Bracelet Clasp With Rotating Inner Sleeve and Magnetic Lock

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing bracelet or chain clasps for cable-like bands are not ergonomically comfortable, aesthetically appealing, and hygienic, with limited locking security and increased manufacturing costs, especially when used for thicker bands or as bracelets or chains.

Innovation Solution

A bracelet or chain clasp with a two-part closure system featuring a non-positive magnetic connection and positive engagement elements, where the inner sleeve rotates within the outer sleeve, providing a secure and gap-free connection while allowing for easy closure and avoiding twisting of the band, and using magnets and magnetizable materials for enhanced holding power without visible gaps.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a purely magnetic connection is used for closure, then the clasp is easy to operate and compact, but the locking security is insufficient for thicker rope-like bands

Engineering Contradiction:
Improveease of closureVSAvoidlocking security
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent combines magnetic connection and mechanical positive-locking engagement in a single clasp system. The magnetic attraction provides initial holding force and ease of closure, while the mechanical engagement elements (protrusions and recesses) provide secure locking for thicker bands, merging both connection types to resolve the contradiction between ease of operation and locking security.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The clasp is divided into two functional components: a magnetic connection system for initial attraction and holding, and a separate mechanical positive-locking system with engagement elements. This segmentation allows each component to optimize its specific function while working together to provide both ease of operation and reliable locking.

Inventive Principle:
Principle #1Segmentation

2Ease of manufacture

If traditional jewelry clasps with exposed surfaces are used, then the structure is simple to manufacture, but the surfaces are not sealed allowing dirt and perspiration to penetrate, reducing hygiene and wearing comfort

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoiddirt and perspiration penetration
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The patent employs sealed hollow body structures with recesses that receive and secure the rope-like band ends. These enclosed spaces act as protective barriers that prevent dirt and perspiration from penetrating into the clasp mechanism, while the overall clasp structure remains relatively simple to manufacture using standard forming techniques.

Inventive Principle:
Principle #30Flexible shells and thin films

3Adaptability or versatility

If eyelets are added to the clasp for hooking chains, then the versatility is improved, but the eyelets are only suitable for thicker rope-like cords to a very limited extent and affect the aesthetic appearance

Engineering Contradiction:
Improvechain hooking capabilityVSAvoidaesthetic appearance
Core Design Contradiction:
Adaptability or versatilityVSShape

Solution Approach 1:

The hollow body structures with recesses serve multiple functions: they secure the rope-like band ends through the magnetic and mechanical connection systems, and simultaneously provide attachment points for chain links or other jewelry components. This multi-functionality eliminates the need for separate eyelets while maintaining aesthetic appearance and versatility.

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

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 improves ergonomics and wearing comfort, enhances locking security, and simplifies manufacturing while maintaining a visually appealing and hygienic design, ensuring a secure and gap-free connection that prevents dirt and sweat ingress.

Implementation Method 1

interacts with the first closure part via a force-fit, magnetically formed connection

Methodology Applied
Scientific EffectMagnetic connection: Magnetism

Data Source

PatentEP3287034B1Wristband or chain clasp
Publication Date: 2019.07.10 FISCHERS FRITZE GMBH
  • EP3287034B1 patent drawingFigure 1-1~3-3
  • EP3287034B1 patent drawingFigure 4~6

AI summary

In a bracelet or chain clasp (2) for rope-like bands (4) used as a bracelet or chain in the form of rope or leather bands, comprising a first closure part (8) for receiving a first end of the rope-like band (4) and a second closure part (30) which interacts with the first closure part (8) via a force-locking (magnetic) connection for receiving a second end of the rope-like band (4), the ergonomics and wearing comfort are to be improved, its closing security increased and its manufacture facilitated.This is achieved by the first locking part (8) being designed in two parts with an inner sleeve (10) and an outer sleeve (20) and the outer sleeve (20) being pushed over the inner sleeve (10), wherein the inner sleeve (10) and the outer sleeve (20) are arranged to be rotatable and/or axially slidable relative to each other, and in addition to the magnetic connection, the first locking part (8) and the second locking part (30) have positively interlocking engagement elements (26, 34), wherein when the clasp is closed the positively interlocking engagement elements (26, 34) engage with each other.