Thermoplastic Polyolefin Holding Element for Protective Hoods

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing protective hoods for motor vehicles require multiple work steps for production and may not securely attach at high speeds due to complex multi-part holding elements and additional sewing or welding processes.

Innovation Solution

A protective hood with holding elements made of thermoplastic polyolefin materials, featuring rounded edges and a one-piece design, which are sewn or ultrasonically welded to the hood, providing enhanced prestress and secure attachment without additional swelling or instability, and a polymer-coated non-woven fabric for impermeability and flexibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If holding elements are made from multiple layers of non-woven polyester fabric connected by sewing or welding, then the protective hood can be produced with conventional materials, but the production process requires multiple work steps including pressing, cutting, sewing or welding, and separate connection to the protective hood

Engineering Contradiction:
ImproveAvailability of conventional materialsVSAvoidNumber of production work steps
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The holding element is integrated directly into the protective hood as a single component made from thermoplastic material. The sealing edge and holding function are merged into one piece, eliminating the need for separate holding elements and their attachment processes. This reduces production steps while maintaining material availability advantages.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent uses thermoplastic material with specific properties (Shore hardness 40-70 D, density 0.90-1.0 g/cm³, elongation at break 400-700%) that combines the benefits of fabric flexibility with thermoplastic sealing capability. This composite material approach eliminates multiple production steps while maintaining ease of manufacture through conventional thermoplastic processing.

Inventive Principle:
Principle #40Composite materials

2Adaptability or versatility

If holding elements are separately connected to the protective hood through sewing or welding, then the holding elements can be produced independently, but additional work steps are required for connection

Engineering Contradiction:
ImproveIndependent production of holding elementsVSAvoidProduction efficiency
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The holding element is formed as an integral part of the protective hood from the same thermoplastic material. The sealing edge and holding functionality are combined in one component, eliminating separate production and attachment steps. This integration maintains adaptability while significantly improving productivity by reducing the number of operations required.

Inventive Principle:
Principle #5Merging (Combining)

3Strength

If the holding element has sharp edges to ensure firm attachment, then the prestress and holding force are maximized, but mechanical damage to the vehicle surface may occur

Engineering Contradiction:
ImproveHolding force of the holding elementVSAvoidMechanical damage to vehicle surface
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

The holding element features locally differentiated properties: the inner surface maintains high friction and firm attachment characteristics for strong holding force, while the outer edges are rounded to prevent mechanical damage to the vehicle surface. This local quality differentiation resolves the contradiction between holding strength and surface protection.

Inventive Principle:
Principle #3Local quality

4Ease of manufacture

If the protective hood uses a flat material design, then the production process is simplified, but air can penetrate at the edges during high-speed movement

Engineering Contradiction:
ImproveSimplicity of flat material productionVSAvoidSeal integrity at high speeds
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The sealing edge of the holding element is designed to deform dynamically under prestress to conform to the body edge contour. This dynamic adaptation ensures reliable sealing at high speeds while maintaining the simplicity of flat material production. The thermoplastic material's elasticity enables this dynamic sealing action.

Inventive Principle:
Principle #15Dynamics

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 reduces production steps, ensures secure attachment at high speeds, and maintains impermeability and flexibility, preventing air and moisture ingress while withstanding mechanical and chemical damage.

Implementation Method 1

The holding element is sewn or ultrasonically welded to the protective hood

Methodology Applied
Scientific EffectUltrasonic welding: Ultrasonic Vibration

Implementation Method 2

a holding element is provided which engages in a holding position under prestress on the body edge of the object to be protected

Methodology Applied
Scientific EffectPrestress: Tension

Implementation Method 3

a polymer-coated non-woven fabric for impermeability and flexibility

Methodology Applied
Scientific EffectPolymer coating: Coatings

Data Source

PatentEP1712393B1Protective cover, in particular for motor vehicles
Publication Date: 2013.09.18 VOLKSWAGEN AG
  • EP1712393B1 patent drawingFigure 1~2a
  • EP1712393B1 patent drawingFigure 3~4
  • EP1712393B1 patent drawingFigure 5

AI summary

The cover (1) has edges held at an object e.g. wheel, to be protected, where the cover is formed from a surface material. A retaining unit (11) is provided along one of the edges of the cover, which is arranged at a body edge (10) of the object. The retaining unit engages at the body edge in a retaining position under pre-stressing of the object, to connect itself directly with the cover. The retaining unit is formed from polyolefin.