fuse
latch switch
pilot
S2
door closed assistant latch switch
(a)
Fig. 2-5
door hook
latch switch
pilot switch
2.4.1
Drawing 2-5(a)
the circuit and construction diagram
of the door interlock switch of brand,
microwave oven. mainly consists of
switch
S2), pilot switch
door
and
of the door interlock switch.
There fixed hooks on the oven
and opened
rectangle hole at the
place at the right of
the oven and the hook.
each rectangle hole,
there fixed a
switch. When the oven door closed,
the two hook on it
into the rectangle hole,
and just push down several micro switches. At that
S2
S3 is cut
and the microwave
oven is under
of
To that
mechanical control microwave oven, no sooner you
the time switch to set the heating time than the
power would be
to the back to start the oven.
To those touch control microwave oven, hardly do you
set the heating time and power, and touch the start
when the power would supplied to the back to
start the oven. When press down the door release
S2
cut off, S3 is closed, and the
oven would stop operating
Provided due to
-
or the appliance
itself reasons, when the door is open, S1, S2
closed, due to the pilot switch (S3)
at conducted
condition would
the 220V voltage
and fused the fuse, and will never
the microwave
oven working when the door is open.
this we can
understand the function of the interlock switch is when
the door is unclosed, the oven wouldn't work, when the
door is opened when the oven is working, it would stop
the working immediately (FIG.2-5b).
2.4.2
AND POWER
Time and power distributor is mainly composed of timer
motor and two sets of gear switch S4 and S5. When
the timer is at zero
the gear switches
cut
off, when the heating time is settled, the gear switch is
closed. When
the oven, the time motor
working. When it reaches the settled time, it would cut
off the gear switch (s4) to step the oven working. The
gear switch (S5) is designed for controlling the output
of the microwave oven, actually for controlling the
output of the magnetron. It mainly by the method which
the magnetron working internally at the same
working point to change the output of the magnetron.
This method was called
CONTROL". But there is another method which is
called "ELECTRIC LEVEL CONTROL" which is
through changing the working point (such as anodę
voltage or magnetic
to change the output of the
2-6
magnetron. Because of conduction ratio control
method is Iow cost, high function and high
it is widely used for those
oven which have the
door release button
Fig.
2-5 (b)
timer & power motor
l
220V
6
