Siemens SINUMERIK 840DE Programming Manual page 344

Tool offsets
8.11 Smooth approach and retraction
Motion steps between start point and end point (G340 and G341)
The approach characteristic from P
In cases which include the position of the active plane G17 to G19 (circular plane, helical
axis, infeed motion perpendicular to the active plane), any active rotating FRAME is taken
into account.
Length of the approach straight line or radius for approach circles (DISR)(see figure when
selecting approach/retraction contour)
• Approach/retract with straight line
• Approach/retraction with circles
Distance of the point from the machining plane (DISCL) (see figure when selecting
approach/retraction contour)
If the position of point P
perpendicular to the circle plane, the value must be programmed in the form DISCL=AC(...).
The following applies for DISCL=0:
• With G340: The whole of the approach motion now only consists of two blocks (P
• With G341: The whole approach contour consists of three blocks (P
• The point defined by DISCL is monitored to ensure that it is located between P
8-48
DISR specifies the distance of the cutter edge from the starting point of the contour, i.e.,
the length of the straight line when TRC is active is the sum of the tool radius and the
programmed value of DISR. The tool radius is only taken into account if it is positive.
The resultant line length must be positive, i.e., negative values for DISR are allowed
provided that the absolute value of DISR is less than the tool radius.
DISR indicates the radius of the tool center point path. If TRC is activated, a circle is
produced with a radius that results in the tool center point path with the programmed
radius.
is to be specified by an absolute reference on the axis
2
and P are combined). The approach contour is formed by P
3
combined). If P and P
0
from P to P is omitted).
1 3
i.e., the sign must be identical for the component perpendicular to the machining plane in
all motions that possess such a component.
to P is shown in the adjacent image.
0 4
are on the same plane, only two blocks result (infeed movement
4
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
, P
1
to P .
1 4
and P are
2 3
and P
1
Fundamentals
2
,
3