Siemens Sinumerik 840D sl Programming Manual page 282

Tool radius compensation
11.5 Collision detection (CDON, CDOF, CDOF2)
Syntax
CDON
CDOF
CDOF2
Meaning
CDON:
CDOF:
CDOF2:
Note
The number of NC blocks that are included in the collision detection, can be set via machine
data.
Example
Milling on the center point path with standard tool
The NC program describes the center point path of a standard tool. The contour for a tool that
is actually used results in undersize, which is shown unrealistically large to demonstrate the
geometric relationships in the following figure. The control also only has an overview of three
blocks in the example.
Figure 11-6
282
Command for the activation of the collision detection.
Command for the deactivation of the collision detection.
With deactivated collision detection, a search is made in the previous traversing block (at
inside corners) for a common intersection for the current block; if necessary the search
is extended to even earlier blocks.
Note:
CDOF can be used to avoid the faulty detection of bottlenecks, resulting, for example, from
missing information that is not available in the NC program.
Command for the deactivation of the collision detection during 3D circumferential milling.
The tool offset direction is determined from adjacent block parts with CDOF2. CDOF2 is
only effective for 3D circumferential milling and has the same meaning as CDOF for all
other types of machining (e.g. 3D face milling).
Compensation motion for missing intersection
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Fundamentals