Scanner Drive - Ricoh B202 Service Manual

SCANNING

6.3.2 SCANNER DRIVE

[E]
[A]
[B]
[C]
[D]
B178D514.WMF
The scanner motor [B] drives the 1st scanner [A] and the 2nd scanner [E] through
the scanner drive pulley, scanner drive shaft [C], and two scanner wires [D].
Book mode -
The SBU board controls the scanner drive motor. The 2nd scanner speed is half
that of the 1st scanner.
In reduction or enlargement mode, the scanning speed depends on the
magnification ratio. The returning speed is always the same, whether in full size or
magnification mode. The image length change in the sub scan direction is done by
changing the scanner motor speed. In the main scan direction it is done by image
processing on the IPU board.
You can adjust the magnification in the sub-scan direction by changing the scanner
motor speed with SP4-008.
ARDF mode -
The scanners always stay in their home position (the scanner HP sensor detects
the 1st scanner) to scan the original. The ARDF motor feeds the original through
the ARDF. In reduction/enlargement mode, the image length change in the sub-
scan direction is done by changing the ARDF motor speed. Magnification in the
main scan direction is done in the IPU board. This is the same as for book mode.
You can adjust magnification in the sub-scan direction by changing the ARDF
motor speed with SP6-017.
SM 6-21 B202/B178/B180