Siemens SINUMERIK 840D Manual page 47

Key functions for 5-axis machining
Effect of the tool length on the machine movement
Different tool length
Effect of tool orientation changes
Change in
tool orientation
In order for all these requirements to be taken into consideration, a form of 5-axis transformation
is needed that will transform the non-specific programs (in terms of kinematics) for the control
and will take into account both the tool offsets and orientation. This is achieved by means of the
SINUMERIK's TRAORI function.
© Siemens AG All rights reserved. SINUMERIK, Manual, 5-axis machining
1
2
As you can see from the example, a longer
tool will result in larger compensating move-
ments for the kinematics.
If the program has been created using a CAM
system, it will need to be recalculated when-
ever there is a change in the tool length.
Consequently, the control system needs to
know that a calculated NC program is compat-
ible with any tool length. This active tool length
compensation is integrated into the SINU-
MERIK system and does not need to be given
any consideration during programming.
If the tool orientation is changed simulta-
neously during the traversing motion (e.g. the
setting angle), the tool tip will be defined by a
complex curve motion rather than a linear one
( ).
1
However, in order to still be able to mill in a
straight line, the tool holder must compensate
this curve so that the tool tip performs the
desired motion ( ).
2
In the example with the yellow traversing
motions ( ), TRAORI compensation is
2
active.
3.5
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