Tally T2265 SprintPro, Maintenance Manual

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3.2
Mechanical Functions
3.2.1
Head/Platen
Clearance
The worm gear (see principle drawing) determine the basic head distance. You can
imagine the worm gear as a mechanical memory. During initialisation (power up) of
the printer the head distance stepper moves the toothed segment on block at the
worm gear. Now the printer has its basic point and can count the steps forward which
are stored in the firmware. The stepper tolerance is within one bit pattern (equals 4
steps).
Principle
B
Mean point
carriage axle
Bearing point
eccenter
WORM GEAR
"MEMORY"
Motor
pinion
13 teeth
Stepper
Toothed wheel
84/14
Thoothed segment
26°
B
A
Lever
Adjust Area:
Tolerance Tolerance
A
min. 0 max.
Head Distance
26°
B
A
Functional Description Mechanical Functions
3-3