Motor Internal Coolant Supply Path Segmentation

Solution Overview

Problem

Conventional motor cooling methods are inefficient in cooling the stator winding and rotor, leading to increased bearing temperatures and reduced lifespan due to inadequate heat dissipation.

Innovation Solution

A motor design incorporating an internal coolant supply path with temperature-measured switching parts that selectively switch between different coolants, amounts, and flow paths to efficiently cool the motor, utilizing both air-purge and quick-cooling nitrogen based on temperature readings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If conventional cooling methods are used based on inside temperature detection, then the motor can be cooled to some extent, but the stator winding and rotor cannot be sufficiently cooled

Engineering Contradiction:

Improvestator winding temperatureVSAvoidcooling effectiveness

Core Design Contradiction:

TemperatureVSReliability

Solution Approach 1:

The cooling system is segmented into multiple independent coolant supply paths: a first coolant supply path for the stator winding, a second coolant supply path for the rotor, and a third coolant supply path for the bearing. This segmentation allows each component to be cooled independently and effectively, addressing the insufficient cooling of specific components while maintaining overall system reliability.

Inventive Principle:

Principle #1Segmentation

2Temperature

If conventional cooling methods are used based on inside temperature detection, then the motor can be cooled to some extent, but the rotor cooling is insufficient leading to bearing temperature rise

Engineering Contradiction:

Improverotor temperatureVSAvoidbearing lifespan

Core Design Contradiction:

TemperatureVSReliability

Solution Approach 1:

The cooling system is segmented into multiple independent coolant supply paths: a first coolant supply path for the stator winding, a second coolant supply path for the rotor, and a third coolant supply path for the bearing. This segmentation allows each component to be cooled independently and effectively, addressing the insufficient cooling of specific components while maintaining overall system reliability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different cooling strategies are applied to different locations based on their specific thermal requirements. The stator winding receives coolant through one path, the rotor through another, and the bearing through a third path. This localized cooling approach ensures that each component is cooled appropriately for its function and thermal characteristics, preventing bearing temperature rise while maintaining rotor cooling effectiveness.

Inventive Principle:

Principle #3Local quality

3Reliability

If a single coolant supply path is used, then the device complexity is low, but the cooling efficiency for different components is insufficient

Engineering Contradiction:

Improvecooling efficiencyVSAvoidcoolant supply path complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The cooling system is segmented into multiple independent coolant supply paths: a first coolant supply path for the stator winding, a second coolant supply path for the rotor, and a third coolant supply path for the bearing. This segmentation allows each component to be cooled independently and effectively, addressing the insufficient cooling of specific components while maintaining overall system reliability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The coolant supply system is designed with multi-functionality to address multiple cooling needs simultaneously. The same coolant type can be used across different paths, and the system can adaptively control coolant flow to different components based on their thermal requirements. This universal approach maintains system simplicity while achieving component-specific cooling efficiency.

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 effectively suppresses temperature rises, enhances motor performance, and extends service life by ensuring efficient coolant distribution and resource-saving cooling strategies.

Implementation Method 1

coolant is supplied to the coolant flow path... capable of efficiently cooling the motor

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

coolant flow path that supplies coolant... internal coolant circulation path... coolant discharge path

Methodology Applied

Scientific EffectConvection: Convection

Data Source

PatentUS10224780B2Motor having internal coolant supply passage

Publication Date: 2019.03.05 FANUC LTD

AI summary

A motor includes: a rotor; an enclosure member having a front housing, a rear housing, and a stator surrounding the rotor; an output shaft-side coolant supply port on an outer circumference of the enclosure member; output shaft-side coolant supply paths configured to supply coolant from the output shaft-side coolant supply port to an output shaft side; a counter-output shaft-side coolant supply port on the outer circumference of the enclosure member; counter-output shaft-side coolant supply paths configured to supply coolant from the counter-output shaft-side supply port to a counter-output shaft side; a temperature measurement unit configured to measure a temperature of the enclosure member; switching parts configured to switch between a plurality of coolants based on the temperature of the enclosure member; and coolant flow paths that connect the output shaft-side coolant supply port and the counter-output shaft-side coolant supply port to the switching parts.