Samsung ML-2015/XEV Service Manual page 28

System Overview
3.2.4 Sensor Controller
3.2.4.1 Paper Feeding/Width
When a paper passes an actuator of a feed sensor unit after feeding a paper into a set,it detects a signal of
the photo interrupter and informs the paper feeding status to CPU. After sensing the signal and certain time
later, it strews an image data.(Related in Paper Front Edge Adjustment)
If it could not detect the feed sensor within 1 second after feeding a paper, a paper jam0 (CPU#_) occurs.
ML-1610 differs from other general printers because it doesn't have a paper empty sensor. It recognizes
the paper existing status by using a firmware. If a paper is not fed, it recognizes the state as no paper (Red
and Yellow lights turn on among other LEDs). With the same principle, it senses the OPC unit. After OPC
unit is mounted,the actuator operates. When it passes the actuator of sensor unit, it detects the signal of
the photo interrupter, informs the existing OPC unit to CPU, and then stays at the status.
3.2.4.2 Paper Empty Sensing
The paper empty is detected by the empty sensor mounted to an engine board and the actuator mounted
to a frame. Paper senses the on/off time of the empty sensor by using CPU and informs the normal
operation status and the jam occurrence status to CPU.
3.2.4.3 Jam Cover/Cover Open Sensing
ML-1610 uses two M/S:one senses the cover open and the other senses the jam cover open.
The cover open sensor is located on the left bottom of HVPS.When the front cover is open, +24V supplied
to each unit (DC fan,Solenoid,Main Motor,Polygon Motor Unit of LSU in Fusing Unit,and HVPS)is
interrupted.
The jam cover open sensor is located on the left bottom of SMPS. When the jam cover is open, +24V
supplied to each unit (DC fan, Solenoid, Main Motor, Polygon Motor Unit of LSU in Fusing Unit, and HVPS)
is interrupted.
D0 bit of CPU detects the jam cover open/cover open, and D7 bit of CPU detects the existence of OPC.
In this case, it informs the status to user by turning on the red LED among OP panel LEDs.
3.2.4.4 Solenoid Driving Circuit
The solenoid consists of two used for paper pick-up and MP signal. D4 bit of CPU turns it on/off, and its
driving time is 300ms. The diode protects the drive TR from the pulse (noise)generated by de-energizing
operation of solenoid.
Service Manual
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