 11a, 10b, 11b) through a scraper line (35a, 35b), from a first scraper station (6a, 6b) which can be connected to a paint supply source (2), to a second scraper station (7a, 7b) which can be connected to the paint application device (1). Said scraper line (35a, 35b) is cleaned on the return path from the second scraper station (7a, 7b) to the first scraper station (6a, 6b), by a cleaning product which is also transported between the two scrapers (10a, 11a, 10b, 11b). In this way, the scraper line (35a, 35b) can be cleaned in a reliable manner, with a simple embodiment of the scraper (10a, 11a, 10b, 11b), thus rendering the inventive method especially useful when a colour change is carried out.

Abstract: A position detector for the position of a pig movable in a pipeline comprises an annular radially magnetized permanent magnet and a magnetic field sensor arranged on the pipeline.

Abstract: In order to be able to operate a sensor device on a feed pipeline carrying high voltage without using batteries or storage batteries, the sensors are connected for supply purposes via an electrical isolating stage to a mains voltage source and for signal purposes to an evaluation circuit.

Abstract: A device for determining the position of a scraper which is displaceable for the transport of coating material in a supply path of thereof, the coating material comprises a sensor responding to the presence of the scraper. This sensor is accommodated in a separate measuring head, which contains an inner, self-sufficient current source and a circuit arrangement which generates an electric output signal indicating presence or absence of the scraper on the sensor. The information in this output signal is conducted by means of a device, which manages without galvanic connection, preferably via an optical waveguide, to an evaluation circuit, electrically insulated at a distance from the measuring head and which generates an electric output signal used for controlling other parts of the plant. A device of this kind can also be used for detecting scrapers where, as frequently in electrostatically operating coating plants, the sensor has to be attached at a point located at high electric potential.