Electro-magnetic quick-release mechanism for electric switch - has magnetic circuit incorporating bottom wall section of ferromagnetic housing of quick-release mechanism

摘要

The quick-release mechanism uses a release coil (2) receiving the load current enclosing a magnetic core (4) in the form of a cylindrical ferromagnetic sleeve projecting from a bottom pole plate (5). The switch is operated via an impact armature rod (6) of a non-magnetic material, with a permanent magnet (8) above the release coil (2). The magnetic circuit incorporates the permanent magnet (8), the magnetic core (4), bottom pole plate (5) and the bottom wall section (3a) of the ferromagnetic housing (3) of the quick-release mechanism. The housing (3) has a reduced width starting from a point adjacent the permanent magnet (8), allowing a magnetic short-circuit to be provided. -