Self-steering Radial Bogie Links with Variable Stiffness Bushings

Solution Overview

Problem

Traditional radial bogies for railroad vehicles require steering linkage mechanisms, which increase weight and cost, and do not efficiently manage radial adjustment for curve negotiation.

Innovation Solution

A self-steering system for radial bogies using links with varying stiffness bushings to connect leading and trailing wheelsets to the bogie frame, providing radial adjustment without the need for a steering linkage mechanism, and incorporating dampers for enhanced steering efficiency and stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a steering linkage mechanism is used in traditional radial bogies, then the radial adjustment for curve negotiation is achieved, but the weight and cost increase significantly

Engineering Contradiction:

Improvecurve negotiation capabilityVSAvoidbogie weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The patent removes the traditional steering linkage mechanism (inter-axle link or guide rod) from the radial bogie system. Instead of using a mechanical linkage to couple the rotation of steering beams, the invention employs a simplified arrangement where wheelsets are directly connected to the bogie frame through resilient elements, extracting the unnecessary steering linkage components while maintaining radial adjustment functionality.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The radial adjustment function is achieved through the self-steering capability of the wheelsets themselves, guided by the resilient connections to the bogie frame. The system uses the natural response of the wheelsets to lateral forces during curve negotiation, eliminating the need for an active steering linkage mechanism to impose radial adjustment.

Inventive Principle:

Principle #25Self-service

2Reliability

If a steering linkage mechanism is used in traditional radial bogies, then the radial adjustment for curve negotiation is achieved, but the cost increases significantly

Engineering Contradiction:

Improvecurve negotiation capabilityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent removes the traditional steering linkage mechanism (inter-axle link or guide rod) from the radial bogie system. Instead of using a mechanical linkage to couple the rotation of steering beams, the invention employs a simplified arrangement where wheelsets are directly connected to the bogie frame through resilient elements, extracting the unnecessary steering linkage components while maintaining radial adjustment functionality.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The radial adjustment function is achieved through the self-steering capability of the wheelsets themselves, guided by the resilient connections to the bogie frame. The system uses the natural response of the wheelsets to lateral forces during curve negotiation, eliminating the need for an active steering linkage mechanism to impose radial adjustment.

Inventive Principle:

Principle #25Self-service

3Device complexity

If traditional radial bogie arrangements are used, then structural simplicity is maintained, but radial adjustment efficiency during turns is reduced

Engineering Contradiction:

Improvebogie structureVSAvoidradial adjustment efficiency

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent changes the mechanical parameters of the connection between wheelsets and the bogie frame by introducing resilient elements with specific stiffness characteristics. These resilient connections allow controlled movement and radial adjustment of wheelsets during curve negotiation, optimizing the balance between structural simplicity and adjustment efficiency through carefully selected stiffness parameters.

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 system allows for efficient radial adjustment of wheelsets during turns, reducing friction and wear, while minimizing weight and cost by eliminating the need for steering linkages and improving stability through progressive stiffness and damping.

Implementation Method 1

The larger degree of movement is generally achieved by using a relatively soft or resilient bushing at the other end of the link

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

The damper provides greater steering efficiency and high stability

Methodology Applied

Scientific EffectViscous damping: Viscous Damping

Data Source

PatentUS8701564B2Self-steering radial bogie

Publication Date: 2014.04.22 PROGRESS RAIL LOCOMOTIVE INC

AI summary

A self-steering system for a radial bogie of a railroad vehicle is provided. The self-steering system includes a plurality of links which connect the leading and trailing wheelsets to the bogie frame. Each of the links is adapted to provide a smaller degree of movement between the link and the wheelset at one end and a larger degree of movement between the link and the bogie frame at the other end.