introduction to the principle of ball screw

ball screw has been widely used in all electric servo injection molding machine because of its high mechanical efficiency and high compliance performance. the ball screw is a motion pair that uses the ball as the power transmission interface between the screw and the nut to roll. ball screw is mainly developed for the purpose of machine tool driving device, and its development purpose is to achieve position accuracy and smoothness. ball screws have been successfully used in precision machinery, automation, various power transmission, semiconductor, medical and aerospace industries.
because the use and precision requirements of machine tools and injection molding machines are different, the design concepts of the ball screws are also different. table 1 shows the comparison of ball screws for machine tools and injection molding machines.
table 2 shows the comparison of various driving methods of the all electric ejection mechanism. it shows that the ball screw has a good performance in terms of efficiency, thrust, durability, response and cost evaluation. compared with the load borne by the screw when it is used on the machine tool, the load borne by the injection mechanism of the fully electric servo injection molding machine is hundreds or even thousands of times that of the general screw. the high load ball screw of shangyin technology came into being (as shown in the figure). because the stroke of the ejection mechanism is short and there are many unfavorable conditions in the lubrication position, in order to maintain the working performance of the injection molding machine for a long time, the design of high load ball screw focuses on homogenizing the ball surface pressure, reasonably arranging the lubrication position, and improving the load capacity and life.