Shaft Alignment Device Using Quality-Based Data Filtering

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing shaft alignment measuring devices face challenges in achieving reliable measurements due to measurement errors caused by clutch play, angular acceleration, and non-optimal connections, leading to deviations in light beam impact positions and reduced reliability of curve-fitted data.

Innovation Solution

A method and device that assess the quality of individual measurement data points based on angular velocity, angular acceleration, and deviation from a fitted curve, excluding low-quality data to improve the reliability of shaft displacement determination, and allowing for partial revolution measurements with curve fitting to extrapolate over the remaining angles.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If measurement data is collected during shaft rotation to determine alignment, then alignment information can be obtained, but measurement errors occur due to clutch play, angular acceleration, and non-optimal connections causing deviations in light beam impact positions

Engineering Contradiction:
Improvealignment measurement accuracyVSAvoidmeasurement data reliability
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The system performs preliminary actions by evaluating the quality of measurement data points before final curve fitting. It calculates angular velocity and angular acceleration for each measurement point, identifies suspicious points using quality criteria, and removes them before determining the final alignment parameters. This preliminary filtering ensures that only high-quality data contributes to the alignment measurement, resolving the contradiction between obtaining alignment information and avoiding measurement errors.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system implements feedback by continuously monitoring measurement quality through angular velocity and angular acceleration calculations. It uses this feedback to identify and exclude suspicious measurement points that deviate from expected patterns, thereby improving the reliability of the final alignment determination while maintaining measurement precision.

Inventive Principle:
Principle #23Feedback

2Measurement precision

If complete revolution measurements are performed to ensure accurate curve fitting, then alignment precision improves, but measurement time increases

Engineering Contradiction:
Improvecurve fitting accuracyVSAvoidmeasurement duration
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The system applies partial action by performing quality-based filtering on measurement points during rotation. Instead of requiring complete revolutions for sufficient data, it selectively uses high-quality measurement points that meet predetermined criteria, achieving accurate curve fitting with reduced measurement time and fewer required revolutions.

Inventive Principle:
Principle #16Partial or excessive action

3Measurement precision

If multiple measurement points are collected to improve curve fitting reliability, then data accuracy improves, but the influence of suspicious data points from clutch play and vibrations increases

Engineering Contradiction:
Improvedata accuracyVSAvoidvibration and clutch play interference
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The system extracts and removes suspicious measurement points from the data set before final curve fitting. By calculating angular velocity and angular acceleration for each point and comparing them against quality criteria, it identifies and excludes data points affected by clutch play, vibrations, and non-optimal connections, thereby improving the reliability of the remaining data for alignment determination.

Inventive Principle:
Principle #2Taking out (Extraction)

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 reliability of shaft misalignment determination by filtering out poor-quality data points and achieving accurate alignment measurements even with partial revolution data, thereby increasing the confidence in the determined shaft offset.

Implementation Method 1

At least one of the two measuring units has means for generating at least one light beam

Methodology Applied
Scientific EffectLight beam propagation: Light

Implementation Method 2

at least one of the two measuring units has detection means for acquiring data relating to the impact position of the light beam on at least one detection surface

Methodology Applied
Scientific EffectOptical detection: Photoelectric Effect

Implementation Method 3

at least one of the two measuring units is provided with at least one sensor for detecting the angle of rotation of the shaft

Methodology Applied
Scientific EffectAngular position detection:

Data Source

PatentEP2733459B1Device and method for determining the relative position of two coupled shafts to each other
Publication Date: 2019.07.10 PRUEFTECHNIK DIETER BUSCH GMBH
  • EP2733459B1 patent drawingFigure 1~2
  • EP2733459B1 patent drawingFigure 3A~4
  • EP2733459B1 patent drawingFigure 5~6

AI summary

The device has an analysis unit (30) that determines angle-of-rotation position, angular velocity and angular acceleration of shafts (10,12) in measured positions from the sensor data showing angle of rotation of shafts. Analysis unit analyzes quality of sensor data, based on difference between impingement positions of a light beam bundle (22) on detection area (24,26). Analysis unit analyzes quality rating of sensor data to exclude measured position data and to consider only reduced weighting data for determining the shaft offset, when quality rating lies below threshold value.