HEIDENHAIN TNC 620 (340 56x-03) Cycle programming - Manual (Page 430)

430 Touch Probe Cycles: Automatic Kinematics Measurement
1
8
.4 MEA
S
URE KINEMA
TICS (Cy
c
le
451, DIN/ISO: G451; Option)
Backlash
Backlash is a small amount of play between the rotary or angle
encoder and the table that occurs when the traverse direction is
reversed. If the rotary axes have backlash outside of the control loop,
for example because the angle measurement is made with the motor
encoder, this can result in significant error during tilting.
With input parameter Q432, you can activate backlash measurement.
Enter an angle that the TNC uses as traversing angle. The cycle will
then carry out two measurements per rotary axis. If you take over the
angle value 0, the TNC will not measure any backlash.
The TNC does not perform an automatic backlash
compensation.
If the measuring circle radius is < 1 mm, the TNC does not
calculate the backlash. The larger the measuring circle
radius, the more accurately the TNC can determine the
rotary axis backlash (see also "Log function" on page 436).
Backlash measurement is not possible if an M function for
positioning the rotary axes is set in machine parameter
mStrobeRotAxPos or if the axis is a Hirth axis.