How To Manage The Media Vacuum; The Media Vacuum System - Oce Arizona 200 GT User Manual

The Media Vacuum System

How to Manage the Media Vacuum

The Media Vacuum System
Introduction
The Arizona 200/250 GT uses a low-flow, high-vacuum system to secure rigid media
for printing on the printer table. A fabricated aluminum overlay sheet placed on the
surface of the table creates the vacuum field. The overlay sheet is pin-registered to
the table. A rotary vane vacuum pump is used to evacuate the chamber of air between
the sheet and the table. Three air-feed ports connect the chamber to the vacuum
pump through a series of manually operated flow valves. These valves are used to
activate or shut down the different vacuum zones. In order for the system to work
effectively during printing all the circular pockets on the top surface of the overlay
sheet connected to an active vacuum chamber must be covered. This creates a closed
vacuum system. A bleed valve is provided to adjust the level of vacuum, if so
desired.
Vacuum Overlay Sheet
The vacuum overlay sheet is supported on the table by 0.5mm diameter formed
half-shear features. This produces a small gap between the sheet and the top of the
table for air to flow. Foam tape applied around the perimeter of the sheet provides an
edge seal. Additional foam tape can be used within the perimeter to create up to three
custom vacuum zones. The 0.5mm diameter half-shear feature creates the equivalent
of a counter-bored hole or circular pocket on the top surface of the panel. Each of
these pockets is connected to the sealed underside of the panel by 1.5mm diameter
punched holes.
Default Vacuum Zones
The printer is shipped from the factory configured with one large vacuum zone that
accomodates the maximum media size. There are two suggested custom vacuum
zone configurations, one for Metric and one for Imperial units. These zones can be
set up for common media sizes, and can be modified with additional foam tape. The
next section has more information on how to create custom zones How to Create
Custom Vacuum Zones .
86 Chapter 5 How to Operate the Arizona 200/250 GT