Epson EPL-N2700 Service Manual page 66

EPSON EPL-N2700 / N2750
(3) MP Cassette Paper Near Empty Sensor (PC5)
o
This sensor detects the paper near empty status of the MP Cassette
paper. The sensor uses a photointerrupter. As the sheets of paper
in the paper cassette decrease, the paper lifting plate in the paper
cassette lifts. When the paper lifting plate lifts exceeding a certain
point, the MP Cassette paper near empty occurs.
Paper near empty detection accuracy: 50
When enough paper is present in the paper cassette:
n
The paper lifting plate is lowered. In this condition, the lower part
of the sensor arm is engaged with the photointerrupter. Thus,
the light from the LED of the photointerrupter is blocked by the
sensor arm and the photointerrupter turns OFF. As a result, the
output of the photointerrupter is "H".
When the remainder of paper decreases:
n
The upper part of the sensor arm is pressed by the paper lifting
plate and the lower part of the sensor arm comes off the
photointerrupter. Thus, the light from the LED passes in the
photointerrupter and the photointerrupter turns ON. As a result,
the output of the photointerrupter is "L".
MP Cassette Paper
Near Empty Sensor (PC5)
Paper Lifting Plate
Light is blocked:
Output = H
[Paper is present]
Figure 2-7. MP Cassette Paper Near Empty Sensor Mechanism
Operating Principles
± 30 sheets
Paper
Few Paper
Paper Lifting Plate
Light passes:
Output = L
[Paper near empty]
Printer Mechanism Operating Principles
Timing Roller Front Sensor (PC2)
o
This sensor detects that the paper is fed inside the printer. The
sensor uses a photointerrupter. The output of the sensor is used as
a reference for feeding paper inside the printer. This sensor will be
activated when paper is fed from any paper source.
No paper is fed:
n
The sensor arm is pressed by a spring and the end of the sensor
engages with the photointerrupter. As a result, the output of the
photointerrupter is "H".
Paper is fed to the Timing Roller Front Sensor:
n
The sensor arm is pushed by the paper and the end of the
sensor arm comes off the photointerrupter. As a result, the
output of the photointerrupter is "L".
Timing Roller Front Sensor (PC2)
Figure 2-8. Timing Roller Sensor Mechanism
4108s018
Paper
Light is blocked:
Light passes:
Output = H
Output = L
[No paper]
[Paper is present]
Revision B
4108s020
67