HEIDENHAIN TNC 320 User Manual page 353

15.12 DATUM AT CENTER OF
4 HOLES (Cycle 418,
DIN/ISO: G418)
Cycle run
Touch Probe Cycle 418 calculates the intersection of the lines
connecting opposite holes and sets the datum at the intersection. If
desired, the TNC can also enter the intersection into a datum table or
preset table.
1 The TNC positions the touch probe at rapid traverse (value from
column FMAX) following the positioning logic (see "Executing
touch probe cycles" on page 285) to the center of the first hole 1.
2 Then the probe moves to the entered measuring height and
probes four points to find the first hole center.
3 The touch probe returns to the clearance height and then to the
position entered as center of the second hole 2.
4 The TNC moves the touch probe to the entered measuring height
and probes four points to find the second hole center.
5 The TNC repeats steps 3 and 4 for the holes
6 Finally the TNC returns the touch probe to the clearance height and
processes the determined datum depending on the cycle
parameters Q303 and Q305 (see "Saving the calculated datum"
on page 314). The TNC calculates the datum as the intersection of
the lines connecting the centers of holes
actual values in the Q parameters listed below.
7 If desired, the TNC subsequently measures the datum in the touch
probe axis in a separate probing.
Parameter number Meaning
Q151 Actual value of intersection point in
reference axis
Q152 Actual value of intersection point in
minor axis
HEIDENHAIN TNC 320
3 and 4.
1/3 and 2/4 and saves the
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