1. Re-Pick Up Motor Drive Circuit
Figure 3-424 is a block diagram of the re-pick
up motor (M25), and the circuit has the following
functions:
1 Controls the speed of the motor.
2 Turns ON and OFF the motor.
3 Keeps the motor on hold.
The re-pick up motor is a 4-phase stepping
motor.
The microprocessor (Q501) on the DC con-
troller PCB generates the re-pick up motor drive
signal (RPKUD) and two types of mode select sig-
nals.
The mode select signal is a combination of 2-
bit signals (‘0’ and ‘1’) and is used to represent
three speeds; i.e., high, medium, and low to suit
the selected reproduction ratio.
The motor driver circuit rotates the re-pick up
roller by controlling the output timing of the pulse
signals A,
, B, and
.
When the re-pick up roller is at rest, the home
position sensor (Q87) monitors the re-pick up
roller to find out whether it is at a specific position
each time it makes a single rotation; the output
timing of the pulse signals A,
, B, and
is kept
to a specific timing and the power supply is
switched to +5 V to keep the re-pick up motor.
Table 3-405
B
A
B
A
3. OPERATIONS AND TIMING
COPYRIGHT © 1996 CANON INC.
CANON NP6085 REV.0 JULY 1996 PRINTED IN JAPAN (IMPRIME AU JAPON)
3-109
M25
Motor driver
circuit
Microprocessor
(Q501)
+38VU/+5VU
DC controller PCB
A
A
B
B
Q87
Re-pick up roller home position
detection signal
(RPKUHPD)
(RPKUD)
MODE1
MODE2
COM A
COM B
Figure 3-424
MODE1
0
1
1
0
Re-pick up
motor drive
signal
0
1
1
MODE1
0
1
0
0
Operation
Stop
High speed
Medium speed
Low speed
Mode select signal
