Rotatable Spring Ring Fastener for Low-Force Stud Retention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing fastening elements in the automobile industry face challenges in being easy to manufacture, requiring low mounting forces while maintaining high holding forces, and providing shock absorption to enhance stability and service life.

Innovation Solution

A fastening element with a housing featuring a recess and a rotatable spring ring seated in a radial slit, made of plastic materials like polyamide or polyoxymethylene, which includes spring fingers oriented at specific angles to secure the stud with low mounting forces and high holding forces, and designed to absorb shocks and prevent damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Force

If a conventional fastening element with a recess is used to secure a stud, then the fastening element can retain the stud, but it requires high mounting forces and cannot absorb shocks

Engineering Contradiction:
Improvemounting forceVSAvoidshock absorption capability
Core Design Contradiction:
ForceVSReliability

Solution Approach 1:

The spring ring is made rotatable within the housing, transforming the static fastening structure into a dynamic one. This rotational freedom allows the spring ring to adapt to shock loads and vibrations, enabling shock absorption while maintaining secure stud retention with reduced mounting forces

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The spring ring introduces elastic deformation capability to the fastening system. By changing the physical state from rigid to elastically flexible, the system can absorb shocks through controlled deformation while maintaining the necessary holding force on the stud

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If the housing is made of plastic material to simplify manufacturing, then ease of manufacture is improved, but strength and durability may be compromised

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidhousing strength
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The fastening element combines plastic housing material with a metal spring ring, creating a composite structure. The plastic housing provides ease of manufacture and vibration damping, while the metal spring ring contributes strength and elastic properties, together achieving both manufacturing simplicity and sufficient structural strength

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

Different parts of the fastening element use different materials optimized for their specific functions. The housing uses plastic for ease of manufacture and vibration absorption, while the spring ring uses metal for strength and elasticity, allowing each component to excel at its primary function

Inventive Principle:
Principle #3Local quality

3Duration of action of stationary object

If the spring ring is made rotatable in the slit to allow rotational motion, then service life is increased by decreasing damage risks, but device complexity increases

Engineering Contradiction:
Improveservice lifeVSAvoidfastening element complexity
Core Design Contradiction:
Duration of action of stationary objectVSDevice complexity

Solution Approach 1:

The rotatable spring ring adds only one degree of freedom to the system, creating a simple dynamic mechanism that significantly reduces damage risks from shocks and vibrations. This minimal increase in complexity yields substantial improvements in service life and reliability

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The spring ring's rotational capability changes the system from statically constrained to dynamically adaptive. This single parameter change (rotational freedom) enables the fastening element to accommodate misalignments and shock loads, extending service life without requiring complex multi-component mechanisms

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 provides a durable, lightweight fastening element that effectively secures components with low assembly forces, prevents unintended disassembly, and enhances vibration and noise damping, ensuring stability and extended service life, especially in vehicle applications.

Implementation Method 1

a spring ring seated in the slit, wherein the spring ring partially protrudes into the recess

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3348847B1Fastening element and system with a fastening element
Publication Date: 2021.08.25 NEWFREY LLC
  • EP3348847B1 patent drawingFigure 1~2
  • EP3348847B1 patent drawingFigure 3~4
  • EP3348847B1 patent drawingFigure 5~6

AI summary

System with a fastening element (10) and fastening element (10) comprising: a. a housing (12) having a top side and a bottom side, said housing (12) comprising a recess extending along a longitudinal axis and adapted to receive the shaft of a stud, and a slit extending radially from the recess, b. a spring ring seated in the slit, wherein the spring ring partially protrudes into the recess, wherein the sprig ring is seated rotatable in the slit, so that a rotational motion of the spring ring within the housing (12) is allowed, and the spring ring comprises a body and spring fingers wherein the body is an annular body defining a hole, and wherein the spring fingers protrude into the hole.