Epson Stylus Pro 9500 Service Manual page 51

EPSON Stylus Pro 9500
PG SETTING MECHANISM
In order to maintain the distance between the print head nozzle surface and the
paper constant in correspondence with the thickness of the paper used, a
mechanism is incorporated into this printer's carriage which enables the print
head position to be set in 3 stages in the height direction as viewed from the
paper surface. The PG home position is detected by the LID home position
detection sensor mounted on the right frame and the SLID gear.
A reflective type photosensor is used in the SLID home position detection
sensor, and this detects the position of the notch in the SLID gear and make
that the home position.
The mechanism is configured so that when the sub-carriage is in the lowest
position, the sensor's output is "OFF," and the point when, during the detection
operation, the head drops down from its position after rising up, and the
sensor's output changes from "ON" to "OFF," is recognized as the mechanical
PG home position (PG = small).
Changes in the PG value from the PG home position are implemented by the
following operation
o
PG home position SLID motor pinion gear rotates CCW (Note)
gear SLID gear shaft rotates CCW
Sub-carriage modes up (PG becomes wider).
Note): CCW rotation is the rotational direction shown if you are looking from
the printer's right side.
The SLID eccentric cam is eccentric in 3 stages and the following 3 stages of
PG value setting are enabled by the number of SLID motor CCW rotation steps
in the above operation.
Table 2-4. SLID Home Position Detection Sensor Detection Mode
Slide Gear Notch
PG Value
Position
Down
Small (1.4 mm)
(Left figure right)
Medium (2.3 mm) Right
Large (2.8 mm) Up (Left figure left)
Operating Principles
SLID
SLID eccentric cam rotates CCW
Sensor Output Output Voltage
OFF 2.0 V or lower
ON 2.0 V or lower
ON 3.0 V or higher
Component List & Illustrations
SLID eccentric
cam
Print head
Slide Gear
Sub CR unit
Figure 2-8. SLID Home Position Detection Sensor (PG Home
Position Detection Sensor)
Also, the actual PG value during printing is one of the following setting values
determined by the combination of the panel setting (Auto;, Widen), command
setting (default PG/PG large), and paper thickness detection sensor (thick
paper/thin paper) (Note).
Table 2-5. PG Position - Panel Setting / Paper Thickness
Panel PG Setting Command Setting
PG Large
Widen
Default PG
PG Large
Auto
Default PG
Note): See concerning the paper feed mechanism about the paper thickness
detection sensor.
Revision A
Paper Thickness
PG Position
Detection Sensor
Thick Paper PG Large
Thin Paper PG Large
Thick Paper PG Large
PG Medium
Thin Paper
Thick Paper PG Large
Thin Paper PG Large
Thick Paper PG Large
PG Small
Thin Paper
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