RB (ERBC) Standard Cross Roller Bearing

RB (ERBC) series cross roller bearing is the basic model of crossed roller bearing. It has a separable outer ring and a united inner ring. So it is widely used for inner ring accuracy rotation. Model RB is the basic type of crossed roller bearings. The outer ring is divided into two pieces, and the inner ring is an integral structure, which is most suitable for occasions that require the rotation accuracy of the inner ring.

The outer ring of this type of bearing is divided into two parts in the axial direction and the inner ring as a whole; the cylindrical rollers are arranged in two 90°V-shaped raceways at a 90° included angle of 1:1, and the cylindrical rollers are separated by spacers.  In the future, this kind of bearing has a compact structure, so that a set of bearings can bear radial load, axial load and overturning load at the same time, while ensuring structural rigidity, greatly simplifying the design of the shafting structure; Can be pre-loaded to further facilitate installation and maintenance work. 

At the same time, this type of bearing has the characteristics of High precision, High load and High rigidity, which is very suitable for robot rotating parts, manipulator joint parts, CNC indexing workbenches, medical equipment, and measuring instruments It is especially suitable for the parts that require the rotation accuracy of the inner ring.

1. Runout accuracy of crossed roller bearings

Bearing runout can be divided into synchronous runout and asynchronous runout. The impact of synchronous runout on the overall runout of the worktable can be reduced to the greatest extent by grinding the work surface, but the impact of asynchronous runout cannot be eliminated in this link. , It is mainly determined by the outer diameter tolerance and roundness of the roller. Therefore, the better the control of the bearing asynchronous runout, the smaller the final radial and axial runout of the worktable, that is, the higher the running accuracy. When selecting bearing brands and accuracy grades, it is recommended not to only focus on the bearing assembly runout, but to have a thorough understanding of the accuracy standards that affect the asynchronous run out of the bearing.

2. Cross roller bearing fit

It is recommended that the inner ring and the shaft, and the outer ring and the gear ring are tightly matched when selecting the bearing. Since the outer ring is a rotating part, the tight-fitting amount should be slightly larger; the inner ring will be pressed down by the end cap to adjust the maximum pre-tightening amount, so the tight-fitting amount should be slightly smaller. However, if the inner ring is considered to be a stationary component, and the inner ring and the shaft are designed as a loose fit (there is a radial gap between the inner ring and the shaft), it may be possible to install the inner ring, lock the inner ring or when the bearing is loaded. The circle is skewed, that is, eccentricity occurs. This eccentricity will cause stress concentration on the boundary of the contact area between the roller and the raceway, causing serious scratches, cratering and peeling, and ending the bearing life earlier.

3. Shape and position tolerance

The mounting surface of the shaft and the ring gear is required to have the same flatness, perpendicularity, roundness and cylindricity as the precision bearing. Controlling these shape and position tolerances can not only achieve better assembly accuracy, but also avoid excessive eccentricity of the inner and outer rings of the bearing to cause stress concentration, and extend the service life of the bearing. Regarding the processing standards of the form and position tolerances, it is recommended to consult the bearing supplier and match its bearing accuracy.

Product process and test:

1. Surface: Make sure that the machine is cooled, control the surface bending and parallel difference. Pickling flaw detection for the first product to see whether there is burning damage or crack.

2. Outer ring: Control ellipse, triangle and size. repeated grinding if it is high.

3. Inner ring: Control ellipse, wall thickness and taper. The vertical difference should meet the requirements if it is high.

4. Raceway: Because of the particularity of this product, it needs to grind at a fixed distance and ensure that cooling is in place.

Standard models of RB series crossed roller bearing:

Catalog

As a professional manufacturer of bearings, we also provide custom service.

Package: plywood case with test reports and qualified certificates.