Ball splines are linear motion components with numerous balls integrated into the shaft, serving as mechanical elements that enable axial linear movement while transmitting rotational torque. Used in machine tool spindles, NC lathe main shafts, and automation equipment actuators, they are ideal for applications requiring high-precision positioning combined with rotational force transmission. Major manufacturers like THK, NSK, and IKO offer various sizes and precision grades. Unlike ball screws and linear guides, ball splines are positioned as specialized linear motion components that achieve combined rotational and linear motion. Their load-bearing performance and smooth operating characteristics have led to expanded adoption in high-speed, high-precision machining equipment.