Method for manufacturing sealing cover plate of thermoplastic material aluminum electrolytic capacitor

Abstract

The invention relates to the technical field of capacitor sealing cover plates, in particular to a manufacturing method of a thermoplastic material aluminum electrolytic capacitor sealing cover plate. S1, preparing a capacitor cover plate base material; s11, taking a thermoplastic material as a main body material, and adding 10%-50% of long glass fibers into the main body material; s12, adding an auxiliary agent into the mixed material in the step S11, and uniformly stirring the various materials in a mixing machine; s13, putting the uniformly stirred materials into an injection molding machine for injection molding to form a capacitor cover plate base material; s2, preparing a rubber sealing surface of the capacitor cover plate; s21, uniformly mixing ethylene propylene diene monomer and butyl rubber serving as raw materials; and S22, putting the uniformly mixed ethylene propylene diene monomer and butyl rubber into a calender, and carrying out calendering molding to obtain the rubber sealing surface of the capacitor cover plate. The localization of the capacitor sealing cover plate solves the problem that domestic high-end aluminum electrolytic capacitor sealing cover plates are difficult to purchase.

Description

Technical Field

[0001] The invention relates to the technical field of capacitor sealing cover plates, and in particular to a method for manufacturing a thermoplastic aluminum electrolytic capacitor sealing cover plate. Background Art

[0002] The aluminum electrolytic capacitor sealing cover is a component used to enclose and seal the aluminum electrolytic capacitor to ensure the stability of the internal environment of the capacitor and prevent electrolyte leakage. Through specific design and materials, the sealing cover can effectively isolate the external environment and maintain the pressure and chemical environment inside the capacitor stable, thereby extending the service life of the capacitor and ensuring its stable performance.

[0003] However, domestic aluminum electrolytic capacitor sealing covers have always relied on imported materials to meet quality and technical requirements, resulting in difficulty in purchasing high-end aluminum electrolytic capacitor sealing covers. In response to this phenomenon, after long-term research and experiments, we have developed a new type of composite material aluminum electrolytic capacitor sealing cover that uses thermoplastic material to replace thermosetting material. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a method for manufacturing a sealing cover plate of an aluminum electrolytic capacitor made of a thermoplastic material.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for manufacturing a sealing cover plate of an aluminum electrolytic capacitor made of a thermoplastic material comprises the following steps:

[0007] S1. preparing a capacitor cover substrate;

[0008] S11, using thermoplastic material as the main material, and adding 10%-50% long glass fiber into the main material;

[0009] S12, adding an auxiliary agent to the mixed material in step S11, and mixing the various materials in a mixer;

[0010] S13, placing the uniformly mixed multiple materials in an injection molding machine and injection molding them into a capacitor cover substrate;

[0011] S2. Prepare the rubber sealing surface of the capacitor cover;

[0012] S21, using EPDM rubber and butyl rubber as raw materials and mixing them evenly;

[0013] S22, placing the uniformly mixed EPDM rubber and butyl rubber in a calender and calendering them into a rubber sealing surface of a capacitor cover;

[0014] S3, applying adhesive on the entire surface of the prepared capacitor cover substrate;

[0015] S4. Wrap the rubber sealing surface of the capacitor cover plate with the capacitor cover plate substrate, and put the capacitor cover plate substrate and the rubber sealing surface of the capacitor cover plate into a vulcanizer for high-temperature molding through hot vulcanization.

[0016] Preferably, in step S11, the thermoplastic material may be one of PPA, PA66, PA6 and POK.

[0017] Preferably, in step S3, the adhesive is phenolic resin.

[0018] The present invention has the following beneficial effects:

[0019] 1. Using 10%-50% long glass fiber can increase the strength and high temperature resistance of the main material.

[0020] 2. Adding additives allows the additives to react chemically with the main material to form a multi-layer mesh film in the capacitor cover substrate, so that the broken molecular chains of the main material are reconnected, thereby increasing the capacitor cover substrate to form an excellent material with high density, high rigidity and high temperature resistance.

[0021] 3. After injection molding, the main material, long glass fiber and additives tend to be thermosetting materials from thermoplastic materials, and have excellent high temperature resistance. The treated material can withstand a short-term temperature of more than 300 degrees Celsius without melting. After testing, the material can work for a long time at a high temperature of 130 degrees and a low temperature of 50 degrees. After 3000 hours of testing, the material has no obvious changes and can still meet the sealing and technical requirements of aluminum electrolytic capacitors.

[0022] 4. Add adhesive and vulcanize at high temperature to cause a cross-linking reaction between the adhesive, the capacitor cover substrate and the capacitor cover rubber sealing surface, so that the capacitor cover substrate and the capacitor cover rubber sealing surface are well bonded together with high bonding strength. After a long-term high temperature test at 150 degrees, there is no separation between the capacitor cover substrate and the capacitor cover rubber sealing surface for 3000 hours.

[0023] 5. The new composite capacitor cover has changed the single-sided sealing method of the traditional sealing cover. The bottom, edge, and terminal riveting holes are designed with rubber seals to form an all-round sealing surface, thereby better solving the problem of premature failure of aluminum electrolytic capacitors caused by capacity attenuation due to electrolyte leakage and volatilization caused by electrolyte loss.

[0024] 6. The reasonable design of the new capacitor sealing cover makes the aluminum electrolytic capacitor have an excellent sealing effect and extends the service life of the aluminum capacitor. The new composite material capacitor sealing cover has reached the international advanced cover quality level after testing.

[0025] 7. After testing, the chloride ion, fluoride ion, bromide ion, nitrate ion and phosphate ion in the materials are all ≤1PPM, and the sulfate ion is ≤2PPM, which can fully meet the product requirements.

[0026] 8. The localization of capacitor sealing cover plates has solved the problem of difficulty in purchasing domestic high-end aluminum electrolytic capacitor sealing cover plates. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned purpose, features and advantages of the present invention more obvious and easy to understand, the specific implementation of the present invention is described in detail below. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0028] A method for manufacturing a sealing cover plate of an aluminum electrolytic capacitor made of a thermoplastic material comprises the following steps:

[0029] S1. preparing a capacitor cover substrate;

[0030] S11. Use thermoplastic material as the main material, and add 10%-50% long glass fiber into the main material. Using 10%-50% long glass fiber can increase the strength and high temperature resistance of the main material;

[0031] S12, adding an auxiliary agent to the mixed material in step S11, and placing the various materials in a mixer and stirring them evenly, adding the auxiliary agent so that the auxiliary agent and the main material undergo a chemical reaction, forming a multi-layer mesh film in the capacitor cover substrate, so that the broken molecular chains of the main material are reconnected, thereby increasing the capacitor cover substrate to form an excellent material with high density, high rigidity, and high temperature resistance;

[0032] S13, placing the uniformly mixed multiple materials in an injection molding machine and injection molding them into a capacitor cover substrate;

[0033] After injection molding, the main material, long glass fiber and additives tend to change from thermoplastic material to thermosetting material, and have excellent high temperature resistance. The treated material can withstand a short-term temperature of over 300 degrees Celsius without melting. After testing, the material can work for a long time at temperatures of 130 degrees and 50 degrees. After 3000 hours of testing, the material has no obvious changes and can still meet the sealing and technical requirements of aluminum electrolytic capacitors.

[0034] S2. Prepare the rubber sealing surface of the capacitor cover;

[0035] S21, using EPDM rubber and butyl rubber as raw materials and mixing them evenly;

[0036] S22, placing the uniformly mixed EPDM rubber and butyl rubber in a calender and calendering them into a rubber sealing surface of a capacitor cover;

[0037] S3. The entire surface of the prepared capacitor cover substrate is coated with adhesive, and the adhesive is added and vulcanized at high temperature to cause a cross-linking reaction between the adhesive, the capacitor cover substrate and the capacitor cover rubber sealing surface, so that the capacitor cover substrate and the capacitor cover rubber sealing surface are well bonded together with high bonding strength. After a long-term test at a high temperature of 150 degrees, there is no separation between the capacitor cover substrate and the capacitor cover rubber sealing surface for 3000 hours;

[0038] S4. Wrap the rubber sealing surface of the capacitor cover plate with the capacitor cover plate substrate, and put the capacitor cover plate substrate and the rubber sealing surface of the capacitor cover plate into a vulcanizer for high-temperature molding through hot vulcanization.

[0039] In step S11 , the thermoplastic material may be one of PPA, PA66, PA6 and POK.

[0040] In step S3, the adhesive is phenolic resin.

[0041] The thermoplastic aluminum electrolytic capacitor sealing cover plate prepared by the present invention changes the single-sided sealing mode of the traditional sealing cover plate, and is designed with rubber seals on the bottom, edge, and terminal riveting holes to form an all-round sealing surface, thereby better solving the problem of premature failure of the aluminum electrolytic capacitor caused by capacity attenuation due to electrolyte loss caused by electrolyte leakage and volatilization of the aluminum electrolytic capacitor.

[0042] At the same time, the reasonable design of the new capacitor sealing cover makes the aluminum electrolytic capacitor have an excellent sealing effect and extends the service life of the aluminum capacitor. The new composite material capacitor sealing cover has reached the international advanced cover quality level after testing.

[0043] Moreover, after testing, the chloride ion, fluoride ion, bromide ion, nitrate ion and phosphate ion in the materials are all ≤1PPM, and the sulfate ion is ≤2PPM, which can fully meet the product requirements.

[0044] In summary, the localization of capacitor sealing cover plates has solved the problem of difficulty in purchasing domestic high-end aluminum electrolytic capacitor sealing cover plates.

[0045] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for manufacturing a sealing cover plate of a thermoplastic aluminum electrolytic capacitor, characterized in that: The method comprises the following steps: S1. preparing a capacitor cover substrate; S11, using thermoplastic material as the main material, and adding 10%-50% long glass fiber into the main material; S12, adding an auxiliary agent to the mixed material in step S11, and mixing the various materials in a mixer; S13, placing the uniformly mixed multiple materials in an injection molding machine and injection molding them into a capacitor cover substrate; S2. Prepare the rubber sealing surface of the capacitor cover; S21, using EPDM rubber and butyl rubber as raw materials and mixing them evenly; S22, placing the uniformly mixed EPDM rubber and butyl rubber in a calender and calendering them into a rubber sealing surface of a capacitor cover; S3, applying adhesive on the entire surface of the prepared capacitor cover substrate; S4. Wrap the rubber sealing surface of the capacitor cover plate with the capacitor cover plate substrate, and put the capacitor cover plate substrate and the rubber sealing surface of the capacitor cover plate into a vulcanizer for high-temperature molding through hot vulcanization.

2. The method for manufacturing a thermoplastic aluminum electrolytic capacitor sealing cover plate according to claim 1, characterized in that: In the step S11, the thermoplastic material may be one of PPA, PA66, PA6 and POK.

3. The method for manufacturing a thermoplastic aluminum electrolytic capacitor sealing cover plate according to claim 1, characterized in that: In the step S3, the adhesive is phenolic resin.