Collocated Driver and Pick-off Sensor for Vibrating Fluid Meter
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vibrating fluid meters face challenges in accurately measuring flow characteristics due to changes in zero-flow offset caused by environmental and piping system changes, leading to errors in flow measurements, and previous solutions like combined driver and pick-off sensors are complex and prone to errors.
Innovation Solution
A combined driver and pick-off sensor component is developed, comprising a magnet portion and a coil portion with a driver wire and pick-off wire wound around a coil bobbin, ensuring collocation and reducing the number of components, thereby simplifying measurements and eliminating the need for resistive compensation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If separate driver and pick-off sensor components are used, then the measurement function is complete, but the device complexity increases and collocation accuracy deteriorates
Solution Approach 1:
The patent combines the driver coil and pick-off coil into a single integrated sensor component assembly. The driver coil is wound around a first section of the flow tube while the pick-off coil is wound around a second section, with both coils sharing a common magnet assembly. This merging eliminates the need for separate driver and sensor components, ensuring precise collocation at the same axial position and reducing overall device complexity.
Solution Approach 2:
The integrated sensor component performs multiple functions simultaneously: the driver coil generates electromagnetic force to vibrate the flow tube, the pick-off coil detects the vibration signal, and the shared magnet assembly provides the magnetic field for both functions. This multi-functionality reduces the number of separate components needed while maintaining measurement precision.
2Device complexity
If combined driver and pick-off sensors are used, then the number of components is reduced, but the back-EMF calculation complexity increases
Solution Approach 1:
The patent extracts and separately measures the back-EMF voltage generated by the driver coil during normal operation. By using the integrated sensor component, the back-EMF can be directly measured from the pick-off coil output without requiring complex separation calculations, as the collocated arrangement allows direct differentiation of the signal components.
Solution Approach 2:
The system uses the back-EMF signal generated by the driver coil as feedback to determine the actual vibration frequency and amplitude. This feedback information is used to dynamically adjust the drive signal and compensate for variations in system parameters, simplifying the overall measurement process while maintaining accuracy.
3Strength
If traditional sensor assemblies are used, then the structural integrity is maintained, but the material costs and assembly complexity increase
Solution Approach 1:
The patent merges the driver and pick-off sensor assemblies into a single integrated unit that is installed as one component on the flow tube. This reduces the number of installation steps, minimizes alignment requirements, and simplifies manufacturing while maintaining the structural integrity of the flow tube through the distributed winding arrangement.
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 provides accurate and simplified flow measurements by ensuring collocation of driver and pick-off coils, reducing errors and the complexity of back-EMF calculation, and minimizing the impact of temperature variations, resulting in improved measurement accuracy and reduced material costs.
Implementation Method 1
a driver coil and an opposing pick-off coil, each having substantially the same number of turns and substantially the same diameter. The driver coil and the pick-off coil are substantially coplanar and are separated by a distance equal to the thickness of the flow conduit wall.
Implementation Method 2
the pick-off sensors can use the motion provided by the driver to induce a voltage
Implementation Method 3
As material begins to flow through the flow meter, Coriolis forces cause each point along the conduit(s) to have a different phase
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A combined driver and pick-off sensor component (200, 300) for a vibrating meter is provided. The combined driver and pick-off sensor component (200, 300) includes a magnet portion (104B) with at least a first magnet (211). The combined driver and pick-off sensor component (200, 300) further includes a coil portion (204A, 304A) receiving at least a portion of the first magnet (211). The coil portion (204A, 304A) includes a coil bobbin (220), a driver wire (221) wound around the coil bobbin (220), and a pick-off wire (222) wound around the coil bobbin (220).