Epson Stylus Color 640 Service Manual page 53

EPSON Stylus Color 440/640/740
2.1.1.6 Pump, Carriage Lock, Head Cleaner Mechanism
In the Stylus Color 440/640/740, there is no switch or mechanism to
change over the pump/paper feed mechanism. Therefore, whenever
the paper feed/pump motor rotate, pump drive roller in the pump unit
inside rotates. However, ink absorption/non ink absorption are
separated by the roller rotational direction. Also, even if the pump driver
rotates toward ink absorption and the carriage position is in the false
absorption position, only driving in the pump mechanism is performed
and actual ink attraction is not done. Figure 5-2 shows process of
conveying motive power to the pump drive roller.
See Figure 1-12. The process of conveying the motive power to the
paper eject roller by rotating the pinion of PF motor is descried in figure
2-10. This motive power is conveyed to the Gear C through the Gear B.
In the figure above, although the lever in order to drive Gear C, carriage
lock, head cleaner mechanism is shown separately, it is constructed as
one unit. Since the engagement of these two parts depends on the
tension of the compression spring, if the lever is burdened, only Gear C
and pump roller rotate and no more motive power is conveyed to the
lever part.
Chapter 2 Operating Principles
Axis of Paper
Gear A
Eject Roller
Gear B
Gear C
Compression
Spring
Actually, these parts
are one unit.
Pump Drive Roller
Figure 2-12. Pump Mechanism Power Transmission Process
Revision A
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