a coordinate measuring machine having a belt drive unit for an elongated axis element of the cmm , the belt drive unit comprising a belt , the ends of which are clamped on the elongated axis element , a pulley unit , comprising a drive pulley and two idler pulleys , wherein the belt entangles the drive pulley and the idle pulleys in an omega - shaped manner , and wherein the pulley unit is configured to cause a relative linear movement between the axis element and the pulley unit , wherein a damping layer is disposed adjacent to the belt .