| 摘要 |
1278089 Magnetic switch details SOC D APPAREILLAGE ELECTRIQUE SAPAREL 3 Oct 1969 [6 Jan 1969] 48633/69 Heading H1N An electromagnetic holding device with a spring-biased armature releasable to trip a circuit-breaker has a U-shaped yoke 1 with a release coil 4 on one limb 3 and a permanent magnet 5 adjacent the second limb 2 on the free end of which the armature is rockable on two relatively narrow spaced projections 11 which are between spaced rounded projections 8 of a non-magnetic member 6 which fits over the limb 2 and above the permanent magnet 5. The end of the first limb 3 has a relatively narrow tooth 22 for engagement by the armature in its attracted position and a flux collector 41, 43 is mounted on the member 6 to convey flux from the permanent magnet to the armature. A flux diverting regulating screw 25 is threaded into the yoke 1 and is engaged by an edge 26 of the thermoplastic coil former to restrain the screw in a set position. The surface of the armature which rocks on the yoke may be highly polished and the co-operating yoke parts may be given a matt finish by cold hammering. The base of the yoke 1 is cut away at 21 to increase its reluctance and it is provided with bosses 18 on which the permanent magnet 5 rests. The flux collector 41, 43 may be made of a material such that the effects of temperature change or its reluctance compensates for the effect of temperature change on the other components. |
