AL-840 (serv.man3). AL800 840 Service Manual-Basic Manual - Sharp Copying Equipment Service Manual (repair manual). Page 8

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The main motor is a 4-phase stepping motor of 2-phase excite-
ment bipolar system, which serves as the drive source of the paper
feed and transport system. 

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The pickup solenoid operates on 24V and turns ON/OFF paper
feed operation.

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The following sensors are used.

It is installed on the LSU PWB and is used to detect whether there is
paper in the paper feed tray or not.

This sensor is used to detect the paper feed timing of next paper (in
pre-feed) and to make synchronization between paper transport and
image forming on the drum. It is also used to detect a paper jam.

This sensor is used to detect that paper is discharged.

It is also used to detect a paper jam.

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Paper release lever

The paper release lever is used to fix or release paper. To release
paper, pull the lever toward you as shown in the figure below. To fix
paper, push the lever forward. The lever mechanism is as shown
below.

PUS

MEN

ASIC

(IC8)

MCU(PCU)PWB

MMT0

MMT1

CPU

(IC5)

1
2

3
4

MA
MA-

MB
MB-

CN804

1
2

3

+5V
POUT

GND

+24V

CN805

1

2

+24V

PUS

PD801

+5V

PIN

PD802

+5V

POUT-

CN7

9

PE

CN9

PE

LSU PWB

+24V

9 PE

PD601

CN601

High voltage power PWB

Paper pickup
solenoid

Main motor

Paper feed
roller

Paper entry 
roller

Paper exit 
roller

Paper empty 
roller

Motor
driver

(Paper release)

(Paper fixed)

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