Controlling The Pickup Motor; Motor - Canon NP6512 Service Manual

CHAPTER 8 ADF
G.

Controlling the Pickup Motor

1. Outline
Figure 8-121 is a diagram of the control circuit for the pickup motor (M2).
The pickup motor is a DC motor.
The CPU (Q1) on the ADF controller PCB sends the motor drive signals PM0 and PM1 to the
motor driver (Q5). The pickup motor rotates clockwise or counterclockwise according to the com-
binations of the states of these two signals. (Table 8-102 shows how the pickup motor rotates for
each combination.)
The motor driver is equipped with a limiter function, preventing overcurrent from flowing into
the motor. When an overcurrent occurs, the limiter function cuts off the motor drive current,
thereby preventing damage to the motor.
When the limiter function is activated, the pickup motor cannot rotate as controlled, possibly
leading to pickup faults. Any pickup fault causes the ADF controller to flash the JAM indicator on
the copier and stop the pickup motor at the same time.
Q1
CPU
8-14
COPYRIGHT © 1999 CANON INC.
ADF controller PCB
PM1
PM0
Figure 8-121
Motor drive Motor drive
signal (PM0) signal (PM1)
'1'
'1'
'0'
'0'
Table 8-102
CANON NP6512/6612/7120/7130/7130F REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
+24V
Q5
PMRD1

Motor

driver
PMRD1*
Pickup roller
rotation
'1' Braked
'0' Picking up
'1' Delivering
'0' At reset (free)
Pickup
motor
M2