Piezoelectric Resonant Circuit State Detection Without Calibration Electrodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the state of piezoelectric elements in sensor apparatuses, such as temperature and functional state, require additional calibration electrodes, which incur costs and can mechanically influence the vibration behavior of the piezoelectric element.
Innovation Solution
A method involving a resonant circuit with a piezoelectric element and an ohmic resistor, excited by an active component like a Schmitt trigger, captures natural vibrations to determine the element's state without needing a dedicated calibration electrode, using period durations of natural vibrations to infer temperature and functional state.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a calibration electrode is installed to determine the state of the piezoelectric element, then measurement precision is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The existing electrodes (measurement electrode and counter electrode) are made to serve dual purposes: their original function for voltage detection and an additional function for state determination through resonant frequency measurement. This eliminates the need for separate calibration electrodes while maintaining measurement capabilities.
Solution Approach 2:
The electrode system is designed to perform multiple functions: detecting operational voltage and determining structural state through electrical resonance measurements, thereby replacing dedicated calibration electrodes with multi-functional existing electrodes.
2Measurement precision
If a calibration electrode is installed to determine the state of the piezoelectric element, then measurement precision is improved, but manufacturing cost increases
Solution Approach 1:
The existing electrodes (measurement electrode and counter electrode) are made to serve dual purposes: their original function for voltage detection and an additional function for state determination through resonant frequency measurement. This eliminates the need for separate calibration electrodes while maintaining measurement capabilities.
3Measurement precision
If mechanical contact is created for temperature measurement, then measurement precision is improved, but the vibration behavior of the piezoelectric element is influenced
Solution Approach 1:
The patent replaces mechanical/thermal contact measurement methods with electrical resonance frequency measurement. By measuring the electrical resonance of the piezoelectric element itself, the state information is obtained without physical contact that would disturb the vibration behavior.
Solution Approach 2:
The piezoelectric element serves itself for state determination by utilizing its own electrical resonance characteristics. The element's inherent electrical properties are measured to determine its state, eliminating the need for external measurement devices that would require mechanical contact.
4Measurement precision
If additional calibration electrodes are installed, then state determination capability is improved, but the natural vibration behavior of the piezoelectric element is affected
Solution Approach 1:
The piezoelectric element serves itself for state determination by utilizing its own electrical resonance characteristics. The element's inherent electrical properties are measured to determine its state, eliminating the need for external measurement devices that would require mechanical contact.
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 allows precise determination of the piezoelectric element's state without mechanical interference, reducing costs and enhancing accuracy through efficient resource use and high scanning rates.
Implementation Method 1
An electrical voltage is generated by deformation of the piezoelectric element
Implementation Method 2
natural vibrations are induced in the resonant circuit, that the period durations of the natural vibrations of the resonant circuit are captured
Implementation Method 3
The separation of the electrodes of the piezoelectric element is dependent on the expansion of the piezoelectric material, wherein the expansion and thus also the separation of the electrodes depends on temperature
Data Source
AI summary
A method for determining the state of a piezoelectric element, in particular the piezoelectric element of a sensor apparatus, it is provided. The piezoelectric element is a component of a resonant circuit. The resonant circuit is excited to natural vibrations. The period durations of the natural vibrations of the resonant circuit are captured, and conclusions are drawn regarding the state of the piezoelectric element base on the period durations of the natural vibrations. A sensor apparatus with at least one piezoelectric element is provided. The sensor apparatus has at least one resonant circuit and that the piezoelectric element is a component of the resonant circuit. The sensor apparatus includes at least one evaluator for capturing and evaluating the natural vibrations of the resonant circuit. The evaluator includes at least one storage device for storing reference resonance frequencies that have been determined in advance.