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AL-1457  OPERATIONAL DESCRIPTIONS  7 - 5

1) The figure below shows the positions of the pick-up roller, the

paper feed clutch sleeve, and the paper feed latch in the initial
state without pressing the COPY button after lighting the ready
lamp.
The paper feed latch is in contact with the projection of the clutch
sleeve.

2) When the COPY button is pressed, the main drive motor starts

rotating to drive each drive gear.
The pick-up drive gear also is driven at that time. Since, however,
the paper feed latch is in contact with the projection of the clutch
sleeve, rotation of the drive gear is not transmitted to the pick-up
roller, which does not rotate therefore.

3) After about 0.1 sec from when the main motor start rotating, the

tray paper feed solenoid (PFS) turns on for a moment.
This disengages the paper feed latch from the projection of the
clutch sleeve, transmitting rotation of the pick-up drive gear to the
paper feed roller shaft, rotating the pick-up roller to feed the paper.

4) After more than half rotation of the pick-up roller, the paper feed

latch is brought in contact with a notch on the clutch sleeve,
stopping rotation of the pick-up roller.

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.

OFF

PFS

OFF

RRS

OFF

PFS

OFF

RRS

ON

PFS

OFF

RRS

OFF

PFS

ON

RRS

AL-1457  OPERATIONAL DESCRIPTIONS  7 - 6

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.

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.

OF

MPFS

F

C

A

ON

MPFS

A

C

ON

MPFS

A

C

OF

MPFS

F

A

C

AL-1457  OPERATIONAL DESCRIPTIONS  7 - 7

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 micro-
switch (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-1225 as a stan-
dard provision, and it automatically copies up to 30 sheets of docu-
ments of a same size. (Only one set of copies)

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.

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

AL-1457  OPERATIONAL DESCRIPTIONS  7 - 8

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).

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