Rolling Bearing Recessed Grease Structure for Low Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rolling bearings face challenges in balancing reduced rotational resistance with the need to ensure durability, as reducing grease amounts can lead to insufficient base oil supply and shortened service life.
Innovation Solution
A rolling bearing design featuring an inner and outer ring with a recessed portion on the raceway surface side, where the grease is in contact with the recessed portion and has an unworked penetration greater than 178 and less than 287, restricting grease displacement and ensuring adequate base oil supply.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the amount of grease is reduced to minimize contact with rolling bodies and cages, then rotational resistance is reduced, but base oil supply becomes insufficient and service life is shortened
Solution Approach 1:
The grease is segmented into two functional zones: a first grease portion positioned away from rolling bodies and cages to minimize rotational resistance, and a second grease portion placed in a recessed portion of the raceway surface to ensure continuous base oil supply to rolling bodies. This spatial segmentation resolves the contradiction by allowing each grease portion to serve its specific function optimally.
Solution Approach 2:
Different regions of the bearing have different grease requirements. The invention applies grease with different characteristics to different locations: the first grease portion (away from rolling bodies) uses grease with lower viscosity to reduce rotational resistance, while the second grease portion (in the recessed portion) uses grease with higher viscosity to ensure reliable base oil supply. This local differentiation resolves the contradiction between reducing rotational resistance and ensuring service life.
2Quantity of substance
If grease is placed on a placement surface with an inclined portion leading to the raceway surface, then grease is contained, but base oil flow path becomes long and supply ability decreases over time
Solution Approach 1:
The invention extracts the grease containment function from the raceway surface structure and relocates it to a dedicated recessed portion. By providing a separate recessed portion specifically for grease storage, the design eliminates the need for long inclined flow paths while ensuring grease retention. The second grease portion is directly accessible to rolling bodies through the recessed portion, ensuring continuous base oil supply without relying on long flow paths.
3Reliability
If grease unworked penetration is increased to improve base oil supply, then grease becomes too soft and cannot be properly contained, but if penetration is decreased for containment, base oil supply ability is reduced
Solution Approach 1:
The invention applies grease with different penetration values to different locations: the first grease portion uses grease with lower unworked penetration (better containment) while the second grease portion uses grease with higher unworked penetration (better base oil supply). This local differentiation of grease properties resolves the contradiction between containment and supply ability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design effectively reduces rotational resistance by minimizing grease contact with rolling bodies and cages, while maintaining durability through continuous base oil supply and controlled grease distribution.
Implementation Method 1
unworked penetration of the grease is greater than 178 and less than 287, base oil oozing from the grease has to flow along the inclined portion and then goes over the ridge portion until the base oil reaches the raceway surface
Implementation Method 2
the recessed portion includes a placement surface on which grease is placed and an inclined portion formed between the placement surface and the ridge portion and approaching an outer circumferential surface of the outer ring toward an outer side in the axial direction
Data Source
AI summary
To provide a rolling bearing capable of ensuring durability and reducing rotational resistance. The rolling bearing includes an inner ring and an outer ring disposed coaxially with each other; a rolling body disposed between the inner ring and the outer ring; a sealing member mounted on the outer ring and covering a space between the inner ring and the outer ring from an outer side in an axial direction; and grease disposed between the rolling body and the sealing member. The outer ring has an inner circumferential surface facing the inner ring. The inner circumferential surface is formed with an outer ring raceway surface that supports the rolling body in a rollable manner, and a recessed portion that is provided at a location extending in the axial direction from an end edge of the outer ring raceway surface in the axial direction and is recessed in a radial direction. The grease is in contact with the recessed portion. Unworked penetration of the grease is greater than 178 and less than 287.