| 摘要 |
The invention relates to a DC magnet having a coil former (2) which carries the winding and is surrounded by a sheath (4). The ends (11, 28) of the sheath (4) are formed by pole discs which transmit the magnetic flux to a core (8) which is surrounded by the coil former (2) and to its associated moving armature (10). At least on the end (11) associated with the armature (10), the magnetic flux is transmitted by a plurality of pole discs (5, 6) which are electrically insulated from one another, so that an increased initial flux is built up, eddy currents which impede the building up of the magnetic field being prevented in the pole plates (5, 6). The attraction time of a DC magnet (Fig. 1) of such construction is considerably less than in the prior art. The attraction time can be reduced to approximately 1 millisecond by reducing the moving mass of the armature by attachment of an inner cone (26), by an axial slot (27) in the sheath (4) and by a radial slot in the core (8) and/or in the armature (10). <IMAGE>
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