The German geared motors and drives specialist Stober has unveiled a range of compact servo ballscrew motors that drive rotating spindles or spindle nuts directly. The dynamic, high-torque motors are based on Stober’s PipeDrive technology.

One version (type EZS) is designed to drive screw drives with a rotating screw shaft. The screw nut will usually be connected to a linear slide, which it drives. The screw is fixed by inserting it into the motor’s blind-hole hollow-shaft, and connecting it to a clamping set. Screws with four diameters from 20–40mm can be used, depending on the frame size. To absorb the high axial thrust, the EZS motors are fitted with special axial angular contact ball bearings.

The second version (type EZM) is aimed at screw drives with driven nuts. Its large flanged hollow shaft can drive flanged spindle nuts directly.

The motors achieve their short lengths by using an orthocyclic tooth winding system with a high copper fill factor, producing about 80% more power than a conventional winding. Both types are available in two sizes, three lengths and four spindle pitches (10–32mm). They can also be supplied as brake motors and with liquid cooling. Forced-cooling fans are available as an option for the EZS models.