2 a u to matic d at u m set ting – HEIDENHAIN TNC 426B (280 472) Touch Probe Cycles User Manual
Page 73
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HEIDENHAIN TNC 426, TNC 430
61
3.2 A
u
to
matic D
at
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m Set
ting
DATUM AT CENTER BETWEEN 4 HOLES
(touch probe cycle 418, ISO: G418)
Touch probe cycle 418 calculates the intersection of the lines
connecting opposite corners of a rectangle defined by four hole
centers. If desired, the TNC can also enter the intersection into a
datum table.
1
Following the positioning logic (see “Running touch probe cycles”
on page 7), the TNC positions the touch probe at rapid traverse
(value from MP6150 or MP6361) 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
3
and
4
.
6
Finally the TNC returns the touch probe to the clearance height and
sets the datum at the intersection of the diagonal lines connecting
opposite holes
1
/
3
and
2
/
4
or writes the coordinates of the
intersection to the active datum table.
X
Y
4
3
2
1
Before programming, note the following:
Before a cycle definition you must have programmed a
tool call to define the touch probe axis.