The incremental displacement sensors are based on a magnetic principle: consisting of a magnetic scale and a multi-slot reading head that responds to changes in magnetic flux, they detect linear movements with high precision and resolution.
The scale of ferromagnetic alloy – or magnetic tape – is magnetized by an alternating magnetic field with a pole spacing of 0.2 mm. A special recording head and a laser measurement system guarantee that the graduations are very precise. From the magnetic pattern on the scale, the multi-slot reading head generates a signal proportional to the movement.
The analog signal generated by the reading head is electronically divided and digitized. Changes in length can be measured with a resolution of from 1 μm down to 0.1 μm.
Thanks to its slim shape with a diameter of 8 mm and its high accuracy over the full range of measurements, model 8738 DK is particularly suitable for use in multi-point measuring equipment. The spindle and spindle guide are protected from dust by a bellow.