Axial Flow Blower Motor Cooling via Pressure Differential
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional axial flow blowers are ineffective in cooling the motor due to the difficulty in introducing high-speed air flow into the motor case, resulting in inadequate cooling.
Innovation Solution
An axial flow blower design that includes an air communication passage between the outside and the motor case, with outflow holes allowing ambient air to be suctioned into the motor case, creating a cooling effect by generating a pressure difference that draws air into the motor case and outflow into the air blow passage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If an air communication hole is formed through the motor case to enable motor cooling, then the motor cooling capability is improved, but the high speed air flow cannot effectively enter the motor case resulting in insufficient cooling effect
Solution Approach 1:
A guide passage is introduced as an intermediary structure that directs the high-speed air flow from the air blow passage toward the air communication hole. This guide passage acts as a mediator to channel the air flow that would otherwise miss the motor case, enabling the high-speed air to effectively enter the motor case through the air communication hole and achieve proper cooling.
2Reliability
If the motor case is sealed to protect the motor, then the motor protection is improved, but the motor cooling effect deteriorates due to inability to introduce air flow
Solution Approach 1:
The motor case is segmented into multiple functional zones: a sealed portion that protects the motor, and controlled openings (air communication hole and outflow hole) that enable cooling. The air communication hole allows air entry for cooling while the outflow hole positioned downstream allows cooled air to exit, creating a controlled cooling pathway that maintains overall motor case sealing for protection.
3Temperature
If air is introduced into the motor case for cooling, then the motor cooling effect is improved, but the air flow efficiency deteriorates due to air not being effectively utilized in the air blow passage
Solution Approach 1:
The cooling air flow path is merged with the air blow passage flow path. Air that cools the motor through the air communication hole and passes over the motor components is directed to exit through the outflow hole into the air blow passage, where it joins the main air flow. This merging allows the cooling air to be reused in the air blow function, improving overall air flow efficiency.
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 design efficiently introduces ambient air into the motor case, effectively cooling the motor by utilizing the pressure difference to enhance airflow and cooling efficiency.
Implementation Method 1
when the air blow fan rotates to generate an air flow in the air blow passage, an inside of the air blow passage has a lower pressure than the an inside of the motor case does and the air in the motor case is suctioned into the air blow passage
Implementation Method 2
this air flow cools down the motor
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An axial flow blower comprises a housing having a suction opening and an ejection opening formed thereon and having an air blow passage formed therein through which the suction opening and the ejection opening are in communication with each other, a motor case disposed in the air blow passage, a motor housed in the motor case, an air blow fan connected with a driven section of the motor and configured to rotate on a driving force of the motor to blow air from the suction opening toward the ejection opening and an air communication passage provided between an outside of the air blow passage and an inside of the motor case. An outflow hole is bored through the motor case and in communication with the air blow passage and an outer space outside the housing is in communication with an inner space inside the motor case through the air communication passage.