JP2024022783A - Capacitor and capacitor manufacturing method - Google Patents

Abstract

The present invention provides a capacitor that is easy to manufacture and can ensure insulation of external connections while obtaining a desired inductance reduction effect. [Solution] An assembly 3 in which a capacitor element 2, a positive electrode plate 4 and a negative electrode plate 5 connected to the capacitor element 2 are integrally molded with resin, and an exterior case 6 is formed by being connected to the assembly 3. The case main body 61 and the filling resin 7 filled in the outer case 6 are provided, and the positive electrode plate 4 and the negative electrode plate 5 are provided with extension parts 4c2 and 5c2 that are pulled out of the outer case 6, and the positive electrode plate 4 and the extending portion 5c2 of the negative electrode plate 5 are closely opposed to each other. It includes an intervening part 31a interposed between the parts 4c2 and 5c2, and a partial component part 31c that is connected to the case body 61 and constitutes a part of the exterior case 6. [Selection diagram] Figure 4

Description

The present invention relates to a capacitor in which a capacitor element and an electrode plate are housed in an outer case and the capacitor element is sealed by filling the outer case with resin, and in particular, an external connection portion pulled out from the outer case for connection to external equipment. The present invention relates to a capacitor comprising:

In recent resin-sealed capacitors, it has become mainstream to have the positive and negative electrode plates closely facing each other in order to reduce inductance, and it is also common practice to have the positive and negative electrode plates facing each other closely for the external connection parts pulled out outside the case. It is being said.

Japanese Patent Application Publication No. 2021-158844 Japanese Patent Application Publication No. 2015-149805

In order to obtain the desired inductance reduction effect, it is necessary to attach the positive and negative electrode plates with high precision. However, this requires the installation of a positioning jig to secure the positive and negative electrode plates before resin filling, which takes time and effort to assemble. Further, in order to ensure insulation between the external connection parts drawn out from the resin, a separate operation such as sandwiching an insulator such as insulating paper between the parts is required. Furthermore, if conductive parts are placed around an external connection part, it is necessary to ensure insulation between the external connection part and that part, but even if insulation is ensured by providing a sufficient insulation distance, , the entire device in which the capacitor is incorporated becomes large.

An object of the present invention is to provide a capacitor that is easy to manufacture and can ensure insulation of external connections while obtaining a desired inductance reduction effect.

The capacitor of the present invention includes a capacitor element 2, an assembly 3 in which a positive electrode plate 4 and a negative electrode plate 5 connected to the capacitor element 2 are integrally molded with resin, and an exterior case 6 that is connected to the assembly 3. The positive electrode plate 4 and the negative electrode plate 5 are provided with extending portions 4c2 and 5c2 that are drawn out of the external case 6, and the positive electrode The extended portion 4c2 of the electrode plate 4 and the extended portion 5c2 of the negative electrode plate 5 are close to each other and face each other. , an intervening part 31a interposed between the extending parts 4c2 and 5c2, and a partial component part 31c that is connected to the case body 61 and constitutes a part of the exterior case 6. In addition, "the positive electrode plate 4 and the negative electrode plate 5 are integrally molded with resin" means that the positive electrode plate and the negative electrode plate are integrally molded with resin, and the positive and negative electrode plates and the negative electrode plate are It does not mean that it is manufactured from resin.

In addition, in the capacitor manufacturing method of the present invention, the positive electrode plate 4 and the negative electrode plate 5 are set in a mold in a state in which they closely face each other, and the assembly 3 is manufactured by resin casting, and the assembly 3 and the case are It is characterized in that it is connected to a main body 61 to form an exterior case 6, and a filling resin 7 is filled in the exterior case 6 and hardened.

In the capacitor of the present invention, since the extended portion of the positive electrode plate and the extended portion of the negative electrode plate are close to each other and face each other, it is possible to achieve low inductance. In addition, since the positive electrode plate and the negative electrode plate are integrally molded with resin in advance and the distance between the positive electrode plate and the negative electrode plate is fixed, it is not necessary to use a separate positioning jig to attach the positive and negative electrode plates. Therefore, the assembly work is simple and the desired low inductance reduction effect can be obtained. Furthermore, since the assembly includes a partial component that constitutes a part of the exterior case, the positive and negative electrode plates can be positioned relative to the case by attaching the assembly to the case body that constitutes other parts of the exterior case. Therefore, no positioning jig is required, and assembly work is simple. Furthermore, since the outer periphery of the extended portion is covered in advance with the covering portion, it is possible to arrange conductive parts close to the extended portion, and the entire device in which the capacitor is incorporated can be miniaturized. Furthermore, since the intervening portion is interposed between the extending portions, there is no need to separately insert an insulating member such as insulating paper between the extending portions, and manufacturing is simple.

FIG. 1 is an exploded perspective view of a capacitor according to an embodiment of the invention. FIG. 2A is a perspective view of the positive electrode plate, and FIG. 2B is a perspective view of the negative electrode plate. FIG. 3 is a perspective view of a capacitor. FIG. 3 is an end view of the capacitor.

Next, one embodiment of the capacitor of the present invention will be described in detail based on the drawings. As shown in FIGS. 1 to 4, this capacitor includes a capacitor element 2, an assembly 3 in which a positive electrode plate 4 and a negative electrode plate 5 connected to the capacitor element 2 are integrally molded with resin, and the assembly 3 is connected to the capacitor element 2. It includes a case body 61 that forms an exterior case 6 by being filled, and a filling resin 7 that is filled into the exterior case 6. The above-mentioned parts will be explained below, but the concepts of "top and bottom," "left and right," and "front and rear" are used when filling the resin 7 into the exterior case 6, and are not necessarily "top and bottom" and "left and right" during use. It does not specify "before or after".

The capacitor element 2 is, for example, a film capacitor formed by winding a metallized film in which metal is deposited on an insulating film, and as shown in FIG. 1, electrode parts 2a and 2b are provided at both ends in the axial direction. ing. This capacitor element 2 has a barrel shape when viewed from the axial direction, specifically, R is provided at the four corners, and has a flat part 2c and a curved part 2d on the outer circumferential surface in the axial direction. There is. In FIG. 1, three DC capacitors 21 and two Y capacitors 22 are provided. The DC capacitors 21 are arranged with their flat parts 2c facing each other, and the Y capacitors 22 are arranged on the left side of the DC capacitor 21 with their flat parts 2c facing each other, staggered in a flying geese pattern. . The capacitor element 2 and the positive electrode plate 4 and the negative electrode plate 5 are connected via lead wires 23. Note that a laminated film capacitor may be used as the film capacitor. Further, the capacitor element 2 is not limited to a film capacitor, and various capacitor elements such as a ceramic capacitor and an electrolytic capacitor may be used.

The assembly 3 is formed by integrally molding a positive electrode plate 4 and a negative electrode plate 5 with resin. The resin part 31 of the assembly 3 has an intervening part 31a (see FIG. 4) interposed between the positive and negative electrode plates 4 and 5 that are close to each other and face each other (superimposed with a distance apart); It includes a covering portion 31b for covering, and a partial component portion 31c that is connected to the case body 61 and constitutes a part of the outer case 6.

As shown in FIG. 4, the intervening portion 31a is interposed between the substrate portions 4a and 5a and between the extending portions 4c2 and 5c2 of the positive and negative electrode plates 4 and 5, which will be described later. Specifically, between the substrate portion 4a of the positive electrode plate 4 and the substrate portion 5a of the negative electrode plate 5, which are close to each other, and between the extended portion 4c2 of the positive electrode plate 4 and the negative electrode plate 5, which are also close to each other and opposite to each other. It is interposed between the portion 5c2 and the portion 5c2. However, since the inside of the partial component part 31c is filled with the filling resin 7, the extending part located inside the substrate parts 4a, 5a and the partial component part 31c (inside the side wall part 6b indicated by the dotted line in FIG. 4) The intervening portion 31a does not necessarily need to be provided between 4c2 and 5c2.

The covering portion 31b covers the substrate portions 4a and 5a of the positive and negative electrode plates 4 and 5 and the extending portions 4c2 and 5c2. Specifically, the outer periphery of the substrate portion 4a of the positive electrode plate 4 and the substrate portion 5a of the negative electrode plate 5 which are closely opposed to each other, and the extended portion 4c2 of the positive electrode plate 4 and the outer circumference of the negative electrode plate 5 which are also closely opposed to each other. The outer periphery of the extended portion 5c2 is covered. However, since the inside of the partial structure part 31c is filled with the filling resin 7, it is not necessarily necessary to cover the substrate parts 4a, 5a and the extension parts 4c2, 5c2 located inside the partial structure part 31c. Element connecting parts 4b and 5b and terminal parts 4c1 and 5c1, which will be described later, of the positive and negative electrode plates 4 and 5 are not covered because they are provided for connection with the capacitor element 2 and external equipment.

By the way, the exterior case 6 includes a bottom portion 6a that is substantially rectangular in plan view, and side wall portions 6b rising upward from each of the four sides of the bottom portion 6a, and is used to accommodate the capacitor element 2 and the positive and negative electrode plates 4 and 5 inside. A housing portion 6d is formed. The upper end of the side wall portion 6b is an opening 6c.

The partial component portion 31c constitutes the upper side of the side wall portion 6b, and has a substantially rectangular cylindrical shape as shown in FIG. A connecting portion 31c1 for connecting to the upper end of the case body 61 is provided at the lower end. Specifically, the outer circumferential surface is retreated inward. The upper end of the case body 61 has an inner circumferential surface retracted outward as a connected portion 61a, so that the partial component portion 31c can be fitted (internally fitted) into the case body 61. A plurality of holes 32 are formed inside the partial component portion 31c. This hole 32 functions as a filling hole when filling the filling resin 7 and as an escape hole for letting air in the outer case 6 escape. A plurality of mounting legs 33 for attaching the capacitor 1 to an external device or the like are provided near the upper end of the partial component portion 31c.

The positive electrode plate 4 is made of a metal plate such as aluminum or copper. As shown in FIG. 2A, it includes a substrate section 4a, an element connection section 4b extending from the substrate section 4a, and an external connection section 4c also extending from the substrate section 4a. The substrate portion 4a mainly faces the side surface of the capacitor element 2. This board portion 4a is located inside the partial component portion 31c of the exterior case 6. The element connection portion 4b extends from the outer peripheral edge of the substrate portion 4a. This element connection part 4b is for connecting to one electrode part 2a of the capacitor element 2, and is located above the one electrode part 2a of the capacitor element 2. Further, an insertion hole 4b1 for passing the lead wire 23 is provided. The external connection portion 4c extends from the outer peripheral edge of the substrate portion 4a. It is pulled out from inside the partial component part 31c of the exterior case 6 for connection with external equipment. That is, it is pulled out of the exterior case 6. The external connection portion 4c includes a terminal portion 4c1 that contacts and is connected to the external connection portion 4c, and an extension portion 4c2 that connects the terminal portion 4c1 and the substrate portion 4a.

The negative electrode plate 5 is made of a metal plate such as aluminum or copper. As shown in FIG. 2B, it includes a substrate portion 5a, an element connection portion 5b extending from the substrate portion 5a, and an external connection portion 5c also extending from the substrate portion 5a, and is basically substantially the same as the positive electrode plate 4. It is the shape. The substrate portion 5a mainly faces the side surface of the capacitor element 2. Further, it is closely opposed to the substrate portion 4a of the positive electrode plate 4. This board portion 5a is located inside the outer case 6. The element connection portion 5b extends from the outer peripheral edge of the substrate portion 5a. This element connection part 5b is for connecting to the other electrode part 2b of the capacitor element 2, and is located above the other electrode part 2b of the capacitor element 2. Further, an insertion hole 5b1 for passing the lead wire 23 is provided. The external connection portion 5c extends from the outer peripheral edge of the substrate portion 5a. It is pulled out from inside the partial component part 31c of the exterior case 6 for connection with external equipment. That is, it is pulled out of the exterior case 6. The external connection portion 5c includes a terminal portion 5c1 that contacts and is connected to the external connection portion 5c, and an extension portion 5c2 that connects the terminal portion 5c1 and the substrate portion 5a. The terminal portion 5c1 is not closely opposed to the terminal portion 4c1 of the positive electrode plate 4, but is provided at a shifted position. On the other hand, the extending portion 5c2 is closely opposed to the extending portion 4c2 of the positive electrode plate 4. In other words, the portions of the external connection portion 5c that are close to each other and facing each other are the extension portions 5c2, and the portions that are not extended are the terminal portions 5c1.

As described above, the exterior case 6 is formed by connecting the partial component 31c of the assembly 3 and the case body 61. Although it is made of synthetic resin, the case body 61 may be made of metal as long as insulation can be ensured.

The filling resin 7 filled in the exterior case 6 is an insulating resin. Thermosetting resins and photocurable resins are preferred, such as epoxy resins, urethane resins, and silicone resins. The filling resin 7 is filled into the outer case 6 to such an extent that the covering part (or the substrate parts 4a and 5a if the covering part 31b is not provided) located in the partial component part 31c is buried.

In FIG. 1, reference numeral 9 is a grounding electrode plate connected to the Y capacitor.

Next, a method for manufacturing capacitor 1 will be explained. First, to explain the manufacturing method of the assembly 3, the positive electrode plate 4 and the negative electrode plate 5 are placed close to each other (a predetermined interval (for example, 1 mm) is left between the positive and negative electrode plates 4 and 5), and then the mold is molded. The assembly 3 is manufactured by setting the assembly 3 and casting it in resin. Next, the capacitor element 2 is connected to the element connection parts 4b and 5b of the positive and negative electrode plates 4 and 5. Specifically, the lead wires 23 extending from the electrode parts 2a, 2b of the capacitor element 2 are inserted into the insertion holes 4b1, 5b1 of the element connection parts 4b, 5b, and then connected by solder or the like. Incidentally, at this time, the grounding electrode plate 8 is also connected if necessary. Then, the assembly 3 and the case body 61 are connected so that the capacitor element 2 is housed in the case body 61. Specifically, the connecting portion 31c1 of the partial component portion 31c and the connected portion 61a of the case body 61 are connected to form the exterior case 6. As a result, the capacitor element 2 and mainly the substrate parts 4a and 5a of the positive and negative electrode plates 4 and 5 are housed in the housing part 6d of the exterior case 6. Finally, the filling resin 7 is filled into the outer case 6 through the hole 32 and cured to integrate the partial component 31c and the case body 61, completing the manufacturing of the capacitor 1 (see FIG. 3).

In the capacitor 1 having the above configuration, the positive electrode plate 4 and the negative electrode plate 5 are integrally molded with resin in advance, and the distance between the positive electrode plate 4 and the negative electrode plate 5 is fixed. There is no need to use a separate positioning jig to attach the case to the case, and the assembly work is simple. Furthermore, since the assembly 3 includes the partial component part 31c that constitutes a part of the exterior case 6, by attaching the assembly 3 to the case body 61 that constitutes the other part of the exterior case 6, positive and negative electrodes can be connected to the case. The plates 4 and 5 can also be positioned, and a positioning jig for this purpose is not required, simplifying the assembly work. Furthermore, since the outer peripheries of the extended parts 4c2 and 5c2 of the external connection parts 4c and 5c pulled out of the exterior case 6 are covered in advance with the covering part 31b, conductive parts are not brought close to the extended parts 4c2 and 5c2. This allows the capacitor 1 to be placed in a smaller size as a whole. In addition, since the interposed part 31a is interposed between the extending parts 4c2 and 5c2 which are close to each other in positive and negative directions, there is no need to separately insert an insulating member such as insulating paper between the extending parts 4c2 and 5c2. , easy to manufacture.

Although the embodiments of this invention have been described above, this invention is not limited to the above embodiments, and can be implemented with various changes within the scope of this invention. For example, the outer case 6 may include a lid. Furthermore, the partial component portion 31c may constitute part or all of the lid. In FIG. 1, the partial component 31c has a rectangular cylindrical shape, but it does not need to be continuous in the circumferential direction, and may have a partially chipped state or three or less sides, and one side wall portion It may constitute only a part of. Further, it may constitute part or all of the bottom portion 6a.

Various connection methods can be used to connect the partial component part 31c and the case body 61, such as fitting in a concave and convex part, or hooking with a claw. The mounting legs 33 may be provided on the case body 61 side. In the assembly 3, the positive and negative electrode plates 4 and 5 were integrally molded with resin, but another electrode plate for connecting the capacitor element 2, other electrical parts, etc., and external equipment is also integrally molded. You can. Further, it is not necessarily necessary to cover the entire extended portions 4c2 and 5c2 with the covering portion 31b; for example, if there is a portion that does not require insulation or a portion that cannot be covered due to connection with external equipment, it is not necessary to cover it. The number of assemblies 3 is not limited to one, and a plurality of assemblies 3 may be provided. For example, one capacitor may be manufactured by combining two or more assemblies 3 and the case body 61 and integrating them with the filling resin 7. In addition to integral molding by casting, the assembly 3 may be integrally molded by insert molding or heat shrink molding.

1 Capacitor 2 Capacitor element 21 DC capacitor 22 Y capacitor 2a One electrode portion 2b Other electrode portion 2c Flat portion 2d Curved portion 23 Lead wire 3 Assembly 31 Resin portion 31a Intervening portion 31b Covering portion 31c Partial component portion 31c1 Connection portion 32 Hole 33 Mounting leg 4 Positive electrode plate 4a Substrate part 4b Element connection part 4b1 Insertion hole 4c External connection part 4c1 Terminal part 4c2 Extension part 5 Negative electrode plate 5a Substrate part 5b Element connection part 5b1 Insertion hole 5c External connection part 5c1 Terminal part 5c2 Extension Part 6 Exterior case 6a Bottom part 6b Side wall part 6c Opening part 6d Housing part 61 Case body 61a Connected part 7 Filled resin 8 Grounding electrode plate

Claims (2)

a capacitor element,
An assembly in which a positive electrode plate and a negative electrode plate connected to a capacitor element are integrally molded with resin;
a case body that forms an exterior case by being connected with the assembly;
Comprising a filled resin that fills the outer case,
The positive electrode plate and the negative electrode plate are provided with an extension part that is pulled out of the outer case,
The extending portion of the positive electrode plate and the extending portion of the negative electrode plate are close to each other and face each other,
The resin part of the assembly includes a covering part that covers the outer periphery of the extending parts that are close to each other, an intervening part that is interposed between the extending parts, and a partial component part that is connected to the case body and forms a part of the outer case. Yes, there is a capacitor. A method for manufacturing a capacitor according to claim 1, comprising:
The positive electrode plate and the negative electrode plate are placed in a mold in close opposition to each other, and the assembly is manufactured by resin casting.
The assembly and the case body are connected to form an exterior case,
Fill the outer case with resin and harden it.
Production method.

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