The back end of a normal motor is the end that carries the
coupling or driving pulley (NEMA). This
is sometimes called the drive end (D.E.), pulley end (P.E.) etc.
The speed in revolutions per minute (RPM) which a DC motor
develops at rated armature and field voltage with rated load applied.
Bearings reduce friction and wear while supporting rotating
elements. When used in a motor, they
must provide a relatively rigid support for the output shaft.
Bearings act as the connection point between the rotating and
stationary elements of a motor. There
are various types such as roller, ball, sleeve (journal) and needle.
Ball bearings are used in virtually all types and sizes of
electric motors. They exhibit low friction loss, are suited for high-speed operation
and are compatible with a wide range of temperatures. There are various types of ball bearings such
as open, single shielded and sealed.
Rating life, L10, (B10)
is the life in hours or revolutions in which 90% of the bearings selected will
obtain or exceed. Median life (average
life), L50 (B50), is the life in hours
or revolutions in which 50% of the bearings selected will obtain or exceed.
An external device or accessory that brings a running motor
to a standstill and/or holds a load. Can
be added to a motor or incorporated as part of it.
The torque required to bring a motor down to a standstill.
The term is also used to describe the torque developed by a motor during
dynamic braking conditions.
(See Locked Rotor Torque)
The maximum torque a motor will develop at rated voltage without
a relatively abrupt drop or loss in speed.
A piece of current conducting material (usually carbon or graphite)
which rides directly on the commutator of a commutated motor and conducts current
from the power supply to the armature windings.
The device consists of a spring, brush and brush holder, this unit conducts power supply to armature.