Driving systems Ball and roller screw
Figure 1
SKF ball & roller screw assemblies are high-quality products, suitable for a wide range of applications where precision driving systems are needed (➔ figures 1 and 2). The high efficiency screw affords the opportunity to displace loads by transforming rotary action into linear motion. The high efficiency screw has rolling elements, balls or rollers, between the nut and the screw shaft. In all types of ball screws, the load is transmitted from the screw shaft to the nut through each ball: several recirculating systems are available. To improve positioning accuracy, backlash can be reduced or eliminated (➔ figure 3). Two non-competing designs to cover requirements beyond ball screw limitations. Load transfer from the nut to the screw shaft through a number of threaded or grooved rollers: resulting in a large number of strong contact points (➔ figure 4).
Figure 2
3
Figure 3
Operating precision (➔ Table 1) Comparison of the different positioning components and systems.
Figure 4
NB: In addition to this catalogue we have all product brochures available as pdf document on the internet. www.linearmotion.skf.com/doc
Table 1
© SKF 2005
Positioning systems
Standard drives or linear motors with all guiding systems
Linear motors
Ball screws
Roller screws
Actuation systems
Electro-mechanical actuators
100 – 1000
Cam roller guides
10 – 100
Linear ball bearings
1 – 10
Profile rail guides
0.1 – 1
Driving systems
Standard slides
Guiding systems
Precision rail guides
Operating precision (µm)
103