Rolling Device Lubrication Diagnosis with Wiring Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for diagnosing the lubrication state in rolling devices, such as bearings, suffer from decreased measurement accuracy when the rotational speed is low, leading to inaccurate calculations of lubricating film thickness and metal contact ratio.
Innovation Solution
A method involving the application of an AC voltage to an electric circuit comprising a rolling element and its peripheral member, followed by measuring impedance and phase angle, and correcting these values using a correction formula based on Kirchhoff's law to account for wiring components, allowing for accurate calculation of lubricating film thickness and metal contact ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If impedance and phase angle are measured using conventional methods, then the lubrication state can be diagnosed, but measurement accuracy decreases at low rotational speeds
Solution Approach 1:
The invention extracts and separates the wiring component parameters (resistance and reactance) from the total measured impedance and phase angle. By measuring the wiring parameters independently and subtracting them from the total measurements, the method isolates the rolling device parameters, thereby eliminating the source of measurement error that becomes significant at low rotational speeds
Solution Approach 2:
The invention changes the measurement approach by introducing a correction process that transforms the raw impedance and phase angle measurements into corrected values. This parameter transformation using Kirchhoff's law-based correction formulas adjusts the measurement data to compensate for wiring effects, maintaining accuracy across different rotational speed ranges
2Manufacturing precision
If wiring components are not considered in measurement, then the diagnostic process is simpler, but calculation accuracy of lubricating film thickness and metal contact ratio deteriorates
Solution Approach 1:
The invention segments the measurement system into distinct components: wiring components and rolling device components. By separating the measurement into these segments and analyzing each independently, the method achieves higher calculation accuracy for lubricating film thickness and metal contact ratio while maintaining a manageable measurement process structure
Solution Approach 2:
The invention performs preliminary measurement of wiring parameters (resistance and reactance) before conducting the main rolling device measurement. This preliminary action allows the wiring characteristics to be characterized in advance, enabling their effects to be removed from the subsequent rolling device measurements without adding significant complexity to the overall process
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
Enhances the accuracy of lubrication state diagnosis in rolling devices, particularly at low rotational speeds, preventing uncalculated film thickness and unreasonable metal contact ratio values.
Implementation Method 1
measuring an impedance and a phase angle of the electric circuit when the AC voltage is applied
Implementation Method 2
correcting the measured impedance and the measured phase angle using a correction formula based on a solution of Kirchhoff s law defined corresponding to a resistance and a reactance by a wiring component
Data Source
Figure 1
Figure 2
Figure 3
AI summary
This method for diagnosing a rolling device comprising rolling elements and peripheral members of the rolling elements includes: applying an alternating-current voltage to an electric circuit comprising the rolling elements and the peripheral members; measuring an impedance and a phase angle when the alternating-current voltage is applied; correcting the measured impedance and the measured phase angle using a correction formula based on a solution of Kirchhoff's laws, defined in accordance with a resistance and a reactance resulting from a wiring component in the electric circuit; and calculating a lubricating film thickness and a metal contact ratio on the basis of the corrected impedance and the corrected phase angle.