Door Latch Mechanism - GE JB960 B Technical Service Manual

LOCK MOTOR CYCLE TEST - This test allows
you to run the lock motor through one complete cycle
of operation; testing lock motor operation, and front
and rear latch switch contacts. To perform this test
push and hold the SELF CLEAN key pad - make
sure that the oven door is closed (light switch
depressed). While depressing the SELF CLEAN
pad, the lock motor will run through a complete cycle.
Watch the ERC display closely as it will change
based on the location of the motor and logic switch
contact positions (open or closed).
Illustrations 8a, 8b, 8c, 8d, & 8e show the sequence
of events that will occur during the complete lock
motor cycle. Notice the numbers shown in the left
side of each display represent the position of the lock
motor as well as the logic switch contact positions
(open or closed). While performing the lock motor
cycle test, the words LOCKED DOOR will flash in
the ERC display during 8b and 8d.

DOOR LATCH MECHANISM

The latch mechanism is thermally controlled.
When the SELF CLEAN cycle is selected the ERC
supplies power to the lock motor, driving the motor
towards the LATCHED position. When the lock
motor reaches the LATCHED position, the micro-
switches on the lock mechanism signal the control
board to stop the motor, leaving it in the LATCHED
position. When the oven temperature reaches 560˚
to 650˚ F., the ERC prevents the lock motor from
being energized (DOOR LOCKED).
When the oven sensor senses a temperature of
approximately 300˚F. the ERC once again supplies
power to the lock motor, driving it towards the
UNLOCKED position.
position is reached, the micro-switches on the lock
mechanism signal the control board to stop the
motor, leaving it in the UNLOCKED position.
Latch circuit shown in
UNLOCKED mode
OVEN TEMP
SENSOR
1100 Ω at Room Temp.
2850 Ω at Clean Temp.
8 7
W
When the UNLOCKED
FRONT -
UNLOCK SWITCH
COM
REAR -
LOCK SWITCH
COM
MEAT PROBE
6 5 4 3 2 1
W Y BU O
a
8
b
8
c
8
d
8
e
8
UNLOCKED position
A
Contacts
Open
Contacts
Closed
LOCK MOTOR CYCLE
C
Contacts
Closed
Contacts
Open
LATCHED position
Lock motor circuit shown in
ERC
L
K1 Relay
COM
– 28 –
UNLOCKED POSITION
Rear switch contacts open
Front switch contacts closed
Moving toward LATCHED
POSITION
Rear switch contacts open
Front switch contacts open
LATCHED POSITION
Rear switch contacts closed
Front switch contacts open
Moving toward UNLOCKED
POSITION
Rear switch contacts open
Front switch contacts open
Return to UNLOCKED
POSITION
Rear switch contacts open
Front contacts closed
Moving toward LATCHED
position
Contacts
Open
Contacts
Open
Contacts
Open
Contacts
Open
Moving toward UNLOCKED
position
RUN MODE
LOCK
DOOR
MOTOR
SWITCH
MDL NO
C
NC
B
D
N