Canon BJ-W3000 Service Manual page 112

After the guide roller has rotated 160 de-
grees, it is stopped for about 2 seconds. The
waste ink carriage tube which was squeezed
recovers during this period, and suction is
generated, sucking ink from the color head
nozzles. The guide roller then rotates 223
degrees, where the cam for the black head
starts to squeeze the waste ink carriage tube.
After the guide roller has rotated 340
degrees, it is stopped for about 3 seconds,
while the waste ink carriage tube recovers,
sucking ink from the black head nozzles.
The guide roller then, rotates to the home
position.
When sucking only color ink, the black
ink cap is released, so that no black suction
occurs.
After printing is completed, the caps of all
the heads are released, and the guide roller is
rotated 4 times to move ink that has accumu-
lated in the waste ink carriage tube to the
waste ink absorber unit.
Guide
roller
Pressurizing
cam
(for black
ink)
Waste
M3
ink tank
Figure 2-405
Head
Cap
Carriage
tube
Pressurizing
70˚
cam
(for color ink)
40˚
Actuator
Purge position sensor
Purge motor
CHAPTER 2. BASIC OPERATION
c. Timing
[1] User cleaning 1
The user can perform the cleaning
operation for all heads.
• One suction operation occurs for all
heads.
[2] User cleaning 2
The user can perform the cleaning
operation for the Bk head.
• One suction operation occurs for the
Bk head.
[3] User cleaning 3
When an ink tank is removed and
then reinstalled, the user can perform
the cleaning operation for at head.
• Three suction operations occur for the
corresponding head.
[4] Suction for a replaced ink tank
When an ink tank is replaced, head
cleaning is conducted.
• Three suction operations occur for all
heads, color head, or the Bk head.
[5] Suction for replaced BJ print head
When a BJ print head is replaced, head
cleaning is conducted.
• Four suction operations occur for all
heads.
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