Half Thrust Bearing Resin Coating for Seizure Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional half thrust bearings with uniform resin coating layers fail to provide adequate seizure resistance in high-performance engines due to insufficient oil film formation, leading to potential seizure issues under severe operating conditions.
Innovation Solution
A semi-annular shaped half thrust bearing with a resin coating layer that has a maximum thickness at the center and reduces towards the circumferential ends, featuring a convex contour and controlled thickness distribution defined by a specific equation, facilitating optimal oil film formation and improved seizure resistance without compromising low friction properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a uniform thickness resin coating layer is used, then the manufacturing process is simple, but the oil film formation is insufficient leading to seizure under high surface pressure
Solution Approach 1:
The resin coating layer is designed with non-uniform thickness distribution, having maximum thickness at the center portion and reduced thickness toward circumferential ends. This local variation in coating quality optimizes oil film formation at different locations, with the thicker center portion providing better lubrication where surface pressure is highest, thereby preventing seizure while maintaining manufacturing feasibility.
2Reliability
If the resin coating layer thickness is increased to improve oil film formation, then seizure resistance improves, but friction properties may deteriorate
Solution Approach 1:
The coating thickness is optimized locally rather than uniformly increased. The center portion has maximum thickness for optimal oil film formation and seizure prevention, while the circumferential ends have reduced thickness to maintain low friction properties. This spatially differentiated approach resolves the contradiction between seizure resistance and friction reduction.
Solution Approach 2:
The thickness parameter of the resin coating layer is varied continuously across the surface, with mathematical relationships defining the thickness distribution. This parameter optimization ensures that the coating provides sufficient oil film formation at the center while maintaining appropriate friction characteristics at the edges, achieving both seizure resistance and low friction.
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
The controlled resin coating layer thickness distribution enhances oil film formation and seizure resistance, preventing wear and maintaining low friction properties, even under high surface pressure conditions.
Implementation Method 1
a fluid lubrication film of lubrication oil or the like is formed between a surface of a counter member (e.g., shaft member) and a sliding surface of a sliding member, thereby preventing direct contact between the surface of the counter member and the sliding surface of the sliding member
Implementation Method 2
the resin coating layer has a thickness that is maximum at a center portion of the half thrust bearing in a circumferential direction and is reduced toward circumferential ends of the half thrust bearing
Data Source
Figure 1
Figure 2~3
Figure 4~6
AI summary
This half thrust bearing having a half-ring shape has: a sliding surface for receiving force in the axial direction; a back surface opposed to the sliding surface; and a resin covering layer on the sliding surface. The half thrust bearing is characterized in that the thickness of the resin covering layer is greatest at the circumferential central part of the half thrust bearing, and becomes lesser toward both circumferential ends of the half thrust bearing. The present invention also pertains to a thrust bearing, a bearing device, and an internal combustion engine.