In the Linear Motion Roller, dual rollers assembled on the circumference of the precision-ground, rigid raceway base travel in infinite circulation while being held by a retainer. A center guide integrated with the raceway base is formed in the central part of the loaded area of the raceway base to constantly correct skewing of the rollers. This unique structure ensures smooth rolling motion. The Linear Motion Roller is used in applications such as the XYZ guide of NC machine tools, precision press ram guides, press dies changers and heavy-load conveyance systems.
The Linear Motion Roller is compact and capable of carrying a heavy load, and one unit of model LR50130 (length: 130 mm; width: 82 mm; height: 42 mm) is capable of receiving a 255 kN load. Moreover, because of rolling motion, this model has a low friction coefficient (μ= 0.005 to 0.01) and is free from stick-slip, thus achieving highly accurate straight motion.
In general, when supporting a single plane with Linear Motion rollers, multiple units of Linear Motion rollers are combined on the same plane, and therefore, the height difference between the rollers significantly affects the machine accuracy and service life. With THK Linear Motion Roller, the user can select a combination of models with a height difference of up to 2μm.
With an Linear Motion system using rollers, once the rollers skew, it increases friction resistance or decreases running accuracy. To prevent skewing, the Linear Motion Roller has roller guides on the center of the retainer full circle, and in the center of the loaded area on the raceway base. This structure enables the Linear Motion Roller to automatically correct skewing caused by a mounting accuracy error and the rollers to travel in an orderly manner. It also allows the Linear Motion Roller to be installed with slant mount or wall mount while demonstrating high performance.
