Comb.
A bar from which a number of teeth project, like the teeth of a comb. It
is used as a collector of electricity from the plate of a frictional or
influence electric machine; it is also used in a lightning arrester to
define a path of very high resistance but of low self-induction, for the
lightning to follow to earth.
Communicator.
The instrument by which telegraph signals are transmitted is sometimes
thus termed.
Commutator.
In general an apparatus for changing. It is used on electric current
generators, and motors, and on induction coils, and elsewhere, for
changing the direction of currents, and is of a great variety of types.
Synonym--Commuter (but little used).
Fig. 106. DYNAMO OR MOTOR COMMUTATOR.
Commutator Bars.
The metallic segments of a dynamo or motor commutator.
Commutator, Flats in.
A wearing away or lowering in level of one or more metallic segments of
a commutator. They are probably due in many cases to sparking, set up by
periodic springing in the armature mounting, or by defective commutator
connections.
Commutator of Current Generators and Motors.
In general a cylinder, formed of alternate sections of conducting and
non-conducting material, running longitudinally or parallel with the
axis. Its place is on the shaft of the machine, so that it rotates
therewith. Two brushes, q. v., or pieces of conducting material, press
upon its surface.