Zeiss Focal CC, Инструкция по эксплуатации

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ZEISS 3 Product and Functional Description of Focal CC | 3.3 Internal Gaseous Nitrogen Interconnection
Function
A flexible silicone hose
2
guides gaseous nitrogen from a bayonet gaseous interconnect to a
carbon nozzle
9
, which is mounted on a sprung loaded swing arm
5
. A pusher
6
mounted on the knife arm pushes the swing arm away from the specimen when the knife is
brought close to the specimen. The nozzle stays in either of two positions according to the ultra-
microtome software control of the knife position:
§
Cutting position
§ Imaging position
As long as the Focal CC is activated in SmartSEM, the gas flow through the hose is always on, re-
gardless which position the nozzle is in. The ultramicrotome software is not aware of the status of
the Focal CC.
Cutting Position
As the ultramicrotome moves to the cutting position, the pusher
6
pushes the swing arm
5
away from the specimen. The exact position of the nozzle in the cutting position is not criti-
cal, it is simply pushed out of the way.
Imaging Position
In the imaging position, the nozzle
9
must be very close to a block-face specimen
8
in or-
der to gain the maximum benefit of the localized gas flow. In the vacuum of the specimen cham-
ber, the gas molecules disperse very quickly as soon as they exit the nozzle tip and so proximity
has a large impact on performance.
3
2
1
Fig. 4: Nozzle in the imaging position with the knife arm cleared away from the specimen
1 Specimen 2 Nozzle
3 Screw clamp for nozzle holding and ad-
justment
In this example the Focal CC is in the imaging position. The nozzle
2
is close to the specimen
1
and the knife is cleared from the specimen.
3.3 Internal Gaseous Nitrogen Interconnection
Purpose The Teflon hose transports gaseous nitrogen from the chamber port feedthrough to a bayonet
connector. A flexible silicone hose transports gaseous nitrogen from the bayonet to the swing-
arm assembly on the ultramicrotome. Both, the Teflon hose and the silicone hose are push-on fit-
tings.
Position There are different bayonet configurations:
§
The bayonet is attached to the specimen chamber roof. The hose connection routes around
the pole piece on the roof of the specimen chamber, away from all detectors.
§
The bayonet is attached to the specimen chamber wall or to the replacement door near
where the ultramicrotome is mounted. These configurations allow for simpler routing of the
silicone hose between the bayonet and the ultramicrotome.
Instruction Manual ZEISS Focal CC | en-US | Rev. 2 | 349561-8021-000 13