HEIDENHAIN TNC 426B (280 472) Touch Probe Cycles - Manual (Page 118)

106 3 Touch Probe Cycles for Automatic Workpiece Inspection
3.4 Special Cy
cles
MEASURE AXIS SHIFT (touch probe cycle 440,
ISO: G440, available as of NC software
280 476-xx)
Touch probe cycle 440 measures the axis shifts of the machine.
Make sure that the cylindrical calibrating tool used in connection with
the TT 130 has the correct dimensions.
1 The TNC positions the calibrating tool at rapid traverse (value from
MP6150 or MP6361) and following the positioning logic (refer to
chapter 1.2) in the vicinity of the TT.
2 At first the TNC makes a measurement in the touch probe axis.
The calibrating tool is offset by the value you have defined in the
tool table TOOL.T under TT: R-OFFS (standard = tool radius). The
TNC always performs the measurement in the touch probe axis.
3 Then the TNC makes the measurement in the working plane. You
define via parameter Q364 in which axis and in which direction of
the working plane the measurement is to be made.
4 If you make a calibration, the TNC saves the calibration data.
Whenever you make a measurement, the TNC compares the
measured values to the calibration data and writes the deviations
to the following Q parameters:
You can use this value for compensating the deviation through an
incremental datum shift (cycle 7).
5 Finally, the calibrating tool returns to the clearance height.
Prerequisites:
Before running cycle 440 for the first time, you must have
calibrated the tool touch probe with tool-touch-probe
cycle 30.
Ensure that the tool data of the calibrating tool has been
entered in the tool table TOOL.T.
Before running the cycle, you must activate the calibrating
tool with TOOL CALL.
Ensure that the TT tool touch probe is connected to input
X13 of the logic unit and is ready to function (machine
parameter 65xx).
Parameter number Meaning
Q185 Deviation from calibration value in X
Q186 Deviation from calibration value in Y
Q187 Deviation from calibration value in Z