Sharp R-240B Service Manual page 24

R-240B
1ST. LATCH SWITCH, 2ND. LATCH SWITCH, STOP SWITCH AND MONITOR SWITCH REMOVAL
1. CARRY OUT 3D CHECKS.
2. Disconnect wire leads from the switches and control
panel.
3. Remove the control panel assembly from the oven
cavity front flange. Refer to chapter "CONTROL PANEL
ASSEMBLY REMOVAL".
4. Remove two (2) screws holding latch hook to oven
flange.
5. Remove latch hook assembly from oven flange.
6. To remove the secondary interlock switch.
6-1. Pull out the 1st. latch switch from the latch hook, by
pushing outward on the tab that is holding the switch.
But the switch will be caught by the bar of the latch
hook.
6-2. Then pull out the switch while pushing the plunger of
the switch again.
6-3. Now the 1st. latch switch is free.
7. To remove the monitor switch, stop switch or 2nd. latch
switch.
7-1. With pushing outward on the tab that is holding the
switch, turn the switch so that the pole is an axis.
7-2. Pull out the switch from the latch hook. Do not break
the pole or tab of the latch hook.
7-3. Now the switch is free.
Re-install
1. Re-install each switch in its place. The 1st. latch switch
is in the lower position and the monitor switch is in the
1ST. LATCH SWITCH, 2ND. LATCH SWITCH, STOP SWITCH AND MONITOR SWITCH ADJUSTMENT
1. CARRY OUT 3D CHECKS.
If the 1st. latch switch, 2nd. latch switch, stop switch and
monitor switch do not operate properly due to a
misadjustment, the following adjustment should be made.
2. Loosen the two (2) screws holding the latch hook to the
flange of the oven front face.
3. With the door closed, adjust latch hook by moving it
back and forth and up and down. In and out play of the
door allowed by the upper and lower position of the
latch hook should be less than 0.5mm. The horizontal
position of the latch hook should be adjusted so that the
monitor switch and the 2nd. latch switch are activated
with the door closed. The vertical position of the latch
hook should be adjusted so that the stop switch and the
1st. latch switch are activated with the door closed.
4. Secure the screws firmly.
5. Check the operation of all switches. If each switch has
not activated with the door closed, loosen screw and
adjust the latch hook position.
After adjustment, make sure of the following.
1. In and out play of the door remains less than 0.5mm
when in the latched position. First check upper position
of latch hook, pushing and pulling upper portion of door
toward the oven face. Then check lower portion of the
latch hook, pushing and pulling lower portion of door
toward the oven face. Both results (play in the door)
middle position. The stop switch and 2nd. latch switch
are in the upper position.
2. Re-connect wire leads to each switch. Refer to chapter
"Pictorial Diagram".
3. Secure latch hook (with two (2) mounting screws) to
oven flange.
4. Re-install the control panel assembly to the oven
cavity front flange.
5. Re-connect wire leads to the control unit. Refer to
chapter "Pictorial Diagram".
6. Make sure that monitor switch is operating properly
and check continuity of the monitor circuit. Refer to
chapter "Test Procedure", and Adjustment Procedure
below.
Pole
Pole
Monitor
Switch
1st. Latch
Switch
Figure C-6. Latch Switch Removal
should be less than 0.5mm.
2. The 1st. latch switch, 2nd. latch switch and stop switch
interrupt the circuit before the door can be opened.
3. The monitor switch contacts close when the door is
opened.
4. The contacts of 1st. latch switch, 2nd. latch switch and
stop switch open within 1.6mm gap between right side
of cavity face plate and door when door is open.
5. Re-install outer case and check for microwave leak-
age around the door with an approved microwave
survey meter. (Refer to Microwave Measurement Pro-
cedure.)
1st. Latch
Door
Switch
Figure C-7. Latch Switch Adjustments
22
Latch Hook
2nd. Latch
Switch
Stop
Switch
Tab
Bar
Tab
Latch Heads
Latch Hook
2nd. Latch
Switch
Stop
Switch
Monitor
Switch