Carabiner Lever Geometry for Easier One-Hand Opening

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Solution Overview

Problem

Existing carabiners, particularly those designed for via ferratas, face challenges in ease of operation due to the locking lever often requiring direct finger contact with the steel cable, and the need for additional actuators complicates the mechanism.

Innovation Solution

The carabiner design features a significantly larger distance between the actuating bolt and actuating lever pivot axis compared to the locking lever pivot axis, allowing a small angle pivot of the actuating lever to fully open the locking lever, with the actuating and locking levers on the same side for intuitive operation, and includes a polymer coating to reduce abrasion and noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the locking lever is made long to prevent finger contact with steel cable, then safety is improved, but the device complexity increases

Engineering Contradiction:
ImprovesafetyVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

An actuating lever is introduced as an intermediary component between the user's fingers and the locking lever. The actuating lever transmits the opening force to the locking lever through an actuating bolt, allowing the locking lever to remain long for safety while the user operates from a safe distance.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If the actuating lever and locking lever are placed on opposite sides, then the locking mechanism is more secure, but the ease of operation decreases

Engineering Contradiction:
Improvelocking securityVSAvoidease of operation
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The actuating lever and locking lever are positioned on the same side of the carabiner body, merging their operational zones. This allows the user to operate both levers with the same hand without complex finger movements, significantly improving ease of operation while maintaining locking security through the mechanical engagement of the locking element.

Inventive Principle:
Principle #5Merging (Combining)

3Ease of operation

If the distance between actuating bolt and actuating lever pivot axis is increased, then the ease of operation is improved, but the device complexity increases

Engineering Contradiction:
Improveease of operationVSAvoiddevice complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The actuating slot is designed with a specific geometric shape that converts the rotational movement of the actuating lever into linear movement of the actuating bolt. This dimensional transformation allows for a larger effective lever arm distance, improving mechanical advantage and ease of operation without adding complex separate mechanisms.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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

This design enables easy and intuitive operation with reduced friction, enhancing usability and durability while maintaining secure locking and minimizing noise during use.

Implementation Method 1

the actuating lever (5) can be pivoted from the closed position to the maximum open position about an actuating lever pivot axis (8)

Methodology Applied
Scientific EffectLever: Lever

Implementation Method 2

The actuating lever (5) acts on the locking lever (3) by means of an actuating bolt (10) guided in an actuating slot (9)

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 3

the locking lever (3) is pivotably mounted on the hook-shaped base body (2) between a closed position and a maximum open position by means of a locking lever pivot axis (7)

Methodology Applied
Scientific EffectLever: Lever

Implementation Method 4

the locking lever (3) can be locked in the closed position by the locking element (4)

Methodology Applied
Scientific EffectMechanical Fastener: Mechanical Fastener

Implementation Method 5

incorporating a polymer coating for reduced abrasion and noise

Methodology Applied
Scientific EffectAbrasion: Abrasion

Data Source

PatentEP4610505B1Carabiner
Publication Date: 2026.04.22 ABA HORTNAGL
  • EP4610505B1 patent drawingFigure 1~3
  • EP4610505B1 patent drawingFigure 4~6
  • EP4610505B1 patent drawingFigure 7~8

AI summary

A snap hook (1) with a hook-shaped base body (2) and a locking lever (3), a locking part (4), and an actuating lever (5), wherein the hook-shaped base body (2) partially encloses a receiving opening (6) of the snap hook (1), and the locking lever (3) is pivotably mounted on the hook-shaped base body (2) between a closed position and a maximum open position by means of a locking lever pivot axis (7), wherein the locking lever (3) can be locked in the closed position by the locking part (4), and the locking lever (3) can be pivoted from the closed position to the maximum open position by means of the actuating lever (5), which is pivotably mounted on the hook-shaped base body (2) by means of an actuating lever pivot axis (8), and the actuating lever (5) acts on the locking lever (3) by means of an actuating bolt (10) guided in an actuating slot (9), for pivoting.wherein, at least in the closed position, a distance (11) of the actuating bolt (10) from the actuating lever pivot axis (8) is at least three times, preferably at least five times, greater than a distance (12) of the actuating bolt (10) from the locking lever pivot axis (7).