Inverter Unit Vibration Damping via Elastomeric Adhesive Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated-inverter electric compressors for automobile air conditioners face challenges in achieving sufficient anti-vibration properties while minimizing weight and cost, particularly due to the use of gel-like resins that are heavy and expensive, and difficulties in maintaining control boards encapsulated in resin configurations.
Innovation Solution
The solution involves an inverter unit with a power-system metallic board integrated into a plastic case via insert molding, covered by a thermosetting resin layer for insulation and anti-humidity, and an elastomeric adhesive layer between the CPU board and the resin layer to absorb vibrations, with the elastomeric adhesive specifically applied to areas of high vibration or under heavy components, optimizing resin usage for improved anti-vibration properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If gel-like resin is filled to cover the top face of the CPU board inside the inverter accommodating unit, then insulation properties and anti-humidity properties are ensured and anti-vibration properties are improved, but weight and cost increase significantly
Solution Approach 1:
The patent applies different resin materials to different locations based on specific requirements: thermosetting resin (epoxy or polyurethane) is applied only to the power-system metallic board area for insulation and anti-humidity protection, while elastomeric adhesive is applied only to the CPU board area for vibration absorption. This localized application resolves the contradiction by providing anti-vibration protection where needed without filling the entire inverter accommodating unit, thus avoiding excessive weight increase.
Solution Approach 2:
The patent segments the resin protection into two distinct functional layers: a thermosetting resin layer for the power-system metallic board and an elastomeric adhesive layer for the CPU board. This segmentation allows each layer to perform its specific function (insulation/anti-humidity vs. vibration absorption) without requiring a single comprehensive resin filling, thereby reducing overall weight while maintaining reliability.
2Reliability
If gel-like resin is filled to cover the top face of the CPU board, then insulation properties and anti-humidity properties are ensured, but cost increases due to expensive resin material
Solution Approach 1:
The patent applies resin protection locally rather than universally: thermosetting resin is applied only to the power-system metallic board area where insulation and anti-humidity protection are most critical, and elastomeric adhesive is applied only to the CPU board area. This localized approach resolves the contradiction by providing necessary protection where needed while significantly reducing the total amount of expensive resin required, thus lowering manufacturing cost.
Solution Approach 2:
The patent uses partial action by applying resin only to specific areas rather than filling the entire inverter accommodating unit. The thermosetting resin layer covers only the power-system metallic board, and the elastomeric adhesive covers only the CPU board area, providing sufficient protection without the excessive resin application that would drive up costs.
3Reliability
If control board is encapsulated in resin configuration, then anti-vibration properties are improved, but maintenance becomes difficult
Solution Approach 1:
The patent applies elastomeric adhesive locally to the CPU board area rather than fully encapsulating the entire control board assembly. This localized vibration absorption layer provides anti-vibration protection to the CPU board while leaving other parts of the control board accessible, resolving the contradiction by maintaining protectiveness where needed while preserving maintainability of the overall control board assembly.
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 effectively secures and protects the semiconductor switching elements and CPU board with reduced resin usage, enhancing anti-vibration properties and reducing the weight and cost of the inverter unit while maintaining insulation and anti-humidity protection.
Implementation Method 1
a vibration-absorbing elastomeric adhesive layer that maintains a rubber state in an operating temperature range of the electric compressor is provided between a bottom face of the CPU board and the thermosetting resin layer
Implementation Method 2
a thermosetting resin layer for insulation and anti-humidity purposes is provided so as to cover a top face of the power-system metallic board
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An integrated-inverter electric compressor and an inverter unit thereof are provided, with which sufficient anti-vibration properties can be ensured and weight reduction can be achieved. In an integrated-inverter electric compressor (1), an inverter unit (20) includes an inverter module (23) in which a power-system metallic board (21) having mounted thereon semiconductor switching elements and so forth is integrated with a plastic case (22), and a CPU board (30) having mounted thereon a control and communication circuit that operates at a low voltage, such as a CPU, is provided on a top face of the inverter module (23), and inside the plastic case (22), a thermosetting resin layer (34) for insulation and anti-humidity purposes is provided so as to cover a top face of the power-system metallic board (21), and a vibration-absorbing elastomeric adhesive layer (35, 35A) that maintains a rubber state in an operating temperature range of the integrated-inverter electric compressor (1) is provided between a bottom face of the CPU board (30) and the thermosetting resin layer (34).