Rotary Electric Machine Shaft Cooling With Integrated Current Shunter

Solution Overview

Problem

Rotary electric machines with charge dissipating devices and nozzle members for cooling require additional fixing members, increasing the number of parts and complicating assembly.

Innovation Solution

A rotary electric machine design that incorporates a rotor with a hollow shaft, a stator, a housing, bearings, a current shunter fixed to the housing for electrical contact, and a nozzle member with a feeding tubular part and flange portion, where the flange portion is located between the current shunter and the housing bottom wall, reducing the need for additional fixing members by using the current shunter to secure the nozzle member.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a current shunter and nozzle member are separately fixed to the housing, then both components can be securely mounted, but the number of parts increases and assembly becomes more complex

Engineering Contradiction:

Improvesecure mountingVSAvoidnumber of parts

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The current shunter and nozzle member are integrated into a single component structure. The current shunter serves dual functions: it provides electrical contact with the rotating shaft and simultaneously acts as a mounting structure for the nozzle member. This merging eliminates the need for separate fixing members, reducing the total number of parts while maintaining secure mounting of both components.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The current shunter is designed with multi-functionality: it conducts electricity from the rotating shaft to the housing, provides structural support, and serves as a mounting base for the nozzle member. By making the current shunter a universal component that performs multiple functions, the patent eliminates the need for additional dedicated fixing members, thereby reducing part count and simplifying assembly.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If additional fixing members are used to secure both the current shunter and nozzle member, then both components are properly positioned, but assembly time and labor increase

Engineering Contradiction:

Improvecomponent positioningVSAvoidassembly time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The current shunter and nozzle member are integrated into a single component structure. The current shunter serves dual functions: it provides electrical contact with the rotating shaft and simultaneously acts as a mounting structure for the nozzle member. This merging eliminates the need for separate fixing members, reducing the total number of parts while maintaining secure mounting of both components.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The current shunter is designed with multi-functionality: it conducts electricity from the rotating shaft to the housing, provides structural support, and serves as a mounting base for the nozzle member. By making the current shunter a universal component that performs multiple functions, the patent eliminates the need for additional dedicated fixing members, thereby reducing part count and simplifying assembly.

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

This design reduces the number of parts and simplifies assembly by using the current shunter to attach the nozzle member, minimizing man-hours and time required for assembly while maintaining effective electrical contact and fluid feeding functionality.

Implementation Method 1

a current shunter that is fixed to the housing and is in electrical contact with the shaft and the housing

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 2

a nozzle member that feeds a fluid into inside the shaft

Methodology Applied

Scientific EffectFluid flow:

Data Source

PatentUS11863043B2Rotary electric machine and drive device

Publication Date: 2024.01.02 NIDEC CORP(JP)

AI summary

A rotary electric machine includes a rotor having a hollow shaft, a housing, a current shunter fixed to the housing and in electrical contact with the shaft and the housing, and a nozzle member for feeding a fluid inside the shaft. The shaft has an open end portion on a first axial side. The housing includes a bottom wall on the first axial side from the open end portion, and a peripheral wall protruding from the bottom wall toward a second axial side and surrounding the open end portion. The nozzle member has a feeding tubular part at least partly inserted inside the shaft from the open end portion, and a flange portion protruding radially outward from the feeding tubular part. The current shunter is located radially inside the peripheral wall, and the flange portion is located between the current shunter and the bottom wall in an axial direction.