Tally T2040, Руководство по обслуживанию

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3.2
Mechanical functions
FAW
3.2.1
Function
The motor FAW controls the pushbar which is used to select the functions. After
switch-on, the carriage moves to the left-hand side of the printer and presses
against the seesaw lever, thus pushing the seesaw outwards. This causes the see-
saw to tilt, and the FAW motor proceeds to control paper tray selection.
The pushbar can execute 6 steps, each 5.5 mm apart. It engages with either the
gear shaft front, the gear shaft rear or the friction front and rear. The gear shafts
control the position of the gears which are used to drive tractors 1, 2 and 3, sheet
feeder rear (SFR) and sheet feeder front (SFF) respectively.
3.2.2
Pushbar position check
The home position sensor checks the position of the pushbar and, therefore, the se-
lected paper source. There is a position ruler located on the pushbar. After switch-
on, the photoelectric barrier in the home position sensor scans this ruler; it moves to
the next ridge edge and measures the width of the ridge. The position of the push-
bar is fed back to the firmware in this way.
Ridge 1 (narrow) Tractor 2
Ridge 2 Tractor 3
Ridge 3 Tractor 1
Ridge 4 (wide) Friction switched on (friction front
and rear)
3.2.3
Pushbar positions
Possible pushbar positions:
The numbers in brackets in the following description of the pushbar positions are
items which can be found in chapter 6
Spare parts and schematics .
6 1 2 3 4 5
Trac2 Trac3 Trac1 Friction
SFF
Friction
SFR +
Single
1
2
3
4
Ridge
Mechanical functions FAW Functional description
3-2