| 摘要 |
<p>The solenoid includes a magnetic coil and longitudinally shiftable armature with a magnetic counter pole. The armature can be mounted in an appropriate manner, e.g. by a piston rod of non-magnetic material mounted in bearing bushes of the counter pole. The facing sides of the armature and counter pole have a stepped configuration, in the region of which appears a high density of the magnetic field lines of force. The stepped configuration (3,4) is of such shape that a multiple concentration of the lines of force (Pm) takes place. Preferably the step shape is such that this densifying appears at several points of the effective region between the armature (1) and the counter pole (2). The step configuration may consist of an annular protrusion (3) and a matching annular groove (4), both being mutually coaxial and symmetrical to the centre line (5) of the armature and counter pole.</p> |
