Composite Elastomer-Metal Bushing for Lower Vehicle Bearing Weight

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing elastomer-metal bushings used in vehicles are heavy, leading to reduced energy efficiency, particularly in large applications like commercial vehicles and railway bogies, where they contribute to increased weight and higher manufacturing costs.

Innovation Solution

The elastomer-metal bushing is designed with a stable inner part consisting of a combination of metal and plastic, where the inner flat steel part is surrounded by a plastic body, reducing overall weight and eliminating the need for machining and mechanical notches, allowing for a more compact, cost-effective, and stress-reduced design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the inner part is made entirely of metal to ensure strength and stability, then the load-bearing capability is improved, but the weight increases significantly

Engineering Contradiction:
Improveload-bearing capabilityVSAvoidweight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The inner part is constructed as a composite structure combining a metal core (for strength and load-bearing) with a plastic outer layer (for weight reduction and corrosion resistance). This composite design allows the component to achieve the required mechanical strength while significantly reducing the overall weight compared to a fully metallic construction.

Inventive Principle:
Principle #40Composite materials

2Reliability

If conventional metal machining is used to create connecting jaws, then the structural integrity is maintained, but manufacturing costs and complexity increase

Engineering Contradiction:
Improvestructural integrityVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The invention replaces traditional mechanical machining processes with injection molding technology. The connecting jaws are formed directly during the injection molding process through integrated cavity design, eliminating the need for subsequent machining operations, reducing manufacturing steps, and lowering production costs while maintaining structural integrity.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Ease of operation

If mechanical notches are created in the metal part, then connection features are achieved, but stress concentration points are created reducing fatigue strength

Engineering Contradiction:
Improveconnection capabilityVSAvoidfatigue strength
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The invention changes the geometric parameters of the connecting jaws by designing them with rounded transitions and optimized thickness variations directly in the injection molding process. This eliminates sharp notches and stress concentration points while maintaining the necessary connection capability, thereby improving fatigue strength.

Inventive Principle:
Principle #35Parameter changes

4Reliability

If high-strength steel is used to ensure fatigue resistance, then the durability is improved, but the weight and material cost increase

Engineering Contradiction:
ImprovedurabilityVSAvoidweight
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The composite structure allows the use of a metal core that provides the necessary strength and fatigue resistance, while the plastic outer layer contributes to weight reduction. This enables the use of lower-grade, lighter metals compared to fully metallic designs, achieving durability requirements with reduced weight and material cost.

Inventive Principle:
Principle #40Composite materials

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

This design achieves a significant weight reduction of approximately 400 grams per bushing, enhancing energy efficiency and reducing production costs while maintaining load-bearing capabilities, and allows for the use of lower-strength, more cost-effective steel materials.

Implementation Method 1

An elastomer layer is firmly vulcanized between the inner and outer parts

Methodology Applied
Scientific EffectVulcanization: Chemical Bonding

Data Source

PatentEP4253789A1Elastomeric metal bushing, particularly for vehicles
Publication Date: 2023.10.04 JORN GMBH
  • EP4253789A1 patent drawingFigure 1~2
  • EP4253789A1 patent drawingFigure 3~4
  • EP4253789A1 patent drawingFigure 5~6

AI summary

The invention relates to an elastomer-metal bushing (1), particularly for vehicles, comprising a stable inner part (2) with a circular cylindrical cross-section for attachment to a first bearing part with an outer tube (16), and a vulcanized elastomer layer (18) between the inner part (2) and the outer tube (16). The elastomer-metal bushing (1), in its fully assembled state, is pressed into a receiving eye for connection or as a component of a second bearing part, acting as a spherical bearing with a reduction in the diameter of the outer tube (16) and the creation of a preload in the elastomer layer (18). According to the invention, the stable, circular cylindrical inner part (2) consists of an inner flat steel part (3) surrounded by a plastic body (4) with a circular cylindrical outer shape.