Tool-geometry Measurement Measure tools with cool precision
Relatively high temperatures in main machine tool spindles, particularly with high-speed-cutting (HSC) machines, have an impact on the accuracy of exchanged tools and touch probes and result in considerable thermal expansion. But thermally inert Thermo-Lock® touch-probe shanks for probes from M&H Inprocess Messtechnik GmbH solve this problem and enable micron-precise on-machine tool-geometry measurements.
HSC machines are increasingly being used to achieve higher precision and better surfaces with quicker cutting. Meanwhile, measuring tool geometries on the machine with touch probes is state of the tool measurement art. However, heat generation in the main spindles of HSC machines creates a problem in meeting high precision requirements.
If conventional touch probes are exchanged from the relatively cool magazine into the heated spindle of an operating HSC or other high-precision machine—where temperatures in the range of 40°–45°C are reached, representing a temperature gradient of 20°C or more between magazine and spindle nose—the probe shanks warm up considerably. Thermal expansion of 12 µm or more can occur within a couple of minutes. Immediate calibration is not possible, nor is linear compensation in the control, because of uncertainty about actual local temperatures at any given moment.
Thermo-Lock shanks for M&H infrared IRP40.01 and radio-wave data-transmitting RWP38.41 touch probes, however, allow high-precision tool measurement even at these high heat gradients between magazine and spindle. The foundation of the Thermo-Lock shanks is made of materials that exhibit almost no thermal growth and are, in addition, extremely heat-insulating.
Thus, the thermally inert shanks expand by only 1 μm within three minutes of entering the spindle. Their heat-insulating capability does not make the dimensions of these shanks any different from those of standard shanks from M&H. The temperature-insensitive versions of the IRP40.01 and RWP38.41 probing systems are marked by the designation -TI. Both probes are available with HSK-E40, HSK-E50 or HSK-A63 shanks.
M&H Inprocess Messtechnik GmbH