HEIDENHAIN TNC 620 User Manual page 258

6
Programming contours
Path contours  Cartesian coordinates
6.4
CircleG02/G03/G05 with defined radius
The tool moves on a circular path with the radius R.
Direction of rotation
In clockwise direction: G02
In counterclockwise direction: G03
Without programmed direction: G05. The TNC traverses the
circular arc with the last programmed direction of rotation
Coordinates of the arc end point
Radius R (the algebraic sign determines the size of
the arc)
Miscellaneous function M
Feed F
Full circle
For a full circle, program two blocks in succession:
The end point of the first semicircle is the starting point of the
second. The end point of the second semicircle is the starting point
of the first.
Central angle CCA and arc radius R
The starting and end points on the contour can be connected with
four arcs of the same radius:
Smaller arc: CCA<180°
Enter the radius with a positive sign R>0
Larger arc: CCA>180°
Enter the radius with a negative sign R<0
The direction of rotation determines whether the arc is curving
outward (convex) or curving inward (concave):
Convex: Direction of rotation G02 (with radius compensation G41)
Concave: Direction of rotation G03 (with radius compensation G41)
The distance from the starting and end points of the
arc diameter cannot be greater than the diameter of
the arc.
The maximum radius is 99.9999 m.
You can also enter rotary axes A, B and C.
The TNC normally makes circular movements in
the active working plane. If you program circular
arcs that do not lie in the active working plane, and
at the same time rotate this movement, then the
TNC moves the tool in a spatial arc, which means a
circular arc in 3 axes.
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HEIDENHAIN | TNC 620 | ISO Programming User's Manual | 9/2016