Electrolytic Capacitor Mold Structure for Leakage Current Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing electrolytic capacitors with porous sintered bodies result in uneven density distribution of valve metal particles, leading to reduced capacitance and increased leakage current due to excessive bonding and density differences near the anode wire planting surface.
Innovation Solution
A mold design with slidable upper and lower mold parts forms an initial space with a step portion, allowing metal particles to move and distribute evenly, reducing density differences by integrating the mold parts to eliminate the step portion and ensure uniform particle density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If valve metal particles are pressure-molded using a conventional mold, then the capacitor can be manufactured, but the density of particles near the anode wire planting surface becomes sparse, reducing manufacturing precision
Solution Approach 1:
The mold cavity is designed with a stepped structure where a first mold part defines a first cavity portion and a second mold part defines a second cavity portion at a different position. This preliminary spatial arrangement ensures that valve metal particles are distributed more uniformly before the actual pressure molding occurs, preventing sparse density near the anode wire planting surface and improving both manufacturing precision and anode wire fixation strength.
2Ease of operation
If the anode wire is planted in a region with sparse particle density, then the wire can be inserted, but the wire is not sufficiently fixed in the molded body, reducing reliability
Solution Approach 1:
The stepped mold cavity structure is designed in advance to create a region with higher particle density where the anode wire will be planted. This preliminary action ensures that when the wire is inserted, it is surrounded by sufficiently dense particles that will provide strong fixation after molding, thus maintaining both ease of insertion and high reliability.
3Productivity
If pressure molding is performed with a conventional mold, then the capacitor body is formed, but uneven particle density causes excessive bonding and increased leakage current, reducing product quality
Solution Approach 1:
The mold cavity is segmented into a first cavity portion defined by a first mold part and a second cavity portion defined by a second mold part. This segmentation allows different regions of the capacitor body to have optimized particle density distributions, preventing excessive bonding and leakage current while maintaining high molding efficiency through the integrated stepped structure.
Data Source
AI summary
An electrolytic capacitor including a porous sintered body formed by a mold. The electrolytic capacitor element including the porous sintered body having a first surface, a second surface opposed to the first surface, a third surface and a fourth surface that are opposed to each other and intersect the first surface and the second surface, and a fifth surface and a sixth surface that are opposed to each other and intersect the first surface, the second surface, the third surface, and the fourth surface. The porous sintered body satisfies a relationship of La≤Lb, where La represents a shortest length in the longitudinal direction from the boundary line to the first surface and Lb represents a shortest length in the longitudinal direction from the boundary line to the second surface, when viewed from a normal direction of the fifth surface or the sixth surface.