Epson WF-C5790 Service Manual page 63

EPSON WF-C5790/WF-C5790a/WF-C5710/ET-8700/WF-C5210/WF-C5290/WF-C5290a
OPERATION OF EACH MECHANISM
Pump Mechanism
The pump mechanism sucks ink from the printhead at cleaning.
The drive force from the Pump-drive Compound Gear is transmitted to the
pump shaft via the Timing Plate. This Timing Plate allows the Pump-drive
Compound Gear to start rotating at the different timing from the Pump Shaft.
After the PF Motor rotates for a while, the Pump Unit starts its operation.
When the Pump Motor rotates counter-clock wise as seen from the output-shaft
side of the motor, the drive force via the Pump-drive Compound Gear rotates
the Pump Pulley to flatten the tube to suck the air (to generate negative
pressure) inside the tube.
When the Pump Motor rotates clock wise, the Pump Pulley does not flatten the
tube, and the negative pressure is released.
Furthermore, this products incorporate two pumps, with improved suction
performance.
Pump motor counter-clock wise
rotation (suction)
Rotates flattening
the tube.
Figure 3-44. Pump Mechanism (1)
Configuration and operating principles
Pump motor clock wise
rotation (release)
Rotates without
flattening the
tube.
Operating principles
Pump Frame
Pump Tube
Pump Frame
Pump Tube
Pump Spring (x2)
Pump Pulley
Figure 3-45. Structure of the Pump Unit
Revision A
Pump Cam
Pump Pulley
Pump Shaft
Pump Spacer
Pump Shaft
Pump-drive
Compound Gear
Pump Cam
Timing Plate
Confidential
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