Bearing-Supported Shaft Assembly With Washer-Stabilized Outer Race
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Aircraft engine shaft assemblies face challenges in maintaining suitable support across varying power outputs due to axial loads from compressors, which can change in magnitude and direction, potentially affecting the spatial relationship and lubrication of bearing components.
Innovation Solution
The shaft assembly includes a bearing assembly with an inner and outer race, a seal located radially outward of the shaft, a housing with a housing wall between the bearing assembly and the seal, and a washer extending axially between the bearing assembly and the seal, which helps in maintaining the outer race's position and ensuring proper lubrication across varying loads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the bearing assembly is supported directly by the shaft without additional components, then the structure is simple, but the bearing assembly cannot maintain consistent spatial relationship and lubrication under varying axial loads
Solution Approach 1:
A washer is introduced as an intermediary component between the bearing assembly and the seal. The washer includes a bearing support portion that interfaces with the bearing assembly and a seal support portion that interfaces with the seal, mediating the interaction between these components and enabling consistent spatial relationships under varying loads
Solution Approach 2:
The washer is designed with flexible or resilient characteristics that allow it to dynamically adapt its position and configuration in response to varying axial loads. This dynamic behavior enables the washer to maintain proper spacing and alignment between the bearing assembly and seal regardless of load direction or magnitude changes
2Adaptability or versatility
If the bearing assembly is allowed to move axially to accommodate varying loads, then the adaptability is improved, but the spatial relationship and lubrication consistency deteriorate
Solution Approach 1:
The washer acts as a mediator that decouples the bearing assembly from direct interaction with the seal and housing. This intermediary structure allows the bearing assembly to accommodate load variations while the washer maintains consistent spatial relationships through its own flexible design
Solution Approach 2:
The support structure is segmented into distinct functional portions: the bearing support portion that interfaces with the bearing assembly, the seal support portion that interfaces with the seal, and intermediate features. This segmentation allows each portion to independently accommodate or resist movement as needed
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A shaft assembly for an aircraft powerplant (1), comprising: a shaft (20) extending along an axis (A) from a first shaft end (20A) to a second shaft end (20B); a bearing assembly (30) extending about the axis and supporting the first shaft end (20A) of the shaft (20), the bearing assembly (30) including an inner race (32) secured to the shaft (20) and an outer race (38) radially outward of the inner race (32) relative to the axis (A); a seal (50) extending about the axis (A) and located radially outward of the shaft (20), the seal (50) disposed axially between the bearing assembly (30) and the second shaft end (20B); a housing (40) having a housing wall located between the bearing assembly (30) and the seal (50); and a washer (60) extending about the axis (A) and located axially between the bearing assembly (30) and the seal (50), the washer (60) extending axially from the outer race (38) to the housing wall.