Epson C11C605001 - DFX 9000 B/W Dot-matrix Printer Service Manual page 61

Service Manual
The paper stacked in the paper cassette is pushed by the feed rolls. This causes the top of the paper
stack to contact them. The feed solenoid comects or disconnect the main motor drive to the feed
roll assembly. When the feed solenoid is on and the feed rolls rotate, the top sheet of paper is
separated from the others and transported to turn rolls by friction separation.
The turn rolls send the paper supplied at the paper pick-up section (feed rolls) toward the
registration section (REGI. roll assembly and REGI. sensor). The turn solenoid connects or
disconnects the main motor drive to the turn roll assembly. While the turn solenoid is on and the
turn rolls stop, paper waits before the registration section. This causes through-put up. This printer
is long between paper pick-up position and registration section. If paper pick-up is started by the
trigger of the START (print start) signal, the video controller waits at paper feeding time. This
timing chart is Figure 2-16.
I
Video l/F Signal
Paper Position
Video Controller Job
Total Job Time
This printer fed paper until before registration section before receiving the START signal of engine
controller (MC PWB) so that through put up. This printer add PRFD (Pre Feed) signal of video
interface.
When the video controller sends PRFD (Pre Feed) signal of video interface signals to engine
controller (MC PWB) before START (print start) signal of video interface signals, this printer sends
paper to before REGI. sensor sensed position, and holds the sending paper on this position by turn
solenoid on. Then printer starts sending paper and printing when the engine controller (MC PWB)
receives START signal. The video controller process printing image between PRFD signal and
START signal sending. This timing chart is Figure 2-17.
The PRFD signal used sequence is through put better than no used sequence.
Video l/F Signal
Video Controller Job
Total Job Time
Rev. A
Image processing
Figure 2-16. Printing Timing Chart (1)
Wait position
Feed
Image processing
Figure 2-17. Printing Timing Chart (2)
Operating Principles
Feed Rolls REGI. Roll
Exit
Fuser
Drum
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