Sharp R-870B, Service Manual

Page: 33 / 48

R-870B
31
If the 1st. latch switch, 2nd. interlock relay control switch
and monitor switch do not operate properly due to a mis-
adjustment, the following adjustment should be made.
1. CARRY OUT 3D CHECKS.
2. Loosen the two (2) screws holding the latch hook to the
oven cavity front flange.
3. With the door closed, adjust the latch hook by moving
it back and forward or up and down. In and out play of
the door allowed by the latch hook should be less than
0.5 mm. The horizontal position of the latch hook
should be placed where the monitor switch has acti-
vated with the door closed. The vertical position of the
latch hook should be placed where the 1st. latch switch
and 2nd. interlock relay control switch have activated
with the door closed.
4. Secure the screws with washers firmly.
5. Make sure of the 1st. latch switch, 2nd. interlock relay
control switch and monitor switch operation. If those
switches have not activated with the door closed, two
(2) screw holding latch hook to oven cavity front flange
and adjust the latch hook position.
After adjustment, make sure of following:
1. In and out play of door remains less than 0.5 mm when
1ST. LATCH SWITCH, 2ND. INTERLOCK RELAY CONTROL SWITCH
AND MONITOR SWITCH ADJUSTMENT
latched position. First check latch hook position, push-
ing and pulling the door toward the oven face. The
results (play of the door) should be less than 0.5mm.
2. The contacts (COM-NO) of the 1st. latch switch and
2nd. interlock relay control switch interrupt the circuit
before the door can be opened.
3. The contacts (COM-NC) of the monitor switch close
when the door is opened.
4. Re-install outer case and check for microwave leakage
around the door with an approved microwave survey
meter. (Refer to Microwave Measurement Procedure.)
Figure C-4 Latch Switches Adjustment
GRILL HEATERS (TOP HEATERS) REMOVAL
1. CARRY OUT 3D CHECKS.
2. Remove the one (1) screw holding the exhaust duct to
the oven cavity.
2. Remove the exhaust duct from the oven cavity.
4. Disconnect the wire leads from the grill heaters.
5. Lay down the two (2) tabs holding the reflector to the
oven cavity.
6. Remove the reflector from the oven cavity by sliding it
leftward.
7. Remove the grill heaters and the short terminal to-
gether from the oven cavity top plate.
8. Remove the two (2) screws holding the short terminal
to the grill heaters.
9. Now the individual grill heaters are free.
BOTTOM HEATER REMOVAL
1. CARRY OUT 3D CHECKS
2. Remove the fan duct from the oven cavity, referring to
"FAN MOTOR REPLACEMENT".
3. Disconnect the wire leads from the bottom heater.
4. Remove the two (2) nuts holding the bottom heater with
the bottom heater angle and the heat seal spring to the
oven cavity right wall.
5. Remove the two (2) nuts holding the bottom heater with
the bottom heater angle and the heat seal spring to the
oven cavity left wall.
6. Remove the bottom heater from the oven cavity .
1. CARRY OUT 3D CHECKS.
2. Remove the control panel assembly referring to "CON-
TROL PANEL ASSEMBLY REMOVAL".
3. Disconnect the leads from all switches.
4. Remove the two (2) screws holding the latch hook to
the oven cavity.
5. Remove the latch hook.
6. Push the retaining tab slightly and remove the switch.
1ST. LATCH SWITCH, 2ND. INTERLOCK RELAY CONTROL SWITCH, AND MONITOR SWITCH REMOVAL
Figure C-3. Switches
Tab
Tab
Tab
1st. Latch Switch
2nd. Interlock
Relay Control
Switch
Monitor Switch
Latch Hook
Latch Hook
Latch Heads
Door
1st. Latch Switch
2nd. Interlock
Relay Control
Switch
Monitor Switch
Switch Lever