Single-Lug Load Release Mechanism With Vertical Hook Restraint

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing restrain and release mechanisms for externally airborne loads face challenges in achieving precise geometric alignment, require significant clearance for easy coupling, are cumbersome and expensive, and lack efficient stress transfer and quick coupling capabilities.

Innovation Solution

A mechanism featuring vertical shift means to lift the hook from a lowered to a raised position, using a system with a push rod, return spring, and shape memory material for actuation, along with a screw and wedge principle for efficient load transfer and stabilization, ensuring quick coupling and stable transport.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the hook is kept in a lowered position for easy coupling, then the clearance between hook and load ring is maintained for friction-less insertion, but the load cannot be securely pressed against support arms for stable transport

Engineering Contradiction:
Improvecoupling easeVSAvoidload stability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The hook is designed to be dynamically positionable between a lowered coupling position and a raised transport position. The vertical shift means enable the hook to move vertically along the support arm, transitioning from a position that facilitates easy load insertion to a position that secures the load during transport, thus resolving the contradiction between ease of operation and load stability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The vertical shift means are configured to automatically or pre-position the hook in the lowered position during the coupling phase, ensuring proper alignment and clearance with the load ring before the load is attached. After coupling, the hook can then be shifted to the raised position to secure the load, performing the positioning action in advance of each operational phase.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If multiple support arms with individual displacement mechanisms are used to stabilize the load, then the load can be secured during transport, but the device becomes cumbersome and expensive with increased maintenance requirements

Engineering Contradiction:
Improveload stabilityVSAvoidmechanism complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

Instead of providing separate displacement mechanisms for each of the four support arms, the invention merges the function into a single vertical shift means that moves the hook vertically. This single mechanism replaces multiple complex mechanisms, reducing device complexity and maintenance requirements while still achieving secure load stabilization through the hook's vertical positioning against the support arms.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The vertical shift means serves multiple functions: it positions the hook for coupling, secures the load during transport, and enables release when reversed. This multi-functional component replaces what would otherwise require multiple separate mechanisms, simplifying the overall device while maintaining load stability.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Reliability

If manual adjustment of support arms is required after load coupling, then the load can be stabilized, but the coupling process becomes time-consuming and reduces productivity

Engineering Contradiction:
Improveload stabilityVSAvoidcoupling speed
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The vertical shift means is designed to automatically position the hook in the appropriate position for each phase of operation. During coupling, the hook is self-positioned in the lowered position to facilitate easy load insertion. After coupling, the same mechanism automatically or readily shifts the hook to the raised position to secure the load, eliminating the need for manual adjustment and maintaining high coupling productivity.

Inventive Principle:
Principle #25Self-service

4Ease of manufacture

If geometric alignment precision is achieved through simple hook kinematics, then the device can be manufactured cost-effectively, but the alignment precision may be insufficient for loads with varying shapes and volumes

Engineering Contradiction:
Improvemanufacturing costVSAvoidalignment precision
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

Rather than relying solely on complex fixed kinematics to achieve alignment precision, the invention uses dynamic vertical positioning of the hook. The hook can be shifted vertically to accommodate different load positions and orientations, achieving precise alignment for various load shapes and volumes through movement rather than through complex manufactured geometries, thus maintaining ease of manufacture while improving alignment precision.

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

Enables precise geometric alignment, efficient stress transfer, reduces weight and production costs, and allows for quick and reliable coupling and release of loads, with automated and redundant actuation systems.

Implementation Method 1

The push rod can be actuated longitudinally to rotate the constraint means in the constraint position through the thrust obtained by the controlled heating of a device obtained with a shape memory material which extends when heated.

Methodology Applied
Scientific EffectShape memory material: Shape Memory Alloy

Implementation Method 2

a return spring

Methodology Applied
Scientific EffectSpring: Spring

Implementation Method 3

a screw and wedge lifting system

Methodology Applied
Scientific EffectScrew: Screw

Implementation Method 4

a screw and wedge lifting system

Methodology Applied
Scientific EffectWedge: Wedge

Data Source

PatentEP4477539B1Restrain and release mechanism for an externally airborne load with "single lug" interface
Publication Date: 2026.04.29 AEREA
  • EP4477539B1 patent drawingFigure 1
  • EP4477539B1 patent drawingFigure 2
  • EP4477539B1 patent drawingFigure 3

AI summary

Restrain and release mechanism for an externally airborne load (13) comprising a pair of support arms (8a,8b) for the load (13) and a hook (7) designed to be releasably coupled with a suspension ring (12) of the load (13). The hook (7) is rotatable between an opening position and a retention position of the suspension ring (12). Restrain and release mechanism comprises vertical shift means adapted to shift the hook (7) from the retention position to a blocking position in which the load (13) is pressed against the pair of support arms (8a,8b).