Blind Rivet Screw Thread Length for Low-Mass Fastening

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing blind rivet screws are heavy due to excessive material usage, particularly in vehicle technology where weight is a critical factor, and may not provide sufficient length for tool engagement in thick materials, leading to potential failure in forming the closing head.

Innovation Solution

Designing a blind rivet screw with a threaded section that is maximally four threads plus 1 mm longer than the screw material thickness, incorporating a thin rivet sleeve with varying wall thicknesses, and a bolt contact wall with reduced thickness and potential cavity to minimize mass while ensuring sufficient load-bearing capacity and tool engagement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the threaded section is made longer to ensure sufficient tool engagement for forming the closing head in thick materials, then the reliability of tool engagement is improved, but the mass of the blind rivet screw increases

Engineering Contradiction:
Improvetool engagement reliabilityVSAvoidmass of blind rivet screw
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The patent applies parameter changes by precisely defining the threaded section length as a specific range (4-6 thread turns plus 1-3 mm) rather than using excessive material. This optimized parameter ensures sufficient tool engagement for forming the closing head while minimizing mass, directly resolving the contradiction between reliability and weight.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies local quality by providing different wall thicknesses in different regions of the rivet sleeve (thicker at the connection area, thinner at the deformation area). This localized material distribution ensures structural integrity where needed while reducing overall mass, addressing the contradiction between reliability and weight.

Inventive Principle:
Principle #3Local quality

2Weight of moving object

If material is removed from the connection area to reduce mass, then the weight of the blind rivet screw is reduced, but the load-bearing capacity may be compromised

Engineering Contradiction:
Improvemass of blind rivet screwVSAvoidload-bearing capacity
Core Design Contradiction:
Weight of moving objectVSStrength

Solution Approach 1:

The patent applies local quality by implementing varying wall thicknesses in the rivet sleeve, with a thicker wall at the connection area to maintain load-bearing capacity and a thinner wall at the deformation area to reduce mass. This localized differentiation resolves the contradiction between weight reduction and strength maintenance.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent applies segmentation by dividing the rivet sleeve into distinct regions with different material properties (thicker connection area, thinner deformation area). This segmentation allows each region to be optimized for its specific function, reducing overall mass while maintaining necessary strength.

Inventive Principle:
Principle #1Segmentation

3Weight of moving object

If the threaded section length is precisely optimized to minimize mass, then the weight of the blind rivet screw is reduced, but the risk of insufficient tool engagement in thick materials increases

Engineering Contradiction:
Improvemass of blind rivet screwVSAvoidadaptability to different material thicknesses
Core Design Contradiction:
Weight of moving objectVSAdaptability or versatility

Solution Approach 1:

The patent applies parameter changes by defining the threaded section length as a range (4-6 thread turns plus 1-3 mm) rather than a fixed value. This parameter optimization ensures sufficient tool engagement across different material thicknesses while minimizing mass, resolving the contradiction between weight reduction and adaptability.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies universality by designing the blind rivet screw with a threaded section that can accommodate various material thicknesses (from thin to thick materials). The optimized length range ensures the tool can engage and form the closing head reliably across different applications, achieving both mass reduction and versatility.

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

Data Source

PatentEP3514395B1Blind rivet screw
Publication Date: 2024.07.31 SFS GRP GERMANY GMBH
  • EP3514395B1 patent drawingFigure 1~4
  • EP3514395B1 patent drawingFigure 2~3c

AI summary

A blind rivet screw 2 is specified, comprising a rivet sleeve 4 with a setting head 5 and a deformation area for forming a locking head 7, and a bolt 8 with an external thread 9, which protrudes from the setting head 5 with a threaded section 10 and is connected to the rivet sleeve 4 in a connection area 11. The aim is to provide a blind rivet screw with low mass. For this purpose, the threaded section 10, when the locking head 7 is formed, is a maximum of four threads plus 1 mm longer than the target fastening area A of the blind rivet screw 2, and the threaded section 10, when the rivet sleeve 4 is undeformed, protrudes at least four threads beyond the rivet sleeve 4.