Siemens SINUMERIK 840D sl Function Manual page 1930

Detailed Description
2.8 Special handling of tool compensations
Toolholder with orientation capability
If a toolholder with orientation capability is active, the temperature compensation vector is
rotated simultaneously to any change in orientation. This applies independently of any active
orientation transformation.
If a toolholder with orientation capability is active in conjunction with a generic 5axis
transformation or a transformation with rotating linear axis, the temperature compensation
vector is subjected to both rotations.
Note
While transformations with rotating linear axes take changes in the tool vector (length) into
account, they ignore its change in orientation, which can be effected by a toolholder with
orientation capability.
Temperature compensation values immediately follow any applied change in orientation.
This applies in particular when an orientation transformation is activated or deactivated.
The same is true when the assignment between geometry axes and channel axes is
changed. The temperature compensation value for an axis is reduced to zero
(interpolatively), for example, when it ceases to be a geometry axis after a transformation
change. Conversely, any temperature compensation value for an axis, which changes over
to geometry axis status, is applied immediately.
Examples
Temperature compensation in tool direction
Example of a 5axis machine with rotating tool, on which the tool can be rotated about the C
and B axes.
In its initial state, the tool is parallel to the Z axis. If the B axis is rotated through 90 degrees,
the tool points in the X direction.
Therefore, a temperature compensation value in the following setting data is also effective in
the direction of the machine X axis if transformation is active:
SD42960 $SC_TOOL_TEMP_COMP[2] (Temperature compensation with reference to tools)
If the transformation is deactivated with the tool in this direction, the tool orientation is, by
definition, parallel again to the Z axis and thus different to its actual orientation. The
temperature offset in the X axis direction is therefore reduced to zero and reapplied
simultaneously in the Z direction.
Example of a 5axis machine with rotating tool (transformation type 24). The relevant
machine data are listed below:
• The first rotary axis rotates about Z.C-axis
• The second rotary axis rotates about Y B-axis
142
Basic logic functions: Tool Offset (W1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0