As an important part of the bearing, the cage plays a role of guiding and separating the rolling body. The guiding role of the cage refers to the correction of the running of the rolling body. This modification is achieved by the collision of the cage with the surrounding parts.

There are three ways to guide the general bearing cage: roller guide, inner ring guide and outer ring guide.

Scroll guide:

General design of the standard structure of guide roller, such as short cylindrical roller bearing, the guide roller and cage and out of touch with both internal and external circle surface of the guard, cage can be common, but under the high speed roller speed increased, the rotation is not stable, so the guide roller is suitable for medium and medium load, such as gear box bearing, etc.

The bearing retainer guided by the rolling body is located in the middle of the rolling body. Neither the cage nor the bearing inner or outer rings are in contact with each other, and the collision between the cage and the roller corrects the roller motion, while separating the rollers at a certain distance.

Outside guide:

The outer ring is generally static, and the outer ring guide facilitates the lubricating oil to enter the guide surface and raceway. The high speed gearbox is lubricated with oil mist and guided by a rotating inner ring will squeeze out the oil. The bearing retainer guided by the outer ring is located on the side of the rolling body near the outer ring. During bearing operation, the bearing retainer may collide with the outer ring of the bearing to correct the position of the retainer.

The outer ring guide is generally used in the case of high speed and stable load. Taking the cylindrical roller bearing as an example, it only bears a fixed value of axial load. During rotation, the rotation speed of each rolling body does not change much, and the rotation of the cage is not unbalanced.

Inner guide:

The inner ring is generally a rotating ring, and provides a rolling body to drag torque when rotating, if the bearing load is unstable, or light load, there will be sliding.

When the cage is guided internally, an oil film is formed on the guide surface of the cage. As the friction of the oil film gives the cage a drag force in the non-load zone, the additional driving moment of the cage on the rolling body is increased, which can prevent the cage from slipping.

The bearing retainer guided by the inner ring is located near the rolling body to the inner ring. During bearing operation, the retainer may collide with the inner ring of the bearing, thus correcting the retainer position.

The three retainer guide modes may appear in different types of bearings, including performance reasons, as well as the design and manufacture of the bearings themselves. Engineers can choose according to their needs. But sometimes engineers don't have a choice. However, the different performance of the different retainer boot modes should be noted.

The difference of the three retainers is mainly reflected in: the performance difference of the bearings guided by the three retainers is mainly reflected in the performance difference of the rotation speed under different lubrication conditions.

Bearings of all three types of cage can be used for oil and grease lubrication.