Epson Stylus Photo 925, Руководство по обслуживанию

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EPSON Stylus Photo 925 Revision A
Operating Principles Overview 33
2.1.4 Paper Feeding Mechanism
The paper feeding mechanism consists of the Paper Feed Motor (PF Motor), Paper
Feed Roller (PF Roller), Driven Roller, Paper Eject Roller and Star Wheel Roller.
2.1.4.1 Paper Feed Motor (PF Motor)
A DC motor is employed. Table 2-4 below shows the specifications for the paper feed
DC motor.
To ensure an improved paper feed accuracy, this printer uses closed loop control by the
DC motor and rotary encoder. In addition to the conventional paper eject roller, this
printer has another paper eject roller in the newly employed cutter mechanism. This
newly mounted paper eject roller is also driven by the PF Motor.
2.1.4.2 PF Motor Drive Transmission Path
V
PF motor drive transmission path
PF Motor Pinion Gear
→
Spur Gear 73.6(PF roller)
V
Paper eject roller drive transmission path
PF Motor Pinion Gear
→
Spur Gear 73.6(PF Roller)
→
Combination Gear 13.6, 33
→
Spur Gear 25.6 (Paper eject roller)
V
Paper eject roller (in the cutter mechanism) drive transmission path
PF Motor Pinion Gear
→
Spur Gear 73.6 (PF roller)
→
Combination Gear 13.6ÅA33
→
Combination Gear 47ÅA19.2
→
Spur Gear 19.2 (Paper eject roller)
Figure 2-7 below shows the transmission path of the driving force from the PF Motor
and the names of parts on the path.
Figure 2-7. Paper Feeding Mechanism
When paper is loaded from the ASF, the PF sensor detects the paper loading and the
paper feed mechanism conveys the paper once until the leading edge of the paper
arrives at the center of the Front Paper Guide. (If the paper loading is not detected,
“Paper Out” error is displayed. If paper loading is detected after paper eject operation,
“Paper Jam” error is displayed.) After that, to pull up the slack of the paper, the
mechanism move back the paper toward the ASF unit by the specified number of steps
and then conveys the paper toward the Front Paper Guide to the specified standby
position.
Once printing starts, the paper is conveyed by the driving force of the PF Roller and by
the Driven Roller and when the paper bottom end is to be printed and conveyed, the
paper is transported by the driving force of the PF Roller and by the Star Wheel Roller.
Table 2-4.PF Motor Specifications
Items Specifications
Motor type DC motor with brush
Drive voltage 42V +/-5% (voltage applied to the driver)
Armature resistance 27.1
Ω
+/-25%
Inductance 19.8mH +/-25%
Drive method PWM drive system
Driver IC A3974
Spur Gear 73.6
(PF Roller)
Spur Gear 25.6
(Paper eject
roller)
Combination
Gear 13.6, 33
PF Motor
Pinion Gear
Spur Gear 19.2
(Paper Eject
Roller in cutter
mechanism)
Combination
Gear 47, 19.2
Paper eject roller
Paper Eject Roller in cutter
mechanism