Bearing Defect Estimation via Displacement Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing acceleration-based vibration condition monitoring methods for bearings face challenges in scalability, reproducibility, and accurately quantifying surface defect severity, particularly in real-world conditions where disturbances and deteriorated vibration transfer paths obscure defect signatures.
Innovation Solution
A method and device that measure weighted relative displacement values between a bearing's housing and stationary ring using displacement sensors, determining cyclostationary contact forces through linear equations and basis functions, and comparing these forces to a detection threshold to estimate surface defect size, which improves defect severity evaluation and prediction of bearing failure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If acceleration-based vibration monitoring is used, then defect detection capability is provided, but measurement precision deteriorates due to disturbances and deteriorated vibration transfer paths
Solution Approach 1:
The patent introduces displacement sensors as an intermediary measurement device that directly measures the relative displacement between the bearing inner ring and housing, bypassing the deteriorated vibration transfer path. This mediator (displacement sensor) captures the actual defect-induced displacement without being affected by the harmful vibration transfer path issues that plague acceleration-based methods.
Solution Approach 2:
The patent replaces the acceleration-based vibration measurement system with a direct displacement measurement system. By substituting acceleration sensors with displacement sensors and measuring actual relative displacement rather than vibration acceleration, the system eliminates the harmful effects of vibration transfer path deterioration while maintaining defect detection capability.
2Reliability
If vibration signals are processed to estimate defect size, then defect severity evaluation is attempted, but reliability deteriorates due to poor scalability and reproducibility
Solution Approach 1:
The patent creates a universal measurement approach by directly measuring relative displacement between the inner ring and housing, which is applicable across different bearing types, sizes, and machine configurations. This universal displacement measurement method replaces the non-scalable vibration-based approaches, enabling reliable defect severity evaluation that can be reproduced across different machines and bearing designs.
Solution Approach 2:
The patent fundamentally changes the measurement parameter from vibration acceleration to direct relative displacement. This parameter change transforms the measurement into something that is inherently scalable and reproducible, as displacement is a direct geometric quantity that does not depend on the complex vibration transfer characteristics that vary between machines and bearing designs.
3Measurement precision
If weighted relative displacement values are measured using displacement sensors, then measurement precision improves, but device complexity increases
Solution Approach 1:
The patent merges the measurement of relative displacement between the inner ring and housing into a single direct measurement using displacement sensors mounted on the housing. By combining the reference frame (housing) and the measured object (inner ring) into one direct measurement system, the complexity is reduced compared to using multiple separate sensors or indirect vibration measurements that require complex signal processing.
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 approach enhances the accuracy of bearing condition monitoring by providing a robust and scalable method to detect and quantify surface defects, even in complex machine environments, and accurately predicts the risk of bearing failure.
Implementation Method 1
measuring, with the displacement sensor relative weighted displacement values between the housing and the stationary ring within the area of the recess
Data Source
AI summary
A device (10) for estimating the size of a surface defect of a bearing (9). The device (8) includes a conditioning means (15), a first determining means (16), a second determining means (17), a solving means (18), a comparing means (19), a detecting means (20), and a third determining means (21).