Second Scanner Shift - Ricoh FT7770 Service Manual

30
April, '89

Second Scanner Shift

2.
To keep the image focused on the drum, the second scanner (second and
third mirrors) also has to move when the reproduction ratio is changed.
When the lens motor turns on, the mirror shift cam starts turning. A bear-
ing on the mirror shift bracket rides on this cam.
and down on the cam's rim, the mirror shift bracket transmits its movement
to the front mirror shift pulley through the mirror shift wire. The two scan-
ner drive wires are fixed to the mirror shift pulley by clamps. So, when the
pulley turns, it shifts the second mirror pulley slightly as shown by the ar-
rows in the above figure.
Two cam plates allow slight adjustment of the amount of motion of the
second scanner. When the angle of the cam plates is adjusted
justing screws), the cam follower tracks their inclinations and the scanner
slightly changes its position.
2-22
As the bearing rides up
(using two ad-