Non-Circular Protective Sleeve for Elastic Snap-Fit Mounting

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing technologies face challenges in mounting rigid cylindrical bushings, particularly those made of plastic or metal like aluminum, onto pump or valve housings due to their inherent material properties, which lack elasticity and shape memory, leading to permanent snap-fits or deformation.

Innovation Solution

A non-circular cross-section design for the cylindrical sleeve is implemented, featuring areas of larger and smaller diameters, allowing for elastic deformability, secured by a recessed shoulder, which provides elasticity through its configuration rather than material properties, enabling secure attachment to aluminum housings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a rigid cylindrical bushing made of plastic or metal is mounted onto an aluminum housing, then the structural integrity and quality perception are improved, but the mounting process becomes difficult due to lack of elasticity and shape memory in the materials

Engineering Contradiction:
Improvestructural integrityVSAvoidmounting ease
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The invention changes the geometric parameters of the bushing by transitioning from a circular cross-section to a non-circular cross-section with multiple flat faces and edges. This geometric transformation enables the rigid bushing to elastically deform during mounting and return to its original shape, achieving snap-fit functionality without requiring elastic materials. The parameter change resolves the contradiction by maintaining structural integrity while enabling easy mounting.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention introduces dynamic behavior to a previously static rigid component. The non-circular bushing can dynamically deform elastically during the mounting process and then return to its original configuration, creating a reversible snap-fit mechanism. This dynamic capability allows the rigid bushing to adapt to the housing during assembly while maintaining its structural strength.

Inventive Principle:
Principle #15Dynamics

2Ease of operation

If a plastic bushing with internal profiles is used to engage with the housing, then the bushing can deform elastically and return to shape for snap-fit mounting, but the use of plastic combined with metal reduces recycling value and quality perception

Engineering Contradiction:
Improvesnap-fit functionalityVSAvoidmaterial quality and recyclability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The invention changes the material parameter from plastic to metal (aluminum), improving quality perception and recyclability. Simultaneously, it changes the geometric parameter to a non-circular cross-section, which enables the metal bushing to exhibit elastic deformability during mounting. This dual parameter change resolves the contradiction by maintaining snap-fit functionality while using higher-quality, recyclable metal materials.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite structure by combining the non-circular geometric configuration with metal material properties. The resulting bushing exhibits both the elastic deformability needed for snap-fit mounting and the structural integrity and recyclability of metal. This composite approach resolves the contradiction between ease of operation and material reliability.

Inventive Principle:
Principle #40Composite materials

3Reliability

If an aluminum bushing is used to mount onto an aluminum housing, then material compatibility and recyclability are improved, but the bushing deforms permanently or becomes flattened during mounting due to aluminum's low elasticity

Engineering Contradiction:
Improvematerial compatibilityVSAvoidshape retention
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The invention changes the geometric parameter from circular to non-circular cross-section with multiple flat faces. This geometric transformation enables the aluminum bushing to elastically deform during mounting and return to its original shape, preventing permanent deformation. The parameter change resolves the contradiction by maintaining shape retention while using material-compatible aluminum for both the bushing and housing.

Inventive Principle:
Principle #35Parameter changes

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 design allows for removable and elastic attachment of aluminum bushings to aluminum housings, providing a secure fit without deformation, enhancing user experience and material compatibility.

Implementation Method 1

The flat faces and/or the edges exhibit elastic deformability

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP3928656B1Protective cover
Publication Date: 2025.11.19 RYLD
  • EP3928656B1 patent drawingFigure 1~2
  • EP3928656B1 patent drawingFigure 3~4
  • EP3928656B1 patent drawingFigure 5~8

AI summary

Protective cover (C) intended to be mounted on a circular cylindrical housing of a distribution element, such as a pump, the cover comprising a body (1), as well as a cylindrical sleeve (2) intended to engage around the circular cylindrical housing, characterized in that the cylindrical sleeve (2) has a non-circular cross-section defining areas of larger diameter (23) and areas of smaller diameter (21), and thus exhibiting elastic deformability, the areas of smaller diameter (21) delimiting an internally inscribed circular cylinder having a diameter equal to or slightly less than the external diameter of the circular cylindrical housing.