Coriolis Flow Meter PCB Support for Driver and Pick-off Components
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Coriolis flow meters face issues with attaching wires to moving flow tubes, leading to unpredictable damping, fragile connections, and loose wires, which affect accuracy and reliability.
Innovation Solution
A Coriolis flow meter design that incorporates a printed circuit board positioned between the flow tubes, with driver and pick-off components coupled to the PCB, eliminating the need for wires to be attached directly to the flow tubes and reducing the number of components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If wires are attached to flow tubes using tape or adhesive, then the connection is simplified, but the damping becomes unpredictable and changes with time and temperature
Solution Approach 1:
The patent introduces a flexible printed circuit board as an intermediary component between the flow tubes and the external wiring. The FPCB is attached to the flow tubes using adhesive, while providing stable electrical connections through its rigid circuit traces. This mediator separates the mechanical attachment function from the electrical connection function, allowing the adhesive to provide secure mechanical bonding without directly affecting the electrical signal paths, thus reducing unpredictable damping effects.
2Reliability
If thin flexible conductors (flexures) are used to connect wires to flow tubes, then damping is minimized, but the connections become extremely fragile and have distinct natural frequencies that can cause rapid failure
Solution Approach 1:
The patent employs a flexible printed circuit board that combines the advantages of flexible conductors with the structural integrity of a rigid circuit board. The FPCB uses thin flexible substrate material that can accommodate the movement of flow tubes while providing distributed structural support through its layered construction. This flexible film structure minimizes damping effects compared to rigid attachments while avoiding the fragility and natural frequency issues of thin wire flexures through its distributed reinforcement.
Solution Approach 2:
The flexible printed circuit board is constructed as a composite material structure with multiple layers including flexible substrate, conductive traces, and protective coatings. This composite construction provides both the flexibility needed to accommodate flow tube movement and the structural strength to prevent failure, eliminating the brittleness of single-material thin flexures while maintaining low damping characteristics.
3Ease of manufacture
If driver and pick-off components are mounted on flow tubes with loose wires, then assembly is simplified, but the loose wires cause measurement errors and reliability issues
Solution Approach 1:
The patent merges the electrical connection function with the structural support function by integrating the circuit board directly into the flow tube assembly. The FPCB is attached to the flow tubes and provides both mechanical support for the driver and pick-off components and stable electrical connections. This integration eliminates loose wires by combining multiple functions into a single unified structure, ensuring that electrical connections remain stable during flow tube vibration while maintaining assembly simplicity.
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 design stabilizes the flow meter by minimizing damping and natural frequency issues, eliminating the need for fragile wire attachments, and reducing maintenance, resulting in a more accurate and reliable measurement system.
Implementation Method 1
a driver component or a pick-off component coupled to the printed circuit board (250)
Implementation Method 2
The pick-off sensor magnet-coil assembly then produces an induced voltage which is proportional to the motion of the flow tubes
Implementation Method 3
Each conduit configuration in a Coriolis mass flow meter has a set of natural vibration modes, which may be of simple bending, torsional, or coupled type. Each conduit can be driven to oscillate at resonance in one of these natural modes
Implementation Method 4
As material begins to flow through the flow meter, Coriolis forces cause each point along the conduit to have a different phase
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A flow meter (30) is provided that includes first and second flow tubes (103, 103'). The flow meter (30) also includes a stationary plate (250). At least a portion of the stationary plate (250) is positioned between the first and second flow tubes (103, 103'). At least one of a driver component or a pick-off components is coupled to the stationary plate (250).