Timex DYNABEAT 253 - Page 14

Operation of the Model 253 Movement
THIRD WHEEL
FIGURE L
t
RUNNING POSITION
FIGURE M
STOP POSITION
FRICTION SPRING
CROWN SET STEM
Setting friction for the dial
train is provided by a spring
connecting the friction pinion
and the third wheel as shown
in Figure L.
The friction pinion and third
wheel may be separated by
lifting the friction pinion with
tweezers. It is not necessary to
remove the friction spring from
the third wheel.
To reassemble, press the fric-
tion pinion firmly back into
place in the third wheel.
The balance stop mechanism is
purely mechanical.
Fiqure M shows the stop mech-
anism in the runninq position.
In
the running position the tip
of the stem butts against the
stop lever and keeps the tip of
the stop lever away from the
impulse disc.
Figure N shows the stop mech-
ani5m in the stopped position
(when the stem is pulled out
into the set position) in the
stopped position, the tip of the
stop lever butts aqainst the im-
pulse disc on the balance wheel
assembly and stops the balance
wheel assembly.
In the stopped position, there
is no electrical contact so there
is no current drain to shorten
the life of the energy cell.
253 . 13