101HEIDENHAIN TNC 426 B, TNC 430
Departing tangentially on a circular arc: DEP CT
The tool moves on a circular arc from the last contour point P
E
to
the end point P
N
. The arc is tangentially connected to the last
contour element.
ú Program the last contour element with the end point P
E
and
radius compensation.
ú
Initiate the dialog with the APPR/DEP key and DEP CT soft key:
ú Radius R of the circular arc
■
If the tool should depart the workpiece in the direction
of the radius compensation (i.e. to the right with RR or
to the left with RL):
Enter R as a positive value.
■
If the tool should depart the workpiece on the
direction opposite to the radius compensation:
Enter R as a negative value.
ú
Center angle CCA of the arc
Example NC blocks
23 L Y+20 RR F100
24 DEP CT CCA 180 R+8 F100
25 L Z+100 FMAX M2
Departing on a circular arc tangentially connecting
the contour and a straight line: DEP LCT
The tool moves on a circular arc from the last contour point P
E
to an
auxiliary point P
H
. It then moves on a straight line to the end point P
N
.
The arc is tangentially connected both to the last contour element
and to the line from P
H
to P
N
. Once these lines are known, the radius
R then suffices to completely define the tool path.
ú Program the last contour element with the end point P
E
and
radius compensation.
ú
Initiate the dialog with the APPR/DEP key and DEP LCT soft key:
ú Enter the coordinates of the end point P
N
.
ú
Radius R of the arc
Always enter R as a positive value
Example NC blocks
23 L Y+20 RR F100
24 DEP LCT X+10 Y+12 R+8 F100
25 L Z+100 FMAX M2
Last contour element: P
E
with radius compensation
Center angle=180°, arc radius=10 mm
Retract in Z, return to block 1, end program
Last contour element: P
E
with radius compensation
Coordinates P
N
, arc radius = 10 mm
Retract in Z, return to block 1, end program
X
Y
20
P
N
R0
P
E
RR
R8
180°
RR
X
Y
20
P
N
R0
P
E
RR
RR
12
10
R8
P
H
R0
6.3 Contour Approach and Departure
Gkap6.pm6 30.06.2006, 07:04101
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