Capacitor

Abstract

A capacitor 1 comprises: a capacitor element 10 having an element body 11 and an external electrode 12a provided on an end surface of the element body 11; a lead-out terminal 20 electrically connected to the external electrode 12a; and an exterior case 30 in which the capacitor element 10 is housed. The exterior case 30 has a bottomed cylindrical shape having an opening part 31, and includes a bottom part 32 facing the opening part 31 in a first direction D1, and a side wall part 33 extending in the first direction D1 from the bottom part 32 toward the opening part 31. The lead-out terminal 20 is led out of the opening part 31 onto an outer surface 33a of the side wall part 33 while being bent, and extends from the opening part 31 side toward the bottom part 32 side in the first direction D1. The lead-out terminal 20 has a first surface 20a facing the outer surface 33a of the side wall part 33 in a second direction D2 perpendicular to the outer surface 33a of the side wall part 33, and a second surface 20b opposite the first surface 20a in the second direction D2. The outer surface 33a of the side wall part 33 is provided with a guard part 50 facing the second surface 20b of the lead-out terminal 20 in the second direction D2.

Description

capacitor

[0001] The present invention relates to a capacitor.

[0002] Patent document 1 discloses an electronic component having a plurality of chip components on which terminal electrodes are formed, a case having a plurality of accommodating recesses capable of accommodating the chip components, a plurality of conductive terminals fixed to the case and respectively connected to the terminal electrodes of the plurality of chip components, and a fuse that electrically connects the plurality of chip components to each other.

[0003] Japanese Patent Application Laid-Open No. 2021-190534

[0004] In a capacitor in which a capacitor element is housed inside an outer case, a lead terminal electrically connected to the capacitor element may be drawn out of the outer case and connected to a connection target such as an external device near the bottom of the outer case. In this case, the lead terminal is typically drawn out to the outer surface of the outer case through an opening provided in the top of the outer case and extended from the top to the bottom of the outer case. To achieve this, the lead terminal needs to be bent when drawn out from the opening of the outer case to the outer surface. However, in a capacitor in which the lead terminal is bent as described above, particularly when the lead terminal is a plate-shaped bus bar, the bent portion of the lead terminal elastically recovers to its original shape before bending, a phenomenon known as springback, which may cause the lead terminal to shift from its original position to the connection target.

[0005] In the electronic component described in Patent Document 1, as shown in Figures 1 and 5 of Patent Document 1, the conductive terminals connected to the terminal electrodes of the chip component are pulled out of the case and bent. Therefore, even in the electronic component described in Patent Document 1, springback may occur at the bent portions of the conductive terminals, which may cause the conductive terminals to shift in their connection positions relative to the connection object. As described above, the electronic component described in Patent Document 1 has room for improvement in terms of suppressing shifts in the connection positions of the conductive terminals relative to the connection object when springback occurs in the conductive terminals.

[0006] The present invention has been made to solve the above problems, and aims to provide a capacitor that can suppress deviation of the connection position of the lead terminal relative to the connection object, such as an external device, even if springback occurs in the lead terminal.

[0007] A capacitor according to the present invention comprises a capacitor element having a body and an external electrode provided on an end face of the body, a lead-out terminal electrically connected to the external electrode, and an outer case in which the capacitor element is housed, wherein the outer case is cylindrical with a bottom and has an opening, a bottom facing the opening in a first direction, and a side wall extending in the first direction from the bottom toward the opening, wherein the lead-out terminal is led out from the opening to an outer surface of the side wall while being bent, and extends from the opening side toward the bottom side in the first direction, wherein the lead-out terminal has a first surface facing the outer surface of the side wall in a second direction perpendicular to the outer surface of the side wall, and a second surface opposite the first surface in the second direction, and a guard portion is provided on the outer surface of the side wall, facing the second surface of the lead-out terminal in the second direction.

[0008] According to the present invention, it is possible to provide a capacitor that can suppress deviation of the connection position of the lead terminal relative to a connection target such as an external device even if springback occurs in the lead terminal.

[0009] FIG. 1 is a schematic perspective view showing an example of a capacitor according to embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of a cross section of the capacitor shown in FIG. 1 taken along line A1-A2. FIG. 3 is a schematic perspective view showing an example of a capacitor element shown in FIGS. 1 and 2. FIG. 4 is a schematic cross-sectional view showing an example of a cross section of the capacitor element shown in FIG. 3 taken along line B1-B2. FIG. 5 is a schematic perspective view showing another example of a capacitor according to embodiment 1 of the present invention. FIG. 6 is a schematic perspective view showing an example of a capacitor according to embodiment 2 of the present invention. FIG. 7 is a schematic perspective view showing an example of a capacitor according to embodiment 3 of the present invention. FIG. 8 is a schematic perspective view showing another example of a capacitor according to embodiment 3 of the present invention. FIG. 9 is a schematic perspective view showing an example of a capacitor according to embodiment 4 of the present invention. FIG. 10 is a schematic perspective view showing an example of a capacitor according to embodiment 5 of the present invention.

[0010] The capacitor of the present invention will be described below. Note that the present invention is not limited to the following configurations and may be modified as appropriate within the scope of the present invention. In addition, a combination of multiple individual preferred configurations described below also constitutes the present invention.

[0011] The following embodiments are merely examples, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. From embodiment 2 onwards, descriptions of matters common to embodiment 1 will be omitted, and differences will be mainly described. In particular, similar effects resulting from similar configurations will not be mentioned one after the other for each embodiment.

[0012] In the following description, when there is no need to particularly distinguish between the embodiments, they will simply be referred to as "the capacitor of the present invention."

[0013] Although a film capacitor will be described below as an example of the capacitor of the present invention, the capacitor of the present invention can also be applied to capacitors other than film capacitors.

[0014] The drawings shown below are schematic diagrams, and the dimensions, aspect ratio, scale, etc. may differ from those of the actual product.

[0015] In this specification, unless otherwise specified, terms indicating the relationship between elements (e.g., "parallel," "perpendicular," etc.) and terms indicating the shape of elements not only mean the literal strict form, but also mean a range that is substantially equivalent, for example, a range that includes a difference of about a few percent.

[0016] A capacitor according to the present invention comprises a capacitor element having a body and an external electrode provided on an end face of the body, a lead-out terminal electrically connected to the external electrode, and an outer case in which the capacitor element is housed, wherein the outer case is cylindrical with a bottom and has an opening, a bottom facing the opening in a first direction, and a side wall extending in the first direction from the bottom toward the opening, wherein the lead-out terminal is led out from the opening to an outer surface of the side wall while being bent, and extends from the opening side toward the bottom side in the first direction, wherein the lead-out terminal has a first surface facing the outer surface of the side wall in a second direction perpendicular to the outer surface of the side wall, and a second surface opposite the first surface in the second direction, and a guard portion is provided on the outer surface of the side wall, facing the second surface of the lead-out terminal in the second direction.

[0017] [First Embodiment] In a capacitor according to a first embodiment of the present invention, the lead terminals are locked to the guard portion.

[0018] In the capacitor of embodiment 1 of the present invention, the guard portion has a hole on the opening side in the first direction, and the lead-out terminal has a main portion extending in the first direction and a hooked branch portion that branches off from the main portion in a hook-like shape so that the tip faces the bottom side in the first direction, and the hooked branch portion is inserted into the hole.

[0019] Fig. 1 is a schematic perspective view showing an example of a capacitor according to embodiment 1 of the present invention. Fig. 2 is a schematic cross-sectional view showing an example of a cross section of the capacitor shown in Fig. 1 taken along line A1-A2.

[0020] The capacitor 1 shown in FIGS. 1 and 2 includes a capacitor element 10 , lead terminals 20 , and an outer case 30 .

[0021] In FIG. 1 and other figures, the first direction D1, the second direction D2, and the third direction D3 are perpendicular to one another.

[0022] Fig. 3 is a schematic perspective view showing an example of the capacitor element shown in Fig. 1 and Fig. 2. Fig. 4 is a schematic cross-sectional view showing an example of a cross section of the capacitor element shown in Fig. 3 taken along line B1-B2.

[0023] The capacitor element 10 shown in FIGS. 3 and 4 has an element body 11, a first external electrode 12a, and a second external electrode 12b.

[0024] Body 11 is a wound body in which first metallized film 13 a and second metallized film 13 b are wound in a stacked state in third direction D3. In other words, capacitor 1, specifically capacitor element 10, is a wound-type film capacitor in which metallized films are wound in a stacked state.

[0025] Note that capacitor 1, specifically capacitor element 10, may be a laminated film capacitor (for example, rectangular parallelepiped) in which metallized films are laminated.

[0026] From the viewpoint of reducing the height of capacitor element 10, element body 11 preferably has a flat cross-sectional shape when viewed in a cross section perpendicular to the winding axis direction (second direction D2 in FIGS. 3 and 4 ) of element body 11. Specifically, element body 11 is preferably pressed into a flattened shape such as an ellipse or oval, and has a smaller thickness than when the cross-sectional shape of element body 11 is a perfect circle.

[0027] Whether or not the element body has been pressed to have a flat cross-sectional shape can be confirmed, for example, by checking whether or not there are press marks on the element body.

[0028] Capacitor element 10 may have a cylindrical winding shaft that is disposed on the central axis of first metallized film 13 a and second metallized film 13 b in a wound state and serves as the winding shaft when winding first metallized film 13 a and second metallized film 13 b.

[0029] First metallized film 13a includes first dielectric film 14a and first metal layer 15a.

[0030] The first dielectric film 14a has a first main surface 14aa and a second main surface 14ab facing each other in the third direction D3.

[0031] 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 second direction D2 but not reach the other side edge of the first dielectric film 14a.

[0032] Second metallized film 13b includes second dielectric film 14b and second metal layer 15b.

[0033] The second dielectric film 14b has a first main surface 14ba and a second main surface 14bb that face each other in the third direction D3.

[0034] 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 in the second direction D2 but to reach the other side edge of the second dielectric film 14b.

[0035] In the element body 11, adjacent first metallized films 13a and second metallized films 13b are offset in the second direction D2 so that the end of the first metal layer 15a that reaches the side edge of the first dielectric film 14a is exposed at one end surface of the element body 11, and the end of the second metal layer 15b that reaches the side edge of the second dielectric film 14b is exposed at the other end surface of the element body 11. That is, in adjacent first metallized films 13a and second metallized films 13b, the first metallized film 13a protrudes toward the first external electrode 12a relative to the second metallized film 13b. Also, in adjacent first metallized films 13a and second metallized films 13b, the second metallized film 13b protrudes toward the second external electrode 12b relative to the first metallized film 13a. In this state, the first metal layer 15a is connected to the first external electrode 12a but not to the second external electrode 12b. The second metal layer 15b is connected to the second external electrode 12b and is not connected to the first external electrode 12a.

[0036] In the element body 11, the adjacent first metallized films 13a and second metallized films 13b are offset in the second direction D2 as described above, so that, among the adjacent first dielectric films 14a and second dielectric films 14b, the first dielectric film 14a having the first metal layer 15a on its first main surface 14aa protrudes toward the first external electrode 12a relative to the second dielectric film 14b having the first metal layer 15a not provided on its main surface. Furthermore, among the adjacent first dielectric films 14a and second dielectric films 14b, the second dielectric film 14b having the second metal layer 15b on its first main surface 14ba protrudes toward the second external electrode 12b relative to the first dielectric film 14a having the second metal layer 15b not provided on its main surface.

[0037] Since element body 11 is formed by winding first metallized film 13a and second metallized film 13b in a stacked state in third direction D3, it can be said that element body 11 includes first dielectric film 14a, first metal layer 15a, second dielectric film 14b, and second metal layer 15b in this order in third direction D3. It can also be said that element body 11 is a wound body formed by winding first dielectric film 14a, first metal layer 15a, second dielectric film 14b, and second metal layer 15b in this order in third direction D3.

[0038] In element body 11, first main surface 14aa of first dielectric film 14a and second main surface 14bb of second dielectric film 14b face each other in third direction D3, and second main surface 14ab of first dielectric film 14a and first main surface 14ba of second dielectric film 14b face each other in third direction D3. Thus, in element body 11, first metallized film 13a and second metallized film 13b are wound in a stacked state in third direction D3. In other words, in element body 11, first metallized film 13a is on the inside of second metallized film 13b, specifically, first metal layer 15a is on the inside of first dielectric film 14a, and second metal layer 15b is on the inside of second dielectric film 14b. 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 sandwiched therebetween.

[0039] 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 formed by dividing a portion of the first metal layer 15a that faces the second metal layer 15b into multiple portions with an electrode portion that does not face the second metal layer 15b. Examples of electrode patterns of the first metal layer 15a provided with a fuse portion include the electrode patterns disclosed in Japanese Patent Laid-Open Nos. 2004-363431 and 5-251266.

[0040] The second metal layer 15b may also be provided with a fuse portion, similar to the first metal layer 15a.

[0041] The first dielectric film 14a may contain a curable resin as a main component.

[0042] In this specification, the term "major component" means the component with the highest weight percentage, preferably a component with a weight percentage greater than 50% by weight.

[0043] The curable resin may be a thermosetting resin or a photocurable resin.

[0044] In this specification, thermosetting resin means a resin that can be cured by heat, but the curing method is not limited thereto. Therefore, thermosetting resins also include resins that can be cured by methods other than heat (e.g., light, electron beam, etc.) as long as they are resins that can be cured by heat. Furthermore, depending on the material, a reaction may be initiated due to the reactivity of the material itself, and resins that proceed to cure without necessarily being subjected to external heat or the like are also considered thermosetting resins. The same applies to photocurable resins; as long as they are resins that can be cured by light, they also include resins that can be cured by methods other than light (e.g., heat, etc.).

[0045] The curable resin is preferably 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 is a cured product having a urethane bond obtained by reacting the hydroxyl group of the first organic material with the isocyanate group of the second organic material.

[0046] The presence of urethane bonds in the dielectric film can be confirmed by analysis with a Fourier transform infrared spectrophotometer (FT-IR).

[0047] When the curable resin is obtained by the above-described reaction, uncured portions 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 either a hydroxyl group or an isocyanate group, or may contain both a hydroxyl group and an isocyanate group.

[0048] The presence of hydroxyl groups and / or isocyanate groups in the dielectric film can be confirmed by FT-IR analysis.

[0049] Examples of the first organic material include phenoxy resin, polyvinyl acetoacetal resin, and polyvinyl butyral resin.

[0050] As the first organic material, a plurality of types of organic materials may be used in combination.

[0051] 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 modified product of these polyisocyanates may be used.

[0052] As the second organic material, a plurality of types of organic materials may be used in combination.

[0053] The first dielectric film 14a may contain a thermoplastic resin as a main component.

[0054] Examples of the thermoplastic resin include polypropylene resin, polyethersulfone resin, polyetherimide resin, and polyarylate resin.

[0055] The first dielectric film 14a may contain additives to impart various functions.

[0056] The additives include, for example, a leveling agent for imparting smoothness.

[0057] 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.

[0058] Like the first dielectric film 14a, the second dielectric film 14b may contain a thermosetting resin as a main component, a photocurable resin as a main component, or a thermoplastic resin as a main component, and like the first dielectric film 14a, the second dielectric film 14b may also contain an additive.

[0059] The first dielectric film 14a and the second dielectric film 14b may have different compositions, but preferably have the same composition.

[0060] The thickness of the first dielectric film 14a and the second dielectric film 14b is preferably 1 μm or more and 10 μm or less, and more preferably 3 μm or more and 5 μm or less.

[0061] 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.

[0062] The thickness of the dielectric film is measured using an optical film thickness gauge.

[0063] The first dielectric film 14a and the second dielectric film 14b are each preferably produced by forming a resin solution containing the resin material as described above into a film and then curing it by heat treatment.

[0064] Examples of materials that can be used to form the first metal layer 15a and the second metal layer 15b include metals such as aluminum, zinc, titanium, magnesium, tin, and nickel.

[0065] The first metal layer 15a and the second metal layer 15b may have different compositions, but preferably have the same composition.

[0066] The thickness of the first metal layer 15a and the second metal layer 15b is preferably 5 nm or more and 40 nm or less.

[0067] The thickness of the first metal layer 15a and the second metal layer 15b may be different from each other, but it is preferable that they are the same.

[0068] The thickness of the metal layer is measured by observing a cross section of the metallized film along the third direction using a transmission electron microscope (TEM).

[0069] The first metal layer 15a and the second metal layer 15b are preferably formed by depositing the metals described above on the major surfaces of the first dielectric film 14a and the second dielectric film 14b, respectively.

[0070] Although the above describes an embodiment in which element body 11 includes two metallized films, element body 11 may also include a single metallized film. For example, element body 11 may include a metallized film having first dielectric film 14a with first metal layer 15a provided on first main surface 14aa and second metal layer 15b provided on second main surface 14ab, and a second dielectric film 14b with no metal layer. Alternatively, element body 11 may include a metallized film having second dielectric film 14b with first metal layer 15a provided on second main surface 14bb and second metal layer 15b provided on first main surface 14ba, and a first dielectric film 14a with no metal layer.

[0071] The first external electrode 12a is provided on one end surface of the element body 11. Specifically, the first external electrode 12a is connected to the first metal layer 15a by contacting the end of the first metal layer 15a exposed on one end surface of the element body 11. On the other hand, the first external electrode 12a is not connected to the second metal layer 15b.

[0072] The second external electrode 12b is provided on the other end surface of the element body 11. Specifically, the second external electrode 12b is connected to the second metal layer 15b by contacting the end of the second metal layer 15b exposed on the other end surface of the element body 11. On the other hand, the second external electrode 12b is not connected to the first metal layer 15a.

[0073] Examples of materials that can be used to form the first external electrode 12a and the second external electrode 12b include metals such as zinc, aluminum, tin, and zinc-aluminum alloys.

[0074] The first external electrode 12a and the second external electrode 12b may have different compositions, but preferably have the same composition.

[0075] The first external electrode 12a and the second external electrode 12b are preferably formed by spraying the above-mentioned metal onto one end surface and the other end surface of the element body 11, respectively.

[0076] As shown in FIG. 2, the lead terminal 20 is electrically connected to one of the first external electrode 12a and the second external electrode 12b, here, the first external electrode 12a.

[0077] The lead terminal 20 may be welded to the first external electrode 12a, or may be connected via a joining member such as solder.

[0078] Examples of materials that can be used to form the lead terminal 20 include metals such as copper, oxygen-free copper, aluminum, and alloys containing at least one of these. Among these, copper or oxygen-free copper is preferred as the material for the lead terminal 20. When the material for the lead terminal 20 is a copper-based material, examples that can be used include oxygen-free copper (copper: 99.96% by weight or more), tough pitch copper (copper: 99.90% by weight or more), and phosphorus-deoxidized copper (copper: 99.90% by weight or more, phosphorus: 0.015% by weight or more, 0.040% by weight or less).

[0079] The shape of the lead-out terminal 20 may be, for example, a plate-like shape or a linear (rod-like) shape. When the lead-out terminal 20 is plate-like, the lead-out terminal 20 is also called a bus bar.

[0080] As shown in FIGS. 1 and 2, the capacitor element 10 is housed inside the exterior case 30.

[0081] As shown in FIG. 2, capacitor element 10 is preferably housed in the center of outer case 30 while being spaced apart from the inner surface of outer case 30 .

[0082] The outer case 30 is a cylindrical shape with a bottom and an opening 31. Specifically, the outer case 30 is a cylindrical shape with a bottom and an opening 31 at one end in the first direction D1.

[0083] The exterior case 30 has a bottom 32 facing the opening 31 in the first direction D1, and a side wall 33 extending from the bottom 32 toward the opening 31 in the first direction D1.

[0084] The exterior case 30 may be, for example, a resin case or a metal case.

[0085] When the exterior case 30 is a resin case, examples of the resin that constitutes the resin case include liquid crystal polymer (LCP), polyphenylene sulfide resin, polybutylene terephthalate resin, etc. Among these, it is preferable that the resin case contains a liquid crystal polymer.

[0086] The liquid crystal polymer contained in the resin case may be, for example, a liquid crystal polymer having p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid groups in its skeleton. Liquid crystal polymers formed as polycondensates using various components other than p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid groups, such as phenol, phthalic acid, and ethylene terephthalate, may also be used. Liquid crystal polymers are also classified into types I, II, and III, but the material refers to the same material as the liquid crystal polymer formed from the above-mentioned components.

[0087] The resin case preferably further contains an inorganic filler in addition to the liquid crystal polymer.

[0088] The inorganic filler contained in the resin case can be a material having a higher strength than the liquid crystal polymer. 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.

[0089] The shape of the inorganic filler is not particularly limited, and examples thereof include a shape having a longitudinal direction, such as a fibrous or plate-like shape. As the inorganic filler having such a shape, multiple types of inorganic materials may be used in combination. It is preferable that the resin case contains at least one of a fibrous inorganic material and a plate-like inorganic material as the inorganic filler.

[0090] In this specification, a filler being fibrous means that 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 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 longest two points on the periphery of the cross section. If the cross-sectional diameter varies in the longitudinal direction, measurement is performed at the point where the cross-sectional diameter is largest.

[0091] In this specification, a filler being plate-shaped means that the relationship between the cross-sectional diameter of the face having the largest projected area and the maximum height in the direction perpendicular to this cross section is cross-sectional diameter / maximum height ≧3.

[0092] It is preferable that at least a portion of the inorganic filler has a portion in the side wall portion 33 that is oriented in a direction from the bottom portion 32 toward the opening portion 31 and a portion that is oriented in the outer circumferential direction of the side wall portion 33, and is dispersed inside the outer case 30.

[0093] The size of the inorganic filler is preferably 5 μm or more in diameter and 50 μm or more in length.

[0094] It is preferable that the inorganic filler be dispersed throughout the exterior case 30 without agglomerating.

[0095] Examples of inorganic fillers include inorganic materials such as fibrous glass filler, plate-like talc or mica, etc. Among these, it is preferable that the inorganic filler contains fibrous glass filler as a main component.

[0096] 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 an inorganic filler as described above.

[0097] The resin case is manufactured by a method such as injection molding.

[0098] When the exterior case 30 is a metal case, examples of the metal constituting the metal case include simple metals such as aluminum, magnesium, iron, stainless steel, and copper, and alloys containing at least one of these simple metals. Of these, it is preferable that the metal case contains aluminum or an aluminum alloy.

[0099] The metal case is manufactured by a method such as impact molding.

[0100] 1 and 2 , the capacitor 1 may further include a filling resin 40 filled inside the exterior case 30 so as to embed the capacitor element 10. When the filling resin 40 is filled in this manner, the capacitor element 10 is held inside the exterior case 30.

[0101] When capacitor element 10 is housed inside outer case 30 so as to be spaced apart from the inner surface of outer case 30, filling resin 40 is filled between capacitor element 10 and outer case 30, more specifically, between the outer surface of capacitor element 10 and the inner surface of outer case 30. Furthermore, inside outer case 30, filling resin 40 is filled not only between capacitor element 10 and outer case 30, but also in the region from opening 31 of outer case 30 to capacitor element 10.

[0102] From the viewpoint of suppressing the penetration of moisture into capacitor element 10, it is preferable to appropriately select a resin with low moisture permeability as filling resin 40, such as epoxy resin, silicone resin, urethane resin, etc. Examples of the curing agent for epoxy resin include an amine curing agent, an imidazole curing agent, etc.

[0103] The above-mentioned resin alone may be used as the filling resin 40, but in order to improve strength, a resin to which a reinforcing agent has been added may also be used. Examples of the reinforcing agent include silica and alumina.

[0104] From the viewpoint of suppressing the penetration of moisture into capacitor element 10, it is preferable that the thickness of filling resin 40 at opening 31 of outer case 30 is large. The thickness of filling resin 40 at opening 31 of outer case 30 is preferably sufficiently large within the allowable range for the overall volume (physical size) of capacitor 1, and specifically, is preferably 2 mm or more, and more preferably 4 mm or more. In particular, it is preferable that, inside outer case 30, capacitor element 10 is disposed closer to bottom 32 of outer case 30 than to opening 31, so that the thickness of filling resin 40 relative to capacitor element 10 is greater on the opening 31 side of outer case 30 than on the bottom 32 side.

[0105] The thickness of the filled resin 40 is measured, for example, using a soft X-ray device if it is in a non-destructive state, and using a length measuring device such as a caliper if it is in a destructive state.

[0106] The relationship between the height of the outer case 30 and the height of the filling resin 40 in the first direction D1 is such that the thickness of the filling resin 40 at the opening 31 of the outer case 30 is as large as possible, and it may be up to a position inside the outer case 30, or it may be just about to the top, or it may overflow slightly due to surface tension.

[0107] 1 and 2, the lead-out terminal 20 is bent as it is drawn out from the opening 31 to the outer surface 33a of the side wall portion 33. In the example shown in Fig. 1 and 2, the lead-out terminal 20 has bent portions 21a and 21b bent at an angle of approximately 90° in the middle of being drawn out from the opening 31 to the outer surface 33a of the side wall portion 33.

[0108] The lead-out terminal 20 is drawn out from the opening 31 to the outer surface 33 a of the side wall 33, and then extends in the first direction D1 from the opening 31 side toward the bottom 32 side. In other words, the lead-out terminal 20 extends from the opening 31 side toward the bottom 32 side along the outer surface 33 a of the side wall 33.

[0109] The pull-out terminal 20 may extend parallel to the outer surface 33a of the side wall portion 33, as long as it can be said to be along the outer surface 33a of the side wall portion 33, or it does not have to extend parallel to the outer surface 33a of the side wall portion 33.

[0110] The lead terminal 20 has a first surface 20a facing the outer surface 33a of the side wall portion 33 in the second direction D2 perpendicular to the outer surface 33a of the side wall portion 33, and a second surface 20b facing the first surface 20a in the second direction D2. In other words, in the second direction D2, the first surface 20a of the lead terminal 20 faces the outer surface 33a of the side wall portion 33, but the second surface 20b of the lead terminal 20 does not face the outer surface 33a of the side wall portion 33.

[0111] The first surface 20a of the lead-out terminal 20 may be in contact with the outer surface 33a of the side wall portion 33 in the second direction D2, or may be spaced apart from the outer surface 33a of the side wall portion 33 in the second direction D2.

[0112] The lead-out terminal 20 extends from the opening 31 side toward the bottom 32 side in the first direction D1, and is then connected to the connection object 100 such as an external device. As a result, the capacitor element 10 is electrically connected to the connection object 100 via the lead-out terminal 20.

[0113] The lead-out terminal 20 is preferably welded to the connection object 100 .

[0114] When the lead-out terminal 20 is welded to the connection object 100, the lead-out terminal 20 is more likely to be firmly fixed to the connection object 100 than when the lead-out terminal 20 is fixed to the connection object 100 by screw fastening, solder joining, etc.

[0115] When lead-out terminal 20 is welded to connection object 100, the connection resistance between lead-out terminal 20 and connection object 100 is likely to decrease. This makes it easier to improve the conductivity between capacitor element 10 and connection object 100.

[0116] Welding methods such as laser welding and resistance welding are used to weld the lead terminal 20 to the connection object 100. In particular, laser welding has the advantage that welding can be completed in a short time by localized heating compared to other welding methods, and therefore welding distortion can be reduced.

[0117] As shown in FIG. 1, a guard portion 50 is provided on the outer surface 33 a of the side wall portion 33 .

[0118] The guard portion 50 faces the second surface 20b of the lead-out terminal 20 in the second direction D2.

[0119] 1, the guard portion 50 surrounds at least a portion of the second surface 20b of the pull-out terminal 20. The guard portion 50 is provided so as to overlap the pull-out terminal 20 when viewed from the second direction D2.

[0120] The second surface 20b of the lead-out terminal 20 may be in contact with the guard portion 50 in the second direction D2, or may be spaced apart from the guard portion 50 in the second direction D2.

[0121] In the capacitor 1, particularly when the lead terminal 20 is a plate-shaped bus bar, springback occurs at the bent portion of the lead terminal 20 (particularly the bent portion 21b in the example shown in FIGS. 1 and 2), causing the portion of the lead terminal 20 extending from the opening 31 side toward the bottom 32 side in the first direction D1 (the portion along the outer surface 33a of the side wall portion 33) to move in a direction away from the outer case 30, or in the second direction D2 in the example shown in FIGS. 1 and 2. In particular, the longer the portion of the lead terminal 20 extending from the opening 31 side toward the bottom 32 side in the first direction D1, the more likely the lead terminal 20 will move in a direction away from the outer case 30 due to springback.

[0122] In contrast, in the capacitor 1, the guard portion 50 is provided for the lead terminal 20 as described above, which suppresses movement of the lead terminal 20 away from the exterior case 30 due to springback. As a result, even if springback occurs in the lead terminal 20, the connection position of the lead terminal 20 with respect to the connection object 100, such as an external device, is less likely to shift. In particular, when the lead terminal 20 is laser-welded to the connection object 100, high positional accuracy of the lead terminal 20 with respect to the connection object 100 is required, and therefore, a capacitor 1 in which the connection position of the lead terminal 20 with respect to the connection object 100 is less likely to shift even if springback occurs in the lead terminal 20 is useful.

[0123] Specific embodiments of the guard portion 50 in the capacitor 1 will be described below.

[0124] As shown in FIG. 1, the guard portion 50 may protrude from the side wall portion 33 in the second direction D2.

[0125] The guard portion 50 does not have to protrude in the second direction D2 from the side wall portion 33. For example, a recess may be provided in the side wall portion 33, and the guard portion 50 may be provided in the recess.

[0126] 1, the guard portion 50 may be integrated with the side wall portion 33. In other words, the guard portion 50 constitutes a part of the outer case 30. In the example shown in FIG. 1, the guard portion 50 is a protrusion formed by a part of the outer case 30 protruding in the second direction D2.

[0127] In this specification, two elements being integrated means that there is no interface between the elements, for example, it means that the boundary between the elements cannot be discerned.

[0128] The guard portion 50 does not have to be integrated with the side wall portion 33. For example, the guard portion 50 may be provided on the outer surface 33a of the side wall portion 33 as a separate member independent of the exterior case 30. In this case, the guard portion 50 may be adhered to the outer surface 33a of the side wall portion 33 with an adhesive.

[0129] 1, the lead-out terminal 20 is locked to the guard portion 50. Specifically, this is as follows.

[0130] The guard portion 50 has a hole 51 formed on the opening 31 side in the first direction D1. In the example shown in Fig. 1, the guard portion 50 includes a guard portion 50a and a guard portion 50b provided at positions spaced apart from each other in the third direction D3. In the example shown in Fig. 1, the guard portion 50a has a hole 51a formed on the opening 31 side in the first direction D1, and the guard portion 50b has a hole 51b formed on the opening 31 side in the first direction D1.

[0131] The lead-out terminal 20 has a main portion 22 extending in the first direction D1 and a hooked branch portion 23 branching off from the main portion 22 in a hook-like shape so that the tip thereof faces the bottom portion 32 in the first direction D1. In the example shown in Fig. 1 , the hooked branch portion 23 includes a hooked branch portion 23a branching off from the main portion 22 on one side in the third direction D3 and a hooked branch portion 23b branching off from the main portion 22 on the other side in the third direction D3.

[0132] The hooked branch portion 23 is inserted into the hole 51. In the example shown in Fig. 1, the hooked branch portion 23a is inserted into the hole 51a, and the hooked branch portion 23b is inserted into the hole 51b. In this manner, the lead-out terminal 20 is locked to the guard portion 50, that is, the guard portions 50a and 50b in the example shown in Fig. 1.

[0133] In the example shown in FIG. 1, two guard portions and two hooked branch portions inserted into holes in the guard portions are provided, but one guard portion and one hooked branch portion may be provided, or three or more of each may be provided.

[0134] 1 , the distance between the bottom 32 and the guard portion 50 in the first direction D1 is preferably equal to or less than half the distance between the bottom 32 and the opening 31. In the example shown in FIG. 1 , the distance between the bottom 32 and the guard portion 50a and the distance between the bottom 32 and the guard portion 50b in the first direction D1 are both equal to or less than half the distance between the bottom 32 and the opening 31.

[0135] As described above, the longer the portion of the drawer terminal 20 that extends from the opening 31 side toward the bottom 32 side in the first direction D1, the more likely the drawer terminal 20 will move away from the outer case 30 due to springback. On the other hand, if the guard portion 50 is provided on the bottom 32 side with respect to the outer surface 33a of the side wall portion 33 so that the distance between the bottom 32 and the guard portion 50 in the first direction D1 is equal to or less than half the distance between the bottom 32 and the opening 31, movement of the drawer terminal 20 in the direction away from the outer case 30 due to springback is sufficiently suppressed even if the portion of the drawer terminal 20 that extends from the opening 31 side toward the bottom 32 side in the first direction D1 is long.

[0136] In the example shown in Figure 1, the bottom 32 side of the guard portion 50 in the first direction D1, specifically, the bottom 32 side of the guard portion 50a and the guard portion 50b in the first direction D1, is shown to be closed and not open, but the bottom 32 side of the guard portion 50a and the guard portion 50b in the first direction D1 may be open.

[0137] FIG. 5 is a schematic perspective view showing another example of the capacitor according to the first embodiment of the present invention.

[0138] 5, the guard portions 50a and 50b are open on the sides of the bottom 32 in the first direction D1. That is, the hole 51a penetrates the guard portion 50a, and the hole 51b penetrates the guard portion 50b in the first direction D1.

[0139] Since the guard portion 50a is open on the bottom 32 side, as shown in FIG. 5, the hook-shaped branch portion 23a inserted into the hole 51a may protrude from the guard portion 50a toward the bottom 32 side.

[0140] Even if the guard portion 50a is open on the bottom 32 side, the hook-shaped branch portion 23a inserted into the hole 51a does not have to protrude from the guard portion 50a toward the bottom 32 side.

[0141] Since the guard portion 50b is open on the bottom 32 side, as shown in FIG. 5, the hook-shaped branch portion 23b inserted into the hole 51b may protrude from the guard portion 50b toward the bottom 32 side.

[0142] Even if the guard portion 50b is open on the bottom 32 side, the hook-shaped branch portion 23b inserted into the hole 51b does not have to protrude from the guard portion 50b toward the bottom 32 side.

[0143] In this specification, the adhesive portion that adheres the lead terminal to the outer surface of the side wall portion so as to surround at least a part of the second surface of the lead terminal is not included in the guard portion.

[0144] [Embodiment 2] In a capacitor according to embodiment 2 of the present invention, the guard portion has a hole penetrating the guard portion in a first direction, and the lead-out terminal has a main portion extending in the first direction but does not have a branch portion branching from the main portion, and the main portion is inserted into the hole.

[0145] The capacitor of the second embodiment of the present invention is similar to the capacitor of the first embodiment of the present invention except for the above points.

[0146] FIG. 6 is a schematic perspective view showing an example of a capacitor according to the second embodiment of the present invention.

[0147] In the capacitor 2 shown in FIG. 6, the guard portion 50 is provided with a hole 51 that penetrates the guard portion 50 in the first direction D1.

[0148] The lead-out terminal 20 has a main portion 22 extending in the first direction D1. On the other hand, the lead-out terminal 20 does not have a branch portion branching from the main portion 22.

[0149] The main part 22 is inserted into the hole 51. Since the hole 51 penetrates the guard part 50 in the first direction D1, the main part 22 inserted into the hole 51 penetrates the guard part 50 in the first direction D1.

[0150] [Embodiment 3] In a capacitor according to embodiment 3 of the present invention, the guard portion is provided with a groove extending in a third direction perpendicular to the first and second directions, and the lead-out terminal has a main portion extending in the first direction and a linear branch portion branching off linearly from the main portion so that the tip faces the guard portion in the third direction, and the linear branch portion is fitted into the groove.

[0151] The capacitor of the third embodiment of the present invention is similar to the capacitor of the first embodiment of the present invention except for the above points.

[0152] FIG. 7 is a perspective schematic view showing an example of a capacitor according to a third embodiment of the present invention.

[0153] In the capacitor 3 shown in Fig. 7, the guard portion 50 is provided with a groove 52 extending in the third direction D3. In the example shown in Fig. 7, the guard portion 50 includes a guard portion 50c and a guard portion 50d that are provided at positions spaced apart from each other in the third direction D3. In the example shown in Fig. 7, the guard portion 50c is provided with a groove 52a extending in the third direction D3, and the guard portion 50d is provided with a groove 52b extending in the third direction D3.

[0154] The lead-out terminal 20 has a main portion 22 extending in the first direction D1 and a linear branch portion 24 branching off linearly from the main portion 22 so that the tip thereof faces the guard portion 50 in the third direction D3. In the example shown in Fig. 7 , the linear branch portion 24 includes a linear branch portion 24a branching off to one side of the main portion 22 in the third direction D3 and a linear branch portion 24b branching off to the other side of the third direction D3.

[0155] The linear branch portion 24 is fitted into the groove 52. In the example shown in Fig. 7, the linear branch portion 24a is fitted into the groove 52a, and the linear branch portion 24b is fitted into the groove 52b. In this manner, the lead-out terminal 20 is locked by the guard portion 50, or in the example shown in Fig. 7, the guard portions 50c and 50d.

[0156] In the example shown in Figure 7, the linear branch portion 24a fitted into the groove 52a may protrude from the guard portion 50c to the side opposite the lead-out terminal 20 (the side opposite the guard portion 50d), or may not protrude from the guard portion 50c to the side opposite the lead-out terminal 20.

[0157] In the example shown in Figure 7, the linear branch portion 24b fitted into the groove 52b may protrude from the guard portion 50d to the side opposite the lead-out terminal 20 (the side opposite the guard portion 50c), or may not protrude from the guard portion 50d to the side opposite the lead-out terminal 20.

[0158] In the example shown in FIG. 7, two guard portions and two linear branch portions fitted into the grooves of the guard portions are provided, but one guard portion and one linear branch portion may be provided, or three or more guard portions and one linear branch portion may be provided.

[0159] In the example shown in Figure 7, the bottom 32 side of the guard portion 50 in the first direction D1, specifically, the bottom 32 side of the guard portion 50c and the guard portion 50d in the first direction D1, is shown to be closed and not open, but the bottom 32 side of the guard portion 50c and the guard portion 50d in the first direction D1 may be open.

[0160] FIG. 8 is a schematic perspective view showing another example of the capacitor according to the third embodiment of the present invention.

[0161] 8, the guard portions 50c and 50d are open on the side of the bottom 32 in the first direction D1. Instead, the guard portions 50c and 50d are connected to the side wall 33 at their ends opposite the lead-out terminal 20 in the third direction D3 (in the example shown in FIG. 8, they are integrated with the side wall 33).

[0162] Since the guard portion 50c is open on the bottom 32 side, the linear branch portion 24a fitted in the groove 52a may protrude from the guard portion 50c toward the bottom 32 side.

[0163] Even if the guard portion 50c is open on the bottom 32 side, as shown in Figure 8, the linear branch portion 24a fitted in the groove 52a does not have to protrude from the guard portion 50c toward the bottom 32 side.

[0164] Since the guard portion 50d is open on the bottom 32 side, the linear branch portion 24b fitted in the groove 52b may protrude from the guard portion 50d toward the bottom 32 side.

[0165] Even if the guard portion 50d is open on the bottom 32 side, as shown in FIG. 8, the linear branch portion 24b fitted in the groove 52b does not have to protrude from the guard portion 50d toward the bottom 32 side.

[0166] For each of guard portions 50c and 50d, as long as the side facing the lead-out terminal 20 in the third direction D3 is open, at least one of the side facing the bottom 32 in the first direction D1 and the side opposite the lead-out terminal 20 in the third direction D3 may be closed and not open.

[0167] [Embodiment 4] In a capacitor according to embodiment 4 of the present invention, the external electrodes include a first external electrode provided on one end surface of the element body and a second external electrode provided on the other end surface of the element body, and the lead-out terminals include a first lead-out terminal electrically connected to the first external electrode and a second lead-out terminal electrically connected to the second external electrode.

[0168] In the capacitor of embodiment 4 of the present invention, the first lead-out terminal and the second lead-out terminal each have a first surface facing the outer surface of the side wall portion in the second direction, and a second surface facing the first surface in the second direction.

[0169] In the capacitor of embodiment 4 of the present invention, the guard portion includes a first guard portion facing the second surface of the first lead-out terminal in the second direction, and a second guard portion facing the second surface of the second lead-out terminal in the second direction.

[0170] The capacitor of the fourth embodiment of the present invention is similar to the capacitors of the first to third embodiments of the present invention except for the above points.

[0171] FIG. 9 is a perspective schematic view showing an example of a capacitor according to a fourth embodiment of the present invention.

[0172] The capacitor 4 shown in FIG. 9 has a first lead-out terminal 20A and a second lead-out terminal 20B as lead-out terminals.

[0173] The first lead terminal 20A is electrically connected to the first external electrode 12a (see FIGS. 3 and 4).

[0174] The first lead terminal 20A is bent and drawn out from the opening 31 to the outer surface 33a of the side wall 33. After being drawn out from the opening 31 to the outer surface 33a of the side wall 33, the first lead terminal 20A extends from the opening 31 side toward the bottom 32 side in the first direction D1. After extending from the opening 31 side toward the bottom 32 side in the first direction D1, the first lead terminal 20A is connected to the connection object 100A. As a result, the capacitor element 10 is electrically connected to the connection object 100A via the first lead terminal 20A.

[0175] The first drawn-out terminal 20A has a first surface 20Aa facing the outer surface 33a of the side wall portion 33 in the second direction D2, and a second surface 20Ab facing the first surface 20Aa in the second direction D2. In other words, the first surface 20Aa of the first drawn-out terminal 20A faces the outer surface 33a of the side wall portion 33 in the second direction D2, but the second surface 20Ab of the first drawn-out terminal 20A does not face the outer surface 33a of the side wall portion 33.

[0176] The first surface 20Aa of the first lead terminal 20A may be in contact with the outer surface 33a of the side wall portion 33 in the second direction D2, or may be spaced apart from the outer surface 33a of the side wall portion 33 in the second direction D2.

[0177] The second lead terminal 20B is electrically connected to the second external electrode 12b (see FIGS. 3 and 4).

[0178] The second lead-out terminal 20B is bent and drawn out from the opening 31 to the outer surface 33a of the side wall 33. After being drawn out from the opening 31 to the outer surface 33a of the side wall 33, the second lead-out terminal 20B extends from the opening 31 side toward the bottom 32 side in the first direction D1. After extending from the opening 31 side toward the bottom 32 side in the first direction D1, the second lead-out terminal 20B is connected to the connection object 100B. As a result, the capacitor element 10 is electrically connected to the connection object 100B via the second lead-out terminal 20B.

[0179] The second lead-out terminal 20B has a first surface 20Ba facing the outer surface 33a of the side wall portion 33 in the second direction D2, and a second surface 20Bb facing the first surface 20Ba in the second direction D2. In other words, the first surface 20Ba of the second lead-out terminal 20B faces the outer surface 33a of the side wall portion 33 in the second direction D2, but the second surface 20Bb of the second lead-out terminal 20B does not face the outer surface 33a of the side wall portion 33.

[0180] The first surface 20Ba of the second lead terminal 20B may be in contact with the outer surface 33a of the side wall portion 33 in the second direction D2, or may be spaced apart from the outer surface 33a of the side wall portion 33 in the second direction D2.

[0181] When viewed from the second direction D2, the first drawn-out terminal 20A and the second drawn-out terminal 20B preferably overlap. In the example shown in Fig. 9, the first drawn-out terminal 20A overlaps the second drawn-out terminal 20B on the side opposite the outer surface 33a of the side wall portion 33 in the second direction D2. Note that the first drawn-out terminal 20A may also overlap the second drawn-out terminal 20B on the side of the outer surface 33a of the side wall portion 33 in the second direction D2.

[0182] When viewed from the second direction D2, if the first lead-out terminal 20A and the second lead-out terminal 20B overlap, the area in which the first lead-out terminal 20A and the second lead-out terminal 20B are provided is smaller than when the first lead-out terminal 20A and the second lead-out terminal 20B do not overlap, making it possible to reduce the size of the capacitor 4.

[0183] When viewed from the second direction D2, the first lead-out terminal 20A and the second lead-out terminal 20B do not have to overlap.

[0184] An insulating member 60 is provided between the first lead terminal 20A and the second lead terminal 20B to ensure insulation therebetween.

[0185] Examples of the constituent material of the insulating member 60 include resin.

[0186] The outer surface 33a of the side wall portion 33 is provided with a first guard portion 50A and a second guard portion 50B.

[0187] The first guard portion 50A faces the second surface 20Ab of the first lead terminal 20A in the second direction D2.

[0188] In the example shown in Figure 9, the first guard portion 50A surrounds at least a portion of the second surface 20Ab of the first drawn-out terminal 20A and is arranged so as to overlap the first drawn-out terminal 20A when viewed from the second direction D2.

[0189] The second surface 20Ab of the first lead terminal 20A may be in contact with the first guard portion 50A in the second direction D2, or may be spaced apart from the first guard portion 50A in the second direction D2.

[0190] In the capacitor 4, as described above, the first guard portion 50A is provided for the first lead-out terminal 20A, which suppresses movement of the first lead-out terminal 20A in a direction away from the outer case 30 due to springback. As a result, in the capacitor 4, even if springback occurs in the first lead-out terminal 20A, the connection position of the first lead-out terminal 20A relative to the connection target 100A is less likely to shift.

[0191] The first lead terminal 20A is locked to the first guard portion 50A. Specifically, this is as follows.

[0192] The first guard portion 50A is provided with a groove 52A extending in the third direction D3. In the example shown in Fig. 9, the first guard portion 50A includes a first guard portion 50Aa and a first guard portion 50Ab that are provided at positions spaced apart from each other in the third direction D3. In the example shown in Fig. 9, the first guard portion 50Aa is provided with a groove 52Aa extending in the third direction D3, and the first guard portion 50Ab is provided with a groove 52Ab extending in the third direction D3.

[0193] The first lead terminal 20A has a main portion 22A extending in the first direction D1 and a linear branch portion 24A branching linearly from the main portion 22A so that the tip thereof faces the first guard portion 50A in the third direction D3. In the example shown in Fig. 9, the linear branch portion 24A includes a linear branch portion 24Aa branching to one side of the main portion 22A in the third direction D3 and a linear branch portion 24Ab branching to the other side of the third direction D3.

[0194] The linear branch portion 24A is fitted into the groove 52A. In the example shown in Fig. 9, the linear branch portion 24Aa is fitted into the groove 52Aa, and the linear branch portion 24Ab is fitted into the groove 52Ab. In this manner, the first lead-out terminal 20A is engaged with the first guard portion 50A, and in the example shown in Fig. 9, the first guard portion 50Aa and the first guard portion 50Ab.

[0195] The second guard portion 50B faces the second surface 20Bb of the second lead terminal 20B in the second direction D2.

[0196] In the example shown in Figure 9, the second guard portion 50B surrounds at least a portion of the second surface 20Bb of the second drawn-out terminal 20B and is arranged to overlap the second drawn-out terminal 20B when viewed from the second direction D2.

[0197] The second surface 20Bb of the second lead terminal 20B may be in contact with the second guard portion 50B in the second direction D2, or may be spaced apart from the second guard portion 50B in the second direction D2.

[0198] In the capacitor 4, as described above, the second guard portion 50B is provided for the second lead-out terminal 20B, which suppresses movement of the second lead-out terminal 20B in a direction away from the outer case 30 due to springback. As a result, in the capacitor 4, even if springback occurs in the second lead-out terminal 20B, the connection position of the second lead-out terminal 20B relative to the connection object 100B is less likely to shift.

[0199] The second lead terminal 20B is locked to the second guard portion 50B. Specifically, this is as follows.

[0200] A hole 51B is provided in the second guard portion 50B on the side of the opening 31 in the first direction D1. In the example shown in Fig. 9, the second guard portion 50B includes a second guard portion 50Ba and a second guard portion 50Bb that are provided at positions spaced apart from each other in the third direction D3. In the example shown in Fig. 9, the second guard portion 50Ba is provided with a hole 51Ba on the side of the opening 31 in the first direction D1, and the second guard portion 50Bb is provided with a hole 51Bb on the side of the opening 31 in the first direction D1.

[0201] The second lead terminal 20B has a main portion 22B extending in the first direction D1 and a hooked branch portion 23B branching off from the main portion 22B in a hook-like shape so that the tip thereof faces the bottom portion 32 in the first direction D1. In the example shown in Fig. 9, the hooked branch portion 23B includes a hooked branch portion 23Ba branching off on one side in the third direction D3 with respect to the main portion 22B, and a hooked branch portion 23Bb branching off on the other side in the third direction D3.

[0202] The hooked branch portion 23B is inserted into the hole 51B. In the example shown in Fig. 9, the hooked branch portion 23Ba is inserted into the hole 51Ba, and the hooked branch portion 23Bb is inserted into the hole 51Bb. In this manner, the second lead-out terminal 20B is engaged with the second guard portion 50B, or in the example shown in Fig. 9, the second guard portion 50Ba and the second guard portion 50Bb.

[0203] As described above, in the capacitor 4, the first guard portion 50A and the second guard portion 50B prevent the first and second drawn-out terminals 20A and 20B from moving in a direction away from the exterior case 30. Therefore, in the capacitor 4, when the first and second drawn-out terminals 20A and 20B overlap when viewed from the second direction D2 as described above, the spacing between the first and second drawn-out terminals 20A and 20B is likely to be kept uniform. This makes it easier to reduce the equivalent series inductance (ESL) of the first and second drawn-out terminals 20A and 20B in the capacitor 4.

[0204] 9 shows an example in which the first drawn-out terminal 20A is locked to the first guard portion 50A and the second drawn-out terminal 20B is locked to the second guard portion 50B, but either the first drawn-out terminal 20A or the second drawn-out terminal 20B may be locked to the first guard portion 50A or the second drawn-out terminal 20B may be locked to the second guard portion 50B. In particular, as shown in FIG. 9 , when the first drawn-out terminal 20A overlaps the second drawn-out terminal 20B on the side opposite the outer surface 33a of the side wall portion 33 when viewed from the second direction D2, as long as the first drawn-out terminal 20A is locked to the first guard portion 50A, the first drawn-out terminal 20A functions as a guard portion for the second drawn-out terminal 20B even if the second drawn-out terminal 20B is not locked to the second guard portion 50B, and therefore, movement of the second drawn-out terminal 20B in a direction away from the outer case 30 is suppressed by the first drawn-out terminal 20A.

[0205] [Embodiment 5] In Embodiments 1 to 4, a single capacitor element is housed inside a single exterior case, but multiple capacitor elements may be housed inside a single exterior case. Below, an example of a capacitor according to Embodiment 5 of the present invention, in which multiple capacitor elements are housed inside a single exterior case, will be described.

[0206] The capacitor of the fifth embodiment of the present invention is similar to the capacitors of the first to fourth embodiments of the present invention except for the above points.

[0207] FIG. 10 is a schematic perspective view showing an example of a capacitor according to a fifth embodiment of the present invention.

[0208] 10 , a capacitor 5 has a plurality of capacitor elements 10 housed inside a single exterior case 30. While Fig. 10 shows an embodiment in which two capacitor elements 10 are housed inside a single exterior case 30, three or more capacitor elements 10 may be housed inside a single exterior case 30.

[0209] In capacitor 5, similar to capacitor 4, first lead-out terminal 20A and second lead-out terminal 20B are drawn out from each capacitor element 10 to the outside of outer case 30. In capacitor 5, similar to capacitor 4, first lead-out terminal 20A and second lead-out terminal 20B drawn out from outer case 30 extend along outer surface 33a of side wall portion 33, and are then connected to connection object 100A and connection object 100B, respectively.

[0210] In the capacitor 5, the first lead-out terminal 20A and the second lead-out terminal 20B are respectively engaged with the first guard portion 50A and the second guard portion 50B, similarly to the capacitor 4.

[0211] In the example shown in Figure 10, for first drawn-out terminals 20A adjacent to each other in the third direction D3, the first guard portion 50Ab that engages one of the first drawn-out terminals 20A (the first drawn-out terminal 20A on the right in Figure 10) and the first guard portion 50Aa that engages the other first drawn-out terminal 20A (the first drawn-out terminal 20A on the left in Figure 10) are connected to each other in the third direction D3, but may also be spaced apart from each other in the third direction D3.

[0212] In addition, in the example shown in Figure 10, for second pull-out terminals 20B adjacent to each other in the third direction D3, the second guard portion 50Bb that engages one second pull-out terminal 20B (in Figure 10, the second pull-out terminal 20B on the right) and the second guard portion 50Ba that engages the other second pull-out terminal 20B (in Figure 10, the second pull-out terminal 20B on the left) are spaced apart from each other in the third direction D3, but may also be connected to each other in the third direction D3.

[0213] [Other Embodiments] In the first to fifth embodiments, the guard portion faces a portion of the second surface of the pull-out terminal, but the guard portion may face the entire second surface of the pull-out terminal. For example, the guard portion may surround the entire second surface of the pull-out terminal from the opening side to the bottom side in the first direction.

[0214] The capacitor of the present invention is not limited to the above-described embodiment, and various applications and modifications can be made within the scope of the present invention with respect to the configuration of the capacitor, manufacturing conditions, and the like.

[0215] For example, in the capacitor of the present invention, the shape, number, etc. of the lead terminals are not limited to those in the above embodiment.

[0216] Furthermore, in the capacitor of the present invention, the shape, number, etc. of the guard portion are not limited to those in the above embodiment.

[0217] The capacitor of the present invention is useful for power conversion devices such as motor drive inverters mounted on electric vehicles.

[0218] The present specification discloses the following:

[0219] <1> A capacitor comprising: a capacitor element having an element body and an external electrode provided on an end surface of the element body; a lead-out terminal electrically connected to the external electrode; and an exterior case in which the capacitor element is housed, wherein the exterior case is a bottomed cylindrical shape having an opening, and has a bottom facing the opening in a first direction, and a side wall extending in the first direction from the bottom toward the opening, wherein the lead-out terminal is led out from the opening to an outer surface of the side wall while being bent, and extends from the opening side toward the bottom side in the first direction, wherein the lead-out terminal has a first surface facing the outer surface of the side wall in a second direction perpendicular to the outer surface of the side wall, and a second surface opposite the first surface in the second direction, wherein a guard portion is provided on the outer surface of the side wall, facing the second surface of the lead-out terminal in the second direction.

[0220] <2> The capacitor according to <1>, wherein the guard portion protrudes from the side wall portion in the second direction.

[0221] <3> The capacitor according to <1> or <2>, wherein the guard portion is integrated with the side wall portion.

[0222] <4> The capacitor according to any one of <1> to <3>, wherein the lead-out terminal is engaged with the guard portion.

[0223] <5> The capacitor described in <4>, wherein the guard portion has a hole on the opening side in the first direction, the pull-out terminal has a main portion extending in the first direction and a hook-shaped branch portion branching off from the main portion in a hook shape with a tip facing the bottom side in the first direction, and the hook-shaped branch portion is inserted into the hole.

[0224] <6> The capacitor described in <4>, wherein the guard portion has a groove extending in a third direction perpendicular to the first direction and the second direction, the pull-out terminal has a main portion extending in the first direction and a linear branch portion branching linearly from the main portion so that a tip thereof faces the guard portion side in the third direction, and the linear branch portion is fitted in the groove.

[0225] <7> The capacitor according to any one of <1> to <6>, wherein the external electrodes include a first external electrode provided on one end surface of the element body and a second external electrode provided on the other end surface of the element body, and the lead-out terminals include a first lead-out terminal electrically connected to the first external electrode and a second lead-out terminal electrically connected to the second external electrode.

[0226] <8> The capacitor described in <7>, wherein the first lead-out terminal and the second lead-out terminal each have a first surface facing the outer surface of the side wall portion in the second direction and a second surface facing the first surface in the second direction, and the guard portion includes a first guard portion facing the second surface of the first lead-out terminal in the second direction and a second guard portion facing the second surface of the second lead-out terminal in the second direction.

[0227] <9> The capacitor according to <7> or <8>, wherein the first lead terminal and the second lead terminal overlap when viewed from the second direction.

[0228] <10> The capacitor according to any one of <1> to <9>, wherein in the first direction, the distance between the bottom and the guard portion is equal to or less than half the distance between the bottom and the opening.

[0229] <11> The capacitor according to any one of <1> to <10>, further comprising a filling resin filled inside the exterior case so as to bury the capacitor element.

[0230] 1, 1', 2, 3, 3', 4, 5 Capacitor 10 Capacitor element 11 Body 12a First external electrode 12b Second external electrode 13a First metallized film 13b Second metallized film 14a First dielectric film 14aa First main surface of first dielectric film 14ab Second main surface of first dielectric film 14b Second dielectric film 14ba First main surface of second dielectric film 14bb Second main surface of second dielectric film 15a First metal layer 15b Second metal layer 20 Lead terminal 20a First surface of lead terminal 20b Second surface of lead terminal 20A First lead terminal 20Aa First surface of first lead terminal 20Ab Second surface of first lead terminal 20B Second lead terminal 20Ba First surface of second lead terminal 20Bb Second surface 21a, 21b of second lead terminal Bent portion 22, 22A, 22B Main portion 23, 23a, 23b, 23B, 23Ba, 23Bb Hook-shaped branch portion 24, 24a, 24b, 24A, 24Aa, 24Ab Straight branch portion 30 Outer case 31 Opening 32 Bottom 33 Side wall portion 33a Outer surface of side wall portion 40 Filled resin 50, 50a, 50b, 50c, 50d Guard portion 50A, 50Aa, 50Ab First guard portion 50B, 50Ba, 50Bb Second guard portion 51, 51a, 51b, 51B, 51Ba, 51Bb Hole 52, 52a, 52b, 52A, 52Aa, 52Ab Groove 60 Insulating member 100, 100A, 100B Connection object D1 First direction D2 Second direction D3 Third direction

Claims

1. A capacitor comprising: a capacitor element having an element body and an external electrode provided on an end face of the element body; a pull-out terminal electrically connected to the external electrode; and an exterior case in which the capacitor element is housed, wherein the exterior case is tubular with a bottom and has an opening, a bottom facing the opening in a first direction, and a side wall extending in the first direction from the bottom toward the opening, wherein the pull-out terminal is pulled out from the opening to an outer surface of the side wall while being bent, and extends from the opening side toward the bottom side in the first direction, wherein the pull-out terminal has a first surface facing the outer surface of the side wall in a second direction perpendicular to the outer surface of the side wall, and a second surface opposite to the first surface in the second direction, wherein a guard portion is provided on the outer surface of the side wall, facing the second surface of the pull-out terminal in the second direction.

2. The capacitor according to claim 1, wherein the guard portion protrudes from the side wall portion in the second direction.

3. The capacitor according to claim 1 or 2, wherein the guard portion is integral with the side wall portion.

4. A capacitor according to any one of claims 1 to 3, wherein the lead-out terminal is engaged with the guard portion.

5. The capacitor described in claim 4, wherein the guard portion has a hole on the side of the opening in the first direction, the pull-out terminal has a main portion extending in the first direction and a hook-shaped branch portion branching off from the main portion in a hook shape with its tip facing the bottom side in the first direction, and the hook-shaped branch portion is inserted into the hole.

6. The capacitor described in claim 4, wherein the guard portion is provided with a groove extending in a third direction perpendicular to the first direction and the second direction, the pull-out terminal has a main portion extending in the first direction and a linear branch portion branching out in a straight line from the main portion so that a tip thereof faces the guard portion side in the third direction, and the linear branch portion is fitted in the groove.

7. A capacitor as claimed in any one of claims 1 to 6, wherein the external electrodes include a first external electrode provided on one end face of the element body and a second external electrode provided on the other end face of the element body, and the lead-out terminals include a first lead-out terminal electrically connected to the first external electrode and a second lead-out terminal electrically connected to the second external electrode.

8. The capacitor described in claim 7, wherein the first pull-out terminal and the second pull-out terminal each have a first surface facing the outer surface of the side wall portion in the second direction and a second surface opposing the first surface in the second direction, and the guard portion includes a first guard portion facing the second surface of the first pull-out terminal in the second direction and a second guard portion facing the second surface of the second pull-out terminal in the second direction.

9. The capacitor according to claim 7 or 8, wherein the first lead-out terminal and the second lead-out terminal overlap when viewed from the second direction.

10. A capacitor according to any one of claims 1 to 9, wherein in the first direction, the distance between the bottom and the guard portion is equal to or less than half the distance between the bottom and the opening.

11. The capacitor according to claim 1, further comprising a filling resin filled inside the exterior case so as to embed the capacitor element.

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