The concept and design of ball screws can be traced back to the late 19th and early 20th centuries. During the industrial revolution, with the development of the machinery industry, people's demand for linear motion became more and more urgent. Previously, a combination of a screw and nut was commonly used to achieve linear motion, but friction and imprecise properties limited the accuracy and efficiency of the system. In this context, the ball screw was proposed and developed. Ball screws utilize the rolling relationship between the balls and the screw, resulting in low friction and precise linear motion. In the design of the ball screw, the balls are arranged on the threaded track of the screw. When the screw rotates, the balls roll on the track, converting the rotary motion into linear motion. The introduction of the ball screw has greatly improved the performance of the linear transmission system, increasing the efficiency, stiffness and precision of the transmission. They are widely used in various fields, such as machine tools, robots, automated production equipment, stage lighting systems, printing machinery, etc., providing these systems with high precision, high speed and reliable linear motion. With the continuous advancement of science and technology and manufacturing technology, the design and manufacture of ball screw are also continuously improved and optimized. Modern ball screws have achieved higher load capacity, longer service life, higher stiffness and better reliability. They have become essential key elements in many mechanical systems, providing important support for industrial automation and production.

Trapezoidal screw: Pure sliding friction - brass (good self-lubrication) has a very low efficiency of 60%, a simple structure, low cost and no precision, large surface contact load, large starting resistance, resulting in creeping and creeping during ultra-low speed operation. Trapezoidal screws can be selected when there is no precision requirement, a large axial load is required, the budget is low and the cost needs to be reduced, the speed is low, and the occasion is not important. Ball screw: It realizes high-efficiency and low-friction transmission through rolling media, with an efficiency of more than 90%. Compared with surface contact, ball is point contact, with smaller load, higher precision and higher cost. The speed of the screw is limited, and it is best to control it within 1500rpm. If the screw is too long, it needs to be pressed down to within 1000rpm. Unit movement of the screw: lead (pitch, Pb) [Fixed seat]: Angular contact bearings are used in pairs to constrain the axial direction of the screw and are mainly used to bear the axial force of the screw [Support seat]: Deep groove ball bearings are used alone, purely to support the tail of the screw, so that it does not run around and can slide axially [Fixed + Support]: The most classic structure [Fixed + Free]: There is no way to put it, there is no place to install the support seat (short stroke, structural requirements), the speed cannot be too high, and the load should not be too large [Fixed + Fixed]: Not suitable for high-speed operation, heating will cause the screw to deform and get stuck, very good rigidity, high precision [Support + Support]: No precision, loose mechanism, small load, almost no requirements for motion performance---hand-cranked adjustment mechanism Nut structure of ball screw [External circulation]: Better high-speed performance, complex structure, higher cost [Internal circulation]: Slightly lower cost, more compact structure, easy to install Ball Screw precision C0 C1 .......C7 C10 ... The larger the number, the worse the accuracy and the lower the cost The screw rods of C7 and later are processed by extrusion molding --- rolled screw rods: high production efficiency----cheap, short delivery time The screw rods of C5 and earlier are processed by whirlwind milling + grinding --- ground screw rods: low production efficiency---very expensive, high accuracy The most used: C7 Ball Screw Preload Effectively prevent the nut seat from offsetting due to clearance when the load is large (improve the dynamic accuracy of large loads) Increases internal stress, greater resistance, and increased heat generation