Circular path ctp with tangential connection, Helical interpolation, Circular arc ctp – HEIDENHAIN iTNC 530 (340 422) User Manual
Page 213: Polar radius, polar angle of the arc end point, Combination of a circular and a linear movement, 5 p a th cont ours—p o lar coor dinat e s
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HEIDENHAIN iTNC 530
213
6.5 P
a
th Cont
ours—P
o
lar Coor
dinat
e
s
Circular Path CTP with Tangential Connection
The tool moves on a circular path, starting tangentially from a
preceding contour element.
8
Polar coordinates radius PR:
Distance from the arc
end point to the pole CC
8
Polar coordinates angle PA:
Angular position of the
arc end point
Example NC blocks
Helical interpolation
A helix is a combination of a circular movement in a main plane and a
linear movement perpendicular to this plane.
A helix is programmed only in polar coordinates.
Application
Large-diameter internal and external threads
Lubrication grooves
Calculating the helix
To program a helix, you must enter the total angle through which the
tool is to move on the helix in incremental dimensions, and the total
height of the helix.
For calculating a helix that is to be cut in an upward direction, you need
the following data:
12 CC X+40 Y+35
13 L X+0 Y+35 RL F250 M3
14 LP PR+25 PA+120
15 CTP PR+30 PA+30
16 L Y+0
The pole CC is not the center of the contour arc!
X
Y
40
35
CC
30°
120°
R30
R25
Thread revolutions n
Thread revolutions + thread overrun at
thread beginning and end
Total height h
Thread pitch P times thread revolutions n
Incremental total
angle IPA
Number of revolutions times 360° + angle for
beginning of thread + angle for thread
overrun
Starting coordinate Z
Pitch P times (thread revolutions + thread
overrun at start of thread)
Y
X
Z
CC