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4.2
Payload
The full positioner XYZ stack will operate with loads ranging from 0-100 grams without the addition of
the preload spring to the Z-axis. The mass of the flex link is already accounted for, and the load listed in
the table below is in addition to the flex link.
The preload spring is only added to the Z-axis since it must also overcome gravity; heavy loads of 100 g
or more require an assist from this spring-loaded plunger. The X-axis and Y-axis will remain operational
with all these loads and do not require any modification to translate loads up to 400 g. Please note,
heavy loads may reduce the max velocity of the positioner stack, especially at base temperature.
With the addition of the preload spring, we cannot guarantee that stack motion will still comply with
published specifications.
For optimal performance with the spring installed, the sample center of mass should be designed to be
as close to the center axis of the positioner stack as possible.
Load (g)
Spring Plunger
0-100
Do Not Install Spring Plunger
100-250
Low Force Spring Plunger
250-400
High Force Spring Plunger
Important:
Only use the preload spring when mass is on the positioner stack (following the table
above). If a spring is used with less mass than specified above, the positioner will not be able to
counteract the expansion force lose travel moving down (-Z).
The spring is easily installed & removed from the Z-axis by hand
–
simply translate the Z-axis to the end
of its positive travel, grab the spring plunger at its base, position the smaller end on the top plate of the
positioner and push up to compress spring. Then insert into or remove from the bore holes in the stage
Figure 6: Rook with "Spring Plunger" installed.
