Ricoh VT1800 User manual

N810-II
SERVICE MANUAL

INTRODUCTION
This manual explains only the features of the N810-II (C225 model) that are
different compared with the N810 (C217 model). So, please refer to the N810
service manual for the sections which are not described in this manual.

SECTION 1
OVERALL MACHINE
INFORMATION

1. SPECIFICATIONS
Configuration: Desk top
Master Making Process: Digital
Printing Process: Full automatic one-drum stencil system
Image Mode: Line/Photo
Original Type: Sheet
Original Weight: 64 g/m2∼104.7 g/m2(17.0 lb ∼27.9 lb)
Original Size: Max: 216 mm x 356 mm (81/2" x 14")
(Legal Drum)
216 mm x 297 mm (81/2" x 11.7")
(A4 Drum)
Min: 90 mm x 140 mm (31/2" x 51/2")
Paper Size: Max: 216 mm x 356 mm (81/2" x 14")
(Legal Drum)
216 mm x 297 mm (81/2" x 11.7")
(A4 Drum)
Min: 90 mm x 140 mm (31/2" x 51/2")
Paper Weight: 52 g/m2∼150 g/m2(13.8 lb ∼39.9 lb)
Printing Area: LG drum: 210 mm x 349.6 mm
(8.3" x 13.8") or less
A4 drum: 210 mm x 291 mm
(8.3" x 11.5") or less
Printing Speed: 70/100/130 cpm (3 settings)
First Copy Time: 28 seconds ± 2 seconds (Legal Drum)
26 seconds ±2 seconds (A4 Drum)
Second Copy Time: 30 seconds ±2 seconds (Legal Drum)
28 seconds ±2 seconds (A4 Drum)
Leading Edge Margin: 5mm ±3 mm (0.2" ±0.12")
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Trailing Edge Margin: 1 mm ±1 mm (0.04" ±0.04")
Paper Feed Table Capacity: 500 sheets (80 g/m2, 20.0 lb)
Paper Delivery Table Capacity: 500 sheets (80 g/m2, 20.0 lb)
Master Eject Box Capacity: More than 25 masters
ADF Original Capacity: 6 sheets or a 0.6 mm height
Weight: 55 kg (122 lb)
Power Source: 120 V, 60 Hz, more than 3.6 A (for North
America)
220 V ∼240 V, 50/60 Hz, more than 2.1 A
(for Europe, Asia)
Power Consumption: Master Making: Less than 0.22 kW
Printing: Less than 0.22 kW
Dimensions:
(W x D x H) [Tables stored] 692 mm x 612 mm x 440 mm
(26.2" x 24.1" x 17.3")
[Tables set up]
1050 mm x 612 mm x 440 mm
(41.3" x 24.1" x 17.3")
Pixel Density: 300 dpi
Print Counter: 7 digits
Master Counter: 6 digits
Noise Emission:
Printing Speed Operator position Bystander position
70 rpm less than 66 dB less than 64 dB
100 rpm less than 70 dB less than 68 dB
130 rpm less than 72 dB less than 71 dB
The measurements are to be made in accordance with ISO 7779.
SPECIFICATIONS 5 September 1995
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Optional Equipment: Key Counter, Tape Dispenser
Consumables:
Name Size Remarks
Thermal master Length: 125 m (410 ft)/roll
Width: 240 mm (9.5") 260 masters can be made per roll with a Legal Drum.
304 masters can be made per roll
with an A4 Drum.
Storage Conditions:
–10 ∼40°C, 10 ∼90% RH
Ink 600 cc/pack Storage Conditions:
–5 ∼40°C, 10 ∼90% RH
Tape for tape maker 35 m (114.8 ft)/roll
5 September 1995 SPECIFICATIONS
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2. ESSENTIAL DIFFERENCES BETWEEN THE
C217 AND THE C225
No. Item Remarks
1 Paper Delivery System The paper delivery system has been changed from a
delivery roller system to a vacuum transport system. Due
to this modification, 5 mm side margins are not required
for originals.
2 Paper Table Set Switch A magnetic switch has been added to detect whether or
not the paper table is in the paper feed position. Indicator
"B" lights when the paper table is in the low position.
3 Thermal Head To minimize ink set-off, the shape of the thermal head
heating elements have been changed as shown below.
4 Paper Table Side
Fences For easy side fence positioning, a rack and pinion mechanism has been installed. The left and right side
fences move together.
5 Master Eject Box To prevent the used master from drooping when the
customer takes out the master eject box, a master holder
has been added to the master eject box.
6 Paper Delivery Table The delivery end fence and the side fences can be folded
for storing in the delivery table.
7 Master Eject Box
Capacity The pressure for compacting the master in the master eject box has been increased. The master eject box
capacity has been increased from 15 to 25 masters.
8 Economy Mode If Economy mode is selected, the thermal head energy is
reduced by 15% (this is done by changing the pulse
width). The image density will be slightly lighter, and ink
consumption will be less than normal.
C225V500.img
ESSENTIAL DIFFERENCES BETWEEN THE C217 AND THE C225 5 September 1995
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No. Item Remarks
9 Exposure Glass Bracket To prevent the scanned original from being pushed out by
the next original, the shape of the exposure glass bracket
has been changed as shown below.
10 Original Feed Spring
Plate To ensure proper feeding of thin paper, the angle of the original feed spring plate has been changed.
11 Paper Feed Timing To reduce noise which occurs when the paper hits the
2nd feed roller, the first paper feed length has been
reduced. (The buckle between the 1st and 2nd paper
feed rollers has been shortened.)
12 Skip Feed A user can select from 2 to 9 rotations of the drum while
one sheet of paper is fed.
13 A4 Size Drum (Only A4
machines) To minimize master consumption, the screen mesh length and the master cut length of the Europe/Asia machines
has been shortened. (The master consumption of the
LT/LG machines is the same as for the C217.)
14 Quality Start The first print tends to be light. To increase the image
density of the first print, Quality Start mode can be
selected. In this mode, the first print is made at 30 rpm.
15 Image Processing in
the "Darker 2" setting In the C217 model, only the A/D conversion parameters are changed when the image density setting is changed.
This does not change the density of solid black areas.
In the C225 model, if "Darker 2" is selected on the
operation panel, the thermal head energy is increased to
115% of the normal setting. The solid black areas will
become darker.
H225V501.wmf
5 September 1995 ESSENTIAL DIFFERENCES BETWEEN THE C217 AND THE C225
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3. PRINTING PROCESS
1. Master Ejecting: The machine ejects the used master
wrapped around the drum into the master
eject box.
2. Scanning: The machine scans the original using the
CCD, through the mirror and the lens,
while feeding the original.
3. Master Feeding: The machine converts the signal from the
CCD into digital signals and sends them to
the thermal head to make holes in the
master. The master then wraps around
the drum.
4. Paper Feeding: The machine sends paper separately to
the drum.
5. Printing: The machine presses the paper fed from
the paper feed section against the drum.
This transfers the ink to the paper through
the drum screen and the master.
6. Paper Delivering: The machine peels off the printed paper
with the exit pawls and air knife, and
ejects the paper onto the paper delivery
table.
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C225V502.img
PRINTING PROCESS 5 September 1995
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4. MECHANICAL COMPONENT LAYOUT
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C225V502-2.img
1. Mirror
2. Original Feed Roller
3. Original Pressure Plate
4. Exposure Lamp
5. Exposure Glass
6. Original Pick-up Roller
7. Original Friction Pad
8. Master Tension Roller
9. Platen Roller
10. Thermal Head
11. Master Roll
12. Platter Unit
13. Ink Pump
14. Paper Table
15. Paper Feed Roller
16. Friction Pad
17. 2nd Feed Roller
18. Doctor Roller
19. Press Roller
20. Ink Roller
21. Exit Pawl
22. Transport Unit
23. Paper Delivery Table
24. Drum
25. Master Eject Box
26. Master Eject Roller
27. CCD Unit
28. Original Exit Tray
29. Master Eject Unit
5 September 1995 MECHANICAL COMPONENT LAYOUT
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