Oil free liner and rotating ball spline

slides through the gap between the oil-free liner fixed on the fixed seat and the shaft, and achieves motion on two axes through linear motion in the direction of the paper and rotation around the direction of the paper as the central axis. On the other hand, the rotating ball spline utilizes a dual configuration of linear guide rolling elements and rotating direction rolling elements in the radial direction to achieve rotation and linear motion of the internal shaft relative to the fixed outer ring.
There are two differences between oil-free bushings and rotating ball splines, the first being the number of components. Comparing oil-free bushings and rolling bearings, it can be seen from Figure 1 that oil-free bushings have a simple structure with only three components including the fixed seat, making them cost-effective. In contrast, rolling bearings have a double-digit number of components, resulting in a proportional increase in cost. The second point is the difference in friction coefficient. Due to the higher friction coefficient of sliding bearings compared to rolling bearings, the force used to drive the rotating shaft in oil-free bearings is greater. When using oil-free bushings, the output power of the motor must be higher than that of the rolling bearings.
Ball spline pair is a precision linear motion functional component system, which is an extension and optimization of rectangular spline and involute spline. It is the result of replacing sliding friction with rolling friction, and achieves transmission positioning accuracy and function that cannot be achieved by rectangular spline and involute spline transmission. It is one of the functional components promoted and applied in the field of precision transmission today.
 
Ball screw is an ideal product for converting rotary motion into linear motion, or converting linear motion into rotary motion. A ball screw is composed of a screw, nut, and ball. Its function is to convert rotational motion into linear motion, which is a further extension and development of ball screws. The significance of this development is to transform bearings from rolling motion to sliding motion. Ball screws are widely used in various industrial equipment and precision instruments due to their low frictional resistance.