Oki ML520 - Manual (Page 84)

Page: 61
Service Guide ML520/521
Chapter 2 Principles of Operation
2.2.06 Paper Detection Mechanism
Top Feed Paper Detection
When cut sheet paper is inserted into the printer, Point A of the Rear/Top Paper Feed Lever is pushed
backward, causing the Sensor Lever to rotate.
As the Sensor Lever rotates, it contacts the Rear Sensor Lever. This makes the Rear Sensor Lever rotate.
The Rear Sensor Lever rotates, unblocking the Rear / Top Paper End Sensor (SNS1).
Rear Feed Detection
When paper is fed from the Rear Push Tractor, Point B is pushed backward. This makes the Sensor
Lever rotate.
As the Sensor Lever rotates, it contacts the Rear Sensor Lever. This makes the Rear Sensor Lever rotate.
The Rear Sensor Lever rotates, unblocking the Rear / Top Paper End Sensor (SNS1).
Bottom Feed Detection
When the paper is fed from the bottom of the printer, Point C is pushed, rotating the Bottom Paper End
Lever.
As the Bottom Paper End Lever rotates, it contacts the Bottom Sensor Lever. This makes the Bottom
Sensor Lever rotate.
The Bottom Sensor Lever rotates, unblocking the Bottom Paper End Sensor (SNS2).
NOTE:
The method for detecting a paper-end condition is the reverse of the above.
PAPER-END is detected when the Bottom Paper End Sensor (SNS2) is blocked.