Structure for reducing stress of capacitor and improving vibration resistance and temperature shock resistance

Abstract

The utility model discloses a structure for reducing capacitor stress and improving vibration and temperature shock resistance, and belongs to the technical field of capacitor packaging. The capacitor comprises a shell, openings are formed in the left side and the right side of the shell, a containing core assembly is arranged in the shell and comprises a plurality of capacitor core bags, electrodes are arranged on the left side and the right side of the containing core assembly, pins extending outwards from the openings of the shell are formed on each electrode, and the vibration and temperature shock resisting structure comprises a plurality of inner hoops. The four capacitor core packages are arranged on the four faces of the capacitor core assembly in a surrounding and hooping mode at the gap position between every two adjacent capacitor core packages and are tightly combined with the shell. The capacitor has the advantages that the design is reasonable, the structure is reliable, the inner hoop is firmly installed, the main body structure and the manufacturing process of the capacitor do not need to be changed, stress is effectively dispersed by adding the inner hoop structure by utilizing internal gaps and gaps of the capacitor, and the temperature shock resistance and vibration shock resistance of the capacitor are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of capacitor packaging, and in particular relates to a structure for reducing capacitor stress and improving vibration resistance and temperature shock resistance. Background Art

[0002] With the continuous promotion and application of industrial technology, power electronic equipment is increasingly used in various industries. For example, converters have been widely used in transportation, power grids, medical and other fields. In order to improve the power density of the converter, increasing the operating frequency and voltage of the switching circuit is an effective method. Traditional electrolytic capacitors can no longer meet the needs of practical applications and have been gradually replaced by film capacitors. Taking the support capacitor in the converter as an example, it plays the role of energy storage, absorption and filtering, while the support capacitors in some high-power converters have problems such as large size, heavy weight and poor application environment conditions (such as vibration, force, thermal shock). In addition, weight reduction is an important goal to pursue in some special industries (such as transportation). The above problems undoubtedly put forward higher requirements for the capacitor structure.

[0003] like Figure 1 As shown, taking a metal shell supported capacitor as an example, it is mainly composed of a core group, inner leads, busbars, insulating materials, packaging materials (epoxy resin, etc.) and a shell, etc. Usually, the core group, inner leads, busbars, insulating materials, etc. are assembled into a whole and placed in the shell, and then the packaging materials are poured into the shell to make it a whole. Since the capacitor should meet its application requirements in a wet and hot environment, it is necessary not only to ensure that it can meet the mechanical performance requirements such as vibration resistance, but also the airtightness is also a key factor in ensuring its pressure resistance during its life cycle. Taking thermal stress as an example, the thermal expansion coefficient of the stainless steel metal shell is different from that of the epoxy resin, and since the thermal conductivity of the two materials is also inconsistent, whether it is heating up or cooling down, stress will be generated at the metal and epoxy interface, and this stress cannot be eliminated.

[0004] Furthermore, there are problems with low bonding strength between the potting material of the capacitor and the metal shell, and large differences in linear expansion coefficients. When the capacitor is powered on, the temperature of the shell is lower than the temperature inside before reaching thermal equilibrium. The inside of the capacitor continues to heat up, and the internal volume expands, causing the shell to expand and deform and bulge outward, affecting installation; when the capacitor loses power, the internal temperature of the capacitor cools down slowly, and the metal shell will be squeezed inward. After the capacitor is subjected to temperature shock and vibration shock, the potting material and the metal shell are easy to separate from each other. In addition, considering the capacitor manufacturing process, the assembly and packaging processes that can be carried out conveniently, safely and reliably also put forward requirements for the capacitor structure.

[0005] In view of the above-mentioned prior art, it is necessary to improve the structure of the existing capacitor. To this end, the applicant has made a useful design. The technical solution to be introduced below is produced in this context. Utility Model Content

[0006] The utility model aims to provide a structure which reduces capacitor stress and improves resistance to vibration and temperature shock, has a reliable structure and can effectively disperse stress.

[0007] The purpose of the utility model is achieved in this way. A structure for reducing capacitor stress and improving resistance to vibration and temperature shock is provided. The capacitor includes a shell with left and right sides formed as openings. A core assembly is arranged in the shell. The core assembly includes a plurality of capacitor core packages. Electrodes are arranged on the left and right sides of the core assembly. Each electrode is formed with a pin extending outward from the opening of the shell. The anti-vibration and temperature shock structure includes a plurality of inner hoops, which are respectively arranged on four surfaces of the core assembly at the gap position between two adjacent capacitor core packages and are tightly combined with the shell.

[0008] In a specific embodiment of the utility model, the inner hoop is formed by a pair of longitudinal beams parallel to each other and a pair of cross beams connected to the upper and lower ends of the pair of longitudinal beams, which are engaged with each other.

[0009] In another specific embodiment of the utility model, the longitudinal beam is bent and extended vertically at both ends to form a longitudinal beam bending section, and a longitudinal beam inclined section is formed at the free end of the longitudinal beam bending section; the cross beam is bent and extended obliquely at both ends to form a cross beam bending section, and a cross beam horizontal section is formed at the free end of the cross beam bending section, and a notch is formed at the end of the cross beam horizontal section. When the longitudinal beam and the cross beam are engaged, the longitudinal beam bending section is located below the cross beam horizontal section, the longitudinal beam inclined section is in contact with the cross beam bending section, and the longitudinal beam is snapped into the notch.

[0010] In yet another specific embodiment of the present invention, the pair of cross beams are fixedly connected to the inner wall of the outer shell.

[0011] In yet another specific embodiment of the present invention, the crossbeam is fixed to the inner wall of the outer shell by welding.

[0012] Due to the adoption of the above structure, the utility model has the following beneficial effects compared with the prior art: reasonable design, reliable structure, firm installation of the inner hoop, no need to change the main structure and manufacturing process of the capacitor, and utilizing the internal voids and gaps of the capacitor and adding the inner hoop structure to effectively disperse the stress and improve the ability of the capacitor to resist temperature shock and vibration shock. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall structure of the capacitor of the utility model;

[0014] Figure 2 It is a structural schematic diagram of the inner hoop described in the utility model.

[0015] In the figure: 1. shell; 2. capacitor core assembly, 21. capacitor core package; 3. electrode, 31. pin; 4. inner hoop, 41. longitudinal beam, 411. longitudinal beam bending section, 412. longitudinal beam inclined section, 42. cross beam, 421. cross beam bending section, 422. cross beam horizontal section, 4221. notch. DETAILED DESCRIPTION

[0016] The specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings, but the description of the embodiments is not a limitation of the technical solution. Any changes in form rather than substance based on the concept of the present invention should be regarded as the protection scope of the present invention.

[0017] In the following description, all concepts related to directionality (or orientation) such as up, down, left, right, front and back are referring to the position state of the figure being described, and are intended to facilitate public understanding. Therefore, they should not be understood as special limitations on the technical solutions provided by the present utility model.

[0018] See also Figure 1 The utility model relates to a structure for reducing stress of a capacitor and improving resistance to vibration and temperature shock. The capacitor comprises a cylindrical shell 1 with openings formed on the left and right sides, and a core assembly 2 is arranged in the shell 1. The core assembly 2 comprises a plurality of capacitor core packages 21, and electrodes 3 are arranged on the left and right sides of the core assembly 2. Each electrode 3 is formed with a pin 31 extending outward from the opening of the shell 1. The anti-vibration and temperature shock structure comprises a plurality of inner hoops 4, which are respectively arranged on the four surfaces of the core assembly 2 at the gap position between two adjacent capacitor core packages 21 and are tightly combined with the shell 1. In this embodiment, three capacitor core packages 21 are illustrated, and two inner hoops 4 are installed in two gaps of the three capacitor core packages 21. The utility model utilizes the internal gaps and voids of the capacitor, and improves the structure of the capacitor's resistance to temperature shock and vibration shock by adding inner hoops 4, effectively dispersing stress, thereby improving the capacitor's ability to resist temperature shock and vibration shock.

[0019] See also Figure 2The inner hoop 4 is formed by a pair of longitudinal beams 41 parallel to each other and a pair of cross beams 42 connected to the upper and lower ends of the pair of longitudinal beams 41. Specifically, the longitudinal beams 41 are bent vertically at both ends to form a longitudinal beam bending section 411, and a longitudinal beam inclined section 412 is formed at the free end of the longitudinal beam bending section 411, that is, the longitudinal beam bending section 411 and the longitudinal beam inclined section 412 cooperate to form an angle; the cross beam 42 is bent obliquely at both ends to form a cross beam bending section 421, and a cross beam horizontal section 422 is formed at the free end of the cross beam bending section 421, that is, an angle is formed between the cross beam bending section 421 and the cross beam horizontal section 422. A notch 4221 is formed at the end of the cross beam horizontal section 422. When the longitudinal beam 41 and the cross beam 42 are engaged, the longitudinal beam bending section 411 is located below the cross beam horizontal section 422, and the longitudinal beam inclined section 412 is in contact with the cross beam bending section 421, that is, the bending angle and the included angle match; and the longitudinal beam 41 is fixed with the notch 4221 by snapping, thereby ensuring the integrity of the inner hoop 4. The pair of cross beams 42 are fixedly connected to the inner wall of the outer shell 1 by welding or other methods.

Claims

1. A structure for reducing stress of a capacitor and improving resistance to vibration and temperature shock, the capacitor comprising a shell (1) with openings on the left and right sides, a core assembly (2) being arranged in the shell (1), the core assembly (2) comprising a plurality of capacitor core packages (21), electrodes (3) being arranged on the left and right sides of the core assembly (2), each electrode (3) being formed with a pin (31) extending outward from the opening of the shell (1), characterized in that: The anti-vibration and temperature shock structure comprises a plurality of inner hoops (4), which are respectively arranged around the gap between two adjacent capacitor core packages (21) on four surfaces of the capacitor core assembly (2) and are tightly combined with the outer shell (1).

2. The structure for reducing capacitor stress and improving resistance to vibration and temperature shock according to claim 1, characterized in that: The inner hoop (4) is formed by a pair of longitudinal beams (41) longitudinally parallel to each other and a pair of transverse beams (42) connected to the upper and lower ends of the pair of longitudinal beams (41) interlocking with each other.

3. A structure for reducing capacitor stress and improving resistance to vibration and temperature shock according to claim 2, characterized in that: The longitudinal beam (41) is bent vertically at both ends to extend to form a longitudinal beam bending section (411), and a longitudinal beam inclined section (412) is formed at the free end of the longitudinal beam bending section (411); the cross beam (42) is bent obliquely at both ends to extend to form a cross beam bending section (421), and a cross beam horizontal section (422) is formed at the free end of the cross beam bending section (421), and a notch (4221) is formed at the end of the cross beam horizontal section (422); when the longitudinal beam (41) and the cross beam (42) are engaged, the longitudinal beam bending section (411) is located below the cross beam horizontal section (422), the longitudinal beam inclined section (412) is in contact with the cross beam bending section (421), and the longitudinal beam (41) is engaged with the notch (4221).

4. The structure for reducing capacitor stress and improving resistance to vibration and temperature shock according to claim 2, characterized in that: The pair of cross beams (42) are fixedly connected to the inner wall of the outer shell (1).

5. The structure for reducing capacitor stress and improving resistance to vibration and temperature shock according to claim 4, characterized in that: The cross beam (42) is fixed to the inner wall of the outer shell (1) by welding.

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