Star Micronics LC-8521, Technical Manual

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4-2. Print Head Carrying Mechanism
The print head carrying mechanism consists of a carriage, timing belt, carriage motor, and home position detector.
Carriage
The carriage is supported horizontally by the carriage stay and rear angle. The carriage moves from side to side with
the print head mounted above it. A timing belt is clamped to the base of the carriage and a shield plate is mounted
at the base for home position detection.
Timing Belt
The timing belt is suspended between the timing pulley of the carriage motor and the timing pulley of the tension
lever. The timing belt maintains a constant tension.
The timing belt is also clamped to the base of the carriage so that it can move the carriage accurately with driving
force from the carriage motor.
Carriage Motor
The carriage motor is a HB (Hybrid) 4-phase, 200-pole pulse motor driven by pulse signals from the control circuit.
The rotational rate depends on the number of pulses per unit time. By varying this rotational rate (carriage carrying
rate), the size of the horizontal letters can be changed in each print mode.
Home Position Detector
Carriage
Rear Angle
Carriage Motor
Carriage Stay
Print Head
Timing Belt
Fig. 2-6 Print Head Carrying Mechanism