Epson 680Pro - LQ B/W Dot-matrix Printer Service Manual page 39

EPSON Stylus COLOR 680/777/77i
2.1.6.2 Capping Mechanism
The capping mechanism covers the printheads with the cap holder to prevent the nozzle
from increasing viscosity when the printer is in stand-by mode or when the printer is
off. This product has valveless cap system. Air valve function used for the previous
models pumps and ejects ink only inside the cap by absorbing ink with the valve open.
By opening the Air valve, the negative pressure is decreased and only the ink inside the
cap is ejected. (the ink is not absorbed from Ink cartridge or head cavity.)
But, valveless cap system, this operation is done out side of the capping area.
The CR moves to left side of the Cap assembly and the pump absorbs the ink inside the
cap.
Viewed from front side
Slider cap
Printhead
Cap
Waste Ink tube
Figure 2-14. Cap Mechanism
Operating Principles
CR unit
Slide up
Overview
Revision B
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