Micro-Epsilon eddyNCDT SGS 4701 eddy current sensor

The Micro-Epsilon eddyNCDT SGS 4701 eddy current sensor is suitable for measuring the thermal extension of high-frequency spindles in order to minimise positioning errors in machine tools.

The spindle is at the heart of a machine tool and so plays a decisive role in the dimensional accuracy and surface quality of the respective workpiece. High speeds and the heat generated result in axial extension of the workpiece spindle and therefore to positioning error during finishing of the workpiece. The miniature sensor measures the thermal and centrifugal force extension of high-frequency spindles by measuring on the labyrinth ring. The measured values are fed into the CNC machine tool as correction values and compensate for any positioning errors.

The miniature eddy current sensors have dimensions of 4.5 x 10 x 12 mm³ or 4 x 4 x 10 mm³ and can be integrated with the controller into the machine tool spindle. For ease of handling and in order to achieve maximum accuracy, the device is factory calibrated for ferromagnetic and non-ferromagnetic materials used by the customer. The temperature of the sensor is measured via the resistance of the eddy current coil for temperature compensation. This signal is also available to the user, which can eliminate the need for any additional temperature-sensing technology.