Plastic Joint Securing Device with Snap-In Latching Section

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing joint locks for securing levers relative to a pivot pin are either complex to assemble or prone to failure due to axial forces and deformation, with known solutions requiring additional tools or large overhangs for nut locks and complex assembly for snap rings.

Innovation Solution

A joint securing device with a latching section that can be easily attached to one lever without tools, using a snap-in connection and made from plastic for elasticity and robustness, providing a friction fit or form fit to secure levers against axial movement without the need for threads or grooves on the pivot pin.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a nut lock is used to secure the lever on the pivot pin, then assembly is very easy, but the nut can be twisted off after long period of use and requires large overhang of the hinge pin

Engineering Contradiction:
Improveassembly easeVSAvoidsecuring reliability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The securing device is divided into a bracket section with two bracket legs that secure the lever, and a separate connecting section that attaches to the lever. This segmentation allows the securing function and connection function to be independent, enabling easy attachment while maintaining reliable securing.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The connecting section acts as an intermediary between the bracket section and the lever. It provides a snap-in connection that is easy to assemble while transferring the securing force reliably to the lever without requiring threads or grooves on the pivot pin.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If snap rings are used to secure the joint pin, then securing is reliable, but assembly is comparatively complex requiring additional tools to widen the retaining rings

Engineering Contradiction:
Improvesecuring reliabilityVSAvoidassembly ease
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The connecting section is designed to be self-expanding through elastic deformation. When pressed onto the lever, it automatically widens and then snaps into place without requiring external tools to widen it, making assembly as easy as pushing while maintaining reliable securing.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The connecting section utilizes elastic deformation as a temporary parameter change during assembly. The material is elastically deformed to a larger diameter for easy attachment, then returns to its original smaller diameter to create the securing friction fit, enabling tool-free assembly with reliable retention.

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If the connecting section is designed as a latching section with snap-in connection, then assembly is very easy without tools, but requires elastic deformation and widening of the latching section

Engineering Contradiction:
Improveassembly easeVSAvoidstructural complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The connecting section is designed as a flexible elastic structure that can be deformed and widened temporarily during assembly. This flexible design allows simple snap-in attachment without tools, while the elasticity provides the necessary structural complexity only when needed for assembly.

Inventive Principle:
Principle #30Flexible shells and thin films

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 solution allows for easy installation and reliable axial security of levers, enabling easy disassembly and variable use, while the plastic material simplifies production and ensures robustness, preventing lever slippage off the pivot pin.

Implementation Method 1

By applying a specific force to the latching section, it can be elastically deformed and widened, so that the latching section can be pushed over one of the levers or onto one of the levers. If the force is removed again, the latching section resumes its original shape due to the elasticity of the material and leads to a latching connection with one of the levers.

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

The joint securing device and the lever can then be connected to one another with a friction fit or with a form fit.

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3636863B1Securing device for a joint
Publication Date: 2022.04.13 EMKA BESCHLAGTAILE GMBH & CO KG
  • EP3636863B1 patent drawingFigure 1
  • EP3636863B1 patent drawingFigure 2a~3
  • EP3636863B1 patent drawingFigure 4~5

AI summary

The invention relates to a joint locking device (1) for securing two levers (2, 3) rotatable relative to each other about a joint axis (G) and connected via a joint bolt (7), which has a bracket section (4) for axially fixing the two levers (2, 3) on the joint bolt (7) and a connecting section (5) for connecting to one of the two levers (2, 3).