Pleated Filter Medium Sealing Without Adhesive End Caps

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for producing filter media require complex adhesive bonds and end caps, increasing manufacturing effort and cost, while also posing environmental challenges due to adhesive use.

Innovation Solution

A method involving the application of a weldable plastic strip as a sealing agent to a fluid-permeable media sheet, which is then welded to create a solid bond, forming filter folds without the need for end caps, and a filter device that allows easy replacement of the filter element.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If adhesive bonds and end caps are used to produce filter media, then the filter element can be assembled with structural support, but the manufacturing effort and cost increase

Engineering Contradiction:
Improvestructural integrity of filter elementVSAvoidmanufacturing effort
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The invention extracts and eliminates the end caps from the filter element structure. Instead of using traditional end caps that require adhesive bonding, the filter medium is folded back onto itself to form the end seals, completely removing the need for separate end cap components and their associated assembly operations.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention merges the filtering function and sealing function into a single integrated structure. The filter medium itself is folded back to simultaneously provide filtration and create the end seals, combining multiple functions that were previously performed by separate components (filter medium plus end caps).

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If adhesive bonds are used to connect end caps and filter medium, then the assembly is held together, but environmental challenges arise from adhesive materials

Engineering Contradiction:
Improvebond strengthVSAvoidenvironmental impact
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The invention creates a disposable filter element where the entire assembly including seals can be discarded as a single unit. The folded-back filter medium forms seals that are sufficient for the service life of the filter, eliminating the need for permanent adhesives and enabling easier disposal and recycling.

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

3Reliability

If end caps are used in the filter element design, then the filter medium is secured, but the device complexity increases

Engineering Contradiction:
Improvesecuring of filter mediumVSAvoidnumber of components
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention removes the end caps from the component list entirely. The filter medium is folded back onto itself to create the end seals, eliminating the need for separate end cap components and simplifying the overall device structure.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The filter medium serves multiple functions: it provides filtration in the extended section and creates end seals when folded back. This multi-functionality eliminates the need for dedicated sealing components, reducing the total number of parts in the system.

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

4Reliability

If adhesive bonds are used to attach filter medium to end caps, then the connection is formed, but manufacturing cost increases

Engineering Contradiction:
Improveconnection strengthVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The invention extracts the adhesive bonding process from the manufacturing sequence. By folding the filter medium back onto itself to form seals, the need for adhesive application, curing, and associated quality control steps is completely eliminated, reducing manufacturing cost and complexity.

Inventive Principle:
Principle #2Taking out (Extraction)

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

Enables cost-effective and environmentally friendly production of filter elements with reliable seals, allowing easy replacement and disposal without adhesives, thus reducing manufacturing complexity and environmental impact.

Implementation Method 1

a strip-shaped sealant (16, 28) consisting at least partially of a weldable plastic material is applied to the media web (14) and is welded on by means of a welding process (12) to create the firm bond

Methodology Applied
Scientific EffectWelding: Welding

Data Source

PatentEP4271499B1Process of forming a filtering medium
Publication Date: 2026.04.22 HYDAC FILTERTECHNIK GMBH
  • EP4271499B1 patent drawingFigure 1~3
  • EP4271499B1 patent drawingFigure 4~5
  • EP4271499B1 patent drawingFigure 6~7

AI summary

The invention relates to a method for forming a filter medium, which is suitable for filtering fluids, for a filter element, said method having at least the following steps: - applying at least one self-contained sealant (16, 28) onto a fluid-permeable media web (14) in a specifiable direction (26), - producing a solid composite at least between parts of the sealant (16, 28) and the media web (14), - pleating the composite, thereby forming individual filter folds, - producing a hollow body in that the two lateral edges of the media web (14) which lie opposite each other so as to adjoin each other and which run transversely to the specified direction are connected together such that in order to - obtain at least one seal region on the media web (14), the respective sealant (16, 28) is arranged on the inner face of the hollow body, a seal is produced for each filter fold, and an end-face seal of the media web (14) is produced.