Ricoh B230 Service Manual

							Basic Operation 
SM 19 B789 
B789 
Document length detection 
From when the skew correction sensor switches on until it switches off, the CPU counts 
the transport motor pulses. The number of pulses determines the length of the original. 
Feed-in cycle 
When the original size for the copy modes listed below cannot be determined, the image 
cannot be correctly scaled (reduced or enlarged) or processed until the original’s length 
has been accurately detected. The length must be determined before the image is 
scanned. 
 
Auto Reduce/Enlarge 
Centering 
Erase Center/Border 
Booklet 
Image Repeat 
 
The originals follow this path: 
1. Length detection 
 Scanning glass  Inverter table 
2. Inverter table 
 Scanning glass  Inverter table (restores the original order) 
3. Inverter table 
 Scanning glass (image scanned)  Exit tray 
Normal feed-in 
In a copy mode other than those listed above, when the reduction/enlargement ratio has 
been determined, the originals are scanned normally. In order to store the scanned 
images, a large area of memory (the detected original width x 432 mm length) is prepared. 
Next, only the portion of the image up to the detected original length is read from memory 
and printed.  
						

							Basic Operation 
B789 20  SM 
2.2.3 PICK-UP AND SEPARATION 
 
The original is set with the image facing up. The original pushes actuator and the original 
set sensor is activated. 
After pressing the start button, the feed clutch is activated and the original feed unit [A] 
moves down. At the same time, the pick-up solenoid is activated and the original table lifts 
until the original comes in contact with the pick-up roller [B]. The pick-up roller then feeds 
the top sheet of paper.  
After being fed from feed belt [C], the topmost sheet is separated from the stack by the 
separation roller [D] and sent to the skew correction roller. 
The mechanism is an FRR system, consisting of the original feed belt [C] and separation 
roller [D].   
						

							Basic Operation 
SM 21 B789 
B789 
2.2.4 SKEW CORRECTION 
 
When an original is fed into the feeder, the feed motor [B] rotates forwards. At this time, 
the feed belt turns but the skew correction roller [C] does not. Because of this, when the 
leading edge of the paper gets to the skew correction roller, skew in the original is 
removed. 
A short time after the leading edge of the original turns on the skew correction sensor [A], 
the feed motor [B] turns off for 40 ms and rotates in reverse. At this time, the skew 
correction roller [C] and the feed belt both turn, and original feed continues. 
The original is fed by the skew correction roller after the feed clutch [D] has turned off.  
						

							Basic Operation 
B789 22  SM 
2.2.5  ORIGINAL TRANSPORT AND EXIT 
Single-Sided Originals 
 
The feed motor feeds the separated original to the skew correction roller [A] at maximum 
speed. After skew correction, the feed and transport motors feed the original through the 
scanning area at a lower speed (the scanning area contains the original exposure guide 
[B] and DF exposure glass [C]). After scanning, the original is fed out by the transport 
roller [D] and exit roller [E]. 
Double-Sided Originals 
 
After skew correction, the feed and transport motors drive the skew correction roller [A], 
registration roller [B], transport roller [C] and the exit roller [D]. The front side of the original 
is then scanned. 
When the original exit sensor detects the leading edge of the original, the junction gate 
solenoid is activated and the junction gate [E] opens. The original is then transported  
						

							Basic Operation 
SM 23 B789 
B789 
towards the inverter table.  
Soon after the trailing edge of the original passes the exit sensor, the junction gate 
solenoid switches off and the junction gate [E] is closed. When the original has been fed 
onto the inverter table, the feed motor switches on in reverse. The original is then fed by 
the inverter roller [F], and then by the skew correction roller [A] and registration roller [B] to 
the scanning area (where the reverse side will be scanned). 
 
The original is then sent to the inverter table again to be turned over. This is done so that 
the duplex copies will be properly stacked front side down in the exit tray [G] in the correct 
order. 
Original Sensor 
During one-to-one copying, copy paper is fed to the skew correction roller in advance 
(while the original is still being scanned), to increase the copy speed. The original sensor 
monitors the stack of originals in the feeder, and detects when the trailing edge of the last 
page has been fed in. The main CPU then stops the copier from feeding an unwanted 
extra sheet of copy paper. 
2.2.6  CONDITIONS FOR JAM DETECTION 
Jam Mode Detection Timing 
When turning on the machine, the skew correction sensor, registration 
sensor or exit sensor detects an original. 
When the cover is closed or DF is down, the skew correction sensor, 
registration sensor or exit sensor detects an original. Initial 
When the cover is opened or DF is lifted up, the skew correction 
sensor, registration sensor or exit sensor detects an original.  
						

							Basic Operation 
B789 24  SM 
The skew correction sensor does not turn off even if the original was 
fed by the maximum length of the original + 150 mm after the skew 
correction sensor turned on. 
The registration sensor does not turn off even if the original was fed by 
its length x 1.5 after the registration sensor turned on. Sensor stays 
on too long 
The exit sensor does not turn off even if the original was fed by its 
length x 1.5 after the exit sensor turned on. 
The skew correction sensor does not turn on even if the original was 
fed by transport path length x 1.5. 
The registration sensor does not turn on even if the original was fed by 
transport path length x 1.5 after the skew correction sensor turned on. Sensor does 
not come on 
The exit sensor does not turn on even the original was fed by transport 
path length x 1.5 after the skew correction sensor turned on. 
  
						

							Dip Switches 
SM 25 B789 
B789 3. SERVICE TABLES 
3.1 DIP SWITCHES 
 
DIP-SW 
1 2 3 4 Function 
0  0  0  0  Normal operating mode (Default) 
0  0  0  1  Free run: With original: One-sided mode: 100% speed 
0  0  1  0  Free run: With original: Two-sided mode: 100% speed 
0  0  1  1  Free run: No original: One-sided mode: 100% speed 
0  1  0  0  Free run: No original: Two-sided mode: 100% speed 
0  1  0  1  Free run: With original: One-sided mode: 32% speed 
0  1  1  0  Free run: With original: Two-sided mode: 32% speed 
0  1  1  1  Free run: With original: One-sided mode: 70% speed 
1  0  0  0  Free run: With original: Two-sided mode: 70% speed 
1  0  0  1  Free run: With original: One-sided mode: 200% speed 
1  0  1  0  Free run: With original: Two-sided mode: 200% speed 
1  0  1  1  Transport Motor On 
1  1  0  0  Feed Motor On 
1  1  0  1  Transport Motor On with random mode 
1  1  1  0  Feed Motor On with random mode 
1 1  1  1  
  
						

							 
 
 
 
1 BIN TRAY 
B790