JP7630107B2 - Capacitor - Google Patents

Description

The present invention relates to a capacitor.

Conventionally, there is known a capacitor in which a capacitor element connected to one end of a bus bar is housed in a case, and a terminal for external connection provided at the other end of the bus bar is pulled out from an opening in the case (see, for example, Patent Document 1). An external terminal extending from an external device is connected to the terminal for external connection.

JP 2009-252935 A

In a configuration in which the terminals for external connection are located near the opening of the case, as in conventional capacitors, most of the busbar is inside the case. In such a configuration, if the external terminals generate heat and that heat is transferred to the busbar, or if the busbar itself generates heat, the heat is difficult to dissipate in the busbar and is likely to be transferred directly to the capacitor element, raising concerns that the capacitor element may be thermally damaged.

In view of these problems, the present invention aims to provide a capacitor whose capacitor elements are less susceptible to thermal damage.

A capacitor according to a main aspect of the present invention includes a capacitor element having a first electrode and a second electrode, a first bus bar and a second bus bar connected to the first electrode and the second electrode, respectively, and a case in which the capacitor element is housed . Here, the first bus bar and the second bus bar each have a first connection terminal portion , an electrode connection portion connected to a corresponding one of the first electrode and the second electrode, a second connection terminal portion provided between the first connection terminal portion and the electrode connection portion, and a relay terminal portion provided between the first connection terminal portion and the second connection terminal portion. The first connection terminal portion, the relay terminal portion, and the second connection terminal portion are arranged outside the case. The relay terminal portion of the first bus bar and the relay terminal portion of the second bus bar have portions that are aligned along a side portion of the case outside the case and overlap each other.

The present invention provides a capacitor that is less susceptible to thermal damage to the capacitor element.

The effects and significance of the present invention will become clearer from the description of the embodiment shown below. However, the embodiment shown below is merely an example of how the present invention can be put into practice, and the present invention is in no way limited to the embodiment described below.

FIG. 1 is a perspective view of a film capacitor according to an embodiment. FIG. 2 is an exploded perspective view of the film capacitor according to the embodiment. 3(a) and (b) are perspective views of a first inner member and a first outer member, respectively, according to an embodiment. 4(a) and (b) are perspective views of a second inner member and a second outer member, respectively, according to an embodiment. FIG. 5 is a diagram illustrating a state in which the film capacitor according to the embodiment is connected to an inverter device and a power supply device. FIG. 6 is a perspective view of a film capacitor according to a modified example.

The film capacitor 1, which is one embodiment of the 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 the relative directions of the film capacitor 1, and do not indicate absolute directions. Also, for convenience of explanation, some configurations may be given names that correspond to the directions shown in the drawings, such as the "bottom portion" and the "front side portion."

In this embodiment, the film capacitor 1 corresponds to the "capacitor" described in the claims. The inverter device 2 corresponds to the "semiconductor device" described in the claims. The first end electrode 110 corresponds to the "first electrode" described in the claims, and the second end electrode 120 corresponds to the "second electrode" described in the claims. The first inner member 200a and the second inner member 300a correspond to the "second member" described in the claims. The first outer member 200b and the second outer member 300b correspond to the "first member" described in the claims. The inner connection terminals 220 and 320 correspond to the "second connection terminal" described in the claims. The outer connection terminals 230 and 330 correspond to the "first connection terminal" described in the claims. The relay terminals 240 and 340 correspond to the "exposed portion" described in the claims. The front side portion 402 corresponds to the "side portion" described in the claims. Furthermore, the second insulating sheet 700 corresponds to the "insulating member" described in the claims.

However, the above description is intended only to correlate the configuration of the claims with the configuration of the embodiments, and the above correlation does not in any way limit the invention described in the claims to the configuration of the embodiments.

Figure 1 is a perspective view of a film capacitor 1. Figure 2 is an exploded perspective view of the film capacitor 1.

The film capacitor 1 comprises four capacitor elements 100, a first bus bar 200, a second bus bar 300, a case 400, and a filling resin 500. The first bus bar 200 is composed of a first inner member 200a and a first outer member 200b, and the second bus bar 300 is composed of a second inner member 300a and a second outer member 300b.

The four capacitor elements 100, the first inner member 200a, and the second inner member 300a are assembled together and housed in the case 400. The filled resin 500 is a thermosetting resin, for example, an epoxy resin, and is filled into the case 400. The four capacitor elements 100 and most of the first inner member 200a and the second inner member 300a are embedded in the filled resin 500, and are protected from moisture and impact by the case 400 and the filled resin 500.

The first outer member 200b and the second outer member 300b are combined and attached to the front of the case 400. This connects the first inner member 200a and the first outer member 200b at the first bus bar 200, and connects the second inner member 300a and the second outer member 300b at the second bus bar 300.

The film capacitor 1 is described in detail below.

Referring to FIG. 2, the capacitor element 100 is formed by stacking two metallized films in which aluminum is vapor-deposited on a dielectric film, rolling or laminating the stacked metallized films, and pressing them into a flat shape. The capacitor element 100 has a shape similar to a flat oval cylinder. The capacitor element 100 has a first end surface electrode 110 formed by spraying a metal such as zinc on one end surface 101, and a second end surface electrode 120 formed by spraying a metal such as zinc on the other end surface 102. The four capacitor elements 100 are arranged in two rows, two on each row, with both end surfaces 101 and 102 facing the front-rear direction. In this state, the first inner member 200a of the first bus bar 200 and the second inner member 300a of the second bus bar 300 are connected to these capacitor elements 100.

In the present embodiment, the capacitor element 100 is formed from a metallized film in which aluminum is vapor-deposited onto a dielectric film, but it may also be formed from a metallized film in which other metals, such as zinc or magnesium, are vapor-deposited. Alternatively, the capacitor element 100 may be formed from a metallized film in which multiple of these metals are vapor-deposited, or from a metallized film in which an alloy of these metals is vapor-deposited.

As described above, the first busbar 200 includes a first inner member 200a and a first outer member 200b.

Figures 3(a) and (b) are perspective views of the first inner member 200a and the first outer member 200b, respectively.

As shown in FIG. 3(a), the first inner member 200a is formed by appropriately cutting and bending a conductive material, such as a copper plate, and has a configuration in which an electrode terminal portion 210 and three inner connection terminal portions 220 are integrated together.

The electrode terminal portion 210 includes a side portion 211 and a top portion 212 that bends vertically backward from the upper end of the side portion 211. The side portion 211 has a rectangular shape with the lower right corner missing. The top portion 212 has a long and narrow rectangular shape, with the rear end 212a rising upward.

The electrode terminal portion 210 has four rectangular openings 213 aligned in the left-right direction formed at the top of the side portion 211, and a connection pin 214 is formed at the upper edge of each opening 213. The electrode terminal portion 210 also has four connection pins 214 aligned in the left-right direction formed at the lower end of the side portion 211. Furthermore, the electrode terminal portion 210 has a circulation opening 215 formed in the center in the left-right direction by cutting out the lower end of the side portion 211 in a semicircular shape, and a circulation opening 216 that is long vertically so as to straddle the side portion 211 and the upper surface portion 212.

The three inner connection terminals 220 are rectangular and extend upward from the upper end of the electrode terminal 210, i.e., the rear end 212a of the upper surface 212. The three inner connection terminals 220 are aligned at equal intervals in the left-right direction. A circular through hole 221 is formed in each inner connection terminal 220.

As shown in FIG. 3(b), the first outer member 200b is formed by appropriately cutting and bending a conductive material, such as a copper plate, and has a configuration in which the outer connection terminal portion 230 and the relay terminal portion 240 are integrated.

The outer connection terminal portion 230 has a rectangular shape. A circular through hole 231 is formed in the outer connection terminal portion 230.

The relay terminal portion 240 includes a terminal body portion 241, a first connecting portion 242, and three second connecting portions 243. The terminal body portion 241 has a hook shape with the right side bent downward. The upper right corner of the terminal body portion 241 is cut out in an arc shape to avoid the mounting boss (described later) of the case 400.

The first connecting portion 242 extends rightward from the lower right end of the terminal body 241, then bends and extends rearward, and connects to the outer connection terminal portion 230. The three second connecting portions 243 are provided at the upper end of the terminal body 241 so as to be aligned at equal intervals in the left-right direction. Each second connecting portion 243 extends upward, then bends and extends rearward, and then bends again, with its tip 243a extending upward. A circular through hole 244 is formed in the tip 243a of the second connecting portion 243. The left-right width of the tip 243a of the second connecting portion 243 and the inner diameter of the through hole 244 are made equal to the left-right width of the inner connection terminal portion 220 of the first inner member 200a and the inner diameter of the through hole 221.

The first connecting portion 242 extends to the terminal body 241 with the same width as the width (vertical width) W1 of the base end 230a connected to the first connecting portion 242 of the outer connection terminal portion 230, i.e., the relay terminal portion 240. On the other hand, the vertical width W2 of the terminal body 241 is not constant, being wider on the right side and narrower on the left side, but is wider than the width W1 of the base end 230a. Furthermore, the horizontal width W3 of the terminal body 241 is not constant, being narrower on the lower side and wider on the upper side, but is wider than the width W1 of the base end 230a. In other words, the terminal body 241 is not configured to extend leftward and upward with a width equal to the width W1 of the base end 230a of the outer connection terminal portion 230, as shown by the dashed line in FIG. 3(b), and a large area is ensured.

As described above, the second busbar 300 includes a second inner member 300a and a second outer member 300b.

Figures 4(a) and (b) are perspective views of the second inner member 300a and the second outer member 300b, respectively.

As shown in FIG. 4(a), the second inner member 300a is formed by appropriately cutting and bending a conductive material, such as a copper plate, and has a configuration in which an electrode terminal portion 310 and three inner connection terminal portions 320 are integrated together.

The electrode terminal portion 310 includes a side portion 311 and a top portion 312 that bends vertically forward from the upper end of the side portion 311. The side portion 311 has a rectangular shape with the lower right corner missing. The top portion 312 has a rectangular shape with its front end 312a rising upward.

The electrode terminal portion 310 has four rectangular openings 313 aligned in the left-right direction formed in the center of the side surface portion 311, and a connection pin 314 is formed at the upper edge of each opening 313. The electrode terminal portion 310 also has four connection pins 314 aligned in the left-right direction formed at the lower end of the side surface portion 311. The electrode terminal portion 310 also has a circular flow opening 315 and a vertically long flow opening 316 that spans the side surface portion 311 and the upper surface portion 312 formed in the center in the left-right direction.

The three inner connection terminals 320 are rectangular and extend upward from the upper end of the electrode terminal 310, i.e., the front end 312a of the upper surface 312. The three inner connection terminals 320 are aligned at equal intervals in the left-right direction. Each inner connection terminal 320 has a circular through hole 321 formed therein.

As shown in FIG. 4(b), the second outer member 300b is formed by appropriately cutting and bending a conductive material, such as a copper plate, and has a configuration in which the outer connection terminal portion 330 and the relay terminal portion 340 are integrated.

The outer connection terminal portion 330 has a rectangular shape. A circular through hole 331 is formed in the outer connection terminal portion 330.

The relay terminal portion 340 includes a terminal body portion 341, a first connecting portion 342, and three second connecting portions 343. The terminal body portion 341 has a hook shape with the right side bent downward. The upper left corner and the upper right corner of the terminal body portion 341 are cut out in an arc shape and a square shape, respectively, to avoid the mounting boss (described later) of the case 400.

The first connecting portion 342 extends rightward from the lower right end of the terminal body 341, then bends and extends backward, and connects to the outer connection terminal portion 330. The three second connecting portions 343 are provided at the upper end of the terminal body 341 so as to be aligned at equal intervals in the left-right direction. Each second connecting portion 343 extends upward, then bends and extends backward, and then bends again, with its tip 343a extending upward. A circular through hole 344 is formed in the tip 343a of the second connecting portion 343. The left-right width of the tip 343a of the second connecting portion 343 and the inner diameter of the through hole 344 are made equal to the left-right width of the inner connection terminal portion 320 of the second inner member 300a and the inner diameter of the through hole 321.

The first connecting portion 342 extends to the terminal body 341 with the same width as the width (vertical width) W4 of the base end 330a connected to the first connecting portion 342 of the outer connection terminal portion 330, i.e., the relay terminal portion 340. On the other hand, the vertical width W5 of the terminal body 341 is not constant, being wider on the right side and narrower on the left side, but is wider than the width W4 of the base end 330a. Furthermore, the horizontal width W6 of the terminal body 341 is not constant, being narrower on the lower side and wider on the upper side, but is wider than the width W4 of the base end 330a. In other words, the terminal body 341 is not configured to extend leftward and upward with a width equal to the width W4 of the base end 330a of the outer connection terminal portion 330, as shown by the dashed line in FIG. 4(b), and a large area is ensured.

As shown in FIG. 2, the electrode terminal portion 210 of the first inner member 200a covers the first end surface electrodes 110 of the four capacitor elements 100 from the front, and the electrode terminal portion 310 of the second inner member 300a covers the second end surface electrodes 120 of the four capacitor elements 100 from the rear. Two connection pins 214 of the electrode terminal portion 210 contact the first end surface electrodes 110 of each capacitor element 100, and each connection pin 214 is joined to the corresponding first end surface electrodes 110 by a joining method such as soldering. Similarly, two connection pins 314 of the electrode terminal portion 310 contact the second end surface electrodes 120 of each capacitor element 100, and each connection pin 314 is joined to the corresponding second end surface electrodes 120 by a joining method such as soldering. As a result, the first bus bar 200 is electrically connected to the first end surface electrodes 110 of the four capacitor elements 100, and the second bus bar 300 is electrically connected to the second end surface electrodes 120 of the four capacitor elements 100.

When the four capacitor elements 100, the first inner member 200a, and the second inner member 300a are integrated, the three inner connection terminal portions 220 of the first inner member 200a and the three inner connection terminal portions 320 of the second inner member 300a are arranged alternately in the left-right direction.

The first insulating sheet 600 is sandwiched between the first inner member 200a and the second inner member 300a. The first insulating sheet 600 is formed from insulating paper or an electrically insulating resin material such as acrylic or silicone. The first insulating sheet 600 ensures an insulating distance between the first inner member 200a and the second inner member 300a, and an insulating distance between the second inner member 300a and the first end surface electrode 110 of the capacitor element 100, etc.

As also shown in FIG. 2, the first outer member 200b and the second outer member 300b are overlapped front to back so that their relay terminal portions 240, 340, i.e., the terminal body portions 241, 341, overlap each other via the second insulating sheet 700. The second insulating sheet 700 is formed from insulating paper or a resin material having electrical insulation properties, such as acrylic or silicone. The second insulating sheet 700 ensures an insulation distance between the two relay terminal portions 240, 340, etc.

The first outer member 200b and the second insulating sheet 700 are fixed with double-sided tape (not shown), and the second outer member 300b and the second insulating sheet 700 are fixed with double-sided tape (not shown). This fixes the first outer member 200b, the second outer member 300b, and the second insulating sheet 700 together.

When the first outer member 200b and the second outer member 300b are integrated, the three second connecting portions 243 of the first outer member 200b and the three second connecting portions 343 of the second outer member 300b are arranged alternately in the left-right direction. In addition, the outer connection terminal portion 230 of the first outer member 200b and the outer connection terminal portion 330 of the second outer member 300b are arranged in the up-down direction.

Referring to FIG. 2, case 400 is made of resin, for example, polyphenylene sulfide (PPS), which is a thermoplastic resin. Case 400 is formed in a substantially rectangular box shape, and has bottom portion 401, front side portion 402, rear side portion 403, left side portion 404, and right side portion 405 rising from bottom portion 401, and is open at the top. Case 400 has a longitudinal direction in the left-right direction in which two capacitor elements 100 are lined up in the upper and lower rows, and a lateral direction in which both end faces of four capacitor elements 100 face, which is the front-rear direction.

The case 400 has mounting tabs 410 at the top of the left side surface 404, the top of the right side surface 405, and the left and right ends of the bottom surface 401. Each mounting tab 410 has a through hole 411 formed therein. A metal collar 412 is fitted into the through hole 411 to increase the strength of the hole. These mounting tabs 410 are used when the film capacitor 1 is fixed to the installation portion of an external device such as an inverter device.

A first terminal block 420 and a second terminal block 430 are provided vertically connected below the mounting tab 410 on the right side surface 405 of the case 400. The upper first terminal block 420 is a terminal block for the outer connection terminal portion 230 of the first bus bar 200, and the lower second terminal block 430 is a terminal block for the outer connection terminal portion 330 of the second bus bar 300. The mounting surface 421 of the first terminal block 420 and the mounting surface 431 of the second terminal block 430 are separated by a rib 440.

A metal nut 422 is embedded in the mounting surface 421 of the first terminal block 420. A downward claw portion 423 is formed on the upper part of the mounting surface 421 of the first terminal block 420. A metal nut 432 is embedded in the mounting surface 431 of the second terminal block 430. A downward claw portion 433 is formed on the lower part of the mounting surface 431 of the second terminal block 430.

The front side surface 402 of the case 400 has mounting bosses 450 in a total of five locations: the center and the four corners. Metal nuts 451 are embedded in each mounting boss 450. In addition, the front side surface 402 of the case 400 has a right-facing claw portion 461 formed near the upper left corner, and an upward-facing claw portion 462 formed near the right end of the lower end.

A unit consisting of the four capacitor elements 100, the first inner member 200a, and the second inner member 300a is housed in the case 400 through the opening 400a on the top surface. Then, the filling resin 500 in a liquid phase is injected into the case 400. At this time, the filling resin 500 passes through the flow openings 215, 216 of the first inner member 200a and the flow openings 315, 316 of the second inner member 300a, so that the filling resin 500 easily reaches the portions of the four capacitor elements 100 inside the first inner member 200a and the second inner member 300a. When the filling resin 500 fills the case 400 up to the vicinity of the opening 400a and the injection of the filling resin 500 is completed, the case 400 is heated. This causes the filling resin 500 in the case 400 to harden.

Then, the unit consisting of the first outer member 200b and the second outer member 300b is attached to the case 400. At this time, the outer connection terminal portion 230 of the first outer member 200b is attached to the mounting surface 421 of the first terminal block 420, and the outer connection terminal portion 330 of the second outer member 300b is attached to the mounting surface 431 of the second terminal block 430. The through hole 231 of the outer connection terminal portion 230 is aligned with the nut 422 of the first terminal block 420, and the through hole 331 of the outer connection terminal portion 330 is aligned with the nut 432 of the second terminal block 430.

The terminal body 241 of the relay terminal 240 of the first outer member 200b and the terminal body 241 of the relay terminal 240 of the first outer member 200b are aligned along the front side portion 402 so that their surfaces face the front side portion 402. The two terminal body portions 241, 341 overlap each other on the front of the front side portion 402 via the second insulating sheet 700. In addition, the three second connecting portions 243 of the first outer member 200b are overlapped from the front onto the corresponding inner connection terminal portions 220 of the first inner member 200a, and the three second connecting portions 343 of the second outer member 300b are overlapped from the front onto the corresponding inner connection terminal portions 320 of the second inner member 300a. The through holes 244, 344 of each second connecting portion 243, 343 are aligned with the through holes 221, 321 of each inner connection terminal portion 220, 320.

The outer connection terminal portion 230 of the first outer member 200b engages with the claw portion 423 of the first terminal block 420, and the outer connection terminal portion 330 of the second outer member 300b engages with the claw portion 433 of the second terminal block 430. In addition, the terminal body portion 341 of the second outer member 300b engages with the two claw portions 461, 462 of the front side portion 402. This fixes the unit consisting of the first outer member 200b and the second outer member 300b to the case 400.

In this way, the film capacitor 1 is completed as shown in Figure 1.

The film capacitor 1 can be mounted, for example, in an inverter device for driving an electric motor in an electric vehicle.

Figure 5 is a schematic diagram showing the film capacitor 1 connected to an inverter device 2 and a power supply device 3.

The inverter device 2 is supplied with DC power from a power supply device 3 (battery). The inverter device 2 has an inverter circuit including IGBTs (insulated gate bipolar transistors), converts the DC power into three-phase AC power, and supplies it to an electric motor (not shown). In this way, the inverter device 2 is a semiconductor device (power semiconductor device) for converting power.

In the film capacitor 1, the outer connection terminal portion 230 of the first bus bar 200 is connected to the corresponding first external terminal 11, and is connected to the terminal 3a of the power supply device 3 having the same polarity as the outer connection terminal portion 230 through the first external terminal 11. The outer connection terminal portion 330 of the second bus bar 300 is connected to the corresponding first external terminal 12, and is connected to the terminal 3b of the power supply device 3 having the same polarity as the outer connection terminal portion 330 through the first external terminal 12. At this time, the outer connection terminal portion 230 of the first bus bar 200 and the first external terminal 11 are attached to the first terminal block 420 by screwing into the nut 422 in a state where they are overlapped. Similarly, the outer connection terminal portion 330 of the second bus bar 300 and the first external terminal 12 are attached to the second terminal block 430 by screwing into the nut 432 in a state where they are overlapped.

Furthermore, in the film capacitor 1, the three inner connection terminals 220 of the first bus bar 200 are connected to the corresponding second external terminals 13, and are connected to the terminals 2a of the inverter device 2 having the same polarity as the inner connection terminals 220 via the second external terminals 13. The three inner connection terminals 320 of the second bus bar 300 are connected to the corresponding second external terminals 14, and are connected to the terminals 2b of the inverter device 2 having the same polarity as the inner connection terminals 320 via the second external terminals 14. At this time, the inner connection terminals 220 of the first inner member 200a, the second connecting portion 243 of the first outer member 200b, and the second external terminals 13 are fastened and fixed by screws (not shown) and nuts (not shown). Similarly, the inner connection terminal portion 320 of the second inner member 300a, the second connecting portion 343 of the second outer member 300b, and the second external terminal 14 are fastened and fixed together with a screw (not shown) and a nut (not shown).

In this way, the connection between the inner connection terminal portion 220 and the second external terminal 13 and the fixing between the first inner member 200a and the first outer member 200b can be performed by fastening with a single screw. Similarly, the connection between the inner connection terminal portion 320 and the second external terminal 14 and the fixing between the second inner member 300a and the second outer member 300b can be performed by fastening with a single screw. This reduces the number of screws and the screw fastening process. In addition, it is no longer necessary to provide a connecting portion on the first inner member 200a and the second inner member 300a to connect them to the second connecting portions 243, 343.

When the electric motor is driven by the inverter device 2 and electricity is applied to the film capacitor 1, a large direct current from the power supply device 3 can flow through the relay terminal portion 240 that constitutes a path connecting the outer connection terminal portion 230 and the inner connection terminal portion 220 in the first bus bar 200. In addition, heat generated at the first external terminal 11 by the large direct current from the power supply device 3 can be transmitted to the relay terminal portion 240 via the outer connection terminal portion 230. Similarly, a large direct current from the power supply device 3 can flow through the relay terminal portion 340 that constitutes a path connecting the outer connection terminal portion 330 and the inner connection terminal portion 320 in the second bus bar 300. In addition, heat generated at the first external terminal 12 by the large direct current from the power supply device 3 can be transmitted to the relay terminal portion 340 via the outer connection terminal portion 330.

However, these relay terminals 240, 340 are exposed outside the case 400, particularly outside the filling resin 500. Furthermore, the terminal main bodies 241, 341 of these relay terminals 240, 340 are aligned along the front side surface 402 of the case 400, and as long as they do not protrude from the area of the front side surface 402, the size of the film capacitor 1 is unlikely to increase. For this reason, a large area is ensured for the terminal main bodies 241, 341 of the relay terminals 240, 340. Therefore, since the relay terminals 240, 340 have low electrical resistance and good heat dissipation properties, they are unlikely to generate heat even if a large current flows through them, and even if heat is transmitted to them, the heat is easily dissipated.

The terminal body portions 241, 341 of the relay terminal portions 240, 340 of the first bus bar 200 and the second bus bar 300 overlap each other in front of the front side portion 402 via the second insulating sheet 700. This reduces the ESL (equivalent series inductance).

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

The film capacitor 1 includes a first bus bar 200 and a second bus bar 300 arranged outside the case 400, outer connection terminal portions 230, 330 connectable to the first external terminals 11, 12, and relay terminal portions 240, 340 extending outside the case 400 and connecting to the outer connection terminal portions 230, 330, and the relay terminal portions 240, 340 are aligned along the front side portion 402 of the case 400 so that their surfaces face the front side portion 402.

According to this configuration, the relay terminals 240, 340 can secure a large area in the portion (terminal body portion 241, 341) along the front side portion 402 of the case 400, so that the electrical resistance is small and the heat dissipation is improved. Therefore, when a current flows through the relay terminals 240, 340, the relay terminals 240, 340 themselves are less likely to generate heat, and even if heat generated in the first external terminals 11, 12 is transmitted through the outer connection terminal portions 230, 330, the heat is easily dissipated by the relay terminals 240, 340. Therefore, the heat transmitted to the capacitor element 100 through the first bus bar 200 and the second bus bar 300 can be reduced, so that the capacitor element 100 is less likely to be damaged by heat.

In addition, the relay terminal portion 240 of the first bus bar 200 and the relay terminal portion 340 of the second bus bar 300 have portions that overlap each other via the second insulating sheet 700 on the front side of the front side portion 402.

This configuration allows for a reduction in ESL (equivalent series inductance).

The first bus bar 200 and the second bus bar 300 further include inner connection terminal portions 220, 320 that are exposed from the filled resin 500 and to which the second external terminals 13, 14 are connected. The outer connection terminal portions 230, 330 are connected to the power supply device 3 via the first external terminals 11, 12, and the inner connection terminal portions 220, 320 are connected to the inverter device 2 via the second external terminals 13, 14. The relay terminal portions 240, 340 form paths that connect the outer connection terminal portions 230, 330 and the inner connection terminal portions 220, 320.

With this configuration, even if a large current from the power supply device 3 flows through the relay terminals 240, 340, the relay terminals 240, 340 themselves are less likely to heat up. Also, even if the first external terminals 11, 12 generate heat due to the large current from the power supply device 3 and the heat is transmitted, the relay terminals 240, 340 can dissipate the heat well. Therefore, the heat caused by the large current from the power supply device 3 can be prevented from being transmitted to the capacitor element 100, making it less likely that thermal damage will occur to the capacitor element 100.

The first bus bar 200 further includes a first outer member 200b having a relay terminal portion 240 and an outer connection terminal portion 230, a first inner member 200a having a connection pin 214 embedded in the filled resin 500 and connected to the first end surface electrode 110, and an inner connection terminal portion 220, and is connected to the first outer member 200b. The second bus bar 300 further includes a second outer member 230b having a relay terminal portion 340 and an outer connection terminal portion 330, a connection pin 314 embedded in the filled resin 500 and connected to the second end surface electrode 120, and a second inner member 300a having an inner connection terminal portion 320, and is connected to the second outer member 300b.

According to the above configuration, after the unit formed by connecting the first inner member 200a and the second inner member 300a to the capacitor element 100 is housed in the case 400 and filled with the filling resin 500, the first outer member 200b and the second outer member 300b can be attached to the case 400, the first outer member 200b can be connected to the first inner member 200a, and the second outer member 300b can be connected to the second inner member 300a. This makes it possible to easily assemble the film capacitor 1.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications of the application examples of the present invention are possible in addition to the above embodiment.

For example, in the above embodiment, the first terminal block 420 to which the outer connection terminal portion 230 of the first bus bar 200 is attached and the second terminal block 430 to which the outer connection terminal portion 330 of the second bus bar 300 is attached are provided on the right side portion 405 different from the front side portion 402 to which the relay terminal portions 240, 340 of the first bus bar 200 and the second bus bar 300 are aligned. However, as shown in FIG. 6, the first terminal block 420 and the second terminal block 430 may be provided on the same front side portion 402 as the side portion to which the relay terminal portions 240, 340 are aligned, and the outer connection terminal portion 230 of the first bus bar 200 and the outer connection terminal portion 330 of the second bus bar 300 are attached to these terminal blocks 420, 430, respectively. In this case, in the relay terminal portion 240, 340, the first connecting portion 242, 342 extends downward from the lower end of the terminal body portion 241, 341, then bends and extends forward to connect to the outer connection terminal portion 230, 330. In addition, in the first terminal block 420 and the second terminal block 430, the upward claw portion 423, 433 engages with the attached outer connection terminal portion 230, 330.

The relay terminals 240, 340 of the first bus bar 200 and the second bus bar 300 may be arranged along a side surface of the case 400 other than the front side surface 402. In this case, it is desirable that the relay terminals 240, 340 are arranged along the rear side surface 403, which, like the front side surface 402, has a larger area than the left side surface 404 and the right side surface 405.

Furthermore, in the above embodiment, both the first bus bar 200 and the second bus bar 300 include relay terminal portions 240, 340 that are aligned with the front side portion 402 of the case 400. However, a configuration in which only the first bus bar 200 includes the relay terminal portion 240, or only the second bus bar 300 includes the relay terminal portion 340 may also be adopted.

Furthermore, in the above embodiment, the second connecting portion 243 of the first outer member 200b is connected to the inner connection terminal portion 220 of the first inner member 200a, and the second connecting portion 343 of the second outer member 300b is connected to the inner connection terminal portion 320 of the second inner member 300a. However, the second connecting portion 243 of the first outer member 200b may be connected to a connecting portion separately provided on the first inner member 200a, and the second connecting portion 343 of the second outer member 300b may be connected to a connecting portion separately provided on the second inner member 300a.

Furthermore, in the above embodiment, the first bus bar 200 is composed of two members, the first inner member 200a and the first outer member 200b, and the second bus bar 300 is composed of two members, the second inner member 300a and the second outer member 300b. However, the first bus bar 200 and the second bus bar 300 may be composed of a single member.

Furthermore, in the above embodiment, the film capacitor 1 is provided with four capacitor elements 100. However, the number of capacitor elements 100 can be changed as appropriate, including the case where there is only one.

Furthermore, in the above embodiment, the capacitor element 100 is formed by stacking two metallized films with aluminum vapor-deposited on a dielectric film, and then rolling or laminating the stacked metallized films. However, in addition to this, these capacitor elements 100 may also be formed by stacking a metallized film with aluminum vapor-deposited on both sides of a dielectric film and an insulating film, and then rolling or laminating the resulting structure.

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

In addition, various modifications of the embodiment of the present invention are possible within the scope of the technical ideas set forth in the claims.

In the above description of the 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 vertical or horizontal.

The present invention is useful for capacitors used in various electronic devices, electrical devices, industrial equipment, vehicle electrical equipment, etc.

1. Film capacitor (capacitor)
2. Inverter device (semiconductor device)
3 Power supply device 11 First external terminal 12 First external terminal 13 Second external terminal 14 Second external terminal 100 Capacitor element 110 First end electrode (first electrode)
120 Second end surface electrode (second electrode)
200 First bus bar 200a First inner member (second member)
200b First outer member (first member)
220 Inner connection terminal portion (second connection terminal portion)
230 Outer connection terminal portion (first connection terminal portion)
240 Relay terminal part (exposed part)
300 Second bus bar 300a Second inner member (second member)
300b Second outer member (first member)
320 Inner connection terminal portion (second connection terminal portion)
330 Outer connection terminal portion (first connection terminal portion)
340 Relay terminal part (exposed part)
400 Case 402 Front side part (side part)
500 Filling resin 700 Second insulating sheet (insulating member)

Claims (6)

a capacitor element having a first electrode and a second electrode;
a first bus bar and a second bus bar connected to the first electrode and the second electrode, respectively;
a case in which the capacitor element is housed ,
The first bus bar and the second bus bar each have
A first connection terminal portion;
an electrode connection portion connected to a corresponding one of the first electrode and the second electrode;
a second connection terminal portion provided between the first connection terminal portion and the electrode connection portion;
a relay terminal portion provided between the first connection terminal portion and the second connection terminal portion,
the first connection terminal portion, the relay terminal portion, and the second connection terminal portion are disposed outside the case,
the relay terminal portion of the first bus bar and the relay terminal portion of the second bus bar have portions that are aligned along a side surface of the case outside the case and overlap each other.
A capacitor characterized by: 2. The capacitor according to claim 1,
the first connection terminal portion is connected to a power supply device via a first external terminal,
The second connection terminal portion is connected to a semiconductor device via a second external terminal.
A capacitor characterized by: 2. The capacitor according to claim 1,
A filling resin is provided to fill the case,
The electrode connection portion is embedded in the filling resin .
A capacitor characterized by: The capacitor according to any one of claims 1 to 3 ,
the relay terminal portion of the first bus bar and the relay terminal portion of the second bus bar overlap each other via an insulating member.
A capacitor characterized by: The capacitor according to any one of claims 1 to 4 ,
The first bus bar and the second bus bar are
a first member having the first connection terminal portion and the relay terminal portion;
a second member having the electrode connection portion and the second connection terminal portion;
A capacitor characterized by: 6. The capacitor according to claim 5 ,
The first member has a plurality of connecting portions,
The second member includes a plurality of the second connection terminal portions,
The plurality of coupling portions are coupled to the plurality of second connection terminal portions, respectively.
A capacitor characterized by:

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