When a piece of machinery or equipment requires the use of a functioning ball screw, the assembly and components need to work accurately. But sometimes, the ball screw assembly can experience what is known as backlash. This refers to the amount of play within the ball and nut of the assembly and can create excessive dysfunction and malfunction.
Here, we explain how to reduce or eliminate ball screw backlash to ensure your equipment maintains steady operation.
The problem with backlash is the total loss in motion within the ball nut, and this is due to an excessive amount of clearance per load between the ball and the tracking on the nut and screw. You may refer to backlash as play or lash, but backlash is its most accurate engineering phrasing.
If we dial in on this further, backlash is the lost movement in the axial direction. An example of this will be if the backlash receives a rating of .002″, which means that the ball nut can only move .002″ on a screw and not turn the screw effectively.
Ways To Reduce or Eliminate Backlash
One way to reduce the backlash is to preselect the ball sizing. This method would work best for decreased lead and diameter ratios. There are instances where preloading the ball nut is effective.
Another successful way to reduce or eliminate ball screw backlash is making the preload adjustable. This requires using two ball nuts and a spring assembly connecting them. A spring assembly will press the ball nuts to the corresponding ends of the screw’s track. A threaded ring will adjust the spring’s tension and enable an engineer to adjust the preload to the specific applications.
Why Backlash Is Bad
You want to address and correct your backlash issues because they can create positioning on the axis directional changes. The play in the gears and threads can stir up significant amounts of error through the axis positioning.
If your equipment throws a backlash in the ball screw assembly, reach out to Wedin International today! We are industry-leading ball screw manufacturers with over 40 years of experience and can accurately and promptly diagnose and address ball screw issues.