Thickened concave-bottom aluminum shell for soldering lug aluminum electrolytic capacitor

Abstract

The utility model discloses a thickened concave-bottom aluminum shell for a soldering lug aluminum electrolytic capacitor in the field of soldering lug aluminum electrolytic capacitors, which comprises a cylindrical shell main body with an opening at the upper end and an annular thickened bottom shell integrally formed at the bottom end of the cylindrical shell main body, 30-degree oblique angle transition is adopted at the combination position of the center of the thickened bottom shell and the cylindrical shell body, a round anti-explosion groove is integrally formed in the position, located at the center, of the bottom of the thickened bottom shell, and a plurality of anti-explosion wire grooves corresponding to one another are evenly formed in the positions, located on the two faces of the anti-explosion groove, of the cylindrical shell body in the circumferential direction. And a plurality of reinforcing ribs are uniformly distributed and molded at the bottom in the cylindrical shell main body and on the back surface of the thickened bottom shell along the circumferential direction. According to the utility model, the thickness of the closed bottom is increased to 1.1-1.2 mm, the internal gas pressure of the capacitor can be effectively blocked, the expansion height of the bottom can be buffered in cooperation with the explosion-proof wire duct which is concave inwards by 0.5 mm, and the occurrence rate of bottom heaving under the high-temperature storage working condition of 105 DEG C is reduced by more than 90% according to actual measurement.

Description

TECHNICAL FIELD

[0001] The utility model relates to a welding sheet aluminum electrolytic capacitor field, concretely is a kind of thickened concave bottom aluminum shell for welding sheet aluminum electrolytic capacitor. BACKGROUND

[0002] With the development of electronic equipment to miniaturization, high power density direction, the application demand of "miniaturization+large ripple" of welding sheet aluminum electrolytic capacitor is increasing day by day.At present, the thickness of the aluminum shell bottom of conventional welding sheet aluminum electrolytic capacitor is only 0.65mm, and the bottom explosion-proof groove is flush with the aluminum shell bottom, and the explosion-proof pressure is only 0.5-1.4MPa.

[0003] In actual application and life verification process, the above-mentioned conventional aluminum shell has obvious defects: on the one hand, the electrolyte in the capacitor is easy to decompose to produce gas under the action of high temperature (such as 105℃) or large ripple current, which leads to the increase of internal pressure, and the relatively thin bottom cannot effectively block the pressure, and the "bottom drum" phenomenon is easy to appear;On the other hand, the lower explosion-proof pressure makes the explosion-proof valve open when the internal gas pressure is slightly high, which not only shortens the service life of the capacitor, but also may lead to electrolyte leakage, which affects the reliability of the equipment;In addition, the flush bottom explosion-proof groove cannot buffer the bulging deformation, which further aggravates the bottom drum problem.

[0004] There is no integrated structure optimization scheme for the above-mentioned pain points in the prior art, which cannot meet the customer's demand for welding sheet aluminum electrolytic capacitor "high-temperature storage bottom drum improvement" "long life under large capacity" (such as 2000 hours at 105℃).Therefore, the technical personnel in the art provide a thickened concave bottom aluminum shell for welding sheet aluminum electrolytic capacitor to solve the problems raised in the above background art. CONTENT OF UTILITY MODEL

[0005] The utility model aims at providing a thickened concave bottom aluminum shell for welding sheet aluminum electrolytic capacitor to solve the problems raised in the above background art.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical scheme:

[0007] A thickened concave bottom aluminum shell for welding sheet aluminum electrolytic capacitor, comprising a cylindrical shell body with an open upper end and a ring-shaped thickened bottom shell integrally formed at the bottom end of the cylindrical shell body, the center part of the thickened bottom shell is transitioned with the cylindrical shell body at an angle of 30 degrees, and a circular explosion-proof groove is integrally formed at the center part of the bottom of the thickened bottom shell, a plurality of explosion-proof grooves corresponding to each other are uniformly distributed along the circumference on both sides of the cylindrical shell body at the position of the explosion-proof groove, and a plurality of reinforcing ribs are uniformly distributed and formed along the circumferential direction on the inner bottom of the cylindrical shell body at the back of the thickened bottom shell.

[0008] The thickness of the inner wall and the bottom of the cylindrical shell body is 0.6-0.7mm; the thickness of the thickened bottom shell is 0.5mm, ensuring that the thickness reaches 1.1-1.2mm after the thickened bottom shell is combined with the bottom of the cylindrical shell body, and the explosion-proof pressure of the thickened bottom shell is 1.4-2.0Mpa; the depth of the explosion-proof groove is 0.5mm.

[0009] As a further scheme of the utility model: the outer diameter of the cylindrical shell body is 34.9-35.1mm, and the inner diameter is 34.0-34.2mm, and the total height of the cylindrical shell body is 54.2-54.4mm.

[0010] The material of the cylindrical shell body and the thickened bottom shell is aluminum alloy, and meets the ROHS2.0 environmental protection standard.

[0011] The cylindrical shell body is suitable for welding sheet aluminum electrolytic capacitor.

[0012] The diameter of the bottom of the circular explosion-proof groove is 15mm.

[0013] Compared with the prior art, the utility model has the beneficial effects that:

[0014] 1. Bottom drum phenomenon is significantly improved: the thickness of the closed bottom is increased to 1.1-1.2mm, which can effectively block the internal gas pressure of the capacitor, and cooperate with the 0.5mm deep explosion-proof groove to buffer the bottom bulging height, and the actual measurement shows that the bottom drum occurrence rate is reduced by more than 90% under the 105℃ high-temperature storage working condition;

[0015] 2. Life is greatly prolonged: the explosion-proof pressure is increased to 1.4-2.0MPa, which avoids the false triggering of the explosion-proof valve under low pressure, and the anti-deformation ability of the thickened bottom makes the welding sheet aluminum electrolytic capacitor have a service life of 2000 hours under the working condition of 105℃, V n , I an and larger capacity, which meets the customer's demand for high reliability;

[0016] 3. Strong adaptability: the shell size (outer diameter 34.9-35.1mm, total height 54.2-54.4mm) and assembly precision (perpendicularity ≤0.15mm) adapt to the installation requirements of small-sized welding sheet aluminum electrolytic capacitor, and the existing capacitor production line does not need to be changed to be compatible with use;

[0017] 4. Compliance and market competitiveness: the environmentally friendly aluminum alloy material meets the ROHS2.0 standard and meets the global environmental protection regulations; at the same time, the product can realize annual sales of more than 2 million, helping enterprises to seize the market commanding point of small-sized + long-life welding sheet aluminum electrolytic capacitor;

[0018] 5. Stable and reliable structure: the integrated shell body and the closed bottom, precise size control, ensure the overall structural strength of the aluminum shell, avoid cracking and deformation during assembly or use. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a half cut structure schematic view of the utility model;

[0020] Figure 2 It is the utility model Figure 1 The local enlarged view of A in the middle.

[0021] Figure 3 It is the bottom view of the utility model;

[0022] Figure 4 It is the size drawing of the bottom structure of the utility model.

[0023] In the drawing: 1, cylindrical shell body; 2, explosion-proof groove; 3, explosion-proof wire groove; 4, thickened bottom shell; 5, reinforcing rib. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the utility model.

[0025] Please refer to Figures 1 to 4 In the embodiments of the utility model, a thickened concave bottom aluminum shell for welding piece aluminum electrolytic capacitor includes a cylindrical shell body 1 with an open upper end and a ring-shaped thickened bottom shell 4 integrally formed at the bottom end of the cylindrical shell body 1. The center part of the thickened bottom shell 4 is transitioned with the cylindrical shell body 1 at a 30-degree angle, and a circular explosion-proof groove 2 is integrally formed at the center part of the bottom of the thickened bottom shell 4. The two sides of the cylindrical shell body 1 at the explosion-proof groove 2 part are both provided with a plurality of corresponding explosion-proof wire grooves 3 distributed along the circumference. A plurality of reinforcing ribs 5 are formed along the circumferential direction and distributed along the circumference on the inner bottom of the cylindrical shell body 1 at the back of the thickened bottom shell 4.

[0026] As Figure 4 shown, the thickness of the inner wall of the cylindrical shell body 1 and the bottom is 0.6-0.7mm; the thickness of the thickened bottom shell 4 is 0.5mm, ensuring that the thickness of the thickened bottom shell and the bottom of the cylindrical shell body 1 reaches 1.1-1.2mm after being combined, and the explosion-proof pressure of the thickened bottom shell 4 is 1.4-2.0Mpa; the depth of the explosion-proof groove is 0.5mm, and the explosion-proof wire groove is shortened by 7mm.

[0027] By adopting the technical scheme, the original aluminum shell bottom thickness of 0.65 mm is increased by 0.5 mm to reach 1.15 mm, the explosion-proof pressure is changed from 0.5-1.4 Mpa to 1.4-2.0 Mpa, and meanwhile, the aluminum shell bottom explosion-proof groove position is changed from the original bottom flush to an inner recess of 0.5 mm. The thickened aluminum shell bottom can well block the internal gas pressure, the improved explosion-proof pressure can effectively alleviate the disadvantage that the internal low gas pressure can easily cause the explosion-proof valve to open, and the aluminum shell bottom explosion-proof groove made into an inner recess of 0.5 mm can reduce the height of the aluminum shell bottom bulging caused by the internal pressure, and plays a buffering role.

[0028] The outer diameter of the cylindrical shell body 1 is 34.9-35.1 mm, the inner diameter is 34.0-34.2 mm, and the total height of the cylindrical shell body 1 is 54.2-54.4 mm.

[0029] The material of the cylindrical shell body 1 and the thickened bottom shell 4 is aluminum alloy, and meets the ROHS 2.0 environmental protection standard.

[0030] The cylindrical shell body 1 is suitable for a welding sheet aluminum electrolytic capacitor, and the bottom diameter of the circular explosion-proof groove is 15 mm.

[0031] Preparation and assembly process:

[0032] Aluminum shell preparation: the shell body and the closed bottom are integrally made by adopting aluminum alloy sheet through a stretching forming process. After forming, the annular explosion-proof groove 2 is recessed by 0.5 mm and the 30-degree bevel transition is made by numerical control machining. At the same time, the corresponding explosion-proof line groove 3 is opened on the inner and outer sides of the bottom. Finally, surface treatment such as passivation is carried out to improve corrosion resistance.

[0033] Performance detection: the size of the aluminum shell, such as outer diameter, bottom thickness, total height, explosion-proof pressure, perpendicularity, and ROHS 2.0 compliance are detected according to the inspection report standard to ensure that all parameters meet the specifications.

[0034] Capacitor assembly: the aluminum shell, capacitor core, electrolyte, cover plate, welding sheet pin and other components are assembled to form a welding sheet aluminum electrolytic capacitor after sealing. The size accuracy of the aluminum shell during the assembly process can ensure the fit of the components without assembly gap.

[0035] (Three) verification of use effect

[0036] The welding sheet aluminum electrolytic capacitor with the aluminum shell of the utility model, model K350543DA750A, is placed in a 105℃ environment, and the life test is carried out according to the rated voltage V n , and the rated ripple current I an .

[0037] After 2000 hours of testing, the capacitor capacity change rate ΔC / C0 is -8% satisfying -15%≤ΔC / C0≤15%, the loss angle tangent DF is 32% satisfying DF≤40%, the leakage current I leak is 3500uA / 5min satisfying I leak ≤5000uA / 5min.

[0038] During the test, there is no any bottom drum phenomenon, and the explosion-proof valve is not triggered by mistake, which verifies the effectiveness of the aluminum shell in improving the bottom drum and prolonging the service life.

[0039] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this, any skilled person in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A thickened concave bottom aluminum shell for a tab aluminum electrolytic capacitor, comprising a cylindrical shell body (1) with an open upper end and a ring-shaped thickened bottom shell (4) integrally formed at the bottom end of the cylindrical shell body (1), characterized in that: The thickened bottom shell (4) is combined with the cylindrical shell body (1) at the center part with a 30-degree bevel transition, and the bottom of the thickened bottom shell (4) is integrally formed with a circular explosion-proof groove (2) at the center part, the cylindrical shell body (1) is provided with a plurality of corresponding explosion-proof line grooves (3) on both sides of the explosion-proof groove (2) part along the circumference, and a plurality of reinforcing ribs (5) are formed on the inner bottom of the cylindrical shell body (1) along the circumferential direction and are circumferentially distributed on the back of the thickened bottom shell (4); The thickness of the inner wall and the bottom of the cylindrical shell body (1) is 0.6-0.7mm; the thickness of the thickened bottom shell (4) is 0.5mm, ensuring that the thickness of the thickened bottom shell and the bottom of the cylindrical shell body (1) reaches 1.1-1.2mm after being combined, the explosion-proof pressure of the thickened bottom shell (4) is 1.4-2.0Mpa; the depth of the explosion-proof groove is 0.5mm.

2. The thickened concave bottom aluminum shell for a tab aluminum electrolytic capacitor according to claim 1, wherein: The outer diameter of the cylindrical shell body (1) is 34.9-35.1mm, the inner diameter is 34.0-34.2mm, and the total height of the cylindrical shell body (1) is 54.2-54.4mm.

Images