Paper-Feeding-Related Sensors - Epson Stylus PRO Color Large Format Inkjet Printer 7000 Service Manual

EPSON Stylus Pro 7000

PAPER-FEEDING-RELATED SENSORS

The following sensors aid in the paper feeding process.
P_FRONT sensor
This sensor is attached to the subplaten and is an optical (photo-
reflective) sensor. This sensor detects the front edge of the paper after
paper has been loaded but before it is set and ready to print.
P_REAR sensor
This sensor is attached to the Upper Paper Guide and is an optical
(photo-reflective) sensor. This sensor detects the rear edge of the
paper and detects the front edge when the paper is first loaded in the
paper path. The position of this sensor is stored in EEPROM.
P_EDGE sensor
This sensor is attached to the Cutter Housing section on the carriage
and detects the right and left edges of the paper. This sensor is also
used to check for paper skew by checking whether the edges are in
the same location at the top and bottom of a page.
P_THICK sensor
This optical sensor physically gauges whether the paper falls into the
normal/thin category or the thick category. For details, see "Platen
Gap Mechanism" on page 70.
Table 2-2. Paper Thickness Detection
Detected
Sensor Signal
Thickness
0.6mm or less On
0.7mm or more Off
Paper Set Lever sensor
The Paper Set Lever sensor is located on the right side of the printer,
and this optical sensor determines whether or not the Paper Set lever
is in the set (print) position.
Operating Principles
Output Signal
Strength
0.7V or more
2.4V or more
Description of Components
Note that the P-Thick and Paper Set Lever sensors as well as
their corresponding flags are located next to each other. The
sensors employ the two metal flags on top of the Secondary
Roller unit (second from the HP side when facing the
printer). The left flag is used to determine the paper
thickness and the right flag is used to determine the Paper
Release Lever position.
Double sensor and flag set:
R = Paper set lever sensor
L = P_Thick sensor
Paper feed
direction
Figure 2-12. Paper Feed Sensors
Revision B
P_Rear
sensor
Paper Set
lever
P_Front
sensor
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