Purge Unit Paper Feed Motor Drive Switching Function; Purge Unit Structure And Functions - Canon BJC-3000 Service Manual

BJC-3000

1.2.2 Purge unit paper feed motor drive switching function

The paper feed motor drive switching function performs the switching of the paper
feed motor's drive power to drive the auto sheet feeder or the purge unit.

1.2.3 Purge unit structure and functions

a) Paper feed motor drive switching unit
The paper feed motor drive switching unit uses the slide arm, which is moved and
controlled by the positioning of the carriage, to perform the switching of drive power
from the drive input gear to drive the auto sheet feeder (ASF) or the purge unit.
For auto sheet feeder drive, the slide arm moves to the right, moving the ASF drive
switching flag into the ASF drive position where, with rotation of the paper feed
section in the reverse direction, paper pick up operations commence. The slide arm
will then move the ASF drive switching flag into the neutral position, and the
rotation of the ASF drive gear stops automatically as the pick-up motion is
completed.
For purge unit operation, the slide arm is moved further right than during auto
sheet feeder operation. Operations described below will be executed according to the
direction in which the paper feed roller rotates:
· Direction of paper feed:
· Reverse direction of paper feed:
b) Capping unit
Two caps are provided for use according to the type of BJ cartridge installed in the
carriage. Facing the purge unit, the left cap is for the Color/Photo BJ cartridges and
the right cap is for the Black BJ cartridge.
The capping unit is connected to a pump unit in the purge unit. The capping unit
uses the pump unit to suck ink from the head during cleaning operations. One
pump unit is responsible for ink suction for both types of cartridges, separately.
When the Color/Photo BJ cartridge is being used, the purge drive gear will rotate
counterclockwise as shown in
rotates in the reverse direction.
The ink which has been sucked out is sent to the waste ink absorber through the
pump unit. After suction is completed, the carriage is moved to a position where a
small gap between the cap and the head is created, and pumping operations to suck
the waste ink from within the cap are conducted.
Capping Unit
For Color/Photo BJ Cartridge
Drive Input Gear
Wiper Unit
Wiper-release Unit
Wiper Flag
Figure 5-4 Purge Unit Structure
Figure 5-4 ; when the Black BJ cartridge is used, it
For Black BJ Cartridge
ASF Drive Gear
ASF Drive Switching Flag
(ASF Drive Side)
(Neutral Side)
Slide Arm
Purge Drive Gear
(sucks black cap)
(sucks color/photo cap)
the purge drive gear rotates counterclockwise for
suction on the Color/Photo BJ cartridge cap
side.
the purge drive gear rotates clockwise for
suction on the Black BJ cartridge cap side.
5-5
Part 5: Appendix