HEIDENHAIN TNC 335 Technical Manual - Manual (Page 257)

4-160
TNC 360 9 Touch Probe 8/95
Inside Corners
Contour
PP
. INT
Travel
3
PP
. INT
1
4
2
Max. deflection
of stylus MP6240
5
6
On inside corners, having probed the last point
c the touch probe continues to oscillate in the same
scanning direction but changes direction because it cannot get clear. It then moves down the
resultant straight line until it either gets clear or hits one of the limits TRAVEL
e or PP.INT.e
The touch probe moves in inverse scanning direction to get clear. If the programmed probe point
interval PP.INT
f is too small for the probe to clear, it travels paraxially in negative direction by up to
the value of MP6240 (maximum stylus deflection). As soon as the touch probe is clear it returns to
the contour
g in the inverse travel direction. The new scanning direction is defined by the probed
points
c and g. If the touch probe has failed to clear even after it has backed out by the value of
MP6240
h, the touch probe axis (e.g. Z+) is cleared in the positive direction. If the stylus is still
deflected after it reaches the "clearance height" (see "Range" scanning cycle) the scanning sequence
is aborted and an error message is displayed.