Thermoplastic Elastomer Seal with Variable Pitch Helix

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing seals with spiralized profile cords have large axial dimensions, do not fully fill their installation space, and are difficult and costly to replace, as they require dismantling and reassembly with joining processes.

Innovation Solution

A seal with a spiralized profile cord made of thermoplastic elastomer, forming a rectangular coil package with snap connections for secure assembly and easy replacement, allowing for compact dimensions and efficient use of space without the need for destructive dismantling or joining processes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the seal uses a spirally wound profile cord with constant pitch helixes, then the seal structure is simple and easy to manufacture, but the axial dimensions become large and the installation space is not fully utilized

Engineering Contradiction:
Improveease of manufactureVSAvoidaxial dimensions
Core Design Contradiction:
Ease of manufactureVSLength of moving object

Solution Approach 1:

The patent applies the dynamics principle by transitioning from a constant pitch helix structure to a variable pitch helix structure. The helix pitch varies along the axial direction, being smaller at the ends and larger in the middle section, which allows the seal to adapt its shape dynamically to fill the installation space completely while maintaining manufacturability through a single extrusion process.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies parameter changes by modifying the geometric parameter of the helix pitch along the axial direction. The pitch parameter is not constant but varies continuously, creating an optimized three-dimensional shape that reduces axial dimensions while ensuring complete filling of the installation space. This is achieved through controlled variation of the winding parameters during manufacturing.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the seal is designed as a self-contained closed sealing ring, then the seal provides complete sealing, but the replacement requires time-consuming dismantling and joining processes

Engineering Contradiction:
Improvesealing completenessVSAvoidease of replacement
Core Design Contradiction:
ReliabilityVSEase of repair

Solution Approach 1:

The patent applies segmentation by dividing the closed sealing ring into two separate semi-rings that can be independently installed. Each semi-ring can be placed into the installation space separately and then connected through complementary connection elements, eliminating the need for complex dismantling and joining processes while maintaining complete sealing through the connection interface between the two semi-rings.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies preliminary action by pre-forming the connection elements (such as hooks, lugs, or interlocking features) on the semi-rings during manufacturing. These connection elements are prepared in advance to enable quick and tool-free assembly, allowing the seal to be installed in a single operation without requiring subsequent joining processes like welding, bonding, or mechanical fastening.

Inventive Principle:
Principle #10Preliminary action

3Stability of the object's composition

If the seal requires joining processes for assembly, then the seal structure is complete and stable, but the manufacturing cost and time increase

Engineering Contradiction:
Improvestructural stabilityVSAvoidmanufacturing efficiency
Core Design Contradiction:
Stability of the object's compositionVSProductivity

Solution Approach 1:

The patent applies self-service by designing self-contained connection elements that automatically secure the semi-rings together upon assembly. The connection mechanism (such as snap-fit hooks, interlocking lugs, or elastic retention features) performs the joining function automatically without requiring external tools, operators, or additional manufacturing steps, thereby eliminating joining processes entirely while maintaining structural stability.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent applies the principle of using simple, inexpensive connection elements that can be integrated directly into the seal structure during extrusion. These connection features are formed as integral parts of the semi-rings using the same thermoplastic elastomer material, requiring no separate components or assembly operations, thus eliminating joining costs and improving manufacturing efficiency.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

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 seal achieves compact axial dimensions, complete installation space filling, and easy replacement, ensuring reliable sealing and reduced maintenance costs, particularly suitable for large bearings in wind power drives.

Implementation Method 1

made of at least one thermoplastic elastomer material

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

with snap connections for secure assembly and easy replacement

Methodology Applied
Scientific EffectMechanical Fastener: Mechanical Fastener

Data Source

PatentEP4242497B1Seal and method for the production thereof
Publication Date: 2024.12.18 CARL FREUDENBERG KG
  • EP4242497B1 patent drawingFigure 1
  • EP4242497B1 patent drawingFigure 2

AI summary

Seal comprising a spiral profile cord (1) with a retaining part (2) and with at least one sealing lip (3) arranged opposite each other in a radial direction (4), wherein the profile cord (1) comprises helixes (6) arranged adjacent to each other and intersecting in an axial direction (5) and has end faces (7, 8) open on both sides.