Canon EF-9, Service Manual

Page: 19 / 54

II. PICK-UP/FEED SYSTEM
A. Pick-up/Feed System
Figure 2-2-1
The envelope feeder pick-up motor (SMT11) is a stepping motor that is rotated clockwise and
counterclockwise by the envelope feeder driver PCB.
When the motor rotates clockwise, all rollers in the envelope feeder are rotated. When it
rotates counterclockwise, only the upper separation roller and feed rollers are rotated.
The envelope feeder driver PCB rotates the pick-up motor clockwise for about 1.0 second
when it receives the 1st Start command from the DC controller. After 0.1 seconds, the motor is
rotated counterclockwise for about 1.9 seconds. This process picks up and feeds the envelope
into the printer.
The envelope is stopped when it is 16mm past the registration paper sensor (PS1). Following
this, the envelope feeder driver PCB rotates the pick-up motor counterclockwise for about 1 sec-
ond in response to the 2nd Start command sent from the DC controller to feed the envelope
2 - 3
CHAPTER 2
PS1
Transfer charging roller
Photosensitive drum
PS931
SMT11
Envelope feeder driver PCB DC controller PCB
Serial line
SMT11: Envelope feeder pick-up motor
PS931: Envelope feeder paper sensor
PS1: Registration paper sensor (prinetr)
Envelope feeder
separation upper roller
Envelope
feeder pick-up
roller
Envelope feeder
feed roller
Envelope feeder
Torque
limiter
Envelope feeder
separation lower roller
Registration roller
➀
: ENVELOPE FEEDER PAPER SENSOR signal
➁
: ENVELOPE FEEDER PICK-UP MOTOR DRIVE signals
➀ ➁