Canon NP-70 Service Manual page 74

3-34
NP•70
As we can see, prestart for the first feed interval overlaps with warm-up time. This is due to
the fact that the delay hold for relay K7, which must be ON before copying can start, does
not come ON until 19.9 seconds after the power switch is turned ON.
3.311 FIRST FEED INTERVAL
"The period from the end of warm-up time (21.7 seconds) to the completion of C 16 discharge
(25.0 seconds)" is designated the First Feed Interval. During this period of 3.3 seconds, the
copier is in a condition in which copying operation is possible in one of the following two
ways:
1)
If the COPY switch was depressed before the start of the first feed interval, copying operation
will begin at the start of the first feed interval.
2)
If the COPY switch is depressed during the first feed interval, copying operations will begin at
the next MS1A pulse rather than proceed to neutral time. In this second case, the time for
the start of copy operations will be 25.7 seconds after power switch turn-on.
3.3-5 PRESTART TIME
As distinguished from prestart for the first feed interval, Prestart Time is designated as "the
interval from the depressing of the COPY button to the start of copying operations". The
dur ation of this time is 4.9 seconds and is determined by the charge time of C13 (0.2 seconds)
and 1.17 revolutions of the drum. This time will be constant in either half-size or full-size cop
copy cycles (see flowchart\ C~NI'~ to
3.3-6
COPYING CYCLE
STEP 4C
The portion of the copying operation during which copy/copies are made is designated the
Copying Cycle. This period may be defined as "the interval of time between Prestart Time
and the start of discharging of capacitor C16". As the period of time will differ according
to the paper size and the number of copies reproduced, the following points should be noted:
1)
For "half-size" copies, the time period is 3.6 seconds(see flowchart STEP 4C to
for the first copy. If more than one copy are being made, 4.0 seconds for each additional
copy will be added to the total copying operation.
2) For "full-size" copies, the time period is 6.6 seconds (see flowchart STEP 4C to
for the first copy. If more than one copy are being made, 8.0 seconds for each additional
copy will be added to the copying operation.
STEP 14CH
STEP 15CF
Second Printing,lune, 1974
© CANON INC.