Three ways of bearing cage guidance

As an important part of the bearing, the cage plays the role of guiding and separating the rolling elements. The guiding role of the cage actually refers to the correction of the operation of the rolling elements. This correction is achieved by the collision of the cage and the surrounding components.

There are three guiding modes of general bearing cages: rolling element guidance, inner ring guidance, and outer ring guidance.

 

Rolling Body Guidance:

The standard structure of the general design is the rolling element guidance, such as the short cylindrical roller bearing, the rolling element guidance, the cage and the flange surface of the inner and outer rings are not in contact, the cage can be universal, but when the rolling element speed increases at high speed, the rotation is unstable, so the rolling element guidance is suitable for medium speed and medium load, such as gearbox bearing, etc.

The bearing cage guided by the rolling elements is located in the middle of the rolling elements. There is no contact and collision between the cage and the inner and outer rings of the bearing, and the collision of the cage and the rollers corrects the roller movement, and at the same time separates the rollers in a certain equally spaced position.

 

Outer ring guidance:

The outer ring is generally stationary, and the outer ring guidance facilitates the lubricating oil to enter the guide surface and raceway. The high-speed gearbox is lubricated with oil mist, which is squeezed out by the rotating inner ring guidance. The outer ring-guided bearing cage is located on the side of the rolling element close to the outer ring, and when the bearing is running, the bearing cage may collide with the outer ring of the bearing and correct the cage position.

The outer ring guide is generally used for high-speed and stable load, taking the cylindrical roller bearing as an example, it only bears a fixed value of axial load, the speed of each rolling element does not change much when rotating, and the rotation of the cage is not unbalanced.

 

Inner ring guidance:

The inner ring is generally a rotating ring and provides a rolling element to drag the torque as it rotates, and slippage occurs if the bearing load is unstable or light.

And the cage adopts internal guidance, and the oil film is formed on the guiding surface of the cage, and the friction of the oil film is circled in the non-load area to give the cage a drag force, thereby increasing the additional driving torque of the cage to the rolling element, and can prevent slipping.

The inner ring-guided bearing cage is located close to the inner ring of the rolling elements, and when the bearing is running, the cage may collide with the inner ring of the bearing, thus correcting the cage position.

 

The three types of cage guidance can occur in different types of bearings, including performance reasons, as well as the design and manufacture of the bearing itself. Engineers can choose according to their needs. But sometimes engineers don't have a choice. In any case, the different performance of the different cage guidance methods should be noted.

 

The difference between the three cages is mainly manifested in the fact that the performance difference of the bearings of the three cage guidance modes is mainly manifested in the difference in the speed performance under different lubrication conditions.

 

All three cage types can be used for oil and grease lubrication.