Brushless Motor Cooling via Heat Radiating Surface Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power tools with brushless motors face degraded cooling performance due to gaps between the output transistor and heat radiating members, which can lead to increased heat generation and potential disconnection from the urging force applied during fixation.
Innovation Solution
The heat radiating surface is positioned near the suction port to receive cooler air, with an air passage and fan configuration that ensures continuous airflow, eliminating the need for an additional heat radiating member and reducing external forces on the switching elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a heat radiating member is fixed to the output transistor to improve cooling performance, then heat dissipation is enhanced, but gaps between the output transistor and heat radiating member degrade heat conduction efficiency
Solution Approach 1:
The patent merges the heat radiating member with the housing structure, creating an integrated cooling system where the housing itself serves as the heat dissipation component. This eliminates gaps between separate parts and ensures reliable thermal contact while maintaining effective cooling performance.
2Stability of the object's composition
If the output transistor is fixed by the heat radiating member to provide structural support, then positioning is secured, but urging force applied to the output transistor may break the leg root causing disconnection
Solution Approach 1:
The patent extracts the fixing function from the heat radiating member and implements it through separate fixing structures (such as fixing ribs or dedicated mounting features) on the housing. This separation allows the heat radiating surface to provide thermal management without applying damaging urging forces to the output transistor legs, while still securing stable positioning.
3Temperature
If individual heat radiating members are provided for each switching element to optimize cooling, then thermal management is improved, but device complexity and manufacturing difficulty increase
Solution Approach 1:
The patent implements a universal housing structure that serves multiple functions: structural support, heat dissipation for all switching elements, and air flow guidance. This single multi-functional component replaces multiple individual heat radiating members, reducing device complexity while maintaining effective thermal management across all switching elements.
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 enhances cooling performance by maintaining the heat radiating surface in a cooler atmosphere, reducing the risk of disconnection and component damage, while minimizing the number of components and improving manufacturing efficiency.
Implementation Method 1
a heat radiating surface for radiating heat generated in the switching element
Implementation Method 2
the heat radiating surface is disposed in the neighborhood of the suction port so as to be supplied with the cooling air
Implementation Method 3
A fan may be provided inside the air passage to flow the cooling air therethrough
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
According to an aspect of the present invention, there is provided a power tool including: a housing having a suction port formed thereon to introduce an cooling air from an outside of the housing; and a brushless motor that is housed in the housing and has an electric circuit, the electric circuit having a heat radiating surface, wherein the heat radiating surface is disposed in a neighborhood of the suction port.