Capacitor Module Fixing Member Reduces Sealing Stress
Solution Overview
Problem
The sealing strength of capacitor modules is degraded due to stress applied to the sealing curling portion during capacitor attachment, leading to performance issues and potential water accumulation, which affects the connection and fixative properties.
Innovation Solution
A capacitor module design that includes a fixing member inserted between the case member and the capacitor, creating a space to avoid stress on the sealing curling portion and reduce vibration-induced loads on external terminals, while also preventing water accumulation through water discharging holes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the space between the capacitor and case member is filled with insulation resin, then the anchorage strength and insulation property are improved, but the weight reduction is obstructed
Solution Approach 1:
The patent replaces the insulation resin (a material that adds weight) with air spaces and fixing members that provide the same anchorage function without the additional weight. The fixing members are simple structural elements that hold the capacitor in place without requiring filler materials.
2Reliability
If the space between the capacitor and case member is filled with insulation resin, then the insulation property is improved, but the weight reduction is obstructed
Solution Approach 1:
The patent uses air as the insulating medium instead of insulation resin, eliminating the need for additional insulating materials that would increase weight. The wiring substrate and fixing members provide structural insulation without requiring filler materials.
3Reliability
If the accommodating portion is molded with inner diameter larger than capacitor outer diameter to form a space, then the sealing curling portion is protected from stress, but the fixation relies only on external terminals and auxiliary terminal connection
Solution Approach 1:
The patent introduces fixing members as intermediary elements between the capacitor and case member. These fixing members provide additional fixation points that distribute the mechanical load, preventing excessive stress on the external terminals and auxiliary terminals while maintaining the protective space around the sealing curling portion.
4Device complexity
If the capacitor is fixed using only external terminals and auxiliary terminal connection, then the structure is simplified, but vibrations cause degradation of connection property and fixative property
Solution Approach 1:
The fixing members act as intermediaries that provide additional fixation points, distributing the mechanical stress from vibrations across multiple contact points rather than concentrating it on the terminal connections. This protects the electrical connections while maintaining structural integrity.
Solution Approach 2:
The fixing members provide pre-established mechanical support that cushions the capacitor against vibrational forces before these forces can degrade the terminal connections. The space around the capacitor also serves as a cushioning element.
Data Source
Figure 1
Figure 2A~2B
Figure 3
AI summary
A capacitor module (2) including a case member having accommodating portions (14) that accommodate plural capacitors (4). A space (32) is included between an inner wall portion of the accommodating portions and the capacitor. A fixing member (16) is disposed in the space. The fixing member includes an annular portion (20) that surrounds a circumferential portion of the capacitor, and a wedge portion (22) that is formed on the annular portion in a direction of intersection with the annular portion. Any stress applied from the case member to the fixing member and a sealing curling portion can thereby be avoided. In addition, any load applied by vibrations to external terminals and an auxiliary terminal can be reduced, and the connection property and the fixing strength can be maintained.