JP5045343B2 - Capacitor - Google Patents

Description

  The present invention relates to a capacitor in which a capacitor element is housed in a case and filled with resin.

  A capacitor for a filter or a snubber capacitor used in a power converter or the like is required to have a large capacity. As shown in FIGS. 7 and 8, as a capacitor that meets such a demand, a plurality of capacitor elements 51 are connected by a pair of metal electrode plates 52 and 53 made of copper or the like and housed in a case 54, and resin 55 (For example, refer to Patent Document 1).

JP 2006-245710 A

  However, in a filter capacitor or a snubber capacitor connected to an IGBT or the like, it is necessary to reduce the inductance as much as possible in order to reduce the switching loss. The situation is hard to say.

  In addition, since the capacitor as described above is formed by bending a plurality of electrode plates, not only the structure of the capacitor body is complicated, but also a metal electrode plate is attached to the electrode portions of the plurality of capacitor elements. When connecting, it is necessary to perform soldering to the metal electrode plate for every electrode portion of each capacitor element, and thus it cannot be said that the workability is good.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a capacitor that can solve the above-described problems, reduce the inductance, and can be easily manufactured with a simple structure.

In order to solve the above problems, the capacitor of the present invention includes an electrode portion 11 on both end surfaces, and a plurality of capacitor elements 2 that will be accommodated in the case 1, via an insulator 5 in case the opening 7 side have a first electrode plate 3 and the second electrode plate 4 that is superimposed, connect one of the electrodes 11 on the same side in the capacitor element 2 adjacent to the first electrode plate 3 through the lead wires 9 The other electrode part 11 on the same surface side in the adjacent capacitor element 2 is connected to the second electrode plate 4 via the lead wire 9 and the electrode parts 11 facing each other are arranged so as to have the same potential. A capacitor in which a resin 6 is filled in a case 1, and grooves 26 and 36 are arranged around lead wire connection holes 23 and 33 provided in the first electrode plate 3 and the second electrode plate 4. It is characterized by.

The grooves 26 and 36 are discontinuously arranged around the lead wire connection holes 23 and 33 in a substantially annular shape.

Further, the lead wire 9 is inserted into lead wire connection holes 23 and 33 provided in the first electrode plate 3 and the second electrode plate 4, and connected to the first electrode plate 3 and the second electrode plate 4. Is done.

Furthermore, the lead wire 9 is connected to the electrode portion 11 of the capacitor element 2 by welding.

According to the capacitor of the present invention, there are electrode portions on both end faces, the capacitor elements housed in the case are overlapped via the insulator on the case opening side, and are connected to the electrode portions of the capacitor element. In addition, since the capacitor has the first electrode plate and the second electrode plate, each electrode plate can be obtained by overlapping the entire surface of the electrode plate while having a simple structure in which the first electrode plate and the second electrode plate are simply stacked. It is possible to reduce the inductance by maximizing the effect of canceling out the magnetic flux generated in the magnetic field. In the capacitor of the present invention, the two electrode plates are formed in a flat plate shape. As in the prior art, the connecting terminal portion with the electrode portion of the capacitor element is integrally formed and bent. Since it is not necessary, the amount of the electrode plate used can be reduced.

  Furthermore, since the lead wire is inserted into the lead wire connection hole provided in the first electrode plate and the second electrode plate and connected to the first electrode plate and the second electrode plate, soldering or welding to the electrode plate As a result, the workability can be improved, and the soldering or welding process can be automated.

  Further, since the lead wire is connected to the electrode portion of the capacitor element by welding, the damage to the capacitor element is reduced, and the current resistance can be improved.

  Further, since the grooves are provided around the lead wire connection holes provided in the first electrode plate and the second electrode plate, the heat of the soldering iron in the soldering is not distributed to each electrode plate, It becomes possible to concentrate locally and to improve solderability.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The capacitor according to an embodiment of the present invention, as shown in FIGS. 1 and 2 has a first electrode plate 3 superimposed via an insulator 5 and the second electrode plate 4, these electrode plates 3 4, a plurality of capacitor elements 2 are connected, and the capacitor elements 2 are accommodated in the case 1, and the resin 1 is filled and cured in the case 1.

  As shown in FIG. 1, the case 1 is of a box shape, has a bottom portion and side portions, and has a case opening 7 that opens upward.

As shown in FIG. 1, the capacitor element 2 is provided with electrode portions 11 on both end faces. As shown in FIG. 6, this capacitor element 2 forms a capacitor element array by arranging four capacitor elements 2 in parallel with the electrode portions 11, 11 adjacent to each other facing each other in the lateral direction. In the state where three capacitor element rows are arranged in parallel in the vertical direction, they are arranged on the same surface on the bottom 8 side of the case 1. In the capacitor element rows adjacent to each other, the electrode parts 11 and 11 of the capacitor elements 2 adjacent in the vertical direction are arranged so as to be adjacent to each other on substantially the same plane, and these electrode parts 11 are at the same potential.

As shown in FIGS. 3 and 5, the first electrode plate 3 includes a flat plate-like main body portion 21 made of a metal plate, a terminal portion 22 protruding from the main body portion 21 and bent into a substantially L shape. Consists of. The main body portion 21 of the first electrode plate 3 is provided with a lead wire connecting hole 23 having a substantially elliptical shape, a lead wire escape hole 24 having a larger dimension, and a resin filling hole 25. Yes. Around the lead wire connection hole 23, a plurality of grooves 26 for concentrating heat in soldering locally are disposed discontinuously and in a substantially annular shape. The lead wire connection holes 23 and the lead wire escape holes 24 are arranged in a total of five horizontal rows, and the lead wire connection holes 23 are arranged at substantially equal intervals at substantially the center and both ends of the main body 21. The escape holes 24 are arranged at substantially equal intervals between the lead wire connection holes 23. Further, the resin filling hole 25 is placed next four rows between the lead wire connection hole 2 3 and the lead wire escape hole 24. In addition, the lead wire escape holes 24 and 24 in the edge part on the opposite side to the terminal part 22 of the 1st electrode plate 3 are notched and formed.

As shown in FIG. 4, the second electrode plate 4 is formed to be narrower than the first electrode plate 3, and is provided with a flat plate-like main body portion 31 made of a metal plate, and protrudes from the main body portion 31. Terminal portion 32 bent in a shape. The main body 31 of the second electrode plate 4 is provided with a long hole-like lead wire connection hole 33 having a substantially elliptical shape, a lead wire escape hole 34 having a larger dimension, and a resin filling hole 35. Yes. Around the lead wire connection hole 33, a plurality of grooves 36 for concentrating heat in soldering locally are disposed discontinuously and in a substantially annular shape. The lead wire connection holes 33 and the lead wire escape holes 34 are arranged in a total of three horizontal rows, and the lead wire escape holes 34 are arranged at substantially equal intervals in the main body 31, and the lead wire connection holes 33. Are arranged on both sides of the lead wire escape hole 34. Further, the resin filling holes 35 are arranged in four horizontal rows between the lead wire connection holes 33 and the lead wire escape holes 34 and at the end portions. In addition, the lead wire escape hole 34 in the edge part on the opposite side to the terminal part 32 of the 2nd electrode board 4 is notched and formed. A total of eight resin filling holes 35 are provided at substantially the same position as the first electrode plate 3 .

As shown in FIGS. 1, 2, and 5, the insulator 5 is formed wider than the second electrode plate 4, and is a sheet-like insulating paper having heat resistance and insulation properties that can withstand soldering work of lead wires. Consists of. Similar to the first electrode plate 3 and the second electrode plate 4, the insulating paper is also provided with a substantially elliptic lead wire escape hole 42 and a resin filling hole 43 . Hole 42 relief lead wire is arranged in three horizontal rows, the resin charging hole 43 is placed next four rows to the ends of and between the insulating paper of the hole 42 relief lead wire. A total of eight resin filling holes 43 are provided at substantially the same position as the second electrode plate 4. The insulator 5 may not be insulating paper.

  The first electrode plate 3, the second electrode plate 4, and the insulator 5 configured as described above have the insulator 5 interposed between the first electrode plate 3 and the second electrode plate 4, so that the second electrode The plates 4 are superposed with the plate 4 facing the case opening 7 side. The first electrode plate 3 is formed wider than the second electrode plate 4, and the first electrode plate 3 is placed at the end of the first electrode plate 3 in a state where the first electrode plate 3 and the second electrode plate 4 are overlapped. A certain lead wire connection hole 23 and a part of the groove 26 are exposed. Further, the lead wire connection hole 23 of the first electrode plate 3 and the lead wire escape hole 34 of the second electrode plate 4 are substantially in the same position, and the lead wire escape hole 24 of the first electrode plate 3 and the first electrode plate 3 The two electrode plates 4 are superposed so that the positions of the lead wire connection holes 33 are substantially the same, and the positions of the resin filling holes 25, 35, 43 of the electrode plates 3, 4 and the insulator 5 are substantially the same. In this way, they are superimposed. The lead wire connection holes 23 and 33 are electrically connected to the capacitor element 2 via the lead wires 9. At this time, the adjacent capacitor elements 2 are connected so that the electrode portions 11 on the same plane side have the same potential, and the adjacent capacitor elements 2 have the electrode portions 11 facing each other at the same potential. Since the lead wire connection holes 23 and 33 and the lead wire escape holes 24 and 34 of the electrode plates 3 and 4 are arranged so as to overlap each other as described above, the lead wire escape holes 24 and 34 are The dimensions are determined in consideration of solderability and insulation distance.

The lead wire 9 is formed of a stranded wire, CP wire, copper foil or the like, one end is connected to the electrode portion 11 of the capacitor element 2 by spot welding, and the other end is connected to the first electrode plate 3 by soldering or the like. . As described above, spot welding of the lead wire 9 causes less damage to the capacitor element 2 and improves current resistance compared to soldering. Further, in the figure, two lead wires 9 are connected to each electrode portion 11 of the capacitor element 2, but the number of arrangement can be changed according to the capacity of the capacitor element 2. As shown in FIG. 5, when the lead wires 9 and 9 are inserted into the lead wire connection holes 23 and 33 , the polarities of the adjacent capacitor elements 2 are the same, and the lead wires 9 can be in close contact with each other. Therefore, space can be saved.

  The plurality of capacitor elements 2, the first electrode plate 3, the second electrode plate 4, and the insulator 5 connected via the lead wires 9 are arranged so that the second electrode plate 4 is on the case opening 7 side. The capacitor can be obtained by storing the resin 6 and filling and curing the resin 6 with the terminal portions 22 and 32 of the first electrode plate 3 and the second electrode plate 4 exposed. In a state where the resin 6 is cured, the resin filling hole is also filled with the resin 6, so that the electrode plates 3 and 4 are restrained by the resin 6, and as a result, heat shock resistance can be improved.

  Therefore, in the capacitor configured as described above, the insulator 5 is provided between the first electrode plate 3 and the second electrode plate 4 while having a simple structure in which the first electrode plate 3 and the second electrode plate 4 are simply overlapped. By interposing them and keeping them in contact with each other while maintaining insulation, the magnetic fluxes generated in the electrode plates 3 and 4 can be canceled out, and the inductance can be reduced. In addition, the wiring length becomes the shortest and the electrode plates 3 and 4 have a simple configuration, so that the cost can be reduced. Furthermore, since the operation of connecting the lead wire 9 to each electrode plate 3 and 4 can be performed from one side (opening 7 side), the connection workability is improved and automation is easy.

  In addition, this invention is not limited to the said embodiment, Of course, many changes and corrections can be added within the scope of this invention. For example, the capacitor element may be configured using a wound capacitor, a multilayer capacitor, or the like.

It is a section side view showing an embodiment of a capacitor of this invention. It is a front view of the said capacitor | condenser. It is a front view which shows the 1st electrode plate of the said capacitor | condenser. It is a front view which similarly shows a 2nd electrode plate. It is the elements on larger scale which similarly show a through-hole. It is a front view which similarly shows the arrangement | sequence state of a capacitor | condenser element. It is a cross-sectional side view of a conventional capacitor. It is a front view of the conventional capacitor | condenser.

Explanation of symbols

  1 .. Case 2.. Capacitor element 3.. First electrode plate 4.. Second electrode plate 5.. Insulator, 6 .. Resin, 7 .. Case opening, 8. , 9 .. Lead wire, 11 .. Electrode section, 23, 33 .. Lead wire connection hole, 26, 36.

Claims (4)

It has electrode portions on both end faces (11), a case (1) a plurality of capacitor elements that will be housed (2) in, first in case opening (7) side that stacked via an insulator (5) possess first electrode plate (3) and the second electrode plate and (4), one electrode portion on the same side with the adjacent capacitor element (2) (11) via the first lead wire (9) Connected to the electrode plate (3) and connected to the second electrode plate (4) via the lead wire (9) the other electrode portion (11) on the same surface side in the adjacent capacitor element (2), A capacitor in which the electrode portions (11) facing each other are arranged at the same potential and the case (1) is filled with the resin (6) , the first electrode plate (3) and the second electrode plate ( Japanese a groove (26) (36) is arranged around the to provided the lead wire connection hole 4) (23) (33) Capacitors to be. The capacitor according to claim 1, wherein the groove (26) (36) is discontinuously and substantially annularly arranged around the lead wire connection hole (23) (33) . The lead wire (9) is inserted into lead wire connection holes (23) (33) provided in the first electrode plate (3) and the second electrode plate (4), and the first electrode plate (3). The capacitor according to claim 1, wherein the capacitor is connected to the second electrode plate (4) . The said lead wire (9) is a capacitor | condenser in any one of Claim 1 thru | or 3 connected by welding to the electrode part (11) of the said capacitor | condenser element (2) .