In-Wheel Motor Cooling Jacket for Leak-Safe Electronics Access

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Solution Overview

Problem

Existing in-wheel motors require partial disassembly for maintenance and inspection, which involves disconnecting and reconnecting coolant, risking spills and complicating access to control electronics.

Innovation Solution

An in-wheel motor design with a hollow stator body and a connector member allowing coolant channels to be accessed without disassembly, featuring parallel and series-connected cooling channels for improved cooling efficiency and easy maintenance, with an open end for inserting/removing control electronics without disconnecting coolant supply.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If the stator is fully assembled with coolant channels, then cooling efficiency is improved, but maintenance and inspection require disassembly which risks coolant leakage and complicates access to control electronics

Engineering Contradiction:
Improvecooling efficiencyVSAvoidmaintenance accessibility
Core Design Contradiction:
TemperatureVSEase of repair

Solution Approach 1:

The stator is divided into two main parts: a closed stator body containing the cooling channels and control electronics, and a removable end plate that seals the open end. This segmentation allows the stator to maintain its cooling function while enabling easy access to control electronics by simply removing the end plate without disconnecting coolant supply.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The control electronics are nested inside the hollow stator body, which itself is nested within the overall motor assembly. The coolant channels are integrated into the stator body structure. This nesting arrangement allows all components to coexist in a compact configuration while maintaining accessibility through the open end design.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Loss of energy

If control electronics are integrated within the stator, then electrical losses are minimized, but access for inspection and repair requires disassembly of the stator

Engineering Contradiction:
Improveelectrical lossesVSAvoidaccessibility for maintenance
Core Design Contradiction:
Loss of energyVSEase of operation

Solution Approach 1:

The stator is segmented into a closed stator body housing the control electronics and a removable end plate. This allows the control electronics to remain integrated within the stator for minimizing electrical losses, while the removable end plate provides easy access for inspection and repair without requiring full disassembly.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The end plate is designed to be removable from the outset, providing preliminary access to the control electronics. This preliminary design feature enables maintenance personnel to access the control electronics quickly without needing to disconnect coolant supply or perform complex disassembly procedures.

Inventive Principle:
Principle #10Preliminary action

3Ease of operation

If coolant channels are disconnected for maintenance, then access to control electronics is possible, but coolant leakage risk increases and reconnection is required

Engineering Contradiction:
ImproveaccessibilityVSAvoidcoolant seal integrity
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The stator is segmented into a closed stator body containing the coolant channels and a removable end plate. This segmentation allows maintenance personnel to access control electronics by simply removing the end plate without disconnecting the coolant supply, thereby maintaining coolant seal integrity while providing easy accessibility.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The removable end plate acts as an intermediary component that provides access to the control electronics without requiring disconnection of the coolant channels. The end plate can be removed and reinstalled without affecting the coolant seal integrity, serving as a convenient access point while maintaining system reliability.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Device complexity

If cooling channels are arranged in series, then cooling path is simple, but cooling efficiency decreases due to temperature gradient along the channel

Engineering Contradiction:
Improvecooling channel configurationVSAvoidcooling efficiency
Core Design Contradiction:
Device complexityVSTemperature

Solution Approach 1:

The cooling channels are segmented into multiple groups arranged in parallel, with each group containing one or more channels. This segmentation allows the coolant to flow through multiple channels simultaneously, reducing the temperature gradient along each individual channel and improving overall cooling efficiency while maintaining a relatively simple configuration.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The cooling channels are arranged in a two-dimensional configuration with multiple groups of parallel channels extending along the stator body. This dimensional arrangement allows the coolant to distribute heat more effectively across the stator surface, improving cooling efficiency without significantly increasing system complexity.

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

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

Enhances cooling efficiency, reduces risk of coolant leakage, and allows for maintenance without disassembling the stator, enabling easier access and inspection of control electronics while keeping the motor attached to the vehicle.

Implementation Method 1

a plurality of cooling channels adapted for circulation of a liquid coolant extends along the hollow stator body and are in fluid connection with said coolant supply duct, wherein the cooling channels are arranged for cooling the electromagnets

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Data Source

PatentEP3656041B1In-wheel motor provided with cooling channels, and a cooling jacket
Publication Date: 2023.09.27 E TRACTION EURO BV
  • EP3656041B1 patent drawingFigure 1A
  • EP3656041B1 patent drawingFigure 1B
  • EP3656041B1 patent drawingFigure 2A~2B

AI summary

An in-wheel motor for a vehicle is disclosed, comprising: a stator with a connector member for attaching the stator to the vehicle, the connector member comprising a shaft, an end plate of a larger diameter than the shaft, and a passage for coolant through said end plate, the stator further comprising a hollow stator body having a cylindrical outer surface and mounted to the connector member, wherein a plurality of cooling channels adapted for circulation of a liquid coolant extends along the hollow stator body and are in fluid connection with said coolant supply duct, said plurality of cooling channels having an inlet for supply of liquid coolant to the plurality of channels and an outlet for discharging liquid coolant from the plurality of channels; wherein, at a side opposite from the connector member, the hollow stator body has an open end with a diameter larger than the diameter of the shaft. The invention further relates to a cooling jacket for such an in-wheel motor.