Ultrasonic Flow Sensor Transit Time Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ultrasonic flow sensors face accuracy and stability issues due to electronic noise and fluid property variations, affecting the measurement of ultrasonic wave transit times.
Innovation Solution
An electronic device comprising a synchronization signal generator, reference pulse generator, sine wave generator, analog signal amplifier, comparator, latch circuits, digital adder, A/D converter, master counter, edge counters, and an arithmetic circuit that measures transit times using both rising and falling edges of the ultrasonic signal, averaging measurements to reduce dependency on threshold levels and signal amplitude variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional threshold-based transit time measurement is used, then the measurement process is simple, but the measurement precision deteriorates due to electronic noise and signal amplitude variations
Solution Approach 1:
The patent divides the ultrasonic signal measurement into multiple discrete sampling points (first measuring point, second measuring point, etc.) along the signal waveform. By measuring transit times at multiple segmented points and averaging them, the system achieves higher precision without requiring complex single-point measurement techniques
Solution Approach 2:
The patent implements a feedback mechanism where the measured transit times from multiple measuring points are fed back through an averaging process to produce a corrected final transit time value. This feedback loop compensates for errors introduced by threshold drift and signal amplitude variations, improving measurement precision
2Reliability
If single measuring point transit time measurement is used, then the measurement process is fast, but the reliability deteriorates due to dependency on threshold level and signal amplitude
Solution Approach 1:
The patent segments the ultrasonic signal measurement into multiple discrete sampling points (first measuring point, second measuring point, third measuring point, etc.) along the waveform. By distributing measurements across multiple segments and averaging the results, the system achieves higher reliability that compensates for the increased measurement time
Solution Approach 2:
The patent employs periodic sampling of the ultrasonic signal at multiple predetermined measuring points along the waveform. This periodic measurement approach at different points allows the system to maintain reliability by capturing consistent transit time data across multiple cycles, reducing the impact of transient noise or amplitude variations
3Measurement precision
If threshold-based measurement method is used, then the device complexity is low, but the measurement precision deteriorates due to threshold drift and electronic noise
Solution Approach 1:
The patent divides the measurement process into multiple independent measuring points along the ultrasonic signal waveform. By segmenting the measurement into multiple points and averaging the results, the system achieves precision that is independent of threshold drift and electronic noise, while maintaining adaptability to different fluid properties
Solution Approach 2:
The patent changes the measurement parameter from a single threshold-based detection point to multiple measuring points distributed along the signal waveform. This parameter change makes the measurement system adaptable to variations in fluid properties, electronic noise levels, and signal amplitude, as the averaging process compensates for these variations
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 significantly improves the accuracy and robustness of ultrasonic flow sensor velocity measurements by minimizing errors caused by threshold drift and signal amplitude fluctuations.
Implementation Method 1
an ultrasonic flow sensor measures the average velocity of liquid or gaseous media by means of ultrasonic transducers based on the principle that the transit time of an ultrasonic wave from the transmitter of a transducer to the corresponding receiver is determined by the fluid velocity and the ultrasonic wave propagating direction
Implementation Method 2
measures the average velocity of liquid or gaseous media by means of ultrasonic transducers
Data Source
AI summary
A device for measurement of ultrasonic wave transit times of an ultrasonic flow sensor consists of: 1) a synchronization signal generator, 2) a reference pulse generator, 3) a sine wave generator, 4) an analog signal amplifier, 5) a comparator, 6) a plurality of latch circuits, 7) a digital adder, 8) an integrator, 9) an A/D converter. 10) a master counter, 11) a plurality of edge counters, and 12) an arithmetic circuit. The device measures the ultrasonic wave transit times using a method of averaging the ultrasonic wave arriving limes at different measuring points (triggering point). This method has less dependency on triggering threshold level and the ultrasonic signal amplitude, and thus has less dependency on threshold drift, threshold stability, system gain fluctuation, electronic noise and signal amplitude variations. As a result, the method can greatly improve the velocity measurement accuracy and system robustness of an ultrasonic flow sensor.