3 cont our appr oac h and depar tur e – HEIDENHAIN TNC 620 (73498x-01) User Manual
Page 181
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HEIDENHAIN TNC 620
181
6.3 Cont
our appr
oac
h
and depar
tur
e
Departure on a circular path with tangential
connection: DEP CT
The tool moves on a circular arc from the last contour point P
E
to the
end point P
N
. The path is tangentially connected to the last contour
element.
U
Program the last contour element with the end point P
E
and radius
compensation
U
Initiate the dialog with the APPR/DEP key and DEP CT soft key:
U
Center angle CCA of the arc
U
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 in the
direction opposite to the radius compensation:
Enter R as a negative value
Example NC blocks
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
. The radius R uniquely defines the arc.
U
Program the last contour element with the end point P
E
and radius
compensation
U
Initiate the dialog with the APPR/DEP key and DEP LCT soft key:
U
Enter the coordinates of the end point P
N
U
Radius R of the circular arc. Enter R as a positive value
Example NC blocks
X
Y
20
P
N
R0
P
E
RR
R8 180°
RR
23 L Y+20 RR F100
Last contour element: P
E
with radius compensation
24 DEP CT CCA 180 R+8 F100
Center angle = 180°,
Arc radius = 8 mm
25 L Z+100 FMAX M2
Retract in Z, return to block 1, end program.
X
Y
20
P
N
R0
P
E
RR
RR
12
10
R8
P
H
R0
23 L Y+20 RR F100
Last contour element: P
E
with radius compensation
24 DEP LCT X+10 Y+12 R+8 F100
Coordinates P
N
, arc radius = 8 mm
25 L Z+100 FMAX M2
Retract in Z, return to block 1, end program.