Ball screws are one of the many components seen throughout factory automation applications. Using the same concept seen with a bolt and nut, this assembly uses the rotary motion of the screw to actuate the nut in a linear direction.
A ball screw achieves its smooth linear motion by recirculating steel balls along the screw groove within the nut. The steel ball recirculation method differentiates the motion characteristics of the ball screw. Below we will explore the 4 main types of recirculation:
Methods 1, 2, and 3 are shown in much more detail in Figure 2.
Figure 2: In this figure we have three methods (In order of appearance): End Cap, Deflector, and Return Tube.
With a high level overview on the internal structure of ball screws, the concept of preloading will be easy to grasp. In the next article we will touch on preloading – the purpose and different methods.