The decisive merit of this series of linear motion guides is seen in the deep circular arc grooves, the curvature of which corresponds approximately to the ball diameter. This is claimed to optimize the running performance during high stress situations. As the German company explains, high machining forces on the linear guide increase the ball contact surfaces to the running grooves. The resulting differential slip with an ideal proportion of sliding and rolling motion generates a load-dependent friction resistance, which significantly increases the damping characteristic and the load-bearing capacity of the linear guide. If, on the other hand, no machining forces are applied to the linear guide in rapid travel, it can be moved very easily. For improved protection against foreign particles and liquids, newly developed protectors and side wipers are available, which enable operation even under difficult environmental conditions. Depending on the load situation, the SVR/NR-X types can be selected for high radial loads or the SVS/NRS-X versions with evenly high load ratings in all main directions. All models are available in the usual market sizes of 25 to 65 as well as with one-piece rails up to 7,000 mm in length.
LM guides for machine tools with and without ball cage
The SVR/SVS caged-ball linear motion guides from THK have been extended by the full-spherical NR-X/NRS-X linear guides. With or without a ball cage, both models reportedly stand out through their high stiffness and optimized dynamic running performance.