A metal bracket capacitor and its assembly welding method

Abstract

The present invention provides an assembly welding method for a metal bracket capacitor, comprising the following steps: A. A plurality of solder joint groups are longitudinally spaced apart on the outside of the metal bracket, the solder joint groups include two solder joint grooves spaced apart, and the solder joint grooves provide corresponding convex points on the inside of the metal bracket; B. A solder coating is provided on the inside of the metal bracket and on the ends of each ceramic capacitor chip, and a solder paste layer is provided between the metal bracket and the ends of the ceramic capacitor chip; C. Two lead-out electrodes of the resistance welding are lightly pressed to contact the two solder joint grooves of each solder joint group, respectively, so that the two lead-out electrodes are respectively connected to the two solder joint grooves to form a closed welding current loop. The present invention also provides a metal bracket capacitor. The present invention achieves a local welding effect between the metal bracket and the ceramic capacitor chip, ensures the integrity of the pin solder layer, does not need to re-electroplate the pin, and simplifies the process steps.

Description

Technical Field

[0001] The invention relates to a metal bracket capacitor and an assembling and welding method thereof. Background Art

[0002] With the development of science and technology, the demand for large-capacity and high-power capacitors in fields such as power supply, industry, automobile, military industry and aerospace is increasing, and traditional chip ceramic capacitors are difficult to meet the demand for large capacity. Therefore, multiple ceramic capacitors are assembled in parallel to meet the demand for large-capacity capacitors. Metal bracket capacitors came into being.

[0003] Currently, the main assembly welding method for metal bracket capacitors is reflow soldering. This welding method requires the product to be heated as a whole, causing the surface coating of the metal bracket to melt due to the heat, affecting the solderability of the coating on the pins of the metal bracket. Therefore, after the assembly welding is completed, in order to ensure the solderability of the pins, the pins of the metal bracket must be electroplated again, resulting in a cumbersome process. Summary of the invention

[0004] The purpose of the present invention is to address the deficiencies of the prior art and propose a metal bracket capacitor and an assembly welding method thereof, so as to achieve a local welding effect between the metal bracket and the ceramic capacitor chip, ensure the integrity of the pin welding layer, eliminate the need for re-electroplating the pins, and simplify the process steps.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for assembling and welding a metal bracket capacitor, wherein the metal bracket capacitor comprises two metal brackets and a plurality of ceramic capacitor chips stacked between the two metal brackets, comprising the following steps:

[0007] A. Multiple solder joint groups are arranged at intervals on the outside of the metal bracket, and each end of each ceramic capacitor chip corresponds to at least one solder joint group. The solder joint group includes two solder joint grooves arranged at intervals, and the solder joint grooves provide corresponding convex points on the inside of the metal bracket;

[0008] B. A solder coating is provided on the inner side of the metal bracket and the end of each ceramic capacitor chip, and a solder paste layer is provided between the metal bracket and the end of the ceramic capacitor chip;

[0009] C. Lightly press the two lead-out electrodes of the resistance welding to contact the two solder joint grooves of each solder joint group, so that the two lead-out electrodes are respectively connected to the two solder joint grooves to form a closed welding current loop. The area on the metal bracket through which the welding current flows is locally heated until the corresponding solder paste in the area melts. After the solder paste melts, a mixed solder joint is formed with the metal bracket and the welding coating of the ceramic capacitor chip.

[0010] Furthermore, in step C, each welding point group can be welded simultaneously.

[0011] Furthermore, the metal bracket includes a vertical plate, a supporting foot arranged at the lower section of the vertical plate and extending inward, and a pin arranged at the lower end of the vertical plate, the ceramic capacitor chip at the lower end is placed on the supporting foot, and the welding point group is arranged on the vertical plate.

[0012] Furthermore, the two welding point grooves of each welding point group are arranged horizontally at intervals.

[0013] Furthermore, the bumps are in contact with the corresponding ends of the ceramic capacitor chips.

[0014] The present invention is also achieved through the following technical solutions:

[0015] A metal bracket capacitor comprises two metal brackets, a plurality of ceramic capacitor chips stacked between the two metal brackets, a plurality of solder joint groups spaced apart on the outside of the metal brackets, and a solder paste layer spaced apart between the metal brackets and the ceramic capacitor chips, wherein at least one solder joint group corresponds to each of the two ends of each ceramic capacitor chip, and the solder joint group comprises two solder joint grooves spaced apart, and the solder joint grooves provide corresponding convex points on the inner side of the metal brackets, and the convex points are embedded in the solder paste layer.

[0016] Furthermore, the metal bracket includes a vertical plate, a supporting foot arranged at the lower section of the vertical plate and extending inward, and a pin arranged at the lower end of the vertical plate, the ceramic capacitor chip at the lower end is placed on the supporting foot, and the welding point group is arranged on the vertical plate.

[0017] Furthermore, the two welding point grooves of each welding point group are arranged horizontally at intervals.

[0018] Furthermore, the vertical plate, the supporting feet and the pins are integrally formed.

[0019] The present invention has the following beneficial effects:

[0020] 1. The present invention has a plurality of solder joint groups arranged at intervals on the outside of the metal bracket in the longitudinal direction, each solder joint group includes two solder joint grooves arranged at intervals. During assembly welding, the two lead-out electrodes of the resistance welding are lightly pressed and contacted respectively, so that the two lead-out electrodes are respectively connected to the two solder joint grooves to form a closed welding current loop. The area through which the welding current flows on the metal bracket is locally heated until the solder paste corresponding to the area is melted. After the solder paste melts, it forms a mixed solder joint with the metal bracket and the welding coating of the ceramic capacitor chip. The mixed solder joint welds the convex points formed by the ceramic capacitor chip, the metal bracket and the solder joint grooves together, thereby increasing the bonding strength between the metal bracket and the solder joint, and also ensuring the integrity of the pin solder layer. There is no need to electroplate the pin again after the assembly welding is completed, thereby simplifying the process steps. During the welding process, the convex point contacts the capacitor chip, and a space for storing a high-temperature solder paste layer is supported between the metal bracket and the ceramic capacitor chip. When using the product, customers may need to perform reflow soldering. The stored high-temperature solder paste layer can prevent the ceramic capacitor chip from falling off the metal bracket at increasingly higher reflow soldering temperatures, thereby avoiding the risk of the metal bracket capacitor falling apart.

[0021] 2. The supporting feet support the ceramic capacitor chip to facilitate the smooth resistance welding.

[0022] 3. During the welding process, the process parameters of each welding point group can be adjusted individually in real time through resistance welding, and all welding point groups can be welded at the same time. The operation is simple and convenient, which can improve the welding efficiency and is suitable for the rapid production of large quantities of products. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention is further described in detail below with reference to the accompanying drawings.

[0024] Figure 1 It is a schematic diagram of the structure of the metal bracket capacitor of the present invention.

[0025] Figure 2 It is a schematic diagram of the structure of the metal bracket of the present invention.

[0026] Among them, 1. Metal bracket; 11. Vertical plate; 12. Support feet; 13. Pins; 2. Ceramic capacitor chip; 3. Solder point groove; 4. Bump; 5. Solder paste layer. DETAILED DESCRIPTION

[0027] like Figure 1 and Figure 2As shown, the metal bracket capacitor includes two metal brackets 1, a plurality of ceramic capacitor chips 2 stacked between the two metal brackets 1, a plurality of solder joint groups spaced apart on the outside of the metal bracket 1, and a solder paste layer 5 spaced apart between the metal bracket 1 and each ceramic capacitor chip 2, each ceramic capacitor chip 2 has at least one solder joint group at both ends, and the solder joint group includes two solder joint grooves 3 spaced apart horizontally, and the solder joint grooves 3 provide corresponding bumps 4 on the inner side of the metal bracket 1, and the bumps 4 are embedded in the solder paste layer 5.

[0028] The metal bracket 1 includes a vertical plate 11, a supporting foot 12 provided at the lower section of the vertical plate 11 and extending inward, and a pin 13 provided at the lower end of the vertical plate 11, the ceramic capacitor chip 2 at the lower end is placed on the supporting foot 12, and the solder joint group is provided on the vertical plate 11. The vertical plate 11, the supporting foot 12 and the pin 13 are integrally formed.

[0029] The assembly welding method of the metal bracket capacitor includes the following steps:

[0030] A. Multiple solder joint groups are arranged at intervals in the longitudinal direction on the outside of the metal bracket 1. Each of the two ends of each ceramic capacitor chip 2 corresponds to at least one solder joint group. The solder joint group includes two solder joint grooves 3 arranged at intervals in the horizontal direction. The solder joint grooves 3 provide corresponding convex points 4 on the inside of the metal bracket 1. The convex points 4 are in contact with the ends of the ceramic capacitor chip 2.

[0031] B. A soldering layer is provided on the inner side of the metal bracket 1 and the end of each ceramic capacitor chip 2, and a solder paste layer 5 is provided between the metal bracket 1 and the end of the ceramic capacitor chip 2;

[0032] C. The two lead-out electrodes of the resistance welding are lightly pressed to contact the two soldering point grooves 3 of each soldering point group, so that the two lead-out electrodes are respectively connected to the two soldering point grooves 3 to form a closed welding current loop. The area where the welding current flows through the metal bracket 1 is locally heated until the solder paste corresponding to the area is melted. After the solder paste is melted, it forms a mixed solder joint with the solder coating of the metal bracket 1 and the ceramic capacitor chip 2;

[0033] In this step, each welding point group may be welded sequentially, or all welding point groups may be welded simultaneously.

[0034] The above description is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of implementation of the present invention. That is, equivalent changes and modifications made according to the scope of the patent application of the present invention and the contents of the specification should still fall within the scope covered by the patent of the present invention.

Claims

1. A method for assembling and welding a metal bracket capacitor, wherein the metal bracket capacitor comprises two metal brackets and a plurality of ceramic capacitor chips stacked between the two metal brackets, characterized in that: The steps include: Step A, a plurality of solder joint groups are longitudinally spaced apart on the outside of the metal bracket, and each of the two ends of each ceramic capacitor chip corresponds to at least one solder joint group, and the solder joint group includes two solder joint grooves spaced apart, and the solder joint grooves enable the inner side of the metal bracket to have corresponding convex points; Step B, providing a welding coating on the inner side of the metal bracket and the ends of each ceramic capacitor chip, and providing a solder paste layer between the metal bracket and the ends of the ceramic capacitor chip; Step C, lightly press the two lead-out electrodes of the resistance welding to contact the two soldering point grooves of each soldering point group, so that the two lead-out electrodes are respectively connected to the two soldering point grooves to form a closed welding current loop, and the area on the metal bracket through which the welding current flows is locally heated until the solder paste corresponding to the area is melted, and the solder paste after melting forms a mixed solder joint with the metal bracket and the solder coating of the ceramic capacitor chip; The convex point is in contact with the corresponding end of the ceramic capacitor chip; In step C, each welding point group may be welded simultaneously; The metal bracket includes a vertical plate, a supporting foot arranged at the lower section of the vertical plate and extending inward, and a pin arranged at the lower end of the vertical plate, the ceramic capacitor chip at the lower end is placed on the supporting foot, and the welding point group is arranged on the vertical plate; The two welding point grooves of each welding point group are arranged horizontally and spaced apart.

2. A metal bracket capacitor prepared by the assembly welding method according to claim 1, characterized in that: It includes two metal brackets, a plurality of ceramic capacitor chips stacked between the two metal brackets, a plurality of solder joint groups spaced apart on the outside of the metal brackets, and a solder paste layer spaced apart between the metal brackets and the ceramic capacitor chips. Each of the two ends of the ceramic capacitor chip corresponds to at least one solder joint group. The solder joint group includes two solder joint grooves spaced apart. The solder joint grooves provide corresponding convex points on the inner side of the metal brackets, and the convex points are embedded in the solder paste layer.

3. A metal bracket capacitor according to claim 2, characterized in that: The metal bracket includes a vertical plate, a supporting foot arranged at the lower section of the vertical plate and extending inward, and a pin arranged at the lower end of the vertical plate, the ceramic capacitor chip at the lower end is placed on the supporting foot, and the welding point group is arranged on the vertical plate.

4. The metal bracket capacitor according to claim 3, characterized in that: The vertical plate, the supporting feet and the pins are integrally formed.

Images