Rotating Electric Machine Housing Layout for Full-Circumference Cooling

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In cooling rotating electric machines, a large number of refrigerant liquid feeding ports leads to a decrease in the spraying force of each nozzle, necessitating a reduction in the number of ports to maintain effective cooling.

Innovation Solution

A device with a housing that includes a refrigerant liquid feeding member with a limited number of ports, where the refrigerant liquid is introduced at the upper part and forms a reservoir at the lower part, allowing for efficient cooling of the lower side without the need for additional ports.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If refrigerant liquid feeding ports are provided across the entire circumference of the rotating electric machine, then the cooling coverage is improved, but the spraying force of each nozzle decreases

Engineering Contradiction:

Improvecooling coverageVSAvoidspraying force

Core Design Contradiction:

TemperatureVSForce

Solution Approach 1:

The housing is divided into an upper part with refrigerant liquid feeding ports and a lower part with a refrigerant liquid reservoir. This segmentation allows the upper nozzles to focus spraying force on the upper stator while the lower stator is cooled by the reservoir, thereby maintaining high spraying force per nozzle while achieving full circumferential cooling coverage.

Inventive Principle:

Principle #1Segmentation

2Temperature

If the number of refrigerant liquid feeding ports is increased, then the cooling coverage is improved, but the complexity of the device increases

Engineering Contradiction:

Improvecooling coverageVSAvoidnumber of ports

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The refrigerant liquid reservoir at the lower part of the housing combines the functions of a cooling chamber and a liquid storage tank. This merging eliminates the need for separate refrigerant liquid feeding ports in the lower part, reducing the total number of ports while maintaining comprehensive cooling coverage through gravitational flow from the upper ports.

Inventive Principle:

Principle #5Merging (Combining)

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

This configuration reduces the number of refrigerant liquid feeding ports required, maintaining effective cooling while minimizing the number of ports needed, thus optimizing the cooling process.

Implementation Method 1

refrigerant liquid flowing down from the upper part of the housing

Methodology Applied

Scientific EffectGravitational convection: Gravitational Convection (non heat)

Implementation Method 2

at least the lower part side of the housing can be cooled by the refrigerant liquid

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentUS11990824B2Device including rotating electric machine and housing with introduction port

Publication Date: 2024.05.21 JATCO LTD

AI summary

The power transmission device has the rotating electric machine, the housing that houses the stator of the rotating electric machine, and the pipe as a refrigerant liquid feeding member that has the holes. In the upper part of the housing is provided the opening that introduces oil ejected from the holes. In the lower part of the housing is provided the oil reservoir that forms an oil pool.