Two types of bearing fixation for gear reducer gearbox

There are two types of bearing fixing forms for the gear box of the gear reducer:

One is to rely on the box cover to press the bearing bush. When machining the bearing hole of the gearbox, the box cover and the box seat need to be assembled together to bore the hole. However, it is cumbersome to carry out the measurement of the bore hole in this way, and because the case cover will bear the load produced by the gear, it must be firm at the fixed bearing bush position, requiring a thicker case wall, while other parts of the case cover only play the role of a casing. Such a design will inevitably make the shape of the whole box cover complicated, and the thickness is uneven, which brings inconvenience to the production of the box cover.

The other is to use the bearing cover to fix the bearing bush separately, use the thinner thickness of the box cover as the sealing shell, and at the same time adopt a flexible bottom structure for the bearing base, and fix the bearing base and the bearing cover together, and then fix it on the box base. Use adjusting shims to adjust the center position of the bearing bush. In this way, the center of the gear can be adjusted arbitrarily as required, thus reducing the strict requirements on the parallelism and inclination of the bore hole. At the same time, after the operation, the deviation of the axis line coordinates due to the deformation of the box can be readjusted more conveniently. This structure Has been adopted by the gearbox with multiple bearings.

Let’s take a closer look at the pros and cons of these two mounting methods and how they affect gear reducer performance and production.

Box Cover-Pressed Bearing Fixing:

This method relies on the box cover to press the bearing bush into place. While it may seem straightforward, it comes with certain drawbacks:

1. Complexity of Machining: When machining the bearing hole of the gearbox, the box cover and the box seat need to be assembled together for the bore hole to be machined. This process can be cumbersome and time-consuming, requiring precise alignment.

2. Structural Integrity: Since the case cover bears the load generated by the gear, it must be firmly fixed at the bearing bush position. This necessitates a thicker case wall in that area, adding to the overall weight and size of the gearbox.

3. Complicated Shape: The design often leads to a complex shape for the box cover, and the thickness may vary across the cover's surface. This complexity can pose challenges during production, especially in terms of machining and quality control.

Bearing Cover Fixing with Flexible Bottom Structure:

This alternative approach seeks to address the limitations of the box cover-pressed bearing fixing method. It employs a separate bearing cover to fix the bearing bush and offers several advantages:

1. Simplified Machining: By fixing the bearing bush separately using the bearing cover, the machining process becomes more straightforward. The need for precise alignment of the box cover and box seat during machining is eliminated.

2. Reduced Weight: The use of a thinner box cover as the sealing shell reduces the overall weight and size of the gearbox, making it more compact and efficient.

3. Flexibility in Center Positioning: The adoption of a flexible bottom structure for the bearing base allows for the easy adjustment of the center position of the bearing bush. This adjustability is essential for ensuring the precise alignment of gears within the gearbox.

4. Tolerance to Deformation: In real-world operation, the gearbox may experience some deformation. With this method, it's easier to readjust the axis line coordinates to compensate for any deviations caused by deformation.

5. Versatility: This bearing fixing method is particularly beneficial for gearboxes with multiple bearings, where flexibility and adjustability are crucial.