Tamper-Evident Closure With Irreversible Ratchet Locking

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Solution Overview

Problem

Existing tamper-evident closure systems for containers can be defeated by reversing the closure after it has been opened, allowing the gap to be closed and the system to appear as though it has not been opened, which compromises the effectiveness of the tamper-proofing.

Innovation Solution

A closure system with a cap and body design where the cap is rotatable from an initial position to a second position creating a gap, featuring a locking arrangement and an inner ratchet component with a line of weakness that breaks upon reverse rotation, and a lateral ratchet arrangement for increased resistance to resetting, ensuring the gap remains open and providing a visible indication of opening.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a closure system uses a gap-generating mechanism to indicate opening, then tamper-evident visibility is improved, but the system can be defeated by reverse rotation that closes the gap

Engineering Contradiction:

Improvetamper-evident reliabilityVSAvoidresetting ease

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The closure is divided into inner and outer parts that can rotate relative to each other. The outer part rotates to generate a gap for tamper evidence, while the inner part contains ratchet mechanisms that prevent reverse rotation. This segmentation allows the opening indication function to work independently from the prevention of resetting.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Ratchet arrangements are built into the closure structure before use, with teeth configured to engage in one direction only. These preliminary anti-actions prevent reverse rotation before it can close the gap, making the tamper evidence irreversible by design rather than requiring post-opening intervention.

Inventive Principle:

Principle #9Preliminary anti-action

2Strength

If lateral ratchet arrangements are used to prevent reverse rotation, then resistance to resetting is improved, but the ratchet arrangements can be defeated by sufficient reverse turning torque

Engineering Contradiction:

Improveresistance to reverse rotationVSAvoidanti-tamper reliability

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The closure incorporates multiple anti-tamper mechanisms working together: lateral ratchet arrangements provide initial resistance, while axial ratchet arrangements and frangible bridges provide additional layers of protection. This composite approach ensures that defeating one mechanism does not compromise the overall tamper evidence system.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The closure design anticipates attempts to overcome the ratchet arrangements by incorporating frangible bridges that break under excessive torque. This beforehand cushioning protects the critical ratchet mechanisms from being defeated by applying excessive force, as the frangible elements fail first to preserve the tamper evidence.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Loss of information

If the closure allows rotation from first position to second position to create a gap, then visual indication of opening is improved, but the closure can be rotated back to close the gap

Engineering Contradiction:

Improveopening status informationVSAvoidgap position stability

Core Design Contradiction:

Loss of informationVSStability of the object's composition

Solution Approach 1:

The closure replaces reversible mechanical rotation with irreversible mechanical engagement. Ratchet teeth and locking arrangements convert the rotational movement that creates the gap into a locked position that cannot be reversed, ensuring the gap remains open as a permanent indicator of opening status.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The ratchet locking mechanism is designed to engage automatically when the outer part rotates to the second position. This preliminary action of automatic locking ensures that once the gap is generated, the closure stabilizes in that opened state without requiring additional user action, and prevents any subsequent rotation that would close the gap.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentEP3663226B1Closure for a container neck

Publication Date: 2024.01.31 GUALA CLOSURES SPA

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AI summary

A closure (101) comprises a first portion (102) comprising a body (104) for fixing to a container neck and a second portion (103) comprising a cap (105) releasably engageable with the body (104). The closure (101) comprises a seal support portion (107) formed from a first plastics material and a seal (106) formed from a second plastics material that is more compliant than the first plastics material, the seal (106) formed integrally with the seal support portion (107). The cap (105) comprises an outer part (110) rotatable relative to an inner part (109), and a locking mechanism. The seal support portion (107) is a portion of an inner ratchet component of the inner part (109). A method of forming the closure (101) comprising the step of bi-injection moulding the seal support portion (107) and the seal (106). A container comprising a container neck provided with the closure (101).