3D-Printed Ceramic Coil Formers for High-Temperature Flow Meters

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Solution Overview

Problem

Existing coil arrangements for Coriolis and magnetic-inductive flowmeters face challenges in precision and complexity of manufacturing, particularly with ceramic coil formers, which are sensitive to temperature and require intricate structures for high-temperature applications.

Innovation Solution

Utilizing additive manufacturing processes, specifically stereolithography or 3D printing, to create ceramic coil formers with irregular or regular structures, allowing for lighter, more cost-effective, and thermally stable coil assemblies with integrated casings and fastening elements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If injection molding process is used to manufacture ceramic coil formers, then the manufacturing process is established, but the shape precision and contour quality are limited by mold quality and the process is complex

Engineering Contradiction:
Improvecontour precisionVSAvoidmanufacturing process complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical injection molding process with an additive manufacturing process (3D printing). This substitution eliminates the need for physical molds and their associated quality limitations, allowing direct digital fabrication of complex ceramic coil former geometries with high contour precision while simplifying the manufacturing process.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the manufacturing parameters from traditional subtractive or formative methods (injection molding) to additive manufacturing parameters. This enables precise control over the ceramic material deposition, achieving superior contour accuracy and eliminating mold-related limitations while reducing process complexity through digital modeling and direct printing.

Inventive Principle:
Principle #35Parameter changes

2Strength

If solid ceramic material is used for coil formers, then structural strength is ensured, but weight increases and material usage increases

Engineering Contradiction:
Improvestructural strengthVSAvoidcoil assembly weight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The patent employs porous ceramic materials or ceramic materials with internal lattice structures for the coil formers. These porous structures maintain the necessary mechanical strength and structural integrity while significantly reducing the overall weight and material consumption compared to solid ceramic constructions, achieving an optimal strength-to-weight ratio.

Inventive Principle:
Principle #31Porous materials

Solution Approach 2:

The patent segments the ceramic coil former into a lattice or cellular structure rather than using solid material. This segmentation creates a lightweight framework that preserves structural strength through geometric distribution of load paths while minimizing material usage and reducing the overall weight of the coil assembly.

Inventive Principle:
Principle #1Segmentation

3Strength

If regular dense structure is used in coil former, then mechanical strength is maintained, but material usage increases and manufacturing complexity increases

Engineering Contradiction:
Improvemechanical strengthVSAvoidmaterial usage
Core Design Contradiction:
StrengthVSLoss of substance

Solution Approach 1:

The patent utilizes porous ceramic materials that provide adequate mechanical strength through their controlled pore structures. The porosity reduces material usage while maintaining structural integrity through the strategic distribution of material in load-bearing regions, eliminating the need for fully dense material throughout the entire component.

Inventive Principle:
Principle #31Porous materials

Solution Approach 2:

The patent transitions from thinking about material distribution in two dimensions (solid vs. hollow) to three-dimensional lattice structures. This dimensional approach allows material to be strategically placed only where structurally necessary, reducing overall material usage while maintaining strength through spatial optimization of the ceramic framework.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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 enables high-temperature-resistant, lightweight, and cost-effective coil assemblies with reduced material usage, minimizing mechanical stresses and enhancing vibration behavior in Coriolis flow meters.

Implementation Method 1

the coil former is manufactured by means of an additive manufacturing process

Methodology Applied
Scientific Effect3D Printing: 3D Printing

Implementation Method 2

Ceramics are significantly less sensitive to temperature than plastics, so even measurement environments with temperatures exceeding 400°C pose no problem for the coil formers

Methodology Applied
Scientific EffectThermal Insulation: Thermal Insulation

Implementation Method 3

In magnetic-inductive flowmeters, coil assemblies are required to generate a magnetic field that penetrates the measuring tube

Methodology Applied
Scientific EffectMagnetic Field: Magnetic Field

Data Source

PatentEP4257933B1Coil arrangement for a flow meter and method for producing a coil arrangement
Publication Date: 2025.11.12 KROHNE AG
  • EP4257933B1 patent drawingFigure 1~2
  • EP4257933B1 patent drawingFigure 3~4
  • EP4257933B1 patent drawingFigure 5a~5b

AI summary

The invention relates to a coil arrangement (1) for a flow meter (2), in particular a Coriolis flow meter or a magnetic-inductive flow meter, comprising a coil (3), wherein the coil (3) has a coil former (4) and at least one coil turn (5) made of an electrically conductive material. The objective of providing a coil arrangement (1) that is advantageous compared to coil arrangements known from the prior art is achieved by manufacturing the coil former (4) from a ceramic material and by producing the coil former (4) using an additive manufacturing process. Furthermore, the invention relates to a flow meter (2) with a corresponding coil arrangement (1) and to a method (100) for manufacturing a corresponding coil arrangement (1).