Destruction-free, non-tactile measuring principles are common, but these mostly optical measuring methods cannot match the precision of tactile encoders with photoelectric scanning. The great challenge is the development of a measuring device that combines high accuracy with destruction-free measurement. HEIDENHAIN has solved this problem with its new METRO 1281 MW length gauge. It features an extraordinarily low measuring force curve between 0.01 N and 0.07 N over its entire 12 mm measuring range.
The new length gauge therefore provides access to new fields in tactile and high-accuracy metrology. Now it is possible, for example, to calibrate very small gears, various glass objects and wafers, or products in medical technology. This rules out the undesired deformation of workpieces by the measuring device that can falsify measuring results or even damage or destroy the workpiece. Transparent materials that repeatedly present difficulties for optical methods can likewise be measured simply and exactly with the METRO 1281 MW from HEIDENHAIN.
In addition to scanning, highly precise ball bearing guides are a further core component of the METRO 1281 MW. The interplay of ball bearing guides and high-precision photoelectric scanning achieves repeatability of less than 0.03 µm along the complete measuring path. The length gauge’s system accuracy lies within ±0.2 µm.
In addition to the low measuring force curve, the METRO 1281 MW also features Zerodur precision graduation with 2 µm signal periods. Zerodur has a thermal coefficient of expansion of almost 0 ppm/K in the 0 °C to 50 °C range, meaning that ambient temperature has effectively no influence on expansion of the scale. The METRO 1281 MW therefore always measures the true length.