Rolling Bearing Strain Gauge Layout for Trajectory Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional rolling bearings are unable to detect the trajectory of rolling elements during rotation.

Innovation Solution

A rolling bearing design incorporating a strain gauge with three or more detector elements disposed on the outer or inner ring, arranged to detect strain in the circumferential and axial directions, allowing for the detection of rolling element trajectory through resistance changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional strain gauges with two detector elements are used, then the structure is simple, but the rolling element trajectory cannot be detected

Engineering Contradiction:
Improvetrajectory detection capabilityVSAvoidstrain gauge structure
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent transitions from a one-dimensional arrangement (two detector elements along the axial direction) to a two-dimensional arrangement (three or more detector elements distributed on the outer peripheral surface at different circumferential and axial positions). This dimensional expansion enables the detection of trajectory information that requires spatial distribution in multiple directions, resolving the contradiction between measurement precision and device complexity.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The strain gauge is segmented into multiple detector elements (three or more) positioned at different locations on the outer peripheral surface. Each detector element independently measures strain at its specific position, and the combined data from these segmented elements enables trajectory detection, overcoming the limitation of conventional two-element gauges while maintaining manageable structural complexity.

Inventive Principle:
Principle #1Segmentation

2Measurement precision

If two detector elements are arranged along the axial direction, then the manufacturing is simple, but the trajectory detection is not possible

Engineering Contradiction:
Improvetrajectory detection accuracyVSAvoidstrain gauge arrangement
Core Design Contradiction:
Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent moves from a one-dimensional axial arrangement to a two-dimensional distribution pattern on the outer peripheral surface, incorporating both circumferential and axial position variations. This dimensional change enables trajectory detection capability while the detector elements are arranged following the natural curvature of the outer peripheral surface, which facilitates manufacturing through conventional wrapping or bonding techniques.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Measurement precision

If three or more detector elements are distributed on the outer peripheral surface, then the trajectory can be detected, but the device complexity increases

Engineering Contradiction:
Improvetrajectory detection capabilityVSAvoiddetector element arrangement
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent utilizes the two-dimensional outer peripheral surface of the outer ring as the mounting surface for detector elements. By distributing three or more elements across different circumferential and axial positions on this curved surface, the system achieves trajectory detection capability. The outer peripheral surface provides a natural, pre-formed two-dimensional platform that reduces the complexity of creating the detector arrangement compared to flat or irregular surfaces.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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

Enables accurate detection of rolling element trajectory, predicting bearing lifetime and diagnosing remaining life, with high sensitivity and accuracy using a Cr composite film gauge factor of 10 or more.

Implementation Method 1

a strain gauge disposed on an outer peripheral surface of the outer ring or an inner peripheral surface of the inner ring. The strain gauge includes three or more detector elements that are disposed on the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring

Methodology Applied
Scientific EffectStrain gauge resistance change: Piezoresistive Effect

Data Source

PatentEP4365457B1Rolling bearing
Publication Date: 2025.10.08 MINEBEAMITSUMI INC
  • EP4365457B1 patent drawingFigure 1
  • EP4365457B1 patent drawingFigure 2(a)~2(c)
  • EP4365457B1 patent drawingFigure 3~4

AI summary

This rolling bearing has an outer race having a predetermined axis of rotation; an inner race disposed on the inner circumferential side of the outer race and in a manner concentric to the outer race; a plurality of rolling bodies disposed between the outer race and the inner race; and a strain gauge that detects strain on the outer race or the inner race. The strain gauge has three or more detection elements disposed on the outer circumferential surface of the outer race or on the inner circumferential surface of the inner race. The three or more detection elements include at least two detection elements located at positions different in the direction along the axis of rotation and in the circumferential direction of the outer race or the inner race.