HEIDENHAIN TNC 320 User Manual page 394

16.9 MEASURE INSIDE WIDTH
(Cycle 425, DIN/ISO: G425)
Cycle run
Touch Probe Cycle 425 measures the position and width of a slot (or
pocket). If you define the corresponding tolerance values in the cycle,
the TNC makes a nominal-to-actual value comparison and saves the
deviation value in a system parameter.
1 The TNC positions the touch probe at rapid traverse (value from
FMAX column) following the positioning logic (see "Executing
touch probe cycles" on page 285) to the starting point 1. The TNC
calculates the touch 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). The
first probing is always in the positive direction of the programmed
axis.
3 If you enter an offset for the second measurement, the TNC then
moves the touch probe (if required, at clearance height) to the next
starting point 2 and probes the second touch point. If the nominal
length is large, the TNC moves the touch probe to the second
touch point at rapid traverse. If you do not enter an offset, the TNC
measures the width in the exact opposite direction.
4 Finally the TNC returns the touch probe to the clearance height and
saves the actual values and the deviation in the following
Q parameters:
Parameter number Meaning
Q156 Actual value of measured length
Q157 Actual value of the centerline
Q166 Deviation of the measured length
Please note while programming:
Before a cycle definition you must have programmed a
tool call to define the touch probe axis.
394 Touch Probe Cycles: Automatic Workpiece Inspection