Upper Surface Sensor Mechanism; Paper Return Mechanism - Epson Stylus Pro 5000 Service Manual

Stylus Pro 5000

UPPER SURFACE SENSOR MECHANISM

As the number of sheets in the paper tray decreases, the paper stack
height is reduced. Unlike previous ink jet printer models, the lifter in the
Stylus Pro 5000 supports the hopper directly. If the lifter raised the
hopper by a fixed amount, paper loading would become less effective as
the paper stack height decreased. The upper surface sensor mechanism
prevents this.
Paper Load Roller
Upper Surface Sensor
Flag
Paper
Lifter
Hopper
Separation Pad
[Waiting Condition]
Figure 2-5. Upper Surface Sensor Mechanism
As shown in Figure 2-5, when the lifter is idle, the hopper in the paper
tray does not contact the paper load roller. After the printer receives a
printing command, the lifter rises and the hopper is pushed up. When the
flag attached to the paper feed roller lever reaches the upper surface
sensor (attached to the ASF frame), the main board stops the gear train,
and the lifter stops rising. The paper load roller is then at the proper
height to pick up the top sheet from the stack.
Flag is up
Lifter is up
[Paper Loading Condition]

PAPER RETURN MECHANISM

The purpose of the paper return mechanism is to return any extra sheets
picked up by the paper load roller to the paper tray. When the paper load
roller rotates, the mechanism raises the Paper Return Lever.
Second Paper
First Paper
Figure 2-6. Paper Return Lever Operation
When the printer receives a print command, the paper load roller rotates,
loading the top sheet from the paper stack (see Figure 2-6). Sometimes
the top sheet will be attached to the page below it with static electricity.
When two or more pages feed at once, there is usually a small distance
between the leading edge of the first sheet and the leading edge of the
second sheet.
When the leading edge of the first sheet reaches the point where the sub
roller and paper feed support roller meet, the paper return lever pushes
any subsequent pages back into the tray.
Chapter 2 Operating Principles
Sub Roller
PF Support Roller
Paper Return Lever
It pops out
at paper loading
Paper Load Roller in
waiting position
Separarion Pad
Paper Load Roller in loading
position
2-6