Aluminum electrolytic capacitor
By replacing rubber plugs with limiting components and sealing insulation components in aluminum electrolytic capacitors, and combining them with sealant, the problem of easy corrosion of the seal is solved, resulting in better sealing effect and smaller capacitor size.
Patent Information
- Application Number
- CN202511432588.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-09
- Publication Date
- 2026-01-06
AI Technical Summary
Existing aluminum electrolytic capacitors are prone to corrosion under high salt and high humidity conditions, which affects their service life.
By replacing the traditional rubber plug with limiting components and sealing insulation components, a sealed insulation structure is formed through the sealing connection between the sealing insulation components and the anode and cathode guide pins, combined with the use of sealant.
It improves the sealing effect, reduces the risk of corrosion, and reduces the size of the capacitor.
Smart Images
Figure CN121282010A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to an aluminum electrolytic capacitor, and more particularly to an aluminum electrolytic capacitor with a novel packaging structure. Background Technology
[0002] Modern leaded aluminum electrolytic capacitors typically achieve sealing through a waist between the casing and the rubber stopper, as well as a rolled edge on the top of the casing. Under high salt and high humidity conditions, the rolled edge is highly susceptible to corrosion, which can cause sealing problems and affect the lifespan of the aluminum electrolytic capacitor. Summary of the Invention
[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an aluminum electrolytic capacitor.
[0004] To solve the above-mentioned technical problems, the technical solution proposed by the present invention is as follows: an aluminum electrolytic capacitor, comprising a shell, a core, and a sealing connection portion. The core is sealed inside the shell through the sealing connection portion. The shell includes a bottom cover and a housing. The bottom of the housing is open, and the bottom cover is sealed to the open end of the bottom of the housing. One end of the anode and cathode leads on the core abuts against the top of the housing. The top of the housing is provided with a sealing connection portion for the anode and cathode leads. The sealing connection portion includes a sealing insulation component and a limiting component. The limiting component is shaped like a frustum conical or a cylinder. After the sealant is injected into the limiting component and cured, it forms a sealing insulation component. The sealing insulation component seals the limiting component with the anode and cathode leads.
[0005] Preferably, in the aluminum electrolytic capacitor described above, the limiting member and the housing are integrally formed.
[0006] In the aforementioned aluminum electrolytic capacitor, preferably, the top of the casing is recessed downward to form an indented platform, and the limiting member is disposed on the indented platform; one end of the anode guide pin and the cathode guide pin on the core package abuts against the indented platform.
[0007] In the aforementioned aluminum electrolytic capacitor, preferably, the depth of the recess at the top of the casing is greater than or equal to the height of the limiting member.
[0008] Preferably, in the aluminum electrolytic capacitor described above, the cavity formed by the recess at the top of the casing is filled with sealant, and the thickness of the sealant is greater than the height of the limiting member.
[0009] Preferably, in the aforementioned aluminum electrolytic capacitor, the core package includes an anode foil, an electrolytic paper, and a cathode foil, with the electrolytic paper disposed between the anode foil and the cathode foil; the electrolytic paper extends beyond both ends of the core package, and after the bottom cover is welded to the housing, the electrolytic paper extending from the bottom of the core package contacts the bottom cover.
[0010] Compared with the prior art, the advantages of the present invention are as follows: In the present invention, the anode and cathode leads do not use traditional rubber plugs at the protruding ends of the housing, but instead use limiting parts and sealing insulation parts, eliminating the need for rolled edge sealing, thus resulting in better sealing effect; and it can reduce the size of aluminum electrolytic capacitors. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the aluminum electrolytic capacitor in Example 1.
[0012] Figure 2 This is a schematic diagram of the assembly structure of the aluminum electrolytic capacitor in Example 1.
[0013] Figure 3 This is a schematic diagram of the assembly structure of the aluminum electrolytic capacitor filled with sealant in Example 1.
[0014] Legend
[0015] 1. Outer shell; 11. Housing; 12. Bottom cover; 13. Recessed platform; 2. Core package; 3. Sealed connection; 31. Sealed insulation component; 32. Limiting component; 4. Aluminum rod; 5. Lead wire; 6. Sealant. Detailed Implementation
[0016] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.
[0017] It should be noted that when a component is described as being "fixed to, attached to, connected to or connected to" another component, it can be directly fixed to, attached to, connected to or connected to the other component, or it can be indirectly fixed to, attached to, connected to or connected to the other component through other intermediate connectors.
[0018] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.
[0019] Example 1
[0020] like Figure 1 and Figure 2An aluminum electrolytic capacitor is shown, comprising a housing 1, a core 2, and a sealing connection 3. The core 2 is sealed within the housing 1 via the sealing connection 3. The housing 1 includes a bottom cover 12 and a shell 11. The shell 11 has an opening at the bottom, and the bottom cover 12 is sealed to the opening at the bottom of the shell 11. The top of the shell 11 is provided with a sealing connection 3 for an anode guide pin and a cathode guide pin. The sealing connection 3 includes a sealing insulation component 31 and a limiting component 32. The limiting component 32 is truncated cone or cylindrical, and has an opening at the top. Sealing adhesive is injected into the limiting component 32 and cured to form the sealing insulation component 31. The sealing insulation component 31 seals the limiting component 32 with the anode guide pin and the cathode guide pin. The diameter of the opening at the top of the limiting component is larger than the diameter of the aluminum stem of the anode or cathode guide pin, preferably 1.5 times the diameter of the aluminum stem. In this embodiment, one end of the anode and cathode guide pins on the core package presses against the top of the housing; thus, when the sealant is injected into the limiting member 32, the sealant is confined within the space of the limiting member.
[0021] In this embodiment, the core package 2 includes an anode foil, electrolytic paper, and a cathode foil, with the electrolytic paper disposed between the anode foil and the cathode foil. The electrolytic paper extends beyond both ends of the core package 2. After the bottom cover 12 is welded to the housing 11, the electrolytic paper extending from the bottom of the core package 2 contacts the bottom cover 12. Thus, the bottom cover 12 provides a certain degree of fixation for the core package 2. In this embodiment, the electrolytic paper extends from one end of the anode and cathode guide pins. When the sealant is injected into the limiting member, the anode and cathode guide pins on the core package press against the top of the housing, meaning the electrolytic paper at the top of the core package presses against the top of the housing. However, the force exerted is relatively small, preventing excessive stress on the core package body. Therefore, when the sealant is injected into the limiting member, the electrolytic paper extending from the top of the core package separates the core package body from the sealant, thus minimizing the impact of the sealant on the core package body.
[0022] In this embodiment, the limiting member 32 and the housing 11 are integrally formed; thus, there is no sealing problem between the limiting member 32 and the housing 11.
[0023] In this embodiment, an anode guide pin and a cathode guide pin are riveted to the anode foil and cathode foil, respectively. The anode guide pin and cathode guide pin have the same structure, both including an aluminum tongue, an aluminum stem 4, and a lead wire 5. The aluminum tongue is riveted to the anode foil or cathode foil, and the aluminum stem 4 is located between the aluminum tongue and the lead wire 5. The diameter of the aluminum stem 4 is at least 1.5 times the diameter of the lead wire 5. In this embodiment, the aluminum stem is positioned within the space enclosed by the limiting member and the top of the core package; the upper part of the aluminum stem may also extend beyond the limiting member 32.
[0024] In this embodiment, a method for preparing an aluminum electrolytic capacitor is also provided, comprising the following steps:
[0025] 1) Wind the anode foil, electrolytic paper, and cathode foil into a core package;
[0026] 2) Pass the anode and cathode guide pins on the core package through the limiting member to fix the housing 11;
[0027] 3) Clamp the leads of the anode and cathode guide pins so that the top of the core package 2 presses against the top of the housing 11. At this time, the aluminum stems of the anode and cathode guide pins are located within the space of the limiting member 32.
[0028] 4) Inject sealant into the limiting member 32. After the sealant is heated and cured, it creates a sealed connection between the limiting member 32 and the anode guide pin and the cathode.
[0029] 5) Impregnate the casing and core package together with the electrolyte;
[0030] 6) The bottom cover 12 and the housing 11 are sealed together by laser welding.
[0031] As can be seen from the above, when assembling the aluminum electrolytic capacitor in this embodiment, firstly, the anode and cathode leads on the core package are passed through the limiting member to fix the housing 11; then, the leads of the anode and cathode leads are clamped so that the top of the core package 2 presses against the top of the housing 11, at which point the aluminum stems of the anode and cathode leads are positioned within the space of the limiting member 32; then, sealant is injected into the limiting member 32, and after the sealant is heated and cured, a sealed connection is formed between the limiting member 32 and the anode and cathode leads; then, the housing and core package are impregnated with electrolyte, and finally, the bottom cover 12 is sealed to the housing 11 by laser welding. In this embodiment, when the sealant is heated and cured to form the sealing insulation 31, the core package 2 is not impregnated with electrolyte, and no air bubbles are generated inside the sealing insulation when the sealant is heated and cured.
[0032] In this embodiment, as Figure 1 and Figure 2 As shown, the top of the housing 11 is recessed downwards to form a recessed platform 13, and the limiting member 32 is disposed on the recessed platform 13. The depth of the recessed platform 13 formed by the top of the housing 11 is greater than or equal to the height of the limiting member 32; thus, the limiting member 32 is housed within the recessed space, thereby facilitating installation on the circuit board; in particular, the recessed space provides sufficient space for reflow soldering on the circuit board, thereby reducing the impact of temperature on the interior of the core package 2 during reflow soldering.
[0033] In this embodiment, to further enhance the sealing performance, it can be done as follows: Figure 3As shown, the cavity formed by the recess at the top of the housing 11 is filled with sealant 6, and the thickness of sealant 6 is greater than the height of the limiting member 32. The sealant 6 fills and seals the limiting member 32, which greatly increases the sealing performance between the sealing insulation member 31, the limiting member 32, and the aluminum rod 4.
[0034] In this invention, the anode and cathode leads do not use traditional rubber plugs at the protruding ends of the housing 1. Instead, they are replaced by a limiting member 32 and a sealing and insulating member 31. There is no need to use rolled edge sealing, so the sealing effect is better; and the size of the aluminum electrolytic capacitor can be reduced.
Claims
1. An aluminum electrolytic capacitor comprising a case, a core package, and a sealing connecting portion, the core package being sealedly disposed in the case by the sealing connecting portion, characterized by: The shell comprises a bottom cover and a shell body, the bottom of the shell body is open, the bottom cover is sealingly connected with the open end of the bottom of the shell body, and one end of the anode guide needle and the cathode guide needle on the core package abuts against the top of the shell body; the top of the shell body is provided with a sealing connection part of the anode guide needle and the cathode guide needle; the sealing connection part comprises a sealing insulation part and a limiting part, the limiting part is in the shape of a truncated cone or a cylinder, and sealing glue is injected into the limiting part to form the sealing insulation part after solidification; the limiting part is sealingly connected with the anode guide needle and the cathode guide needle through the sealing insulation part.
2. The aluminum electrolytic capacitor according to claim 1, characterized by: The limiting part and the shell body are integrally formed.
3. The aluminum electrolytic capacitor according to claim 1, characterized by: The top of the shell body is concave downward to form an inner recess platform, and the limiting part is arranged on the inner recess platform; one end of the anode guide needle and the cathode guide needle on the core package abuts against the inner recess platform.
4. The aluminum electrolytic capacitor according to claim 3, characterized by: The depth of the inner recess of the top of the shell body is greater than or equal to the height of the limiting part.
5. The aluminum electrolytic capacitor according to claim 3, wherein: The cavity formed by the inner recess of the top of the shell body is filled with sealing glue, and the thickness of the sealing glue is greater than the height of the limiting part.
6. The aluminum electrolytic capacitor according to any one of claims 1 to 5, characterized by: The core package comprises an anode foil, an electrolytic paper and a cathode foil, the electrolytic paper is arranged between the anode foil and the cathode foil, the electrolytic paper extends out of both ends of the core package, and the electrolytic paper extending out of the bottom of the core package is in contact with the bottom cover after the bottom cover is welded with the shell body.