Fresa G024, Руководство по обслуживанию

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31 March, 1999 OPTICAL UNIT
2-23
Detailed
Descriptions
2.3.3 LD UNIT
LD safety switch
A safety switch is provided to prevent accidental laser emission while the front
cover is open for maintenance.
The safety switch is on the +5V DC line from the power supply unit to the LD unit
via the MCU.
When the front cover is opened, the safety switch shuts off the +5V DC line to the
LD unit.
LD unit configuration
The LD unit consists of a laser diode (LD) [A], collimating lens [B], aperture [C], and
LD control board [D]. The collimating lens focuses the laser beam into an
accurately parallel beam.
The aperture then prevents the beam from expanding beyond the required beam
diameter [E] on the OPC belt.
G N D
+ 5 V
+ 2 4 V
Power supply
unit
LD unit
M C U
+ 5 V I N T
+ 5 V
Front cover
switch
LD safety
switch
To the paper exit cover
switch
Door safety
switch
G024D518.WMF
G024D511.WMF
[A]
[B]
[C]
[D]
E