Capacitor

Abstract

To provide a capacitor which can prevent removal between a bus bar and filling resin, and cracking of the filling resin even when the temperature changes.SOLUTION: A capacitor comprises: a capacitor element 10 having an element body 11 and an external electrode provided on a surface of the element body 11; a bus bar (a first bus bar 20a) which is electrically connected to the external electrode; an outer case 30 which has a bottomed cylindrical shape provided with an opening 31, and which internally houses the capacitor element 10 such that the bus bar (the first bus bar 20a) protrudes from the opening 31 to the outside; and filling resin 40 which is filled inside the outer case 30 so as to embed the capacitor element 10. A portion, of the bus bar, located between the capacitor element 10 and the opening 31 is provided with a first through-hole 21aa. A penetration direction DHaa in which the first through-hole 21aa extends forms an angle of less than 45° with respect to an opening surface 31s of the opening 31. The entire part of the first through-hole 21aa is embedded in the filling resin 40.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a capacitor.

Background Art

[0002] Patent Document 1 discloses a capacitor in which a capacitor element (1) is housed in a case (2) and filled with resin (3), and external connection terminals (6) and (7) are led out from the filled resin (3). In the external connection terminals (6) and (7), a constricted portion (10) having a smaller cross-sectional area than other portions is provided at a position in contact with the resin surface and in the vicinity thereof.

[0003] Patent Document 2 discloses an electrical component in which an electrical element (21) having a connection terminal (11) for connection to the outside of a case (31) is housed in the case (31) such that the tip of the connection terminal (11) protrudes outside the case (31), and the case (31) is filled with resin (32). A through hole (13) and a protruding portion (14) extending from the inside to the outside of the case are provided near the boundary portion from the inside to the outside of the case (31) of the connection terminal (11), and the resin (32) is filled such that a part of each of the through hole (13) and the protruding portion (14) is covered with the resin (32).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] As disclosed in Patent Document 1 and Patent Document 2, as a conventional capacitor, a capacitor element to which a bus bar (lead-out terminal) is electrically connected is housed inside an exterior case provided with an opening so that the bus bar protrudes from the opening toward the outside. Further, a capacitor is known which is configured by filling a resin for filling inside the exterior case so as to embed the capacitor element.

[0006] However, in a conventional capacitor, since the thermal expansion coefficients of the capacitor element, the bus bar, and the filling resin are different, there is a risk of the following problems occurring.

[0007] In a conventional capacitor, when the temperature of the use environment changes, the capacitor element expands or contracts, and stress may be applied to the bus bar electrically connected to the capacitor element. In this case, in a conventional capacitor, the bus bar moves so as to shift in the shear direction with respect to the filling resin around the bus bar, and peeling between the bus bar and the filling resin may occur due to the shear stress at the interface between the bus bar and the filling resin, or cracks may occur in the filling resin due to the stress (pressing force) from the bus bar moving in the shear direction.

[0008] For example, in a conventional capacitor, when used in a high-temperature environment, as the capacitor element expands, the bus bar moves so as to shift toward the opening side of the exterior case with respect to the filling resin, and peeling between the bus bar and the filling resin may occur due to the shear stress at the interface between the bus bar and the filling resin, or cracks may occur in the filling resin due to the stress (pressing force) from the bus bar moving toward the opening side of the exterior case.

[0009] In response to the above problems, in the capacitor described in Patent Document 1, the relative movement between the external connection terminal and the potting resin is restricted by the potting resin that has entered the constricted portion provided on the external connection terminal. As a result, even when the ambient temperature around the installation location of the capacitor changes, it is possible to suppress the occurrence of cracks at the portion where the external connection terminal is pulled out from the potting resin. However, in the capacitor described in Patent Document 1, there is room for improvement in further suppressing the occurrence of peeling between the external connection terminal and the potting resin, and the occurrence of cracks in the potting resin.

[0010] Also, in the electrical component described in Patent Document 2, by providing through holes in the connection terminals, the amount of expansion in the width direction of the terminals when a thermal shock is applied can be reduced. Further, due to the through holes, the deformation region of the resin due to the expansion of the terminals is also divided into a plurality of locations, making it possible to disperse the deformation, and thus it is possible to prevent the occurrence of cracks and peeling in the resin. However, in the electrical component described in Patent Document 2, there is room for improvement in further suppressing the occurrence of peeling between the connection terminals and the resin, and the occurrence of cracks in the resin.

[0011] The present invention has been made to solve the above problems, and an object thereof is to provide a capacitor capable of suppressing the occurrence of peeling between a bus bar and a potting resin, and the occurrence of cracks in the potting resin, even when the temperature of the usage environment changes.

Means for Solving the Problems

[0012] As a first aspect, the capacitor of the present invention includes a capacitor element having a dielectric body and an external electrode provided on the surface of the dielectric body, a bus bar electrically connected to the external electrode, and a bottomed cylindrical shape provided with an opening, and the capacitor element is housed therein such that the bus bar protrudes outward from the opening. An outer case, and a filling resin filled inside the outer case so as to embed the capacitor element, wherein in the bus bar, a through hole is provided in a portion located between the capacitor element and the opening, and a through direction in which the through hole extends forms an angle of less than 45° with respect to an opening surface of the opening, and the entire through hole is embedded in the filling resin.

[0013] As a second aspect, the capacitor of the present invention includes a capacitor element having a dielectric body and an external electrode provided on the surface of the dielectric body, a bus bar electrically connected to the external electrode, and a bottomed cylindrical shape provided with an opening, and the capacitor element is housed therein such that the bus bar protrudes outward from the opening. An outer case, and a filling resin filled inside the outer case so as to embed the capacitor element, wherein in the bus bar, a through hole and a protruding portion protruding from a peripheral edge of the through hole are provided in a portion located between the capacitor element and the opening, and a protruding direction in which at least a tip-side portion of the protruding portion extends forms an angle of less than 45° with respect to an opening surface of the opening, and at least a part of the through hole and the entire protruding portion are embedded in the filling resin.

Advantages of the Invention

[0014] According to the present invention, it is possible to provide a capacitor capable of suppressing the occurrence of peeling between the bus bar and the filling resin and the occurrence of cracks in the filling resin even when the temperature of the usage environment changes.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, the capacitor of the present invention will be described. Note that the present invention is not limited to the following configuration, and may be appropriately changed without departing from the gist of the present invention. Also, a combination of a plurality of the individual preferred configurations described below is also within the scope of the present invention.

[0017] Each of the embodiments shown below is illustrative, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. In the following embodiments after the second embodiment, descriptions of matters common to the first embodiment will be omitted, and different points will be mainly described. In particular, for the same operational effects due to the same configuration, they will not be sequentially mentioned for each embodiment.

[0018] In the following description, when the embodiments are not particularly distinguished, the capacitor of the present invention will simply be referred to as "the capacitor of the present invention".

[0019] Hereinafter, as an example of a capacitor element of the capacitor of the present invention, a film capacitor is shown. The capacitor of the present invention is also applicable to capacitor elements other than film capacitors.

[0020] The drawings shown below are schematic diagrams, and their dimensions, scales of aspect ratios, etc. may be different from those of actual products.

[0021] In this specification, unless otherwise specified, terms indicating the relationship between elements (e.g., "parallel", "perpendicular", etc.) and terms indicating the shape of elements do not only mean a strictly literal aspect, but also mean a substantially equivalent range, for example, a range including a difference of about several percent.

[0022] As a first aspect, the capacitor of the present invention includes a capacitor element having a dielectric body and external electrodes provided on the surface of the dielectric body, a bus bar electrically connected to the external electrodes, and a bottomed cylindrical shape provided with an opening, and the capacitor element is housed inside such that the bus bar protrudes outward from the opening. An outer case, and a filling resin filled inside the outer case so as to embed the capacitor element. In the bus bar, a through hole is provided in a portion located between the capacitor element and the opening, and the through direction in which the through hole extends forms an angle of less than 45° with respect to the opening surface of the opening, and the entire through hole is embedded in the filling resin.

[0023] [Embodiment 1] Hereinafter, an example of the first aspect of the capacitor of the present invention will be described as the capacitor of Embodiment 1 of the present invention.

[0024] FIG. 1 is a schematic diagram showing a perspective view of an example of the capacitor of Embodiment 1 of the present invention. FIG. 2 is a schematic diagram showing an example of a disassembled state of the capacitor shown in FIG. 1 (excluding the filling resin).

[0025] The capacitor 1 shown in FIGS. 1 and 2 includes a capacitor element 10, a first bus bar 20a, a second bus bar 20b, an outer case 30, and a filling resin 40.

[0026] In FIG. 1 and the like, a first direction D1, a second direction D2, and a third direction D3 are perpendicular to each other.

[0027] FIG. 3 is a schematic diagram showing a perspective view of an example of the capacitor element shown in FIGS. 1 and 2. FIG. 4 is a schematic diagram showing an example of a cross-sectional view of the capacitor element shown in FIG. 3 along the line segment a1-a2.

[0028] The capacitor element 10 shown in FIGS. 3 and 4 includes a dielectric body 11, a first external electrode 12a, and a second external electrode 12b.

[0029] The body 11 is a wound body formed by winding a first metallized film 13a and a second metallized film 13b in a stacked state in a first direction D1. That is, the capacitor element 10 is a wound type film capacitor in which the metallized films are wound in a stacked state.

[0030] Note that the capacitor element 10 may be a stacked type film capacitor (for example, a rectangular parallelepiped shape) in which the metallized films are stacked.

[0031] The body 11 has a first end face 11a and a second end face 11b that face each other in a third direction D3.

[0032] The body 11 has a side face 11c that extends in the third direction D3 so as to connect the peripheries of the first end face 11a and the second end face 11b.

[0033] In the capacitor element 10, from the viewpoint of reducing the height, when a cross section perpendicular to the winding axis direction (the third direction D3 in FIGS. 3 and 4) of the body 11 is viewed, it is preferable that the cross-sectional shape of the body 11 is a flat shape. Specifically, it is preferable that the cross-sectional shape of the body 11 is pressed into a flat shape such as an ellipse or an oblong, and the thickness is smaller than when the cross-sectional shape of the body 11 is a perfect circle.

[0034] Whether the cross-sectional shape of the body is pressed into a flat shape can be confirmed, for example, by whether there are pressing marks on the body.

[0035] The capacitor element 10 may have a cylindrical winding axis. The winding axis is disposed on the central axis of the wound first metallized film 13a and second metallized film 13b, and serves as a winding axis when winding the first metallized film 13a and the second metallized film 13b.

[0036] The first metallized film 13a has a first dielectric film 14a and a first metal layer 15a.

[0037] The first dielectric film 14a has a first main surface 14aa and a second main surface 14ab that face each other in the first direction D1.

[0038] The first metal layer 15a is provided on the first main surface 14aa of the first dielectric film 14a. Specifically, the first metal layer 15a is provided on the first main surface 14aa of the first dielectric film 14a so as to reach one side edge of the first dielectric film 14a in the third direction D3 and not reach the other side edge of the first dielectric film 14a.

[0039] The second metallized film 13b has a second dielectric film 14b and a second metal layer 15b.

[0040] The second dielectric film 14b has a first main surface 14ba and a second main surface 14bb that face each other in the first direction D1.

[0041] The second metal layer 15b is provided on the first main surface 14ba of the second dielectric film 14b. Specifically, the second metal layer 15b is provided on the first main surface 14ba of the second dielectric film 14b so as not to reach one side edge of the second dielectric film 14b and reach the other side edge of the second dielectric film 14b in the third direction D3.

[0042] In the element body 11, the end portion on the side reaching the side edge of the first dielectric film 14a in the first metal layer 15a is exposed on the first end face 11a of the element body 11, and the end portion on the side reaching the side edge of the second dielectric film 14b in the second metal layer 15b is exposed on the second end face 11b of the element body 11. Adjacent first metallization films 13a and second metallization films 13b are displaced in the third direction D3. That is, in adjacent first metallization films 13a and second metallization films 13b, the first metallization film 13a protrudes toward the first external electrode 12a side with respect to the second metallization film 13b. Also, in adjacent first metallization films 13a and second metallization films 13b, the second metallization film 13b protrudes toward the second external electrode 12b side with respect to the first metallization film 13a. In such a state, the first metal layer 15a is connected to the first external electrode 12a and is not connected to the second external electrode 12b. Also, the second metal layer 15b is connected to the second external electrode 12b and is not connected to the first external electrode 12a.

[0043] In the element body 11, since adjacent first metallization films 13a and second metallization films 13b are displaced in the third direction D3 as described above, in adjacent first dielectric films 14a and second dielectric films 14b, the first dielectric film 14a on which the first metal layer 15a is provided on the first main surface 14aa protrudes toward the first external electrode 12a side with respect to the second dielectric film 14b on which the first metal layer 15a is not provided on the main surface. Also, in adjacent first dielectric films 14a and second dielectric films 14b, the second dielectric film 14b on which the second metal layer 15b is provided on the first main surface 14ba protrudes toward the second external electrode 12b side with respect to the first dielectric film 14a on which the second metal layer 15b is not provided on the main surface.

[0044] Since the element body 11 is wound in a state where the first metallized film 13a and the second metallized film 13b are laminated in the first direction D1, it can be said that the first dielectric film 14a, the first metal layer 15a, the second dielectric film 14b, and the second metal layer 15b are included in this order in the first direction D1. Also, it can be said that the element body 11 is a wound body in which the first dielectric film 14a, the first metal layer 15a, the second dielectric film 14b, and the second metal layer 15b are laminated in this order in the first direction D1.

[0045] In the element body 11, the first main surface 14aa of the first dielectric film 14a and the second main surface 14bb of the second dielectric film 14b face each other in the first direction D1, and the second main surface 14ab of the first dielectric film 14a and the first main surface 14ba of the second dielectric film 14b face each other in the first direction D1. Thus, in the element body 11, the first metallized film 13a and the second metallized film 13b are wound in a state where they are laminated in the first direction D1. In other words, in the element body 11, the second metallized film 13b is inside the first metallized film 13a. Specifically, the first metal layer 15a is inside the first dielectric film 14a, and the second metal layer 15b is inside the second dielectric film 14b. The first metallized film 13a and the second metallized film 13b are wound in a state where they are laminated in the first direction D1. That is, in the element body 11, the first metal layer 15a and the second metal layer 15b face each other with the first dielectric film 14a or the second dielectric film 14b interposed therebetween.

[0046] The first metal layer 15a may be provided with a fuse portion. The fuse portion provided in the first metal layer 15a is, for example, a portion that connects a divided electrode portion in which a portion of the first metal layer 15a facing the second metal layer 15b is divided into a plurality of parts and an electrode portion that is a portion not facing the second metal layer 15b in the first metal layer 15a. Examples of the electrode pattern of the first metal layer 15a provided with the fuse portion include the electrode patterns disclosed in Japanese Patent Application Laid-Open No. 2004-363431, Japanese Patent Application Laid-Open No. 5-251266, and the like.

[0047] The second metal layer 15b may also be provided with a fuse portion, similar to the first metal layer 15a.

[0048] The first dielectric film 14a may contain a curable resin as a main component.

[0049] In this specification, the main component means the component with the highest weight percentage, and preferably means the component with a weight percentage higher than 50% by weight.

[0050] The curable resin may be a thermosetting resin or a photocurable resin.

[0051] In this specification, the thermosetting resin means a resin that can be cured by heat, but does not limit the curing method. Therefore, the thermosetting resin includes resins that can be cured by methods other than heat (e.g., light, electron beam, etc.) as long as they can be cured by heat. Also, depending on the material, the reaction may start due to the reactivity of the material itself, and resins that can cure without necessarily applying heat or the like from the outside are also regarded as thermosetting resins. The same applies to photocurable resins, and resins that can be cured by methods other than light (e.g., heat, etc.) are also included as long as they can be cured by light.

[0052] The curable resin preferably consists of a cured product of a first organic material having a hydroxyl group (OH group) and a second organic material having an isocyanate group (NCO group). In this case, the curable resin consists of a cured product having a urethane bond obtained by the reaction of the hydroxyl group of the first organic material and the isocyanate group of the second organic material.

[0053] The presence of the urethane bond in the dielectric film can be confirmed by analyzing with a Fourier transform infrared spectrometer (FT-IR).

[0054] When the curable resin is obtained by the above-described reaction, an uncured portion of the starting material may remain in the first dielectric film 14a. For example, the first dielectric film 14a may contain at least one of a hydroxyl group and an isocyanate group. In this case, the first dielectric film 14a may contain one of a hydroxyl group and an isocyanate group, or may contain both a hydroxyl group and an isocyanate group.

[0055] The presence of a hydroxyl group and / or an isocyanate group in the dielectric film can be confirmed by analysis with FT-IR.

[0056] Examples of the first organic material include a phenoxy resin, a polyvinyl acetal resin, a polyvinyl butyral resin, and the like.

[0057] As the first organic material, a plurality of types of organic materials may be used in combination.

[0058] Examples of the second organic material include aromatic polyisocyanates such as diphenylmethane diisocyanate (MDI) and tolylene diisocyanate (TDI), and aliphatic polyisocyanates such as hexamethylene diisocyanate (HDI). As the second organic material, at least one modified product of these polyisocyanates may be used, or a mixture of at least one of these polyisocyanates and its modified product may be used.

[0059] As the second organic material, a plurality of types of organic materials may be used in combination.

[0060] The first dielectric film 14a may contain a thermoplastic resin as a main component.

[0061] Examples of the thermoplastic resin include a polypropylene resin, a polyether sulfone resin, a polyether imide resin, a polyarylate resin, and the like.

[0062] The first dielectric film 14a may contain additives for adding various functions.

[0063] Examples of the additives include leveling agents for imparting smoothness.

[0064] The additive preferably has a functional group that reacts with a hydroxyl group and / or an isocyanate group and forms part of the crosslinked structure of the cured product. Examples of such additives include resins having at least one functional group selected from the group consisting of a hydroxyl group, an epoxy group, a silanol group, and a carboxyl group.

[0065] Similar to the first dielectric film 14a, the second dielectric film 14b may contain a thermosetting resin as a main component, may contain a photocurable resin as a main component, or may contain a thermoplastic resin as a main component. Also, similar to the first dielectric film 14a, the second dielectric film 14b may contain additives.

[0066] The compositions of the first dielectric film 14a and the second dielectric film 14b may be different from each other, but are preferably the same as each other.

[0067] The thicknesses of the first dielectric film 14a and the second dielectric film 14b are preferably 1 μm or more and 10 μm or less, and more preferably 3 μm or more and 5 μm or less.

[0068] The thicknesses of the first dielectric film 14a and the second dielectric film 14b may be different from each other, but are preferably the same as each other.

[0069] The thickness of the dielectric film is measured using an optical film thickness meter.

[0070] The first dielectric film 14a and the second dielectric film 14b are each preferably produced by forming a resin solution containing the above-described resin material into a film shape and then curing it by heat treatment.

[0071] Examples of the constituent materials of the first metal layer 15a and the second metal layer 15b include metals such as aluminum, zinc, titanium, magnesium, tin, and nickel.

[0072] The compositions of the first metal layer 15a and the second metal layer 15b may be different from each other, but are preferably the same as each other.

[0073] The thicknesses of the first metal layer 15a and the second metal layer 15b are preferably 5 nm or more and 40 nm or less.

[0074] The thicknesses of the first metal layer 15a and the second metal layer 15b may be different from each other, but are preferably the same as each other.

[0075] The thickness of the metal layer is measured by observing a cross section along the first direction of the metallization film using a transmission electron microscope (TEM).

[0076] The first metal layer 15a and the second metal layer 15b are each preferably formed by depositing the above-described metal on the main surfaces of the first dielectric film 14a and the second dielectric film 14b.

[0077] In the above, an embodiment in which the element body 11 includes two metallization films has been shown, but the element body 11 may include one metallization film. For example, the element body 11 may include a metallization film having a first dielectric film 14a on which a first metal layer 15a is provided on a first main surface 14aa and a second metal layer 15b is provided on a second main surface 14ab, and a second dielectric film 14b on which no metal layer is provided. Alternatively, the element body 11 may include a metallization film having a second dielectric film 14b on which a first metal layer 15a is provided on a second main surface 14bb and a second metal layer 15b is provided on a first main surface 14ba, and a first dielectric film 14a on which no metal layer is provided.

[0078] The first external electrode 12a is provided on the surface of the element body 11. In the examples shown in FIGS. 3 and 4, the first external electrode 12a is provided on the first end face 11a of the element body 11. The first external electrode 12a is connected to the first metal layer 15a by contacting the end portion of the first metal layer 15a exposed on the first end face 11a of the element body 11. On the other hand, the first external electrode 12a is not connected to the second metal layer 15b.

[0079] The second external electrode 12b is provided at a position on the surface of the element body 11 away from the first external electrode 12a. In the examples shown in FIGS. 3 and 4, the second external electrode 12b is provided on the second end face 11b of the element body 11. The second external electrode 12b is connected to the second metal layer 15b by contacting the end portion of the second metal layer 15b exposed on the second end face 11b of the element body 11. On the other hand, the second external electrode 12b is not connected to the first metal layer 15a.

[0080] Examples of the constituent materials of the first external electrode 12a and the second external electrode 12b include metals such as zinc, aluminum, tin, and zinc-aluminum alloys.

[0081] The compositions of the first external electrode 12a and the second external electrode 12b may be different from each other, but are preferably the same as each other.

[0082] The first external electrode 12a and the second external electrode 12b are each preferably formed by spraying a metal as described above on the first end face 11a and the second end face 11b of the element body 11.

[0083] As shown in FIG. 2, the first bus bar 20a is electrically connected to the first external electrode 12a. The first bus bar 20a may be connected to the first external electrode 12a via a joining member such as solder, or may be welded.

[0084] The first bus bar 20a has a first main surface 20aa and a second main surface 20ab that face each other in the thickness direction.

[0085] The first bus bar 20a preferably covers the surface of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided. In the example shown in FIG. 2, the first bus bar 20a covers the side surface 11c of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided (in FIG. 2, they overlap in the first direction D1). In this case, the equivalent series inductance (ESL) of the capacitor 1 is likely to decrease.

[0086] The first bus bar 20a is preferably away from the surface of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided. In the examples shown in FIGS. 5, 6, and 7 described later, the first bus bar 20a is away from the side surface 11c of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided. In this case, it is easy to ensure the insulation between the body 11 and the first bus bar 20a.

[0087] When the first bus bar 20a is away from the surface of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided, it is preferable that a filling resin 40 is filled between the first bus bar 20a and the surface of the capacitor element 10.

[0088] As shown in FIG. 2, the second bus bar 20b is electrically connected to the second external electrode 12b. The second bus bar 20b may be connected to the second external electrode 12b via a joining member such as solder, or may be welded.

[0089] Since the second bus bar 20b is electrically connected to the second external electrode 12b instead of the first external electrode 12a, it has a different polarity from the first bus bar 20a electrically connected to the first external electrode 12a.

[0090] The second bus bar 20b has a first main surface 20ba and a second main surface 20bb that face each other in the thickness direction.

[0091] The second bus bar 20b preferably covers the surface of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided. In the example shown in FIG. 2, the second bus bar 20b covers the side surface 11c of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided (in FIG. 2, they overlap in the first direction D1). In this case, the equivalent series inductance of the capacitor 1 is likely to decrease.

[0092] The second bus bar 20b is preferably separated from the surface of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided. In the examples shown in FIGS. 5, 6, and 7 described later, the second bus bar 20b is separated from the side surface 11c of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided. In this case, the insulation between the body 11 and the second bus bar 20b is likely to be ensured.

[0093] When the second bus bar 20b is separated from the surface of the capacitor element 10 where the first external electrode 12a and the second external electrode 12b are not provided, it is preferable that a filling resin 40 is filled between the second bus bar 20b and the said surface of the capacitor element 10.

[0094] The shapes of the first bus bar 20a and the second bus bar 20b are preferably plate-like. In this case, the first bus bar 20a and the second bus bar 20b may each have a shape with a part bent.

[0095] The shapes of the first bus bar 20a and the second bus bar 20b may be the same as each other or different from each other.

[0096] Examples of the constituent materials of the first bus bar 20a and the second bus bar 20b include metals such as copper, oxygen-free copper, aluminum, and alloys containing at least one of these. Among them, the constituent materials of the first bus bar 20a and the second bus bar 20b are preferably copper or oxygen-free copper. When the constituent materials of the first bus bar 20a and the second bus bar 20b are copper-based materials, for example, oxygen-free copper (copper: 99.96% by weight or more), tough pitch copper (copper: 99.90% by weight or more), phosphor-deoxidized copper (copper: 99.90% by weight or more, phosphorus: 0.015% by weight or more, 0.040% by weight or less), etc. can be used.

[0097] The constituent materials of the first bus bar 20a and the second bus bar 20b may be the same as each other or different from each other.

[0098] The thicknesses of the first bus bar 20a and the second bus bar 20b may be the same as each other or different from each other.

[0099] A part of the first bus bar 20a and the second bus bar 20b may be close to each other and overlap. In the example shown in FIG. 2, a part of the second main surface 20ab of the first bus bar 20a and the second main surface 20bb of the second bus bar 20b are close to each other and overlap. In the example shown in FIG. 2, a gap with a predetermined distance is provided between the first bus bar 20a and the second bus bar 20b, specifically, between the second main surface 20ab of the first bus bar 20a and the second main surface 20bb of the second bus bar 20b.

[0100] When a part of the first bus bar 20a and a part of the second bus bar 20b are close to and overlap each other, specifically, when a gap with a predetermined distance is provided between the first bus bar 20a and the second bus bar 20b, it is preferable that an insulating sheet (not shown) forming a laminated structure together with the first bus bar 20a and the second bus bar 20b is sandwiched between the first bus bar 20a and the second bus bar 20b. Specifically, it is preferable that the first bus bar 20a, the insulating sheet, and the second bus bar 20b overlap in this order to form a laminated structure. In this case, the insulating sheet ensures the insulation between the first bus bar 20a and the second bus bar 20b.

[0101] In this specification, the insulating sheet also includes forms such as insulating paper, insulating board, insulating film, etc.

[0102] Examples of the constituent material of the insulating sheet include resins and the like.

[0103] As shown in FIGS. 1 and 2, the exterior case 30 is a bottomed cylindrical shape provided with an opening 31. Specifically, the exterior case 30 is a bottomed cylindrical shape provided with an opening 31 at one end in the first direction D1.

[0104] In the example shown in FIGS. 1 and 2, the exterior case 30 has a bottom portion 32 facing the opening 31 in the first direction D1, and a side wall portion 33 extending in the first direction D1 from the bottom portion 32 toward the opening 31.

[0105] Inside the exterior case 30, the capacitor element 10 is housed such that the first bus bar 20a and the second bus bar 20b protrude from the opening 31 toward the outside.

[0106] The capacitor element 10 is preferably housed inside the exterior case 30 so as to be away from the inner surface of the exterior case 30.

[0107] Examples of the exterior case 30 include a resin case, a metal case, and the like.

[0108] When the outer case 30 is a resin case, examples of the resin constituting the resin case include liquid crystal polymer (LCP), polyphenylene sulfide resin, polybutylene terephthalate resin, and the like. Among them, it is preferable that the resin case contains a liquid crystal polymer.

[0109] As the liquid crystal polymer contained in the resin case, for example, a liquid crystal polymer having p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid groups in its skeleton is used. In addition to p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid groups, a liquid crystal polymer formed by polycondensation using various components such as phenol, phthalic acid, and ethylene terephthalate can also be used. When classifying liquid crystal polymers, there is also a classification method such as type I, type II, and type III, but as a material, it means the same material as the liquid crystal polymer formed from the above-described components.

[0110] Preferably, in addition to the liquid crystal polymer, the resin case further contains an inorganic filler.

[0111] As the inorganic filler contained in the resin case, a material having higher strength than the liquid crystal polymer can be used. The inorganic filler is preferably a material having a higher melting point than the liquid crystal polymer, and more preferably a material having a melting point of 680°C or higher.

[0112] The form of the inorganic filler is not particularly limited, and examples thereof include forms having a longitudinal direction such as fibrous or plate-like. As the inorganic filler in such a form, a plurality of types of inorganic materials may be used in combination. Preferably, the resin case contains at least one of a fibrous inorganic material and a plate-like inorganic material as the inorganic filler.

[0113] In this specification, when the filler is fibrous, it means a state in which, in the filler, the relationship between the longitudinal dimension in the longitudinal direction and the cross-sectional diameter in a cross-section perpendicular to the longitudinal direction is such that the longitudinal dimension / cross-sectional diameter ≥ 5 (i.e., the aspect ratio is 5:1 or more). Here, the cross-sectional diameter is the distance between the two longest points on the outer periphery of the cross-section. When the cross-sectional diameter varies in the longitudinal direction, the measurement is taken at the location where the cross-sectional diameter is maximum.

[0114] In this specification, when the filler is plate-shaped, it means a state in which, in the filler, the relationship between the cross-sectional diameter of the surface with the maximum projected area and the maximum height in the direction perpendicular to this cross-section is such that the cross-sectional diameter / maximum height ≥ 3.

[0115] It is preferable that the inorganic filler has at least a part that is oriented in the direction from the bottom portion 32 side toward the opening portion 31 side and a part that is oriented in the outer peripheral direction of the side wall portion 33 in the side wall portion 33 and is dispersed inside the outer case 30.

[0116] The size of the inorganic filler is preferably a size of 5 μm or more in diameter and 50 μm or more in length.

[0117] It is preferable that the inorganic filler is dispersed throughout the outer case 30 without agglomeration.

[0118] Examples of the inorganic filler include inorganic materials such as fibrous glass fillers, plate-shaped talc, or mica. Among them, the inorganic filler preferably contains a fibrous glass filler as a main component.

[0119] Even when the resin case contains another resin (for example, polyphenylene sulfide resin) instead of the liquid crystal polymer, it is preferable that the resin case further contains the inorganic filler as described above.

[0120] The resin case is manufactured, for example, by a method such as injection molding.

[0121] When the exterior case 30 is a metal case, examples of the metal constituting the metal case include single metals such as aluminum, magnesium, iron, stainless steel, and copper, and alloys containing at least one of these single metals. Among them, it is preferable that the metal case contains aluminum or an aluminum alloy.

[0122] The metal case is manufactured, for example, by a method such as impact molding.

[0123] As shown in FIG. 1, the filling resin 40 is filled inside the exterior case 30 so as to embed the capacitor element 10. When the filling resin 40 is filled inside the exterior case 30 in this way, the capacitor element 10 will be held inside the exterior case 30.

[0124] When the capacitor element 10 is housed inside the exterior case 30 so as to be separated from the inner surface of the exterior case 30, it is preferable that the filling resin 40 is filled between the capacitor element 10 and the exterior case 30, specifically, between the outer surface of the capacitor element 10 and the inner surface of the exterior case 30. Further, it is preferable that the filling resin 40 is filled not only between the capacitor element 10 and the exterior case 30 inside the exterior case 30 but also in the region extending from the opening 31 to the capacitor element 10.

[0125] From the viewpoint of suppressing the intrusion of moisture into the capacitor element 10, it is preferable to appropriately select a resin with low moisture permeability as the filling resin 40. Examples thereof include epoxy resin, silicone resin, and urethane resin. Examples of the curing agent for the epoxy resin include amine curing agents and imidazole curing agents.

[0126] As the filling resin 40, only the resins described above may be used, but for the purpose of improving strength, those obtained by adding a reinforcing agent to the resin may also be used. Examples of the reinforcing agent include silica and alumina.

[0127] From the perspective of suppressing the ingress of moisture into the capacitor element 10, it is preferable that the thickness of the filling resin 40 at the opening 31 is large. The thickness of the filling resin 40 at the opening 31 is preferably large enough within the range allowed by the volume (physical size) of the entire capacitor 1. Specifically, it is preferably 2 mm or more, and more preferably 4 mm or more. In particular, inside the outer case 30, by arranging the capacitor element 10 on the bottom 32 side rather than the opening 31 side, it is preferable to make the thickness of the filling resin 40 with respect to the capacitor element 10 larger on the bottom 32 side than on the opening 31 side.

[0128] The thickness of the filling resin 40 is measured using, for example, a soft X-ray device in a non-destructive state, and a length measuring device such as a caliper in a destructive state.

[0129] Regarding the relationship between the height of the outer case 30 and the height of the filling resin 40 in the first direction D1, while making the thickness of the filling resin 40 at the opening 31 as large as possible, it may reach up to the inner side position of the outer case 30, or may be about full to the brim, or may overflow slightly due to surface tension.

[0130] FIG. 5 is a schematic diagram showing a perspective view of the cross-section of the capacitor shown in FIG. 1. FIG. 6 is a schematic diagram showing the state of the capacitor shown in FIG. 5 with the filling resin removed. FIG. 7 is a schematic diagram showing a plan view of the cross-section of the capacitor shown in FIG. 6.

[0131] As shown in FIGS. 5, 6, and 7, in the first bus bar 20a, a first through hole 21aa is provided in a portion located between the capacitor element 10 and the opening 31.

[0132] The first through hole 21aa has a first end 21aaa located on the first main surface 20aa side of the first bus bar 20a and a second end 21aab located on the second main surface 20ab side of the first bus bar 20a.

[0133] As shown in FIG. 7, the penetration direction DHaa (hereinafter, also referred to as the penetration direction DHaa of the first through-hole 21aa) in which the first through-hole 21aa extends forms an angle of less than 45° with respect to the opening surface 31s of the opening 31. Specifically, the penetration direction DHaa of the first through-hole 21aa forms an angle of 0° or more and less than 45° with respect to the opening surface 31s of the opening 31.

[0134] The penetration direction DHaa of the first through-hole 21aa is defined as the direction in which a straight line connecting the center of gravity of the first end 21aaa of the first through-hole 21aa in plan view and the center of gravity of the second end 21aab of the first through-hole 21aa in plan view extends. For example, as shown in FIG. 2, when the planar shape of the first through-hole 21aa (in FIG. 2, the planar shape when viewed in plan from the third direction D3) is rectangular, the penetration direction DHaa of the first through-hole 21aa is a straight line connecting the intersection of the diagonals of the first end 21aaa (rectangle) of the first through-hole 21aa in plan view and the intersection of the diagonals of the second end 21aab (rectangle) of the first through-hole 21aa in plan view. The penetration directions of the other through-holes are also defined in the same manner.

[0135] As shown in FIGS. 5 and 6, the entire first through-hole 21aa is embedded in the filling resin 40.

[0136] In the capacitor 1, since the entire first through-hole 21aa is embedded in the filling resin 40, the first bus bar 20a is fixed by the filling resin 40 that has entered the first through-hole 21aa. Further, in the capacitor 1, since the through direction DHaa of the first through-hole 21aa forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, due to the expansion or contraction of the capacitor element 10 when the temperature of the usage environment changes, the movement of the first bus bar 20a that shifts in the shear direction with respect to the filling resin 40 (particularly, the side of the opening surface 31s of the opening 31 or the side opposite to the opening surface 31s with respect to the filling resin 40) is suppressed by the filling resin 40 that has entered the first through-hole 21aa. As a result, in the capacitor 1, the occurrence of peeling between the first bus bar 20a and the filling resin 40 due to the shear stress at the interface between the first bus bar 20a and the filling resin 40, and the occurrence of cracks in the filling resin 40 due to the stress (pressing force) from the first bus bar 20a that moves in the shear direction are suppressed.

[0137] On the other hand, if the angle formed by the through direction DHaa of the first through-hole 21aa with respect to the opening surface 31s of the opening 31 is 45° or more, particularly approaching 90°, the filling resin 40 that has entered the first through-hole 21aa becomes less likely to function to suppress the movement of the first bus bar 20a that shifts in the shear direction with respect to the filling resin 40 (particularly, the side of the opening surface 31s of the opening 31 or the side opposite to the opening surface 31s with respect to the filling resin 40). Therefore, when the through direction DHaa of the first through-hole 21aa forms an angle of 45° or more with respect to the opening surface 31s of the opening 31, the movement of the first bus bar 20a that shifts in the shear direction with respect to the filling resin 40 is less likely to be suppressed by the filling resin 40 that has entered the first through-hole 21aa.

[0138] In the capacitor described in Patent Document 1, as shown in FIGS. 1(a) and 1(b) of Patent Document 1, the through holes 11 provided in the external connection terminals 6 (external connection terminals 7) are embedded in the resin 3. However, in the capacitor described in Patent Document 1, since the through direction in which the through holes 11 extend is perpendicular to the opening surface of the opening of the case 2, due to the expansion or contraction of the capacitor element 1 when the temperature of the use environment changes, the external connection terminals 6 (external connection terminals 7) are likely to shift in the shearing direction with respect to the resin 3 (particularly, on the opening surface side or the side opposite to the opening surface of the opening of the case 2 with respect to the resin 3), and it is difficult to suppress such movement.

[0139] Also, in the electrical component described in Patent Document 2, as shown in FIG. 4 of Patent Document 2, the through holes 13 provided in the connection terminals 11 are embedded in the resin 32. However, in the electrical component described in Patent Document 2, since only a part of the through holes 13 is embedded in the resin 32, due to the expansion or contraction of the electrical element 21 when the temperature of the use environment changes, the connection terminals 11 are likely to shift in the shearing direction with respect to the resin 32 (particularly, on the opening surface side or the side opposite to the opening surface of the opening of the case 31 with respect to the resin 32), and it is difficult to suppress such movement.

[0140] From the above, in the capacitor 1, for example, compared with the capacitor described in Patent Document 1 and the electrical component described in Patent Document 2, an advantageous effect of "being able to suppress the occurrence of peeling between the bus bar and the filling resin and the occurrence of cracks in the filling resin even when the temperature of the use environment changes" can be obtained.

[0141] From the viewpoint of enhancing the above effect of the capacitor 1, as shown in FIG. 7, it is preferable that the through direction DHaa of the first through hole 21aa is parallel to the opening surface 31s of the opening 31.

[0142] In the example shown in FIG. 7, the penetration direction DHaa of the first through hole 21aa is parallel to the third direction D3. Also, in the example shown in FIG. 7, the opening surface 31s of the opening 31 is parallel to the third direction D3. Therefore, in the example shown in FIG. 7, the penetration direction DHaa of the first through hole 21aa is parallel to the opening surface 31s of the opening 31. That is, in the example shown in FIG. 7, the penetration direction DHaa of the first through hole 21aa forms an angle of 0° with respect to the opening surface 31s of the opening 31.

[0143] Note that the penetration direction DHaa of the first through hole 21aa may form an angle greater than 0° and less than 45° with respect to the opening surface 31s of the opening 31.

[0144] If the penetration direction DHaa of the first through hole 21aa forms an angle less than 45° with respect to the opening surface 31s of the opening 31, it may be parallel to the thickness direction of the first bus bar 20a (in FIG. 7, the third direction D3), or may not be parallel to the thickness direction of the first bus bar 20a (it may be inclined with respect to the thickness direction of the first bus bar 20a).

[0145] When the penetration direction DHaa of the first through hole 21aa is parallel to the thickness direction of the first bus bar 20a, it is perpendicular to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a.

[0146] When the penetration direction DHaa of the first through hole 21aa is not parallel to the thickness direction of the first bus bar 20a (when it is inclined with respect to the thickness direction of the first bus bar 20a), it is not perpendicular to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a (it is inclined with respect to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a).

[0147] As shown in FIG. 7, the surface of the first bus bar 20a on which the first through hole 21aa (similarly for the first through hole 21ab described later) is provided is preferably perpendicular to the opening surface 31s of the opening 31.

[0148] In the example shown in FIG. 7, the first main surface 20aa and the second main surface 20ab of the first bus bar 20a in which the first through hole 21aa is provided are perpendicular to the opening surface 31s of the opening 31.

[0149] In addition, if the through direction DHaa of the first through hole 21aa forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, the first main surface 20aa and the second main surface 20ab of the first bus bar 20a in which the first through hole 21aa is provided do not have to be perpendicular to the opening surface 31s of the opening 31.

[0150] As shown in FIGS. 5, 6, and 7, in the first bus bar 20a, a first through hole 21ab is further provided in a portion located between the capacitor element 10 and the opening 31.

[0151] The first through hole 21ab has a first end 21aba located on the first main surface 20aa side of the first bus bar 20a and a second end 21abb located on the second main surface 20ab side of the first bus bar 20a.

[0152] As shown in FIG. 7, the through direction DHab in which the first through hole 21ab extends (hereinafter, also referred to as the through direction DHab of the first through hole 21ab) forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0153] As shown in FIGS. 5 and 6, the entire first through hole 21ab is embedded in the filling resin 40.

[0154] In the capacitor 1, since the through direction DHab of the first through hole 21ab forms an angle of less than 45° with respect to the opening surface 31s of the opening 31 and the entire first through hole 21ab is embedded in the filling resin 40, in the same manner as the above-described mechanism, even when the temperature of the usage environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0155] The features of the first through-hole 21ab (for example, the through direction DHab of the first through-hole 21ab) are the same as those of the first through-hole 21aa, including the points described above.

[0156] As shown in FIGS. 5, 6, and 7, in the second bus bar 20b, a second through-hole 21ba is provided in a portion located between the capacitor element 10 and the opening 31.

[0157] The second through-hole 21ba has a first end 21baa located on the first main surface 20ba side of the second bus bar 20b and a second end 21bab located on the second main surface 20bb side of the second bus bar 20b.

[0158] As shown in FIG. 7, the through direction DHba in which the second through-hole 21ba extends (hereinafter, also referred to as the through direction DHba of the second through-hole 21ba) forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0159] As shown in FIGS. 5 and 6, the entire second through-hole 21ba is embedded in the filling resin 40.

[0160] In the capacitor 1, since the through direction DHba of the second through-hole 21ba forms an angle of less than 45° with respect to the opening surface 31s of the opening 31 and the entire second through-hole 21ba is embedded in the filling resin 40, in the same manner as the mechanism described above, even when the temperature of the usage environment changes, the occurrence of peeling between the second bus bar 20b and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0161] The features of the second through-hole 21ba (for example, the through direction DHba of the second through-hole 21ba) are the same as those of the first through-hole 21aa, including the points described above.

[0162] As shown in FIG. 7, the surface of the second bus bar 20b on which the second through-hole 21ba (the same applies to the second through-hole 21bb described later) is provided is preferably perpendicular to the opening surface 31s of the opening 31.

[0163] In the example shown in FIG. 7, the first main surface 20ba and the second main surface 20bb of the second bus bar 20b in which the second through hole 21ba is provided are perpendicular to the opening surface 31s of the opening 31.

[0164] Note that if the through direction DHba of the second through hole 21ba forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, the first main surface 20ba and the second main surface 20bb of the second bus bar 20b in which the second through hole 21ba is provided do not have to be perpendicular to the opening surface 31s of the opening 31.

[0165] As shown in FIGS. 5, 6, and 7, in the second bus bar 20b, a second through hole 21bb is provided in a portion located between the capacitor element 10 and the opening 31.

[0166] The second through hole 21bb has a first end portion 21bba located on the first main surface 20ba side of the second bus bar 20b and a second end portion 21bbb located on the second main surface 20bb side of the second bus bar 20b.

[0167] As shown in FIG. 7, the through direction DHbb in which the second through hole 21bb extends (hereinafter, also referred to as the through direction DHbb of the second through hole 21bb) forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0168] As shown in FIGS. 5 and 6, the entire second through hole 21bb is embedded in the filling resin 40.

[0169] In the capacitor 1, since the through direction DHbb of the second through hole 21bb forms an angle of less than 45° with respect to the opening surface 31s of the opening 31 and the entire second through hole 21bb is embedded in the filling resin 40, in the same manner as the mechanism described above, even when the temperature of the usage environment changes, the occurrence of peeling between the second bus bar 20b and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0170] The features of the second through-hole 21bb (for example, the penetration direction DHbb of the second through-hole 21bb) are the same as those of the first through-hole 21aa, including the points described above.

[0171] As shown in FIGS. 2, 6, and 7, in the region where the first bus bar 20a and the second bus bar 20b overlap, it is preferable that at least a part of the first through-hole 21aa and at least a part of the second through-hole 21ba overlap and communicate with each other. In this case, in the capacitor 1, since the first bus bar 20a and the second bus bar 20b are more firmly fixed by the filling resin 40 that enters the first through-hole 21aa and the second through-hole 21ba, even if the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40, the occurrence of peeling between the second bus bar 20b and the filling resin 40, and the occurrence of cracks in the filling resin 40 are more suppressed.

[0172] In the example shown in FIGS. 2, 6, and 7, in the region where the first bus bar 20a and the second bus bar 20b overlap, the whole of the first through-hole 21aa and the whole of the second through-hole 21ba overlap and communicate with each other. However, it is also possible that the whole of the first through-hole 21aa and a part of the second through-hole 21ba overlap and communicate with each other, or a part of the first through-hole 21aa and the whole of the second through-hole 21ba overlap and communicate with each other, or a part of the first through-hole 21aa and a part of the second through-hole 21ba overlap and communicate with each other.

[0173] As shown in FIGS. 2, 6, and 7, in the region where the first bus bar 20a and the second bus bar 20b overlap, it is preferable that at least a part of the first through-hole 21ab and at least a part of the second through-hole 21bb overlap and communicate with each other. In this case, in the capacitor 1, since the first bus bar 20a and the second bus bar 20b are more firmly fixed by the filling resin 40 that enters the first through-hole 21ab and the second through-hole 21bb, even if the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40, the occurrence of peeling between the second bus bar 20b and the filling resin 40, and the occurrence of cracks in the filling resin 40 are more suppressed.

[0174] In the examples shown in FIGS. 2, 6, and 7, in the region where the first bus bar 20a and the second bus bar 20b overlap, the entire first through hole 21ab and the entire second through hole 21bb overlap and communicate with each other. However, the entire first through hole 21ab and a part of the second through hole 21bb may overlap and communicate with each other, or a part of the first through hole 21ab and the entire second through hole 21bb may overlap and communicate with each other, or a part of the first through hole 21ab and a part of the second through hole 21bb may overlap and communicate with each other.

[0175] The planar shapes (in FIG. 2, the planar shapes when viewed in a plan view from the third direction D3) of the first through hole 21aa, the first through hole 21ab, the second through hole 21ba, and the second through hole 21bb are not particularly limited, and examples include rectangular shapes such as rectangular and square shapes, circular shapes, elliptical shapes, and shapes obtained by combining these.

[0176] The planar shapes of the first through hole 21aa, the first through hole 21ab, the second through hole 21ba, and the second through hole 21bb may be the same as each other, may be different from each other, or may be partially different.

[0177] When the first through hole 21aa and the second through hole 21ba overlap and communicate with each other, the planar shapes of the first through hole 21aa and the second through hole 21ba are preferably the same as each other.

[0178] When the first through hole 21ab and the second through hole 21bb overlap and communicate with each other, the planar shapes of the first through hole 21ab and the second through hole 21bb are preferably the same as each other.

[0179] In the first aspect of the capacitor of the present invention, it is sufficient that the feature that "the penetrating direction in which the through hole extends forms an angle of less than 45° with respect to the opening surface of the opening, and the entire through hole is embedded in the filling resin" is satisfied for at least one through hole. For example, in the capacitor 1, it is sufficient that the above feature is satisfied for at least one through hole selected from the group consisting of the first through hole 21aa, the first through hole 21ab, the second through hole 21ba, and the second through hole 21bb.

[0180] In the first bus bar 20a, a through hole may or may not be provided in a portion protruding from the opening 31 of the exterior case 30 toward the outside, as shown in FIG. 1 and the like.

[0181] In the second bus bar 20b, a through hole may or may not be provided in a portion protruding from the opening 31 of the exterior case 30 toward the outside, as shown in FIG. 1 and the like.

[0182] When a through hole is provided in at least one of the first bus bar 20a and the second bus bar 20b in a portion protruding from the opening 31 of the exterior case 30 toward the outside, it is preferable that the through hole is provided outside the filling resin 40 (not embedded in the filling resin 40).

[0183] The first aspect of the capacitor of the present invention is not limited to the above embodiment, and various applications and modifications can be made within the scope of the present invention regarding the configuration of the capacitor, manufacturing conditions, and the like.

[0184] For example, in the first aspect of the capacitor of the present invention, the number of capacitor elements housed inside one exterior case is not particularly limited. That is, in the first aspect of the capacitor of the present invention, one capacitor element may be housed inside one exterior case, or a plurality of capacitor elements (two capacitor elements in the example shown in FIG. 1 and the like) may be housed.

[0185] In addition, in the first aspect of the capacitor of the present invention, the number of through holes provided in the portion located between the capacitor element and the opening in one bus bar is not particularly limited. That is, in the first aspect of the capacitor of the present invention, one through hole may be provided in the portion located between the capacitor element and the opening in one bus bar, or a plurality of through holes (two in the example shown in FIG. 1 etc.) may be provided.

[0186] As a second aspect, the capacitor of the present invention includes a capacitor element having a body and an external electrode provided on the surface of the body, a bus bar electrically connected to the external electrode, and a bottomed cylindrical shape with an opening provided therein. The capacitor element is housed inside such that the bus bar protrudes outward from the opening, and a filling resin filled inside the outer case so as to embed the capacitor element. In the bus bar, a through hole and a protruding portion protruding from the periphery of the through hole are provided in the portion located between the capacitor element and the opening. The protruding direction in which at least the tip side portion of the protruding portion extends forms an angle of less than 45° with respect to the opening surface of the opening, and at least a part of the through hole and the entire protruding portion are embedded in the filling resin.

[0187] The second aspect of the capacitor of the present invention is the same as the first aspect of the capacitor of the present invention except for the points that "in the bus bar, a through hole and a protruding portion protruding from the periphery of the through hole are provided in the portion located between the capacitor element and the opening. The protruding direction in which at least the tip side portion of the protruding portion extends forms an angle of less than 45° with respect to the opening surface of the opening, and at least a part of the through hole and the entire protruding portion are embedded in the filling resin."

[0188] [Embodiment 2] Hereinafter, an example of the second aspect of the capacitor of the present invention will be described as the capacitor of Embodiment 2 of the present invention.

[0189] In the capacitor according to Embodiment 2 of the present invention, the entire through-hole and the entire protruding portion are embedded in the filling resin.

[0190] FIG. 8 is a schematic diagram showing a perspective view of an example of the capacitor according to Embodiment 2 of the present invention. FIG. 9 is a schematic diagram showing an example of a state in which the capacitor (excluding the filling resin) shown in FIG. 8 is disassembled.

[0191] The capacitor 2 shown in FIGS. 8 and 9 includes a capacitor element 10, a first bus bar 20a, a second bus bar 20b, an exterior case 30, and a filling resin 40.

[0192] In the capacitor 2, the features of each member of the capacitor element 10, the first bus bar 20a, the second bus bar 20b, the exterior case 30, and the filling resin 40 are the same as those of each member described above in the capacitor 1, except for the following points. In the example shown in FIG. 9, in the region where the first bus bar 20a and the second bus bar 20b overlap, a gap with a predetermined distance is provided between the first bus bar 20a and the second bus bar 20b, specifically, between the second main surface 20ab of the first bus bar 20a and the second main surface 20bb of the second bus bar 20b.

[0193] FIG. 10 is a schematic diagram showing a perspective view of a cross section of the capacitor shown in FIG. 8. FIG. 11 is a schematic diagram showing a state in which the filling resin is removed from the capacitor shown in FIG. 10. FIG. 12 is a schematic diagram showing a plan view of a cross section of the capacitor shown in FIG. 11.

[0194] As shown in FIGS. 10, 11, and 12, in the first bus bar 20a, a first through-hole 21aa and a first protruding portion 25aa protruding from the periphery of the first through-hole 21aa are provided in a portion located between the capacitor element 10 and the opening 31.

[0195] As shown in FIG. 12, the protruding direction DPaa (hereinafter also referred to as the protruding direction DPaa of the first protruding portion 25aa) in which at least the tip-side portion of the first protruding portion 25aa extends forms an angle of less than 45° with respect to the opening surface 31s of the opening 31. Specifically, the protruding direction DPaa of the first protruding portion 25aa forms an angle of 0° or more and less than 45° with respect to the opening surface 31s of the opening 31.

[0196] The protruding direction DPaa of the first protruding portion 25aa is determined in the direction in which the tip-side portion of the first protruding portion 25aa substantially extends in the path in which the first protruding portion 25aa extends from the base (peripheral side of the first through-hole 21aa) toward the tip (opposite side of the peripheral edge of the first through-hole 21aa). For example, when the first protruding portion 25aa extends in a planar shape (linear when viewed in cross-section) from the base toward the tip, the protruding direction DPaa of the first protruding portion 25aa is determined in the direction in which the entire first protruding portion 25aa including the tip-side portion of the first protruding portion 25aa extends. Also, when the first protruding portion 25aa extends in a non-planar manner (non-linear manner when viewed in cross-section) from the base toward the tip, the protruding direction DPaa of the first protruding portion 25aa is determined in the direction in which the tip-side portion of the first protruding portion 25aa extends. The protruding directions of the other protruding portions are also determined in the same manner.

[0197] As shown in FIGS. 10 and 11, the entire first through-hole 21aa and the entire first protruding portion 25aa are embedded in the filling resin 40.

[0198] In the capacitor 2, since the entire first through-hole 21aa is embedded in the filling resin 40, the first bus bar 20a is fixed by the filling resin 40 that has entered the first through-hole 21aa. Also, in the capacitor 2, since the entire first protrusion 25aa is embedded in the filling resin 40, the first bus bar 20a is fixed by the filling resin 40 that has engaged with the first protrusion 25aa. Further, in the capacitor 2, since the protruding direction DPaa of the first protrusion 25aa forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, due to the expansion or contraction of the capacitor element 10 when the temperature of the usage environment changes, the movement of the first bus bar 20a that shifts in the shearing direction with respect to the filling resin 40 (particularly, the side of the opening surface 31s of the opening 31 or the side opposite to the opening surface 31s with respect to the filling resin 40) is suppressed by the filling resin 40 that has entered the first through-hole 21aa and further by the filling resin 40 that has engaged with the first protrusion 25aa. As a result, in the capacitor 2, the occurrence of peeling between the first bus bar 20a and the filling resin 40 due to the shearing stress at the interface between the first bus bar 20a and the filling resin 40 and the occurrence of cracks in the filling resin 40 due to the stress (pressing force) from the first bus bar 20a that moves in the shearing direction are suppressed.

[0199] From the above, in the capacitor 2, similar to the capacitor 1, for example, compared with the capacitor described in Patent Document 1 and the electrical component described in Patent Document 2, an advantageous effect of "being able to suppress the occurrence of peeling between the bus bar and the filling resin and the occurrence of cracks in the filling resin even when the temperature of the usage environment changes" can be obtained.

[0200] From the viewpoint of enhancing the above effect of the capacitor 2, as shown in FIG. 12, the protruding direction DPaa of the first protrusion 25aa is preferably parallel to the opening surface 31s of the opening 31.

[0201] In the example shown in FIG. 12, the protruding direction DPaa of the first protruding portion 25aa is parallel to the third direction D3. Also, in the example shown in FIG. 12, the opening surface 31s of the opening 31 is parallel to the third direction D3. Therefore, in the example shown in FIG. 12, the protruding direction DPaa of the first protruding portion 25aa is parallel to the opening surface 31s of the opening 31. That is, in the example shown in FIG. 12, the protruding direction DPaa of the first protruding portion 25aa forms an angle of 0° with respect to the opening surface 31s of the opening 31.

[0202] Note that the protruding direction DPaa of the first protruding portion 25aa may form an angle greater than 0° and less than 45° with respect to the opening surface 31s of the opening 31.

[0203] From the viewpoint of enhancing the above-described effect by the capacitor 2, as shown in FIG. 12, it is preferable that the penetrating direction DHaa of the first through hole 21aa forms an angle of less than 45° with respect to the opening surface 31s of the opening 31. Specifically, it is preferable that the penetrating direction DHaa of the first through hole 21aa forms an angle of 0° or more and less than 45° with respect to the opening surface 31s of the opening 31.

[0204] From the viewpoint of enhancing the above-described effect by the capacitor 2, as shown in FIG. 12, it is more preferable that the penetrating direction DHaa of the first through hole 21aa is parallel to the opening surface 31s of the opening 31.

[0205] In the example shown in FIG. 12, the penetrating direction DHaa of the first through hole 21aa is parallel to the third direction D3. Also, in the example shown in FIG. 12, the opening surface 31s of the opening 31 is parallel to the third direction D3. Therefore, in the example shown in FIG. 12, the penetrating direction DHaa of the first through hole 21aa is parallel to the opening surface 31s of the opening 31. That is, in the example shown in FIG. 12, the penetrating direction DHaa of the first through hole 21aa forms an angle of 0° with respect to the opening surface 31s of the opening 31.

[0206] Note that the penetrating direction DHaa of the first through hole 21aa may form an angle greater than 0° and less than 45° with respect to the opening surface 31s of the opening 31.

[0207] The through direction DHaa of the first through hole 21aa may be parallel to the thickness direction of the first bus bar 20a (in FIG. 12, the third direction D3), or may not be parallel to the thickness direction of the first bus bar 20a (it may be inclined with respect to the thickness direction of the first bus bar 20a).

[0208] When the through direction DHaa of the first through hole 21aa is parallel to the thickness direction of the first bus bar 20a, it is perpendicular to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a.

[0209] When the through direction DHaa of the first through hole 21aa is not parallel to the thickness direction of the first bus bar 20a (when it is inclined with respect to the thickness direction of the first bus bar 20a), it is not perpendicular to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a (it is inclined with respect to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a).

[0210] As shown in FIG. 12, in the first bus bar 20a, the surface on which the first through hole 21aa (similarly for the first through hole 21ab described later) is provided is preferably perpendicular to the opening surface 31s of the opening 31.

[0211] In the example shown in FIG. 12, the first main surface 20aa and the second main surface 20ab of the first bus bar 20a on which the first through hole 21aa is provided are perpendicular to the opening surface 31s of the opening 31.

[0212] Note that the first main surface 20aa and the second main surface 20ab of the first bus bar 20a on which the first through hole 21aa is provided may not be perpendicular to the opening surface 31s of the opening 31.

[0213] As shown in FIGS. 10, 11, and 12, in the first bus bar 20a, a first through hole 21ab and a first protruding portion 25ab protruding from the periphery of the first through hole 21ab are further provided in a portion located between the capacitor element 10 and the opening 31.

[0214] As shown in FIG. 12, the protruding direction DPab in which at least the tip-side portion of the first protruding portion 25ab extends (hereinafter, also referred to as the protruding direction DPab of the first protruding portion 25ab) forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0215] As shown in FIGS. 10 and 11, the entire first through-hole 21ab and the entire first protruding portion 25ab are embedded in the filling resin 40.

[0216] In the capacitor 2, since the protruding direction DPab of the first protruding portion 25ab forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, and the entire first through-hole 21ab and the entire first protruding portion 25ab are embedded in the filling resin 40, similar to the above-described mechanism, even when the temperature of the usage environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0217] The features of the first through-hole 21ab (for example, the penetrating direction DHab of the first through-hole 21ab) are the same as the features of the first through-hole 21aa including the above-described points.

[0218] The features of the first protruding portion 25ab (for example, the protruding direction DPab of the first protruding portion 25ab) are the same as the features of the first protruding portion 25aa including the above-described points.

[0219] As shown in FIGS. 10, 11, and 12, in the second bus bar 20b, a second through-hole 21ba and a second protruding portion 25ba protruding from the periphery of the second through-hole 21ba are provided in a portion located between the capacitor element 10 and the opening 31.

[0220] As shown in FIG. 12, the protruding direction DPba in which at least the tip-side portion of the second protruding portion 25ba extends (hereinafter, also referred to as the protruding direction DPba of the second protruding portion 25ba) forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0221] As shown in FIGS. 10 and 11, the entire second through-hole 21ba and the entire second protrusion 25ba are embedded in the filling resin 40.

[0222] In the capacitor 2, since the protruding direction DPba of the second protrusion 25ba forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, and the entire second through-hole 21ba and the entire second protrusion 25ba are embedded in the filling resin 40, in the same manner as the above-described mechanism, even when the temperature of the usage environment changes, the occurrence of peeling between the second bus bar 20b and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0223] The features of the second through-hole 21ba (for example, the penetrating direction DHba of the second through-hole 21ba) are the same as the features of the first through-hole 21aa including the above-described points.

[0224] The features of the second protrusion 25ba (for example, the protruding direction DPba of the second protrusion 25ba) are the same as the features of the first protrusion 25aa including the above-described points.

[0225] As shown in FIG. 12, the surface of the second bus bar 20b where the second through-hole 21ba (the same applies to the second through-hole 21bb described later) is provided is preferably perpendicular to the opening surface 31s of the opening 31.

[0226] In the example shown in FIG. 12, the first main surface 20ba and the second main surface 20bb of the second bus bar 20b where the second through-hole 21ba is provided are perpendicular to the opening surface 31s of the opening 31.

[0227] Note that the first main surface 20ba and the second main surface 20bb of the second bus bar 20b where the second through-hole 21ba is provided do not have to be perpendicular to the opening surface 31s of the opening 31.

[0228] As shown in FIGS. 10, 11, and 12, in the second bus bar 20b, a second through hole 21bb and a second protruding portion 25bb protruding from the periphery of the second through hole 21bb are further provided in a portion located between the capacitor element 10 and the opening 31.

[0229] As shown in FIG. 12, the protruding direction DPbb (hereinafter, also referred to as the protruding direction DPbb of the second protruding portion 25bb) in which at least the tip-side portion of the second protruding portion 25bb extends forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0230] As shown in FIGS. 10 and 11, the entire second through hole 21bb and the entire second protruding portion 25bb are embedded in the filling resin 40.

[0231] In the capacitor 2, since the protruding direction DPbb of the second protruding portion 25bb forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, and the entire second through hole 21bb and the entire second protruding portion 25bb are embedded in the filling resin 40, in the same manner as the above-described mechanism, even when the temperature of the use environment changes, the occurrence of peeling between the second bus bar 20b and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0232] The characteristics of the second through hole 21bb (for example, the penetrating direction DHbb of the second through hole 21bb) are the same as the characteristics of the first through hole 21aa including the above-described points.

[0233] The characteristics of the second protruding portion 25bb (for example, the protruding direction DPbb of the second protruding portion 25bb) are the same as the characteristics of the first protruding portion 25aa including the above-described points.

[0234] As shown in FIGS. 9, 11, and 12, in the region where the first bus bar 20a and the second bus bar 20b overlap, it is preferable that at least a part of the first through hole 21aa and at least a part of the second through hole 21ba overlap and communicate with each other. In this case, in the capacitor 2, since the first bus bar 20a and the second bus bar 20b are more firmly fixed by the filling resin 40 that has entered the first through hole 21aa and the second through hole 21ba, even if the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40, the occurrence of peeling between the second bus bar 20b and the filling resin 40, and the occurrence of cracks in the filling resin 40 are more suppressed.

[0235] In the example shown in FIGS. 9, 11, and 12, in the region where the first bus bar 20a and the second bus bar 20b overlap, the whole of the first through hole 21aa and the whole of the second through hole 21ba overlap and communicate with each other. However, the whole of the first through hole 21aa and a part of the second through hole 21ba may overlap and communicate with each other, or a part of the first through hole 21aa and the whole of the second through hole 21ba may overlap and communicate with each other, or a part of the first through hole 21aa and a part of the second through hole 21ba may overlap and communicate with each other.

[0236] As shown in FIGS. 9, 11, and 12, in the region where the first bus bar 20a and the second bus bar 20b overlap, it is preferable that at least a part of the first through hole 21ab and at least a part of the second through hole 21bb overlap and communicate with each other. In this case, in the capacitor 2, since the first bus bar 20a and the second bus bar 20b are more firmly fixed by the filling resin 40 that has entered the first through hole 21ab and the second through hole 21bb, even if the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40, the occurrence of peeling between the second bus bar 20b and the filling resin 40, and the occurrence of cracks in the filling resin 40 are more suppressed.

[0237] In the examples shown in FIGS. 9, 11, and 12, in the region where the first bus bar 20a and the second bus bar 20b overlap, the entire first through hole 21ab and the entire second through hole 21bb overlap and communicate with each other. However, the entire first through hole 21ab and a part of the second through hole 21bb may overlap and communicate with each other, or a part of the first through hole 21ab and the entire second through hole 21bb may overlap and communicate with each other, or a part of the first through hole 21ab and a part of the second through hole 21bb may overlap and communicate with each other.

[0238] As shown in FIGS. 9, 11, and 12, it is preferable that the first protrusion 25aa and the second protrusion 25ba extend in opposite directions toward their respective tips. In this case, in the capacitor 2, the first bus bar 20a and the second bus bar 20b are more firmly fixed by the filling resin 40 that engages with each of the first protrusion 25aa and the second protrusion 25ba. Therefore, even when the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40, the occurrence of peeling between the second bus bar 20b and the filling resin 40, and the occurrence of cracks in the filling resin 40 are more suppressed.

[0239] As shown in FIGS. 9, 11, and 12, it is preferable that the first protrusion 25ab and the second protrusion 25bb extend in opposite directions toward their respective tips. In this case, in the capacitor 2, the first bus bar 20a and the second bus bar 20b are more firmly fixed by the filling resin 40 that engages with each of the first protrusion 25ab and the second protrusion 25bb. Therefore, even when the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40, the occurrence of peeling between the second bus bar 20b and the filling resin 40, and the occurrence of cracks in the filling resin 40 are more suppressed.

[0240] At least one of the first protrusion 25aa and the first protrusion 25ab is preferably integrated with the first bus bar 20a. That is, at least one of the first protrusion 25aa and the first protrusion 25ab preferably constitutes a part of the first bus bar 20a.

[0241] In this specification, when two elements are integrated, it means that there is no interface between the elements, for example, it means a state where the boundary between the elements cannot be discriminated.

[0242] Note that at least one of the first protrusions 25aa and 25ab does not have to be integrated with the first bus bar 20a. For example, at least one of the first protrusions 25aa and 25ab may be joined or adhered to the first bus bar 20a as a separate member independent from the first bus bar 20a.

[0243] It is preferable that at least one of the second protrusions 25ba and 25bb is integrated with the second bus bar 20b. That is, it is preferable that at least one of the second protrusions 25ba and 25bb constitutes a part of the second bus bar 20b.

[0244] Note that at least one of the second protrusions 25ba and 25bb does not have to be integrated with the second bus bar 20b. For example, at least one of the second protrusions 25ba and 25bb may be joined or adhered to the second bus bar 20b as a separate member independent from the second bus bar 20b.

[0245] The planar shapes of the first protrusions 25aa, 25ab, the second protrusions 25ba, and 25bb (in FIG. 9, the planar shape when viewed in plan from the first direction D1) are not particularly limited, and examples include rectangular shapes such as rectangular and square shapes, circular shapes, elliptical shapes, and shapes combining these.

[0246] The planar shapes of the first protrusions 25aa, 25ab, the second protrusions 25ba, and 25bb may be the same as each other, may be different from each other, or may be partially different.

[0247] [Embodiment 3] Hereinafter, another example of the second aspect of the capacitor of the present invention will be described as the capacitor of Embodiment 3 of the present invention.

[0248] In the capacitor according to Embodiment 3 of the present invention, unlike the capacitor according to Embodiment 2 of the present invention, a part of the through hole and the entire protruding portion are embedded in the filling resin.

[0249] The capacitor according to Embodiment 3 of the present invention is the same as the capacitor according to Embodiment 2 of the present invention except for the above points.

[0250] FIG. 13 is a schematic diagram showing a perspective view of an example of the capacitor according to Embodiment 3 of the present invention. FIG. 14 is a schematic diagram showing an example of a state in which the capacitor (excluding the filling resin) shown in FIG. 13 is disassembled.

[0251] The capacitor 3 shown in FIGS. 13 and 14 includes a capacitor element 10, a first bus bar 20a, a second bus bar 20b, an exterior case 30, and a filling resin 40.

[0252] The features of each member of the capacitor element 10, the first bus bar 20a, the second bus bar 20b, the exterior case 30, and the filling resin 40 in the capacitor 3 are the same as the features of the above-described respective members in the capacitor 1 except for the following points. In the example shown in FIGS. 13 and 14, in the region where the first bus bar 20a and the second bus bar 20b overlap, a gap with a predetermined distance is provided between the first bus bar 20a and the second bus bar 20b, specifically, between the second main surface 20ab of the first bus bar 20a and the second main surface 20bb of the second bus bar 20b.

[0253] FIG. 15 is a schematic diagram showing a perspective view of a cross section of the capacitor shown in FIG. 13. FIG. 16 is a schematic diagram showing a state in which the filling resin is removed from the capacitor shown in FIG. 15. FIG. 17 is a schematic diagram showing a state in which a cross section of the capacitor shown in FIG. 16 is viewed in a plan view.

[0254] As shown in FIGS. 15, 16, and 17, in the first bus bar 20a, a first through hole 21aa and a first protruding portion 25aa protruding from the periphery of the first through hole 21aa are provided in a portion located between the capacitor element 10 and the opening 31.

[0255] As shown in FIG. 17, the protruding direction DPaa of the first protruding portion 25aa forms an angle of less than 45° with respect to the opening surface 31s of the opening 31. Specifically, the protruding direction DPaa of the first protruding portion 25aa forms an angle of 0° or more and less than 45° with respect to the opening surface 31s of the opening 31.

[0256] As shown in FIGS. 15 and 16, a part of the first through hole 21aa and the whole of the first protruding portion 25aa are embedded in the filling resin 40.

[0257] In the capacitor 3, since a part of the first through hole 21aa is embedded in the filling resin 40, the length of the interface between the first bus bar 20a and the filling resin 40 becomes smaller compared with the capacitor 2, so the stress caused by the difference in the thermal expansion coefficients of the first bus bar 20a and the filling resin 40 is reduced. As a result, in the capacitor 3, the occurrence of peeling between the first bus bar 20a and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed compared with the capacitor 2.

[0258] In addition, in the electrical component described in Patent Document 2, as shown in FIG. 4 of Patent Document 2, although only a part of the through hole 13 is embedded in the resin 32, since there is no protruding portion that protrudes from the periphery of the through hole 13 and is entirely embedded in the resin 32, when the temperature of the use environment changes, due to the expansion or contraction of the electrical element 21, the movement of the connection terminal 11 that shifts in the shearing direction with respect to the resin 32 (particularly, the opening surface side or the side opposite to the opening surface of the opening of the case 31 with respect to the resin 32) is difficult to be suppressed.

[0259] From the above, in the capacitor 3, similar to the capacitors 1 and 2, for example, compared with the capacitor described in Patent Document 1 and the electrical component described in Patent Document 2, an advantageous effect that "even when the temperature of the usage environment changes, it is possible to suppress the occurrence of peeling between the bus bar and the filling resin and the occurrence of cracks in the filling resin" can be obtained.

[0260] From the viewpoint of enhancing the above effect by the capacitor 3, as shown in FIG. 17, it is preferable that the protruding direction DPaa of the first protruding portion 25aa is parallel to the opening surface 31s of the opening 31.

[0261] In the example shown in FIG. 17, the protruding direction DPaa of the first protruding portion 25aa is parallel to the third direction D3. Also, in the example shown in FIG. 17, the opening surface 31s of the opening 31 is parallel to the third direction D3. Therefore, in the example shown in FIG. 17, the protruding direction DPaa of the first protruding portion 25aa is parallel to the opening surface 31s of the opening 31. That is, in the example shown in FIG. 17, the protruding direction DPaa of the first protruding portion 25aa forms an angle of 0° with respect to the opening surface 31s of the opening 31.

[0262] Note that the protruding direction DPaa of the first protruding portion 25aa may form an angle greater than 0° and less than 45° with respect to the opening surface 31s of the opening 31.

[0263] From the viewpoint of enhancing the above effect by the capacitor 3, as shown in FIG. 17, it is preferable that the penetrating direction DHaa of the first through hole 21aa forms an angle less than 45° with respect to the opening surface 31s of the opening 31. Specifically, it is preferable that the penetrating direction DHaa of the first through hole 21aa forms an angle of 0° or more and less than 45° with respect to the opening surface 31s of the opening 31.

[0264] From the viewpoint of enhancing the above effect by the capacitor 3, as shown in FIG. 17, it is more preferable that the penetrating direction DHaa of the first through hole 21aa is parallel to the opening surface 31s of the opening 31.

[0265] In the example shown in FIG. 17, the penetration direction DHaa of the first through-hole 21aa is parallel to the third direction D3. Also, in the example shown in FIG. 17, the opening surface 31s of the opening 31 is parallel to the third direction D3. Therefore, in the example shown in FIG. 17, the penetration direction DHaa of the first through-hole 21aa is parallel to the opening surface 31s of the opening 31. That is, in the example shown in FIG. 17, the penetration direction DHaa of the first through-hole 21aa forms an angle of 0° with respect to the opening surface 31s of the opening 31.

[0266] Note that the penetration direction DHaa of the first through-hole 21aa may form an angle greater than 0° and less than 45° with respect to the opening surface 31s of the opening 31.

[0267] The penetration direction DHaa of the first through-hole 21aa may be parallel to the thickness direction of the first bus bar 20a (in FIG. 17, the third direction D3), or may not be parallel to the thickness direction of the first bus bar 20a (it may be inclined with respect to the thickness direction of the first bus bar 20a).

[0268] When the penetration direction DHaa of the first through-hole 21aa is parallel to the thickness direction of the first bus bar 20a, it is perpendicular to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a.

[0269] When the penetration direction DHaa of the first through-hole 21aa is not parallel to the thickness direction of the first bus bar 20a (when it is inclined with respect to the thickness direction of the first bus bar 20a), it is not perpendicular to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a (it is inclined with respect to the first main surface 20aa or the second main surface 20ab of the first bus bar 20a).

[0270] As shown in FIG. 17, the surface of the first bus bar 20a on which the first through-hole 21aa (similarly for the first through-hole 21ab described later) is provided is preferably perpendicular to the opening surface 31s of the opening 31.

[0271] In the example shown in FIG. 17, the first main surface 20aa and the second main surface 20ab of the first bus bar 20a in which the first through hole 21aa is provided are perpendicular to the opening surface 31s of the opening 31.

[0272] Note that the first main surface 20aa and the second main surface 20ab of the first bus bar 20a in which the first through hole 21aa is provided do not have to be perpendicular to the opening surface 31s of the opening 31.

[0273] As shown in FIGS. 15, 16, and 17, in the first bus bar 20a, a first through hole 21ab and a first protruding portion 25ab protruding from the periphery of the first through hole 21ab are further provided in a portion located between the capacitor element 10 and the opening 31.

[0274] As shown in FIG. 17, the protruding direction DPab of the first protruding portion 25ab forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0275] As shown in FIGS. 15 and 16, a part of the first through hole 21ab and the entire first protruding portion 25ab are embedded in the filling resin 40.

[0276] In the capacitor 3, since the protruding direction DPab of the first protruding portion 25ab forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, and a part of the first through hole 21ab and the entire first protruding portion 25ab are embedded in the filling resin 40, in the same manner as the above-described mechanism, even when the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0277] The features of the first through hole 21ab (for example, the penetrating direction DHab of the first through hole 21ab) are the same as the features of the first through hole 21aa including the above-described points.

[0278] The features of the first protruding portion 25ab (for example, the protruding direction DPab of the first protruding portion 25ab) are the same as the features of the first protruding portion 25aa including the above-described points.

[0279] As shown in FIGS. 15, 16, and 17, in the second bus bar 20b, a second through hole 21ba and a second protruding portion 25ba protruding from the periphery of the second through hole 21ba are provided in a portion located between the capacitor element 10 and the opening 31.

[0280] As shown in FIG. 17, the protruding direction DPba of the second protruding portion 25ba forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0281] As shown in FIGS. 15 and 16, a part of the second through hole 21ba and the entire second protruding portion 25ba are embedded in the filling resin 40.

[0282] In the capacitor 3, since the protruding direction DPba of the second protruding portion 25ba forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, and a part of the second through hole 21ba and the entire second protruding portion 25ba are embedded in the filling resin 40, in the same manner as the above-described mechanism, even when the temperature of the use environment changes, the occurrence of peeling between the second bus bar 20b and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0283] The features of the second through hole 21ba (for example, the penetrating direction DHba of the second through hole 21ba) are the same as the features of the first through hole 21aa including the above-described points.

[0284] The features of the second protruding portion 25ba (for example, the protruding direction DPba of the second protruding portion 25ba) are the same as the features of the first protruding portion 25aa including the above-described points.

[0285] As shown in FIG. 17, it is preferable that the surface of the second bus bar 20b where the second through hole 21ba (the same applies to the second through hole 21bb described later) is provided is perpendicular to the opening surface 31s of the opening 31.

[0286] In the example shown in FIG. 17, the first main surface 20ba and the second main surface 20bb of the second bus bar 20b in which the second through hole 21ba is provided are perpendicular to the opening surface 31s of the opening 31.

[0287] Note that the first main surface 20ba and the second main surface 20bb of the second bus bar 20b in which the second through hole 21ba is provided do not have to be perpendicular to the opening surface 31s of the opening 31.

[0288] As shown in FIGS. 15, 16, and 17, in the second bus bar 20b, a second through hole 21bb and a second protruding portion 25bb protruding from the periphery of the second through hole 21bb are further provided in a portion located between the capacitor element 10 and the opening 31.

[0289] As shown in FIG. 17, the protruding direction DPbb of the second protruding portion 25bb forms an angle of less than 45° with respect to the opening surface 31s of the opening 31.

[0290] As shown in FIGS. 15 and 16, a part of the second through hole 21bb and the entire second protruding portion 25bb are embedded in the filling resin 40.

[0291] In the capacitor 3, since the protruding direction DPbb of the second protruding portion 25bb forms an angle of less than 45° with respect to the opening surface 31s of the opening 31, and a part of the second through hole 21bb and the entire second protruding portion 25bb are embedded in the filling resin 40, in the same manner as the above-described mechanism, even when the temperature of the usage environment changes, the occurrence of peeling between the second bus bar 20b and the filling resin 40 and the occurrence of cracks in the filling resin 40 are suppressed.

[0292] The features of the second through hole 21bb (for example, the penetrating direction DHbb of the second through hole 21bb) are the same as the features of the first through hole 21aa including the above-described points.

[0293] The features of the second protruding portion 25bb (for example, the protruding direction DPbb of the second protruding portion 25bb) are the same as the features of the first protruding portion 25aa including the above-described points.

[0294] As shown in FIGS. 13, 14, 15, 16, and 17, in the region where the first bus bar 20a and the second bus bar 20b overlap, it is preferable that at least a part of the first through hole 21aa and at least a part of the second through hole 21ba overlap and communicate with each other. In this case, in the capacitor 3, since the first bus bar 20a and the second bus bar 20b are more firmly fixed by the filling resin 40 that has entered the first through hole 21aa and the second through hole 21ba, even if the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40, the occurrence of peeling between the second bus bar 20b and the filling resin 40, and the occurrence of cracks in the filling resin 40 are more suppressed.

[0295] In the example shown in FIGS. 13, 14, 15, 16, and 17, in the region where the first bus bar 20a and the second bus bar 20b overlap, the entire first through hole 21aa and the entire second through hole 21ba overlap and communicate with each other. However, the entire first through hole 21aa and a part of the second through hole 21ba may overlap and communicate with each other, or a part of the first through hole 21aa and the entire second through hole 21ba may overlap and communicate with each other, or a part of the first through hole 21aa and a part of the second through hole 21ba may overlap and communicate with each other.

[0296] As shown in FIGS. 13, 14, 15, 16, and 17, in the region where the first bus bar 20a and the second bus bar 20b overlap, it is preferable that at least a part of the first through hole 21ab and at least a part of the second through hole 21bb overlap and communicate with each other. In this case, in the capacitor 3, since the first bus bar 20a and the second bus bar 20b are more firmly fixed by the filling resin 40 that has entered the first through hole 21ab and the second through hole 21bb, even if the temperature of the use environment changes, the occurrence of peeling between the first bus bar 20a and the filling resin 40, the occurrence of peeling between the second bus bar 20b and the filling resin 40, and the occurrence of cracks in the filling resin 40 are more suppressed.

[0297] In the examples shown in FIGS. 13, 14, 15, 16, and 17, in the region where the first bus bar 20a and the second bus bar 20b overlap, the entire first through hole 21ab and the entire second through hole 21bb overlap and communicate with each other. However, the entire first through hole 21ab and a part of the second through hole 21bb may overlap and communicate with each other, or a part of the first through hole 21ab and the entire second through hole 21bb may overlap and communicate with each other, or a part of the first through hole 21ab and a part of the second through hole 21bb may overlap and communicate with each other.

[0298] In the second aspect of the capacitor of the present invention, the feature that "the protruding direction in which at least the tip side portion of the protruding portion extends forms an angle of less than 45° with respect to the opening surface of the opening, and at least a part of the through hole and the entire protruding portion are embedded in the filling resin" only needs to hold for at least one set of combinations of through holes and protruding portions. For example, in the capacitors 2 and 3, the above feature only needs to hold for at least one set of combinations of through holes and protruding portions selected from the group consisting of the combination of the first through hole 21aa and the first protruding portion 25aa, the combination of the first through hole 21ab and the first protruding portion 25ab, the combination of the second through hole 21ba and the second protruding portion 25ba, and the combination of the second through hole 21bb and the second protruding portion 25bb.

[0299] The second aspect of the capacitor of the present invention is not limited to the above embodiment, and various applications and modifications can be made within the scope of the present invention regarding the configuration of the capacitor, manufacturing conditions, etc.

[0300] For example, in the second aspect of the capacitor of the present invention, the number of capacitor elements housed inside one exterior case is not particularly limited. That is, in the second aspect of the capacitor of the present invention, one capacitor element may be housed inside one exterior case, or a plurality of capacitor elements (in the examples shown in FIGS. 8, 13, etc., two capacitor elements) may be housed.

[0301] In the second aspect of the capacitor of the present invention, the number of through holes and protrusions provided in a portion located between the capacitor element and the opening in one bus bar is not particularly limited. That is, in the second aspect of the capacitor of the present invention, one through hole and one protrusion may be provided in a portion located between the capacitor element and the opening in one bus bar, or a plurality of through holes and protrusions (in the examples shown in FIGS. 8 and 13, two each) may be provided.

[0302] The capacitor of the present invention is useful for power conversion devices such as inverters for motor drive mounted on electric vehicles, for example.

[0303] The following content is disclosed in this specification.

[0304] <1> A capacitor element having a body and an external electrode provided on the surface of the body, A bus bar electrically connected to the external electrode, A bottomed cylindrical outer case provided with an opening, and the capacitor element is housed inside such that the bus bar protrudes outward from the opening, A filling resin filled inside the outer case so as to embed the capacitor element, In the bus bar, a through hole is provided in a portion located between the capacitor element and the opening, The through direction in which the through hole extends forms an angle of less than 45° with respect to the opening surface of the opening, A capacitor, characterized in that the entire through hole is embedded in the filling resin.

[0305] <2> The capacitor according to <1>, wherein the through direction is parallel to the opening surface of the opening.

[0306] <3> The capacitor according to <1> or <2>, wherein the surface of the bus bar where the through hole is provided is perpendicular to the opening surface of the opening.

[0307] <4> The external electrode includes a first external electrode and a second external electrode, The bus bar includes a first bus bar electrically connected to the first external electrode and a second bus bar electrically connected to the second external electrode, The through hole includes a first through hole provided in the first bus bar and a second through hole provided in the second bus bar, In a region where the first bus bar and the second bus bar overlap, at least a part of the first through hole and at least a part of the second through hole overlap and communicate with each other. The capacitor according to any one of <1> to <3>.

[0308] <5> A capacitor element having a dielectric body and an external electrode provided on the surface of the dielectric body, A bus bar electrically connected to the external electrode, A bottomed cylindrical shape provided with an opening, and an exterior case in which the capacitor element is housed so that the bus bar protrudes outward from the opening, A filling resin filled inside the exterior case so as to embed the capacitor element, In the bus bar, a through hole and a protruding portion protruding from the periphery of the through hole are provided in a portion located between the capacitor element and the opening, The protruding direction in which at least the tip side portion of the protruding portion extends forms an angle of less than 45° with respect to the opening surface of the opening, At least a part of the through hole and the entire protruding portion are embedded in the filling resin. A capacitor characterized by this.

[0309] <6> The entire through hole and the entire protruding portion are embedded in the filling resin. The capacitor according to <5>.

[0310] <7> The capacitor according to <5>, wherein part of the through hole and the whole of the protruding portion are embedded in the filling resin.

[0311] <8> The capacitor according to any one of <5> to <7>, wherein the protruding direction is parallel to the opening surface of the opening.

[0312] <9> The capacitor according to any one of <5> to <8>, wherein the through direction in which the through hole extends forms an angle of less than 45° with respect to the opening surface of the opening.

[0313] <10> The capacitor according to <9>, wherein the through direction is parallel to the opening surface of the opening.

[0314] <11> The capacitor according to any one of <5> to <10>, wherein the surface of the bus bar on which the through hole is provided is perpendicular to the opening surface of the opening.

[0315] <12> The external electrode includes a first external electrode and a second external electrode. The bus bar includes a first bus bar electrically connected to the first external electrode and a second bus bar electrically connected to the second external electrode. The through hole includes a first through hole provided in the first bus bar and a second through hole provided in the second bus bar. The capacitor according to any one of <5> to <11>, wherein at least a part of the first through hole and at least a part of the second through hole overlap and communicate with each other in a region where the first bus bar and the second bus bar overlap.

[0316] <13> The capacitor according to any one of <1> to <12>, wherein the capacitor element is a film capacitor.

Description of reference numerals

[0317] 1, 2, and 3 capacitors 10 capacitor elements 11 body 11a first end face of the body 11b second end face of the body 11c side face of the body 12a first external electrode 12b second external electrode 13a first metallization film 13b second metallization film 14a first dielectric film 14aa first main face of the first dielectric film 14ab second main face of the first dielectric film 14b second dielectric film 14ba first main face of the second dielectric film 14bb second main face of the second dielectric film 15a first metal layer 15b second metal layer 20a first bus bar 20aa first main face of the first bus bar 20ab second main face of the first bus bar 20b second bus bar 20ba first main face of the second bus bar 20bb second main face of the second bus bar 21aa, 21ab first through hole 21aaa, 21aba first end of the first through hole 21aab, 21abb second end of the first through hole 21ba, 21bb second through hole 21baa, 21bba first end of the second through hole 21bab, 21bbb second end of the second through hole 25aa, 25ab first protrusion 25ba, 25bb second protrusion 30 outer case 31 opening 31s opening face of the opening 32 bottom 33 side wall portion 40 filling resin D1 First direction D2 Second direction D3 Third direction DHaa, DHab Penetration direction in which the first through-hole extends DHba, DHbb Penetration direction in which the second through-hole extends DPaa, DPab Protrusion direction in which at least the tip-side portion of the first protrusion extends DPba, DPbb Protrusion direction in which at least the tip-side portion of the second protrusion extends

Claims

1. A capacitor element having a body and an external electrode provided on the surface of the body, a bus bar electrically connected to the external electrode, a bottomed cylindrical case provided with an opening, the capacitor element being housed therein such that the bus bar protrudes outward from the opening, and a filling resin filled inside the outer case so as to embed the capacitor element, wherein a through hole is provided in a portion of the bus bar located between the capacitor element and the opening, the through direction in which the through hole extends forms an angle of less than 45° with respect to the opening surface of the opening, the entire through hole is embedded in the filling resin, the external electrode includes a first external electrode and a second external electrode, the bus bar includes a first bus bar electrically connected to the first external electrode and a second bus bar electrically connected to the second external electrode, the through hole includes a first through hole provided in the first bus bar and a second through hole provided in the second bus bar, in a region where the first bus bar and the second bus bar overlap, at least a part of the first through hole and at least a part of the second through hole overlap and communicate with each other. A capacitor characterized by this.

2. The capacitor according to claim 1, wherein the through direction is parallel to the opening surface of the opening.

3. The capacitor according to claim 1 or 2, wherein a surface of the bus bar on which the through hole is provided is perpendicular to the opening surface of the opening.

4. A capacitor element having a body and an external electrode provided on the surface of the body, a bus bar electrically connected to the external electrode, a bottomed cylindrical case provided with an opening, the capacitor element being housed therein such that the bus bar protrudes outward from the opening, and a filling resin filled inside the outer case so as to embed the capacitor element, wherein a through hole and a protruding portion protruding from the periphery of the through hole are provided in a portion of the bus bar located between the capacitor element and the opening, the protruding direction in which at least the tip-side portion of the protruding portion extends forms an angle of less than 45° with respect to the opening surface of the opening, and at least a part of the through hole and the entire protruding portion are embedded in the filling resin. A capacitor characterized by this.

5. The capacitor according to claim 4, wherein the whole of the through hole and the whole of the protruding portion are embedded in the filling resin.

6. The capacitor according to claim 4, wherein a part of the through hole and the whole of the protruding portion are embedded in the filling resin.

7. The capacitor according to any one of claims 4 to 6, wherein the protruding direction is parallel to the opening surface of the opening.

8. The capacitor according to any one of claims 4 to 6, wherein the through direction in which the through hole extends forms an angle of less than 45° with respect to the opening surface of the opening.

9. The capacitor according to claim 8, wherein the through direction is parallel to the opening surface of the opening.

10. The capacitor according to any one of claims 4 to 6, wherein the surface of the bus bar in which the through hole is provided is perpendicular to the opening surface of the opening.

11. The external electrode includes a first external electrode and a second external electrode, The bus bar includes a first bus bar electrically connected to the first external electrode and a second bus bar electrically connected to the second external electrode, The through hole includes a first through hole provided in the first bus bar and a second through hole provided in the second bus bar, The capacitor according to any one of claims 4 to 6, wherein at least a part of the first through hole and at least a part of the second through hole overlap and communicate with each other in a region where the first bus bar and the second bus bar overlap.

12. The capacitor according to claim 1 or 4, wherein the capacitor element is a film capacitor.

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