Vacuum System - AGFA Avantra 36/44 Service Manual

Section I: Imagesetter
2.13.4.3 Flappers
Because the shrouds are not as wide as the drum, the system requires two flappers
to hold the media against the drum. The flappers assist the media through the take-
up side during the loading process.
During the loading sequence, the media stops feeding at a point a few inches short
of the take-up punch. The two flappers come down and hold the media against the
drum. This is called the flappers' load position. Once the flappers are in place, the
loading sequence moves the media through the take-up side.
After the loading sequence is complete, the flappers go up, which is called their
image position. A stepper motor and two sensors control each flapper. The sensors
tell the system when the flappers are in their load (down) or image (up) positions.

2.13.5 Vacuum System

The Avantra 36/44 has a multi-port vacuum system. The system contains a 115 volt
vacuum pump, transformer, vacuum board, vacuum valves and voltage sensor
relay. The following describes each component.
2.13.5.1 Vacuum Pump
The pump removes the air between the drum and the media. The vacuum remains
off only during media movements. Refer to Figure 2-11.
3
2
1
Figure 2-11 The vacuum pump.
–Vacuum pump. –Valves. –Electronics box.
Functional Analysis 2-23