Vibration-Type Measuring Transducer Non-Resonant Diagnostics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional measuring systems for free-flowing media, such as Coriolis mass flow meters, face challenges in detecting signs of wear or aging that reduce measuring accuracy and operational reliability, often requiring interruptions to the measurement process and relying on medium parameters for diagnosis.
Innovation Solution
The system actively excites measuring tubes out of resonance using modified driver signals, allowing for early detection and diagnosis of errors through vibration signals, independent of the medium flowing, with conventional transducers and electronics, enabling continuous operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional measuring systems use resonance-based vibration detection, then measurement accuracy is maintained, but the system cannot detect wear or aging signs and requires interruptions for diagnosis
Solution Approach 1:
The patent applies periodic action by alternating between resonance-based measurement mode and non-resonance-based diagnostic mode. The system periodically switches between these two operational states, allowing it to maintain measurement accuracy during resonance periods while detecting wear signs during non-resonance periods, thus resolving the contradiction between reliability and measurement precision.
Solution Approach 2:
The patent implements preliminary action by performing diagnostic measurements using non-resonance vibrations before wear or aging significantly impacts measurement accuracy. This early detection capability allows the system to identify potential issues while still maintaining reliable operation, preventing future measurement errors.
2Reliability
If the system interrupts the measurement process for diagnosis, then wear and aging can be detected, but productivity decreases
Solution Approach 1:
The patent applies continuity of useful action by enabling diagnostic measurements to be performed during normal operational periods without requiring process interruptions. The system continuously monitors for wear signs using non-resonance vibrations while the process operates, and only interrupts measurements when actual wear is detected, thus maintaining both reliability and productivity.
Solution Approach 2:
By performing preliminary diagnostic checks during normal operation, the system detects wear early before it affects measurement accuracy, eliminating the need for unplanned interruptions and maintaining continuous productivity while ensuring measurement reliability.
3Difficulty of detecting and measuring
If the system uses medium parameters for diagnosis, then detection is possible, but the method is limited by medium flow conditions
Solution Approach 1:
The patent introduces an intermediary approach by using the measuring tube itself as the diagnostic medium. Instead of relying on process medium parameters, the system uses vibrations of the measuring tube structure to detect wear signs. This intermediary method decouples the diagnostic capability from medium flow conditions, allowing detection regardless of whether the process is flowing or stagnant.
Solution Approach 2:
The patent replaces reliance on medium-based diagnostic parameters with a mechanical vibration-based diagnostic system. By substituting medium parameter analysis with direct mechanical vibration measurement of the measuring tube, the system achieves independence from medium flow conditions while maintaining detection capability.
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 for early and reliable detection of errors, maintaining measuring accuracy and operational reliability without interrupting the measurement process, and can be done using existing transducer designs and electronics.
Implementation Method 1
the converter electronics are set up to feed electrical excitation power into the vibration exciter by means of a driver signal which has at least temporarily a signal component of a second type with a signal frequency which deviates from each instantaneous natural frequency of each natural vibration mode of the at least one measuring tube
Implementation Method 2
the at least one measuring tube, excited by at least one vibration exciter, executes at least partially forced vibrations out of resonance
Data Source
Figure 1a~1b
Figure 2a~2b
Figure 3
AI summary
The measuring system comprises a vibration-type transducer (MW) for generating vibration signals corresponding to the medium parameters of a flowing medium, in particular a mass flow rate, a density and/or a viscosity, as well as electrically coupled converter electronics (ME) to the transducer for controlling the transducer and for evaluating vibration signals supplied by the transducer.The measuring transducer (MW) has at least one measuring tube (10; 10') extending between an inlet-side first measuring tube end and an outlet-side second measuring tube end with a useful oscillation length, which is inhabited by a plurality of natural vibration modes, for guiding flowing medium, at least one vibration exciter (41) for converting electrical excitation power into vibrations of the at least one measuring tube and at least one vibration sensor (51; 52) for detecting vibrations of the at least one measuring tube and for generating a vibration signal (ssens1) of the measuring transducer representing vibrations of at least the at least one measuring tube.The converter electronics (ME) provides, during operation, a driver signal (sdrv) for the at least one vibration exciter (41) for the purpose of supplying electrical excitation power to the at least one vibration exciter (41), and thus for causing vibrations of the at least one measuring tube, such that the driver signal (sdrv) has at least temporarily a sinusoidal signal component (sdrv,I) of the first kind with a signal frequency, fdrv,I, which corresponds to an instantaneous natural frequency, f1, of a natural first-order vibration mode of the at least one measuring tube, in which the at least one measuring tube can perform natural oscillations around a rest position.details which natural oscillations in the region of the first and second measuring tube ends each have a node and in the region of the useful oscillation length exactly one antinode, and that the driver signal (sdrv) has at least temporarily a sinusoidal signal component (sdrv,II) of the second kind with a signal frequency, fdrv,II, which deviates from each instantaneous natural frequency of each natural oscillation mode of the at least one measuring tube by more than 1Hz and/or by more than 1% of that natural frequency.