The bending up and distortion of secondary battery plates. It is largely due to over-exhausting the batteries. Where the E. M. F. is never allowed to fall below 1.90 volt it is far less liable to occur.

A collecting or commutator brush for a dynamo or motor, which brush is made of wire gauze rolled up and compressed into shape.

A third brush is sometimes provided in a dynamo for regulating purposes. Applied to a series machine it adjoins one of the regular brushes and delivers its current to a resistance, to whose further end the regular circuit is connected. By a sliding connection the resistance is divided between the third brush circuit and the [...]

Brushes for taking off the current from dynamo commutators, or giving current connection to motors, whose ends are in the form of rollers which rotate like little wheels, and press against the commutator surface.

A third brush, used for application to different parts of a revolving armature commutator to determine the distribution of potential difference between its different members. (See Curve of Distribution of Potential in Armature.) One terminal of a volt-meter is connected to one of the regular brushes, A, of a dynamo; the other to a third [...]

The adjustable (generally) clutch or clamps for holding the commutator brushes of a dynamo, which keep them in contact with the commutator, and admit of adjustment by shifting backward and forward of the brushes to compensate for wear. They are connected to and form part of the rocker, q. v. By rotating the latter the [...]

In a dynamo electric generator, the lead or displacement in advance of or beyond the position at right angles to the line connecting the poles of the field magnet, which is given the brushes. In a motor the brushes are set back of the right angle position, or are given a negative lead.

In electric current generators and motors, the brushes which bear upon the commutator when the machine is in action need occasional adjustment. This is effected by shifting them until sparking between them and the commutator is nearly or quite suppressed.

A brush for a dynamo or motor, which consists of a plate or rod of carbon, held in a brush holder and pressed against the commutator surface.

In electric current generators and motors, the pieces of copper or other material that bear against the cylindrical surface of the commutator are thus termed. Many different constructions have been employed. Some have employed little wheels or discs bearing against and rotating on the surface of the commutator. A bundle of copper strips is often [...]