Paper Advance Mechanisms - Epson FX-870 Service Manual

Principles of Operation

Paper Advance Mechanisms

This section describes how the friction advance and tractor advance mechanisms work to advance
the paper through the printer.
Friction Advance Method
The paper is held between the platen and paper guide rollers and between the paper tension roller
and paper tension unit cover. The paper feed (PF) motor pinion gear, turning in the direction of
the black arrow, drives the paper advance reduction gear. The paper advance reduction gear turns
the platen gear and the paper tension roller gear. The paper advances in the direction of the white
arrow. Figure 6-4 illustrates the friction advance method when the paper is fed through the top
paper entrance.
In the friction advance method, the paper guide roller spring holds the paper against the platen.
You can release this pressure and free the paper by setting the release lever to the tractor feed
position.
Paper (Cut Sheet)
Figure 6-4. Friction Advance Operation Using the Top Paper Entrance
6-6
Paper Advance Reduction Gear
/Tractor Reduction Gear
PF Motor Pinion Gear
Epson FX-870/I 170
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