Rotary Stroke Bearings

A full line of Rotary Stroke Bearings is available from Mahr Federal. Suitable for a wide range of applications where linear, rotary, and combined movements are required, MarMotion high precision linear or Rotary Stroke Bearings are frequently specified for high precision applications such as machine tool spindles and pick-and-place assembly robots used in semi-conductor manufacture. MarMotion bearings have even been used on the Hubble telescope.

Originally developed by Mahr in order to increase the measuring accuracy and certainty of its dimensional metrology products, MarMotion high-precision rotary stroke bearings are used in measurement transducers, positioning units, centering and tilting tables, and in other modules that have an influence on the measuring result. MarMotion high-precision rotary stroke bearings exhibit virtually no backlash, stick slip or wear, and their motion is exceptionally smooth and reproducible.

Other popular applications for MarMotion Rotary Stroke Bearings include uses such as components in packaging machines in a wide range of industries, in automatic assembly units, textile machines, and high-quality special-purpose machines. MarMotion bearings are used in optical engineering to enable stick-slip-free movement of lenses, mirrors and diaphragms, and are suited for both large and heavy optical elements as well as for miniature design in small objectives.

In precision engineering applications where miniaturization requires compact instruments, MarMotion MINI series rotary stroke bearings provide stick-slip freedom, easy movement and maintenance-free operation. Small ball diameters reduce installation space, and 'Minis' come paired without play for components including small control elements for placer heads and laser welding technology, as well as blade holders, jigs or fixtures. MarMotion high-precision rotary stroke bearings assure high guiding accuracy for both linear and rotary movements.

The size and form accuracy (roundness and cylindricity) of the micro-finished running faces of shafts and bushings is less than ¹⁄₃ ISO standards; and only grade 5, sorting class P0 steel balls (DIN 5401 or ISO 3290) are used. Factory-preloaded balls and a low coefficient of friction virtually eliminate backlash and ensure smooth operation. The extensive range of MarMotion high-precision rotary stroke bearings offers appropriate solutions for many different applications.

Options include various thread combinations of guide shafts; closed or open guide bushes with or without stop rings; sealing rings or wipers; and plastic or brass ball cages with ceramic or stainless steel balls. Mahr can also manufacture special designs for particular applications and requirements, or use alternative materials.