Polar Coordinate Origin: Pole Cc - HEIDENHAIN TNC 426 B User Manual

6.5 Path Contours—
Polar Coordinates
With polar coordinates you can define a position in terms of its
angle PA and its distance PR relative to a previously defined pole
CC. See section "4.1 Fundamentals of NC. "
Polar coordinates are useful with:
Positions on circular arcs
Workpiece drawing dimensions in degrees, e.g. bolt hole circles
Overview of path functions with polar coordinates
Function
Line LP
Circular arc CP
Circular arc CTP
Helical interpolation

Polar coordinate origin: Pole CC

You can define the pole CC anywhere in the part program before
blocks containing polar coordinates. Enter the pole in Cartesian
coordinates as a circle center in a CC block.
Coordinates CC: Enter Cartesian coordinates for the
pole, or:
If you want to use the last programmed position, do
not enter any coordinates.
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Path function keys Tool movement
+ Straight line
+ Circular path around circle center/
pole CC to arc end point
+ Circular path with tangential
connection to the preceding
contour element
+ Combination of a circular and a
linear movement
Required input
Polar radius, polar angle of the
straight-line end point
Polar angle of the arc end point,
direction of rotation
Polar radius, polar angle of the
arc end point
Polar radius, polar angle of the
arc end point, coordinate of the
end point in the tool axis
Y
CC
Y
CC
X
CC
6 Programming: Programming Contours
X