Karabiner Dual-Sleeve Locking Mechanism for Vibration Resistance

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Solution Overview

Problem

Existing karabiner designs, such as screwgate, Twistlock, Ball-lock, and Magnatron, face issues with reliability in adverse conditions and difficulty in one-handed operation, particularly due to mechanical failures and frictional contact leading to unintended unlocking.

Innovation Solution

A karabiner design featuring a primary sleeve with a coarse internal thread and a secondary sleeve with a finer external thread, allowing for one-handed operation and enhanced locking security through sequential movement of the sleeves, with the secondary sleeve preventing the primary sleeve from loosening.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a threaded sleeve is provided for screwing over the free end of the gate portion to lock the gate closed, then the karabiner can be locked in the closed position, but the threaded sleeve can move by frictional contact with other equipment, by vibration, or through inadequate tightening

Engineering Contradiction:

Improvelocking reliabilityVSAvoidoperation simplicity

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The locking mechanism is divided into two independent threaded sleeves: a first sleeve that engages with the gate portion to lock it closed, and a second sleeve that engages with the first sleeve to prevent unintended unlocking. This segmentation allows each component to have a specialized function, improving overall reliability while maintaining operational simplicity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second sleeve is pre-configured to engage with the first sleeve and prevent backward rotation. This preliminary action ensures that even if the first sleeve becomes loose due to vibration or frictional contact, the second sleeve maintains the locked position and prevents accidental opening.

Inventive Principle:

Principle #10Preliminary action

2Reliability

If Twistlock karabiners with a sliding locking sleeve are used, then automatic locking is achieved, but they are very difficult to use one handed and do not lock when exposed to grit which stops the spring from working

Engineering Contradiction:

Improveautomatic lockingVSAvoidone-handed operation

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent replaces the spring-based automatic locking mechanism with a threaded engagement system. The operator simply rotates the first sleeve to engage threads, creating a positive mechanical lock that does not rely on springs or complex mechanisms, enabling reliable one-handed operation.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If Ball-lock karabiners are used, then reliability is improved compared to screwgate, but they cannot be operated using one hand

Engineering Contradiction:

Improvelocking reliabilityVSAvoidone-handed operation

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

Inventive Principle:

Principle #1Segmentation

4Ease of operation

If Magnatron karabiners with two small levers and embedded magnets are used, then one-handed operation is achieved, but they have mechanical parts that can fail and are less reliable in adverse conditions

Engineering Contradiction:

Improveone-handed operationVSAvoidmechanical failure resistance

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The patent replaces the magnet-based lever system with a purely threaded mechanical engagement system. The two sleeves engage through threaded connections that provide positive mechanical locking, eliminating reliance on magnetic forces or complex lever mechanisms that can fail in adverse 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 provides reliable one-handed operation and enhanced locking security, maintaining the ease of use of standard screwgate karabiners while improving reliability in adverse conditions and preventing unintended unlocking.

Implementation Method 1

The problem with the above design is that, in use, the threaded sleeve can move by frictional contact with other equipment

Methodology Applied

Scientific EffectFriction: Friction

Implementation Method 2

The threaded sleeve can move by frictional contact with other equipment, by vibration, or through inadequate tightening of the sleeve

Methodology Applied

Scientific EffectFriction: Friction

Data Source

PatentEP2997270B1Improvements in karabiners

Publication Date: 2019.12.04 ROGELJA ANDREW

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AI summary

A karabiner (10) comprises a body portion (12) and a gate portion (16) which is mounted to the body portion about a pivot (18), the gate (16) defining a free end (20) which is arranged to inter-engage with a nose (22) of the body portion to define a closed ring for receiving a rope (50) passing therethrough and including a first sleeve (26) which, when the ring is closed, is moveable between a first position where the gate is free to rotate about the pivot in at least one direction, and a second position where the sleeve at least partly encloses the free end of the gate and the nose and substantially prevents rotation of the gate about the pivot, and further including a second sleeve (28) which is internally threaded and which is mounted on an externally threaded portion (30) of the gate for movement towards and away from the free end of the gate and which may be rotated towards the first sleeve when the first sleeve is in the second position, to prevent movement of the sleeve into first position in which the gate is free to rotate.