Epson Stylus CX7300 Service Manual page 48

EPSON Stylus CX7300/CX7400/DX7400/NX200/TX200 series/SX200 series/Stylus CX8300/CX8400/DX8400/NX400/TX400 series/SX400 series Revision C
2.1.5.1 Paper Loading Mechanism (ASF Unit)
The paper loading mechanism loads paper from the ASF unit and feeds paper to the PF
roller. The ASF unit includes the hopper, change lever, LD roller shaft, and clutch
mechanism.
The change lever and the clutch mechanism play an important role in the paper loading
operation as described below.
1. ASF home position detection function
The change lever and the clutch mechanism are used to detect the ASF home
position.
The counterclockwise rotation of the PF motor brings the change lever to engage
with the clutch mechanism. The ASF home position is detected by the engagement
of the change lever at the beginning of the paper loading operation. At this time,
paper is not fed to the PF roller because the PF motor drive force is not yet
transmitted to the LD roller shaft.
2. Paper loading function
When the change lever is disengaged from the clutch mechanism by the
counterclockwise rotation of the PF motor pinion gear, the printer changes to the
paper loading state from the ASF home position detection state. The PF motor
drive force is transmitted to the LD roller, and paper is fed from the ASF unit.
The rotation of the two cams on the LD roller feeds paper into the printer.
Larger cam: moves the hopper
Smaller cam: moves the paper back lever
When the first sheet of paper has been fed, the second sheet is returned to the standby
position by the hopper and the paper back lever, which are moved by the cams.
The following sections explain the paper loading sequence and operations of each
components.
OPERATING PRINCIPLES
S 1: ASF H P
TEP OME OSITION
The counterclockwise rotation of the PF motor pinion gear (as seen from the left of the
printer) causes the change lever to push down on the clutch lever, and the clutch lock
tab is disengaged from the clutch gear as shown in
drive transmission to the LD roller shaft, and the shaft does not move at all. At the
same time, the hopper is pushed down by the two cams on the LD roller shaft, and the
paper back lever is set at the position to prevent paper from being fed. The "ASF home
position" indicates all of the above statuses.
Paper Back Lever Cam
Hopper Release Cam
Base Frame
Combination Gear E Combination Gear D
(LD Roller/Clutch)
Spur Gear C
(PF Roller)
Combination
Combination
Gear A Combination
(Change Lever)
Gear B
(Pump Unit)
Figure 2-9. ASF Home Position
Overview
Figure 2-9. This cuts the PF motor
LD Roller
Extension Spring
Clutch Clutch Gear
Change Lever
Clutch Lever
Gear C
Hopper
Compression
Spring
Paper Back Lever
Clutch Lock
Tab
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