Ricoh D124-17 Service Manual page 15

• The operation of the horizontal motor is controlled by a long horizontal encoder strip (5) stretched
across the width of the main unit.
• A horizontal encoder sensor (6) mounted on the back of the carriage unit reads the codes on the
strip to control operation of the motor and carriage unit as the carriage unit moves left and right.
Vertical paper feed
• A vertical feed motor (1) and drive belt (2) rotate the registration roller (3) and exit roller (4) to
feed paper in the paper path. The diameter of the exit roller is slightly larger than the diameter of
the registration roller. This keeps the paper slightly stretched to prevent buckling.
• The operation of the vertical motor is controlled by a vertical encoder wheel (5) mounted on the left
side of the machine in front of the vertical feed motor.
• A vertical encoder sensor (6) brackets the edge of the vertical encoder wheel. It reads the codes
on the edge of the wheel as it rotates, to control vertical paper feed.
• The vertical encoder HP sensor (7) stops the motor when the wheel reaches the home position at
the end of a job.
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