Epson Stylus CX3700 Service Manual page 48

EPSON Stylus CX3700/CX3800/CX3805/CX3810/DX3800/DX3850
2.2.5.2 Pump Unit Mechanism
The PF Motor also controls the Pump Unit mechanism (including the Change Lever) as
well as the Paper loading/feeding mechanism. The drive of the PF Motor is always
transmitted to the Pump Unit. (And also, its drive is transmitted to the LD Roller
through the Clutch mechanism & the Change Lever.)
On this printer, the Pump Unit mechanism including the Change Lever plays a major
role expecting the ink eject operation. And, these operations control depending on the
PF Motor rotational direction as the following table below.
Table 2-5. PF Motor rotational direction & Ink system mechanism
Directions *
Clockwise • Pump release
• Absorbs the ink
Counterclockwise
• Release the Change Lever from the Clutch mechanism
Note "*": The PF Motor rotational direction = seen from the left side of the printer.
Left side view
Spur Gear 30.8
PF Motor Spur Gear 32.4
pinion gear (PF Roller)
Transmission Path: PF Motor pinion gear (CW) → Spur Gear 30.8 (CCW) → Spur Gear 32.4 (PF Roller) (CW) → Spur gear 13.5 (PF Roller) (CW) →
Combination Gear 21.24 (CCW) → Spur Gear 27.2 (Pump Unit gear) (CW)
(Above transmission pass = seen from the right side of the printer)
OPERATING PRINCIPLES
Functions
Figure 2-12. PF Motor drive transmission path to the Pump Unit
Printer Mechanism
1. Ink eject operation (usual operation)
The ink is absorbed from the Ink Cartridge, the ink cavity and is ejected to the
Waste Ink Pad from the Cap when the Ink Tube is pressed by a roller in the Pump
Unit.
Following figure shows you the overview of the Pump Unit mechanism operation.
Cap Unit
side
Note : The PF Motor rotational direction = seen from the right side of the printer.
Figure 2-11. Pump mechanism
Pump Unit
Spur Gear 27.2
(Pump Unit gear)
Spur Gear 13.5
Cap Unit
(PF roller)
Revision A
Waste Ink
Pad side
Right side view
Combination
Gear 21.24
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