HEIDENHAIN TNC 620 (340 56x-02) - Manual (Page 160)

160 Programming: Programming Contours
6.3 Cont
our Appr
oac
h
and Depar
tur
e
6.3 Contour Approach and
Departure
Overview: Types of paths for contour approach
and departure
The functions for contour approach APPR and departure DEP are
activated with the APPR/DEP key. You can then select the desired
path function with the corresponding soft key:
Approaching and departing a helix
The tool approaches and departs a helix on its extension by moving in
a circular arc that connects tangentially to the contour. You program
helical approach and departure with the APPR CT and DEP CT
functions.
Function Approach Departure
Straight line with tangential connection
Straight line perpendicular to a contour
point
Circular arc with tangential connection
Circular arc with tangential connection
to the contour. Approach and departure
to an auxiliary point outside the contour
on a tangentially connecting line.