Eddy Current Sensor Coil Segmentation for Extended Range
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional eddy current path measurement sensors have limited range and are restricted to detecting distances within 5 mm to 10 mm, and they require continuous sensing, which limits their applications and is prone to external influences, making them unsuitable for harsh industrial environments.
Innovation Solution
A path measurement method using a sensor coil with multiple planar windings, allowing for adjustable inductance and operating frequency, enabling contactless detection of metal objects over a wider range, including distances up to 25 mm to 40 mm, and capable of detecting position, displacement, and vibration without a housing, using standard electronics and without ferromagnetic coils.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional eddy current sensors are used for path measurement, then measurement precision is maintained within a limited range, but the measurement range is restricted to distances within 5 mm to 10 mm
Solution Approach 1:
The sensor coil is divided into multiple individual windings that can be independently connected in series or parallel configurations. This segmentation allows adjustment of the coil's inductance and measurement range while maintaining measurement precision, enabling detection at distances up to 25-40 mm
Solution Approach 2:
The sensor system dynamically adapts its measurement characteristics by switching between different winding configurations (series/parallel connections) and adjusting operating frequency. This dynamic adjustment enables the sensor to maintain optimal measurement precision across extended distance ranges from 5 mm to 40 mm
2Reliability
If continuous sensing is used for path measurement, then measurement reliability is improved, but susceptibility to external influences increases and application versatility is limited
Solution Approach 1:
The sensor uses periodic pulsed measurement instead of continuous sensing. The coil is excited with periodic pulses and the eddy current response is measured during intervals between pulses. This periodic action reduces susceptibility to external electromagnetic influences while maintaining measurement reliability and enables application in harsh industrial environments
3Ease of manufacture
If standard electronics and non-ferromagnetic coils are used, then production costs are reduced and manufacturing ease is improved, but measurement precision in harsh environments may be compromised
Solution Approach 1:
The system compensates for using standard non-ferromagnetic coil materials by dynamically adjusting measurement parameters including operating frequency and pulse duration. These parameter changes optimize the eddy current effect for each specific application, maintaining measurement precision while enabling use of cost-effective standard electronics and materials
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
The solution extends the measurement range, enhances robustness, and allows for reliable detection in harsh conditions, reducing production costs and environmental interference, while maintaining precision and accuracy.
Implementation Method 1
The sensor consists of at least one sensor coil 3, one electronic unit and one housing 16. An oscillator 11 in the electronic unit excites an oscillation... the sensor coil 3 generates a magnetic field
Implementation Method 2
The invention relates to a path measurement method for a sensor which cooperates and/or interacts with a measuring object and/or transducer element and which is based on the so-called eddy current principle
Data Source
AI summary
A method of path measurement uses eddy current principles and a sensor which interacts with a measuring object. The sensor has an electrical connector and a sensor coil. In accordance with the method, an operating voltage is applied to the sensor such that a magnetic field is built up by an oscillator in cooperation with the sensor coil. A measuring object may be moved in the vicinity of the sensor coil through an opening in the sensor coil to produce field strength changes adjacent to the coil and the oscillator. The field strength changes are detected by an evaluation circuit and transmitted to a microcontroller. The microcontroller processes the signals of the evaluation circuit and provides the evaluation circuit with said signals via an output and protection circuit. The sensor coil consists of a plurality of windings constructed in a planar manner.