ETA+ Ball Screws
The innovative "ETA+" ball screw from Steinmeyer comes very close to providing the ideal linkage between motor and slide. From the reduced friction and at the same time increased stiffness results a significant improvement in efficiency. A 50% increase in rigidity and a 67% decrease in friction is accomplished. And reversing error has been eliminated altogether, which means that the ETA+ ball screw has a perfectly linear behavior regardless of speeds and direction of motion. This performance break-through is easily demonstrated with ball-bar tests, where the "quadrant changing" error is reduced to a fraction of the value achieved with conventional ball screws.
A bonus side effect of the dramatic reduction in friction is reduced heat generation, allowing machine builders to eliminate their costly and troublesome forced cooling systems. All users will welcome the reduced noise that is another characteristic of ETA+. It even outperforms ball chain technology. And the reduced friction yields significantly higher lifetime.
An additional and important fact - incorporating ETA+ requires no mechanical design changes. Many existing ball screws can be easily replaced with ETA+ since the outside dimensions remain the same. The only change required is a thorough re-turning of the servo in order to fully benefit from the superior control behavior of ETA+.