Non-Divided Noise Filter Core for Bent Busbar Connection

Solution Overview

Problem

Bent-shaped busbars face insertion issues in magnetic cores of noise filters, leading to reduced noise reduction effects due to increased inner diameter or divided magnetic core structures, which compromise impedance and permeability.

Innovation Solution

A non-divided magnetic core with conductive coupling terminals and a holding portion, allowing busbars to be connected through the core's through-hole without compromising noise reduction, using a housing and locking mechanism to secure the terminals in place.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the inner diameter dimension of the through-hole of the magnetic core is increased to accommodate bent-shaped busbars, then the busbar can pass through, but the impedance of the magnetic core decreases and the noise reduction effect deteriorates

Engineering Contradiction:

Improvebusbar insertionVSAvoidnoise reduction effect

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The through-hole is divided into multiple sections with different inner diameter dimensions. The first section has a smaller inner diameter for noise reduction, while the second section has a larger inner diameter to accommodate bent busbars. This segmentation allows each section to fulfill its specific function without compromising the overall performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the through-hole have different local qualities in terms of inner diameter dimension. The first section maintains a smaller diameter to preserve magnetic core impedance, while the second section provides a larger diameter for busbar insertion. This local differentiation resolves the contradiction between noise reduction and ease of installation.

Inventive Principle:

Principle #3Local quality

2Ease of operation

If the magnetic core has a divided structure to accommodate bent-shaped busbars, then the busbar can pass through, but the magnetic permeability of the magnetic core decreases and the noise reduction effect deteriorates

Engineering Contradiction:

Improvebusbar insertionVSAvoidnoise reduction effect

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The through-hole is segmented into multiple sections with different inner diameter dimensions. The first section has a smaller inner diameter for noise reduction, while the second section has a larger inner diameter to accommodate bent busbars. This segmentation allows each section to fulfill its specific function without compromising the overall performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the through-hole have different local qualities in terms of inner diameter dimension. The first section maintains a smaller diameter to preserve magnetic core impedance, while the second section provides a larger diameter for busbar insertion. This local differentiation resolves the contradiction between noise reduction and ease of installation.

Inventive Principle:

Principle #3Local quality

3Reliability

If a non-divided type magnetic core is used to maintain noise reduction effect, then the magnetic permeability and impedance are preserved, but bent-shaped busbars cannot pass through the through-hole

Engineering Contradiction:

Improvenoise reduction effectVSAvoidbusbar insertion

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The through-hole is segmented into multiple sections with different inner diameter dimensions. The first section has a smaller inner diameter for noise reduction, while the second section has a larger inner diameter to accommodate bent busbars. This segmentation allows each section to fulfill its specific function without compromising the overall performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the through-hole have different local qualities in terms of inner diameter dimension. The first section maintains a smaller diameter to preserve magnetic core impedance, while the second section provides a larger diameter for busbar insertion. This local differentiation resolves the contradiction between noise reduction and ease of installation.

Inventive Principle:

Principle #3Local quality

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 maintains noise reduction efficacy while enhancing busbar shape flexibility and ensuring secure terminal positioning, even under external forces.

Implementation Method 1

a magnetic core having a through-hole, and is used by passing the busbar through the through-hole of the magnetic core

Methodology Applied

Scientific EffectMagnetic shielding: Magnetic Field

Data Source

PatentEP4163936B1Noise filter

Publication Date: 2025.09.03 KITAGAWA INDS

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AI summary

There is provided a noise filter. A noise filter according to the present disclosure includes: a non-divided type magnetic core in which a through-hole having a first opening and a second opening at respective ends of the through-hole is formed; a conductive coupling terminal including a first connection portion and a second connection portion at respective ends of the conductive coupling terminal, the first connection portion and the second connection portion being connectable to busbars, the conductive coupling terminal being disposed inside the through-hole; and a holding portion that holds the coupling terminal disposed inside the through-hole. The coupling terminal is held to the magnetic core by the holding portion in a state where the first connection portion faces the first opening from inside of the through-hole and the second connection portion faces the second opening from inside of the through-hole.