Capacitor

Abstract

This film capacitor is provided with: a capacitor element that has a first electrode on one end surface and a second electrode on the other end surface; a first bus bar (200) and a second bus bar (300) that are respectively connected to the first electrode and the second electrode; a case (400) that is formed of a resin material and houses the capacitor element; and a filling resin that is filled inside the case (400). The case (400) includes: an opening part (410); a bottom surface part (420) that faces the opening part (410); and a first side surface part (430) that extends from an edge part of the bottom surface part (420) toward the opening part (410) side. The first bus bar (200) constitutes a part of the first side surface part (430), and has a first electrode terminal part (210) that is exposed to the outside of the case (400) in the first side surface part (430).

Description

capacitor

[0001] The present invention relates to a capacitor.

[0002] Conventionally, case-molded capacitors have been known in which a resin case containing a capacitor element is filled with a filling resin to enhance shock resistance and moisture resistance. In such capacitors, when the capacitor element generates heat, the heat is difficult to dissipate to the outside of the case.

[0003] Therefore, in order to facilitate the dissipation of heat from the capacitor element to the outside of the case, a metal plate can be insert-molded onto the side or bottom of the case so that its outer surface is exposed to the outside. A capacitor with such a configuration is described, for example, in Patent Document 1.

[0004] International Publication No. 2021 / 014927

[0005] In the capacitor of Patent Document 1, heat from the capacitor element on the side having the metal plate is dissipated to the outside of the case along a heat dissipation path made up of three materials: the bus bar connected to the electrode of the capacitor element, the filled resin, and the metal plate. However, if the heat dissipation path from the capacitor element were shorter, it would be possible to more efficiently dissipate the heat generated by the capacitor element to the outside of the case.

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a capacitor that can shorten the heat dissipation path from the capacitor element and efficiently dissipate heat to the outside of the case.

[0007] A first aspect of the present invention relates to a capacitor. The capacitor according to this aspect includes a capacitor element having a first electrode on one end surface and a second electrode on the other end surface, a first bus bar and a second bus bar connected to the first electrode and the second electrode, respectively, a case formed of a resin material and housing the capacitor element, and a filled resin filling the case. The case includes an opening, a first surface facing the opening, and a second surface extending from an edge of the first surface toward the opening. At least the first bus bar has a first case-constituting portion that forms at least a portion of one of the first and second surfaces and is exposed to the outside of the case at the one surface.

[0008] According to the present invention, it is possible to provide a capacitor that can shorten the heat dissipation path from the capacitor element and efficiently dissipate heat to the outside of the case.

[0009] The effects and significance of the present invention will become more apparent from the following description of the embodiments, however, the embodiments shown below are merely examples of how the present invention can be implemented, and the present invention is not limited to the embodiments described below.

[0010] FIG. 1 is a perspective view of a film capacitor according to the first embodiment, with the bottom surface of the case facing upward. FIG. 2 is a perspective view of a film capacitor according to the first embodiment, with the opening of the case facing upward. FIG. 3 is a perspective view of a film capacitor according to the first embodiment, with the opening of the case facing upward and not filled with a filling resin. FIG. 4 is a perspective view of three capacitor elements according to the first embodiment. FIG. 5 is a perspective view of a first bus bar according to the first embodiment. FIG. 6 is a perspective view of a second bus bar according to the first embodiment. FIG. 7 is a perspective view of a case according to the first embodiment, with the bottom surface facing upward, and the first and second bus bars integrated with the case. FIG. 8 is a perspective view of a case according to the first embodiment, with the opening facing upward, and the first and second bus bars integrated with the case. FIGS. 9(a) and 9(b) are cross-sectional views of a case according to the first embodiment, taken along lines A-A' and B-B' in FIG. 7, respectively. FIG. 10 is a cross-sectional view of a case according to the first embodiment, taken along line CC' in FIG. 7 . FIG. 11 is a diagram illustrating a manufacturing process flow for a film capacitor according to the first embodiment. FIGS. 12(a) to 12(c) are diagrams illustrating the manufacturing process for a film capacitor according to the first embodiment. FIG. 13 is a diagram illustrating a film capacitor with a cooling device attached according to the first embodiment. FIG. 14(a) is a diagram illustrating a film capacitor according to the second embodiment, viewed from the front of the opening. FIG. 14(b) is a diagram illustrating a film capacitor according to the second embodiment, viewed from the front of the bottom. FIGS. 15(a) and 15(b) are cross-sectional views of a film capacitor according to the second embodiment, taken along line DD' and line EE' in FIG. 14(a), respectively. FIG. 16 is a perspective view of a film capacitor according to the third embodiment, with the bottom of the case facing upward. FIG. 17 is a perspective view of a film capacitor according to the third embodiment, with the opening of the case facing upward. FIG. 18 is a perspective view of a first bus bar and a second bus bar according to the third embodiment. FIG. 19(a) is a plan view of a case according to embodiment 3, seen from the opening side, and FIG. 19(b) is a plan view of a case according to embodiment 3, in which a plurality of capacitor elements are housed, seen from the opening side.Fig. 20(a) is a cross-sectional view taken along line D-D' in Fig. 19(a) according to the third embodiment, and Fig. 20(b) is a cross-sectional view taken along line E-E' in Fig. 19(b) according to the third embodiment. Figs. 21(a) to 21(c) are diagrams for explaining a film capacitor according to a modified example. Figs. 22(a) and 22(b) are diagrams for explaining a film capacitor according to a modified example. Figs. 23(a) to 23(e) are diagrams for explaining a film capacitor according to a modified example.

[0011] However, the drawings are for illustrative purposes only and do not limit the scope of the present invention.

[0012] A film capacitor, which is one embodiment of a capacitor of the present invention, will be described below with reference to the drawings. For convenience, each drawing is labeled with an X-axis, a Y-axis, and a Z-axis, which are orthogonal to each other. The Z-axis is the direction in which the opening and bottom of the case are aligned.

[0013] First Embodiment A film capacitor 1 according to a first embodiment will be described.

[0014] In this embodiment, the film capacitor 1 corresponds to the "capacitor" in the claims. The bottom surface portion 420 corresponds to the "first surface portion" in the claims. The first side surface portion 430 corresponds to the "second surface portion" in the claims. The second side surface portion 440 corresponds to the "third surface portion" in the claims. The first electrode terminal portion 210 corresponds to the "first case component" and "part of the first bus bar" in the claims. The second electrode terminal portion 310 corresponds to the "second case component" and "part of the second bus bar" in the claims.

[0015] However, the above description is merely intended to match the configuration of the claims with the configuration of the embodiments, and the above correspondence does not in any way limit the invention described in the claims to the configuration of the embodiments.

[0016] FIG. 1 is a perspective view of the film capacitor 1 with the bottom surface 420 of the case 400 facing upward. FIG. 2 is a perspective view of the film capacitor 1 with the opening 410 of the case 400 facing upward. FIG. 3 is a perspective view of the film capacitor 1 with the opening 410 of the case 400 facing upward and not filled with a filling resin 500. FIG. 4 is a perspective view of three capacitor elements 100. FIG. 5 is a perspective view of the first bus bar 200. FIG. 6 is a perspective view of the second bus bar 300. FIG. 7 is a perspective view of the case 400 with the bottom surface 420 facing upward, and the first bus bar 200 and the second bus bar 300 integrated with the case 400. FIG. 8 is a perspective view of the case 400 with the opening 410 facing upward, and the first bus bar 200 and the second bus bar 300 integrated with the case 400. 9(a) and 9(b) are cross-sectional views of the case 400 taken along lines A-A' and B-B' in Fig. 7, respectively. Fig. 10 is a cross-sectional view of the case 400 taken along line CC' in Fig. 7.

[0017] The film capacitor 1 includes three capacitor elements 100 , a first bus bar 200 , a second bus bar 300 , a case 400 , and a filling resin 500 .

[0018] Capacitor element 100 is formed into a shape similar to a flattened elongated cylinder by stacking two metallized films, each consisting of a dielectric film and aluminum vapor-deposited on the other, and then rolling or laminating the stacked metallized films and pressing them together. Capacitor element 100 has first electrode 110 formed on one end face by spraying a metal such as zinc, and second electrode 120 formed on the other end face by spraying a metal such as zinc.

[0019] Although capacitor element 100 of this embodiment is formed from a metallized film in which aluminum is vapor-deposited on a dielectric film, it may also be formed from a metallized film in which other metals such as zinc, magnesium, etc. Alternatively, capacitor element 100 may be formed from a metallized film in which multiple metals selected from these metals are vapor-deposited, or from a metallized film in which an alloy of these metals is vapor-deposited.

[0020] The first bus bar 200 is formed by appropriately cutting out and bending a conductive material, for example, a copper plate, and has a configuration in which a first electrode terminal portion 210, a first relay portion 220, and four first connection terminal portions 230 are integrated together.

[0021] The first electrode terminal 210 has a substantially rectangular plate shape that is long in the Y-axis direction. Both surfaces of the first electrode terminal 210 face the X-axis direction. Three I-shaped first terminals 211 are arranged in the Y-axis direction on the first electrode terminal 210 by hollowing out a semicircle around the first terminal 211 in the first electrode terminal 210, i.e., on both sides in the Y-axis direction. The hollowed-out portion becomes a circular first borehole 212 divided into two semicircles by the first terminal 211. A first outer peripheral region 213 having a circular ring shape is formed around the outer periphery of the first borehole 212. The thicknesses of the first terminals 211 and the first outer peripheral region 213 are smaller than the thickness of the periphery of the first outer peripheral region 213 in the first electrode terminal 210. As a result, the heat capacity of first terminal 211 and first outer peripheral region 213 is smaller than when they have the same thickness as the surrounding area of ​​first outer peripheral region 213. Furthermore, multiple holes 214 are formed in first outer peripheral region 213, further reducing the heat capacity. Because the thickness of first terminal 211 and first outer peripheral region 213 is smaller, their surfaces are recessed relative to the surrounding surface of first outer peripheral region 213.

[0022] The first bored hole 212 is a first through hole that penetrates the first electrode terminal portion 210 in the X-axis direction, and the first outer peripheral region 213 is the periphery of the first through hole. The periphery of the first through hole (first outer peripheral region 213) and the first terminal 211 form a first terminal portion. The first terminal 211 is located inside the first through hole (first bored hole 212) and is connected to the periphery of the first through hole. The first through hole (first bored hole 212) and the first terminal portion form a first bonding portion that is bonded to the first electrode 110 of each capacitor element 100.

[0023] The first relay portion 220 relays between the first electrode terminal 210 and the four first connection terminals 230. The first relay portion 220 includes a first main body portion 221 and a first overlapping portion 222. The first main body portion 221 has a generally rectangular plate shape that is elongated in the Y-axis direction, and extends in the negative X-axis direction from the edge of the first electrode terminal 210 in the positive Z-axis direction. The width of the first main body portion 221 in the X-axis direction narrows on the negative Y-axis side. The first overlapping portion 222 has a generally rectangular plate shape that is elongated in the Y-axis direction, and extends in the positive Z-axis direction from the edge of the first main body portion 221 in the negative X-axis direction.

[0024] The four first connection terminals 230 have a substantially rectangular plate shape. A circular mounting hole 231 is formed at the tip of each first connection terminal 230. The first connection terminal 230 furthest in the negative Y-axis direction is longer in the Z-axis direction than the other three first connection terminals 230, and its mounting hole 231 is larger than those of the other three first connection terminals 230.

[0025] The three first connection terminals 230 on the positive Y-axis side extend in the positive Z-axis direction from the edge of the first overlapping portion 222 in the positive Z-axis direction. The first connection terminal 230 on the most negative Y-axis side extends in the positive Z-axis direction from the edge of the first main body portion 221 in the negative X-axis direction. The four first connection terminals 230 are arranged at predetermined intervals in the Y-axis direction.

[0026] The second bus bar 300 is formed by appropriately cutting out and bending a conductive material, for example, a copper plate, and has a configuration in which a second electrode terminal portion 310, a second relay portion 320, and four second connection terminal portions 330 are integrated together.

[0027] The second electrode terminal 310 has a substantially rectangular plate shape that is elongated in the Y-axis direction. Both surfaces of the second electrode terminal 310 face the X-axis direction. Three I-shaped second terminals 311 are arranged in the Y-axis direction on the second electrode terminal 310 by hollowing out a semicircle around the second terminal 311 in the second electrode terminal 310, i.e., on both sides in the Y-axis direction. The hollowed-out portion becomes a circular second borehole 312 divided into two semicircles by the second terminal 311. A second outer peripheral region 313 having a circular ring shape is formed around the outer periphery of the second borehole 312. The thickness of the second terminals 311 and the second outer peripheral region 313 is smaller than the thickness of the periphery of the second electrode terminal 310 around the second outer peripheral region 313. As a result, the heat capacity of the second terminal 311 and the second outer peripheral region 313 is smaller than when they have the same thickness as the surrounding area of ​​the second outer peripheral region 313. Furthermore, the second outer peripheral region 313 has a plurality of holes 314 formed therein, which further reduces the heat capacity. Because the thickness of the second terminal 311 and the second outer peripheral region 313 is smaller, the surfaces of the second terminal 311 and the second outer peripheral region 313 are recessed relative to the surrounding surface of the second outer peripheral region 313.

[0028] The second bored hole 312 is a second through hole that penetrates the second electrode terminal portion 310 in the X-axis direction, and the second outer peripheral region 313 is the periphery of the second through hole. The periphery of the second through hole (second outer peripheral region 313) and the second terminal 311 form a second terminal portion. The second terminal 311 is located inside the second through hole (second bored hole 312) and is connected to the periphery of the second through hole. The second through hole (second bored hole 312) and the second terminal portion form a second bonding portion that is bonded to the second electrode 120 of each capacitor element 100.

[0029] The second relay portion 320 relays between the second electrode terminal 310 and the four second connection terminals 330. The second relay portion 320 includes a second main body portion 321 and a second overlapping portion 322. The second main body portion 321 has a generally rectangular plate shape that is elongated in the Y-axis direction, and extends in the positive X-axis direction from the edge of the second electrode terminal 310 in the positive Z-axis direction. The second overlapping portion 322 has a generally rectangular plate shape that is elongated in the Y-axis direction, and extends in the positive Z-axis direction from the edge of the second main body portion 321 in the positive X-axis direction.

[0030] The four second connection terminals 330 have a substantially rectangular plate shape. A circular mounting hole 331 is formed at the tip of each second connection terminal 330. The second connection terminal 330 closest to the negative Y-axis side is longer in the Z-axis direction than the other three second connection terminals 330, and has a larger mounting hole 331 than the other three second connection terminals 330. Furthermore, the tip of the second connection terminal 330 closest to the negative Y-axis side bulges in the negative Y-axis direction.

[0031] The three second connection terminals 330 on the positive Y-axis side extend in the positive Z-axis direction from the edge of the second overlapping portion 322 in the positive Z-axis direction. The second connection terminal 330 on the most negative Y-axis side extends in the positive Z-axis direction from the edge of the second main body portion 321 in the positive X-axis direction. The four second connection terminals 330 are arranged at predetermined intervals in the Y-axis direction.

[0032] The case 400 is made of a resin material, for example, a thermoplastic resin such as polyphenylene sulfide (PPS). The case 400 may also be made of a thermosetting resin such as an epoxy resin.

[0033] Case 400 has a substantially rectangular box shape and includes a rectangular opening 410, a rectangular bottom surface 420 facing opening 410, rectangular first side surface 430 and second side surface 440 extending from both edges of bottom surface 420 on the X-axis direction toward opening 410 (negative Z-axis direction) and facing each other, and rectangular third side surface 450 and fourth side surface 460 extending from both edges of bottom surface 420 on the Y-axis direction toward opening 410 (negative Z-axis direction) and facing each other. The dimension of case 400 in the Y-axis direction is greater than the dimension in the Z-axis direction, and the dimensions of case 400 in the Y-axis direction and Z-axis directions are greater than the dimension in the X-axis direction.

[0034] First bus bar 200 and second bus bar 300 are insert-molded into case 400 and are integrated with case 400. That is, first bus bar 200 and second bus bar 300 have portions that are embedded in case 400.

[0035] The first side surface portion 430 has a rectangular opening 431 that is long in the Y-axis direction. The opening 431 occupies most of the first side surface portion 430. In other words, the first side surface portion 430 is open except for first end portions 432 that are elongated in the Z-axis direction on both sides of the Y-axis direction, and a second end portion 433 that is elongated in the Y-axis direction and connects the ends of the two first end portions 432 in the negative Z-axis direction.

[0036] The opening 431 of the first side surface portion 430 is blocked by the first electrode terminal portion 210 of the first bus bar 200. That is, the first electrode terminal portion 210, as a first case component, forms a region corresponding to the opening 431 in the first side surface portion 430 and is exposed to the outside of the case 400 at the first side surface portion 430. As shown in FIGS. 9A and 10 , both ends of the first electrode terminal portion 210 in the Y-axis direction are embedded in a first end portion 432 of the first side surface portion 430. On the other hand, as shown in FIG. 9B , the end of the first electrode terminal portion 210 in the negative Z-axis direction is not embedded in a second end portion 433 of the first side surface portion 430. Its outer surface is covered by the second end portion 433, but its inner surface is flush with the inner surface of the second end portion 433. That is, the second end portion 433 does not protrude further inward into the case 400 than the first electrode terminal portion 210.

[0037] The second side surface portion 440 has a rectangular opening 441 that is long in the Y-axis direction. The opening 441 occupies most of the second side surface portion 440. In other words, the second side surface portion 440 is open except for first end portions 442 that are elongated in the Z-axis direction on both sides of the Y-axis direction, and a second end portion 443 that is elongated in the Y-axis direction and connects the ends of the two first end portions 442 in the negative Z-axis direction.

[0038] The opening 441 of the second side surface portion 440 is blocked by the second electrode terminal portion 310 of the second bus bar 300. That is, the second electrode terminal portion 310 constitutes a region corresponding to the opening 441 in the second side surface portion 440 as a second case component, and is exposed to the outside of the case 400 at the second side surface portion 440. As shown in FIGS. 9A and 10 , both ends of the second electrode terminal portion 310 in the Y-axis direction are embedded in the first end 442 of the second side surface portion 440. On the other hand, as shown in FIG. 9B , the end of the second electrode terminal portion 310 in the negative Z-axis direction is not embedded in the second end 443 of the second side surface portion 440. Its outer surface is covered by the second end 443, but its inner surface is flush with the inner surface of the second end 443. That is, the second end 443 does not protrude further inward into the case 400 than the second electrode terminal portion 310.

[0039] 9( a) and 9(b), the first relay portion 220 of the first bus bar 200 and the second relay portion 320 of the second bus bar 300 are embedded in the bottom surface portion 420. Four first connection terminal portions 230 extending from the first relay portion 220 and four second connection terminal portions 330 extending from the second relay portion 320 protrude to the outside from the bottom surface portion 420. The four first connection terminal portions 230 and the four second connection terminal portions 330 are lined up adjacent to each other in the Y-axis direction.

[0040] The bottom surface portion 420 has root portions 421 of the three first connection terminal portions 230 and three second connection terminal portions 330 on the positive Y-axis side, a root portion 422 of the first connection terminal portion 230 on the most negative Y-axis side, and a root portion 423 of the second connection terminal portion 330 on the most negative Y-axis side protruding toward the positive Z-axis side.

[0041] Inside the bottom surface portion 420, the first overlapping portion 222 of the first bus bar 200 and the second overlapping portion 322 of the second bus bar 300 overlap each other in the X-axis direction, sandwiching the insulating resin inside the bottom surface portion 420. This reduces the ESL (equivalent series inductance) of the film capacitor 1.

[0042] The case 400 has a mounting tab 470 on the third side surface portion 450. An insertion hole 471 is formed in the mounting tab 470. A metal collar 472 is fitted into the insertion hole 471 to increase the strength of the hole. When the film capacitor 1 is installed in an installation portion of an external device or the like, the mounting tab 470 is fixed to the installation portion with a screw or the like.

[0043] The three capacitor elements 100 are housed in the case 400 so that one end face, i.e., the first electrode 110, faces the first side surface portion 430, and the other end face, i.e., the second electrode 120, faces the second side surface portion 440. The first electrode terminal portion 210 of the first bus bar 200, which constitutes a part (most of) the first side surface portion 430, covers the three first electrodes 110 and is close to these first electrodes 110. Furthermore, the second electrode terminal portion 310 of the second bus bar 300, which constitutes a part (most of) the second side surface portion 440, covers the three second electrodes 120 and is close to these second electrodes 120.

[0044] The three first terminals 211 of the first electrode terminal portion 210 are joined to the first electrodes 110 corresponding to the respective first terminals 211 with solder S. Furthermore, the three first punched holes 212 of the first electrode terminal portion 210 are closed and sealed with solder S. The solder S protrudes into and covers the first outer peripheral region 213. As a result, the first outer peripheral region 213 is also joined to the first electrode 110 with the solder S.

[0045] The three second terminals 311 of the second electrode terminal portion 310 are joined to the second electrodes 120 corresponding to the respective second terminals 311 with solder S. Furthermore, the three second punched holes 312 of the second electrode terminal portion 310 are closed and sealed with solder S. The solder S protrudes into and covers the second outer peripheral region 313. As a result, the second outer peripheral region 313 is also joined to the second electrode 120 with the solder S.

[0046] In the first electrode terminal 210, the solder S protrudes beyond the peripheral surface of the first outer peripheral region 213, but the amount of protrusion is reduced by the recessed first terminal 211 and the first outer peripheral region 213. Similarly, in the second electrode terminal 310, the solder S protrudes beyond the peripheral surface of the second outer peripheral region 313, but the amount of protrusion is reduced by the recessed second terminal 311 and the second outer peripheral region 313. The amount of recession of the first terminal 211 and the first outer peripheral region 213 may be increased so that the solder S does not protrude beyond the peripheral surface of the first outer peripheral region 213. Similarly, the amount of recession of the second terminal 311 and the second outer peripheral region 313 may be increased so that the solder S does not protrude beyond the peripheral surface of the second outer peripheral region 313.

[0047] The filling resin 500 is a thermosetting resin such as epoxy resin. The filling resin 500 is filled into the case 400 that houses the three capacitor elements 100. Each capacitor element 100 is covered with the filling resin 500, thereby protecting it from moisture and impact.

[0048] Next, a method for manufacturing the film capacitor 1 will be described.

[0049] Fig. 11 is a diagram showing the flow of the manufacturing process of the film capacitor 1. Fig. 12(a) to (c) are diagrams for explaining the manufacturing process of the film capacitor 1.

[0050] First, a preparation step is performed (S1). In the preparation step, the case 400 is prepared. In the case 400, a portion of the first side surface portion 430 is configured by a portion of the first bus bar 200, i.e., the first electrode terminal portion 210, and the first electrode terminal portion 210 is exposed to the outside at the first side surface portion 430. Also, a portion of the second side surface portion 440 is configured by a portion of the second bus bar 300, i.e., the second electrode terminal portion 310, and the second electrode terminal portion 310 is exposed to the outside at the second side surface portion 440 (see FIGS. 7 and 8 ).

[0051] Next, the accommodating step is performed (S2). In this accommodating step, as shown in FIG. 12( a), three capacitor elements 100 are accommodated in the case 400 through the opening 410. As described above, the second end 433 of the first side surface portion 430 and the second end 443 of the second side surface portion 440 do not protrude into the inside of the case 400, and therefore do not interfere with the accommodated capacitor elements 100. When the three capacitor elements 100 are accommodated in the case 400, the first terminals 211 of the first electrode terminal portion 210 are adjacent to the first electrodes 110 of the three capacitor elements 100, and the second terminals 311 of the second electrode terminal portion 310 are adjacent to the second electrodes 120 of the three capacitor elements 100.

[0052] Next, a bonding step is performed (S3). In the bonding step, as shown in FIG. 12(b), the first bus bars 200 and the second bus bars 300 are respectively soldered to the first electrodes 110 and the second electrodes 120 of the three capacitor elements 100. At this time, the first terminals 211 of the first electrode terminals 210 are joined to the first electrodes 110 with solder S, and the first bore holes 212 of the first electrode terminals 210 are sealed with solder S. Furthermore, the second terminals 311 of the second electrode terminals 310 are joined to the second electrodes 120 with solder S, and the second bore holes 312 of the second electrode terminals 310 are sealed with solder S. As described above, each first terminal 211, each second terminal 311, each first outer region 213 of the first electrode terminal portion 210, and each second outer region 313 of the second electrode terminal portion 310 are configured to have a small heat capacity, so that the temperature of the molten solder S is less likely to drop, and soldering can be performed satisfactorily.

[0053] Finally, the filling step is performed (S4). In the filling step, as shown in FIG. 12(c), liquid-phase filling resin 500 is injected into case 400 through opening 410 and fills the case up to a position close to opening 410. At this time, in first side surface portion 430 and second side surface portion 440, each of first bore holes 212 and each of second bore holes 312 are sealed with solder S, so that liquid-phase filling resin 500 is prevented from leaking out of case 400 through each of first bore holes 212 and each of second bore holes 312. Thereafter, case 400 is heated, whereby filling resin 500 in case 400 is heated and hardened.

[0054] This completes the manufacturing process, resulting in the film capacitor 1 shown in Figures 1 and 2.

[0055] The film capacitor 1 is mounted on an external device, etc. Four pairs of external terminals (not shown) provided on the external device, etc., corresponding to the four sets of first connection terminal portions 230 and second connection terminal portions 330 are connected to these connection terminal portions by screwing using the mounting holes 231, 331. When mounted on the external device, etc., a cooling device 10 can be attached to the film capacitor 1.

[0056] Fig. 13 is a diagram showing the film capacitor 1 to which the cooling device 10 is attached. In Fig. 13, the film capacitor 1 is shown in cross section.

[0057] The film capacitor 1 has cooling devices 10 attached to both the first side surface 430 and the second side surface 440 of the case 400. The cooling device 10 is, for example, a liquid-cooled cooling device in which pipes are arranged inside a jacket made of a metal with high thermal conductivity, such as aluminum, and a coolant, such as water, is passed through the pipes. Alternatively, the cooling device 10 may be a heat dissipation fin formed from a metal with high thermal conductivity in a fin shape. When the cooling device 10 is a heat dissipation fin, the heat dissipation fin may be air-cooled by a fan.

[0058] The two cooling devices 10 are in contact with the first electrode terminal 210 constituting the first side surface 430 and the second electrode terminal 310 constituting the second side surface 440 via insulating heat dissipation sheets 11. The heat dissipation sheets 11 have at least better heat dissipation properties than the filled resin 500. Each heat dissipation sheet 11 is flexible and has a certain thickness. Therefore, the solder S protruding from the surface of the first electrode terminal 210 and the solder S protruding from the surface of the second electrode terminal 310 are absorbed by the thickness of each heat dissipation sheet 11.

[0059] Instead of the heat dissipation sheet 11, grease having excellent insulating and heat dissipating properties may be applied to a certain thickness on the first electrode terminal 210 and the second electrode terminal 310. In this case, the grease is interposed between the two cooling devices 10 and the first electrode terminal 210 and the second electrode terminal 310.

[0060] In the film capacitor 1, when current is applied to each capacitor element 100, the capacitor element 100 may generate heat. The heat generated by each capacitor element 100 is transferred to the first electrode terminal 210 and the second electrode terminal 310. Because the first electrode terminal 210 and the second electrode terminal 310 are exposed to the outside of the case 400 at the first side surface 430 and the second side surface 440, respectively, the heat transferred to the first electrode terminal 210 and the second electrode terminal 310 is immediately released to the outside of the case 400 and absorbed by the cooling device 10 via the heat dissipation sheet 11. This suppresses the temperature rise of each capacitor element 100, making the film capacitor 1 less likely to overheat.

[0061] In this embodiment, the heat dissipation path from capacitor element 100 to the outside of case 400 is substantially only first electrode terminal 210 on the first side surface portion 430 side of case 400, and is substantially only second electrode terminal 310 on the second side surface portion 440 side of case 400. Therefore, since the heat dissipation path is short, heat generated by capacitor element 100 is efficiently dissipated to the outside of case 400.

[0062] In the film capacitor 1, the cooling device 10 may be attached to only one of the first electrode terminal 210 (first side surface portion 430) and the second electrode terminal 310 (second side surface portion 440).

[0063] Furthermore, at least one of the first electrode terminal 210 (first side surface portion 430) and the second electrode terminal 310 (second side surface portion 440) may be in contact with a casing made of a metal with high thermal conductivity, such as aluminum, provided on an external device, etc., via a heat dissipation sheet, etc. In this case, heat released to the outside of the case 400 is transferred to the casing, and dissipated from the casing. At this time, the casing may be cooled by a cooling device.

[0064] Furthermore, for example, when the film capacitor 1 is used in a low-temperature environment or when the amount of heat generated by the capacitor element 100 is small, a cooling device may not be attached to the film capacitor 1. In this case, the first electrode terminal 210 and the second electrode terminal 310 exposed to the outside of the case 400 may be covered with a heat dissipation sheet or the like from the viewpoint of insulation.

[0065] <Effects of First Embodiment> As described above, the first embodiment provides the following effects.

[0066] The film capacitor 1 includes a capacitor element 100 having a first electrode 110 on one end surface and a second electrode 120 on the other end surface, a first bus bar 200 and a second bus bar 300 connected to the first electrode 110 and the second electrode 120, respectively, a case 400 formed of a resin material and accommodating the capacitor element 100, and a filled resin 500 filled into the case 400. The case 400 includes an opening 410 through which the capacitor element 100 is accommodated when accommodated in the case 400, a bottom surface 420 facing the opening 410, and a first side surface 430 extending from an edge of the bottom surface 420 toward the opening 410. The first bus bar 200 forms a part of the first side surface 430 and has a first electrode terminal 210 exposed to the outside of the case 400 at the first side surface 430.

[0067] This configuration shortens the heat dissipation path from capacitor element 100 to the outside of case 400. Therefore, heat generated by capacitor element 100 can be efficiently dissipated to the outside of case 400 (Effect 1).

[0068] Furthermore, case 400 further includes a second side surface portion 440 that extends from the edge of bottom surface portion 420 toward opening 410 and faces first side surface portion 430. Second bus bar 300 forms a part of second side surface portion 440 and has second electrode terminal portion 310 that is exposed to the outside of case 400 at second side surface portion 440.

[0069] With this configuration, heat can be dissipated from two locations, the first side surface portion 430 and the second side surface portion 440, via a short heat dissipation path, so that the heat generated by the capacitor element 100 can be dissipated outside the case 400 more efficiently (Effect 2).

[0070] Furthermore, the first electrode terminal portion 210 has a first terminal 211 joined to the first electrode 110 , and the second electrode terminal portion 310 has a second terminal 311 joined to the second electrode 120 .

[0071] According to this configuration, the first electrode terminal 210, having the first terminal 211, is likely to come close to the first electrode 110, i.e., the capacitor element 100, and the second electrode terminal 310, having the second terminal 311, is likely to come close to the second electrode 120, i.e., the capacitor element 100. Therefore, heat from the capacitor element 100 is easily conducted to the first electrode terminal 210 and the second electrode terminal 310, and the heat generated by the capacitor element 100 can be more efficiently released to the outside of the case 400 (Effect 3).

[0072] Furthermore, in the first electrode terminal portion 210, a first terminal 211 to be joined to the first electrode 110 by soldering is formed by hollowing out the periphery of the first terminal 211, and a first bore hole 212 is formed around the first terminal 211. In addition, in the second electrode terminal portion 310, a second terminal 311 to be joined to the second electrode 120 by soldering is formed by hollowing out the periphery of the second terminal 311, and a second bore hole 312 is formed around the second terminal 311. The first bore hole 212 and the second bore hole 312 are closed and sealed with solder S.

[0073] According to this configuration, the first borehole 212 created to form the first terminal 211 and the second borehole 312 created to form the second terminal 311 are sealed with solder S, thereby preventing moisture contained in the air outside the case 400 from entering the inside of the case 400 through these first borehole 212 and second borehole 312 (Effect 4).

[0074] Furthermore, first bus bar 200 and second bus bar 300 are insert molded into case 400 , and thus have portions embedded in case 400 .

[0075] This configuration improves the adhesion between first bus bar 200 and second bus bar 300 and case 400, thereby improving the airtightness of case 400. This makes it more difficult for moisture contained in the air outside case 400 to penetrate into the interior of case 400 (Effect 5).

[0076] Furthermore, first bus bar 200 further includes a first relay portion 220 embedded in bottom surface portion 420 and connected to first electrode terminal portion 210, and a first connection terminal portion 230 extending from first relay portion 220 and protruding outward from bottom surface portion 420 to be connected to an external terminal. Second bus bar 300 further includes a second relay portion 320 embedded in bottom surface portion 420 and connected to second electrode terminal portion 310, and a second connection terminal portion 330 extending from second relay portion 320 and protruding outward from bottom surface portion 420 to be connected to an external terminal.

[0077] According to this configuration, the first relay portion 220 and the second relay portion 320 are passed through the inside of the bottom surface portion 420, and the first connection terminal portion 230 and the second connection terminal portion 330 are arranged to extend from the bottom surface portion 420 to the outside, so that when the capacitor element 100 is housed in the case 400 through the opening 410, the first connection terminal portion 230 and the second connection terminal portion 330 do not get in the way (Effect 6).

[0078] Furthermore, first bus bar 200 and second bus bar 300 are embedded in bottom surface portion 420 and have first overlapping portion 222 and second overlapping portion 322 that overlap each other with the resin inside bottom surface portion 420 sandwiched therebetween.

[0079] This configuration is expected to reduce the ESL (equivalent series inductance) of the film capacitor 1. Furthermore, because the resin inside the bottom surface portion 420 can be interposed between the first overlapping portion 222 and the second overlapping portion 322, unlike a configuration in which the first overlapping portion 222 and the second overlapping portion 322 overlap outside the bottom surface portion 420, it is not necessary to prepare an insulating member to be interposed between the first overlapping portion 222 and the second overlapping portion 322 separately from the case 400 (Effect 7).

[0080] Furthermore, the manufacturing method of the film capacitor 1 includes a case 400 formed from a resin material and including an opening 410, a bottom surface 420 facing the opening 410, and a first side surface 430 and a second side surface 440 extending from an edge of the bottom surface 420 toward the opening 410 and facing each other, wherein a portion of the first side surface 430 is configured by a portion of the first bus bar 200, a portion of the first bus bar 200 is exposed to the outside at the first side surface 430, and a portion of the second side surface 440 is configured by a portion of the second bus bar 300, 440, the method includes a preparation step of preparing case 400 in which a portion of second bus bar 300 is exposed to the outside, an accommodation step of accommodating capacitor element 100 having first electrode 110 on one end surface and second electrode 120 on the other end surface into case 400 through opening 410, a joining step of joining first bus bar 200 and second bus bar 300 to first electrode 110 and second electrode 120, respectively, by soldering, and a filling step of filling case 400 with filling resin 500 through opening 410 and curing filling resin 500. Here, first terminal 211 is formed in a portion of first bus bar 200 by hollowing out the periphery of first terminal 211, and first bore hole 212 is formed around first terminal 211. Furthermore, second terminal 311 is formed in a portion of second bus bar 300 by hollowing out the periphery of second terminal 311, and second bore holes 312 are formed around second terminal 311. Then, in the bonding step, first terminal 211 and second terminal 311 are bonded to first electrode 110 and second electrode 120, respectively, with solder S, and first bore holes 212 and second bore holes 312 are sealed with solder S.

[0081] This manufacturing method makes it possible to manufacture a film capacitor 1 that can efficiently release heat generated by the capacitor element 100 to the outside of the case 400. Furthermore, because the first bore holes 212 created to form the first terminals 211 and the second bore holes 312 created to form the second terminals 311 are sealed with solder S, it is possible to prevent the filling resin 500 in a liquid phase from leaking to the outside of the case 400 through the first bore holes 212 and each second bore hole 312 (Effect 8).

[0082] Furthermore, first bus bar 200 has a first outer peripheral region 213 around the periphery of first bore hole 212, from which solder S sealing first bore hole 212 protrudes. Second bus bar 300 has a second outer peripheral region 313 around the periphery of second bore hole 312, from which solder S sealing second bore hole 312 protrudes. The thicknesses of first terminal 211 and first outer peripheral region 213 are smaller than the thickness of the periphery of first outer peripheral region 213 in first bus bar 200 (first electrode terminal portion 210), and the thickness of second terminal 311 and second outer peripheral region 313 is smaller than the thickness of the periphery of second outer peripheral region 313 in second bus bar 300 (second electrode terminal portion 310).

[0083] According to this configuration, the thermal capacity of the first terminal 211, the second terminal 311, the first outer peripheral region 213, and the second outer peripheral region 313 can be reduced, so that the temperature of the molten solder S is less likely to drop, and soldering can be performed satisfactorily (Effect 9).

[0084] Second Embodiment A film capacitor 2 according to a second embodiment will be described.

[0085] In this embodiment, the film capacitor 2 corresponds to the "capacitor" in the claims. The bottom surface portion 820 corresponds to the "first surface portion" in the claims. The first side surface portion 830 corresponds to the "second surface portion" in the claims. The first electrode terminal portion 610 corresponds to the "first case component" in the claims.

[0086] However, the above description is merely intended to match the configuration of the claims with the configuration of the embodiments, and the above correspondence does not in any way limit the invention described in the claims to the configuration of the embodiments.

[0087] Fig. 14(a) is a diagram showing the film capacitor 2 as viewed from the front of the opening 810. Fig. 14(b) is a diagram showing the film capacitor 2 as viewed from the front of the bottom surface 820. Figs. 15(a) and 15(b) are cross-sectional views of the film capacitor 2 taken along lines DD' and EE' in Fig. 14(a), respectively.

[0088] In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals.

[0089] The film capacitor 2 includes three capacitor elements 100 , a first bus bar 600 , a second bus bar 700 , a case 800 , and a filling resin 500 .

[0090] The first bus bar 600 is formed by appropriately cutting out and bending a conductive material, for example, a copper plate, and has a configuration in which a first electrode terminal portion 610, a first relay portion 620, and four first connection terminal portions 630 are integrated together.

[0091] The first electrode terminal 610 has a substantially rectangular plate shape that is elongated in the Y-axis direction. Both surfaces of the first electrode terminal 610 face the Z-axis direction. Three sets of first terminals 611, first boreholes 612, and first outer peripheral regions 613 are formed in the first electrode terminal 610 and aligned in the Y-axis direction. The first terminals 611, first boreholes 612, and first outer peripheral regions 613 have configurations similar to the first terminals 211, first boreholes 212, and first outer peripheral regions 213 of the first embodiment. A plurality of holes 614 are formed in the first outer peripheral region 613. The thickness of the first terminals 611 and the first outer peripheral region 613 is smaller than the thickness of the first electrode terminal 610 around the first outer peripheral region 613.

[0092] The first bored hole 612 is a first through hole that penetrates the first electrode terminal portion 610 in the Z-axis direction, and the first outer peripheral region 613 is a peripheral portion of the first through hole. The peripheral portion of the first through hole (first outer peripheral region 613) and the first terminal 611 form a first terminal portion. The first terminal 611 is located inside the first through hole (first bored hole 612) and is connected to the peripheral portion of the first through hole. The first through hole (first bored hole 612) and the first terminal portion form a first bonding portion that is bonded to the first electrode 110 of each capacitor element 100.

[0093] The first link portion 620 has a substantially rectangular plate shape that is long in the Y-axis direction, and extends in the positive Z-axis direction from the edge of the first electrode terminal portion 610 in the negative X-axis direction. The end portion of the first link portion 620 on the positive Z-axis direction side functions as a first overlapping portion.

[0094] The four first connection terminal portions 630 have a substantially rectangular plate shape and extend in the positive Z-axis direction from the edge of the first relay portion 620 in the positive Z-axis direction. The four first connection terminal portions 630 are arranged at predetermined intervals in the Y-axis direction.

[0095] The second bus bar 700 is formed by appropriately cutting out and bending a conductive material, for example, a copper plate, and has a configuration in which a second electrode terminal portion 710, a second relay portion 720, and four second connection terminal portions 730 are integrated together.

[0096] The second electrode terminal 710 has a substantially rectangular plate shape that is long in the Y-axis direction. Both surfaces of the second electrode terminal 710 face the Z-axis direction. The second electrode terminal 710 has three sets of second terminals 711 and second boreholes 712 that are aligned in the Y-axis direction and have the same configuration as the second terminals 311 and second boreholes 312 of the first embodiment. The thickness of the second terminals 711 is smaller than the thickness of the second electrode terminal 710 around the second boreholes 712.

[0097] The second link portion 720 has a generally rectangular plate shape that is elongated in the Y-axis direction, and extends in the Z-axis positive direction from the edge of the second electrode terminal portion 710 in the X-axis negative direction. The second link portion 720 functions as a second overlapping portion.

[0098] The four second connection terminal portions 730 have a substantially rectangular plate shape and extend in the positive Z-axis direction from the edge of the second relay portion 720 in the positive Z-axis direction. The four second connection terminal portions 730 are lined up at predetermined intervals in the Y-axis direction.

[0099] The case 800 is made of a resin material, for example, a thermoplastic resin such as polyphenylene sulfide (PPS). The case 800 may also be made of a thermosetting resin such as an epoxy resin.

[0100] Case 800 has a substantially rectangular box shape and includes a square opening 810, a square bottom surface 820 facing opening 810, square first side surface 830 and second side surface 840 that extend from both edges of bottom surface 820 on the X-axis direction toward opening 810 (positive direction of the Z-axis) and face each other, and square third side surface 850 and fourth side surface 860 that extend from both edges of bottom surface 820 on the Y-axis direction toward opening 810 (positive direction of the Z-axis) and face each other. The dimension of case 800 in the Y-axis direction is greater than the dimension in the X-axis direction, and the dimensions of case 800 in the Y-axis direction and the X-axis direction are greater than the dimension in the Z-axis direction.

[0101] First bus bar 600 is insert-molded into case 800 and is integrated with case 800. That is, first bus bar 600 and second bus bar 700 have portions that are embedded in case 800.

[0102] The bottom surface portion 820 has a rectangular opening 821 that is long in the Y-axis direction. The opening 821 occupies most of the bottom surface portion 820. In other words, the bottom surface portion 820 is open except for four elongated end portions 822 on both sides in the X-axis direction and both sides in the Y-axis direction.

[0103] The opening 821 in the bottom surface portion 820 is closed by the first electrode terminal portion 610 of the first bus bar 600. That is, the first electrode terminal portion 610, as a first case component, forms a region corresponding to the opening 821 in the bottom surface portion 820, and is exposed to the outside of the case 800 at the bottom surface portion 820. Both ends in the X-axis direction and both ends in the Y-axis direction of the first electrode terminal portion 610 are embedded in four ends 822 of the bottom surface portion 820.

[0104] The first link portion 620 of the first bus bar 600 is embedded in the first side surface portion 830. Four first connection terminal portions 630 extend from the first link portion 620 and protrude from the first side surface portion 830 to the outside.

[0105] The three capacitor elements 100 are housed in the case 800 so that one end face, i.e., the first electrode 110, faces the bottom surface 820 and the other end face, i.e., the second electrode 120, faces the opening 810. The first electrode terminal 610 of the first bus bar 600, which forms part (most of) the bottom surface 820, covers the three first electrodes 110 and is close to these first electrodes 110. In addition, the second electrode terminal 710 of the second bus bar 700 covers the three second electrodes 120 and is close to these second electrodes 120.

[0106] The three first terminals 611 of the first electrode terminal portion 610 are joined to the first electrodes 110 corresponding to each first terminal 611 with solder S. Furthermore, the three first bore holes 612 of the first electrode terminal portion 610 are closed and sealed with solder S. The solder S protrudes into and covers the first outer peripheral region 613. As a result, the first outer peripheral region 613 is also joined to the first electrodes 110 with the solder S.

[0107] The three second terminals 711 of the second electrode terminal portion 710 are joined to the second electrodes 120 corresponding to the respective second terminals 711 by solder S. The three second bore holes 712 of the second electrode terminal portion 710 are not sealed with solder S.

[0108] The end (first overlapping portion) of the first relay portion 620 of the first bus bar 600 and the second relay portion (second overlapping portion) 720 of the second bus bar 700 overlap each other in the X-axis direction, sandwiching the portion of the first side surface portion 830 on the positive side of the X-axis. This is expected to reduce the ESL (equivalent series inductance) of the film capacitor 2.

[0109] Filling resin 500 is filled inside case 800, which houses three capacitor elements 100. Each capacitor element 100 and second electrode terminal portion 710 of second bus bar 700 are buried in filling resin 500. Covering each capacitor element 100 with filling resin 500 protects it from moisture and impact.

[0110] Four first connection terminals 630 and four second connection terminals 730 are arranged adjacent to each other in the Y-axis direction outside the case 800. Each of the first connection terminals 230 and each of the second connection terminals 330 is connected by welding to an external terminal corresponding to the connection terminals.

[0111] The film capacitor 2 of this embodiment is manufactured by a manufacturing method similar to the manufacturing method of the above-described film capacitor 1. However, in the housing step, the three capacitor elements 100 and the second bus bar 700 are housed in the case 800 through the opening 810. Furthermore, the second terminals 711 of the second bus bar 700 are joined to the second electrodes 120 of the three capacitor elements 100 with solder S in the joining step or before they are housed in the case 800 in the housing step.

[0112] In the film capacitor 2 of this embodiment, when it is mounted on an external device or the like, a cooling device 10 can be attached to the bottom surface 820 of the case 800, i.e., the first electrode terminal 610, via a heat dissipation sheet 11.

[0113] In the film capacitor 2, heat generated by each capacitor element 100 when current is applied is transferred to the first electrode terminal 610 and the second electrode terminal 710. Because the first electrode terminal 610 is exposed to the outside of the case 800 at the bottom surface 820, the heat transferred to the first electrode terminal 610 is immediately released to the outside of the case 800 and absorbed by the cooling device 10 via the heat dissipation sheet 11. This suppresses the temperature rise of each capacitor element 100, making the film capacitor 1 less likely to overheat.

[0114] The heat transferred to the second electrode terminal 710 is dissipated to the outside of the case 800 via the four second connection terminals 730 and the filling resin 500 .

[0115] <Effects of Second Embodiment> According to the first embodiment, the following effects are achieved.

[0116] In the film capacitor 2 , the first bus bar 600 forms part of the bottom surface 820 of the case 800 , and has a first electrode terminal 610 exposed to the outside of the case 800 at the bottom surface 820 .

[0117] This configuration shortens the heat dissipation path from capacitor element 100 to the outside of case 800. Therefore, heat generated by capacitor element 100 can be efficiently dissipated to the outside of case 800.

[0118] Furthermore, the first electrode terminal portion 610 has a first terminal 611 joined to the first electrode 110 .

[0119] According to this configuration, the first electrode terminal 610 has the first terminal 611, and therefore is likely to come into close proximity with the first electrode 110, i.e., the capacitor element 100. Therefore, heat from the capacitor element 100 is easily conducted to the first electrode terminal 610, and the heat generated by the capacitor element 100 can be dissipated to the outside of the case 800 more efficiently.

[0120] Furthermore, in the first electrode terminal portion 610, a first terminal 611 to be joined to the first electrode 110 by soldering is formed by hollowing out the periphery of the first terminal 611, and a first hollowed-out hole 612 is formed around the first terminal 611. The first hollowed-out hole 612 is then closed and sealed with solder S.

[0121] According to this configuration, the first bore hole 612 created to form the first terminal 611 is sealed with solder S, thereby preventing moisture contained in the air outside the case 800 from entering the inside of the case 800 through the first bore hole 612.

[0122] Furthermore, the first bus bar 600 has a first outer peripheral region 613 around the first hollowed hole 612, from which the solder S that has sealed the first hollowed hole 612 protrudes. The thickness of the first terminal 611 and the first outer peripheral region 613 is smaller than the thickness of the first electrode terminal portion 610 around the first outer peripheral region 613.

[0123] According to this configuration, the heat capacity of the first terminal 611 and the first outer peripheral region 613 can be reduced, so that the temperature of the molten solder S is less likely to drop, and soldering can be performed satisfactorily.

[0124] Third Embodiment A film capacitor 3 according to a third embodiment will be described.

[0125] In this embodiment, the film capacitor 3 corresponds to the "capacitor" in the claims. The bottom surface portion 920 corresponds to the "first surface portion" in the claims. The first side surface portion 930 corresponds to the "second surface portion" in the claims. The second side surface portion 940 corresponds to the "third surface portion" in the claims. The first electrode terminal portion 1010 corresponds to the "first case component" and "part of the first bus bar" in the claims. The second electrode terminal portion 1110 corresponds to the "second case component" and "part of the second bus bar" in the claims.

[0126] However, the above description is merely intended to match the configuration of the claims with the configuration of the embodiments, and the above correspondence does not in any way limit the invention described in the claims to the configuration of the embodiments.

[0127] FIG. 16 is a perspective view of the film capacitor 3 with the bottom surface 920 of the case 900 facing upward. FIG. 17 is a perspective view of the film capacitor 3 with the opening 910 of the case 900 facing upward. FIG. 18 is a perspective view of the first bus bar 1000 and the second bus bar 1100. FIG. 19(a) is a plan view of the case 900 seen from the opening 910 side, and FIG. 19(b) is a plan view of the case 900 accommodating multiple capacitor elements 100 seen from the opening 910 side. FIG. 20(a) is a cross-sectional view taken along the line D-D' in FIG. 19(a), and FIG. 20(b) is a cross-sectional view taken along the line E-E' in FIG. 19(b). Note that the solder S is omitted in FIG. 17, and the filling resin 500 is shown as transparent and partially hatched so that the capacitor elements 100 can be seen. Furthermore, the solder S is indicated by a dashed line in FIG. 20(b).

[0128] In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals.

[0129] The film capacitor 3 includes a case 900, and a first bus bar 1000 and a second bus bar 1100 integrated with the case 900. The film capacitor 3 further includes six capacitor elements 100 housed in the case 900, and a filling resin 500 filled in the case 900.

[0130] The first bus bar 1000 is formed from a conductive material such as copper, and has a configuration in which six first electrode terminal portions 1010, a first relay portion 1020, and four first connection terminal portions 1030 are integrated together.

[0131] The six first electrode terminals 1010 have a width (dimension) in the Y-axis direction (the direction in which the capacitor elements 100 are arranged) that is smaller than the width (dimension) of the capacitor elements 100 in the Y-axis direction, and are arranged at predetermined intervals in the Y-axis direction. This provides a predetermined gap G between two adjacent first electrode terminals 1010.

[0132] The six first electrode terminals 1010 include a main body 1011 having a semi-elliptical plate shape, a rectangular plate-shaped connection end 1012 located on the positive side of the main body 1011 in the Z-axis direction and narrower than the main body 1011, and a U-shaped protrusion 1013 formed on the outer periphery of the main body 1011 and protruding beyond the main body 1011. Each first electrode terminal 1010 is provided with a first bonding portion 1014 on the main body 1011 that is bonded to the first electrode 110 of each capacitor element 100. The first bonding portion 1014 has a first through hole 1015 and a first terminal 1016. The first through hole 1015 has a circular shape and penetrates the first electrode terminal 1010 in the X-axis direction. The first terminal 1016 includes a peripheral portion 1017 of the first through hole 1015 and a first terminal 1018. The peripheral edge portion 1017 has a circular ring shape, and its thickness is smaller than the thickness of the periphery of the first bonding portion 1014 in the first electrode terminal portion 1010. The first terminal 1018 has an I-shape, is located inside the first through-hole 1015, and has both ends connected to the peripheral edge portion 1017. The thickness of the first terminal 1018 is smaller than the thickness of the periphery of the first bonding portion 1014 in the first electrode terminal portion 1010.

[0133] The first relay portion 1020 relays between the first electrode terminal portion 1010 and the four first connection terminal portions 1030. The first relay portion 1020 has a rectangular plate shape that is elongated in the Y-axis direction. The connection end portion 1012 of the first electrode terminal portion 1010 is connected to the first relay portion 1020.

[0134] The four first connection terminals 1030 have a rectangular plate shape bent into an L. A circular mounting hole 1031 is formed at the tip of each first connection terminal 1030.

[0135] The second bus bar 1100 is formed from a conductive material such as copper, and has a configuration in which six second electrode terminal portions 1110, a second relay portion 1120, and four second connection terminal portions 1130 are integrated together.

[0136] The six second electrode terminals 1110 have a width (dimension) in the Y-axis direction (the direction in which the capacitor elements 100 are arranged) that is smaller than the width (dimension) of the capacitor elements 100 in the Y-axis direction, and are arranged at predetermined intervals in the Y-axis direction. This provides a predetermined gap G between two adjacent second electrode terminals 1110.

[0137] The six second electrode terminals 1110 have a configuration similar to that of the first electrode terminals 1010 and include a main body 1111, a connection end 1112, and a protrusion 1113. Each first electrode terminal 1010 has a second bonding portion 1114 on the main body 1111 that is bonded to the second electrode 120 of each capacitor element 100. The second bonding portion 1114 includes a second through hole 1115 and a second terminal 1116. The first through hole 1015 has a circular shape and penetrates the second electrode terminal 1110 in the X-axis direction. The second terminal 1116 includes a peripheral portion 1117 of the second through hole 1115 and a second terminal 1118. The peripheral portion 1117 has a circular ring shape and its thickness is smaller than the thickness of the periphery of the second bonding portion 1114 in the second electrode terminal 1110. The second terminal 1118 has an I-shape and is located inside the second through-hole 1115, with both ends connected to the peripheral edge 1117. The thickness of the second terminal 1118 is smaller than the thickness of the periphery of the second joint portion 1114 in the second electrode terminal portion 1110.

[0138] The second relay portion 1120 relays between the second electrode terminal portion 1110 and the four second connection terminal portions 1130. The second relay portion 1120 has a rectangular plate shape that is elongated in the Y-axis direction. The connection end portion 1112 of the second electrode terminal portion 1110 is connected to the second relay portion 1120.

[0139] The four second connection terminals 1130 have a rectangular plate shape bent into an L. A circular mounting hole 1131 is formed at the tip of each second connection terminal 1130.

[0140] The case 900 is made of a resin material, for example, a thermoplastic resin such as polyphenylene sulfide (PPS). The case 900 may also be made of a thermosetting resin such as an epoxy resin.

[0141] The case 900 has a substantially rectangular box shape and includes a rectangular opening 910, a rectangular bottom surface 920 facing the opening 910, a rectangular first side surface 930 and a rectangular second side surface 940 extending from both edges of the bottom surface 920 on the X-axis direction toward the opening 910 (in the negative Z-axis direction) and facing each other, and a rectangular third side surface 950 and a rectangular fourth side surface 960 extending from both edges of the bottom surface 920 on the Y-axis direction toward the opening 910 (in the negative Z-axis direction) and facing each other. The dimension of the case 900 in the Y-axis direction is greater than the dimension in the Z-axis direction, and the dimensions of the case 900 in the Y-axis direction and the Z-axis directions are greater than the dimension in the X-axis direction.

[0142] The interior of the case 900 is divided into six compartments 901 in the Y-axis direction by five partition plates 970 aligned in the Y-axis direction. The dimensions of each compartment 901 in the X-axis direction and the Y-axis direction are approximately equal to the dimensions of the capacitor element 100 in the X-axis direction and the Y-axis direction. Each partition plate 970 is approximately U-shaped, and its central portion is cut out and opened from the opening 910 side of the case 900 toward the bottom surface 920 side (see FIG. 20( a)).

[0143] First bus bar 1000 and second bus bar 1100 are integrated with case 900 by insert molding, and have portions embedded in case 900 .

[0144] Six circular openings 931 are provided in the first side surface portion 930 so as to be aligned in the Y-axis direction (the direction in which the capacitor elements 100 are aligned). Each opening 931 is located at the center of each section 901 in the Y-axis direction.

[0145] The six first electrode terminals 1010 of the first bus bar 1000 are embedded in the first side surface portion 930 so as to cover the six openings 931. As a result, the six first electrode terminals 1010 form areas corresponding to the six openings 931 in the first side surface portion 930. Furthermore, each first electrode terminal 1010 is arranged in each compartment 901.

[0146] In each first electrode terminal portion 1010, the central portion including the first joint portion 1014 in the main body portion 1011 is exposed to the outside of the case 900 through each opening 931, and almost the entire main body portion 1011 and the connection end portion 1012 are exposed to the inside of the case 900 (see Figure 20 (a)).

[0147] Each first electrode terminal 1010 has a protrusion 1013 provided on the outer periphery of the main body 1011 that is not exposed to either the outside or the inside of the case 900, and is completely embedded inside the first side surface 930 (see FIG. 20( a)). This makes it difficult for each first electrode terminal 1010 to come off from the first side surface 930 inward of the case 900.

[0148] Six circular openings 941 are provided in the second side surface portion 940 so as to be aligned in the Y-axis direction (the direction in which the capacitor elements 100 are aligned). Each opening 941 is located at the center of each section 901 in the Y-axis direction.

[0149] The six second electrode terminals 1110 of the second bus bar 1100 are embedded in the second side surface portion 940 so as to cover the six openings 941. As a result, the six second electrode terminals 1110 form areas corresponding to the six openings 941 in the second side surface portion 940. Furthermore, each second electrode terminal 1110 is disposed in one of the compartments 901.

[0150] In each second electrode terminal portion 1110, the central portion including the second joint portion 1114 in the main body portion 1111 is exposed to the outside of the case 900 through each opening 941, and almost the entire main body portion 1111 and the connection end portion 1112 are exposed to the inside of the case 900 (see Figure 20 (a)).

[0151] Each second electrode terminal 1110 has a protrusion 1113 provided on the outer periphery of the main body 1111, which is not exposed to either the outside or the inside of the case 900, and is completely embedded inside the second side surface 940 (see FIG. 20( a)). This makes it difficult for each second electrode terminal 1110 to come off from the second side surface 940 inward of the case 900.

[0152] Each partition plate 970 is present at the position of the gap G between two adjacent first electrode terminals 1010 and the position of the gap G between two adjacent second electrode terminals 1110. Therefore, each partition plate 970 tends to reinforce the portion of the first side surface portion 930 where no first electrode terminals 1010 are present and the portion of the second side surface portion 940 where no second electrode terminals 1110 are present, and the rigidity of the case 900 tends to be increased.

[0153] First relay portions 1020 of the first bus bar 1000 and second relay portions 1120 of the second bus bar 1100 are embedded in the bottom surface portion 920. Four first connection terminal portions 1030 extending from the first relay portions 1020 and four second connection terminal portions 1130 extending from the second relay portions 1120 protrude to the outside from the bottom surface portion 920. The four first connection terminal portions 1030 and the four second connection terminal portions 1130 are lined up adjacent to each other in the Y-axis direction.

[0154] The case 900 has mounting tabs 980 on the third side surface portion 950 and the fourth side surface portion 960. When the film capacitor 3 is installed in an installation portion of an external device or the like, these mounting tabs 980 are fixed to the installation portion with screws or the like.

[0155] The six capacitor elements 100 are housed in six compartments 901 within the case 400 such that the first electrodes 110 face the first side surface 930 and the second electrodes 120 face the second side surface 940. Each first electrode terminal 1010 (main body 1011 and connection end 1012) covers and is close to each first electrode 110. Each second electrode terminal 1110 (main body 1111 and connection end 1112) covers and is close to each second electrode 120. The first electrode terminal 1010 may or may not be in contact with the first electrode 110, and the second electrode terminal 1110 may or may not be in contact with the second electrode 120.

[0156] The first joint portion 1014 of each first electrode terminal portion 1010, i.e., the first terminal portion 1016, is joined to each first electrode 110 with solder S. At this time, the first through hole 1015 of the first joint portion 1014 is closed and sealed with solder S. The solder S protrudes onto a peripheral portion 1017 of the first through hole 1015, covering almost the entire peripheral portion 1017.

[0157] Similarly, the second joint portion 1114 of each second electrode terminal portion 1110, i.e., the second terminal portion 1116, is joined to each first electrode 110 with solder S. At this time, the second through hole 1115 of the second joint portion 1114 is closed and sealed with solder S. The solder S protrudes onto the peripheral portion 1117 of the second through hole 1115, covering almost the entire peripheral portion 1117.

[0158] The film capacitor 3 of this embodiment is manufactured by a manufacturing method similar to that of the film capacitor 1 described above. In this case, in the housing step, each capacitor element 100 is housed in each compartment 901 in the case 900. This prevents each capacitor element 100 from tipping over in the Y-axis direction, which is the arrangement direction of the capacitor elements 100, and also prevents each capacitor element 100 from becoming misaligned or tilted in the Y-axis direction. Furthermore, in the filling step, the liquid-phase filling resin 500 injected into the case 900 passes through the central opening of the partition plate 970, thereby facilitating flow between the two compartments 901. This reduces the likelihood of improper filling of the filling resin 500 into the case 900.

[0159] In the film capacitor 3 of this embodiment, when the case 900 is mounted on an external device or the like, a cooling device can be attached to the first side surface 930 and the second side surface 940 of the case 900. In this case, the cooling device or the heat dissipation sheet is provided with protrusions having shapes corresponding to the openings 931, 941 of the first side surface 930 and the second side surface 940, and the protrusions are inserted into the openings 931, 941 to come into contact with the first electrode terminal 1010 and the second electrode terminal 1110.

[0160] In the film capacitor 3, heat generated by each capacitor element 100 is conducted to each first electrode terminal 1010 and each second electrode terminal 1110. Because each first electrode terminal 1010 and each second electrode terminal 1110 is exposed to the outside of the case 900 at the first side surface 930 and the second side surface 940, respectively, the heat conducted to each first electrode terminal 1010 and each second electrode terminal 1110 is immediately released to the outside of the case 900 and absorbed by the cooling device via the heat dissipation sheet. This suppresses the temperature rise of each capacitor element 100, making the film capacitor 3 less likely to overheat.

[0161] In the film capacitor 3, the first joint portions 1014 and their peripheral portions of the six first electrode terminals 1010 are exposed to the outside of the case 900 through the six openings 931 in the first side surface portion 930, and the second joint portions 1114 and their peripheral portions of the six second electrode terminals 1110 are exposed to the outside of the case 900 through the six openings 941 in the second side surface portion 940. Therefore, compared with the first electrode terminals 210 and second electrode terminals 310 that make up the majority of the first side surface portion 430 and second side surface portion 440 in the film capacitor 1 of embodiment 1, the exposed areas of the multiple first electrode terminals 1010 and the multiple second electrode terminals 1110 that are exposed to the outside of the case 900 are smaller. However, because the first joint portions 1014 and the second joint portions 1114 are joined with solder S, they have high adhesion to the first electrodes 110 and second electrodes 120. Therefore, most of the heat generated by the first electrode 110 and the second electrode 120 is easily transferred to the first joint 1014 and the second joint 1114. Therefore, in the film capacitor 3, at least the first joint 1014 and the second joint 1114 are exposed to the outside of the case 900, so the heat dissipation performance is not significantly deteriorated compared to the film capacitor 1.

[0162] Furthermore, in the film capacitor 3, the main body portions 1011, 1111 and the connection ends 1012, 1112 are almost entirely exposed inside the case 900, so the exposed areas of the first electrode terminal portion 1010 and the second electrode terminal portion 1110 are larger than the exposed areas outside the case 900. This makes it possible to increase the areas of the portions of the first electrode terminal portion 1010 and the second electrode terminal portion 1110 that are close to the first electrode 110 and the second electrode 120, so that heat is more easily conducted from the first electrode 110 and the second electrode 120 to the first electrode terminal portion 1010 and the second electrode terminal portion 1110.

[0163] <Effects of Third Embodiment> As described above, according to the third embodiment, it is possible to achieve the same effects as effects 1 to 6 and effect 9 of the first embodiment.

[0164] Furthermore, the film capacitor 3 includes a plurality of capacitor elements 100, and the first bus bar 1000 and the second bus bar 1100 are connected to the first electrodes 110 and the second electrodes 120 of the plurality of capacitor elements 100, respectively. The interior of the case 900 is divided into a plurality of compartments 901 by partition plates 970, and each capacitor element 100 is housed in each compartment 901.

[0165] This configuration can prevent each capacitor element 100 from becoming misaligned, and can keep within an appropriate range the joining position of first bus bar 1000 and second bus bar 1100 with solder S for each capacitor element 100. Furthermore, it can prevent each capacitor element 100 from falling over when accommodated in case 900, or from being accommodated in case 900 in an inclined state.

[0166] Furthermore, the first bus bar 1000 forms part of the first side surface portion 930 and has a plurality of first electrode terminal portions 1010 exposed to the outside of the case 900 at the first side surface portion 930, and each first electrode terminal portion 1010 is arranged in each compartment 901 with a gap G between adjacent first electrode terminal portions 1010.

[0167] With this configuration, the area of ​​the first bus bar 1000 can be made smaller than when the first bus bar 1000 has one first electrode terminal configured to fill the gap G between the multiple first electrode terminals 1010, as shown by the dashed line in Fig. 18. This makes it easier to achieve flatness for the first bus bar 1000. Furthermore, interfacial peeling between the first bus bar 1000 and the filling resin 500 is also less likely to occur.

[0168] Furthermore, the multiple first electrode terminal portions 1010 have multiple first joint portions 1014 that join to the first electrodes 110 of the multiple capacitor elements 100, and at least multiple first joint portions 1014 are exposed to the outside of the case 900.

[0169] According to this configuration, the first joint 1014, to which heat generated by the first electrode 110 of the capacitor element 100 is easily transmitted, is exposed to the outside of the case 900, and therefore, even if the area of ​​the part of the first bus bar 1000 that contributes to heat dissipation is reduced by having a configuration with multiple first electrode terminal portions 1010, a decrease in heat dissipation performance can be suppressed.

[0170] Furthermore, the second bus bar 1100 forms part of the second side surface portion 940 and has a plurality of second electrode terminal portions 1110 exposed to the outside of the case 900 at the second side surface portion 940, and each second electrode terminal portion 1110 is arranged in each compartment 901 with a gap G between adjacent second electrode terminal portions 1110.

[0171] With this configuration, the area of ​​second bus bar 1100 can be made smaller than when second bus bar 1100 has one second electrode terminal configured to fill the gap G between multiple second electrode terminals 1110, as shown by the dashed line in Fig. 18. This makes it easier to achieve flatness of second bus bar 1100. Furthermore, interfacial peeling between second bus bar 1100 and filling resin 500 is less likely to occur.

[0172] Furthermore, the multiple second electrode terminal portions 1110 have multiple second joint portions 1114 that join to the second electrodes 120 of the multiple capacitor elements 100, and at least multiple second joint portions 1114 are exposed to the outside of the case 900.

[0173] According to this configuration, the second joint 1114, to which heat generated by the second electrode 120 of the capacitor element 100 is easily transmitted, is exposed to the outside of the case 900, and therefore, even if the area of ​​the part of the second bus bar 1100 that contributes to heat dissipation is reduced by having a configuration with multiple second electrode terminal portions 1110, a decrease in heat dissipation performance can be suppressed.

[0174] <Modifications> Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications to the application examples of the present invention are possible in addition to the above-described embodiments.

[0175] For example, in the first embodiment, the first side surface portion 430 and the second side surface portion 440 of the case 400 have second ends 433, 443 that connect the ends of the two first ends 432, 442. However, as shown in Fig. 21(a) , the first side surface portion 430 and the second side surface portion 440 do not have to have the second ends 433, 443. However, by connecting the ends of the two first ends 432, 442 with the second ends 433, 443, the opening 410 side of the case 400 is prevented from deforming so as to open in the Y-axis direction.

[0176] Furthermore, in the first embodiment, the first electrode terminal 210 of the first bus bar 200 closes the opening 431 of the first side surface 430 of the case 400, thereby constituting a part of the first side surface 430, and the second electrode terminal 310 of the second bus bar 300 closes the opening 441 of the second side surface 440 of the case 400, thereby constituting a part of the second side surface 440. However, as shown in FIG. 21( b ), the first electrode terminal 210 may constitute the entire first side surface 430, or as shown in FIG. 21( c ), the second electrode terminal 310 may constitute the entire second side surface 440. In this case, both ends of the first electrode terminal 210 and the second electrode terminal 310 in the Y-axis direction may be fixed to both ends of the third side surface 450 and the fourth side surface 460 in the X-axis direction with an adhesive or the like. Similarly, in the second embodiment, the first electrode terminal portion 610 of the first bus bar 600 may form the entire bottom surface portion 820 of the case 800 .

[0177] Furthermore, the configurations of the first terminal 211, the first borehole 212, and the first outer peripheral region 213 of the first electrode terminal portion 210 and the configurations of the second terminal 311, the second borehole 312, and the second outer peripheral region 313 of the second electrode terminal portion 310 are not limited to those of the first embodiment. For example, as shown in FIG. 22( a), the first terminal 211 may have a shape that does not completely divide the circular first borehole 212. Similarly, as shown in FIG. 22( b), the second terminal 311 may have a shape that does not completely divide the circular second borehole 312. Furthermore, the first borehole 212 and the second borehole 312 may have a substantially rectangular shape instead of a circular shape, and the first outer peripheral region 213 and the second outer peripheral region 313 may have a substantially rectangular annular shape instead of a circular annular shape. Furthermore, first outer peripheral region 213 and second outer peripheral region 313 do not have to have holes 214, 314. Furthermore, the configurations of first terminal 611, first bore hole 612, and first outer peripheral region 613 of first bus bar 600 in the second embodiment can also be changed in the same manner as above.

[0178] Furthermore, in the first embodiment, the thickness of the first terminal 211 and the first outer peripheral region 213 in the first bus bar 200 is smaller than the thickness of the periphery of the first outer peripheral region 213 in the first electrode terminal portion 210, and the thickness of the second terminal 311 and the second outer peripheral region 313 in the second bus bar 300 is smaller than the thickness of the periphery of the second outer peripheral region 313 in the second electrode terminal portion 310. However, for example, the thickness of the first terminal 211 and the first outer peripheral region 213 in the first bus bar 200 may be the same as the thickness of the periphery of the first outer peripheral region 213 in the first electrode terminal portion 210, and the thickness of the second terminal 311 and the second outer peripheral region 313 in the second bus bar 300 may be the same as the thickness of the periphery of the second outer peripheral region 313 in the second electrode terminal portion 310. Similarly, in the above-mentioned second embodiment, for example, the thickness of the first terminal 611 and the first outer peripheral region 613 of the first bus bar 600 may be the same as the thickness around the first outer peripheral region 613 in the first electrode terminal portion 610, and the thickness of the second terminal 711 of the second bus bar 700 may be the same as the thickness around the second bore hole 712 in the second electrode terminal portion 710.

[0179] Furthermore, in the first embodiment, a part, but not all, of the first outer peripheral region 213 may be included in the first terminal portion of the first joint, and a part, but not all, of the second outer peripheral region 313 may be included in the second terminal portion of the second joint. Similarly, in the second embodiment, a part, but not all, of the first outer peripheral region 613 may be included in the first terminal portion of the first joint.

[0180] Furthermore, in the third embodiment, the configurations of the first bonding portion 1014 of the first electrode terminal 1010 and the second bonding portion 1114 of the second electrode terminal 1110 can be modified as appropriate. For example, the first bonding portion 1014 and the second bonding portion 1114 may have the first terminal 1018 and the second terminal 1118 having the shapes shown in FIGS. 23( a) to 23(d). Furthermore, as shown in FIG. 23(e), the first bonding portion 1014 and the second bonding portion 1114 may not have the first terminal 1018 and the second terminal 1118. That is, in the example of FIG. 23(e), the first terminal 1016 and the second terminal 1116 are formed only by the peripheral portion 1017 of the first through hole 1015 and the peripheral portion 1117 of the second through hole 1115. Furthermore, in the first bonding portion 1014 and the second bonding portion 1114, the thickness of the peripheral portion 1017 of the first through hole 1015 may be the same as the thickness of the periphery of the first bonding portion 1014, and the thickness of the peripheral portion 1117 of the second through hole 1115 may be the same as the thickness of the periphery of the second bonding portion 1114. Furthermore, the first bonding portion 1014 (first terminal portion 1016) may protrude toward the first electrode 110 of the capacitor element 100, and the second bonding portion 1114 (second terminal portion 1116) may protrude toward the second electrode 120 of the capacitor element 100. Furthermore, in the first bonding portion 1014 and the second bonding portion 1114, the first through hole 1015 and the second through hole 1115 may be formed in a shape other than a circle, such as a square shape. Furthermore, the peripheral portion 1017 of the first through hole 1015 and the A peripheral portion 1117 of the second through hole 1115 may be provided with holes similar to the holes 214, 314 of the first outer peripheral region 213 and the second outer peripheral region 313 of the above-described first embodiment. Furthermore, in the first bonding portion 1014, a portion, but not all, of the peripheral portion 1017 of the first through hole 1015 may be included in the first terminal portion 1016, and in the second bonding portion 1114, a portion, but not all, of the peripheral portion 1117 of the second through hole 1115 may be included in the second terminal portion 1116.

[0181] The shapes shown in Figures 23(b) to (d) may be applied to the first terminals 211, 611 of the first electrode terminal portions 210, 610 and the second terminals 311, 711 of the second electrode terminal portions 310, 710 in the first and second embodiments.

[0182] Furthermore, in the above-described third embodiment, the multiple openings 931 in the first side surface portion 930 of the case 900 do not have to be circular and sized so that the central portion, including the first joint portion 1014, of the main body portion 1011 of the first electrode terminal portion 1010 is exposed outside the case 900. For example, the multiple openings 931 may be sized and shaped so that almost the entire main body portion 1011 is exposed outside the case 900, or so that only the first joint portion 1014 provided on the main body portion 1011 is exposed outside the case 900. Similarly, the multiple openings 941 in the second side surface portion 940 may be sized and shaped so that almost the entire main body portion 1111 of the second electrode terminal portion 1110 is exposed outside the case 900, or so that only the second joint portion 1114 provided on the main body portion 1111 is exposed outside the case 900.

[0183] Furthermore, in the above-mentioned third embodiment, the partition plate 970 of the case 900 may have any shape as long as it can divide the case 900 into a plurality of compartments 901, and may, for example, be a square plate with no opening in the center.

[0184] Furthermore, in the above-described second embodiment, the first bus bar 600 may include a plurality of first electrode terminal portions having a configuration similar to the plurality of first electrode terminal portions 1010 of the first bus bar 1000 of the above-described third embodiment, and the bottom surface portion 820 of the case 800 may have a configuration similar to the first side surface portion 930 of the case 900 of the above-described third embodiment, i.e., a configuration having a plurality of openings.

[0185] Furthermore, in the first embodiment, the first electrode terminal 210 of the first bus bar 200, which is joined to the first electrode 110 of the capacitor element 100, constitutes a part of the first side surface 430 of the case 400 as a first case constituent part, and the second electrode terminal 310 of the second bus bar 300, which is joined to the second electrode 120 of the capacitor element 100, constitutes a part of the second side surface 440 of the case 400 as a second case constituent part. However, for example, the first relay portion 220 of the first bus bar 200 may constitute a part or all of the first side surface 430, and the second relay portion 320 of the second bus bar 300 may constitute a part or all of the second side surface 440. Similarly, in the second embodiment, for example, the first relay portion 620 of the first bus bar 600 may constitute a part or all of the bottom surface 820 of the case 800.

[0186] Furthermore, in the above-described first embodiment, the first bus bar 200 and the second bus bar 300 may have any configuration as long as a portion thereof can form part or all of the first side surface portion 430 and the second side surface portion 440 of the case 400. Similarly, in the above-described second embodiment, the first bus bar 600 may have any configuration as long as a portion thereof can form part or all of the bottom surface portion 820 of the case 800. Furthermore, in the above-described third embodiment, the plurality of first electrode terminals 1010 of the first bus bar 1000 and the plurality of second electrode terminals 1110 of the second bus bar 1100 may have any configuration as long as they can form part of the first side surface portion 930 and the second side surface portion 940 of the case 900.

[0187] Furthermore, in the first embodiment, the first electrode terminals 210 of the first bus bar 200 are joined to the first electrodes 110 of each capacitor element 100 by soldering, and the second electrode terminals 310 of the second bus bar 300 are joined to the second electrodes 120 of each capacitor element 100 by soldering. However, the first electrode terminals 210 and the second electrode terminals 310 may be joined to the first electrodes 110 and the second electrodes 120 by a joining method other than soldering, for example, welding such as spot welding or adhesion using a conductive adhesive. In this case, the portions of the first electrode terminals 210 joined to the first electrodes 110 (for example, welding points) become first joints, and the portions of the second electrode terminals 310 joined to the second electrodes 120 (for example, welding points) become second joints. Similarly, in the above-mentioned second and third embodiments, the first electrode terminal portions 610, 1010 of the first bus bars 600, 1000 and the second electrode terminal portions 710, 1110 of the second bus bars 700, 1100 may be joined to the first electrode 110 and the second electrode 120, respectively, by a joining method other than soldering, for example, by welding such as spot welding.

[0188] Furthermore, in the above-mentioned embodiment 1, a configuration may be adopted in which a portion of the second bus bar 300 (second electrode terminal portion 310) does not constitute a portion of the second side surface portion 440 of the case 400, and is not exposed outside the case 400 at the second side surface portion 440.

[0189] Furthermore, in the first embodiment, the first bus bar 200 and the second bus bar 300 are integrated with the case 400 by insert molding. However, the first bus bar 200 and the second bus bar 300 may be integrated with the case 400 by means other than insert molding, for example, by bonding with an adhesive. Similarly, in the second embodiment, the first bus bar 600 may be integrated with the case 800 by means other than insert molding. Similarly, in the third embodiment, the first bus bar 1000 and the second bus bar 1100 may be integrated with the case 900 by means other than insert molding.

[0190] Furthermore, in the first embodiment, one or more grooves extending in the Z-axis direction or the Y-axis direction may be provided on a surface of the first electrode terminal portion 210 of the first bus bar 200 facing the first electrode 110 of the capacitor element 100 and on a surface of the second electrode terminal portion 310 of the second bus bar 300 facing the second electrode 120 of the capacitor element 100. The filling resin 500 enters the grooves, thereby increasing the adhesive strength between the filling resin 500 and the first electrode terminal portion 210 and the second electrode terminal portion 310. Similarly, in the second embodiment, one or more grooves extending in the X-axis direction or the Y-axis direction may be provided on a surface of the first electrode terminal portion 610 of the first bus bar 600 facing the first electrode 110 of the capacitor element 100.

[0191] Furthermore, the shapes of the cases 400, 800, and 900 are not limited to those of the first, second, and third embodiments, and may be different from those of the first, second, and third embodiments.

[0192] Furthermore, in the first and second embodiments, the film capacitor 1 includes three capacitor elements 100. However, the number of capacitor elements 100 can be changed as appropriate, including a single capacitor element. The number of capacitor elements 100 in the film capacitor 3 of the third embodiment is also not limited to six and can be changed as appropriate. In this case, the number of first electrode terminal portions 1010 of the first bus bar 1000 and the number of second electrode terminal portions 1110 of the second bus bar 1100 are changed according to the number of capacitor elements 100. Furthermore, the number of first connection terminal portions 230, 630, 1030 of the first bus bar 200, 600, 1000 and the number of second connection terminal portions 330, 730, 1130 of the second bus bar 300, 700, 1100 in the first, second, and third embodiments is also not limited to four and can be changed as appropriate.

[0193] Furthermore, in the above-mentioned embodiments 1, 2, and 3, capacitor element 100 is formed by stacking two metallized films in which aluminum is vapor-deposited on a dielectric film, and then rolling or laminating the stacked metallized films. However, capacitor element 100 may also be formed by stacking a metallized film in which aluminum is vapor-deposited on both sides of a dielectric film and an insulating film, and then rolling or laminating the resulting film.

[0194] Furthermore, in the above-described first and second embodiments, the film capacitors 1 and 2 are given as examples of the capacitor of the present invention. However, the present invention can also be applied to capacitors other than the film capacitors 1 and 2.

[0195] In addition, the embodiments of the present invention can be modified in various ways as appropriate within the scope of the technical ideas set forth in the claims.

[0196] The present invention is useful for capacitors used in various electronic devices, electrical devices, industrial devices, vehicle electrical equipment, and the like.

[0197] REFERENCE SIGNS LIST 1 Film capacitor (capacitor) 2 Film capacitor (capacitor) 3 Film capacitor (capacitor) 10 Cooling device 100 Capacitor element 110 First electrode 120 Second electrode 200 First bus bar 210 First electrode terminal portion (first case constituent portion) 211 First terminal (first terminal portion, first joint portion) 212 First bore hole (first through hole, first joint portion) 213 First outer peripheral region (periphery of first through hole, first terminal portion, first joint portion) 220 First relay portion 222 First overlap portion 230 First connection terminal portion 300 Second bus bar 310 Second electrode terminal portion (second case constituent portion) 311 Second terminal (second terminal portion, second joint portion) 312 Second bore hole (second through hole, second joint portion) 313 Second outer peripheral region (periphery of second through hole, second terminal portion, second joint portion) 320 Second relay portion 322 Second overlapping portion 330 Second connection terminal portion 400 Case 410 Opening 420 Bottom surface portion (first surface portion) 430 First side surface portion (second surface portion) 440 Second side surface portion (third surface portion) 500 Filled resin 600 First bus bar 610 First electrode terminal portion (first case component) 611 First terminal (first terminal portion, first joint portion) 612 First borehole (first through hole, first joint portion) 613 First outer peripheral region (periphery of first through hole, first terminal portion, first joint portion) 800 Case 810 Opening 820 Bottom surface portion (first surface portion) 830 First side surface portion (second surface portion) 900 Case 910 Opening 920 Bottom surface (first surface) 930 First side surface (second surface) 940 Second side surface (third surface) 1000 First bus bar 1010 First electrode terminal (first case component) 1014 First joint 1015 First through hole 1016 First terminal 1017 Periphery of first through hole 1018 First terminal 1020 First relay portion 1030 First connection terminal 1100 Second bus bar 1110 Second electrode terminal (second case component) 1114 Second joint 1115 Second through hole 1116 Second terminal 1117 Periphery of second through hole 1118 Second terminal 1120 Second relay portion 1130 Second connection terminal G Gap S solder

Claims

1. A capacitor comprising: a capacitor element having a first electrode on one end face and a second electrode on the other end face; a first bus bar and a second bus bar connected to the first electrode and the second electrode, respectively; a case formed of a resin material and accommodating the capacitor element; and a filled resin filled into the case, wherein the case includes an opening, a first surface portion facing the opening, and a second surface portion extending from an edge of the first surface portion towards the opening side, and at least the first bus bar has a first case component portion that constitutes at least a part of one of the first and second surfaces, and is exposed to the outside of the case at the one surface portion.

2. A capacitor as claimed in claim 1, characterized in that the case further includes a third surface portion extending from an edge of the first surface portion towards the opening and facing the second surface portion, the first case component portion constituting at least a part of the second surface portion, and the second bus bar has a second case component portion constituting at least a part of the third surface portion and exposed to the outside of the case at the third surface portion.

3. A capacitor according to claim 2, characterized in that the first case component has a first joint portion joined to the first electrode, and the second case component has a second joint portion joined to the second electrode.

4. A capacitor as claimed in claim 3, characterized in that the first joint portion has a first through hole and a first terminal portion including at least a portion of the periphery of the first through hole, the second joint portion has a second through hole and a second terminal portion including at least a portion of the periphery of the second through hole, and the first through hole and the second through hole are filled with solder.

5. A capacitor as claimed in claim 4, characterized in that the thickness of the peripheral edge of the first through hole is smaller than the thickness of the periphery of the first joint of the first bus bar, the thickness of the peripheral edge of the second through hole is smaller than the thickness of the periphery of the second joint of the second bus bar, and the solder protrudes onto the peripheral edges of the first through hole and the peripheral edges of the second through hole.

6. A capacitor according to any one of claims 2 to 5, wherein the first bus bar and the second bus bar have portions embedded in the case.

7. A capacitor as claimed in claim 6, wherein the first bus bar further comprises: a first relay portion embedded in the first surface portion and connected to a first case component portion; and a first connection terminal portion extending from the first relay portion, protruding from the first surface portion to the outside, and to which an external terminal is connected; and the second bus bar further comprises: a second relay portion embedded in the first surface portion and connected to a second case component portion; and a second connection terminal portion extending from the second relay portion, protruding from the first surface portion to the outside, and to which an external terminal is connected.

8. A capacitor as claimed in claim 7, wherein the first bus bar and the second bus bar are embedded in the first surface portion, respectively, and have a first overlapping portion and a second overlapping portion that overlap each other with the resin inside the first surface portion sandwiched therebetween.

9. The capacitor according to claim 1, wherein the first case component constitutes at least a part of the first surface portion.

10. A capacitor according to claim 9, wherein the first case component has a first joint portion that is joined to the first electrode.

11. A capacitor according to claim 10, wherein the first joint portion has a first through hole and a first terminal portion including at least a portion of the periphery of the first through hole, and the first through hole is filled with solder.

12. A capacitor as claimed in claim 11, characterized in that the thickness of the peripheral portion of the first through hole is smaller than the thickness of the periphery of the first joint portion of the first bus bar, and the solder protrudes above the peripheral portion of the first through hole.

13. A capacitor according to any one of claims 9 to 12, wherein the first bus bar has a portion embedded in the case.

14. A capacitor according to claim 1, comprising a plurality of capacitor elements, and wherein the first bus bar and the second bus bar are connected to the first electrodes and the second electrodes of the plurality of capacitor elements, respectively.

15. A capacitor according to claim 14, wherein the inside of the case is divided into a plurality of compartments by partition plates, and each of the capacitor elements is housed in a respective one of the compartments.

16. A capacitor according to claim 15, characterized in that the first bus bar has a plurality of the first case components, each of the first case components being arranged in each of the sections with a gap between adjacent first case components.

17. A capacitor as claimed in claim 16, characterized in that the plurality of first case components have a plurality of first joints which join to the first electrodes of the plurality of capacitor elements, and at least the plurality of first joints are exposed to the outside of the case.

18. A capacitor as claimed in claim 16 or 17, characterized in that the case further includes a third surface portion extending from an edge of the first surface portion towards the opening and facing the second surface portion, the plurality of first case components constituting a part of the second surface portion, the second bus bar having a plurality of second case components constituting a part of the third surface portion and exposed to the outside of the case at the third surface portion, and each of the second case components being arranged in each of the compartments with a gap between adjacent second case components.

19. A capacitor as claimed in claim 18, characterized in that the second case components have a plurality of second joints which join to the second electrodes of the capacitor elements, and at least the second joints are exposed to the outside of the case.

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