HEIDENHAIN TNC 426B (280 472) ISO programming - Manual (Page 39)

23 HEIDENHAIN TNC 410, TNC 426, TNC 430
Traversing the reference points in tilted axes
With tilted axes, you use the machine axis direction buttons to
cross over the reference points. The TNC interpolates the
corresponding axes. Be sure that the function for tilting the working
plane is active in the Manual Operation mode and the actual angle
of the tilted axis was entered in the menu field.
After you have positioned the rotary axes, set the datum in the
same way as for a non-tilted system. The TNC then converts the
datum for the tilted coordinate system. If your machine tool
features axis control, the angular values for this calculation are
taken from the actual position of the rotary axis.
You must not set the datum in the tilted working plane if
in machine parameter 7500 bit 3 is set. If you do, the
TNC will calculate the wrong offset.
If your machine tool is not equipped with axis control,
you must enter the actual position of the rotary axis in
the menu for manual tilting: The actual positions of one
or several rotary axes must match the entry. Otherwise
the TNC will calculate an incorrect datum.
Datum setting on machines with rotary tables
The behavior of the TNC during datum setting depends
on the machine.Your machine manual provides more
detailed information.
The TNC automatically shifts the datum if you rotate the table and
the tilted working plane function is active.
MP 7500, bit 3=0
To calculate the datum, the TNC uses the difference between the
REF coordinate during datum setting and the REF coordinate of the
tilting axis after tilting. The method of calculation is to be used
when you have clamped your workpiece in proper alignment when
the rotary table is in the 0° position (REF value).
MP 7500, bit 3=1
If you rotate the table to align a workpiece that has been clamped in
an unaligned position, the TNC must no longer calculate the offset
of the datum from the difference of the REF coordinates. Instead of
the difference from the 0° position, the TNC uses the REF value of
the tilting table after tilting. In other words, it assumes that you
have properly aligned the workpiece before tilting.
Position display in a tilted system
The positions displayed in the status window
(ACTL. and NOML.) are referenced to the tilted
coordinate system.
Limitations on working with the tilting function
■ The touch probe function Basic Rotation cannot
be used.
■ PLC positioning (determined by the machine tool
builder) is not possible.
■ Positioning blocks with M91/M92 are not
permitted.
2.5
Tilt the w
o
rking
plane
(not
TNC 41
0)
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