Heat Exchanger Header Protrusions for Fin Retention and Drainage

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing heat exchanger designs for automotive air conditioning systems face issues with fin and tube height variations, thermal expansion, and condensate accumulation, leading to cosmetic defects, performance issues, and increased costs due to scrap and rework.

Innovation Solution

A heat exchanger design featuring a header with protrusions to retain end members and allow fluid drainage between the header and tubes, minimizing displacement and compression losses, and preventing condensate accumulation, which reduces thermal expansion effects and corrosion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a rail is placed under the corner laminations to prevent fin fallout, then fin retention is improved, but the device complexity increases and the rail may damage the slat it protects

Engineering Contradiction:
Improvefin retentionVSAvoidstructure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent removes the external rail component and extracts the retention function into the header itself through integrated protrusions. This eliminates the separate rail that could damage slats while maintaining fin retention through the header's built-in structural features.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The retention function previously performed by a separate rail is merged with the header structure. The protrusions are formed as integral parts of the header, combining the support and retention functions into a single component, thereby reducing device complexity and eliminating potential damage from separate rails.

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If a protective cage is placed on top of the condenser to prevent louver damage from curtains, then louver protection is improved, but the device complexity increases and the cage is subject to damage

Engineering Contradiction:
Improvelouver protectionVSAvoidstructure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent removes the external protective cage and extracts the protection function into the header structure itself. The integrated design eliminates the separate cage component that adds complexity and is susceptible to damage while providing continuous protection through the header's structural features.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The protective function previously performed by a separate cage is merged with the header. The header's integrated structure provides both support and protection without requiring an additional cage component, thereby reducing device complexity and eliminating the vulnerability of external protective structures.

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If the header and end member are tightly sealed to prevent fluid leakage, then sealing is improved, but condensate accumulation occurs leading to corrosion

Engineering Contradiction:
ImprovesealingVSAvoidcondensate accumulation
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies different qualities to different regions of the header-end member interface. The general interface maintains sealing through engagement features, while specific localized regions include drainage provisions that allow condensate to escape. This local differentiation enables both sealing and drainage functions to coexist without contradiction.

Inventive Principle:
Principle #3Local quality

4Ease of manufacture

If natural variation in fin and tube height is allowed, then manufacturing ease is improved, but compression effectiveness decreases leading to cosmetic defects

Engineering Contradiction:
Improvemanufacturing flexibilityVSAvoidcompression consistency
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent incorporates compensation features into the header and end member design that anticipate and cushion against height variations. The structural design includes built-in tolerance accommodation that maintains effective compression despite natural variations in fin and tube heights, eliminating the need for strict manufacturing controls while preventing cosmetic defects.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

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 effectively reduces fin fallout, tube slip, and louvre window issues, while maintaining compression and preventing corrosion, with minimal tooling and part cost increases, and allows for easy integration into existing manufacturing processes.

Implementation Method 1

drainage between the header and tubes, minimizing displacement and compression losses, and preventing condensate accumulation

Methodology Applied
Scientific EffectGravitational drainage: Gravitation

Implementation Method 2

thermal expansion in a brazing furnace can cause press joints to expand and lose effectiveness

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP1754946B1Heat exchanger
Publication Date: 2015.07.22 MAHLE BEHR GMBH & CO
  • EP1754946B1 patent drawingFigure 1
  • EP1754946B1 patent drawingFigure 2A~2B
  • EP1754946B1 patent drawingFigure 3

AI summary

A heat exchanger, and in particular a heat exchanger for a motor vehicle air conditioning system, has a manifold (10) with openings (20) for heat exchanger tubes (120, 125; 250, 255) and projections (30) at the ends of the manifold (10) for holding elements. The projections (30) are designed to maintain the position of the elements during the manufacture of the heat exchanger, so that no defects are introduced into the heat exchanger during production.