Operating instructions

37Mechanical and electrical design
0912
55
Motor
Gears with pulley
and centrifugal
clutch
V-belt
Wedges
Drive motor
Description
The motor is mounted on top of the outer drum,
on stepped feet to provide a means of adjusting
the belt tension. The motor drives the drum
through a gearbox and centrifugal clutch via a
V-belt.
The motor consists of stator, rotor and end-
shields with ball-bearings. The stator and the
rotor consists of plates, insulated from each other
and welded together. The stator is provided with
slots in which three windings are wound (one 6-
pole for washing action, one 4-pole for distribu-
tion speed and one 2-pole for extraction. The
windings are impregnated with a temperature-
resistant sound-insulating resin varnish according
to class B. The end-shields are die-cast. The ball
bearings are permanently lubricated.
The gearbox and centrifugal clutch are mounted
in one housing on the motor shaft, with the outer
casing serving as the belt drive pulley. At
washing action speed, the clutch is disengaged,
with the result that the motor drives the pulley
through a gear reduction. At spin speed, the
centrifugal clutch engages and gradually locks
the planet carrier to the pulley casing. The pulley
is thus accelerated up, by conventional clutch
action, to full spin speed, at which speed it is
rotating at the same speed as the motor shaft.
This arrangement provides a change from
washing action speed to spin speed, that
requires only one drive motor.
Stepped motor mounts on the outer drum provide
a means of adjusting the belt tension. Four bolts
secure the motor to the outer drum. Wedge-
shaped mounts with a number of steps between
the motor feet and the mounting points allow the
motor position to be adjusted to give the required
belt tension.
The motor incorporates a thermal overload
protector, embedded in the motor windings. If the
temperature of the windings exceeds about 150°
C, the contact interrupts the circuit to the motor
contactors.
Tensioning the drive belt
1. Slacken the motor securing bolts.
2. Adjust the position of the step wedges until
the correct belt tension is obtained. Always
adjust the wedges in pairs so that the
motor shaft remains parallel to the drum
shaft.
3. Retighten the nuts securing the motor.
Fig.
55