Snap Hook Linkage for Fall-Load Stress Redirection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current snap hooks used for fall protection lack effective mechanisms to redirect bending stress during a fall event and provide adequate protection against accidental activation, leading to potential failure in critical situations.

Innovation Solution

A snap hook design featuring a pivoting connection link that redirects forces to a central pivot point, incorporating a deformable material to absorb energy and indicate usage, and an interlocking gate-nose geometry for increased strength, along with a trigger guard to prevent accidental activation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a traditional snap hook design is used, then the structure is simple and easy to manufacture, but it lacks effective mechanisms to redirect bending stress during a fall event, leading to potential failure

Engineering Contradiction:
Improvestress redistribution capabilityVSAvoidstructural complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The connection link is designed to pivot about a central portion of the body, allowing the structure to dynamically redirect bending stresses during a fall event. This dynamic movement enables stress redistribution from the lower portion to the central portion, improving strength without requiring complex static structures.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The body is divided into distinct portions (upper, lower, and central) with the connection link as a separate movable component. This segmentation allows the central portion to serve as a dedicated stress redistribution point while keeping the overall structure relatively simple.

Inventive Principle:
Principle #1Segmentation

2Reliability

If no trigger guard is provided, then the device complexity is reduced and manufacturing is easier, but accidental activation cannot be prevented

Engineering Contradiction:
Improveprotection against accidental activationVSAvoidtrigger mechanism complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The connection link serves as an intermediary trigger guard that physically protects the trigger mechanism. By positioning the connection link to guard the trigger, accidental activation is prevented without requiring a separate dedicated guard component, thus maintaining relatively simple device complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Strength

If the connection link is rigidly fixed, then the structure is simpler and manufacturing is easier, but bending stress during fall cannot be redirected, potentially causing failure

Engineering Contradiction:
Improvefall stress resistanceVSAvoidassembly complexity
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The connection link is pivotally coupled rather than rigidly fixed, enabling it to rotate and redirect forces during a fall. This pivotal connection provides the necessary dynamic stress redirection capability while maintaining relatively simple assembly processes.

Inventive Principle:
Principle #15Dynamics

4Ease of operation

If the gate and body form a permanently closed configuration, then the hook connection passage is always protected, but access for connection and release is not provided

Engineering Contradiction:
Improveconnection and release accessibilityVSAvoidhook connection passage protection
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The gate is designed to pivot between closed and open configurations, allowing dynamic access control. When closed, the gate protects the hook connection passage; when opened, it provides access for connection and release operations. The locking member ensures the gate remains securely closed during normal operation.

Inventive Principle:
Principle #15Dynamics

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 reduces bending stress on the snap hook during a fall, ensures safe and ergonomic operation, and prevents accidental triggering, enhancing the overall safety and reliability of the fall protection system.

Implementation Method 1

The upper end of the connection link is pivotally coupled proximate the central portion of the body

Methodology Applied
Scientific EffectPivoting: Hinge

Implementation Method 2

incorporating a deformable material to absorb energy and indicate usage

Methodology Applied
Scientific EffectDeformation: Deformation

Implementation Method 3

a spring activated trigger and latch mechanism

Methodology Applied
Scientific EffectSpring: Spring

Implementation Method 4

a trigger latch mechanism

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3650717B1Snap hook
Publication Date: 2023.04.26 D B INDUSTRIES LLC
  • EP3650717B1 patent drawingFigure 1A~1B
  • EP3650717B1 patent drawingFigure 2A~2B
  • EP3650717B1 patent drawingFigure 3

AI summary

A snap hook (100) that includes a body, a gate (180), a connection link (200) and a breakable fastener (220) is provided. A central portion of the body is positioned between an upper portion and a lower portion. The gate is pivotally coupled proximate the central portion of the body. The gate and the body selectively forming a closed configuration that defines a hook connection passage and an open configuration that provides access to the hook connection passage. An upper end of the connection link is pivotally coupled proximate the central portion of the body. A lower end of the connection link includes a body connection aperture (203). The breakable fastener couples the lower end of the connection link proximate the lower portion of the body. The breakable fastener is configured to break when a select amount of force is applied to the lower end of the connection link to transfer the force from the lower portion of the body to the central portion of the body.