Piezoelectric Charge Amplifier In-Situ Calibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for calibrating piezoelectric measuring chains, especially those installed in process-monitoring machines, are complex and require external loading devices or reference loads, making on-site calibration difficult and impractical for dynamic force measurement processes.
Innovation Solution
A method that integrates an arithmetic circuit within the measuring circuit allows for automatic calibration without external loading devices, using a program-controlled electronic computing circuit to adjust the charge amplifier's gain, enabling calibration during normal operating conditions and dynamic processes up to 40 kHz, with only a known reference object and zero point required.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If external loading devices or reference loads are used for calibration, then calibration accuracy can be achieved, but device complexity and ease of operation deteriorate due to required disassembly and external equipment
Solution Approach 1:
The patent combines the calibration function with the existing measuring circuit by integrating an arithmetic circuit that processes signals from both the piezoelectric sensor and a reference sensor. This merging eliminates the need for separate external loading devices and reference loads, reducing device complexity while maintaining calibration accuracy through internal signal comparison and processing.
Solution Approach 2:
The measuring circuit performs calibration autonomously using its own internal resources - the arithmetic circuit processes signals from the piezoelectric sensor and reference sensor simultaneously, automatically calculating calibration factors without requiring external calibration equipment. This self-service approach simplifies the calibration process while maintaining measurement precision.
2Measurement precision
If external loading devices are used for calibration, then calibration can be performed, but ease of operation worsens due to required disassembly and external equipment setup
Solution Approach 1:
The calibration functionality is merged into the existing measuring circuit through the arithmetic circuit, which processes signals from both sensors internally. This integration allows calibration to be performed in-situ without disassembly or external equipment, dramatically improving ease of operation while maintaining calibration capability.
Solution Approach 2:
The system performs calibration autonomously using its own internal signal processing capabilities. The arithmetic circuit automatically compares signals from the piezoelectric sensor and reference sensor, calculating calibration factors without external intervention or equipment, enabling simple on-site calibration operations.
3Device complexity
If the charge amplifier gain is fixed, then device complexity is reduced, but adaptability worsens due to inability to adjust to different measuring ranges
Solution Approach 1:
The patent introduces dynamic adjustability to the charge amplifier gain through the arithmetic circuit, which can modify the amplifier's sensitivity factor based on calibration results. This allows the system to adapt to different measuring ranges and applications while maintaining a relatively simple fixed amplifier circuit design, balancing complexity and adaptability.
Solution Approach 2:
The system changes the operational parameters of the charge amplifier by adjusting its sensitivity factor through the arithmetic circuit. This parameter modification allows the amplifier to adapt to different measuring ranges and calibration requirements without requiring multiple fixed-gain amplifier circuits, maintaining simplicity while improving versatility.
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 precise, high-accuracy calibration of piezoelectric measuring chains in situ, allowing for real-time monitoring and control of manufacturing processes without disassembly, with the ability to detect overloads and maintain linear operation, and includes a TEDS memory circuit for storing transducer parameters for simplified calibration.
Implementation Method 1
a piezoelectric force transducer (1), which generates an electrical charge (Q) when loaded with a force (F), which is proportional to the magnitude of the force (F)
Data Source
Figure 1~3
AI summary
The method involves attaching a charge amplifier (3) with a piezoelectric force transducer. The amplifier is automatically calibrated in a firmly inserted operating mode of the transducer by a computing circuit such that a reference value for maximum force load is detected and stored based on a switching signal or during a reference process flow, by the circuit, so that amplification of the amplifier is controlled by the computing circuit. The amplification is controlled, so that maximum output voltage of the amplifier is associated to maximum force load. An independent claim is also included for a device for calibrating a charge amplifier of a piezoelectric measuring chain.