Ventilated Brake Disc Channels for Uniform Thermal Relief

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing brake discs suffer from inadequate cooling and ventilation, leading to thermal expansion and degradation, which causes damage and affects the performance of the braking system due to uneven heat distribution and increased temperature gradients.

Innovation Solution

A brake disc assembly with radial protrusions and strategically placed through-holes and fasteners that maximize airflow across the disc, directing it radially outward to effectively ventilate heat and reduce thermal stress, allowing for improved cooling and reduced wear-based damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If traditional brake disc design is used with minimal fixation points, then manufacturing is simpler, but cooling efficiency is insufficient leading to thermal expansion and degradation

Engineering Contradiction:
Improvecooling efficiencyVSAvoidstructural complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The brake disc is divided into multiple segments that are spaced apart by gaps, allowing each segment to expand independently during thermal cycles. The segments are connected by joining elements that permit relative movement, enabling thermal expansion while maintaining structural integrity. This segmentation resolves the contradiction by providing effective cooling pathways through the gaps while distributing thermal stress across multiple independent components.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different regions of the brake disc are given different properties: the segments have friction surfaces for braking, gaps for cooling airflow, and joining elements for structural connection. The inner surface includes protrusions that direct airflow radially outward, creating localized cooling zones where heat is most intense. This local differentiation optimizes cooling efficiency without requiring complete structural redesign.

Inventive Principle:
Principle #3Local quality

2Temperature

If cooling airflow is increased to counteract heat, then thermal degradation is reduced, but temperature gradients worsen causing fissures and cracks

Engineering Contradiction:
Improvethermal degradation resistanceVSAvoidtemperature uniformity
Core Design Contradiction:
TemperatureVSStability of the object's composition

Solution Approach 1:

The segmented structure with gaps between segments allows cooling airflow to pass through multiple pathways simultaneously, distributing the cooling effect more uniformly across the disc. Each segment experiences similar cooling conditions, preventing large temperature gradients between different regions. The joining elements ensure that segments remain at comparable temperatures, reducing differential thermal expansion and preventing fissures.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The joining elements allow the segments to move dynamically in response to thermal expansion and contraction. As temperature changes, segments can adjust their positions relative to each other, maintaining optimal spacing for airflow while accommodating thermal dimensional changes. This dynamic adjustment prevents stress concentration and uniform temperature distribution is maintained across all segments.

Inventive Principle:
Principle #15Dynamics

3Temperature

If heat is transferred to the shaft for cooling, then brake disc temperature is reduced, but oxidation occurs on the shaft and wheel requiring more frequent replacement

Engineering Contradiction:
Improvebrake disc temperature controlVSAvoidshaft and wheel durability
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The cooling function is extracted from the shaft and wheel and assigned to the brake disc segments themselves. The gaps between segments and the radial airflow channels create dedicated cooling pathways that dissipate heat directly from the friction surfaces and through the segment structure. This prevents heat transfer to the shaft and wheel, eliminating the oxidation problem while maintaining effective temperature control of the brake disc.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The gaps between segments and the airflow channels act as intermediary cooling pathways that intercept heat before it can transfer to the shaft. Cool air flows through these intermediary spaces, absorbing heat from the segment surfaces and carrying it away from the assembly. This intermediary cooling mechanism protects the shaft and wheel from thermal exposure and oxidation.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Ease of repair

If segmented brake disc is used to permit thermal expansion, then maintenance is simplified, but manufacturing precision is reduced due to gaps and joining elements

Engineering Contradiction:
Improvemaintenance accessibilityVSAvoidsegment alignment precision
Core Design Contradiction:
Ease of repairVSManufacturing precision

Solution Approach 1:

The brake disc is segmented into identical or similar modules that can be manufactured separately with standard tolerances and then assembled. The joining elements are designed with features that ensure proper alignment during assembly, such as tapered surfaces, keyed connections, or self-centering mechanisms. This modular segmentation enables individual segment replacement during maintenance while maintaining sufficient manufacturing precision through standardized connection interfaces.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The joining elements serve multiple functions: they connect segments structurally, allow for thermal expansion movement, ensure proper alignment, and provide pathways for cooling airflow. This multi-functionality reduces the number of separate components needed and simplifies the overall assembly process. The universal design of joining elements allows for easy replacement and maintenance while maintaining precise alignment through integrated alignment features.

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

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 solution enhances cooling efficiency, reduces damage from thermal stress, and operates more quietly than traditional systems by ensuring uniform airflow and minimizing the number of fixation points for improved ventilation and reduced thermal expansion.

Implementation Method 1

an annular brake disc with a ventilating structure for directing airflow across at least a portion of the disc to transfer heat therefrom

Methodology Applied
Scientific EffectForced Convection: Forced Convection

Implementation Method 2

The heat may cause thermal expansion of portions of the brake assembly and may cause the brake assembly to deform or degrade following prolonged use

Methodology Applied
Scientific EffectThermal Expansion: Thermal Expansion

Implementation Method 3

a considerable amount of the heat created on the contact surface of the brake element is transferred to the shaft on which the brake disc is mounted

Methodology Applied
Scientific EffectThermal Conduction: Conduction (thermal)

Data Source

PatentEP4112965B1Ventilated brake disc
Publication Date: 2023.12.20 WESTINGHOUSE AIR BRAKE TECH CORP
  • EP4112965B1 patent drawingFigure 1
  • EP4112965B1 patent drawingFigure 2
  • EP4112965B1 patent drawingFigure 3

AI summary

A friction ring configured to be fixed to a hub at one or more fixation points is provided. The friction ring includes a ring shaped body; an outer surface configured to be contacted by a brake mechanism; an inner surface configured to contact a portion of a hub or axle to impart a braking force thereto; at least one through-hole for receiving a fastener for fixing the friction ring to the hub or axle; and at least two protrusions extending from the inner surface of the friction ring forming a channel. A cross-sectional area of an inflow portion of the channel is smaller than a cross-sectional area of an outflow portion of the channel. A brake assembly including a hub and the fixation ring is also provided.