Epson Stylus Pro 9500 Service Manual page 50

EPSON Stylus Pro 9500
PAPER WIDTH DETECTION SENSOR
This sensor is mounted on the sub-carriage and detects the paper's left and
right edge positions, identifying the paper width and judging if the paper is
skewed.
If it recognizes that there is paper present, its output voltage is raised and if it
recognizes that there is no paper present, its output voltage drops.
Table 2-3. Paper Width Detection Sensor Detection Modes
Paper
Present
Not Present
Paper Right
Edge Detection
HP Side Reverse HP Side
Reverse HP
Side Scanning
Paper
Figure 2-7. Carriage Unit Paper Width Detection Sensor
A reflective type photosensor is used and the paper edge (paper present or
not) is judged by the 10-bit A/D converted value output by the sensor.
Detection of paper skew occurs in the following case and causes the message
"Set the paper correctly." to be displayed in the LCD.
n
If the front edge and back edge of a cut sheet are skewed more than 3
mm left to right.
Operating Principles
Output Voltage
Voltage rises.
Voltage drops.
Paper Width Detection Sensor
Carriage
Paper Left
Edge Detection
HP Side
Scanning
HP Side
Component List & Illustrations
Revision A
50