WO2019181109A1

WO2019181109A1 - Capacitor

Info

Publication number: WO2019181109A1
Application number: PCT/JP2018/046004
Authority: WO
Inventors: 史和前野; 三浦　寿久; 英里子金谷
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2018-03-20
Filing date: 2018-12-14
Publication date: 2019-09-26
Also published as: JPWO2019181109A1

Abstract

This film capacitor is provided with: a capacitor element; a case 200 in which the capacitor element is accommodated; protrusions 260 disposed on each of the left surface 204 and the right surface 205 inside the case 200 and extending from the bottom surface 201 of the case 200 toward an opening 200a; and a filling resin filling the inside of the case 200, and which has a coefficient of linear expansion different from that of the case 200. Here, the filling resin fills the inside of the case 200 up to a level higher than an upper end surface 261 of the protrusion 260. Support columns 250 supporting a capacitor element unit including the capacitor element from the bottom surface 201 are provided on each of the left surface 204 and the right surface 205. A plurality of protrusions 260 are provided in regions of the left surface 204 and the right surface 205 in which the support columns are not provided, and protrude a shorter distance from the left surface 204 and the right surface 205 than the support columns 250.

Description

Capacitor

The present invention relates to a capacitor.

In a metallized film capacitor in which the capacitor element is housed in a resin case and filled with epoxy resin, a clog-like protrusion is formed on the inside of the side surface of the resin case, and between the side surface and the capacitor element. Patent Document 1 discloses that the thickness of the epoxy resin corresponding to the height of the protrusion is secured. The clogged tooth-like protrusion extends from the bottom surface of the resin case to the open end (upper end), and the upper end surface of the protrusion is exposed from the epoxy resin. The resin case is made of a material different from the epoxy resin, for example, polybutylene terephthalate.

JP 2007-227696 A

Metallized film capacitors can be used in various environments depending on their applications. For example, when a metallized film capacitor is used in an environment with a large temperature change, due to the difference in coefficient of linear expansion (thermal expansion coefficient) between the resin case and the epoxy resin, the side surface of the resin case and the epoxy resin Cracks and delamination are likely to occur between them.

In particular, if a crack or peeling occurs on the casting surface (exposed surface) of the epoxy resin between the side surface of the resin case, it will start from the crack and peel to the bottom side of the resin case. Is easy to progress. Therefore, in order to sufficiently suppress cracking and peeling, it is important to strengthen the adhesion between the side surface of the resin case and the epoxy resin at the cast resin surface of the epoxy resin.

In the configuration of Patent Document 1, since the upper end surface of the tooth-like protrusion of the clogs is exposed from the epoxy resin, the adhesion between the side surface of the resin case and the epoxy resin cannot be enhanced at the portion of the casting surface of the epoxy resin. It is difficult to sufficiently prevent cracks and peeling between the side surface of the case and the epoxy resin.

In view of such a problem, an object of the present invention is to provide a capacitor in which cracks and peeling are unlikely to occur between a side surface of a case and a filling resin.

The capacitor according to the first aspect of the present invention includes a capacitor element, a case in which the capacitor element is accommodated, a protrusion provided on a side surface in the case and extending from the bottom surface side of the case to the opening side, Filling resin filled in the case. Here, the case is filled with the filling resin up to a position higher than the end face of the protrusion on the opening side of the case.

According to the present invention, it is possible to provide a capacitor that is unlikely to crack or peel between the side surface of the case and the filling resin.

The effect or significance of the present invention will become more apparent from the following description of embodiments. However, the embodiment described below is merely an example when the present invention is implemented, and the present invention is not limited to what is described in the following embodiment.

FIG. 1A is a perspective view of a film capacitor as viewed from the front according to the embodiment, and FIG. 1B is a perspective view of the film capacitor as viewed from the rear according to the embodiment. 2A is a perspective view of the capacitor element unit viewed from the front according to the embodiment, and FIG. 2B is a perspective view of the capacitor element unit viewed from the rear according to the embodiment. is there. FIG. 3 is a perspective view showing the first bus bar, the second bus bar, and the insulating plate in an exploded state according to the embodiment. FIG. 4A is a perspective view of the case according to the embodiment as viewed from the front, and FIG. 4B is a perspective view of the case as viewed from the rear according to the embodiment. FIG. 5 is a cross-sectional perspective view of the left end portion of the case according to the embodiment. FIG. 6 is a cross-sectional perspective view of the right end portion of the case according to the embodiment. FIG. 7 is a partially enlarged plan view in which the central portion of the left side surface of the case filled with the filling resin according to the embodiment is enlarged. FIG. 8 is a cross-sectional perspective view of the left end portion of the case according to the first modification.

Hereinafter, a film capacitor 1 which is an embodiment of the capacitor of the present invention will be described with reference to the drawings. For convenience, front and rear, left and right, and up and down directions are appropriately appended to each drawing. In addition, the direction of illustration shows the relative direction of the film capacitor 1 to the last, and does not show an absolute direction.

In the present embodiment, the film capacitor 1 corresponds to a “capacitor” described in the claims. Further, the left side surface 204 and the right side surface 205 correspond to “side surfaces” recited in the claims. Furthermore, the upper end surface 261 corresponds to an “end surface on the opening side” recited in the claims. Furthermore, the first bus bar 500 and the second bus bar 600 correspond to the “bus bar” described in the claims. Furthermore, the protrusion 713 and the recess 251 constitute a “positioning portion” described in the claims.

However, the above description is only for the purpose of associating the configuration of the claims with the configuration of the embodiment, and the invention described in the claims is incorporated into the configuration of the embodiment by the above association. It is not limited at all.

FIG. 1A is a perspective view of the film capacitor 1 as viewed from the front according to the present embodiment, and FIG. 1B is a perspective view of the film capacitor 1 as viewed from the rear according to the present embodiment. FIG. In addition, illustration of the filling resin 300 is abbreviate | omitted in FIG.1 (b).

1 (a) and 1 (b), the film capacitor 1 includes a capacitor element unit 100, a case 200, and a filling resin 300. Capacitor element unit 100 is housed in case 200, and filling resin 300 is filled in case 200. The filling resin 300 is a thermosetting resin, for example, an epoxy resin. Most of the capacitor element unit 100 embedded in the filling resin 300 is protected from moisture and impact by the case 200 and the filling resin 300.

2A is a perspective view of the capacitor element unit 100 viewed from the front according to the present embodiment, and FIG. 2B is a capacitor element unit 100 viewed from the rear according to the present embodiment. FIG. FIG. 3 is a perspective view showing first bus bar 500, second bus bar 600, and insulating plate 700 in an exploded state according to the present embodiment.

2A to 3, the capacitor element unit 100 includes two capacitor elements 400, a first bus bar 500, a second bus bar 600, and an insulating plate 700.

The capacitor element 400 is formed by stacking two metallized films on which aluminum is vapor-deposited on a dielectric film, winding or stacking the stacked metallized films, and pressing them flatly. In the capacitor element 400, a first end face electrode 410 is formed on one end face by spraying a metal such as zinc, and a second end face electrode 420 is also formed on the other end face by spraying a metal such as zinc. The The two capacitor elements 400 are arranged in the left-right direction so that their circumferential surfaces face each other, and in this state, the first bus bar 500 and the second bus bar 600 are connected to the capacitor elements 400.

The capacitor element 400 of the present embodiment is formed of a metallized film in which aluminum is vapor-deposited on a dielectric film, but in addition to this, metallization in which other metals such as zinc and magnesium are vapor-deposited. It may be formed by a film. Alternatively, the capacitor element 400 may be formed of a metallized film in which a plurality of metals are vapor-deposited among these metals, or may be formed of a metallized film in which an alloy of these metals is vapor-deposited. .

The first bus bar 500 is formed of a conductive material, for example, a copper plate, and includes a first main body 510, a first electrode terminal 520, a first front connection terminal 530, and a first rear connection terminal 540. Including. The first bus bar 500 is formed by, for example, appropriately cutting and bending a single copper plate, and the first main body 510, the first electrode terminal 520, the first front connection terminal 530, and the first rear. The connection terminal portion 540 is integrated.

The first main body 510 has a substantially rectangular plate shape that is long in the left-right direction. In the first main body 510, three oval openings 511 are formed. The first electrode terminal portion 520 has a substantially rectangular plate shape, and extends downward from the front end edge of the first main body portion 510. Two electrode pins 521 are formed at a position corresponding to each capacitor element 400 at the lower end edge of the first electrode terminal portion 520.

The first front connection terminal portion 530 is provided at the front end edge of the left end of the first main body portion 510, extends upward from the front end edge, then bends forward, extends forward, and further narrowed downward. After being bent and extending greatly downward, it is bent to the left, slightly bent forward, then bent to the left and extended to the left. A circular attachment hole 532 is formed in the connection portion 531 at the tip of the first front connection terminal portion 530. Further, two positioning holes 533 are formed in the first front connection terminal portion 530 at a portion overlapping the insulating plate 700 in the vertical direction.

The first rear connection terminal portion 540 is provided at the rear end edge of the right end of the first main body 510, extends upward from the rear end edge, then bends rearward, extends rearward, and is further reduced in width. It is bent downward and extends downward, and then bent rearward and greatly extended backward, and then bent downward and extended downward. A circular attachment hole 542 is formed in the connection portion 541 at the tip of the first rear connection terminal portion 540. Further, two positioning holes 543 are formed in the first rear connection terminal portion 540 at a portion overlapping the insulating plate 700 in the vertical direction.

The second bus bar 600 is formed of a conductive material, for example, a copper plate, and includes a second main body portion 610, a second electrode terminal portion 620, a second front connection terminal portion 630, and a second rear connection terminal portion 640. Including. The second bus bar 600 is formed by, for example, appropriately cutting and bending a single copper plate, and the second main body 610, the second electrode terminal 620, the second front connection terminal 630, and the second rear. The connection terminal portion 640 is integrated.

The second main body 610 has a substantially rectangular plate shape that is long in the left-right direction. Three oval openings 611 are formed in the second main body 610. The second electrode terminal portion 620 has a substantially elongated rectangular plate shape and extends downward from the rear end edge of the second main body portion 610. Two electrode pins 621 are formed at a position corresponding to each capacitor element 400 at the lower end edge of the second electrode terminal portion 620.

The second front connection terminal portion 630 is provided on the left side of the front end edge of the second main body portion 610, extends upward from the front end edge, and then bends forward and extends forward, and further bent downward and greatly downward. Extend. The second front connection terminal portion 630 has a significantly wider left and right width than the first front connection terminal portion 530, and the connection portions 631 are provided on the left and right sides of the tip portion. A circular attachment hole 632 is formed in each connection portion 631. Further, two positioning holes 633 are formed in the second front connection terminal portion 630 at a portion overlapping the insulating plate 700 in the vertical direction.

The second rear connection terminal portion 640 is provided at the rear end edge of the right end of the second main body portion 610, extends upward from the rear end edge, then bends rearward, extends rearward, and is further reduced in width. It bends downward and extends downward, then bent rightward and then bent backwards, bent slightly downward and greatly extended backward, then bent rightward and extended rightward. A circular attachment hole 642 is formed in the connection portion 641 at the tip of the second rear connection terminal portion 640. Further, two positioning holes 643 are formed in the second rear connection terminal portion 640 at a portion overlapping the insulating plate 700 in the vertical direction. Further, the second rear connection terminal portion 640 is formed with a square hole 644 at a portion that greatly extends rearward.

The insulating plate 700 is formed of a resin such as polyphenylene sulfide (PPS) and has an insulating property. The insulating plate 700 includes a first insulating part 710, a second insulating part 720, and a third insulating part 730.

The first insulating portion 710 has a substantially rectangular plate shape that is long in the left-right direction. Three oval openings 711 are formed in the first insulating portion 710. Further, the first insulating portion 710 is formed with an oval annular rib 712 around the periphery of the two left and right openings 711 among the three openings 711. Further, the first insulating portion 710 has two front and rear protrusions 713 at the left and right ends.

The second insulating part 720 is provided on the left side of the front edge of the first insulating part 710. The second insulating part 720 is formed in a size corresponding to the first front connection terminal part 530 and the second front connection terminal part 630 and has a bowl shape. Two positioning projections 721 are formed in the second insulating portion 720 at positions corresponding to the two positioning holes 633 of the second front connection terminal portion 630 on the front surface side, and 2 of the first front connection terminal portion 530 on the back surface side. Two positioning projections 722 are formed at positions corresponding to the two positioning holes 533.

The third insulating portion 730 is provided at the right end of the rear end edge of the first insulating portion 710. The third insulating portion 730 is formed in a size corresponding to the first rear connection terminal portion 540 and the second rear connection terminal portion 640 and has an inverted L-shaped plate shape. Two positioning projections 731 are formed in the third insulating portion 730 at positions corresponding to the two positioning holes 643 of the second rear connection terminal portion 640 on the front surface side, and 2 of the first rear connection terminal portion 540 on the back surface side. Two positioning projections 732 are formed at positions corresponding to the two positioning holes 543.

When the capacitor element unit 100 is assembled, first, the second bus bar 600 is overlaid on the insulating plate 700 from above, and the first bus bar 500 is overlaid on the insulating plate 700 from below. At this time, the positioning

protrusions

721 and 731 of the insulating plate 700 are fitted into the positioning holes 633 and 643 of the second bus bar 600. Further, the two left and right annular ribs 712 of the insulating plate 700 are fitted into the two left and right openings 611 of the second bus bar 600. Further, the positioning

protrusions

722 and 732 of the insulating plate 700 are fitted into the positioning holes 533 and 543 of the first bus bar 500. As a result, the first bus bar 500 and the second bus bar 600 are positioned and fixed in the front-rear and left-right directions with respect to the insulating plate 700. In addition, the three openings 511 of the first bus bar 500, the three openings 611 of the second bus bar 600, and the three openings 711 of the insulating plate 700 are aligned.

Next, the first bus bar 500 and the second bus bar 600 are connected to the two capacitor elements 400. That is, each electrode pin 521 of the first electrode terminal portion 520 of the first bus bar 500 is joined to the first end face electrode 410 of each capacitor element 400 by a joining method such as soldering. Thereby, the first bus bar 500 is electrically connected to the first end face electrode 410. Similarly, each electrode pin 621 of the second electrode terminal portion 620 of the second bus bar 600 is joined to the second end face electrode 420 of each capacitor element 400 by a joining method such as soldering. As a result, the second bus bar 600 is electrically connected to the second end face electrode 420. Thus, the capacitor element unit 100 is completed.

The first main body portion 510 of the first bus bar 500 and the second main body portion 610 of the second bus bar 600 overlap vertically with the first insulating portion 710 of the insulating plate 700 interposed therebetween. Further, a part of the first front connection terminal part 530 of the first bus bar 500 and a part of the second front connection terminal part 630 of the second bus bar 600 are vertically arranged with the second insulation part 720 of the insulating plate 700 interposed therebetween. overlap. Further, a part of the first rear connection terminal part 540 of the first bus bar 500 and a part of the second rear connection terminal part 640 of the second bus bar 600 are vertically moved with the third insulation part 730 of the insulating plate 700 interposed therebetween. overlap. Thereby, ESL (equivalent series inductance) which the 1st bus bar 500 and the 2nd bus bar 600 have can be reduced effectively.

FIG. 4A is a perspective view of the case 200 viewed from the front according to the present embodiment, and FIG. 4B is a perspective view of the case 200 viewed from the rear according to the present embodiment. is there. FIG. 5 is a cross-sectional perspective view of the left end portion of the case 200 according to the present embodiment. FIG. 6 is a cross-sectional perspective view of the right end portion of case 200 according to the present embodiment.

The case 200 is made of resin, and is formed of, for example, polyphenylene sulfide (PPS) which is a thermoplastic resin. The case 200 is formed in a substantially rectangular parallelepiped box shape, and has a bottom surface 201, a front side surface 202, a rear side surface 203, a left side surface 204, and a right side surface 205 rising from the bottom surface 201, and the top surface is open. In the bottom surface 201, both ends 201a connected to the left side surface 204 and the right side surface 205 have a curved shape. In addition, the bottom surface 201 has a concave central portion 201b, so that the inner wall surface of the central portion 201b is raised. In the case 200, the left-right direction in which the two capacitor elements 400 to be accommodated are aligned is the longitudinal direction, and the front-rear direction in which both end faces of the two capacitor elements 400 are facing is the short direction.

In the case 200, a first front terminal block 210 and a second front terminal block 220 are formed on the left end portion of the outer wall surface of the front side surface 202 and a portion slightly left of the center portion, respectively. The first front terminal block 210 has a substantially rectangular parallelepiped shape that is long in the vertical direction, and two metal nuts 212 are embedded in the installation surface 211 on the front surface so as to be lined up and down. The second front terminal block 220 has a substantially cubic shape, and a metal nut 222 is embedded in the installation surface 221 on the front surface thereof. The vertical position of the nut 222 of the second front terminal block 220 is equal to the vertical position of the nut 212 on the upper side of the first front terminal block 210.

In the case 200, a rear terminal block 230 is formed at the right end of the outer wall surface of the rear side surface 203. The rear terminal block 230 has a substantially rectangular parallelepiped shape that is long in the up and down and front and back directions, and two metal nuts 232 are embedded in the installation surface 231 on the front surface thereof so as to be lined up and down. A claw 233 and a hook 234 are formed on the left side surface of the rear terminal block 230.

Furthermore, the case 200 is provided with mounting tabs 240 on the upper part of the outer wall surface of the left side surface 204 and the right side surface 205 and the central part of the outer wall surface of the bottom surface 201. Each attachment tab 240 is formed with an insertion hole 241. A metal collar 242 is fitted into the insertion hole 241 in order to increase the strength of the hole. In addition, a positioning protrusion 243 that protrudes rearward is formed on the attachment tab 240 of the right side surface 205 and the bottom surface 201. When the film capacitor 1 is installed in an installation unit such as an external device, the mounting tabs 240 are fixed to the installation unit with screws or the like.

As shown in FIGS. 5 and 6, in the case 200, the inner wall surfaces of the left side surface 204 and the right side surface 205 are provided with support columns 250 on the front side and the rear side, respectively. Two struts 250 on the left side surface 204 and a front strut 250 on the right side surface 205 extend from the end 201a of the bottom surface 201 toward the opening 200a. On the other hand, the support column 250 on the rear side of the right side surface 205 extends to the opening 200a side from the stepped portion 205a formed by expanding the upper portion of the right side surface 205 outward. A concave portion 251 that is recessed in a shape corresponding to the protrusion 713 of the insulating plate 700 is formed at the upper end portion of each column 250.

Further, in the case 200, the inner wall surface of the left side surface 204 is an area where the two columns 250 are not provided, specifically, between the two columns 250 and the rear column 250 and the rear side surface 203. A plurality of protrusions 260 are provided in a region between the two. Each protrusion 260 extends from the end 201a of the bottom surface 201 toward the opening 200a. Each protrusion 260 does not reach the opening surface of the case 200, and the upper end surface 261 thereof is positioned slightly lower than the opening surface. Similarly, on the inner wall surface of the right side surface 205, an area where the two support columns 250 are not provided, specifically, between the two support columns 250, below the rear support column 250, and on the rear support column 250 and the rear side. A plurality of protrusions 260 are provided in a region between the side surface 203. Some protrusions 260 extend from the end portion 201 a of the bottom surface 201 toward the opening 200 a, and the upper end surface 261 thereof is positioned slightly lower than the opening surface of the case 200. In the present embodiment, the upper end surface 261 of the protrusion 260 is a flat surface. However, the upper end surface 261 may be a curved surface.

The projections 260 are provided on the left side surface 204 and the right side surface 205 so as to have a predetermined interval in the front-rear direction. The width of the protrusions 260 is significantly smaller than the width of the support pillars 250. Therefore, a large number of protrusions 260 can be formed in the area where the two support pillars 250 are not provided on the left side surface 204 and the right side surface 205. Further, the height of the protrusion 260, that is, the protruding length from the left side surface 204 or the right side surface 205 is smaller than the protruding length from the left side surface 204 or the right side surface 205 of the support column 250. For this reason, by providing the protrusion 260, the size of the case 200 in the left-right direction does not increase.

When the capacitor element unit 100 is accommodated in the case 200, the four protrusions 713 of the insulating plate 700 are fitted into the four recesses 251 of the case 200 (see FIG. 1B). That is, the protrusion 713 and the recess 251 function as positioning portions, and the capacitor element unit 100, that is, the gap is formed between the capacitor element 400 and the protrusions 260 on the left side surface 204 and the right side surface 205 of the case 200. Capacitor element 400 is positioned with respect to case 200. Furthermore, the capacitor element unit 100 is supported from the bottom surface 201 side of the case 200 by the four support columns 250. A gap is generated between the two capacitor elements 400 and the bottom surface 201 of the case 200.

The molten filling resin 300 is injected through the opening 200a into the case 200 in which the capacitor element unit 100 is accommodated. At this time, the filling resin 300 easily flows to the bottom surface 201 side of the case 200 by flowing downward through the matching

openings

511, 611, 711. Filling resin 300 is filled between capacitor element 400 and protrusions 260 on left side surface 204 and right side surface 205 of case 200. The filling resin 300 is also filled between the two capacitor elements 400 and the bottom surface 201 of the case 200. The filling resin 300 is filled in the case 200 to a position higher than the position of the upper end surface 261 of the protrusion 260. That is, the filling resin 300 is also present on the upper end surface 261 of the protrusion 260.

When the filling of the filling resin 300 is completed, the case 200 is heated and the filling resin 300 in the case 200 is cured. Thus, the film capacitor 1 is completed.

As shown in FIG. 1A, the first front connection terminal portion 530 of the first bus bar 500 and the second front connection terminal portion 630 of the second bus bar 600 are led out from the opening 200 a on the upper surface of the case 200 to the outside. Extends forward. The connection part 531 of the first front connection terminal part 530 and the connection part 631 on the left side of the second front connection terminal part 630 are installed on the installation surface 211 of the first front terminal block 210 of the case 200. The attachment holes 532 and 632 of the

connection portions

531 and 631 are aligned with the nuts 212 of the first front terminal block 210. Further, the right connection portion 631 of the second front connection terminal portion 630 is installed on the installation surface 221 of the second front terminal block 220 of the case 200. The attachment hole 632 of the connection portion 631 is aligned with the nut 222 of the second front terminal block 220.

As shown in FIG. 1B, the first rear connection terminal portion 540 of the first bus bar 500 and the second rear connection terminal portion 640 of the second bus bar 600 are led out from the opening 200 a on the upper surface of the case 200 to the outside. Extends backward. The connection part 541 of the first rear connection terminal part 540 and the connection part 641 of the second rear connection terminal part 640 are installed on the installation surface 231 of the rear terminal block 230 of the case 200. The attachment holes 542 and 642 of the

connection portions

541 and 641 are aligned with the nuts 232 of the rear terminal block 230. In the second rear connection terminal portion 640, the claw 233 is fitted in the square hole 644 of the second rear connection terminal portion 640 and the lower end portion is fitted in the hook 234 on the left side surface of the rear terminal base 230. Thereby, the connection part 641 of the 2nd back connection terminal part 640 becomes difficult to remove | deviate from the installation surface 231 of the back terminal block 230. FIG.

When the film capacitor 1 is mounted on an external device, the external device side external terminal (corresponding to the connection portion 531 of the first front connection terminal portion 530 and the connection portion 631 on the left side of the second front connection terminal portion 630 respectively) Are connected to the nut 212 of the first front terminal block 210 by screws. Further, a corresponding external terminal (not shown) on the external device side is connected to the right side connection portion 631 of the second front connection terminal portion 630 by screwing to the nut 222 of the second front terminal block 220. . Further, the external terminal on the external device side corresponding to each of the connection part 541 of the first rear connection terminal part 540 and the connection part 641 of the second rear connection terminal part 640 is screwed to the nut 232 of the rear terminal block 230. Connected by

FIG. 7 is a partially enlarged plan view in which the central portion of the left side surface 204 of the case 200 filled with the filling resin 300 according to the present embodiment is enlarged. In FIG. 6, the capacitor element unit 100 is not shown for convenience.

The material of the case 200 is PPS, and the material of the filling resin 300 is an epoxy resin. Therefore, the case 200 and the filling resin 300 have different linear expansion coefficients (thermal expansion coefficients). For example, the linear expansion coefficient of PPS is 4.0 to 4.9 × 10 ⁻⁵ / ° C., and the linear expansion coefficient of epoxy resin is 4.5 to 6.5 × 10 ⁻⁵ / ° C.

For this reason, when the film capacitor 1 is exposed to a high temperature environment or a low temperature environment, the case 200 and the filling resin 300 are caused by a difference in expansion / contraction ratio due to a difference in linear expansion coefficient between the case 200 and the filling resin 300. Stress may be generated at the interface portion of the surface to separate them. In particular, the case 200 has a longitudinal direction in the left-right direction, and the expansion / contraction ratio between the case 200 and the filling resin 300 in this direction is high. Therefore, the interface portion between the left side surface 204 and the filling resin 300 and the right side surface 205 and the filling resin 300 Stress tends to increase at the interface part.

In the present embodiment, at the interface between the left side surface 204 of the case 200 and the filling resin 300, as shown in FIG. 7, the filling resin 300 is the surface of the protrusion 260 provided on the left side surface 204, that is, the upper end surface. 261, the side surfaces 262 on both sides, and the front surface 263, and the contact area with the case 200 is increased by the amount corresponding to the upper end surface 261 and the side surfaces 262 on both sides, compared to the case where the protrusions 260 do not exist. As a result, the adhesion between the left side surface 204 and the filling resin 300 is enhanced, and when a stress is generated that causes the left side surface 204 and the filling resin 300 to be separated as indicated by the arrows in FIG. Since the force is increased, cracks and separation are less likely to occur between the left side surface 204 and the filling resin 300.

In particular, when a crack or peeling occurs on the casting surface portion of the filling resin 300, that is, on the surface exposed to the outside, the crack or peeling tends to proceed toward the bottom surface 201 side of the case 200 from that point. Become. However, in the present embodiment, the filling resin 300 is filled up to a position higher than the upper end surface 261 of the protrusion 260, and this portion is only the side surfaces 262 on both sides of the protrusion 260 in the casting surface portion of the filling resin 300. In addition, the contact with the upper end surface 261 strengthens the adhesion. For this reason, cracks and peeling are less likely to occur at the casting surface portion of the filling resin 300, and the progress of cracks and peeling toward the bottom surface 201 side of the case 200, which is the starting point, can be suppressed.

Similarly, even at the interface portion between the right side surface 205 of the case 200 and the filling resin 300, the protrusion 260 provided on the right side surface 205 makes it difficult for cracks and separation between the right side surface 205 and the filling resin 300 to occur.

Since the case 200 has a short direction in the front-rear direction, and the expansion ratio of the case 200 and the filling resin 300 in this direction is low, the interface portion between the front side surface 202 and the filling resin 300 and the rear side surface 203 and the filling resin 300 The stress at the interface is small, and cracking and peeling are unlikely to occur. Further, when the protrusions 260 are provided on the front side surface 202 and the rear side surface 203, the structure of the case 200 may be complicated, and the size of the case 200 in the front-rear direction may be increased. Therefore, in the present embodiment, the protrusions 260 are not formed on the inner wall surfaces of the front side surface 202 and the rear side surface 203 of the case 200. However, when priority is given to preventing cracks and peeling between the case 200 and the filling resin 300, the front side 202 and the rear side 203 may be provided with protrusions 260.

<Effect of Embodiment>
As described above, according to the present embodiment, the following effects are exhibited.

Since the protrusions 260 extending from the bottom surface 201 side of the case 200 to the opening 200a side are provided on the left side surface 204 and the right side surface 205 in the case 200, the space between the left side surface 204 and the right side surface 205 and the filling resin 300 is provided. Adhesion is enhanced, and cracks and peeling are less likely to occur between the case 200 (the left side surface 204 and the right side surface 205) and the filling resin 300. In addition, since the filling resin 300 is filled into the case 200 up to a position higher than the upper end surface 261 of the protrusion 260, the adhesion becomes strong at the portion of the casting surface of the filling resin 300. As a result, cracks and peeling are less likely to occur at the casting surface portion of the filling resin 300, and the progress of cracks and peeling toward the bottom surface 201 of the case 200, which is the starting point, can be suppressed.

In addition, although there is a possibility that cracks or peeling between the case 200 and the filling resin 300 may occur due to impact, vibration, or the like on the film capacitor 1, it is possible to suppress cracks or peeling due to such shock, vibration, or the like. It becomes.

Further, since the bottom surface 201 of the case 200 has a curved shape on both the left side surface 204 and the right side surface 205 where the protrusions 260 are formed, both cracks and peeling progress toward the bottom surface 201 side of the case 200. Even if something happens, it is easy to stop at the end 201a, and it is difficult for cracks and peeling to progress further to the bottom surface 201 side.

Further, the capacitor element unit 100, that is, the capacitor element 400 is positioned with respect to the case 200 so that a gap is formed between the capacitor element 400 and the protrusion 260 by the protrusion 713 serving as the positioning portion and the recess 251. Therefore, the filling resin 300 can be reliably filled between the protrusion 260 and the capacitor element 400, and the filling resin 300 can be securely adhered to the protrusion 260.

Further, since the plurality of protrusions 260 are provided in the area where the column 250 supporting the capacitor element unit 100 is not provided on the left side 204 and the right side 205, the left side is obtained using the area where the column 250 is not provided. 204 and the right side surface 205 and the filling resin 300 can be improved in adhesion, and cracks and peeling between the case 200 and the filling resin 300 can be suppressed. In addition, each protrusion 260 has a shorter protrusion length from the left side surface 204 and the right side surface 205 than the support column 250, so that it is possible to make it difficult for the case 200 to increase the size of the case 200 in the left-right direction.

The embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment, and the application example of the present invention can be modified in various ways in addition to the above embodiment. Is possible.

<Modification 1>
FIG. 8 is a cross-sectional perspective view of the left end portion of the case 200 according to the first modification.

In this modification, the lower end surface 264 corresponds to the “end surface on the bottom surface side” described in the claims.

In the film capacitor 1 of this modification, the lower end of the protrusion 260 does not extend to the end 201 a of the bottom surface 201 of the case 200 on the left side surface 204 of the case 200, and the lower end surface 264 of the protrusion 260 and the bottom surface 201 of the case 200. A gap is provided between the two. The protrusion 260 on the right side surface 205 of the case 200 has the same configuration as the protrusion 260 on the left side surface 204. In the present modification, the lower end surface 264 of the protrusion 260 is a flat surface. However, the lower end surface 264 may be a curved surface.

In the case of the configuration of this modified example, the filling resin 300 is filled also on the lower side of the lower end surface 264 of the protrusion 260, that is, the bottom surface 201 side. Therefore, in the lower part of the left side surface 204 and the right side surface 205, the filling resin 300 comes into contact with not only the side surfaces 262 on both sides of the protrusion 260 but also the lower end surface 264, thereby enhancing the adhesion. For this reason, the adhesiveness of the left side surface 204 and the right side surface 205 and the filling resin 300 further increases, and cracks and peeling can be further suppressed.

<Other changes>
In the above embodiment, each protrusion 260 on the left side surface 204 and the right side surface 205 can be extended to the lower end of the curved surface portion that is the end portion 201 a of the bottom surface 201.

Further, in the above embodiment, the width of the protrusion 260 is narrower than the interval between the two protrusions 260 arranged in the front-rear direction. However, the width of the protrusion 260 may be wider than the interval between the two protrusions 260.

Furthermore, in the above embodiment, the case 200 is formed in a rectangular parallelepiped box shape. However, the case 200 may be formed in any shape depending on the form of the capacitor element unit 100 as long as it has a bottom surface and side surfaces, and may be formed in a bottomed cylindrical shape, for example.

Furthermore, in the above embodiment, the positioning portion is configured by the protrusion 713 provided on the insulating plate 700 and the recess 251 provided on the support column 250. However, the configuration of the positioning portion is not limited to the above configuration, and may be other configurations as long as the capacitor element unit 100 is positioned with respect to the case 200.

Furthermore, in the above embodiment, the support column 250 is provided on the left side surface 204 and the right side surface 205 of the case 200. However, the support columns 250 may not be provided on the left side surface 204 and the right side surface 205. In this case, a plurality of protrusions 260 may be provided over the entire left side surface 204 and right side surface 205.

Furthermore, in the above embodiment, the capacitor element unit 100 includes two capacitor elements 400. However, the number of capacitor elements 400 can be changed as appropriate including the case where the number is one.

Furthermore, in the above embodiment, the capacitor element 400 is formed by stacking two metallized films obtained by vapor-depositing aluminum on a dielectric film, and winding or laminating the stacked metallized films. In addition, the capacitor element 400 may be formed by stacking a metallized film in which aluminum is vapor-deposited on both sides of the dielectric film and an insulating film, and winding or laminating them.

Furthermore, in the said embodiment, the film capacitor 1 was mentioned as an example of the capacitor | condenser of this invention. However, the present invention can also be applied to capacitors other than the film capacitor 1.

In addition, the embodiment of the present invention can be variously modified as appropriate within the scope of the technical idea shown in the claims.

In the description of the above embodiment, the terms indicating directions such as “upward” and “downward” indicate relative directions that depend only on the relative positional relationship of the constituent members, and include vertical and horizontal directions. It does not indicate the absolute direction.

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

1 Film capacitor (capacitor)
100 Capacitor element unit 200 Case 200a Opening 201 Bottom surface 204 Left side surface (side surface)
205 Right side (side)
250 support 251 recess (positioning part)
260 Protrusion 261 Upper end surface (end surface on the opening side)
H.264 Lower end surface (end surface on the bottom side)
300 Filling resin 400 Capacitor element 500 First bus bar (bus bar)
600 Second bus bar (bus bar)
700 Insulating plate 713 Projection (positioning part)

Claims

A capacitor element;
A case in which the capacitor element is accommodated;
A protrusion provided on a side surface in the case and extending from a bottom surface side to the opening side of the case;
A filling resin filled in the case,
The filling resin is filled in the case up to a position higher than the end surface of the case on the opening side of the protrusion,
A capacitor comprising:
The capacitor of claim 1,
The case and the filling resin have different linear expansion coefficients,
Capacitor characterized by that.
The capacitor according to claim 1 or 2,
A gap is provided between the end surface of the bottom surface of the case in the protrusion and the bottom surface of the case.
Capacitor characterized by that.
The capacitor according to any one of claims 1 to 3,
The bottom surface of the case has a curved shape at the end connected to the side surface of the case where the protrusion is formed.
Capacitor characterized by that.
The capacitor according to any one of claims 1 to 4,
A positioning portion for positioning the capacitor element with respect to the case so as to form a gap between the capacitor element and the protrusion;
Capacitor characterized by that.
The capacitor according to any one of claims 1 to 5,
Including the capacitor element and a bus bar connected to the capacitor element, and a capacitor element unit housed in the case;
A support provided on a side surface in the case, and supporting the capacitor element unit from the bottom surface side,
A plurality of the protrusions are provided in a region of the side surface in the case where the support column is not provided, and the protrusion length from the side surface in the case is smaller than the support column,
Capacitor characterized by that.