Epson Stylus pro 7700m, Service Manual

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The platen gap adjust lever, which is attached to the carriage unit, needs to be set to the appropriate position
for the paper thickness. To change the platen gap, put the printer in the PAUSE state, then press the Font
button while holding down the Alt button. The carriage unit moves the platen gap adjustment position
automatically. The platen gap adjustment mechanism consists of platen gap lever, carriage slider, and eject
frame. When you set the lever for vertical or horizontal position, the carriage slider either pushes against the
eject frame or does not push it. Then the platen gap is changed because of the up and down motion of
carriage.
Table 2-3. Platen Gap Adjust Lever Position
Paper Type Lever Position
Cut sheets Horizontal (A) (
±
0 mm)
Envelopes Vertical (B) (+0.6 mm)
2.2.4 Paper Feed Mechanism
This printer’s paper feed mechanism can feed paper only from the built-in ASF (auto sheet feeder). The paper
feed drive motor is a 4-phase, 96-pole, hybrid-type stepping motor that directly drives the paper feed
mechanism (paper advancing operation, paper pickup operation).
This motor also drives the pump
mechanism, but only when the printer is in the cleaning state. The paper feed motor uses 2-2 phase excitation,
except for the paper feed drive sequence (which is 2W1-2 phase).
Table 2-4. Paper Feed Drive Motor Specification
Item Description
Motor Type 4-phase, 96-pole, hybrid-type
Drive Voltage +35 VDC
±
5%
Coil Resistance 11.5
Ω ±
1.1
Ω
Drive Frequency 300 ~ 1800 PPS
Excitation Mode Paper feed / pump drive: 2-2 phase, 2W1-2 phase
CR Motor
CR HP Sensor
Belt Pulley
Carriage Guide Shaft
Carriage Unit
Figure 2-5. Platen Gap Lever Operation
Stylus Pro Service Manual Operating Principles
Rev.A 2-5