Multilayer Braking Resistor Layout for Passive Vehicle Cooling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing braking resistor devices require large floor space for high braking power due to their single-layer arrangement, and active cooling methods reduce energy efficiency.

Innovation Solution

A multilayer stack arrangement of braking resistor elements with tubular casings, using passive airflow cooling through a stacked configuration with optimized spacing and airflow guidance to enhance thermal dissipation and reduce flow resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of stationary object

If a single-layer arrangement of braking resistor elements is used, then the overall height is reduced, but the floor space required increases linearly with braking power

Engineering Contradiction:
Improveoverall heightVSAvoidfloor space
Core Design Contradiction:
Length of stationary objectVSArea of stationary object

Solution Approach 1:

The patent transitions from a single-layer planar arrangement to a multi-layer stacked configuration, utilizing the vertical dimension to arrange braking resistor elements. This dimensional change allows the system to maintain compact floor space while accommodating high braking power through multiple stacked layers, effectively resolving the contradiction between floor space and braking power capacity.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent implements a nested stack arrangement where multiple layers of braking resistor elements are vertically stacked within a compact housing structure. Each layer is positioned above another, creating a nested configuration that maximizes the use of vertical space while maintaining a small footprint, thereby reducing floor space requirements while supporting high braking power.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Temperature

If active cooling components such as fans or additional heat exchangers are added, then thermal energy removal is improved, but energy efficiency is reduced

Engineering Contradiction:
Improvethermal energy removalVSAvoidenergy efficiency
Core Design Contradiction:
TemperatureVSUse of energy by moving object

Solution Approach 1:

The patent employs passive cooling where the housing structure itself serves as the heat dissipation system. The housing is designed with thermal conductivity to naturally conduct and dissipate heat from the braking resistor elements without requiring external active cooling components. This self-service approach maintains energy efficiency while effectively removing thermal energy through the housing's inherent thermal properties.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The housing structure performs multiple functions: it provides mechanical support for the stacked braking resistor elements, electrical insulation between layers, and thermal dissipation through its thermally conductive material. This multi-functionality eliminates the need for separate active cooling components, maintaining energy efficiency while achieving effective thermal energy removal.

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

3Temperature

If the surface area of the casing is increased to dissipate heat rapidly, then thermal energy removal is improved, but the device becomes less compact

Engineering Contradiction:
Improvethermal energy dissipation rateVSAvoiddevice compactness
Core Design Contradiction:
TemperatureVSVolume of stationary object

Solution Approach 1:

The patent utilizes the vertical dimension by stacking multiple layers of braking resistor elements within a compact horizontal footprint. This allows the system to achieve high thermal dissipation capacity through multiple layers without increasing the horizontal surface area of the casing, maintaining device compactness while improving thermal energy dissipation rate.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent creates asymmetric spacing between stacked layers, with larger clearance at the top and bottom layers and smaller clearance in intermediate layers. This asymmetric arrangement optimizes airflow patterns for heat dissipation while minimizing the overall vertical height, thereby achieving effective thermal dissipation without increasing device volume.

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 solution allows for compact, energy-efficient braking resistor devices with improved power-to-space ratio and reduced energy consumption by utilizing airflow for continuous thermal dissipation without active cooling components.

Implementation Method 1

A heat-conducting and electrically insulating material is arranged in the casing. Thanks to the thermal capacity of the heat-conducting, electrically insulating material, the thermal energy that briefly occurs during braking can be passively dissipated continuously during driving.

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

Braking resistors are used in vehicles to convert electrical energy recovered during braking into thermal energy.

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Implementation Method 3

Passive cooling refers to the dissipation of braking energy converted from electrical energy into thermal energy by braking resistor elements by means of airflow, convection, thermal radiation, and/or meteorologically induced air movement.

Methodology Applied
Scientific EffectConvection: Convection

Implementation Method 4

Passive cooling refers to the dissipation of braking energy converted from electrical energy into thermal energy by braking resistor elements by means of airflow, convection, thermal radiation, and/or meteorologically induced air movement.

Methodology Applied
Scientific EffectThermal radiation: Thermal Radiation

Data Source

PatentEP4277803B1Multilayer braking resistor device for a vehicle
Publication Date: 2025.06.25 SIEMENS MOBILITY GMBH
  • EP4277803B1 patent drawingFigure 1
  • EP4277803B1 patent drawingFigure 2
  • EP4277803B1 patent drawingFigure 3

AI summary

The invention relates to a braking resistance device (10) for a vehicle (12). The braking resistance device (10) has a plurality of braking resistance elements each having a tubular heat-conducting casing. A heat-conducting and electrically insulating material is provided in the casing. An electrical conductor is embedded in this material over a majority of the longitudinal extent of the casing. Furthermore, the braking resistance device (10) has a stacking arrangement which is designed to be passively cooled. The stacking arrangement has a plurality of layers which are arranged one above the other in a stacking direction and each comprise braking resistance elements of the plurality of braking resistance elements which are arranged substantially parallel to one another.