Measuring the thermal extension in spindles

eddyNCDT SGS4701

The displacement measurement system SGS 4701 (Spindle Growth System) has been developed for high speed milling machine applications. Due to high machining speeds and the heat generated, the linear thermal extension of the precision machine tool spindle needs to be compensated for in order to keep the tool in a defined position at all times. The SGS sensor measures the thermal and centrifugal force extension of the spindle. The measurement takes places typically on the labyrinth-ring. As well as measuring linear thermal extension, the temperature of the sensor is also detected and output.These measurement values are fed into the CNC machine tool as correction values, compensating for any positioning errors.

  • Non-contact and wear-free measurement
  • Cost-effective design
  • Miniature sensor and controller, entirely integrable into spindle
  • Calibration for ferromagnetic and non-ferromagnetic
  • Integrated temperature measurement in the sensor
  • Extreme temperature stability

Compact structure

The SGS 4701 consists of a sensor, a sensor cable and a controller, factory calibrated for ferromagnetic and non-ferromagnetic measurement objects. Two miniature sensors enable it to be installed directly in the spindle. The compact controller can be installed on the spindle housing via a flange or directly in the spindle.

Robust design

The SGS 4701 operates on the eddy current measuring principle. This non-contact measurement is wear-free. Furthermore, the measurement procedure is resistant to disturbances such as heat, dust and oil.

8120 Brownleigh Dr.
Raleigh, NC 27617
919 787 9707
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