thk ssr20xw linear motion guide for cnc
Structure and Features
Balls roll in four rows of raceways precision-ground on an LM rail and an LM block, and endplates
incorporated in the LM block allow the balls to circulate.
Since retainer plates hold the balls, they do not fall off even if the LM rail is pulled out (except models HSR 8, 10 and 12).
Each row of balls is placed at a contact angle of 45 so that the rated loads applied to the LM block
are uniform in the four directions (radial, reverse radial and lateral directions), enabling the LM
Guide to be used in all orientations. In addition, the LM block can receive a well-balanced preload,
increasing the rigidity in the four directions while maintaining a constant, low friction coeffi cient. With
the low sectional height and the high rigidity design of the LM block, this model achieves highly accurate and stable straight motion.
[4-way Equal Load]
Each row of balls is placed at a contact angle of 45 so that the rated loads applied to the LM block
are uniform in the four directions (radial, reverse radial and lateral directions), enabling the LM
Guide to be used in all orientations and in extensive applications.
[High Rigidity Type]
Since balls are arranged in four rows in a well-balanced manner, a large preload can be applied and
the rigidity in four directions can easily be increased.
[Self-adjustment Capability]
The self-adjustment capability through front-to-front configuration of THK’s unique circular-arc
grooves (DF set) enables a mounting error to be absorbed even under a preload, thus to achieve
highly accurate, smooth straight motion.
[High Durability]
Even under a preload or excessive biased load, differential slip of balls does not occur. As a result,
smooth motion, high wear resistance, and long-term maintenance of accuracy are achieved.
[Stainless Steel Type also Available]
A special type which LM block, LM rail and balls are made of stainless steel is also available.
