RU178 G/X Crossed Cylindrical Roller Bearings |machine Tool Bearings 115*240*28mm

RU178 Cross roller bearing used for robot and machine tools(Integrated Inner/Outer Ring Type)

Since the mounting holes are provided,  RU178 does not require a presser flange or housing.  In addition, because it has an integrated inner/outer

 ring structure and is equipped with washers, its performance is minimally affected by the mounting  procedure, ensuring stable rotation accuracy

 and torque. This model can be used for both inner-ring rotation and outer-ring rotation.

 THK RU series the style No as below: RU85 RU124G(X)  RU148G(X)   RU178 G(X)  RU228G(X) RU297G(X)  RU445G(X) 

Structure features of   RU178 :

With the Cross Roller Ring, cylindrical rollers are arranged crosswise, with each roller perpendicular to the adjacent roller, in a 90°V groove, separated from each other by a spacer retainer.  This design allows just one bearing to receive loads in all directions including, radial, axial and moment loads. Since the Cross-Roller Ring achieves high rigidity and the precision can reach up to P4.P2,despite the minimum possible dimensions of the inner and outer rings,it is optimal for applications such as joints and swiveling units of industrial robots, swiveling tables of machining centers, rotary units of manipulators, precision rotary tables, medical equipment, measuring instruments and IC manufacturing machines.

Rotation accuracy

The spacer in  RU178  retainer fitting among crossarrayed rollers prevents rollers from skewing and the rotation torque from increasing due to friction between rollers. Unlike conventional types using steel sheet retainers, the Cross- Roller Ring does not cause displacement or locking of rollers and provides a stable rotation torque. Since the inner and outer rings are designed to be separable, the bearing clearance can be adjusted. In addition, highly accurate rotary motion is ensured through adjusting the bearing clearance to provide a preload.

Usage characteristics

The inner and outer rings of    RU178  , which are separable, are secured to    RU178  Cross Roller Ring body after the rollers and spacer retainers are installed. This procedure prevents the rings from separating from each other.  Thus, it is easy to handle the rings when installing the Cross-Roller Ring. The spacer retainer keeps rollers in their proper position,thereby preventing them from skewing.This eliminates friction between rollers, and therefore secures a stable rotation torque. the cross array of rollers allows a single Cross-Roller Ring unit to receive loads in all directions, increasing the rigidity to three to four times greater than the conventional type.