Oki PACEMARK 4410, Руководство по обслуживанию

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40496501TH Draft Version
36
2.2.2 Spacing operation (See Figure.2-15)
Spacing is effected by driving the carriage assembly installed to the main shaft and slide beam set
in parallel with the platen by the DC servo motor.
(a) DC motor with motor
(b) Carriage frame
(c) Carriage shaft
(d) Space belt
(e) Sensor
(f) Encoder disk
(1) Spacing operation
The carriage mounting the printhead moves in parallel with the platen along the main shaft
and slide beam. The carriage is fixed to the mini pitch belt under the carriage frame.
When the DC servo motor runs clockwise as viewed from its front side, the driving force is
transmitted to the mini pitch belt and the carriage moves from the left to the right. The DC servo
motor rotating angle and speed are controlled by the count of øA and øB signsls (with a phase
difference of about 90
°
) from the encoder and the time intervals of the signals. The rotating
direction is determined by the sign (positive or negative) of the phase difference between øA
and øB.
The mechanism is designed so that the carriage moves 2.22 inches (56.44 mm) when the DC
servo motor makes one revolution.
Encoder sensor
Encoder disk
Print head Cariage shaft
Space belt
Carriage flame
Idle pulley
DC motor
Figure 2.22