Electrolytic capacitor

Abstract

To materialize an electrolytic capacitor that can be manufactured at low cost and has a high capacity.SOLUTION: The electrolytic capacitor comprises: a capacitor element provided with an anode part and a cathode part; an anode lead frame electrically connecting to the anode part; a cathode lead frame electrically connecting to the cathode part; and an outer package covering the capacitor element. The anode part includes an anode body and an anode wire extending from the planting surface of the anode body. The anode lead frame includes a first section exposed from a first main surface facing the planting surface of the outer package and extending along the first main surface, a second section bent from the first section and buried in the inside of the outer package, and a third section bent from the first section and extending along a second main surface interesting the first main surface. The second section has at least one connection part extending toward the planting surface. In a height direction relative to the second main surface of the outer package, the height at which the connection part extends is lower than or equal to a position at which the first section is exposed from the first surface.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electrolytic capacitor, and more particularly to a method for electrically connecting an anode part and an anode lead frame in an electrolytic capacitor. [Background technology]

[0002] Electrolytic capacitors are used in a variety of electronic devices due to their low equivalent series resistance (ESR) and excellent frequency characteristics. An electrolytic capacitor typically comprises a capacitor element with an anode and a cathode, an anode lead frame electrically connected to the anode, and a cathode lead frame electrically connected to the cathode. The capacitor element is typically sealed in an exterior case.

[0003] As a method of connecting an anode portion and an anode lead frame, Patent Document 1 discloses an electrolytic capacitor configured such that an internal bend is formed in an anode lead terminal (corresponding to an anode lead frame) having a first main surface and a second main surface, and a part of the anode lead terminal is bent inside an outer casing and joined to an anode wire. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2018 / 159426 Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, the internal bending portion includes a first internal bending portion that bends the anode lead terminal extending from the joint with the anode wire toward the first main surface, which is the joint surface with the anode wire, at a position where the anode lead terminal does not contact the anode wire, and a second internal bending portion that bends the anode lead terminal bent at the first internal bending portion in a direction along the anode wire and leads it out of the exterior housing. The anode lead terminal that has been led out of the exterior housing is further bent toward the first main surface and folded along the outer shape of the exterior housing, and is placed on the mounting surface of the exterior housing.

[0006] On the other hand, the cathode lead terminal contacts the capacitor element on the side opposite the mounting surface of the outer casing, and like the anode lead terminal, is bent toward the first main surface inside the outer casing and then bent toward the mounting surface, and then the bent cathode lead terminal is bent in a direction along the anode wire and led out of the outer casing.

[0007] When manufacturing this electrolytic capacitor, the capacitor element is positioned so that it fits into a step formed by the bent portion of the anode lead terminal and a step formed by the bent portion of the cathode lead terminal, the anode wire of the capacitor element is placed on the anode lead terminal, and the cathode portion of the capacitor element is placed on the cathode lead terminal.

[0008] In recent years, there has been an increasing demand for small, high-capacity electrolytic capacitors. However, when attempting to realize a small, high-capacity electrolytic capacitor using the above-mentioned method, the capacitor element is miniaturized and the space between the capacitor element and each bent portion of the anode and cathode lead terminals is reduced, requiring high positioning accuracy in mounting the capacitor element on the lead terminals.

[0009] Furthermore, in Patent Document 1, a capacitor is constructed by placing one capacitor element on a lead frame.

[0010] On the other hand, attempts have been made to reduce ESR and / or increase capacitance by arranging multiple capacitor elements on a lead frame or by changing the size of the capacitor elements arranged on the lead frame. However, when arranging multiple capacitor elements on a lead frame or changing the size of the capacitor elements arranged on the lead frame, it is necessary to change the configuration of the lead frame each time depending on the configuration of the capacitor elements. [Means for solving the problem]

[0011] In view of the above-described problems, one aspect of the present disclosure relates to an electrolytic capacitor including: at least one capacitor element including an anode portion and a cathode portion; an anode lead frame electrically connected to the anode portion; a cathode lead frame electrically connected to the cathode portion; and an exterior housing covering the capacitor element with the anode lead frame and a portion of the cathode lead frame exposed, wherein the anode portion has an anode body and an anode wire extending from an implantation surface of the anode body, and the anode lead frame has: a first portion exposed from a first main surface facing the implantation surface of the exterior housing and extending along the first main surface; and a second portion bent from the first portion and embedded in the exterior housing, the second portion having a plurality of connection portions extending toward the implantation surface, the plurality of connection portions including first connection portions and second connection portions, and the extension height of the first connection portions differs from the extension height of the second connection portions.

[0012] Another aspect of the present disclosure provides a capacitor comprising: at least one capacitor element including an anode portion and a cathode portion; an anode lead frame electrically connected to the anode portion; a cathode lead frame electrically connected to the cathode portion; and an exterior housing covering the capacitor element with the anode lead frame and a portion of the cathode lead frame exposed, wherein the anode portion has an anode body and an anode wire extending from an implantation surface of the anode body, and the anode lead frame has a first portion exposed from a first surface opposing the implantation surface of the exterior housing and extending along the first surface, and and a second portion bent from the first portion and embedded within the outer casing, the second portion having three or more connection portions extending toward the implantation surface, the three or more connection portions including a first connection portion and a second connection portion, at least one of the three or more connection portions being the first connection portion and at least two of the remaining connection portions being second connection portions, one of the first connection portion and the second connection portion being joined to the anode wire of the capacitor element, and the other of the first connection portion and the second connection portion not being joined to the anode wire of the capacitor element. [Effects of the Invention]

[0013] According to the present disclosure, it is possible to reduce manufacturing costs and realize a high-capacity electrolytic capacitor. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view schematically illustrating an electrolytic capacitor according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a side view of the electrolytic capacitor of FIG. [Figure 3] FIG. 2 is a top view of the electrolytic capacitor of FIG. [Figure 4] FIG. 1 is a schematic cross-sectional view of a capacitor element according to an embodiment of the present disclosure. [Figure 5] FIG. 3 is an enlarged schematic diagram showing the state of the anode lead frame inside the outer casing in FIG. [Figure 6] FIG. 1 is a perspective view schematically illustrating an electrolytic capacitor according to an embodiment of the present disclosure. [Figure 7] FIG. 7 is a side view of the electrolytic capacitor of FIG. 6. [Figure 8] FIG. 7 is a top view of the electrolytic capacitor of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] Examples of embodiments according to the present disclosure will be described below. While examples of embodiments according to the present disclosure will be described below, the present disclosure is not limited to the examples described below. While specific numerical values ​​and materials may be exemplified in the following description, other numerical values ​​and other materials may be applied as long as the effects of the present disclosure are obtained. In this specification, when a "range between numerical values ​​A and B" is used, the range includes numerical values ​​A and B, and can be interpreted as "greater than or equal to numerical value A and less than or equal to numerical value B." In the following description, when lower and upper limits for specific physical properties or conditions are exemplified, any of the exemplified lower limits and any of the exemplified upper limits can be arbitrarily combined, as long as the lower limit is not greater than or equal to the upper limit. When multiple materials are exemplified, one of the materials may be selected and used alone, or two or more of the materials may be used in combination.

[0016] The present disclosure also encompasses combinations of two or more features arbitrarily selected from the appended claims, i.e., two or more features arbitrarily selected from the appended claims can be combined unless a technical contradiction arises.

[0017] The electrolytic capacitor according to this embodiment includes at least one capacitor element having an anode portion and a cathode portion, an anode lead frame electrically connected to the anode portion, a cathode lead frame electrically connected to the cathode portion, and an exterior housing. The exterior housing covers the capacitor element while leaving portions of the anode lead frame and the cathode lead frame exposed. The anode portion includes an anode body and an anode wire extending from the implantation surface of the anode body.

[0018] The outer surface of the exterior housing has a first main surface. The first main surface is a surface facing the implanted surface of the anode body, and the anode wire extends from the implanted surface toward the first main surface. The outer surface of the exterior housing may also have a second main surface and a third main surface that share a side with the first surface. The second main surface and the third main surface face each other. The second main surface may be a surface that corresponds to the bottom surface of the electrolytic capacitor. The third main surface may be a surface that corresponds to the top surface of the electrolytic capacitor.

[0019] Electrolytic capacitors typically have a rectangular parallelepiped shape. In this case, the general shape of the exterior body is also a rectangular parallelepiped, and the first to third principal surfaces are the three faces of the rectangular parallelepiped. That is, the first to third principal surfaces of the exterior body are typically two mutually opposing faces and one face connecting the two opposing faces among the six faces of the exterior surface of the exterior body formed to form a roughly rectangular parallelepiped. However, these faces do not necessarily have to be flat; they may have a curved shape, have slight irregularities, and / or be formed by multiple bent planes. The angle between the first principal surface and the second principal surface, and the angle between the second principal surface and the third principal surface, may each be a right angle, an acute angle, or an obtuse angle. That is, one principal surface may be inclined with respect to the other principal surface.

[0020] The anode lead frame has a first portion and a second portion bent from the first portion. The first portion is exposed from a first main surface of the exterior package and extends from the exposed position along the first main surface. The second portion is embedded in the exterior package in a state where it is bent from the first portion. The second portion typically extends in a direction intersecting the first main surface of the exterior package, substantially parallel to the second main surface, toward the implantation surface of the anode wire.

[0021] The anode lead frame may have a third portion bent from the first portion and extending along a second surface that intersects with the first surface of the outer casing, the third portion being used for connection to an external circuit.

[0022] Note that the phrase "extending along the first main surface" does not necessarily mean that the part extends parallel to the first main surface, but may also mean that the part extends at a slight angle to the first main surface. It also does not necessarily mean that the part extends exposed from the first main surface, but may also mean that the part extends near the first main surface inside the exterior package. The same is true for the phrase "extending along the second or third main surface" of the lead frame.

[0023] The second portion has at least one connection portion extending toward the implantation surface, the connection portion being adapted for connection to an anode wire.

[0024] The height to which at least one connection portion extends is equal to or less than the height of the position where the first portion is exposed from the first surface. Here, the height of the connection portion is determined based on the second main surface of the exterior body (the surface corresponding to the bottom surface of the electrolytic capacitor). The direction perpendicular to the second main surface is defined as the height direction. In this case, the second portion is not bent, or it can be bent toward the second main surface and then joined to the anode body at the connection portion. In this case, even if the position of the capacitor element is shifted in the extension direction of the anode wire when mounting the capacitor element on the lead frame, the bent portion of the anode lead frame does not become an obstacle, and the joining point of the anode wire with the connection portion changes, allowing the electrolytic capacitor to be manufactured. This increases the positioning margin when mounting the capacitor element on the lead frame, reducing manufacturing defects.

[0025] If the height to which the connection portion extends is set to be equal to or less than the height of the position where the first portion is exposed from the first surface, the reduced height of the connection portion increases the distance between the capacitor element and the third main surface, which may hinder an increase in capacitance. By increasing the height to which the first portion is exposed from the first surface, the height to which the connection portion extends can be set to a desired height, resulting in a high-capacity electrolytic capacitor. The height to which the first portion is exposed from the first surface may be higher than the height of the center position in the height direction of the exterior body.

[0026] Here, the distance between the second main surface and the third main surface is defined as the height H of the exterior body, and the distance from the second main surface to the position where the first portion is exposed from the first main surface is defined as height H1. Height H1 is approximately equal to the length of the first portion extending along the first main surface. When height H1 is smaller than H / 2, the position where the first portion is exposed from the first main surface is on the second main surface side with respect to the center position. When height H1 is greater than H / 2, the position where the first portion is exposed from the first main surface is on the opposite side of the second main surface with respect to the center position. The position where the first portion is exposed from the first main surface may also be on the opposite side of the second main surface with respect to the center position.

[0027] In one embodiment of the connection portion in which the extension height is lower than the height of the position where the first portion is exposed from the first surface, the second portion of the anode lead frame may have a fourth portion that bends from the first portion and extends within the package toward the implantation surface, a fifth portion that bends from the fourth portion and extends within the package toward the first portion (or the third portion), and a sixth portion that bends from the fifth portion and extends within the package toward the implantation surface again. In other words, the second portion may be bent toward the second main surface so as to form a crank within the package. The height to which the sixth portion extends is adjusted by the bending. The sixth portion constitutes the connection portion. Here, the phrase "the fifth portion bends and extends in a direction approaching the first portion (or the third portion)" means that the fifth portion extends so that the distance to the first portion or the third portion is shorter than when the fifth portion extends without bending. This phrase defines the direction of bending, but does not limit the angle of bending. The bending angle is not necessarily limited to 90° (a right angle) and can be any angle greater than 0° and less than 180°. The phrase "the fifth portion bends and extends in a direction approaching the first portion (or the third portion)" also means that the fifth portion extends in a direction toward the second main surface and away from the third main surface. The phrase "the fifth portion bends and extends in a direction away from the first portion (or the third portion)" means that the fifth portion extends in a direction away from the second main surface and toward the third main surface.

[0028] In one embodiment, the second portion may have a plurality of connection portions extending toward the implantation surface. The plurality of connection portions include a first connection portion and a second connection portion. The first connection portion and the second connection portion are each provided for connection to an anode wire. Depending on the configuration of the capacitor element, either the first connection portion or the second connection portion can be selected and used for connection to the anode wire.

[0029] The height to which the first connection portion extends may be different from the height to which the second connection portion extends. In other words, the anode lead frame has a plurality of connection portions for connecting to anode wires at different heights. In this case, either the first connection portion or the second connection portion can be selected and used for joining to the anode wire depending on the contact height when the anode wire of the capacitor element comes into contact with the connection portion. For example, by varying the configuration of the anode wire, it becomes possible to share the anode lead frame when manufacturing multiple types of electrolytic capacitors with different capacitor element characteristics.

[0030] In one embodiment, the second portion has three or more connection portions, including at least one first connection portion and at least two second connection portions. One of the first connection portion and the second connection portion is bonded to an anode wire of the capacitor element. Meanwhile, the other of the first connection portion and the second connection portion is not bonded to the anode wire of the capacitor element. Depending on the configuration of the capacitor element, either the first connection portion or the second connection portion is selected and used for bonding to the anode wire. In this case, there is a dummy connection portion that is not used for bonding to the anode wire.

[0031] In this embodiment, the height to which the first connecting portion and / or the second connecting portion extends may be lower or higher than the height at the position where the first portion is exposed from the first main surface.

[0032] One of the first connection portion and the second connection portion may be connected to an anode wire of the capacitor element, while the other of the first connection portion and the second connection portion is not connected to the anode wire of the capacitor element and constitutes a dummy connection portion.

[0033] The connector may have three or more connection portions. In this case, at least one of the three or more connection portions may be a first connection portion and at least two of the remaining connection portions may be second connection portions. In this case, one first connection portion may be disposed between two second connection portions.

[0034] In one example of a case where there are three or more connection portions, a first connection portion may be connected to an anode wire of one capacitor element, and a second connection portion may be a dummy connection portion that is not connected to an anode wire of a capacitor element.

[0035] As another example of a case where there are three or more connection parts, a plurality of the capacitor elements may be provided, the number of which is equal to the number of second connection parts, and each of the second connection parts may be connected to the anode wire of the corresponding capacitor element. The first connection parts are not connected to the anode wire, and constitute dummy connection parts.

[0036] The first and second connection parts, which extend to different heights, can be formed by bending at least one of the first and second connection parts within the exterior housing. The first connection part may be bent within the exterior housing before extending toward the implantation surface, and the second connection part may extend without bending within the exterior housing. Conversely, the second connection part may be bent within the exterior housing before extending toward the implantation surface, and the first connection part may extend without bending within the exterior housing.

[0037] As described above, one of the first connection portion and the second connection portion is used for joining to the anode wire, while the other of the first connection portion and the second connection portion is a dummy connection portion that is not used for joining to the anode wire. The connection portion used for joining to the anode wire may be bent within the exterior housing when joined to the anode wire, or may be joined to the anode wire without being bent within the exterior housing. The dummy connection portion may extend within the exterior housing in a bent state, or may extend within the exterior housing without being bent.

[0038] An electrolytic capacitor according to one embodiment includes at least one capacitor element having an anode portion and a cathode portion, an anode lead frame electrically connected to the anode portion, a cathode lead frame electrically connected to the cathode portion, and an exterior housing that covers the capacitor element with the anode lead frame and a portion of the cathode lead frame exposed. The anode portion includes an anode body and an anode wire extending from an implantation surface of the anode body. The anode lead frame includes a first portion that is exposed from a first surface facing the implantation surface of the exterior housing and extends along the first surface, and a second portion that is bent from the first portion and embedded in the exterior housing. The second portion has three or more connection portions that extend toward the implantation surface. The three or more connection portions may include a first connection portion and a second connection portion. At least one of the three or more connection portions may be a first connection portion and at least two of the remaining connection portions may be second connection portions. One of the first and second connection parts is connected to the anode wire of the capacitor element, and the other of the first and second connection parts is not connected to the anode wire of the capacitor element, which makes it possible to share the anode lead frame when manufacturing multiple types of electrolytic capacitors with different capacitor element characteristics.

[0039] As an example of an embodiment in which the first connection portion and / or the second connection portion is bent within the outer casing, the second portion of the anode lead frame may have a fourth portion bent from the first portion and extending within the outer casing toward the implantation surface, a fifth portion bent from the fourth portion and extending within the outer casing in a direction intersecting the second main surface, and a sixth portion bent from the fifth portion and extending within the outer casing again toward the implantation surface. In other words, the second portion may be bent to form a crank within the outer casing. The bending adjusts the extension height of the sixth portion. The sixth portion constitutes the first connection portion or the second connection portion. The fifth portion may be bent from the fourth portion and extend toward the first portion (or toward the third portion) (so that the height of the connection portion decreases), or may be bent from the fourth portion and extend away from the first portion (so that the height of the connection portion increases).

[0040] Hereinafter, an electrolytic capacitor according to an embodiment of the present invention will be described with reference to the drawings. In this embodiment, an anode lead frame having three connection portions with the anode wire is illustrated, but the present invention is not limited to this.

[0041] First Embodiment Fig. 1 is a perspective view schematically illustrating an electrolytic capacitor 100 according to one embodiment of the present invention. Fig. 2 is a side view of the electrolytic capacitor 100 in Fig. 1, and Fig. 3 is a top view. Fig. 4 is a schematic cross-sectional view of a capacitor element 10 used in the electrolytic capacitor 100.

[0042] Electrolytic capacitor 100 includes a capacitor element 10 having an anode portion 6 and a cathode portion 7, an anode lead frame 20 electrically connected to the anode portion 6, a cathode lead frame 25 electrically connected to the cathode portion 7, and an exterior housing 30. Exterior housing 30 covers capacitor element 10, leaving portions of anode lead frame 20 and cathode lead frame 25 exposed. Anode portion 6 has an anode body 1 and an anode wire 2 extending from anode body 1, and anode wire 2 is joined to anode lead frame 20.

[0043] The outer surface of the exterior housing 30 has a first main surface S1, a second main surface S2 and a third main surface S3 that share one side with the first main surface S1, and a fourth main surface S4 that shares one side with each of the second main surface S2 and the third main surface S3 (see FIG. 2). The first main surface S1 is a surface that faces an implantation surface 1P in the anode body 1 where the anode wire 2 is implanted. The anode wire 2 extends from the implantation surface toward the first main surface S1. The second main surface S2 and the third main surface S3 face each other. The second main surface S2 corresponds to the bottom surface of the electrolytic capacitor 100, and the third main surface S3 corresponds to the top surface of the electrolytic capacitor 100.

[0044] Capacitor element 10 includes an anode portion 6 and a cathode portion 7. Anode portion 6 includes an anode body 1 including a dielectric layer 3, and an anode wire 2. Cathode portion 7 includes a solid electrolyte layer 4 formed on dielectric layer 3, and a cathode layer 5 covering the surface of solid electrolyte layer 4. Anode wire 2 is embedded inside anode body 1 from one surface (implantation surface) of anode body 1, and a part of it extends beyond the above surface of anode body 1.

[0045] The anode lead frame 20 has a first portion 21, a second portion 22, and a third portion 23. The first portion 21 is exposed from the first main surface S1 of the package 30 and extends from the exposed position X along the first main surface S1. The second portion 22 is bent from the first portion 21 and is embedded in the package 30 in a state bent from the first portion. The second portion 22 extends substantially parallel to the second main surface in a direction intersecting the first main surface S1 of the package 30, and extends toward the implantation surface 1P.

[0046] Third portion 23 of anode lead frame 20 is bent from first portion 21 and extends along second main surface S2. Third portion 23 forms a connection terminal (anode terminal) for connecting to an external circuit.

[0047] Cathode lead frame 25 has first portion 26, second portion 27, and third portion 28. First portion 26 is exposed from fourth main surface S4 opposite first main surface S1 of package 30, and extends from the exposed position along fourth main surface S4. Second portion 27 is embedded in package 30 in a bent state from first portion 26.

[0048] Second portion 27 extends substantially parallel to third principal surface S3 while bending within package 30, and is electrically connected on the third principal surface S3 side to the cathode portion of capacitor element 10. Second portion 27 is electrically connected to the cathode portion via a conductive adhesive layer (e.g., silver paste) 29 on the surface of the cathode portion facing third principal surface S3.

[0049] The third portion 28 is bent from the first portion 26 and extends along the second main surface S2. The third portion 28 forms a connection terminal (cathode terminal) to an external circuit.

[0050] 1 to 3, height H1 of exposed position X is higher than the center position in the height direction of package 30. That is, as shown in Fig. 2, when the distance between second main surface S2 and third main surface S3 of package 30 is H, H1>H / 2 holds. Exposed position X is on the opposite side of second main surface S2 from the center position in the height direction of package 30 (i.e., on the side of third main surface S3).

[0051] 3 , within the exterior package 30, the second portion 22 is divided into three parts at the end facing the implantation surface 1P. Each of the three parts can be used as a connection portion for joining the anode lead frame 20 and the anode wire 2. At least one of the three parts can be selected and used to join the anode lead frame 20 and the anode wire 2.

[0052] 1 to 3, one of the three connection portions is a first connection portion 221, and two of the three connection portions are second connection portions 222. The first connection portion 221 is located between the second connection portions 222. The first connection portion 221 is joined to the anode wire 2. The second connection portion 222 is not joined to the anode wire 2 and is a dummy connection portion.

[0053] The first connecting portion 221 extends toward the implantation surface 1P without bending within the exterior package 30. As a result, the height to which the first connecting portion 221 extends (height based on the second main surface S2) is approximately the same as the height H1 of the exposed position X where the first portion 21 is exposed from the first main surface S1. On the other hand, the second connecting portion 222 bends within the exterior package and then extends toward the implantation surface 1P after bending. As a result, the height to which the second connecting portion 222 extends (height based on the third portion 23) is shorter than the height to which the first connecting portion 221 extends.

[0054] 5 is an enlarged schematic diagram of the anode lead frame 20 in region A surrounded by a dashed line in FIG. 2, illustrating the state of the second portion 22 of the anode lead frame 20 within the exterior packaging. In the example of FIG. 5, the second portion 22 includes a fourth portion 22A that bends from the first portion 21 and extends within the exterior packaging toward the implantation surface, a fifth portion 22B that bends from the fourth portion 22A and extends within the exterior packaging in a direction intersecting the second main surface S2, and a sixth portion 22C that bends from the fifth portion 22B and extends further within the exterior packaging toward the implantation surface. The sixth portion 22C constitutes the second connection portion 222. The fifth portion 22B bends and extends from the fourth portion 22A in a direction approaching the first portion 21 (a direction approaching the third portion 23), thereby forming the second connection portion 222 that is shorter in height than the first connection portion 221.

[0055] Electrolytic capacitor 100 is manufactured by placing capacitor element 10 on a lead frame so that cathode portion 7 of capacitor element 10 contacts second portion 27 of cathode lead frame 25 and anode wire 2 contacts second portion 22 of anode lead frame 20, then welding anode wire 2 to the connection portion of second portion 22, and then sealing capacitor element 10 with exterior housing 30. In the step of placing capacitor element 10 on the lead frame, the capacitor element may be placed at a position closer to the first main surface than portion 27X of second portion 27 of cathode lead frame 25 that bends and extends in a direction intersecting the second main surface within the exterior housing.

[0056] In the second portion 22 of the anode lead frame 20, the first connection portion 221 to be joined to the anode wire 2 extends without bending within the package 30, and therefore does not have a step protruding toward the third main surface. On the other hand, the second connection portion 222 extends in a bent manner from the fifth portion 22B extending toward the second main surface, but because it is not used for connecting to the capacitor element 10, it does not hinder the placement of the capacitor element 10 on the lead frame. The capacitor element 10 only needs to be placed on the anode lead frame 20 so that the anode wire 2 overlaps part of the first connection portion 221, which allows for some leeway in positioning the capacitor element when placing it on the lead frame. As a result, manufacturing defects in electrolytic capacitors can be reduced.

[0057] Second Embodiment FIG. 6 is a perspective view schematically illustrating an electrolytic capacitor 101 according to one embodiment of the present invention. FIG. 7 is a side view of the electrolytic capacitor 101 in FIG. 6, and FIG. 8 is a top view. The anode lead frame and cathode lead frame used in the electrolytic capacitor 101 are the same as the anode lead frame 20 and cathode lead frame 25 of the electrolytic capacitor 100 described above. The electrolytic capacitor 101 has the same external shape as the electrolytic capacitor 100. However, the configuration of the capacitor element mounted within the electrolytic capacitor is different.

[0058] Electrolytic capacitor 101 includes two capacitor elements 10A and 10B. Like capacitor element 10, capacitor elements 10A and 10B include an anode section 6 having an anode body 1 and an anode wire 2 extending from the anode body 1, and a cathode section 7, and have the same configuration as in Fig. 4, but differ in the size of the anode body 1 in anode section 6 and the diameter of the anode wire.

[0059] 6 to 8, of the three connection portions of anode lead frame 20, first connection portion 221 is a dummy connection portion that is not joined to anode wire 2 of either capacitor element 10A or 10B. On the other hand, one of two second connection portions 222 is joined to anode wire 2 of capacitor element 10A, and the other second connection portion 222 is joined to the anode wire of capacitor element 10B.

[0060] The diameter of the anode wire 2 in capacitor elements 10A and 10B is smaller than that in capacitor element 10. Therefore, the height of the anode wire 2 (height relative to the second main surface S2) when an electrolytic capacitor is constructed is also small. However, by forming the second connection portion 222 by bending the second portion within the exterior housing, it is possible to decrease (or increase) the height of the second connection portion 222. Therefore, the second connection portion 222 whose height has been decreased by bending can be used to join the anode wire of capacitor elements 10A and 10B.

[0061] Capacitor element 10 has a large element volume, making it easy to achieve high capacitance. On the other hand, electrolytic capacitor 101 made up of capacitor elements 10A and 10B has a lower ESR than electrolytic capacitor 100 made up of capacitor element 10 because the surface area covered by cathode layer 5 is larger, and because capacitor elements 10A and 10B are connected in parallel to the anode lead frame, the ESR is lower than that of electrolytic capacitor 100. By sharing anode lead frame 20, electrolytic capacitors with different characteristics such as ESR and capacitance can be produced separately.

[0062] In the above embodiment, a case has been described in which the first connecting portion 221 extends toward the implantation surface 1P without bending within the exterior body 30, and the second connecting portion 222 bends within the exterior body, then bends and extends toward the implantation surface. However, the present invention is not limited to this, and the second connecting portion 222 may extend toward the implantation surface 1P without bending within the exterior body 30, and the first connecting portion 221 may bend within the exterior body, then bend and extend toward the implantation surface.

[0063] In the above embodiment, an example has been described in which the fifth portion 22B of the second portion 22 is bent and extends from the fourth portion 22A in a direction approaching the first portion 21 to form the second connecting portion 222 that is shorter in height than the first connecting portion 221. However, the present invention is not limited to this, and the fifth portion 22B may be bent and extends from the fourth portion 22A in a direction away from the first portion 21 to form the second connecting portion 222 that is taller than the first connecting portion 221.

[0064] Each component of the electrolytic capacitor according to this embodiment will be described in detail below.

[0065] (anode part) The anode portion has an anode body and an anode wire extending from one surface of the anode body and electrically connecting to the anode lead frame. The anode body is, for example, a rectangular porous sintered body obtained by sintering metal particles. The metal particles used are particles of a valve metal such as titanium (Ti), tantalum (Ta), or niobium (Nb). The anode body 1 uses one or more types of metal particles. The metal particles may be an alloy made of two or more types of metals. For example, an alloy containing a valve metal and silicon, vanadium, boron, or the like may be used. Alternatively, a compound containing a valve metal and a typical element such as nitrogen may be used. The valve metal alloy preferably contains a valve metal as the main component, with the valve metal accounting for 50 atomic % or more.

[0066] The anode wire is made of a conductive material. The material of the anode wire is not particularly limited, and examples thereof include the valve metals mentioned above, as well as copper, aluminum, and aluminum alloys. The materials constituting the anode body and the anode wire may be the same or different. The cross-sectional shape of the anode wire is not particularly limited, and examples thereof include a circle, a track shape (a shape consisting of parallel straight lines and two curves connecting the ends of these lines), an ellipse, a rectangle, and a polygon. Of these, a track shape is preferred because it suppresses rolling during welding to the anode lead frame and makes positioning easier. The diameter of the anode wire (the major axis in the case of a track shape or an ellipse) is also not particularly limited, and is, for example, 0.1 mm or more and 1.0 mm or less.

[0067] A dielectric layer is formed on the surface of the anode body. The dielectric layer is made of, for example, a metal oxide. Methods for forming a layer containing a metal oxide on the surface of the anode body include, for example, a method of anodizing the surface of the anode body by immersing the anode body in a chemical conversion solution, and a method of heating the anode body in an oxygen-containing atmosphere. The dielectric layer is not limited to the layer containing the metal oxide, and may be any layer having insulating properties.

[0068] (cathode) The cathode section has a solid electrolyte layer formed on a dielectric layer and a cathode layer covering the solid electrolyte layer. The solid electrolyte layer may be formed so as to cover at least a portion of the dielectric layer. For example, a manganese compound or a conductive polymer may be used for the solid electrolyte layer. Examples of conductive polymers include polypyrrole, polythiophene, polyfuran, polyaniline, polyacetylene, polyphenylene, polyparaphenylene vinylene, polyacene, polythiophene vinylene, polyfluorene, polyvinyl carbazole, polyvinyl phenol, polypyridine, or derivatives of these polymers. These may be used alone or in combination. The conductive polymer may also be a copolymer of two or more monomers. Among these, polythiophene, polyaniline, polypyrrole, and the like are preferred due to their excellent conductivity. Among these, polypyrrole is preferred due to its excellent water repellency.

[0069] The solid electrolyte layer containing the conductive polymer is formed, for example, by polymerizing a raw material monomer on the dielectric layer 3. Alternatively, it is formed by applying a liquid containing the conductive polymer to the dielectric layer 3. The solid electrolyte layer is composed of one or more solid electrolyte layers. When the solid electrolyte layer is composed of two or more layers, the composition and forming method (polymerization method) of the conductive polymer used in each layer may be different.

[0070] The cathode layer has, for example, a carbon layer formed to cover the solid electrolyte layer and a metal paste layer formed on the surface of the carbon layer. The carbon layer contains a conductive carbon material such as graphite and a resin. The metal paste layer contains, for example, metal particles (e.g., silver) and a resin. The configuration of the cathode layer is not limited to this configuration. The configuration of the cathode layer may be any configuration that has a current collecting function.

[0071] (anode lead frame) The anode lead frame is electrically connected to the anode body via an anode wire. The material of the anode lead frame is not particularly limited as long as it is electrochemically and chemically stable and conductive, and may be metallic or non-metallic. The shape of the anode lead frame is, for example, a long, flat plate. From the viewpoint of reducing the height, the thickness of the anode lead frame (the distance between the main surfaces of the anode lead frame) is preferably 25 μm or more and 200 μm or less, and more preferably 25 μm or more and 100 μm or less.

[0072] The anode lead frame may be joined to the anode wire by a conductive adhesive, solder, resistance welding, laser welding, etc. The conductive adhesive may be, for example, a mixture of a thermosetting resin (described later) with carbon particles or metal particles.

[0073] (cathode lead frame) The cathode lead frame is electrically connected to the cathode part. The material of the cathode lead frame is not particularly limited, and may be either metallic or non-metallic, as long as it is electrochemically and chemically stable and conductive. The shape of the cathode lead frame is also not particularly limited, and may be, for example, a long, flat plate. From the viewpoint of reducing the height, the thickness of the cathode lead frame is preferably 25 to 200 μm, more preferably 25 to 100 μm. The cathode lead frame is bonded to the cathode part, for example, via a conductive adhesive.

[0074] (exterior body) The exterior body is provided to electrically insulate the anode lead frame and the cathode lead frame and is made of an insulating material. The exterior body includes, for example, a cured thermosetting resin. Examples of thermosetting resins include epoxy resin, phenol resin, silicone resin, melamine resin, urea resin, alkyd resin, polyurethane, polyimide, and unsaturated polyester.

[0075] (Addendum) The above description of the embodiments discloses the following techniques. (Technology 1) at least one capacitor element having an anode portion and a cathode portion; an anode lead frame electrically connected to the anode portion; a cathode lead frame electrically connected to the cathode portion; an exterior body that covers the capacitor element while leaving portions of the anode lead frame and the cathode lead frame exposed, The anode part is an anode body; an anode wire extending from the implantation surface of the anode body, The anode lead frame is a first portion exposed from a first main surface of the exterior body facing the planting surface and extending along the first main surface; a second portion bent from the first portion and embedded in the exterior body; a third portion that is bent from the opposite side of the boundary between the first portion and the second portion without being embedded in the exterior housing and extends along a second main surface that intersects with the first main surface of the exterior housing, The second portion has at least one connecting portion extending toward the planting surface, An electrolytic capacitor in which the height to which the at least one connection portion extends in a height direction based on the second main surface of the outer casing is equal to or less than the height based on the second main surface at a position where the first portion is exposed from the first surface. (Technology 2) The electrolytic capacitor according to technology 1, wherein the position at which the first portion of the exterior body is exposed from the first main surface is on the opposite side of the second main surface with respect to the center position of the exterior body in the height direction. (Technology 3) The second portion is a fourth portion that bends from the first portion and extends inside the exterior body toward the implantation surface; a fifth portion bent from the fourth portion and extending inside the exterior body in a direction toward the second main surface; a sixth portion that is bent from the fifth portion and extends again toward the implantation surface within the exterior body, The electrolytic capacitor according to Technology 1 or 2, wherein the sixth portion constitutes the at least one connection portion. (Technology 4) a plurality of said connection portions; the plurality of connection portions include a first connection portion and a second connection portion, 4. The electrolytic capacitor according to any one of techniques 1 to 3, wherein the height to which the first connecting portion extends is different from the height to which the second connecting portion extends. (Technology 5) one of the first connection portion and the second connection portion is joined to the anode wire of the capacitor element; The electrolytic capacitor according to claim 4, wherein the other of the first connection portion and the second connection portion is not joined to the anode wire of the capacitor element. (Technology 6) having three or more of the connection portions, 6. The electrolytic capacitor according to claim 4, wherein at least one of the three or more connection portions is the first connection portion and at least two of the three or more connection portions are the second connection portions. (Technology 7) at least one capacitor element having an anode portion and a cathode portion; an anode lead frame electrically connected to the anode portion; a cathode lead frame electrically connected to the cathode portion; an exterior body that covers the capacitor element while leaving portions of the anode lead frame and the cathode lead frame exposed, The anode part is an anode body; an anode wire extending from the implantation surface of the anode body, The anode lead frame is a first portion exposed from a first surface of the exterior body facing the planting surface and extending along the first surface; a second portion bent from the first portion and embedded in the exterior body, The second portion has three or more connecting portions extending toward the planting surface, the three or more connection portions include a first connection portion and a second connection portion, At least one of the three or more connection portions is the first connection portion and at least two of the three or more connection portions are the second connection portions; one of the first connection portion and the second connection portion is joined to the anode wire of the capacitor element; an electrolytic capacitor, wherein the other of the first connection portion and the second connection portion is not joined to the anode wire of the capacitor element; (Technology 8) 8. The electrolytic capacitor according to claim 6, wherein one of the first connection portions is located between two of the second connection portions. (Technology 9) the first connection portion is joined to the anode wire of one of the capacitor elements; The electrolytic capacitor according to claim 8, wherein the second connection portion is not joined to the anode wire. (Technology 10) a plurality of the capacitor elements, the number of which is equal to the number of the second connection parts; each of the second connection portions is joined to the anode wire of the corresponding capacitor element; The electrolytic capacitor according to claim 8, wherein the first connection portion is not joined to the anode wire. (Technology 11) the first connection portion is bent within the exterior body and then extends toward the implantation surface, 11. The electrolytic capacitor according to any one of techniques 4 to 10, wherein the second connection portion extends toward the implantation surface without being bent within the exterior package. (Technology 12) the second connection portion is bent within the exterior body and then extends toward the implantation surface, 11. The electrolytic capacitor according to any one of techniques 4 to 10, wherein the first connection portion extends toward the implantation surface without being bent within the exterior package. (Technology 13) the second portion has a fourth portion that bends from the first portion and extends within the exterior body toward the planting surface, a fifth portion that bends from the fourth portion and extends within the exterior body in a direction approaching the first portion, and a sixth portion that bends from the fifth portion and extends within the exterior body again toward the planting surface, The electrolytic capacitor according to technology 11, wherein the sixth portion constitutes the first connecting portion. (Technology 14) the second portion has a fourth portion that bends from the first portion and extends within the exterior body toward the planting surface, a fifth portion that bends from the fourth portion and extends within the exterior body in a direction approaching the first portion, and a sixth portion that bends from the fifth portion and extends within the exterior body again toward the planting surface, The electrolytic capacitor according to technology 12, wherein the sixth portion constitutes the second connection portion. [Industrial Applicability]

[0076] The electrolytic capacitor according to the present invention can be used for a variety of purposes because it allows a common anode lead frame to be used when manufacturing a plurality of types of electrolytic capacitors with different characteristics. [Explanation of symbols]

[0077] 100, 101: Electrolytic capacitor 10, 10A, 10B: Capacitor elements 1: Anode body 2: Anode wire 3: Dielectric layer 4: Solid electrolyte layer 5: Cathode layer 6: Anode part 7: Cathode 20: Anode lead frame 21: Part 1 22:Second part 221: First connection part 222: Second connection part 22A: 4th part 22B: 5th part 22C: Part 6 23: Third part 25: Cathode lead frame 26: Part 1 27:Second part 28: Third part 29: Conductive adhesive layer 30: Exterior body S1: First main surface S2: 2nd principal surface S3: Third principal surface S4: Fourth principal surface

Claims

1. at least one capacitor element having an anode portion and a cathode portion; an anode lead frame electrically connected to the anode portion; a cathode lead frame electrically connected to the cathode portion; an exterior body that covers the capacitor element while leaving portions of the anode lead frame and the cathode lead frame exposed, The anode part is an anode body; an anode wire extending from the implantation surface of the anode body, The anode lead frame is a first portion exposed from a first main surface of the exterior body facing the planting surface and extending along the first main surface; a second portion bent from the first portion and embedded in the exterior body; a third portion that is bent from the opposite side of the boundary between the first portion and the second portion without being embedded in the exterior body and extends along a second main surface that intersects with the first main surface of the exterior body, The second portion has at least one connecting portion extending toward the planting surface, An electrolytic capacitor, wherein the height to which the at least one connection portion extends in a height direction based on the second main surface of the outer casing is equal to or less than the height based on the second main surface at a position where the first portion is exposed from the first surface.

2. 2. The electrolytic capacitor according to claim 1, wherein the position at which the first portion of the exterior body is exposed from the first main surface is on the opposite side of the second main surface with respect to a center position of the exterior body in the height direction.

3. The second portion is a fourth portion bent from the first portion and extending inside the exterior body toward the planting surface; a fifth portion bent from the fourth portion and extending inside the exterior body in a direction toward the second main surface; a sixth portion that is bent from the fifth portion and extends again toward the planting surface within the exterior body, The electrolytic capacitor of claim 1 , wherein the sixth portion constitutes the at least one connection portion.

4. a plurality of said connection portions; the plurality of connection portions include a first connection portion and a second connection portion, The electrolytic capacitor according to claim 1 , wherein the height to which the first connection portion extends is different from the height to which the second connection portion extends.

5. one of the first connection portion and the second connection portion is joined to the anode wire of the capacitor element; The electrolytic capacitor according to claim 4 , wherein the other of the first connection portion and the second connection portion is not joined to the anode wire of the capacitor element.

6. having three or more of the connection portions, 5. The electrolytic capacitor according to claim 4, wherein at least one of the three or more connection portions is the first connection portion and at least two of the three or more connection portions are the second connection portions.

7. at least one capacitor element having an anode portion and a cathode portion; an anode lead frame electrically connected to the anode portion; a cathode lead frame electrically connected to the cathode portion; an exterior body that covers the capacitor element while leaving portions of the anode lead frame and the cathode lead frame exposed, The anode part is an anode body; an anode wire extending from the implantation surface of the anode body, The anode lead frame is a first portion exposed from a first surface of the exterior body facing the planting surface and extending along the first surface; a second portion bent from the first portion and embedded in the exterior body, The second portion has three or more connecting portions extending toward the planting surface, the three or more connection portions include a first connection portion and a second connection portion, At least one of the three or more connection portions is the first connection portion and at least two of the three or more connection portions are the second connection portions, one of the first connection portion and the second connection portion is joined to the anode wire of the capacitor element; an electrolytic capacitor, wherein the other of the first connection portion and the second connection portion is not joined to the anode wire of the capacitor element;

8. 8. The electrolytic capacitor according to claim 6, wherein one of the first connection portions is located between two of the second connection portions.

9. the first connection portion is joined to the anode wire of one of the capacitor elements; The electrolytic capacitor of claim 8 , wherein the second connection portion is not joined to the anode wire.

10. a plurality of the capacitor elements, the number of which is equal to the number of the second connection portions; each of the second connection portions is joined to the anode wire of the corresponding capacitor element; The electrolytic capacitor of claim 8 , wherein the first connection portion is not joined to the anode wire.

11. the first connection portion is bent within the exterior body and then extends toward the implantation surface, 8. The electrolytic capacitor according to claim 4, wherein the second connection portion extends toward the implantation surface without being bent within the exterior body.

12. the second connection portion is bent within the exterior body and then extends toward the implantation surface, 8. The electrolytic capacitor according to claim 4, wherein the first connection portion extends toward the implantation surface without being bent within the exterior body.

13. The second portion is a fourth portion bent from the first portion and extending inside the exterior body toward the planting surface; a fifth portion bent from the fourth portion and extending within the exterior body in a direction approaching the first portion; a sixth portion that is bent from the fifth portion and extends again toward the planting surface within the exterior body, The electrolytic capacitor according to claim 11 , wherein the sixth portion constitutes the first connection portion.

14. The second portion is a fourth portion bent from the first portion and extending inside the exterior body toward the planting surface; a fifth portion bent from the fourth portion and extending within the exterior body in a direction approaching the first portion; a sixth portion that is bent from the fifth portion and extends again toward the planting surface within the exterior body, The electrolytic capacitor according to claim 12 , wherein the sixth portion constitutes the second connection portion.

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