New ball screws with interchangeable nut-shaft combinations

As high-precision drive elements, ball screws are always designed to customer specifications and adapted to a specific task. The manufacturer then supplies individual assemblies of nuts and shafts that have been matched in the factory to give the required preload.

At EMO, NSK, which describes itself as the world's largest manufacturer of precision ball screws, is introducing a new series which does not require using an individually matched nut-shaft combination. Instead, the nut and shaft can be freely interchanged, following the principle of random matching.

Based on the NSK BSS series for high-speed, low-noise applications, NSK's interchangeable balls screws are available in accuracy class C7. They come in shaft diameters from 15 to 32mm, with pitches from 5 to 20mm. The dimensions of the flange and mounting holes, as well as the tolerance classes, meet the requirements of DIN 69051 (ISO 3408). Optionally, the nut bodies can be equipped with an NSK K1 lubrication unit.

Thanks to their inherent design, the units are shipped with very little axial play as standard. If necessary, a desired preload can be generated by changing the size of the balls at a NSK dealer or directly at NSK.

The new series is intended for applications such as pick-and-place systems, and automated transfer units for assembly, handling and internal transport. Many other uses are also possible.

For users, the free interchange of nut and shaft has the advantage that the required ball screw can simply be taken or ordered from stock, and then cut to length either in-house or by an authorised NSK dealer. The result is greater flexibility for the user and the rapid availability of ball screws in individual dimensions, whenever they are needed for special machines or prototypes, for example.

NSK will be at EMO 2019 in Hall 7, Booth B34. Visit www.nskeurope.com for further information.