Current Sensor With Gapped Core and Parallel Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current detectors face issues with variations in detection accuracy due to unstable Hall element positions, difficulty in downsizing, and thickness reduction due to the need for matching end surfaces with detection surfaces, and are prone to detection errors from vibration and noise.

Innovation Solution

A current sensor design with a core member and magnetic detector that allows for parallel detection of magnetic fields, secured on a substrate, with adjustable gaps and busbar insertion, and includes redundant detection elements to stabilize position and reduce noise interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the end surfaces of the core member are matched in size to the detection surface of the Hall element, then detection accuracy is improved, but the thickness of the current detector increases

Engineering Contradiction:
Improvedetection accuracyVSAvoidthickness
Core Design Contradiction:
Measurement precisionVSLength of stationary object

Solution Approach 1:

The patent changes the detection direction from perpendicular to the detection surface (traditional Hall element configuration) to parallel with the detection surface. This dimensional change allows the magnetic field to be detected along the thickness direction of the core member, eliminating the need for large end surfaces and reducing the overall thickness of the detector while maintaining detection accuracy

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

2Device complexity

If the Hall element position is not stabilized, then device complexity is reduced, but detection accuracy varies due to vibration

Engineering Contradiction:
Improvestructure complexityVSAvoiddetection accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent replaces the mechanical positioning system (holding members and precise mechanical alignment) with a substrate-based mounting system. The Hall element is mounted on a substrate that provides stable positioning through surface mounting techniques, eliminating complex mechanical holding structures while ensuring stable detection accuracy even under vibration conditions

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

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 design achieves stable detection accuracy, miniaturization, and reduced thickness by stabilizing the magnetic detector's position, reducing vibration-induced errors, and enhancing noise resistance.

Implementation Method 1

a core member having a first gap between end surfaces and having a circular shape through which a busbar is insertable, the core member being configured to concentrate a magnetic field generated when a current to be measured passes through the busbar

Methodology Applied
Scientific EffectMagnetic field concentration: Magnetic Field

Implementation Method 2

a magnetic detector configured to detect the magnetic field concentrated by the core member. The magnetic detector has a detection surface that detects the magnetic field and detects the magnetic-field components parallel to the detection surface

Methodology Applied
Scientific EffectMagnetic field detection: Hall Effect

Data Source

PatentEP4636409A1Current sensor
Publication Date: 2025.10.22 ALPS ALPINE CO LTD
  • EP4636409A1 patent drawingFigure 1A~1B
  • EP4636409A1 patent drawingFigure 2
  • EP4636409A1 patent drawingFigure 3

AI summary

A current sensor 1 includes a core member 2 having a first gap 22 between end surfaces 21 and having a circular shape through which a busbar 4 is insertable, the core member 2 being configured to concentrate a magnetic field generated when a current to be measured passes through the busbar 4, and a magnetic detector 3 configured to detect the magnetic field concentrated by the core member 2. The magnetic detector 3 has a detection surface 31 that detects the magnetic field and detects the magnetic-field components parallel to the detection surface 31, and the detection surface 31 is disposed parallel to the direction in which the two end surfaces 21 defining the first gap 22 face each other. Accordingly, the current sensor 1 is suitable for miniaturization and reduced thickness.