What Is a Bearing Holder?
A bearing holder is a device used in various machines to support bearings in the correct position to receive the load and rotation of a rotating shaft. It is attached to the machine’s body and holds the bearings by fitting them. The design of a bearing holder must match the load that the bearing is subjected to, and it should have sufficient rigidity based on the bearing size.
Uses of Bearing Holders
Bearing holders are predominantly used in industrial machinery. They must be rigid enough to withstand the load received by the rotating shaft. Considerations such as surface roughness of the bore and corner radii size are important. Bearing holders simplify the design and manufacturing of the housing part that holds the bearing. They are typically mounted as single or double bearing holders for deep groove ball bearings. For angular contact bearings, they can be used with a back-mounted double bearing or with an additional deep groove ball bearing.
Principle of Bearing Holders
Bearing holders serve the following functions:
1. Rigidity
Rigidity is crucial to ensure that the rotating shaft remains in position under load and maintains smooth rotation. Misalignment can cause issues such as gear meshing inaccuracies, noise, or gear damage.
2. Positional Accuracy
Bearing holders are typically screwed to the machine body. Precise alignment of screw holes and bearing holding holes is vital for correct shaft positioning. The housing hole size that holds the bearing is also important to prevent rattling between the bearing and the housing. The housing bore should typically be finished to a tolerance grade of about H7 for a clearance fit.
3. Heat Dissipation
Heat dissipation is especially important when the rotating shaft is under high loads and speeds. Bearing holders play a crucial role in dissipating heat generated by bearings to prevent overheating.
Other Information on Bearing Holders
How to Use Bearing Holders
Correct usage of bearing holders is key to maintaining bearing performance. Methods of mounting bearings, such as flange seizures, retaining rings, and free-running bearings, must be chosen based on the application:
- Flange Holder: Uses a flange to hold and fix the bearing axially. Suitable for applications where axial movement is undesirable.
- Retaining Ring: A groove in the housing holds a retaining ring to prevent the bearing from loosening. Used when axial force is minimal and slight axial movement is acceptable.
- Free-standing: No axial restriction, allowing free movement of the bearing. Typically used to support the free end of a ball screw.