HEIDENHAIN TNC 320 (340 55x-03) Touch Probe Cycles - Manual (Page 71)

HEIDENHAIN TNC 320 71
3.2 Pr
eset
ting aut
o
matically
DATUM FROM INSIDE OF RECTANGLE
(touch probe cycle 410, DIN/ISO: G410)
Touch probe cycle 410 finds the center of a rectangular pocket and
defines its center as datum. If desired, the TNC can also enter the
coordinates into a datum table or the preset table.
1 The TNC positions the touch probe at rapid traverse (value from
FMAX column) following the positioning logic (see “Running touch
probe cycles” on page 21) to the starting point
1. The TNC
calculates the probe starting points from the data in the cycle and
the safety clearance from the SET_UP column of the touch probe
table
2 Then the touch probe moves to the entered measuring height and
probes the first touch point at the probing feed rate (column F).
3 Then the touch probe moves either paraxially at the measuring
height or linearly at the clearance height to the next starting point
2 and probes the second touch point.
4 The TNC positions the probe to starting point 3 and then to starting
point 4 to probe the third and fourth touch points.
5 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 64)
6 If desired, the TNC subsequently measures the datum in the touch
probe axis in a separate probing and saves the actual values in the
following Q parameters.
X
Y
1
2
3
4
Parameter number Meaning
Q151 Actual value of center in reference axis
Q152 Actual value of center in minor axis
Q154 Actual value of length in the reference
axis
Q155 Actual value of length in the minor axis
Before programming, note the following
To prevent a collision between touch probe and
workpiece, enter low estimates for the lengths of the 1st
and 2nd sides.
If the dimensions of the pocket and the safety clearance
do not permit pre-positioning in the proximity of the touch
points, the TNC always starts probing from the center of
the pocket. In this case the touch probe does not return to
the clearance height between the four measuring points.
Before a cycle definition you must have programmed a
tool call to define the touch probe axis.