Laser Beam Pitch Change Mechanism - Ricoh SP5 Series Service Manual

June 30, 1998

2.4.5 LASER BEAM PITCH CHANGE MECHANISM

P1
P2
P1: 400 dpi
P2: 600 dpi
A printer option is available for this machine and the resolution of the printer is 600
dpi. The machine changes the resolution between 400 and 600 dpi by rotating the
LD unit.
When the LD positioning motor [A] turns, the metal block [B] (which contacts the
LD unit housing [C]) moves up and down. This changes the position of the L2 laser
beam (L1 does not move).
Both LD unit positions are at fixed distances from the LD home position sensor [D]
(measured by motor pulses). Usually, the LD unit moves directly to the proper
position. However, when the number of times that the resolution has changed
reaches the value of SP2-109-5, the LD unit moves to the home position (the home
position sensor activates), then it moves to the proper position. This recalibrates
the LD unit positioning mechanism.
2 mm
A229D525.WMF
2-47
LASER EXPOSURE
[B] [D]
[C]
[A]
A229D516.WMF