AR-M351U, AR-M451U (serv.man14). Maintenance details of following sections, 5-Laser Scanner, 6-Scanner, 7-DSPF, 8-Operation Panel - Sharp Copying Equipment Service Manual (repair manual). Page 14

AR-M351U/M451U, AR-M355U/M455U  MAINTENANCE AND DETAILS OF EACH SECTION  7 - 56

The document fed by the take-up roller is sent through the paper
feed roller and the transport roller to the resist roller section.

In the resist roller section, the document lead edge and the scan
start position are synchronized. The document is transported to
the scan section. After being scanned, the document discharged
to the document exit tray by the paper exit roller.

The document transport speed varies depending on the scan
mode and the scan magnification ratio as shown below. 

1

2

5

7

8

10

12

3

4

6

9

11

Code

Signal 

name

Name

Function/Operation

Type

Note

SCOV

SCOV

SPF cover switch

SPF cover open/close detection

Transmission type

Sensor

SPFM

SPFM1

SPF paper feed motor, paper 
transport motor

Drives the paper feed roller and the 
transport roller. (SPF)

Stepping motor

SPFC

SPFC

SPF paper feed clutch

SPF paper feed section roller ON/OFF 
control

Electromagnetic clutch

SRRC

SRRC

SPF resist roller clutch

SPF resist roller ON/OFF control

Electromagnetic clutch

SPED

SPED

SPF document set detector

SPF document presence detection

Transmission type

Sensor

SPPD

SPPD

SPF document paper pass detector SPF document paper pass detection 1

Transmission type

Sensor

SPFS

SPFS

SPF document pickup solenoid

SPF document pickup

Solenoid

STMP

STMP

FAX finish stamp solenoid

Drives the FAX document finish stamp.

Solenoid

SPLS1

SPLS1

SPF document length detector 1

SPF document length detection (Short)

Transmission type

Sensor

SPLS2

SPLS2

SPF document length detector 2

SPF document length detection (Long)

Transmission type

Sensor

SPFVR

SPFVR

SPF document size (Width) 
detection analog data detector

SPF document size (Width) detection

Volume resistor

Other 
detector

SOCD

SOCD

SPF open/close detector

SPF unit open/close detection

Transmission type

Sensor

SPOD

SPOD

SPF paper exit detector

SPF paper exit detection

Transmission type

Sensor

No.

Name

Function

1

CIS unit
 (AR-EF3 only)

This is an image sensor unit to scan the back of a document. An image sensor (CIS: Contact 
Image Sensor) of 7,196 pixels is employed. The scan resolution is 600dppi.LED lights in the 
unit are reflected onto the document. Lights reflected from the document are passed through 
the lens to form images on the photoelectric conversion elements. 
The photo energy is converted into electric energy.

2

Document resist roller

This roller makes synchronization between the document lead edge and the scan start 
position.

3

Document resist front sensor 
(SPPD)

Detects that a document reaches the resist roller. 

4

Document set sensor

Detects that a document is set on the tray.

5

Document feed roller

Feeds documents. 

6

Separation plate

The rubber plate prevents against duplicated feed of documents.

7

Document length sensor 
(SPLS1/SPLS2)

Detects the document length to detect the document size.

8

Document width detection volume

Detects the document width to detect the document guide. 

9

SPF motor

Transports a document in the SPF.

10

Document take-up roller 

Picks up a document and transport it to the document feed roller.  

11

Document exit roller

Discharges a document.

12

Document exit sensor (SPOD)

Detects document exit. 

Scan mode

Magnification ratio

Document 

transport speed

Single surface scan/
Duplex scan

100% or above

220mm/sec

Single surface scan/
Duplex scan

101% or above

110mm/sec

High image quality 

110mm/sec

FAX

167.1mm/sec