An aluminum electrolytic capacitor

Abstract

An aluminum electrolytic capacitor comprises a shell, a core package and a sealing connecting part, the core package is sealingly arranged in the shell through the sealing connecting part, 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 anode lead pins and cathode lead pins on the core package abuts against the top of the shell body; the top of the shell body is provided with the sealing connecting part of the anode lead pins and the cathode lead pins; the sealing connecting part comprises a sealing insulating part and a limiting part, the limiting part is in the shape of a truncated cone or a cylinder, sealing glue is injected into the limiting part to form the sealing insulating part after solidification, and the sealing insulating part sealingly connects the limiting part with the anode lead pins and the cathode lead pins. In the utility model, the traditional rubber plug is not used at the extending end of the anode lead pins and the cathode lead pins in the shell, instead, the limiting part and the sealing insulating part are used, and the crimping sealing is not needed, so that the sealing effect is better.

Description

Technical Field

[0001] This utility model 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. Utility Model Content

[0003] The technical problem to be solved by this utility model 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 this utility model is as follows: an aluminum electrolytic capacitor, comprising a shell, a core, and a sealing connection part. The core is sealed inside the shell through the sealing connection part. 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 part for the anode and cathode leads. The sealing connection part 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 this utility model are as follows: In this utility model, the anode and cathode guide pins do not use traditional rubber plugs at the protruding ends of the outer shell, 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 this utility model, it will be described more comprehensively and in detail below with reference to the accompanying drawings and preferred embodiments. However, the scope of protection of this utility model 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 protection of this 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 extended 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 casing, a core, and a sealing connection, wherein the core is sealed within the casing via the sealing connection, characterized in that: The outer casing 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 guide pin and the cathode guide pin on the core package abuts against the top of the housing. The top of the housing is provided with a sealed connection part for the anode guide pin and the cathode guide pin. The sealed connection part includes a sealing insulation component and a limiting component. The limiting component is in the shape of a frustum cone 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 connection between the limiting component and the anode guide pin and the cathode guide pin.

2. The aluminum electrolytic capacitor according to claim 1, characterized in that: The limiting component and the housing are integrally formed.

3. The aluminum electrolytic capacitor according to claim 1, characterized in that: The top of the housing is recessed downward to form an indented platform, and the limiting member is disposed on the indented platform; one end of the anode guide needle and the cathode guide needle on the core package abuts against the indented platform.

4. The aluminum electrolytic capacitor according to claim 3, characterized in that: The depth of the recess at the top of the housing is greater than or equal to the height of the limiting member.

5. The aluminum electrolytic capacitor according to claim 3, characterized in that: The cavity formed by the recess at the top of the housing is filled with sealant, and the thickness of the sealant is greater than the height of the limiting member.

6. The aluminum electrolytic capacitor according to any one of claims 1-5, characterized in that: 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. After the bottom cover is welded to the shell, the electrolytic paper extending from the bottom of the core package contacts the bottom cover.

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