Semi-Trailer Train Articulation Layout for Tight Curve Passage

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Solution Overview

Problem

Existing articulated railway train configurations, such as the Jacob bogie, face challenges in navigating tight curves due to increased wheelbase and complexity, which also leads to higher costs and difficulties in motorization.

Innovation Solution

The proposed articulated railway train configuration features a chain of semi-trailer vehicles articulated to a main vehicle, with each semi-trailer vehicle equipped with a single support bogie and an inter-body joint allowing vertical pivot, enabling easier passage through curves while simplifying the body ends and reducing costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If Jacob bogies are used with four secondary suspensions, then the weight distribution and stability are improved, but the wheelbase increases reducing the ability to pass through tight curves

Engineering Contradiction:
Improveweight distributionVSAvoidwheelbase
Core Design Contradiction:
Stability of the object's compositionVSLength of moving object

Solution Approach 1:

The train is divided into a main vehicle and multiple semi-trailer vehicles, each with independent bogies. This segmentation allows each bogie to be optimized independently - using conventional shorter wheelbase bogies for curve negotiation while maintaining overall train stability through the articulated coupling system.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different parts of the train have different structural characteristics. The semi-trailer vehicles use conventional bogies with two secondary suspensions optimized for curve passage, while the main vehicle can have different configuration. The inter-body joints provide localized articulation to maintain stability without requiring increased wheelbase everywhere.

Inventive Principle:
Principle #3Local quality

2Stability of the object's composition

If Jacob bogies with doubled equipment are used, then the stability and support capability are improved, but the manufacturing cost increases

Engineering Contradiction:
Improvesupport capabilityVSAvoidmanufacturing cost
Core Design Contradiction:
Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

The patent uses conventional, standardized bogie designs that are simpler and cheaper to manufacture compared to custom Jacob bogies. These conventional bogies with two secondary suspensions are well-established components that reduce manufacturing costs while providing adequate support capability when used in the articulated semi-trailer configuration.

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

Solution Approach 2:

The articulated coupling system with inter-body joints provides multiple functions: it allows curve negotiation, distributes loads, and maintains stability without requiring each bogie to have doubled equipment. The same bogie design can be used across different semi-trailer vehicles, providing universality and reducing manufacturing complexity.

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

3Stability of the object's composition

If Jacob bogies with integrated equipment are used, then the support and stability are improved, but the motorization becomes more difficult

Engineering Contradiction:
ImprovesupportVSAvoidmotorization integration
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The train is segmented into independent semi-trailer vehicles that can be motorized separately. Motors can be installed on individual bogies or on the main vehicle without requiring complex integration across the entire train, as each unit operates semi-independently with its own propulsion capability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The articulated configuration with inter-body joints provides dynamic flexibility that accommodates motorization in various positions. The system can adapt to different motor placement configurations (on main vehicle, on semi-trailer vehicles, or on individual bogies) without requiring fixed integration schemes, simplifying the motorization process.

Inventive Principle:
Principle #15Dynamics

4Length of moving object

If conventional bogies with cantilevered suspension supports are used, then the curve passage ability is improved, but the body end complexity increases generating significant costs

Engineering Contradiction:
Improvecurve passage abilityVSAvoidbody end complexity
Core Design Contradiction:
Length of moving objectVSDevice complexity

Solution Approach 1:

Instead of cantilevering the suspension supports outward from the body end, the patent positions the inter-body joints and suspension supports inward, between the bogie pivot axis and the axle. This inverted arrangement reduces body end complexity while maintaining the ability to pass through curves, as the articulation point is located closer to the center of the vehicle rather than at the extreme end.

Inventive Principle:
Principle #13The other way round (Inversion)

Data Source

PatentEP4116165B1Chain of semi-trailer vehicles and associated articulated train
Publication Date: 2025.06.04 ALSTOM HOLDINGS SA
  • EP4116165B1 patent drawingFigure 1
  • EP4116165B1 patent drawingFigure 2
  • EP4116165B1 patent drawingFigure 3

AI summary

The present invention relates to a chain (12) of semi-trailer vehicles, intended to be articulated to a main vehicle (16), each semi-trailer vehicle comprising a body (20) and a single bogie supporting the body (20), referred to as a trailer bogie (22), the bodies (20) of the semi-trailer vehicles being articulated successively to one another from a first semi-trailer vehicle (14A) of the chain (12) by a separate inter-body articulation (50), each inter-body articulation (50) being carried by one end of each semi-trailer vehicle connected to a subsequent vehicle, each inter-body articulation (50) being articulated about a vertical pivot axis (ZA), each trailer bogie (22) of a body (20) carrying an inter-body articulation (50) being arranged longitudinally with respect to the body (20) such that the bogie axis (ZB) and the interconnection axis (ZA) are off-center.