2.2.2 SCANNER DRIVE
[C]
[F]
[D]
[E]
[B]
[A]
[G]
The scanner motor is a dc servo motor. The 1st and 2nd scanners [A, B] are driven by the scanner motor [C] through the timing belt [D], scanner drive pulley [E], scanner drive shaft [F], and two scanner wires [G].
The MCU (Motor Control Unit) board controls the scanner motor. The exposure lamp scans a sheet with 100% magnification at 515 mm/s and returns to the scan position for the next scan at 2500 mm/s.
Magnification and Reduction
Magnification and reduction in the main scan direction are done in the IPU board.
Magnification and reduction in the sub scan direction, however, are done by controlling the speed of the scanner motor in sync with the main scan processing done in the IPU.
•Magnification above 101% is done in the IPU. For example, at 200% magnification, the IPU doubles magnification while the scanner motor speed remains at 100%.
•Reduction in the range 51% to 100% is done by the scanner motor.
•Reduction in the range 25% to 50% is done by the scanner motor, assisted by IPU processing. For example, at 40% reduction, the scanner motor speed is 80% and the IPU reduces the image by 1/2.
•Reduction below 25% is done by the scanner motor, assisted by IPU processing. For example, at 24% reduction the scanner motor speed is 96% and the IPU
reduces the image by 1/4.
NOTE: Magnification in the sub scan direction can be adjusted by changing the scanner motor speed with SP4008 (Scanner Sub Scan Magnification).
PTM | B070/B071 |
