Sliding Bearing With Segmented Cavity Zones

Solution Overview

Problem

Journal bearings face challenges in maintaining low friction under full lubricant film conditions and adequate lubrication under poor lubrication conditions, as existing designs compromise between these requirements, leading to premature wear and inefficient operation.

Innovation Solution

The bearing features distinct areas with different types of cavities, one designed for reducing friction and carrying the load under full lubrication, and another for providing lubrication under poor lubrication conditions, separated by boundaries such as relief grooves, ensuring optimal performance in both scenarios.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If very shallow cavities are used, then low friction under full lubricant film conditions is achieved, but insufficient lubricant availability under poor lubrication conditions results

Engineering Contradiction:

ImprovefrictionVSAvoidlubricant availability

Core Design Contradiction:

Loss of energyVSQuantity of substance

Solution Approach 1:

The bearing surface is divided into multiple zones with different cavity characteristics. Some zones have shallow cavities optimized for low friction under full lubrication, while other zones have deeper cavities that store lubricant for poor lubrication conditions. This segmentation allows each zone to fulfill its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the bearing surface are given different local properties through varying cavity depths and distributions. The local quality of each cavity is tailored to its specific functional requirement - shallow cavities in load-bearing areas for friction reduction, deeper cavities in lubricant storage areas for maintaining lubrication during startup or starvation conditions.

Inventive Principle:

Principle #3Local quality

2Quantity of substance

If relatively deep cavities are used, then sufficient lubricant is available under poor lubrication conditions, but pressure build-up under full lubrication conditions increases leading to higher friction

Engineering Contradiction:

Improvelubricant availabilityVSAvoidfriction

Core Design Contradiction:

Quantity of substanceVSLoss of energy

Solution Approach 1:

The bearing surface is divided into multiple zones with different cavity characteristics. Some zones have shallow cavities optimized for low friction under full lubrication, while other zones have deeper cavities that store lubricant for poor lubrication conditions. This segmentation allows each zone to fulfill its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the bearing surface are given different local properties through varying cavity depths and distributions. The local quality of each cavity is tailored to its specific functional requirement - shallow cavities in load-bearing areas for friction reduction, deeper cavities in lubricant storage areas for maintaining lubrication during startup or starvation conditions.

Inventive Principle:

Principle #3Local quality

3Ease of manufacture

If uniform cavity distribution is used, then simplified manufacturing is achieved, but inadequate performance under both full film and poor lubrication conditions results

Engineering Contradiction:

Improvecavity uniformityVSAvoidlubrication performance

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

Different regions of the bearing surface are given different local properties through varying cavity depths and distributions. The local quality of each cavity is tailored to its specific functional requirement - shallow cavities in load-bearing areas for friction reduction, deeper cavities in lubricant storage areas for maintaining lubrication during startup or starvation conditions.

Inventive Principle:

Principle #3Local quality

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 configuration maintains low friction and full lubrication film behavior under adequate lubrication while ensuring sufficient lubrication during poor lubrication conditions, reducing wear and extending the bearing's life by isolating the effects of deep and shallow cavities.

Implementation Method 1

at least one of the bearing surfaces being provided with a first type of cavities which may comprise a lubricating substance, and with a second type of cavities which may comprise a lubricating substance

Methodology Applied

Scientific EffectLubrication: Lubrication

Data Source

PatentUS8231277B2Sliding bearing with different sets of cavities

Publication Date: 2012.07.31 AB SKF SKF PATENT DEPARTMENT

AI summary

A sliding bearing, such as a journal bearing, includes at least two bearing elements, the bearing surfaces of which are slidably supported with respect to each other. At least one of the surfaces is provided with a first type of cavity which may comprise a lubricating substance, the first type of cavity being defined by a specific range of geometric properties. At least one surface is provided with at least a second type of cavity which may comprise a lubricating surface, the second type of cavity being defined by geometric properties which are different from the geometric properties of the first type of cavity.