Air Filter Element Alignment Contours for Flow Resistance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing air filter elements for internal combustion engines exhibit inhomogeneous flow resistance due to the attachment of end pleats, which can affect the accuracy of air mass sensors and require recalibration upon filter replacement, increasing maintenance costs and effort.

Innovation Solution

The air filter element features axial end disks with protruding alignment contours that interact with complementary counter-contours in the filter housing, ensuring consistent rotational positioning and reducing the influence of flow resistance variations, allowing for precise alignment and potentially eliminating the need for recalibration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If end pleats are attached to each other to form the filter body, then the filter element can be assembled, but the flow resistance becomes inhomogeneous in the circumferential direction

Engineering Contradiction:
Improvefilter element assemblyVSAvoidflow resistance distribution
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent applies asymmetry by providing alignment contours with specific geometric features (protrusions, recesses, cam profiles) that create a predetermined non-rotational symmetric position of the filter element in the filter housing. This asymmetric positioning ensures that the end pleats, which cause inhomogeneous flow resistance, are always oriented in the same circumferential position relative to the housing, thereby standardizing the flow pattern downstream despite the inherent asymmetry in the filter element construction

Inventive Principle:
Principle #4Asymmetry

2Ease of repair

If the filter element is replaced during inspection, then maintenance is performed, but recalibration of the air mass sensor is necessary due to different rotational positions

Engineering Contradiction:
Improvefilter element replacementVSAvoidrecalibration time
Core Design Contradiction:
Ease of repairVSLoss of time

Solution Approach 1:

The patent applies preliminary action by pre-configuring alignment contours on the filter element and corresponding alignment counter-contours in the filter housing that automatically guide the filter element into a predetermined rotational position during installation. This preliminary alignment mechanism ensures that regardless of which filter element is installed, it will always assume the same angular orientation, thereby eliminating the need for recalibration of downstream sensors such as the air mass sensor

Inventive Principle:
Principle #10Preliminary action

3Volume of moving object

If the air mass sensor is positioned close to the filter element, then space is optimized, but the measurement accuracy is affected by the rotational position of the filter element

Engineering Contradiction:
Improvesensor placement flexibilityVSAvoidair mass measurement
Core Design Contradiction:
Volume of moving objectVSMeasurement precision

Solution Approach 1:

The patent applies asymmetry through alignment contours that create a fixed, non-rotational symmetric relationship between the filter element and the filter housing. By ensuring the filter element can only be installed in one specific angular position, the asymmetric flow pattern created by the end pleats is consistently oriented relative to the air mass sensor, allowing the sensor to be positioned close to the filter element while maintaining accurate and repeatable measurements

Inventive Principle:
Principle #4Asymmetry

Data Source

PatentEP2509699B1Filter element and air filter
Publication Date: 2016.03.02 MAHLE INT GMBH
  • EP2509699B1 patent drawingFigure 1
  • EP2509699B1 patent drawingFigure 2~3

AI summary

The invention relates to a filter element (3), in particular for an air filter (1) of a fresh air system of an internal combustion engine, having an annular filter body (4) made of a folded filter material (5), having at least one end disc (14, 15) fastened to the filter material at an axial end face (12, 13) of the filter body (4), wherein two end folds (10) of the filter material (5) adjacent in the circumferential direction (9) are fastened to each other. Reliable functioning of the fresh air system can be achieved if at least one such end disc (15) comprises at least one alignment contour (16) protruding radially and/or axially from said end disc (15).