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AL-1551 OPERATIONAL DESCRIPTIONS 7-6

5) At this time, the paper is fed passed the paper entry detection switch

(PPD1), and detected by it. After about 0.15 sec from detection of

paper by PPD1, the tray paper feed solenoid (PFS) turns on so that

the clutch sleeve projection comes into contact with the paper feed
latch to stop the pick-up roller. Then the pick-up roller rotates for

about 0.15 sec so that the lead edge of the paper is evenly pressed

on the resist roller, preventing against skew feeding.

6) To release the resist roller, the tray paper feed solenoid and the resist

solenoid are turned on by the paper start signal to disengage the

resist start latch from the clutch sleeve, transmitting rotation of the

resist drive gear to the resist roller shaft. Thus the paper is
transported by the resist roller.

7) After the resist roller starts rotating, the paper is passed through the

pre-transfer guide to the transfer section. Images are transferred on
the paper, which is separated from the OPC drum by the drum curve

and the separation section.

8) The paper separated from the drum is passed through the fusing

paper guide, the heat roller (fusing section), POD (paper out

detector) to the copy tray.

1) Before paper feed operation, the manual paper feed solenoid

(MPFS) is turned OFF as shown in the figure below.

2) When the PRINT button is pressed, the manual paper feed solenoid

(MPFS) turns on to disengage the manual paper feed latch.

A from the manual paper feed clutch sleeve A, rotating the manual

paper feed roller and the manual take-up roller. At the same time, the
manual paper feed stopper opens and the manual take-up roller is

pressed to the surface of the paper to start paper feeding.

ON

PFS

OFF

RRS

OFF

PFS

ON

RRS

OF

MPFS

F

C

A

ON

MPFS

A

C

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AL-1551 OPERATIONAL DESCRIPTIONS 7-7

3) When pawl C of the manual paper feed clutch sleeve is engaged with

the manual feed latch, the manual feed stopper falls and the manual

take-up roller rises. At that time, the manual paper feed roller is

rotating.

4) The lead edge of the transported paper is pressed on the resist roller

by the transport roller. Then the paper is stopped temporarily to allow

synchronization with the lead edge of the image on the OPC drum.

From this point, the operation is the same as the paper feed
operation from the tray. (Refer to A-5 - 8.)

5) The solenoid turns off to close the gate and return to the initial state.

ON

MPFS

A

C

a

PPD1 jam

PPD1 does not turn off within 4 sec after turning 
on the resist roller.

b

PPD2 jam

PPD2 is off immediately after turning on the 
resist roller.
PPD2 does not turn off within 1.2 sec after 
turning off the resist roller.

c

POD jam 

POD does not turn on within 2.9 sec after turning 
on the resist roller.
POD does not turn off within 1.5 sec - 2.7 sec 
after turning off PPD2.

OF

MPFS

F

A

C

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AL-1551 OPERATIONAL DESCRIPTIONS 7-8

1) When the power is turned on, the detection gear 38T is rotated in the

arrow direction by the detection gear 20T to push the microswitch
(process detection switch) installed to the machine sensor cover,

making a judgement as a new drum.

2) When the detection gear 38T turns one rotation, there is no gear any

more and it stops.

The latch section of the 38T gear is latched and fixed with the

projection of the process cover.

The SPF (Single Path Feeder) is installed to the AL-1451 as a standard

provision, and it automatically copies up to 30 sheets of documents of a

same size. (Only one set of copies)

Gear 20T

Process detection switch

Gear 38T

(1)

Pickup roller

(2)

Sheet of document 
for paper feed

(3)

Set detection ACT

(4)

Paper stopper

(5)

Document feed roller

(6)

Separation sheet

(7)

Paper entry sensor

(8)

PS roller D

(9)

Transport follower roller

(10)

Paper exit roller

(11)

Paper exit follower roller

(12)

Document tray

Gear notch

Gear pawl

Projection

Gear notch

Gear pawl

Projection

(2)

(1)

(3)

(4) (5)

(6)

(7)

(8)

(9)

(10)

(11)

(12)

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AL-1551 OPERATIONAL DESCRIPTIONS 7-9

1) When SPPD is ON (document remaining) when the power is turned

on.

2) When SPPD is not turned ON within about 1.5 sec (at 100% copy)

after starting the document feed operation.

3) When SPPD is not turned on within about 4.7 sec (at 100% copy)

after turning on SPPD.

4) When the SPF document jam release door or the OC cover is

opened during document transport (SPF motor rotating).

Set duplex documents on the document tray.
Set paper on the cassette. (In the duplex mode, the manual feed tray

cannot be selected.)

The document feed roller feeds the document from the paper feed roller

to the PS roller.

• The document is exposed in the exposure section, and sent to the

document exit section

• by the transport/paper exit roller.

• R-SPF gate solenoid ON

• The document is sent to the intermediate tray.

(but not discharged completely.)

• The document is stopped once, then switchback operation is

performed. 

(To the back copy)

The document is passed through the paper feed roller and the PS roller

by the paper feed roller

and the images on the front surface are transferred.

• The paper is passed through the fusing section and the lower side of

the gate section to the paper exit tray side, (but not discharged
completely.)

• It is stopped once and switchback operation is performed. 

(To the back copy)

SPID ON

PSW ON

MIRM rotation

MM rotation

CPFS ON

SPFM rotation

SPUS ON

Document set

Document set sensor

Document feed unit lamp ON

PPD ON

RRC ON

SPPD ON

POD ON

Copy start

The scanner is shifted
to the exposure position.

(Copier side)

Main motor rotation

Paper feed

Synchronization

(Transfer)

(Fusing)

(Document exit)

Paper transport

(Exposure)

In the zooming mode, the magnification ratio in the sub 
scanning direction (paper transport direction) is adjusted
by changing the document transport speed.

(Paper exit)

SPF motor rotation

Document feed

Document transport sensor

Document transport

(SPF side)

Time chart (Tray feed)

752msec

625msec

756msec

PSW

MIRR M

SPF M

CL

SPUS
SPPD

SCANST

MAIN M

CPFS1

RRS
PPD1

PPD2

POD

Gate OFF

Lower Side of Gate

Gate ON

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