Capacitor

Abstract

This film capacitor is provided with: a capacitor element; a bus bar which is connected to an electrode of the capacitor element; a case in which the capacitor element is contained; a filling resin with which the case is filled; a through hole which is provided to the case; a connection terminal part which is provided to the bus bar and is led out from the through hole to the outside, said connection terminal part being able to be connected to an external terminal; and an annular sealing member which is interposed between the outer surface of the connection terminal part and the inner wall surface of the through hole. Meanwhile, the sealing member has a deformable annular fin part on the outer surface thereof. The outer diameter of the sealing member including the fin part is larger than the diameter of the through hole; and the fin part is deformed so as to come into contact with the inner wall surface of the through hole.

Description

[Technical field]

[0001] The present invention relates to a capacitor. [Background technology]

[0002] Patent Document 1 describes a resin-sealed electrical component in which an electrical element such as a capacitor element is housed in a case, terminals for external connection connected to the electrical element are led out through the side of the case, and the case is filled with a filling resin such as epoxy resin. The filling resin is filled in a molten state into the case, and hardens inside the case after filling.

[0003] In the resin-sealed electrical component of Patent Document 1, there is a risk that the molten filling resin will leak out from a minute gap between the terminal and the through hole through which the terminal penetrates. Therefore, in this resin-sealed electrical component, a pair of first protrusions extending in the vertical direction is formed on both the left and right sides of the through hole on the side surface of the case (case side wall member), and a first resin receiving portion is formed along the lower end of the through hole so as to connect both lower ends of the pair of first protrusions. When the gap closing resin is injected from near the contact portion between the upper surface of the terminal inside the case and the inner peripheral surface of the through hole, the injected gap closing resin penetrates into the minute gap between the terminal and the inner peripheral surface of the through hole by capillary action, and the gap is blocked by the gap closing resin. After the gap closing resin hardens, the filling resin is filled into the case. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-093057 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the manufacture of the resin-sealed electrical component of Patent Document 1, a step of injecting a gap closing resin into the case and raising the temperature of the injected gap closing resin to harden it is required before the step of injecting a filling resin into the case and raising the temperature of the injected filling resin to harden it. This increases the number of steps and can make manufacturing difficult.

[0006] In view of the above problems, an object of the present invention is to provide a capacitor that can easily prevent resin leakage from through holes in a case through which the connection terminal portions of a bus bar pass. [Means for solving the problem]

[0007] A capacitor according to a first aspect of the present invention includes a capacitor element, a bus bar connected to an electrode of the capacitor element and including a connection terminal portion connectable to an external terminal, a case that houses the capacitor element and has a through hole that leads out the connection terminal portion to the outside, a filling resin that fills the case, and an annular sealing member that is inserted into the through hole and is interposed between an outer surface of the connection terminal portion and an inner wall surface of the through hole. Here, the sealing member has a deformable annular first protrusion on its outer surface. The outer diameter of the sealing member including the first protrusion is larger than the diameter of the through hole, and the first protrusion deforms so as to fall in a direction opposite to the insertion direction when the sealing member is inserted into the through hole, thereby abutting against the inner wall surface of the through hole, and the surface facing the insertion direction is inclined. Effect of the Invention

[0008] According to the present invention, it is possible to easily prevent resin leakage from the through hole of the case through which the connection terminal portion of the bus bar passes.

[0009] The effects and significance of the present invention will become clearer from the following description of the embodiment. However, the embodiment shown below is merely an example of how the present invention can be put into practice, and the present invention is not limited to the embodiment described below. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1(a) is a perspective view of a film capacitor according to an embodiment, as viewed from above and at the front, and FIG. 1(b) is a perspective view of the film capacitor according to an embodiment, as viewed from below and at the front. [Diagram 2] FIG. 2(a) is a perspective view of a capacitor element unit according to the embodiment as viewed from above the front, and FIG. 2(b) is a perspective view of a capacitor element unit according to the embodiment as viewed from above the rear. [Diagram 3] FIG. 3(a) is a perspective view of a first bus bar according to an embodiment, as viewed from below and in front, and FIG. 3(b) is a partial side cross-sectional view of the first bus bar showing the periphery of a first protrusion portion according to an embodiment. [Figure 4] FIG. 4(a) is a perspective view of a second bus bar according to an embodiment, as viewed from below and in front, and FIG. 4(b) is a partial side cross-sectional view of the second bus bar showing the periphery of a second protrusion portion according to an embodiment. [Diagram 5] FIG. 5(a) is a perspective view of the case according to the embodiment as viewed from above the front, and FIG. 5(b) is a perspective view of the case according to the embodiment as viewed from above the rear. [Figure 6] FIG. 6(a) is an oblique view of the right side portion of the case as viewed from below and the front according to the embodiment, and FIG. 6(b) is a partial front cross-sectional view of the case showing the vicinity of the first through hole and the second through hole according to the embodiment. [Figure 7] 7(a) and (b) are respectively a perspective view and a plan view of a sealing member according to an embodiment, and FIG. 7(c) is a cross-sectional view taken along line AA' of FIG. 7(b). [Figure 8] FIG. 8(a) is a side cross-sectional view of a film capacitor according to an embodiment before it is filled with a filling resin, and FIG. 8(b) is a plan view of the center of the film capacitor according to an embodiment before it is filled with a filling resin. [Figure 9] FIG. 9 is a cross-sectional view of a main part of a film capacitor according to an embodiment, illustrating the periphery of a first through hole before being filled with a filling resin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A film capacitor 1, which is one embodiment of a capacitor of the present invention, will be described below with reference to the drawings. For convenience, the front-rear, left-right, and up-down directions are indicated in each drawing as appropriate. Note that the directions shown in the drawings indicate only relative directions of the film capacitor 1, and do not indicate absolute directions. For convenience of explanation, some components may be given names that correspond to the directions shown in the drawings, such as "bottom portion" and "front side portion."

[0012] In this embodiment, the film capacitor 1 corresponds to a "capacitor" as described in the claims. The first through hole 240 and the second through hole 250 correspond to a "through hole" as described in the claims. The fin portion 410 corresponds to a "first protrusion" as described in the claims. The flange portion 420 corresponds to a "blocking portion" as described in the claims. The rib 430 corresponds to a "second protrusion" as described in the claims. The first electrode 510 and the second electrode 520 correspond to an "electrode" as described in the claims. The first bus bar 600 and the second bus bar 700 correspond to a "bus bar" as described in the claims. The first lower connection terminal portion 650 and the second lower connection terminal portion 750 correspond to a "connection terminal portion" as described in the claims.

[0013] However, the above description is intended merely 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.

[0014] FIG. 1(a) is a perspective view of the film capacitor 1 as viewed from above the front, and FIG. 1(b) is a perspective view of the film capacitor 1 as viewed from below the front.

[0015] As shown in FIGS. 1(a) and (b), the film capacitor 1 includes a capacitor element unit 100, a case 200 in which the capacitor element unit 100 is housed, a filling resin 300 filled in the case 200, and two sealing members 400.

[0016] Filling resin 300 is a thermosetting resin such as epoxy resin, which is injected in a liquid state into case 200 housing capacitor element unit 100, and then hardens by heating the inside of case 200. Most of capacitor element unit 100 buried in filling resin 300 is protected from moisture and impact.

[0017] The three first upper connection terminals 630 and the three second upper connection terminals 730 in the capacitor element unit 100 are led out from the opening 200a on the upper surface of the case 200 to the outside. The first upper connection terminals 630 and the second upper connection terminals 730 are arranged side by side in the left-right direction. The first lower connection terminals 650 and the second lower connection terminals 750 are led out through the first through holes 240 and the second through holes 250 provided in the bottom surface portion 201 of the case 200 to the outside. Sealing members 400 are respectively interposed between the outer surface of the first lower connection terminals 650 and the inner wall surface of the first through holes 240 and between the outer surface of the second lower connection terminals 750 and the inner wall surface of the second through holes 250.

[0018] Fig. 2(a) is a perspective view of capacitor element unit 100 seen from above the front, and Fig. 2(b) is a perspective view of capacitor element unit 100 seen from above the rear. Fig. 3(a) is a perspective view of first bus bar 600 seen from below the front, and Fig. 3(b) is a partial cross-sectional side view of first bus bar 600 showing the periphery of first protrusion 615. Fig. 4(a) is a perspective view of second bus bar 700 seen from below the front, and Fig. 4(b) is a partial cross-sectional side view of second bus bar 700 showing the periphery of second protrusion 715.

[0019] 2 to 4(b), the capacitor element unit 100 includes three capacitor elements 500, a first bus bar 600, a second bus bar 700, and an insulating plate 800.

[0020] Capacitor element 500 is formed by stacking two metallized films, each having aluminum vapor-deposited on a dielectric film, rolling or laminating the stacked metallized films, and pressing them into a flat shape. Capacitor element 500 has a first electrode 510 formed on one end face by spraying a metal such as zinc, and a second electrode 520 formed on the other end face by spraying a metal such as zinc. The three capacitor elements 500 are arranged so that their peripheral surfaces face each other, and in this state, a first bus bar 600 and a second bus bar 700 are connected to these capacitor elements 500.

[0021] Although capacitor element 500 of the present embodiment is formed of a metallized film in which aluminum is deposited on a dielectric film, it may also be formed of a metallized film in which other metals such as zinc, magnesium, etc. Alternatively, capacitor element 500 may be formed of a metallized film in which a plurality of these metals are deposited, or a metallized film in which an alloy of these metals is deposited.

[0022] The first bus bar 600 is formed of a conductive material, for example, a copper plate, and includes a first electrode terminal portion 610, a first upper relay portion 620, three first upper connection terminal portions 630, a first lower relay portion 640, and a first lower connection terminal portion 650. The first bus bar 600 is formed, for example, by appropriately cutting out and bending a single copper plate, and the first electrode terminal portion 610, the first upper relay portion 620, the first upper connection terminal portion 630, the first lower relay portion 640, and the first lower connection terminal portion 650 are integrated together.

[0023] The first electrode terminal portion 610 has a substantially rectangular plate shape and covers the first electrodes 510 of the capacitor elements 500. The first electrode terminal portion 610 has a substantially L-shaped cutout portion 611 formed at the left end portion, a substantially rectangular opening portion 612 formed at the center portion, and a substantially U-shaped cutout portion 613 formed at the right end portion. A pair of electrode pins 614 is formed at the upper edges of the left and right cutout portions 611, 613 and the opening portion 612. Each pair of electrode pins 614 is joined to the first electrodes 510 of the corresponding capacitor elements 500 by a joining method such as soldering. In this way, the first bus bar 600 is electrically connected to the capacitor elements 500.

[0024] A plurality of first protrusions 615 (four in this embodiment) are formed on the upper part of the first electrode terminal 610 so as to be aligned in the left-right direction and protrude forward. As shown in Fig. 3(b), each first protrusion 615 has a substantially flat truncated cone shape, with a tip 615a formed as a circular flat surface and a peripheral surface 615b having a taper. In addition, two circular holes 616 are formed on the lower part of the first electrode terminal 610.

[0025] The first upper relay portion 620 relays between the first electrode terminal portion 610 and the three first upper connection terminal portions 630. The first upper relay portion 620 extends slightly rearward from the upper edge of the first electrode terminal portion 610 and then extends slightly upward. Two oval holes 621 are formed in the first upper relay portion 620 so as to be aligned in the left-right direction.

[0026] The three first upper connection terminal parts 630 are formed at a predetermined interval on the upper edge part of the first upper relay part 620. Each first upper connection terminal part 630 extends upward from the upper end edge of the first upper relay part 620, with a wide base end and both corners of the tip part having a large R. Each first upper connection terminal part 630 has a circular mounting hole 631 formed therein.

[0027] The first lower relay portion 640 relays between the first electrode terminal portion 610 and the first lower connection terminal portion 650. The first lower relay portion 640 extends rearward from the lower edge of the first electrode terminal portion 610. The first lower relay portion 640 includes a connection portion 641 that extends rearward at its right end portion with the same width as the first lower connection terminal portion 650 and is connected to the first lower connection terminal portion 650.

[0028] The first lower connection terminal portion 650 extends downward from the tip of the connection portion 641 of the first lower relay portion 640, and has a substantially rectangular plate shape. The first lower connection terminal portion 650 has a circular mounting hole 651 formed therein.

[0029] The second bus bar 700 is formed of a conductive material, for example, a copper plate, and includes a second electrode terminal portion 710, a second upper relay portion 720, a second upper connection terminal portion 730, a second lower relay portion 740, and a second lower connection terminal portion 750. The second bus bar 700 is formed, for example, by appropriately cutting out and bending a single copper plate, and the second electrode terminal portion 710, the second upper relay portion 720, the three second upper connection terminal portions 730, the second lower relay portion 740, and the second lower connection terminal portion 750 are integrated together.

[0030] The second electrode terminal portion 710 has a substantially rectangular plate shape and covers the second electrodes 520 of the capacitor elements 500. The second electrode terminal portion 710 has a substantially U-shaped notch 711 at its left end, and two substantially rectangular openings 712, 713 at its center and right end. A pair of electrode pins 714 are formed at the upper edges of the notch 711 and the two openings 712, 713. Each pair of electrode pins 714 is joined to the second electrodes 520 of the corresponding capacitor elements 500 by a joining method such as soldering. This electrically connects the second bus bar 700 to the capacitor elements 500.

[0031] A plurality of second protrusions 715 (four in this embodiment) are formed on the upper part of the second electrode terminal 710 so as to be aligned in the left-right direction and protrude rearward. As shown in Fig. 4(b), each of the second protrusions 715 has a substantially flat truncated cone shape, with a tip 715a formed as a circular flat surface and a peripheral surface 715b having a taper. In addition, two circular holes 716 are formed on each of the upper and lower parts of the second electrode terminal 710.

[0032] The second upper relay portion 720 relays between the second electrode terminal portion 710 and the three second upper connection terminal portions 730. The second upper relay portion 720 extends forward from the upper edge of the second electrode terminal portion 710 and then extends slightly upward. Two oval holes 721 and four circular holes 722 are formed in the second upper relay portion 720 so as to be aligned in the left-right direction. In addition, three oval holes 723 are formed in the second upper relay portion 720 in front of these six holes 721, 722 so as to be aligned in the left-right direction.

[0033] The three second upper connection terminal portions 730 are formed at a predetermined interval on the upper edge of the second upper relay portion 720. Each second upper connection terminal portion 730 extends upward from the upper edge of the second upper relay portion 720, with a wide base end and both corners of the tip end having a large R. Each second upper connection terminal portion 730 has a circular mounting hole 731 formed therein.

[0034] The second lower relay portion 740 relays between the second electrode terminal portion 710 and the second lower connection terminal portion 750. The second lower relay portion 740 extends forward from the lower edge of the second electrode terminal portion 710. The second lower relay portion 740 includes a connection portion 741 that extends rearward at its right end portion with the same width as the second lower connection terminal portion 750 and is connected to the second lower connection terminal portion 750.

[0035] The second lower connection terminal portion 750 has a substantially rectangular plate shape and extends downward from the tip of the connection portion 741 of the second lower relay portion 740. The second lower connection terminal portion 750 has a circular mounting hole 751 formed therein.

[0036] Insulating plate 800 is formed from a resin material such as polyphenylene sulfide (PPS), and is interposed between portions that overlap in the front-rear direction of first upper relay portion 620 and three first upper connecting terminal portions 630 of first bus bar 600 and second upper relay portion 720 and three second upper connecting terminal portions 730 of second bus bar 700. Insulating plate 800 ensures insulation between first bus bar 600 and second bus bar 700.

[0037] In capacitor element unit 100, first bottom connection terminal portion 650 of first bus bar 600 and second bottom connection terminal portion 750 of second bus bar 700 are located at the lower right end.

[0038] Fig. 5(a) is a perspective view of the case 200 as viewed from above the front, and Fig. 5(b) is a perspective view of the case 200 as viewed from above the rear. Fig. 6(a) is a perspective view of the right side of the case 200 as viewed from below the front, and Fig. 6(b) is a partial front cross-sectional view of the case 200 showing the periphery of the first through-hole 240 and the second through-hole 250.

[0039] 5(a) to 6(b), the case 200 is made of resin, for example, polyphenylene sulfide (PPS), has a substantially rectangular box shape that is long in the left-right direction, and has an open top. The case 200 is composed of a bottom surface portion 201 that faces an opening 200a on the top surface, and a front side surface portion 202, a rear side surface portion 203, a left side surface portion 204, and a right side surface portion 205 that rise from the bottom surface portion 201 and surround the front, rear, left, and right sides of the bottom surface portion 201, respectively. The front side surface portion 202 and the rear side surface portion 203 are a pair of side surfaces that run along the longitudinal direction of the case 200 and have a relatively large width (dimension in the left-right direction), while the left side surface portion 204 and the right side surface portion 205 are a pair of side surfaces that run along the lateral direction of the case 200 and have a relatively small width (dimension in the front-rear direction).

[0040] Mounting tabs 210 are provided on the outer wall surfaces of the left side surface portion 204 and the right side surface portion 205. Each mounting tab 210 has insertion holes 211 formed on the upper and lower sides. Metal collars 212 are fitted into the insertion holes 211 to increase the strength of the holes. When the film capacitor 1 is installed in an installation portion of an external device, these mounting tabs 210 are fixed to the installation portion with screws or the like.

[0041] A plurality of first ribs 220 and second ribs 230 (six in this embodiment) are formed in the left-right direction on the front side surface portion 202 and the rear side surface portion 203, protruding from the inner wall surface toward the inside of the case 200. That is, the plurality of first ribs 220 and second ribs 230 are disposed so as to be distributed at predetermined intervals over the entire front side surface portion 202 and the rear side surface portion 203 so as to reinforce these side surfaces.

[0042] Each of the first ribs 220 and each of the second ribs 230 extends from the vicinity of the bottom surface portion 201 to the vicinity of the opening 200a. Each of the first ribs 220 and each of the second ribs 230 has a generally rectangular parallelepiped shape that is elongated in the vertical direction and flattened in the front-rear direction. As a result, the tips 221, 231 of each of the first ribs 220 and each of the second ribs 230 form elongated rectangular flat surfaces. The upper ends 222, 232 (ends on the opening 200a side) of each of the first ribs 220 and each of the second ribs 230 are inclined so as to move away from the opening 200a as they approach the inside of the case 200.

[0043] Of the six first ribs 220, the positions of the four first ribs 220 in the center correspond to the positions of the four first protrusions 615 of the first bus bar 600. The left-right dimension of these four first ribs 220 is slightly smaller than the diameter (left-right dimension) of the tip 615a of the first protrusion 615, and the up-down dimension is significantly larger than the diameter (up-down dimension) of the tip 615a of the first protrusion 615.

[0044] Similarly, the positions of the four second ribs 230 in the center of the six second ribs 230 correspond to the positions of the four second protrusions 715 of the second bus bar 700. The left-right dimension of these four second ribs 230 is slightly smaller than the diameter of the tip 715a of the second protrusion 715, and the up-down dimension is significantly larger than the diameter (up-down dimension) of the tip 715a of the second protrusion 715.

[0045] The bottom surface portion 201 has a shape in which the portion 201a near the right end is slightly deeper than the other portions. A substantially rectangular protruding portion 206 that protrudes downward is formed in the portion 201a near the right end, and the thickness of the bottom surface portion 201 at the protruding portion 206 is greater than the thickness of the other portions.

[0046] In the protruding portion 206, a first through hole 240 and a second through hole 250 are formed so as to be aligned in the left-right direction. The first through hole 240 and the second through hole 250 include first holes 241, 251 and second holes 242, 252 continuing to the first holes 241, 251. The second holes 242, 252 are larger and longer (deeper) than the first holes 241, 251. The first holes 241, 251 are located inside the case 200, and the second holes 242, 252 are located outside the case 200.

[0047] First holes 241, 251 have a shape corresponding to the horizontal cross-sectional shape of first lower connection terminal portion 650 and second lower connection terminal portion 750, respectively, i.e., an elongated rectangular shape. The inner wall surfaces of first holes 241, 251 are provided with inclinations 241a, 251a so that the holes widen toward the inside of case 200. The diameters (front-to-back dimensions, left-to-right dimensions) of the smallest openings at the bottom ends of first holes 241, 251 are slightly larger than the diameters (thickness dimensions, width dimensions) of first lower connection terminal portion 650 and second lower connection terminal portion 750, respectively.

[0048] The second holes 242, 252 have a shape corresponding to the planar shape of the sealing member 400, that is, an elliptical shape. The inner wall surfaces of the second holes 242, 252 are formed with a slight draft angle of the mold used when molding the case 200.

[0049] 7(a) and (b) are a perspective view and a plan view, respectively, of the sealing member 400, and FIG. 7(c) is a cross-sectional view taken along line AA' of FIG. 7(b).

[0050] The two sealing members 400 are formed from an elastic material, for example, a rubber material such as silicone rubber, and have an oval cylindrical shape.

[0051] Each sealing member 400 has an elastically deformable annular fin portion 410 formed at the tip and middle portions, which goes around the outer circumferential surface of the sealing member 400. As shown in FIG. 7(c), the fin portion 410 has a cross section similar to a right-angled triangle, with a surface 411 facing the tip direction (upward) inclined while gently convexly curved, and a surface 412 facing the base direction (downward) gently concavely curved. In order to match the draft of the second holes 242 and 252 of the case 200, the height of the fin portion 410 at the tip portion is slightly lower than the height of the fin portion 410 at the middle portion. In addition, each sealing member 400 has a flange portion 420 formed at the base end portion. Furthermore, each sealing member 400 has two elastically deformable annular ribs 430 formed around the inner circumferential surface of the sealing member 400. Each rib 430 has a semicircular cross section. In the longitudinal direction (vertical direction) of the sealing member 400, the rib 430 on the tip side is located between the two fin portions 410, and the rib 430 on the base side is located between the fin portion 410 in the middle portion and the flange portion 420. That is, in the longitudinal direction of the sealing member 400, the positions of the two fin portions 410 and the positions of the two ribs 430 are different.

[0052] The outer diameter of the sealing member 400 including the fin portion 410 is larger than the diameters of the first through-hole 240 and the second holes 242, 252 of the second through-hole 250. In addition, the inner diameter of the sealing member 400 including the rib 430 is smaller than the diameters (thickness, width) of the first lower connecting terminal portion 650 and the second lower connecting terminal portion 750.

[0053] Fig. 8(a) is a side cross-sectional view of film capacitor 1 before being filled with filled resin 300, and Fig. 8(b) is a plan view of the center of film capacitor 1 before being filled with filled resin 300. Fig. 9 is a cross-sectional view of a main part of film capacitor 1 before being filled with filled resin 300, showing the periphery of first through hole 240. For convenience, Fig. 9 shows sealing member 400 in a state before fin portion 410 and rib 430 are deformed.

[0054] The capacitor element unit 100 is accommodated in the case 200 through the opening 200a on the upper surface of the case 200. At this time, the first lower connection terminal portion 650 of the first bus bar 600 is led out through the first through hole 240, and the second lower connection terminal portion 750 of the second bus bar 700 is led out through the second through hole 250. At this time, the first holes 241, 251 of the first through hole 240 and the second through hole 250 are expanded toward the inside of the case 200, so that the first lower connection terminal portion 650 and the second lower connection terminal portion 750 can be easily inserted into the first through hole 240 and the second through hole 250 inside the case 200. The positions of the first lower connection terminal portion 650 and the second lower connection terminal portion 750 that are passed through the first through hole 240 and the second through hole 250 are restricted by the first holes 241, 251.

[0055] When the capacitor element unit 100 is inserted into the case 200, the first electrode terminal portion 610 of the first bus bar 600 faces the front side surface portion 202, and the four first protrusion portions 615 of the first electrode terminal portion 610 abut against the four first ribs 220 in the center of the front side surface portion 202 at a position closer to the opening 200a than the upper portion of the case 200, i.e., the bottom surface portion 201. Similarly, the second electrode terminal portion 710 of the second bus bar 700 faces the rear side surface portion 203, and the four second protrusion portions 715 of the second electrode terminal portion 710 abut against the four second ribs 230 in the center of the rear side surface portion 203 at the upper portion of the case 200.

[0056] At this time, the flat surfaces of the tips 221, 615a of the first rib 220 and the first protrusion 615 abut against each other, and the flat surfaces of the tips 231, 715a of the second rib 230 and the second protrusion 715 abut against each other. Therefore, even if the positions of the first rib 220 and the first protrusion 615 or the positions of the second rib 230 and the second protrusion 715 are slightly misaligned in the left-right direction, they can be reliably abutted against each other. Furthermore, the diameter (left-right dimension) of the tips 615a, 715a of the first protrusion 615 and the second protrusion 715 is larger than the width (left-right dimension) of the tips 221, 231 of the first rib 220 and the second rib 230, so that the first rib 220 and the first protrusion 615, and the second rib 230 and the second protrusion 715 can be more reliably abutted against each other while suppressing an increase in the amount of resin in the case 200 due to the wider width of the first rib 220 and the second rib 230.

[0057] In addition, upper ends 222, 232 of first rib 220 and second rib 230 and lower sides of peripheral surfaces 615b, 715b of first protrusion 615 and second protrusion 715, i.e., the bottom surface 201 side, are inclined so as to move away from opening 200a toward the inside of case 200. This makes it difficult for first protrusion 615 and second protrusion 715 to get caught on upper ends 222, 232 of first rib 220 and second rib 230 when capacitor element unit 100 is inserted into case 200 from above. Therefore, capacitor element unit 100 can be smoothly accommodated in case 200.

[0058] After the capacitor element unit 100 is accommodated in the case 200, the sealing member 400 is inserted from the outside of the case 200 into the first lower connection terminal portion 650 and the second lower connection terminal portion 750, and into the second holes 242, 252 of the first through hole 240 and the second through hole 250. When the sealing member 400 is pushed into the second holes 242, 252 until the flange portion 420 abuts against the wall surface surrounding the second holes 242, 252 in the overhanging portion 206 of the case 200, the attachment of the sealing member 400 is completed. By confirming that the flange portion 420 abuts against the wall surface of the overhanging portion 206, it can be confirmed that the sealing member 400 is completely attached.

[0059] 9, the sealing member 400 is interposed between the outer surface of the first lower connection terminal portion 650 and the inner wall surface of the second hole 242 of the first through hole 240, thereby sealing the gap between the first lower connection terminal portion 650 and the first through hole 240. The two fin portions 410 on the outer peripheral surface of the sealing member 400 are tilted downward, i.e., in the direction opposite to the insertion direction of the sealing member 400 into the first through hole 240, and are deformed so as to shrink inward, so that they come into contact with the inner wall surface of the second hole 242 around the entire circumference. Each fin portion 410 is pressed against the inner wall surface of the second hole 242.

[0060] Furthermore, the two ribs 430 on the inner peripheral surface of the sealing member 400 deform so as to shrink inward and come into contact with the outer surface of the first lower connecting terminal portion 650 over the entire circumference. Each rib 430 is pressed against the outer surface of the first lower connecting terminal portion 650. The parts of the inner peripheral surface of the sealing member 400 other than the ribs 430 do not come into contact with the outer surface of the first lower connecting terminal portion 650. This makes it easier to insert the sealing member 400 into the first lower connecting terminal portion 650.

[0061] The length from the tip of the sealing member 400 to just before the flange portion 420 is shorter than the length of the second hole 242. As a result, a small gap is formed between the wall surface between the first hole 241 and the second hole 242 of the first through-hole 240 and the tip surface of the sealing member 400.

[0062] Similarly, sealing member 400 is interposed between the outer surface of second lower connecting terminal portion 750 and the inner wall surface of second hole 252 of second through hole 250, sealing the gap between second lower connecting terminal portion 750 and second through hole 250. The two fin portions 410 deform to abut against the inner wall surface of second hole 252 over the entire periphery, and the two ribs 430 deform to abut against the outer surface of second lower connecting terminal portion 750 over the entire periphery. A small gap is formed between the wall surface between first hole 251 and second hole 252 of second through hole 250 and the tip surface of sealing member 400.

[0063] In addition, the fin portion 410 of the sealing member 400 has a surface 411 that faces the tip direction, i.e., the insertion direction, inclined. This reduces the resistance that occurs when inserting the sealing member 400 into the second holes 242, 252, making it easier to insert the sealing member 400 into the second holes 242, 252.

[0064] Filling resin 300 in a liquid state is injected through opening 200a into case 200 housing capacitor element unit 100, and is stored. At this time, the gap between first lower connection terminal portion 650 and first through hole 240 is sealed with sealing member 400, and the gap between second lower connection terminal portion 750 and second through hole 250 is sealed with sealing member 400. This prevents filling resin 300 in a liquid state from leaking out of case 200 from first through hole 240 and second through hole 250.

[0065] In particular, the fin portion 410 of the sealing member 400 adheres strongly to the inner wall surfaces of the second holes 242, 252 of the first through hole 240 and the second through hole 250 due to a pressing force (stress) generated by the deformation of the fin portion 410, so that the gap between the sealing member 400 and the inner wall surfaces of the second holes 242, 252 is tightly blocked. This effectively prevents leakage of the filling resin 300 from between the sealing member 400 and the second holes 242, 252.

[0066] Furthermore, since ribs 430 of sealing member 400 are tightly adhered to the outer surfaces of first lower connecting terminal portion 650 and second lower connecting terminal portion 750 by the pressing force (stress) generated by the deformation of ribs 430, the gap between sealing member 400 and the outer surfaces of first lower connecting terminal portion 650 and second lower connecting terminal portion 750 is tightly blocked. This effectively prevents leakage of filling resin 300 from between sealing member 400 and the outer surfaces of first lower connecting terminal portion 650 and second lower connecting terminal portion 750.

[0067] Furthermore, since the second holes 242, 252 are blocked from the outside of the case 200 by the flange portion 420 of the sealing member 400, the filling resin 300 is further prevented from leaking from the first through hole 240 and the second through hole 250 to the outside of the case 200.

[0068] A portion of the filling resin 300 injected into the case 200 flows between the front side surface portion 202 and the first electrode terminal portion 610 and between the rear side surface portion 203 and the second electrode terminal portion 710 .

[0069] The vertical dimension of the first protrusion 615 (the direction in which the opening 200a and the bottom surface portion 201 are aligned) is smaller than the vertical dimension of the first rib 220, and at the position of the four first ribs 220 in the center, a gap is generated between the first electrode terminal portion 610 and the first rib 220 in the vertical direction except for the portion where the first rib 220 and the first protrusion 615 contact each other. Similarly, the vertical dimension of the second protrusion 715 is smaller than the vertical dimension of the second rib 230, and at the position of the four second ribs 230 in the center, a gap is generated between the second electrode terminal portion 710 and the second rib 230 in the vertical direction except for the portion where the second rib 230 and the second protrusion 715 contact each other. As a result, the filling resin 300 can move smoothly in the left-right direction at the positions of the first rib 220 and the second rib 230, and spreads well between the front side portion 202 and the first electrode terminal portion 610 and between the rear side portion 203 and the second electrode terminal portion 710.

[0070] Furthermore, the filling resin 300 that flows into the case 200 flows through each of the holes 616, 621 provided in the first bus bar 600 and each of the holes 716, 721, 722, 723 provided in the second bus bar 700, and thereby spreads well to the inside of the capacitor element unit 100, i.e., between the first bus bar 600 and the second bus bar 700 and the three capacitor elements 500.

[0071] When the injection of the filled resin 300 into the case 200 is completed, the case 200 is heated, whereby the filled resin 300 in the case 200 hardens. The hardened filled resin 300 is then cooled, during which the filled resin 300 may shrink. At this time, a stress is generated in the front side surface portion 202, the rear side surface portion 203, the left side surface portion 204, and the right side surface portion 205 of the case 200, which is pulled toward the inside of the case 200 by the filling resin 300 which tends to shrink.

[0072] The front side portion 202 and the rear side portion 203 are reinforced by six first ribs 220 and six second ribs 230. Furthermore, the four first ribs 220 and four second ribs 230 in the center abut against the first protrusion 615 and the second protrusion 715, so that the front side portion 202 and the rear side portion 203 are supported by the first protrusion 615 and the second protrusion 715 from the inside of the case 200. This strongly suppresses the warping of the front side portion 202 and the rear side portion 203 toward the inside of the case 200. In particular, the front side portion 202 and the rear side portion 203 are prone to warping at the upper side near the opening 200a, but since the first protrusion 615 and the second protrusion 715 are located at the upper portion, the warping of the front side portion 202 and the rear side portion 203 can be effectively suppressed.

[0073] On the other hand, left side surface portion 204 and right side surface portion 205 have small dimensions in the front-to-rear direction, and are reinforced by mounting tabs 210 formed on the outer wall surfaces. This prevents left side surface portion 204 and right side surface portion 205 from warping toward the inside of case 200, even without the configuration of first rib 220, second rib 230, and first protrusion portion 615 and second protrusion portion 715.

[0074] In this manner, the film capacitor 1 is completed as shown in FIGS. 1(a) and (b).

[0075] The film capacitor 1 is mounted on various external devices such as an inverter device provided in an electric vehicle. A pair of external terminals (not shown) provided on the external device or the like and corresponding to the connection terminals 630, 730 are connected to the first upper connection terminal portion 630 and the second upper connection terminal portion 730. In addition, a pair of external terminals (not shown) provided on the external device and corresponding to the connection terminals 650, 750 are connected to the first lower connection terminal portion 650 and the second lower connection terminal portion 750.

[0076] Note that the front-rear and left-right directions of the film capacitor 1 when mounted on an external device are not necessarily the same as those shown in this embodiment, i.e., the opening 200a of the case 200 faces upward and the bottom surface 201 faces downward. For example, the film capacitor 1 may be installed on an external device so that the rear side surface 203 faces downward. If strong cooling of the film capacitor 1 is required, a cooler (not shown) is attached to the outer surface of the rear side surface 203. In this case, the flatness of the rear side surface 203 of the film capacitor 1 is high, improving the adhesion of the cooler and achieving good cooling performance.

[0077] <Effects of the embodiment> As described above, according to the present embodiment, the following effects are achieved.

[0078] The film capacitor 1 includes an annular sealing member 400 interposed between the outer surface of the first lower connection terminal portion 650 (second lower connection terminal portion 750) and the inner wall surface of the first through hole 240 (second through hole 250). The sealing member 400 has a deformable annular fin portion 410 on its outer surface. The outer diameter of the sealing member 400 including the fin portion 410 is larger than the diameter of the first through hole 240 (second through hole 250), and the fin portion 410 deforms to come into contact with the inner wall surface of the first through hole 240 (second through hole 250).

[0079] According to this configuration, the gap between the first lower connection terminal portion 650 (the second lower connection terminal portion 750) and the first through hole 240 (the second through hole 250) is sealed by the sealing member 400, so that the filling resin 300 in a liquid phase is prevented from leaking from the first through hole 240 (the second through hole 250) to the outside of the case 200. In particular, the gap between the sealing member 400 and the inner wall surface of the first through hole 240 (the second through hole 250) is strongly blocked by the fin portion 410, so that the filling resin 300 can be effectively prevented from leaking from between the sealing member 400 and the first through hole 240 (the second through hole 250). Moreover, it is only necessary to attach the sealing member 400 to the first through hole 240 (the second through hole 250), and the filling resin 300 can be easily prevented from leaking from the first through hole 240 (the second through hole 250).

[0080] In addition, the film capacitor 1 is configured such that the sealing member 400 includes a flange portion 420 that abuts against the wall surface surrounding the first through hole 240 (second through hole 250) on the outside of the case 200 to block the first through hole 240 (second through hole 250) from the outside of the case 200.

[0081] According to this configuration, the filling resin 300 is further prevented from leaking out of the case 200 through the first through hole 240 (the second through hole 250).

[0082] Furthermore, the film capacitor 1 is configured such that the first through hole 240 (second through hole 250) includes a first hole 241 (251) and a second hole 242 (252) continuous with the first hole 241 (251), the second hole 242 (252) is larger than the first hole 241 (251), and the sealing member 400 is disposed in the second hole 242 (252).

[0083] According to this configuration, the first hole 241 (251) regulates the position of the first lower connection terminal portion 650 (second lower connection terminal portion 750), while the sealing member 400 seals the space between the first lower connection terminal portion 650 (second lower connection terminal portion 750) and the second hole 242 (252).

[0084] Furthermore, the film capacitor 1 is configured so that the first hole 241 (251) is located inside the case 200, and the second hole 242 (252) is located outside the case 200.

[0085] According to this configuration, since the sealing member 400 can be inserted into the second hole 242 (252) from the outside of the case 200, the sealing member 400 can be easily attached to the case 200.

[0086] Furthermore, in the film capacitor 1, the sealing member 400 has a deformable annular rib 430 on its inner surface. The inner diameter of the sealing member 400 including the rib 430 is smaller than the diameter of the first lower connection terminal portion 650 (second lower connection terminal portion 750), and the rib 430 deforms to come into contact with the outer surface of the first lower connection terminal portion 650 (second lower connection terminal portion 750).

[0087] According to this configuration, the rib 430 tightly seals the gap between the sealing member 400 and the outer surface of the first lower connecting terminal portion 650 (second lower connecting terminal portion 750), thereby effectively preventing leakage of the filling resin 300 from between the sealing member 400 and the first lower connecting terminal portion 650 (second lower connecting terminal portion 750).

[0088] Furthermore, film capacitor 1 is configured such that, in the longitudinal direction of sealing member 400, fin portions 410 and ribs 430 are positioned at different positions.

[0089] With this configuration, the positions of the stress applied to the inner wall surface of the first through hole 240 (second through hole 250) by the fin portion 410 and the stress applied to the outer surface of the first lower connection terminal portion 650 (second lower connection terminal portion 750) by the rib 430 can be dispersed in the longitudinal direction of the sealing member 400, making it easier to insert the sealing member 400 into the first through hole 240 (second through hole 250).

[0090] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and application examples of the present invention can be modified in various ways in addition to the above embodiment.

[0091] For example, in the above embodiment, two fin portions 410 having a cross section resembling a right-angled triangle are formed on the outer peripheral surface of sealing member 400. However, the shape of fin portions 410 is not limited to the above shape and can be changed as appropriate, and the number of fin portions 410 can also be changed as appropriate depending on the length of sealing member 400, etc.

[0092] In the above embodiment, two ribs 430 having a semicircular cross section are formed on the inner circumferential surface of the sealing member 400. However, the shape of the ribs 430 is not limited to the above shape and can be changed as appropriate, and the number of ribs 430 can also be changed as appropriate depending on the length of the sealing member 400, etc. Furthermore, the sealing member 400 may be configured such that the ribs 430 are not provided on the inner circumferential surface, and the entire inner circumferential surface is in close contact with the outer surface of the first lower connecting terminal portion 650 (second lower connecting terminal portion 750).

[0093] Furthermore, in the above embodiment, the flange portion 420 is provided on the sealing member 400. However, the sealing member 400 may be configured not to be provided with the flange portion 420.

[0094] Furthermore, in the above embodiment, the first through hole 240 and the second through hole 250 are configured by the first holes 241, 251 and the second holes 242, 252. However, the first through hole 240 and the second through hole 250 may be configured so that the first holes 241, 251 are not included and the second holes 242, 252 are connected to the inside of the case 200. In this case, the length of the sealing member 400 may be changed in response to the change in the length of the second holes 242, 252.

[0095] In the above embodiment, first through hole 240 and second through hole 250 are provided in bottom surface portion 201 of case 200. However, first through hole 240 and second through hole 250 may be provided in any of front side surface portion 202, rear side surface portion 203, left side surface portion 204, and right side surface portion 205 of case 200. Also, first through hole and second through hole may be provided in a plurality of side surface portions of case 200, and first bus bar 600 and second bus bar 700 may be provided with connection terminal portions corresponding to those through holes.

[0096] Furthermore, in the above embodiment, the capacitor element unit 100 includes three capacitor elements 500. However, the number of capacitor elements 500 can be changed as appropriate, including the case where the number is one.

[0097] Furthermore, in the above embodiment, capacitor element 500 is formed by stacking two metallized films having aluminum vapor-deposited on a dielectric film and rolling or laminating the stacked metallized films, but capacitor elements 500 may also be formed by stacking a metallized film having aluminum vapor-deposited on both sides of a dielectric film and an insulating film, and rolling or laminating the resulting film.

[0098] Furthermore, in the above embodiment, the film capacitor 1 is given as an example of the capacitor of the present invention. However, the present invention can be applied to capacitors other than the film capacitor 1.

[0099] 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.

[0100] In addition, in the description of the above embodiment, terms indicating directions such as "upper" and "lower" indicate relative directions that depend only on the relative positional relationship of the components, and do not indicate absolute directions such as the vertical direction or the horizontal direction. [Industrial Applicability]

[0101] The present invention is useful for capacitors used in various electronic devices, electric devices, industrial devices, vehicle electrical equipment, and the like. [Explanation of symbols]

[0102] 1. Film capacitor (capacitor) 200 cases 240 First through hole (through hole) 241 Hole 1 242 Hole 2 250 Second through hole (through hole) 251 Hole 1 252 Hole 2 300 Filled Resin 400 Sealing material 410 Fin part (first protrusion part) 420 Flange section (blocking section) 430 Rib (second protrusion) 500 Capacitor element 510 1st electrode (electrode) 520 2nd electrode (electrode) 600 1st bus bar (bus bar) 650 First lower connection terminal part (connection terminal part) 700 2nd bus bar (bus bar) 750 Second lower connection terminal part (connection terminal part)

Claims

1. A capacitor element; a bus bar connected to an electrode of the capacitor element and including a connection terminal portion connectable to an external terminal; a case in which the capacitor element is housed and which has a through hole through which the connection terminal portion is led out to the outside; A filling resin filled in the case; a ring-shaped sealing member that is inserted into the through hole and is interposed between an outer surface of the connection terminal portion and an inner wall surface of the through hole, the sealing member has a deformable annular first protrusion on its outer surface; an outer diameter of the sealing member including the first protrusion portion is larger than a diameter of the through hole, the first protrusion is deformed so as to fall in a direction opposite to an insertion direction when the sealing member is inserted into the through hole, thereby contacting an inner wall surface of the through hole, and a surface facing the insertion direction is inclined. A capacitor characterized by:

2. The capacitor according to claim 1, the through hole has a gradient such that the diameter of the through hole increases toward an outer side of the case, the sealing member has two first protrusions, a height of the first protrusion located closer to the inside of the case in the through hole is lower than a height of the first protrusion located closer to the outside of the case in the through hole; A capacitor characterized by:

3. The capacitor according to claim 1 or 2, the sealing member includes a closing portion that comes into contact with a wall surface surrounding the through hole on the outside of the case to close the through hole from the outside of the case. A capacitor characterized by:

4. The capacitor according to any one of claims 1 to 3, The through hole includes a first hole and a second hole communicating with the first hole, The second hole is larger than the first hole, The sealing member is disposed in the second hole. A capacitor characterized by:

5. 5. The capacitor according to claim 4, The first hole is located inside the case, and the second hole is located outside the case. A capacitor characterized by:

6. The capacitor according to any one of claims 1 to 5, the sealing member has a deformable annular second protrusion on an inner surface thereof; an inner diameter of the sealing member including the second protrusion portion is smaller than a diameter of the connection terminal portion; the second protrusion is deformed to come into contact with an outer surface of the connection terminal; A capacitor characterized by:

7. 7. The capacitor according to claim 6, The position of the first protrusion and the position of the second protrusion are different in the longitudinal direction of the sealing member. A capacitor characterized by:

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