Siemens SINUMERIK 840D sl Function Manual page 464

TE1: Clearance control
11.2 Clearance control
Note
In all the figures in this chapter, the traversing movement of the machining head needed in
order to machine the workpiece is in the direction of the Y coordinate, i.e. perpendicular to
the drawing plane.
As long as the tool orientation, and hence the compensation vector, is perpendicular to the
workpiece surface, no disadvantage for the machining process results from the compensation
movements of the clearance control.
If a tool setting angle is needed for technological reasons, with the result that the tool
orientation is no longer perpendicular to the workpiece surface, the machining point on the
workpiece surface is shifted during compensation movements of the clearance control along
the standard compensation vector.
Figure 11-7
The reason for the shift in the machining point is the X component (K
vector parallel to the workpiece surface. The TCP of the tool, and thus the machining point B,
is shifted by this amount.
Programmable compensation vector
When using the programmable compensation vector, the compensation movements of the
clearance control are in the direction of the programmed vector, and not in the direction of the
tool orientation.
The X component specified above (K
vector is defined perpendicular to the workpiece surface. This does not cause the machining
point (B) to be shifted as a result of the compensation movement of the clearance control.
464
Standard compensation vector
) is omitted because the programmable compensation
X
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
) of the compensation
X
Special Functions