Epson LQ-1170 - Page 44

REV.-A
Pull Tractor Method
Pull tractor feeding is basically the same as push tractor feeding. In push tractor feeding, the tractor
(the paper advance mechanism) is before the paper entrance. It pushes the paper through the printer
mechanism. In pull tractor feeding, however, the tractor is after the paper entrance. Because
it PUIIS
the paper through the printer mechanism, it requires no paper tension unit. Figure 2-6 illustrates pull
tractor operation when you insert paper into the bottom paper entrance.
Paper (Continuous)
/
Pull Tracter
/
“’ten ‘---.4+
Tractor Gear
Paper Tension Roller
Transmis~i~n ~~ar
Motor
Wlod
71
Paper Feed Motor
Pinion Gear
~
Paper Feed Reduction
Gear
Figure 2-6. Pull Tractor Operation
Push-Pull Tractor Method
The push-pull tractor method is a combination of the push tractor and pull tractor methods. In push-pull
tractor feeding, the printer uses two tractors, one in front of and one behind the paper entrance, to
advance the paper. They simultaneously push and pull the paper through the printer mechanism. Figure
2-7 illustrates push-pull tractor operation.
Paper
(Continuous)
/
/
,/
/’
Pull
/’
Push Tractor
Tractor
Tractor Gear
Paper Tension Roller
Transmission Gear
Tractor Reduction Gear
)
Paper Feed
Motor
Platen Gear
/
L!&) I “ I
Figure 2-7.
Paper Feed Mo’tor ~
I
Pinion Gear
Push-Pull Tractor Operation
2-5