HEIDENHAIN TNC 335 Technical Manual - Manual (Page 253)

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TNC 360 9 Touch Probe 8/95
The feed rate in the normal direction (MP6230) is the resultant velocity at which the touch probe is
fed from the non-deflected to the deflected condition perpendicular to the contour and vice versa.
Normal direction
Apart from the oscillation amplitude, the feed rate in the normal direction also determines the
maximum scanning feed rate. If MP6230 is too low, the machine dynamics will be under-utilized and
the scanning feed rate will also be low. If MP6230 is too high the oscillation amplitude will be too
high. In this case the stylus will be seen to lift off from the contour (the stylus "taps" the surface of
the workpiece) and the scanning feed rate no longer increases.
The maximum stylus deflection is defined by machine parameter MP6240. MP6240 will depend on
the length of the stylus used. MP6240 defines the maximum travel by which the stylus retracts on
inside corners. If the touch probe is not "cleared" after the stylus backs out by the travel defined in
MP6240, the touch probe axis (e.g. Z) is retracted in the positive direction. Digitizing continues as
soon as the touch probe is cleared. If the input value is too small, the touch probe system may get
caught up in a repeated attempt to get out of an inside corner.
Machine parameter MP6260 defines an M function that stores technology data such as tool
dimensions, spindle speed, feed rate and certain M functions (e.g. M3, M13). A small program is
generated containing these technology data and the M functions determined by MP6250. If the
program with the digitized data is run in blockwise mode this program is run immediately after the
generated program, the technology data is taken over.
Machine parameter MP6260 determines whether an M90 is added to each NC block (see also
"Constant feed rate in corners with M90" in Section "Servo positioning of the NC axes".
Machine parameter MP6270 defines the output format of the digitized data, i.e. the number of
decimal places to which the coordinates are output.
MP6210 Number of oscillations per second in normal direction.
Input range 0 to 65.535 [1/s]
MP6230 Feed rate in normal direction
Input range: 0 to 10 000 [mm/min]
MP6240 Maximum deflection of stylus
Input range: 0 to 10.000 [mm]