Chapter 3. Mechanism Blocks; General Description - Sharp FO-1850 Service Manual

FO-1850TH

CHAPTER 3. MECHANISM BLOCKS

[1] General description

1. Document feed block and diagram
Separation
rubber
Separate
plate
Separate
spring
Feed roller 2
Document
sensor lever
Pinch roller
spring 1
Pinch roller 2
Pinch roller
spring 2
2. Document feed operation
1) The original, which is set in the document hopper, feeds automati-
cally when the front sensor is activated. This is turn activates the
pulse motor which drives the document supply roller. The docu-
ment stops when the lead edge is detected by the document
sensor.
2) The lead edge of the original is fed a specified number of pulses
after the lead edge of the document is detected for the reading
process to begin.
3) The trailing edge of the original is fed a specific number of pulses
after the trailing edge of the document deactivates the document
sensor. The read process then stops and the original is dis-
charged.
4) When the front sensor is in the OFF state (any document is not
set up in the hopper guide), the drive will be stopped when the
document is discharged.
3. Hopper mechanism
3-1. General view
The hopper section contains document guides that are used to adjust
the hopper to the width of the original document. This ensures that
the original feeds straight into the fax machine for scanning.
Document width: 148 mm to 216 mm (A5 longitudinal size to Letter
longitudinal size)
NOTE: Adjust the document guide after setting up the document.
Hopper guide
Document guide,
upper
Document guide,
lower
Paper feed spring
Front sensor
Paper feed roller
Pinch roller
Fig. 1
Fig. 2
3-2. Automatic document feed
1) Use of the paper feed roller and separation rubber plate ensures
error-free transport and separation of documents. The plate spring
presses the document to the paper feed roller to assure smooth
feeding of the document.
2) Document separation method: Separation rubber plate
3-3. Documents applicable for automatic feed
Feeder capacity
Paper weight
Paper thickness (ref.)
Paper size
NOTE: Double-side coated documents and documents on facsimile
recording paper should be inserted manually. The document
feed quantity may be changed according to the document
thickness.
Documents corresponding to a paper weight heavier than 64.3kg
2
(74.3g/m ) and lighter than 135kg (157g/m
ual feed.
Documents heavier than 135kg in terms of the paper weight must be
duplicated on a copier to make it operative in the facsimile.
3-4. Loading the documents
1) Make sure that the documents are of suitable size and thickness,
and free from creases, folds, curls, wet glue, wet ink, clips, staples
and pins.
2) Place documents face down in the hopper.
i) Adjust the document guides to the document size.
ii) Align the top edge of documents and gently place them into
the hopper. The first page under the stack will be taken up by
the feed roller to get ready for transmission.
NOTES: 1) Curled edge of documents, if any, must be straighten
out.
2) Do not load the documents of different sizes and/or
thicknesses together.
3 – 1
Separation rubber
Paper feed spring
Paper feed roller
Fig. 3
4x6 series Square
(788mm x 1091mm x meter series
1000mm sheets)
Minimum Maximum Minimum
20 sheets, max.
45kg 64.3kg 52g/m
0.06mm 0.09mm 0.06mm
B6 (128mm x 182mm) ∼
A4 (210mm x 297mm), Letter (216mm x 279mm)
2
) are acceptable for man-
Maximum
2 2
74.3g/m
0.09mm