Canon NP-70 Service Manual page 60

NP•70
3-19
Block Actions Occurring
If the copy being made is the last copy, the copy selector will be released by the
STEP SCF
forward motion of the copyboard (see STEP SCH ).
The activation of MS 14 by the advancing copyboard causes the pickup of paper
as well as the other actions shown. The purpose of energizing K10 is to provide
a path for energizing relay K 11 when the next MS3A pulse occurs (see
STEP 6CF
STEP 7CH ~ ).
The forward advance of the copyboard releases MS 14 (activated above) and,
permits the feeding of the copy paper up to the drum for transfer of. the image
to the paper. Additionally, C25 begins discharging to hold relay K10 energized
STEP 7CF
until after the next MS3A pulse (see STEP 9CH ).
As K10 is still ON, the actuation of MS3A by the rotating drum energizes relay
K11 to turn the jam circuit ON. This turn-on occurs ~t the beginning of the
copy cycle and K11 will remain energized only until after the copy exits the
machine. Then it will be deenergized until the next copy. This is similar to
STEP SCF
STEP 12CH but will occur every copy cycle rather than once in a copy ope-
ration series as was the case in "half-size" copying.
Capacitor C25 finishes the discharging action in STEP 7CF and causes K 10
STEP 9CF
to deenergize. K11 is now set to be turned OFF when the next MS3A pulse
occurs. This is similar to STEP 13CH
The copyboard advances across MS9 and signals a change of copyboard drive
motion—clutch C.~2 is energized to drive the copyboard back to the normal
starting position. Capacitor C 16 is held by the change of voltage from D 16 to
STEP IOCF
D 17 (see STEP 11 CH
).
The paper begins to exit the copier. The timing of this step is the same as
STEP 11CF
STEP 15CH (last only).
SL7 is enabled for the purpose of jam detection. This is the same as
STEP 12CF
STEP 6CH (last only).
SL7 is disenabled as the jam detection period ends. This is the same as
STEP 13CF
STEP 17CH
(last only).
STEP 14CF
Due to machine timing, K 10 has remained deenergized since
STEP 9CF
Thus, the MS3A pulse acts to turn Kl 1 OFF. The jam detection circuit is
now deactivated in preparation for the standby condition or the next copy.
This is similar to STEP 19CH
© CANON INC. Second Printing-June, 1974