magnet system guide for a lifting appliance

摘要

The magnet system for a lifting appliance contains a cylindrical armature which can move along an axis, an excitation coil and a magnet iron system for guiding the magnetic field. The magnet iron system is provided with a cross-section, which is greater than the armature cross-section, at its points which deflect the magnetic field and at which the magnetic lines of force must exhibit a deflection angle as a result of the direction change, in order to reduce the magnetic flux density at these points in the magnet iron system. Furthermore, the magnet system is advantageously of symmetrical construction in such a manner that the lifting path of the armature is located at least approximately in the inductive centre of the excitation winding and likewise coincides such that it is superimposed with the plane of symmetry of the magnetic energy content of the two ferromagnetic housing halves which are virtually of identical size. Advantage: Increase in the lifting lines of force with a power requirement of the same magnitude, and dimensions of the same magnitude with respect to previous magnet systems within the lifting path; improvement in the efficiency in both current-surge and continuous operations.