Davin J012, Service Manual

Page: 333 / 365

The main gear [1] of the vertical motor of the printer drives the duplex drive gear [2].
Here is a brief summary of how the duplex unit operates:
• The trailing edge sensor goes off after the trailing edge of the sheet passes overhead and the front
side has printed.
• The vertical motor stops, and paper transport stops.
• The vertical motor reverses.
• The printed sheet feeds into the Duplex Unit.
• Once again, the vertical motor reveres.
• The inverted sheet feeds into the printer.
• The 2nd side of the sheet prints.
Duplexer Cover Switch
The Duplex Unit cover open switch [1] is a microswitch.
This switch detects if the cover is open or closed.
When the cover is closed the switch is closed. The circuit is closed at the 4 terminal pins [2] that connect to
the DIB. The printer controls the Duplex Unit through the DIB.
The switch breaks the connection between the printer and Duplex Unit when the cover is open.
6. Detailed Section Descriptions
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