Basic Operation; Manual Paper Feed Operation - Sharp SF-2050 Service Manual

3. Basic operation

(1) Manual paper feed operation

1 When the manual feed is at rest, the manual paper feed solenoid
(MPFS) is off and the manual feed stopper is closed with the
takeup roller in the up position. Latches and clutches are in the
position shown in the figure below.
Manual feed stopper
Manual feed
takeup roller
Transfer paper
Manual feed
spring clutch A
Manual feed latch A
2 When the PRINT switch is pressed, the manual paper feed
solenoid (MPFS) turns active, the manual feed latch B disengages
from the manual spring clutch B, and the manual feed roller and
the manual feed takeup roller start rotating. Then the manual feed
stopper is opened by the eccentric cam inside the spring clutch A,
and the manual feed takeup roller comes in close contact with the
copy paper to start paper feed.
Manual feed stopper
Manual feed
takeup roller
A
C
B
ON
Manual paper feed roller
Manual feed
friction plate
Manual feed
C
spring clutch B
A B
Manual feed
latch B
Manual feed
solenoid
Manual paper feed roller
3 When the pawl C of the manual feed spring clutch A is caught by
the manual feed latch, the manual feed stopper goes down by the
eccentric cam inside the spring clutch and the manual feed takeup
roller goes up by the eccentric cam outside the spring clutch. At
this moment, the transport roller is rotating.
Transfer paper
Manual feed
spring clutch B
Manual feed latch A
ON
4 The manual feed solenoid turns off after about 0.2 sec from when
the lead edge of the transfer paper is detected. At this time, pawl
B of manual feed spring clutch sleeve A is caught by manual feed
latch A.
Manual feed takeup roller
Transfer paper
Manual feed spring clutch A
A
Manual feed latch A
5 In synchronization with rotation of the transport roller, the manual
feed solenoid turns on for 0.08 seconds and the manual paper
feed roller rotates. A misfeed caused by a lack of seizure of the
transport roller is prevented. Here, the manual takeup roller is up.
Manual feed takeup roller
Transfer paper
Manual feed spring clutch A
A
Manual feed latch A
ON
8 – 2
Manual feed takeup roller
Manual feed stopper
Manual paper
feed roller
Manual feed
spring clutch A
A
Manual feed
B
latch B
Manual feed
solenoid
Manual feed stopper
Transport roller
Manual paper
feed roller
Manual feed spring clutch B
Manual feed latch B
C
B
OFF
Manual feed solenoid
Manual feed stopper
Transport roller
Manual paper feed roller
Manual feed spring clutch B
B
Manual feed latch B
Manual feed solenoid