UltraSpeed ball screws feature two closed ball tracks, one for each thread of the double-start nut. UltraSpeed ball screws are available with either a single or pitch-offset preloaded nut.
Cutting machines offering traverse velocities in excess of 60 m/min place exceptional demands on ball screw drives. Series 34 and 35 'UltraSpeed' ball screws from Steinmeyer GmbH meet this challenge using multiple threads and a nut specifically designed for the high-speed market.
Series 34, for example, achieves preload in the same manner as conventional designs, via oversize balls. However, it also doubles the number of ball tracks in either load direction. This results in a considerably greater load capacity and higher degree of stiffness compared with single start thread designs.
Series 35 achieves preload via threads ground with pitch offset, as in a double nut or pitch-shift nut. Adjacent ball tracks, however, allow load carrying capacity in both directions. The shorter load path means more stiffness and the same size envelope as a conventional single unit.
Both 34 and 35 Series balls screws are suitable for DN values as high as 160,000. Considering a screw of 40 mm nominal diameter, a maximum speed of 4,000 rpm can be obtained. With the corresponding structure, it is possible to reach 1G accelerations or greater.
George Jaffe, Steinmeyer Inc., 11 DeAngelo Dr., Bedford, MA 01730; Tel: (781) 275-6097; Fax: (781) 275-4749; E-mail: [email protected] For more information, circle 509
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