Sheet Metal Bearing Cage With Folded Radial Bars
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bearing cages with sheet metal designs often feature sharp edges and corners that can negatively impact performance and require additional manufacturing steps for smoothing, limiting flexibility and increasing material costs.
Innovation Solution
A bearing cage design where sheet metal elements are folded to create smooth surfaces for contact with rolling elements, eliminating the need for edge smoothing operations and allowing thinner materials to be used, which reduces weight and material costs while enabling more flexible manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If sheet metal elements are used to make bearing cages, then manufacturing cost is reduced and ease of manufacture is improved, but sharp edges and corners are created that harm tribological performance and require additional manufacturing operations
Solution Approach 1:
The sheet metal elements are pre-formed with folded portions that create smooth contact surfaces before assembly. The folding operation is performed in advance during manufacturing, eliminating the need for subsequent edge smoothing operations and ensuring smooth surfaces are already present when the cage is assembled and installed.
Solution Approach 2:
The sharp edges and corners created by cutting sheet metal are converted into beneficial smooth contact surfaces through the folding process. The fold creates a new surface geometry where the previously harmful edge becomes a smooth radially extending surface that improves tribological performance while maintaining the advantages of sheet metal construction.
2Strength
If thicker sheet metal elements are used to ensure sufficient contact width, then strength is improved, but weight increases and material cost increases
Solution Approach 1:
Instead of increasing sheet thickness to achieve sufficient contact width, the invention creates contact surface area by folding the sheet metal radially outward. This transforms a two-dimensional thickness problem into a three-dimensional surface area solution, providing adequate contact area through radial extension rather than axial thickness.
Solution Approach 2:
The contact surface geometry is changed from a flat edgewise contact to a radially extended folded surface. This parameter change in surface orientation and geometry provides sufficient contact width and area while maintaining thin sheet material, thereby reducing weight while preserving strength and contact quality.
3Device complexity
If traditional sheet metal cage designs are used, then manufacturing simplicity is maintained, but additional operations such as chamfering are required to smooth edges
Solution Approach 1:
The folding operation that creates the radially extending contact surfaces is integrated into the primary cage forming process. By combining the structural shaping and surface smoothing operations into a single folding step, the need for separate chamfering or edge smoothing operations is eliminated, improving productivity without increasing device complexity.
Data Source
AI summary
A bearing cage for retaining rolling elements of a rolling element bearing, the bearing cage constructed from a sheet metal element. The cage having at least one cage pocket configured to receive at least one rolling element. The at least one cage pocket is formed by two abutting cage bars that extend axially between a first and a second axially displaced ring element. At least one of the cage bars includes a first portion. The first portion is constructed by folding a part of the sheet metal element such that the first portion extends in a radial direction of the cage and such that an axially extending fold is provided on the cage bar. A rolling element bearing and a method of producing the bearing cage is also provided.