What Are the Performance Characteristics of Ball Screws?

1. Know the ball screw

The ball screw consists of a screw, a nut, a steel ball, a pre-press, a reverser, and a dust filter. It is an ideal product for converting rotary motion into linear motion, or converting linear motion into rotary motion. When the linear ball screw is used as the active body, the nut will be converted into linear motion with the rotation angle of the screw according to the lead of the corresponding specification, and the passive workpiece can be connected by the nut seat and the nut to realize the corresponding linear motion.

2. The performance characteristics of the ball screw

The performance of the transmission mechanism: Compared with the sliding screw pair, the driving torque is 1/3. Since there are many balls rolling between the screw shaft of the ball screw pair and the ball nut, high motion efficiency can be obtained. Compared with the past sliding screw pair, the driving torque is less than 1/3, that is, the power required to achieve the same motion result is 1/3 of the rolling screw pair, which is very helpful in saving power.

High transmission efficiency: The transmission efficiency of the ball screw&nut assembly is as high as 90%~98%, which is 2 to 4 times that of the sliding screw pair, which can efficiently convert torque into thrust, or convert thrust into torque.

Sensitive and stable transmission: The ball screw pair is point-contact rolling friction, with small frictional resistance, good sensitivity, no chattering at startup, no creeping at low speed, and can achieve μm-level control of microfeed.

High positioning accuracy: The temperature rise during the transmission of the ball screw pair is small, the axial clearance and primary elastic deformation can be eliminated by preloading, and the linear lead screw can be prestretched to compensate for thermal elongation, so high positioning accuracy can be obtained. and repeat positioning accuracy.

Good accuracy retention: The ball and raceway hardness is up to HRC58 to 63, the raceway shape is accurate, the rolling friction and wear are extremely small, and it has good accuracy retention, reliability and service life.

High transmission rigidity: The inner and outer raceways of the ball screw pair are all eccentric corners with double arc surfaces, which can be flexibly transmitted even when the raceway clearance is extremely small. When necessary, a certain preload can be added to eliminate the axial play and primary elastic deformation to obtain good rigidity (the service life is reduced at this time).

Good synchronization performance: The ball screw pair has the characteristics of high lead accuracy and good sensitivity. When synchronous transmission is required, several sets of ball screw pairs with the same lead can be used to obtain good synchronization performance without backlash and rigidity. high. The ball screw pair can be pre-loaded. Due to the pre-load, the axial clearance can reach a negative value, thereby obtaining higher rigidity. When it is actually used in mechanical devices, etc., the rigidity of the nut part can be enhanced due to the repulsion of the balls.