Magnetic latch and switch using cobalt-rare earth permanent magnets

Claim 2

A device according to claim 2 wherein said device is an electrical switch and further includes a pair of contacts engaged by said reed spring armature in the released position.

Claim 3

A high speed magnetically operated device comprising a multipole magnet assembly including a plurality of linearly arranged alternating cobalt-rare earth permanent magnets and ferromagnetic pole pieces having alternately oppositely poled pole faces, and a plurality of flux diversion coils each mounted between a pair of adjacent pole pieces that each selectively produces a magnetic field with a polarity to shunt the magnetic flux produced by the associated permanent magnet mounted between the same pair of pole pieces, a ferromagnetic armature attracted by magnet forces to a latched position against the pole faces of said magnet assembly, and movable under the influence of a biasing force to a released position, wherein said cobalt-rare earth permanent magnets and pole pieces have a relatively thin field direction dimension as compared to the area coordinate dimensions, and said armature is a low volume armature with a relatively small thickness dimension as compared to the area coordinate dimensions, circuit means for temporarily applying only one polarity of direct current to said flux diversion coils to reduce the magnetic forces acting on said armature and release said armature for movement to the released position, and mechanical restoring means for returning said armature to the latched position magnetically attracted to said magnet assembly.