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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

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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), th
e 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.