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: 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 high-speed rotary atomizer for applying powder coating comprises in a known manner a housing (1), in which a motor (13) is accommodated. The motor (13) rotates a bell-shaped plate (16) which is disposed at the front of the housing (1). At least one powder supply duct (28, 29, 22, 23, 24, 25, 11, 12, 9, 10) leads through the housing and opens at the front of the housing (1). Its cross section can therefore be kept very large, thereby increasing the powder output of the high-speed rotary atomizer. This also enables a plurality of powder supply ducts (28, 29, 22, 23, 24, 25, 11, 12, 9, 10) to be laid, which in turn results in a higher powder throughput and improved homogeneity of the powder cloud which is produced.