Adixen ASM 142, User Manual

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A 300
Analyzer cell operating principle
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Design and
manufacture
Great care has been taken with the design and manufacture of
the cell in order to repeatedly obtain the same characteristics
and to achieve excellent stability:
– the metal parts are made of stainless steel,
– the filament holder is made of machined aluminium,
– there is an integral amplifier.
The cell assembly is composed of:
– a vacuum chamber or deflection chamber,
– an optic holder flange,
– a permanent magnet,
– an amplifier.
• The vacuum chamber:
The analysis cell vacuum chamber is made of light alloy. It is
hollow with a rectangular opening into which the electrodes,
(that are installed on the «optics holder» flange) are placed.
• The optics holder flange:
The optics holder flange supports all the electrodes and electrical
connections in the cell. They include:
– the sealed power supply socket, mounted on a metal gasket,
– the amplifier, mounted on an elastomer gasket,
vthe supporting block which screens the target and on which the
source of ions is mounted,
– the source of ions, which is made up of 2 parts:
• a filament holder,
• an ionization chamber with a stainless steel electron collector
and a mass ion emitter.
The filament holder mechanically positions the tungsten filament
with respect to the ionization chamber.
The electron collector and the filament have been designed
and positioned so that the temperature of the electron collector
stabilizes at 400°C under bombardment and radiation from the
filament. The cell is thus rendered immune to contamination from
the pieces being tested without the need of any special heating
system.
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