Plastic Rivet Coupling Element with Frusto-Conical Hole

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Metallic rivets used for fixing coupling elements like shoelace eyelets and buckles can oxidize, leading to deterioration and electrical conduction issues, while plastic alternatives suffer from protruding rivet portions that hinder functionality and aesthetics.

Innovation Solution

A coupling element with a frusto-conical through-hole and raised rings to improve adherence and grip of the rivet counterhead, allowing for a low-profile, aesthetically pleasing, and functionally enhanced coupling system using a plastic rivet.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a metallic rivet is used to fix the coupling element, then the rivet provides strong mechanical strength and grip, but the rivet undergoes oxidation leading to deterioration and electrical conduction issues

Engineering Contradiction:
Improvemechanical strength of rivetVSAvoidoxidation resistance and electrical insulation
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The invention changes the material parameter of the rivet from metal to plastic, fundamentally altering the chemical and electrical properties while maintaining mechanical functionality. The plastic material eliminates oxidation and provides electrical insulation, directly resolving the reliability issues while the mechanical design compensates for any strength differences

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention uses a composite structure where a plastic rivet combines mechanical fastening capability with electrical insulation properties. The plastic material serves multiple functions simultaneously: structural integrity, corrosion resistance, and electrical isolation, creating a multi-functional composite solution

Inventive Principle:
Principle #40Composite materials

2Reliability

If a plastic rivet is used to fix the coupling element, then the rivet provides electrical insulation and oxidation resistance, but the rivet creates a protruding portion that hinders functionality and aesthetics

Engineering Contradiction:
Improveoxidation resistance and electrical insulationVSAvoidfunctional usability and aesthetic appearance
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The invention addresses the protrusion issue by modifying the spatial geometry of the through-hole. By creating a frusto-conical portion within the through-hole, the counterhead is contained in a recessed dimension, eliminating the external protrusion while maintaining the internal grip structure. This dimensional reorganization solves both aesthetic and functional problems

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

Solution Approach 2:

The frusto-conical shape provides a curved, tapered surface that optimally distributes and contains the deformed plastic counterhead material. The conical geometry guides the material flow during deformation and creates a smooth transition that prevents sharp edges or protrusions, improving both appearance and functionality

Inventive Principle:
Principle #14Spheroidality (Curvature)

3Reliability

If a conventional cylindrical through-hole is used with a plastic rivet, then the rivet provides electrical insulation, but the rivet tip protrudes significantly from the coupling element after riveting

Engineering Contradiction:
Improveelectrical insulationVSAvoidprotrusion height of rivet counterhead
Core Design Contradiction:
ReliabilityVSLength of stationary object

Solution Approach 1:

The invention transitions from a cylindrical to a frusto-conical through-hole geometry, utilizing the tapered dimension to contain the counterhead material internally. This dimensional change allows the counterhead to be distributed along the conical surface rather than protruding externally, reducing the protrusion height to minimal or zero

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

4Reliability

If a plastic rivet is used with a conventional through-hole, then the rivet provides corrosion resistance, but the grip and tightness of the rivet are insufficient

Engineering Contradiction:
Improvecorrosion resistanceVSAvoidgrip and tightness of rivet
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The invention applies local quality by creating a frusto-conical portion with specific geometric properties optimized for material deformation and interlocking. The conical surface provides enhanced local grip through increased surface area and mechanical interlocking, while the plastic material maintains its corrosion resistance. The raised bodies further concentrate the grip force at specific locations

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The invention changes the geometric parameters of the through-hole from cylindrical to frusto-conical, fundamentally altering how the rivet material deforms and distributes during riveting. The conical geometry promotes more uniform material flow and creates superior mechanical interlocking, significantly improving grip and tightness while maintaining corrosion resistance

Inventive Principle:
Principle #35Parameter changes

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 ensures a secure, aesthetically improved, and non-obstructive coupling system by distributing the rivet counterhead effectively within the coupling element, enhancing tightness and reducing protrusion, thus addressing both functional and aesthetic concerns.

Implementation Method 1

the frusto-conical shape improves the adherence of the counterhead itself during the change of its conformation having a plastic behavior

Methodology Applied
Scientific EffectPlastic deformation: Plasticity

Data Source

PatentEP3585205B1Coupling element and coupling system comprising said coupling element
Publication Date: 2021.01.20 HAWAI ITAL
  • EP3585205B1 patent drawingFigure 1~3

AI summary

This is a coupling element, for example an eyelet (10) for laces, a button, a buckle, or other similar element, in which a through-hole is formed and is adapted to be traversed by a pin (14) of a rivet (12) in a plastic material. The through-hole of the coupling element is shaped in such a way that the counterhead (32) obtained by riveting the tip of the pin (14) is optimally attached to the coupling element itself.