Abstract: An electromagnetic micro positioner, e.g. for use in fibre optics, is operated by a ceramic piston (8) mounted within a ceramic cylinder (5). The piston (8) is moved by a permanent magnet (9) and an electromagnetic circuit (1/2). By changing the coil (2) polarity the piston (8) will either be attracted or repelled to its top or bottom position. In particular the core (1), capable of polarity reversal, has a magnetic remanence by means of which the movable piston (8) is fixable in one of the two predefined positions when the coil (2) is not energized.

Abstract: An electromagnetic micro positioner, e.g. for use in fibre optics, is operated by a ceramic piston (8) mounted within a ceramic cylinder (5). The piston (8) is moved by a permanent magnet (9) and an electromagnetic circuit (1/2). By changing the coil (2) polarity the piston (8) will either be attracted or repelled to its top or bottom position. In particular the core (1), capable of polarity reversal, has a magnetic remanence by means of which the movable piston (8) is fixable in one of the two predefined positions when the coil (2) is not energized.

Abstract: A differential pressure transducer has a measurement chamber which is divided by a membrane into first and second measurement spaces which can be exposed to first and second pressures whereby differential pressure causes deflection of the membrane from its neutral position. A deflection sensor measures the deflection of the membrane and produces a deflection signal. An electromagnet arrangement produces a magnetic force which compensates for the deflection force which is caused by the differential pressure. The coil current for producing the magnetic compensation force represents a measure of the differential pressure.