Differential Pressure Measuring Cell Overload Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Differential pressure measuring cells face challenges in withstanding static overloads, leading to stress peaks and potential destruction at joints, particularly due to the loading of static pressure on the measuring membrane and opposing bodies, which existing solutions fail to adequately address without increasing costs or compromising performance.
Innovation Solution
The design incorporates a decoupling chamber with a larger diameter than the measuring chamber, connected via an equalizing duct, and featuring relief grooves and membrane beds that support the measuring membrane during overloads, reducing notch stresses and allowing for even pressure distribution across the differential pressure measuring cell.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If overload membranes are used to protect the differential pressure sensor, then the sensor can withstand static overloads, but the device dimensions increase and costs increase
Solution Approach 1:
The invention extracts the overload protection function from the traditional overload membrane approach and integrates it directly into the opposing bodies structure. The opposing bodies are designed with a specific geometry that provides overload protection without requiring separate overload membranes, thereby reducing device dimensions while maintaining protection capability.
Solution Approach 2:
The opposing bodies serve multiple functions: they provide structural support, enable pressure transmission, and provide overload protection. By making the opposing bodies multi-functional, the invention eliminates the need for separate overload protection components, reducing overall device volume.
2Reliability
If overload membranes are used to protect the differential pressure sensor, then the sensor can withstand static overloads, but the measuring element dynamics are negatively affected
Solution Approach 1:
The invention removes the overload membrane component that was causing dynamic degradation and replaces it with a geometric design feature of the opposing bodies. This extraction of the problematic component restores measuring element dynamics while maintaining overload protection through the modified opposing body structure.
3Strength
If the measuring membrane is supported by membrane beds during overloads, then the bursting stress is prevented, but stress peaks occur at the joints between the measuring membrane and opposing bodies
Solution Approach 1:
The invention applies local quality by creating a specific geometric configuration in the opposing bodies that provides support to the measuring membrane at critical locations. The opposing bodies have a geometry that distributes stress evenly and prevents stress peaks at the joints while maintaining membrane support capability.
4Stress or pressure
If static pressure is introduced into the differential pressure measuring cell, then the measuring membrane and opposing bodies are loaded, but stress peaks occur at the joints leading to potential destruction
Solution Approach 1:
The opposing bodies are designed with a specific local geometry that optimizes stress distribution under static pressure. This geometric design prevents stress concentration at the joints, allowing the cell to withstand high static pressures without compromising joint strength.
Solution Approach 2:
The invention employs curved or rounded geometries in the opposing bodies design to eliminate sharp corners and edges that would concentrate stress. This curvature approach distributes stress evenly across the structure, preventing stress peaks at the joints under static pressure loading.
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 configuration enhances the cell's resistance to static overloads, minimizing stress peaks and maintaining measurement accuracy while reducing costs by minimizing the volume of the decoupling chamber and using compatible filling materials, thus providing an overload-proof differential pressure measuring cell.
Implementation Method 1
the decoupling chamber has, in a plane parallel to the measuring membrane, a diameter that is larger than the diameter of the equalizing duct
Implementation Method 2
the measuring membrane is to be supported, in case a limit value for a unilateral overpressure is exceeded, by the membrane bed
Implementation Method 3
the chamber section has at least one equalizing duct by means of which the measuring chamber communicates with the decoupling chamber
Implementation Method 4
the converter is provided in order to convert a deformation of the measuring membrane, which deformation is dependent upon a difference between the first pressure (p1) and the second pressure (p2), into an electrical signal
Data Source
AI summary
A differential pressure measuring cell comprises a measuring membrane; two opposing bodies; and one converter. The measuring membrane is arranged between the opposing bodies and is connected in a pressure-tight manner to the two opposing bodies, forming in each case one measuring chamber. The opposing bodies each have a pressure duct through which a pressure can be made to act upon the respective measuring chamber. The converter is provided in order to convert a deformation of the measuring membrane, which deformation is dependent upon a difference between the pressures, into an electrical signal; wherein the opposing bodies each have a chamber section oriented toward the measuring membrane and a rear wall section oriented away from the measuring membrane with, between these, a decoupling chamber. The chamber sections each have an equalizing duct between the measuring chamber and the decoupling chamber, wherein the decoupling chamber has a diameter that is at least as large as the diameter of the measuring chamber.