Offset Broken Ring Assemblies for Tamper-Evident Security

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing tamper-evident ring assemblies often require high security and sophistication, but there is a need for a low-cost, single-use solution that provides clear indication of tampering and can be easily opened manually without tools.

Innovation Solution

A tamper-evident, single-use ring assembly composed of interengaging broken rings made from different materials, where the break in one ring is offset from the other, allowing for resilient stress and easy manual opening by cutting, providing a strong and wear-resistant design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If high security and sophistication are used in tamper-evident ring assemblies, then security level is improved, but cost and complexity increase

Engineering Contradiction:
Improvesecurity levelVSAvoidcomplexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The ring assembly is divided into two separate broken rings (first and second rings) made of different materials. Each ring has its own break offset from the other, creating a segmented structure that provides security through material differences while maintaining simplicity in assembly and opening procedures

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The assembly uses composite construction with two rings of different materials (e.g., metal and plastics). This provides enhanced security through material property differences (strength, wear resistance) while keeping the overall design simple and the cost relatively low compared to high-security alternatives

Inventive Principle:
Principle #40Composite materials

2Ease of operation

If tool-free manual opening is enabled, then ease of operation is improved, but security may be compromised

Engineering Contradiction:
Improveease of openingVSAvoidsecurity
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The opening function is extracted as a separate action from the normal wear function. The rings are designed to be opened by cutting at the offset break locations, which is a deliberate tampering action rather than normal use. This allows easy manual opening when needed while maintaining security during normal operation

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The rings have different material properties at different locations - the breaks are positioned at specific locations offset from each other, creating local weaknesses that facilitate opening. The majority of the ring structure maintains full strength and security properties, while only the localized break regions are designed for opening

Inventive Principle:
Principle #3Local quality

3Reliability

If single-use design is implemented, then tamper indication is improved, but durability is reduced

Engineering Contradiction:
Improvetamper indicationVSAvoiddurability
Core Design Contradiction:
ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The ring assembly is designed as a disposable single-use security device. The rings are made from relatively inexpensive materials (metal and plastics) and are intended to be opened by cutting rather than reused. This provides clear tamper indication while keeping costs low, accepting that the device will not be durable after opening

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

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 assembly offers a low-cost, tool-free, and tamper-evident solution with clear indication of tampering, suitable for various applications, including key rings, with enhanced strength and wear resistance.

Implementation Method 1

the first broken ring being resiliently stressed in its assembled state such that, upon cutting through of the ring assembly, the confronting ends of the assembly move apart in a direction with a major component perpendicular to the plane of the ring

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3152749B1Tamper-evident ring assemblies
Publication Date: 2022.12.28 ASSA ABLOY LTD
  • EP3152749B1 patent drawingFigure 1~2
  • EP3152749B1 patent drawingFigure 3~4B
  • EP3152749B1 patent drawingFigure 5~6B

AI summary

A tamper-evident, single use, ring assembly, is assembled from first and second interengaging broken rings (1, 2). The first broken ring (1) is of a first material and the second broken ring (2) is of a second material. A break in the ring of the first material is offset circumferentially from a break in the ring of the second material. The assembly of the rings forms a closed ring assembly which can be cut through in the region of the break in the ring of the first material to open the ring assembly. At least one of the rings (1, 2) of the ring assembly is resiliently stressed in its assembled state such that, upon cutting through of the ring assembly, the confronting ends of the assembly move apart.