JP2006237032A - Capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capacitor in which filling resin is not cracked easily and durability against temperature variation is enhanced. <P>SOLUTION: A capacitor element 2 is contained in a case 1 which is then filled with resin to produce a capacitor. A member 15 for sectioning the resin surface at the opening 7 of the case 1 is provided such that a part thereof is buried in a resin layer 3 and other part projects from the resin surface. The section member 15 is composed of a planar body arranged such that the thickness direction T intersects the depth direction D of the case 1 substantially perpendicularly. End portion 20 of the planar body being buried in the resin layer 3 is rounded. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

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

Capacitors and snubber capacitors used in inverter devices are required to have a large capacity. For this reason, as a capacitor used in an inverter device or the like, a capacitor in which a plurality of capacitor elements are connected by a pair of metal electrode bus bars made of copper or the like and housed in a case and filled and cured with resin may be used (for example, , See Patent Document 1). In this case, it is often the case that the opening of the case is made large in consideration of the process of incorporating the capacitor element into the case.
JP 2003-133172 A

  By the way, inverter devices such as in-vehicle devices often require severe environmental properties such as vibration resistance, heat shock resistance, and high temperature and high humidity resistance. However, when the conventional capacitor as described above is used in a severe environment such as high temperature and high humidity, the larger the opening of the case (resin injection part), the higher the moisture absorption, and the stress such as vibration and temperature, There is a possibility that cracks may occur in the connection part of the capacitor element and the bus bar and the filling resin. In particular, when the components constituting the capacitor are repeatedly expanded and contracted due to temperature changes, the stress strain due to this acts toward the open surface (case opening), and cracks are likely to occur in the resin surface layer of the case opening. Even if the expansion rate and contraction rate of the parts are the same, the absolute amount of expansion and contraction is proportional to the magnitude. Therefore, the larger the capacitor, the more prominent the occurrence of cracks due to strain. Furthermore, if the case opening becomes large, the resin and the case are easily peeled off, and if peeled off, there is a risk of moisture absorption deterioration due to peeling.

  The present invention has been made to solve the above-described conventional drawbacks, and an object of the present invention is to provide a capacitor that is less prone to cracking of the filled resin and has improved durability against temperature changes.

  The capacitor of claim 1 is a capacitor in which the capacitor element 2 is housed in the case 1 and filled with resin, and a part of the capacitor is embedded in the resin layer 3 so as to partition the resin surface in the opening 7 of the case 1. It is characterized in that a partition member 15 whose other part protrudes from the resin surface is provided.

  The capacitor according to claim 2 is characterized in that the partition member 15 is configured by a flat plate body disposed such that the thickness direction T is substantially orthogonal to the depth direction D of the case 1.

  The capacitor according to claim 3 is characterized in that, in the partition member 15 of the flat plate-like body, the end portion 20 embedded in the resin layer 3 has a rounded shape.

  The capacitor according to a fourth aspect is characterized in that the partition member 15 is constituted by a rod member having a substantially circular cross section.

  According to the capacitor of the first aspect, since the surface layer of the resin layer can be partitioned on the opening side of the case by the partition member, the expansion and contraction of the component (the component constituting the capacitor) due to temperature change are repeated. It is possible to suppress the occurrence of cracks by dispersing stress strain due to the above. That is, the resin layer is hardly cracked and the durability against temperature change is improved. For this reason, the capacitor function can be stably exhibited over a long period of time even in a harsh environment such as in-vehicle use (in an environment such as high temperature and high humidity).

  According to the capacitor of the second aspect, since the partition member is constituted by a flat body disposed so that the thickness direction is substantially orthogonal to the depth direction of the case, the partition on the resin surface is surely provided. It is possible to stably distribute stress strain due to repeated expansion and contraction.

  According to the capacitor of claim 3, since the end portion embedded in the resin layer has a rounded shape in the partition member of the flat plate-like body, stress concentration can be prevented and effective in suppressing cracks. is there. For this reason, the high-temperature and high-humidity durability can be further improved, and the capacitor function can be exhibited with high accuracy even in a severe environment.

  According to the capacitor of claim 4, since the partition member is constituted by a bar member (round bar) having a substantially circular cross section, the portion embedded in the resin layer has a rounded shape, and prevents stress concentration. Can do. For this reason, the high-temperature and high-humidity durability can be further improved, and the capacitor function can be exhibited with high accuracy even in a severe environment.

  Next, specific embodiments of the capacitor of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a perspective view of the capacitor of the present invention, and FIG. 2 shows a cross-sectional view. The capacitor includes a case 1, a capacitor element 2 accommodated in the case 1, and a resin layer 3 formed by filling the case 1 with resin in a state where the capacitor element 2 is accommodated.

  The case 1 includes a bottom wall 5 and a peripheral wall 6 erected from the bottom wall 5, and an opening 7 is formed. The peripheral wall 6 includes a pair of long side walls 8 and 9 facing each other and a pair of short side walls 10 and 11 facing each other. A flat electrode 13 is connected to the end face 12 of the capacitor element 2.

  A partition member 15 is disposed in the opening 7 of the case 1. As shown in FIG. 4, the partition member 15 includes a pair of vertical bars 16 and 16 that connect the pair of long side walls 8 and 9 and a pair of horizontal bars that connect the pair of short side walls 10 and 11. This is a lattice body composed of 18 and 18. For this reason, the resin surface can be divided into nine. The partition member 15 is locked to a locking portion (not shown) provided at the upper edge of the peripheral wall 6 of the case 1. For example, the long side walls 8 and 9 and the short side walls 10 and 11 are provided with receiving pieces and cutouts as locking portions so that the bars 16 and 18 of the partition member 15 are received by the receiving pieces and cutouts. You can do it.

  Further, as shown in FIG. 2, each of the bars 16 and 18 is formed of a plate-like body whose thickness direction T is substantially orthogonal to the depth direction D of the case 1, and a part thereof is embedded in the resin layer 3. , The other part protrudes outward (exposed). And as shown in FIG. 3, the edge part (lower end part) 20 ... of each bar | burr 16 and 18 embed | buried under the resin layer 3 is made into the shape (R shape) which rounded.

  To assemble this capacitor, the resin for forming the resin layer 3 is filled in the state in which the capacitor element 2 of the case 1 is accommodated. At this time, as the resin to be filled, the upper end portions of the bars 16 and 18 are exposed from the resin layer 3 so as not to reach the opening end of the case 1. As shown in FIG. 2, a gap 21 is provided between the end 20 of each bar 16, 18 and the capacitor element 2. Note that the electrode 13 of the capacitor element 2 also protrudes outward from the opening 7 of the case 1 on one short side wall 11 side. Moreover, as resin of the resin layer 3, thermosetting resins, such as an epoxy resin and a urethane resin, can be used, for example, and the partition member 15 can also be comprised with the same resin. In this case, the material of the partition member 15 is preferably the same as that of the resin layer 3 in consideration of adhesion and the like, but other resins (for example, metals, etc.) may be used. ). Since the partition member 15 is partially embedded in the resin layer 3, it is not necessary to fix the partition member 15 to the case 1, and the partition member 15 is placed on the receiving piece or the like as described above. If only the resin is filled, the partition member 15 is fixed.

  In the above capacitor, even if the components constituting the capacitor repeat expansion and contraction due to temperature change, the partition member 15 partitions the resin surface in the opening 7 of the case 1, so that the expansion and contraction are repeated. It is possible to suppress the occurrence of cracks by dispersing stress strain due to the above. That is, the resin layer 3 is hardly cracked and the durability against temperature change is improved. For this reason, the capacitor function can be stably exhibited over a long period of time even in a harsh environment such as in-vehicle use (in an environment such as high temperature and high humidity). In addition, since the partition member 15 is configured by a flat body that is disposed so that the thickness direction is substantially perpendicular to the depth direction of the case 1, the resin surface can be reliably partitioned. Dispersion of stress strain due to repetition of expansion and contraction can be performed stably. In addition, since the end portions 20 of the bars 16 and 18 of the partition member 15 are rounded, stress concentration can be prevented, which is particularly effective in suppressing cracks. For this reason, the high-temperature and high-humidity durability can be further improved, and the capacitor function can be exhibited with high accuracy even in a harsh environment. Further, since the gap 21 is provided between the end 20 of each bar 16 and 18 and the capacitor element 2, the resin can enter the gap 21 and the capacitor element 2 can be surrounded by the resin. For this reason, it is excellent in moisture resistance and can exhibit a capacitor | condenser function with high precision. In particular, if the gap 21 is large, highly accurate moisture resistance can be exhibited.

  Next, FIG. 5 shows another embodiment, and the partition member 15 in this case is not constituted by a lattice body, and includes three vertical bars 16. For this reason, the resin surface layer is divided into four. The vertical bars 16 are also formed of a flat plate body, and the end portion 20 has a rounded shape. Even the partition member 15 engages with engaging portions (not shown) provided on the long side walls 8 and 9 of the peripheral wall 6. Since the other configuration of the capacitor shown in FIG. 5 is the same as that of the capacitor shown in FIG. 1 and the like, the same components as those in FIG.

  For this reason, the capacitor surface shown in FIG. 5 can also partition the resin surface layer, and like the capacitor shown in FIG. 1 and the like, stress strain due to repeated expansion and contraction is dispersed, and the resin layer 3 is hardly cracked. The durability against temperature changes is improved. For this reason, the capacitor function can be stably exhibited over a long period of time even in a harsh environment such as in-vehicle use (in an environment such as high temperature and high humidity).

  FIG. 6 shows another embodiment. In this capacitor, the partition member 15 is composed of three vertical bars 16..., But the vertical bar 16 in this case is a bar having a substantially circular cross section. It consists of members. Even the partition member 15 engages with engaging portions (not shown) provided on the long side walls 8 and 9 of the peripheral wall 6. Also. Each rod member has its substantially lower half embedded in the resin layer 3. Since the other configuration of the capacitor shown in FIG. 5 is the same as that of the capacitor shown in FIG. 1 and the like, the same components as those in FIG.

  For this reason, even the capacitor shown in FIG. 6 can partition the resin surface layer, and similarly to the capacitor shown in FIG. In this case, the capacitor function can be stably exhibited over a long period of time. In addition, since the partition member 15 is composed of a rod member having a substantially circular cross section, the portion embedded in the resin layer has a rounded shape, which can prevent stress concentration and is particularly effective in suppressing cracks. There are advantages to being effective.

  Although specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention. For example, as the capacitor element 2, various elements such as a wound element, a wound flat element, and a laminated element can be used. The number of capacitor elements 2 can be increased or decreased arbitrarily. The resin layer 3 is not limited to an epoxy resin or a urethane resin, and other thermosetting resins or thermoplastic resins can also be used. Furthermore, the number of the vertical bars 16 and the horizontal bars 18 constituting the partition member 15 can be increased or decreased. However, the number of the resin surface layers is determined by these numbers. The number of partitions will increase. If the number of compartments is small, the dispersion of stress strain due to repeated expansion and contraction will decrease, reducing the effect of suppressing the occurrence of cracks. Although the effect of suppressing the occurrence of this increases, the cost increases due to the increase in the number of parts. For this reason, it is necessary to determine the number and thickness dimensions of the vertical bars 16 and the embedding dimensions with respect to the resin layer 3 in consideration of the area of the opening 7 of the case 1 and the resin material of the resin layer 3. is there. Further, as shown in FIG. 1, a rod member having a substantially circular cross section may be used even when the partition member 15 is configured by a lattice. Further, the partition member 15 may be configured with only the horizontal bar 18, and the vertical bar 16 and the horizontal bar 18 are inclined with respect to the short side walls 10 and 11 and the long side walls 8 and 9. Even if it does, it may be connected as a bar between the corner parts (corner part of the opening part 7) which face relative surfaces (opposite each other). Each of these bars may be a flat plate or a bar member. In addition, when a bar member is used, the cross section may be an ellipse other than a circle, a triangle, a rectangle, a trapezoid, a pentagon, or another polygon, and is not limited to a solid body. It may be a hollow body. In addition, in the said embodiment, although the opening part 7 of the case 1 is made into the rectangular shape, even if the opening part 7 is square shape, another polygonal shape, a circle | round | yen, etc. may be sufficient. Moreover, when using this capacitor | condenser, it is not restricted to arrange | positioning so that the opening part 7 may face upwards, You may arrange | position so that the opening part 7 may face various directions, such as a downward direction and a side.

It is a perspective view which shows embodiment of the capacitor | condenser of this invention. It is sectional drawing of the said capacitor | condenser. It is a principal part expanded sectional view of the partition member of the said capacitor | condenser. It is a perspective view of the case of the said capacitor | condenser. It is a perspective view which shows other embodiment of the capacitor | condenser of this invention. It is sectional drawing which shows another embodiment of the capacitor | condenser of this invention.

Explanation of symbols

  1 .... Case, 2 .... Capacitor element, 3 .... Resin layer, 7 .... Opening, 15 .... Partition member, 20 .... End, D ... Depth direction, T ... Thickness direction

Claims (4)

  In the capacitor in which the capacitor element (2) is housed in the case (1) and filled with resin, a part of the capacitor element (2) is in the resin layer (3) so as to partition the resin surface in the opening (7) of the case (1). The capacitor | condenser characterized by providing the partition member (15) which is embed | buried in and the other part protrudes from the resin surface.   The partition member (15) is constituted by a flat plate body disposed so that the thickness direction (T) is substantially orthogonal to the depth direction (D) of the case (1). The capacitor of claim 1.   3. The capacitor according to claim 2, wherein, in the partition member (15) of the flat plate-like body, the end (20) embedded in the resin layer (3) has a rounded shape.   The capacitor according to claim 1, wherein the partition member (15) is a rod member having a substantially circular cross section.