Inductor Iron Core End Clamping for Air Gap Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The production of electrical inductances, particularly chokes and filters, faces challenges in reducing costs and optimizing function due to complex assembly processes and the need for precise air gap management in iron cores, which affects magnetic resistance and damping behavior.

Innovation Solution

The design features yokes with extensions at the ends that hold the iron core together, allowing for adjustable air gaps and non-penetrating clamping, enabling easier assembly and improved magnetic field homogeneity without through-holes, thus reducing noise emissions and enhancing operational efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the iron core is assembled from individual sheets with through-holes for screws and welding, then the sheets can be securely joined together, but the manufacturing complexity and production time increase significantly

Engineering Contradiction:
Improvejoint strength of sheet metal stackVSAvoidassembly process complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The invention extracts and eliminates the need for through-holes, screws, and welding operations by introducing a clamping device that applies pressure from the ends of the laminated core. This removes the complex joining operations while maintaining structural integrity through end-clamping of the sheet stack.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The clamping device acts as an intermediary mechanism that transmits clamping force through the entire sheet metal stack from the ends, securing all sheets together without requiring penetration or joining operations at multiple points throughout the structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If air gaps are created between individual sheets using spacers, then magnetic resistance is reduced and damping behavior is optimized, but the assembly precision and production time increase

Engineering Contradiction:
Improvemagnetic damping performanceVSAvoidair gap uniformity
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

Spacers are inserted between individual sheets during the stacking process to pre-establish the required air gaps before the clamping device is applied. This preliminary action ensures uniform magnetic resistance and damping characteristics throughout the laminated core.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The invention applies local air gaps between specific sheets rather than uniform spacing throughout, allowing optimization of magnetic damping performance in critical areas while maintaining overall structural integrity and magnetic flux paths.

Inventive Principle:
Principle #3Local quality

3Strength

If mounting brackets and attachments are screwed or welded to the inductor, then the mechanical strength and stability are improved, but the production cost and manufacturing time increase

Engineering Contradiction:
Improvemechanical stability of inductorVSAvoidproduction efficiency
Core Design Contradiction:
StrengthVSProductivity

Solution Approach 1:

The clamping device is designed to integrate mounting brackets and attachments directly into the clamping mechanism, combining the functions of sheet stacking, clamping, and attachment mounting into a single operational system that reduces production steps.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The clamping device serves multiple functions simultaneously: it secures the sheet metal stack, maintains air gaps, and provides mounting points for brackets and attachments, eliminating the need for separate joining and mounting operations.

Inventive Principle:
Principle #6Universality (Multi-functionality)

4Use of energy by moving object

If the iron core is completely enclosed to minimize magnetic resistance, then transformer efficiency is improved, but chokes and filters require air gaps for damping which reduces efficiency

Engineering Contradiction:
Improvetransformer efficiencyVSAvoiddamping performance for chokes and filters
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The invention applies local air gaps between specific sheets rather than uniform spacing throughout, allowing optimization of magnetic damping performance in critical areas while maintaining overall structural integrity and magnetic flux paths.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The clamping device allows dynamic adjustment of the degree of enclosure, enabling the iron core to be completely enclosed for transformers when efficiency is paramount, or to include air gaps for chokes and filters when damping performance is required.

Inventive Principle:
Principle #15Dynamics

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 simplifies assembly, reduces production costs, and improves the functional performance of inductances by allowing customizable air gaps and homogeneous magnetic fields, leading to lower noise emissions and optimized damping behavior.

Implementation Method 1

The coil is positioned above the iron core in such a way that a magnetic flux is generated in the iron core due to the applied coil voltage and the resulting induction.

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

To prevent eddy currents, this device is typically manufactured from a stack of individually rolled sheets, known as dynamo sheets or transformer sheets, placed on top of each other. The individual sheets must be electrically insulated from one another.

Methodology Applied
Scientific EffectEddy currents: Eddy Currents

Data Source

PatentEP3021332B1Inductivity and method for producing same
Publication Date: 2019.09.18 MICHAEL RIEDEL TRANSFORMATORENBAU
  • EP3021332B1 patent drawingFigure 1
  • EP3021332B1 patent drawingFigure 2a~2b
  • EP3021332B1 patent drawingFigure 2c

AI summary

To improve the function of an electrical inductor, the parts of the iron core (24) are held in the coil unit (31) by means of a form-fit connection through appropriate construction of the inductor.