Understanding of "guidance" at home and abroad

At present, the cage design in the domestic bearing industry has three guidance methods: outer guidance, inner guidance and rolling element guidance. There is no clear definition of these three guidance methods in the current standards and bearing professional teaching materials. Based on years of industry experience, "guidance" in the traditional sense can be understood as "who" drives the cage.

Taking the angular contact ball bearing with phenolic laminated cloth tube cage as an example, the three guiding methods for the cage can be understood as:

1. Rolling element guidance. During the operation of the bearing, only the pocket and the steel ball have collision and friction, and the cage will not contact with other parts of the bearing (inner/outer ring, seal ring).

2. External guidance. During the operation of the bearing, in addition to the collision of pockets and rolling elements, the small inner diameter of the bearing outer ring may contact the outer diameter of the cage.

3. Inside guide. During the operation of the bearing, in addition to the collision between the pockets and the rolling elements, the outer diameter of the bearing inner ring may contact the inner diameter of the cage.

We have also seen the descriptions of "rolling element guidance" and "outside guidance" in the catalogs of FAG and NSK companies. Companies such as GMN and NSK do have the idea of "outside cage guidance". For the so-called "outside cage guidance" products on the catalogs of some foreign companies, most of the results of physical measurement still conform to our understanding of "rolling element guidance". Except for the full complement ball bearing and full complement roller bearings without cage, in order to prevent the rolling elements from colliding with each other during operation, the bearing needs a cage to isolate the rolling elements. It means that the main function of the cage is to isolate the rolling elements.

According to the different speed requirements (super high speed, medium speed, low speed) of the bearing operating conditions, the Center diameter of cage can be adjusted in the design of the angular contact ball bearing to realize the external design, center design and internal design under the guidance of the rolling elements. High-speed and ultra-high-speed bearings use the external design, medium-speed bearings use the center design, and low-speed bearings use the internal design.