Shackle Lock Sleeve Mechanism for Secure Pin Retention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional shackles lack user-friendly and safe mechanisms for securing the shackle pin to the shackle body, particularly in critical lifting operations where the pin must be connected above the load with an operator in close proximity, risking accidental disengagement.

Innovation Solution

A shackle lock system featuring a housing with a displaceable sleeve and locking bodies that engage with a peripheral groove on the shackle pin, allowing for passive locking and automatic engagement, optionally enhanced by springs or fluid pressure for secure retention, and featuring a peripheral locking groove on the shackle pin for additional safety.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional shackle pin is used with simple locking mechanisms (locking pin/nut), then the device complexity is low, but the reliability of preventing accidental disengagement is insufficient

Engineering Contradiction:
Improvereliability of preventing accidental disengagementVSAvoidcomplexity of locking mechanism
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The locking body automatically engages with the locking groove when the shackle pin is inserted, and the sleeve automatically returns to the locking position through spring bias after insertion. The system performs the locking function without requiring active manual intervention beyond the initial insertion motion, thereby improving reliability while maintaining operational simplicity.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The spring is pre-biased to push the locking body into engagement with the locking groove before any disengagement attempt occurs. This preliminary positioning ensures that the locking mechanism is always ready to secure the pin, preventing accidental disengagement without requiring complex active control systems.

Inventive Principle:
Principle #10Preliminary action

2Ease of operation

If a passive locking mechanism with automatic engagement is implemented, then the ease of operation is improved, but the device complexity increases due to additional components

Engineering Contradiction:
Improveease of securing shackle pinVSAvoidnumber of locking components
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The locking body and sleeve are integrated into a single functional unit where the locking body is positioned within the sleeve. This merging reduces the number of separate components while maintaining the passive locking functionality, as the locking body and sleeve work together as a coordinated assembly rather than independent elements.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The locking body is nested within the sleeve structure, with the locking body positioned inside the cylindrical sleeve. This nesting arrangement allows the locking mechanism to be compact and integrated, reducing overall complexity while enabling the sleeve to guide and protect the locking body during operation.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Reliability

If locking bodies are positioned to engage with peripheral locking grooves, then the reliability of locking is improved, but the manufacturing precision requirements increase

Engineering Contradiction:
Improvesecurity of pin lockingVSAvoidprecision of groove and locking body alignment
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The locking mechanism is segmented into distinct functional elements: the locking groove on the shackle pin, the locking body with engagement surface, and the guiding sleeve. This segmentation allows each component to be manufactured and assembled separately with standardized tolerances, reducing the cumulative precision requirements compared to a fully integrated mechanism.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The cylindrical sleeve acts as an intermediary element that guides the locking body into proper alignment with the locking groove during insertion. This mediator component compensates for minor misalignments and ensures reliable engagement without requiring extremely tight manufacturing tolerances on the locking groove and locking body interfaces.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 system provides a safer and simpler method for securing the shackle pin, reducing the risk of accidental disengagement and enhancing operational safety by ensuring the pin remains locked without requiring active manual intervention.

Implementation Method 1

The shackle lock may comprise a spring arranged to keep the sleeve in the locking position.

Methodology Applied
Scientific EffectSpring: Spring

Implementation Method 2

The shackle lock may be arranged to release the at least one locking body automatically when the shackle pin is being inserted into the shackle lock, in that the first end of the shackle pin comprises a cone arranged to force the at least one locking body outwards and thereby the sleeve backwards.

Methodology Applied
Scientific EffectAxial compression: Compression

Data Source

PatentEP4127511B1Schackle lock and shackle comprising said shackle lock
Publication Date: 2025.08.20 HYLESTAD SOLUTIONS AS
  • EP4127511B1 patent drawingFigure 1~2
  • EP4127511B1 patent drawingFigure 3~4
  • EP4127511B1 patent drawingFigure 5

AI summary

A shackle lock (300) for positioning on a shackle body (100), the shackle lock (300) comprising a housing (305', 305", 305"'), at least one locking body (310) and a sleeve (320, 320') which is displaceable in an axial direction of the housing (305', 305", 305'"). The housing (305', 305", 305'") is adapted for connection to the shackle body (100) and is arranged to house a first end (210, 210') of a shackle pin (200). The at least one locking body (310) is arranged to engage with a locking groove (230, 230') at the first end (210, 210') of the shackle pin (200). The sleeve (320, 320'), in a lock- ing position, is arranged to keep the at least one locking body (310) in the groove (230, 230'), and, in a releasing position, is arranged to release the at least one locking body (310) from the groove (230, 230'). A shackle (1) in which a shackle lock (300) is arranged on an outside of the first end (110) of the shackle body (100) is described as well.