Power Tool Control Board Heat Dissipation for High-Current MOSFETs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Power tools generate excessive heat due to MOSFETs and motor wire connections, leading to poor heat dissipation and potential failure when working currents are high, affecting normal operation.
Innovation Solution
Incorporation of heat dissipation elements with copper strips that are thermally and electrically connected to circuit boards and motor wires, enhancing heat transfer and reducing overall volume by optimizing connection paths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If MOSFETs are used on the circuit board to control the electric motor, then the power tool can operate with high working current, but excessive heat is generated leading to poor heat dissipation
Solution Approach 1:
The patent extracts the heat dissipation function from the traditional circuit board design by adding separate heat dissipation elements (aluminum strips) that are thermally coupled to the MOSFETs. These heat dissipation elements extend outward from the circuit board to provide dedicated heat dissipation pathways, separating the heat generation function (MOSFETs) from the heat dissipation function (aluminum strips).
Solution Approach 2:
The aluminum heat dissipation elements serve multiple functions: they act as thermal conduction paths to transfer heat from MOSFETs, provide electrical connection between circuit board layers, and serve as structural support elements. This multi-functionality reduces the need for separate components and optimizes space utilization.
2Temperature
If heat dissipation elements are added to the circuit board, then heat dissipation from MOSFETs is improved, but the device complexity increases
Solution Approach 1:
The patent merges multiple functions into the heat dissipation elements: thermal conduction, electrical connection, and structural support are all integrated into the same aluminum strip components. This consolidation reduces the total number of separate parts needed and simplifies the overall assembly process.
Solution Approach 2:
The heat dissipation elements are segmented into specific regions: a first connection portion for electrical connection to the circuit board, a main body for thermal contact with MOSFETs, and a second connection portion for extending connections. This segmentation allows each portion to be optimized for its specific function while maintaining overall simplicity.
3Temperature
If the heat dissipation element includes extended connection portions, then heat transfer path is optimized, but the volume of the component increases
Solution Approach 1:
The heat dissipation elements extend in the vertical dimension (thickness direction) of the circuit board rather than only in the planar dimensions. The first connection portion extends downward from the main body, and the second connection portion extends upward, utilizing the third dimension to create heat transfer pathways without significantly increasing the planar footprint.
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
Effectively dissipates heat from MOSFETs and motor wire connections, ensuring the power tool operates efficiently even at high working currents and powers.
Implementation Method 1
a main body configured to be in thermal contact with a surface of a power element
Implementation Method 2
effectively dissipates heat from MOSFETs and motor wire connections
Data Source
AI summary
A power tool includes: a working assembly configured to perform work of the power tool; a drive assembly including an electric motor and configured to drive the working assembly; a power supply assembly configured to supply power to the drive assembly; and a control assembly at least configured to control running of the electric motor. The control assembly includes a first circuit board and at least one heat dissipation element. At least one power element is included on the first circuit board. Each heat dissipation element includes: a main body configured to be in thermal contact with a surface of a power element; and a first connection portion connected to the main body and electrically connected to the first circuit board.