Shotgun Retainer Using Halbach Magnet Array

Solution Overview

Problem

Existing shotguns lack an effective mechanism to automatically collect ejected cartridge cases, which can scatter and pose environmental and safety hazards.

Innovation Solution

A retainer system utilizing a neodymium-based magnet positioned near the ejection port to catch ejected cartridge cases, with a Halbach array configuration and magnetic shielding to minimize interference with the shotgun's mechanics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a strong magnet is used to catch ejected cartridge cases, then the collecting efficiency is improved, but the magnetic field interferes with the shotgun mechanics causing malfunction

Engineering Contradiction:

Improvecartridge case collection efficiencyVSAvoidshotgun mechanical operation

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies local quality by creating an asymmetric magnetic field distribution where one side of the magnet has strong magnetic properties for catching cartridge cases while the other side has weak or no magnetic field to avoid interfering with shotgun mechanics. This is achieved through magnetic shielding on one side and leaving the other side exposed, allowing the magnet to perform its collecting function locally without causing system-wide interference.

Inventive Principle:

Principle #3Local quality

2Reliability

If magnetic shielding is added to protect shotgun mechanics, then the reliability is improved, but the device complexity increases

Engineering Contradiction:

Improveshotgun mechanical operationVSAvoidretainer system structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent uses magnetic shielding material as an intermediary element that mediates between the strong magnet and the shotgun mechanics. The shielding acts as a buffer that allows the magnet to maintain its strong magnetic field for cartridge case collection while preventing the magnetic field from interfering with the shotgun's mechanical components, thus protecting reliability without requiring complex active control systems.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Productivity

If a magnet is positioned close to the ejection port to catch cartridges, then the collection effectiveness is improved, but the risk of magnetic interference with shotgun components increases

Engineering Contradiction:

Improvecartridge case collection efficiencyVSAvoidmagnetic interference with shotgun mechanics

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies local quality by creating an asymmetric magnetic field distribution where one side of the magnet has strong magnetic properties for catching cartridge cases while the other side has weak or no magnetic field to avoid interfering with shotgun mechanics. This is achieved through magnetic shielding on one side and leaving the other side exposed, allowing the magnet to perform its collecting function locally without causing system-wide interference.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent uses magnetic shielding material as an intermediary element that mediates between the strong magnet and the shotgun mechanics. The shielding acts as a buffer that allows the magnet to maintain its strong magnetic field for cartridge case collection while preventing the magnetic field from interfering with the shotgun's mechanical components, thus protecting reliability without requiring complex active control systems.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 retainer system effectively collects ejected cartridge cases, reducing environmental impact and safety hazards while maintaining the shotgun's operational integrity.

Implementation Method 1

the brass head of the cartridge cases is magnetic, and by using a magnet positioned close to the ejection port, the magnet is able to catch an ejected cartridge case

Methodology Applied

Scientific EffectMagnetism: Magnetism

Implementation Method 2

the magnets are arranged as a Halbach array. A Halbach array is a special arrangement of permanent magnets that augments the magnetic field on one side of the array while cancelling the field to near zero on the other side

Methodology Applied

Scientific EffectHalbach array: Halbach Array

Implementation Method 3

the core is magnetically shielded with a shield at the side face facing towards the base

Methodology Applied

Scientific EffectMagnetic shielding: Magnetic Field

Data Source

PatentEP4232769B1Retainer for catching ejected cartridge cases from shotguns

Publication Date: 2025.04.23 WECAATCH APS

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AI summary

The present invention relates to a retainer adapted for catching ejected cartridge cases from shotguns. The retainer comprises a) a base adapted for being mounted on a shotgun; and b) an elongate member adapted for being releasably fastened to said base. The elongate member comprises i) a core of one or more magnets; and ii) a cover adapted for covering said core of one or more magnet(s). The present invention relates to a retainer adapted for catching ejected cartridge cases from shotguns. The retainer comprises a) a base adapted for being mounted on a shotgun; and b) an elongate member adapted for being releasably fastened to said base. The elongate member comprises i) a core of one or more magnets; and ii) a cover adapted for covering said core of one or more magnet(s).