Four Support Methods of Ball Screw

Ball screw is an ideal product that converts rotational motion into linear motion or vice versa. It is the most commonly used transmission component in machine tools and precision machinery, mainly serving to convert rotational motion into linear motion or torque into axial reciprocating force, while possessing high precision, reversibility, and efficiency characteristics.

The ball screw consists of a screw, nut, steel balls, preload sheets, reverser, and dustproof device. Its function is to convert rotational motion into linear motion, which is an extension and development of the Acme screw. The significant significance of this development is to transform bearings from sliding action to rolling action. Due to its minimal frictional resistance, ball screws are widely used in various industrial equipment and precision instruments.

The working principle of the ball screw is to utilize the rolling of the steel balls between the screw and the nut to transmit motion and force. When the screw rotates, the steel balls roll in the helical grooves of the screw and nut, causing the nut to move axially along the screw. This rolling friction is much smaller than traditional sliding friction, hence ball screws have higher efficiency and longer service life.

The advantages of ball screws include high precision, efficiency, reliability, long lifespan, and low maintenance costs. They are suitable for applications requiring high-precision positioning and high-speed linear motion, such as CNC machine tools, automated equipment, precision measurement instruments, etc.

However, ball screws also have some disadvantages, such as high manufacturing costs, high requirements for operating environments, and the need for regular maintenance and upkeep. Therefore, when selecting ball screws, comprehensive consideration should be given to the specific application scenarios and requirements.

There are four types of support methods for ball screws:

One end fixed, one end free:Features: Simple structure, low axial stiffness, and poor stability for low critical speed screws. Mostly used for short strokes and vertical transmission. One end combines angular contact bearings, and the other end is free.

One end fixed, one end supported:The most typical and commonly used installation method of the ball screw mechanism is suitable for medium-speed, stiffness, and precision applications. The support end has slightly lower rigidity. One end combines angular contact bearings, and the other end is a deep groove ball bearing.

Both ends supported:Suitable for general occasions where medium speed, stiffness, and precision are not high. This form has a simple structure, low rigidity, poor force conditions, and fewer applications. Both ends are equipped with deep groove ball bearings.

Both ends fixed:Can withstand higher axial loads, and the axial stiffness of the screw is about 4 times higher than that of the one end fixed and one end supported installation method. Suitable for high-speed rotation, high precision, and long screw length occasions. This installation method also has drawbacks such as complex structure and sensitivity to thermal deformation of the screw. Both ends are equipped with combined angular contact bearings (DT-DB grouped configuration installation).