The research of double-nut ball screw preload based on GMA

Ball screw is widely used in the fields of modern industry, aviation industry, automobile industry, etc., and has a greater impact on the development of the machine tool industry. Axial clearance between ball screw and nut will exist under the action of axial load which directly affects the accuracy or positioning accuracy. Therefore, to reduce or eliminate the axial clearance, preload between screw and nut is often applied to achieve zero clearance transmission. But traditional way of preload can't be real-time detection and control of preload. This paper intends to design a new double-nut ball screw preload structure based on GMA (Giant Magnetostrictive Actuator) to automatically adjust the preload. A GMA is designed according to requirements of ball screw, and a double-nut ball screw preload structure based on the GMA is designed. Testing experiment of GMA is done: current-displacement under no-load condition and current-output force under loading condition. Applying GMA to preload double-nut ball screw provides a theoretical and experimental basis for preload's real-time detection and control.