Fusing Loop Control - Epson AcuLaser C1900 Service Manual

EPSON AcuLaser C1900/AcuLaser C900

2.4.6.2 Fusing Loop Control

To maintain a posture of paper when it is located just before entering the fusing unit as well
as to prevent possible image quality defects caused by a rotational speed fluctuation of
fusing roller, the following mechanism is built into the ptiner engine.
FUSING LOOP SOLENOID (SL6)
The fusing unit is driven by a main motor; M1, and due to a variation of roller parts and a
changes with a hardness of fusing roller rubber, certain level of rotational speed fluctuation
is occur. In order to minimize an effect of speed fluctuation, a variable rotational speed
control mechanism is built in the engine and a rotational speed is switched by the Fusing
loop solenoid (SL6). The fusing loop sensor (PC11) monitors a level of loop which formed
with a paper, and a speed control is made in accordance with the staus of this sensor.
FUSING LOOP SENSOR (PC11)
This sensor monitors a posture of paper at the position where the paper is located just before
entering the fusing unit.
The hardness of fusing roller which built in the fusing unit, is changed with time causing a
fluctuation of paper feeding speed within the unit, and this influence the image quality. To
avoid this, paper must keep an appropriate posture with it and a certain level of loop is
formed with a paper for this purpose. This sensor checks a condition of loop formed with a
paper and feedback to the variable speed control.
Operating Principles
Fusing Loop Solenoid (SL6)
Description of Mechanisms
Fusing Loop Sensor (PC11)
Figure 2-25. Fusing Loop Control Mechanism
Revision B
110