Electro-magnets, Interlocking.
Electro-magnets so arranged that their armatures interlock. Thus two
magnets, A A and B B, may be placed with their armatures, M and N, at
right angles and both normally pulled away from the poles. When the
armature M is attracted a catch on its end is retained by a hole in the
end of the other armature N, and when the latter armature N is attracted
by its magnet the armature M is released. In the mechanism shown in the
cut the movements of the wheel R are controlled. Normally it is held
motionless by the catch upon the bottom of the armature M, coming
against the tooth projecting from its periphery. A momentary current
through the coils of the magnet A A releases it, by attracting M, which
is caught and retained by N, and leaves it free to rotate. A momentary
current through the coils of the magnet B B again releases M, which
drops down and engages the tooth upon R and arrests its motion.
Fig. 151. INTERLOCKING ELECTRO-MAGNETS.