Epson LG1-1070 Service Manual page 181

Pull Tractor Method
Using pull tractor feed to advance the paper is basically the same as using push tractor feed. In push
tractor feed, the TRACTOR ASSY. (paper advance mechanism) is before the paper entrance. It pushes
the paper through the PRINTER MECHANISM. Pull tractor feed, however, has the opposite arrangement,
with the tractor situated after the paper entrance. Since it pulls the paper through the PRINTER
MECHANISM, it requires no paper tension unit. Figure 2-6 illustrates pull tractor operation tractor when
paper is inserted through the bottom path.
Push-Pull Tractor Method
This is a combination of the push tractor and pull tractor methods. Two tractors are used, one in front
of and one behind the paper entrance, to advance the paper. They act simultaneously to push and pull
the paper through the PRINTER MECHANISM. Figure 2-7 illustrates push-pull tractor operation.
TRACTOR AS
Paper (Continuous)
COMBINATION GEAR, 8.5, 30
Figure 2-6. Pull Tractor Operation
Paper (Continuous)
SPUR GEAR, 16
COMBINATION GEAR, 8.5, 30
Figure 2-7. Push-Pull Tractor Operation
2-5
SPUR GEAR,
16
per Feed Motor Pinon Gear
SPUR GEAR, 40
MOTOR, PF
REV.-B
Motor
I