Segmented Brake Disc Assembly for Thermal Stress Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing brake disc assemblies for railway vehicles experience displacement and malfunction due to thermomechanical stresses caused by temperature changes, leading to potential braking system failures.

Innovation Solution

A brake disc assembly design featuring segments with angular offsets and hooks that allow for mechanical continuity and flexibility, along with ventilation fins for cooling, and a fixing device with sleeves and fasteners that accommodate expansion without applying excessive stress.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If screws are used to hold the wear crowns together, then the faces are secured axially around the hub, but thermomechanical stresses cause deformation and malfunction when temperature increases

Engineering Contradiction:
Improveholding strengthVSAvoidbraking system reliability
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The brake disc is divided into multiple segments (at least two distinct segments per face) that are arranged with angular offsets between corresponding segments of opposite faces. This segmentation allows each segment to independently accommodate thermal expansion, preventing the deformation and malfunction that occurs with conventional solid or screw-fastened designs.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention introduces asymmetry by offsetting the angular positions of corresponding segments between opposite faces. The radial edges of segments on one face do not align with the radial edges of corresponding segments on the opposite face, creating an asymmetric configuration that eliminates thermomechanical stress concentration and prevents deformation during temperature changes.

Inventive Principle:
Principle #4Asymmetry

2Ease of manufacture

If the brake disc is made as a solid structure, then manufacturing is simpler, but thermal expansion causes deformation and malfunction

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidbraking system reliability
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The brake disc is divided into multiple segments (at least two distinct segments per face) that are arranged with angular offsets between corresponding segments of opposite faces. This segmentation allows each segment to independently accommodate thermal expansion, preventing the deformation and malfunction that occurs with conventional solid or screw-fastened designs.

Inventive Principle:
Principle #1Segmentation

3Ease of operation

If segments are aligned radially between opposite faces, then assembly is easier, but thermomechanical stresses cause deformation when temperature changes

Engineering Contradiction:
Improveassembly easeVSAvoidbraking system reliability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The invention introduces asymmetry by offsetting the angular positions of corresponding segments between opposite faces. The radial edges of segments on one face do not align with the radial edges of corresponding segments on the opposite face, creating an asymmetric configuration that eliminates thermomechanical stress concentration and prevents deformation during temperature changes.

Inventive Principle:
Principle #4Asymmetry

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 effectively minimizes displacement and stress during temperature changes, ensuring the brake disc assembly remains stable and functional, reducing the risk of malfunctions and wear.

Implementation Method 1

the internal surface of each face has ventilation fins

Methodology Applied
Scientific EffectConvection: Convection

Implementation Method 2

the internal surface of each face has ventilation fins

Methodology Applied
Scientific EffectThermal radiation: Thermal Radiation

Implementation Method 3

when the temperature increases, the whole thing expands

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP3939854B1Disc assembly for a brake with segments
Publication Date: 2023.12.27 ALSTOM HOLDINGS SA
  • EP3939854B1 patent drawingFigure 1
  • EP3939854B1 patent drawingFigure 2
  • EP3939854B1 patent drawingFigure 3

AI summary

The invention relates to a brake disc assembly (10) comprising a central drive hub (12) and a wear disc having a first face and a second face (14, 16) held together axially around the hub (12). Each face (14, 16) has a respective internal surface (24, 26) and is formed of at least two distinct segments (32), each segment (32) extending between two radial edges (34, 36). The radial edges (34, 36) of the segments (32) of one face (14, 16) do not extend opposite the radial edges (34, 36) of the segments (32) of the other face (14, 16). Each face segment (32) is adapted to be fixed to a segment of the other face via at least one fastening member adapted to hold said faces (14, 16).