Paper Feed Mechanism - OKIDATA ML320 Service Manual

2.4.04 Paper Feed Mechanism

The paper feed mechanism consists of the following items.
Stepper Motor (with drive gear)
Reduction Gear
Platen
Push Tractor Unit
Pressure Rollers (friction feed rollers)
Pull Tractor Unit (optional)
Paper Feed Operation
The line feed motor is mounted on the left side frame of the printer. It drives the platen via the
reduction gear. If the optional tractor unit is installed, platen rotation is transmitted through the
idle gear to the tractor unit.
The paper feed mechanism is designed so when the stepper motor rotates 48 steps (360 degrees),
paper is fed 0.17 inch (4.23 mm).
Friction Feed
When the release lever is set to the friction feed position, the release lever disengages the change
gear from the tractor gear. At the same time, the release lever applies pressure to push the pressure
rollers against the platen, allowing paper to be fed.
Service Guide ML320/ML321
Chapter 2 Principles of Operation
Page: 35