Thin Film Sensors for Condition Monitoring in Ball Screw Drives

The development of sensor pins which can be easily integrated into ball screw drives for preload measurement is described in this paper. The sensor’s base body consists out of a steel pin with a special shaped load region. This complex surface is coated and structured with a sensory thin film system based on a hydrogenated carbon layer. The layer shows an excellent tribological stability combined with piezoresistive behaviour. It is shown, that the sensor pins can be used for preload measurements during the mounting and for dynamic load detections during the movement of the ball screw drive. Hence, measurement results are presented, that show the dependency of resistance changes to the preload forces.