JP7093990B2 - Capacitor - Google Patents

Description

The present invention relates to a capacitor in which a capacitor element and an electrode plate are housed in a case and filled with resin.

In a so-called resin molded capacitor in which a capacitor element and an electrode plate are housed in a case and filled with resin, one end of a metal heat dissipation member is positioned inside the resin and the other end is pulled out of the resin to cool the inside of the capacitor. When trying to do so, the insulation of the heat dissipation member may become a problem. That is, when the heat radiation member is placed near the electrode plate, the electrode plate is also pulled out of the resin for connection with an external device, so that it is a problem to secure the insulation between the heat radiation member and the electrode plate outside the resin. It becomes. In the capacitor, insulating paper is generally used as a method for ensuring insulation (see, for example, Patent Document 1). Further, a resin insulating plate may be used instead of the insulating paper (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2008-288242 Japanese Unexamined Patent Publication No. 2010-251400

However, since the insulating paper has high water absorption, moisture may enter the capacitor through the insulating paper, shortening the life of the capacitor. When an insulating plate is used, problems such as those of insulating paper are unlikely to occur, but the number of parts is increased, and since the assembly is performed while positioning, it takes time and effort to manufacture, which leads to an increase in cost.

Therefore, an object of the present invention is to provide a capacitor capable of inexpensively insulating the electrode plate and the heat radiating member.

The capacitor of the present invention is a capacitor in which a capacitor element 2, an electrode plate 3, 4 and a heat radiating member 5 are housed in a case 6 and filled with a resin 7, and the case 6 is an electrode drawn out of the resin 7. It is located between the plates 3 and 4 and the heat radiating member 5, and is characterized by including an insulating portion 62 that secures insulation between the electrode plates 3 and 4 and the heat radiating member 5.

Further, it is preferable that the heat radiating member 5 is provided with an insertion hole 5c, and the heat radiating member 5 is positioned by inserting the insulating portion 62 into the insertion hole 5c.

Since the case of the capacitor of the present invention is located between the electrode plate drawn out of the resin and the heat radiating member and has an insulating portion for ensuring insulation between the electrode plate and the heat radiating member, the capacitor is separately provided separately. There is no need to provide an insulator such as insulating paper or insulating plate. Further, since the case itself is provided with an insulating portion, the number of parts can be reduced as compared with the case where an insulator is separately provided, and since positioning is not required, assembly can be easily performed.

Further, if the heat radiating member is provided with an insertion hole and the heat radiating member is positioned by inserting the insulating portion into the insertion hole, the work efficiency of assembly is improved and at least the insulating portion and the heat radiating member are provided. It is possible to prevent misalignment with and, and it becomes easier to secure insulation.

It is an exploded perspective view which shows the capacitor which concerns on one Embodiment of this invention. It is a perspective view which shows the state which attached the heat dissipation member to a case. It is a perspective view which shows the state which accommodated a capacitor element, an electrode plate, and a heat dissipation member in a case. It is a cross-sectional view of a key point of a capacitor.

Next, an embodiment of the capacitor of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 to 4, the capacitor 1 of the present invention includes a plurality of capacitor elements 2, a pair of positive and negative electrode plates 3 and 4 for connecting the plurality of capacitor elements 2 in common, and a capacitor element 2 and an electrode plate. A heat radiating member 5 that discharges the heat of 3 and 4 to the outside, a case 6 that houses the capacitor element 2, each electrode plate 3, 4 and the heat radiating member 5, and a case 6 that is filled in the case 6 and the capacitor element 2 and each electrode. A resin 7 for sealing the plates 3 and 4 and the heat radiating member 5 is provided. Hereinafter, each component will be described, but the concept of "upper and lower" in the description is at the time of manufacturing, more specifically at the time of resin filling, and does not necessarily define the upper and lower at the time of use.

The capacitor element 2 is, for example, a film capacitor obtained by winding a metallized film on which metal is vapor-deposited on the surface of an insulating film, and as shown in FIG. 1, metal is sprayed on both end surfaces in the axial direction. The electrode portions 2a and 2b are formed. This capacitor element 2 has a flat shape when viewed from the axial direction, specifically a substantially track shape (a shape in which two parallel lines and both ends thereof are connected by a semicircle), and a flat portion 2c and a curved surface are formed on the outer periphery in the axial direction. It has a part 2d. A plurality of the capacitor elements 2 are arranged so that the flat portions 2c face each other while the electrode portions 2a and 2b are oriented vertically to form a capacitor element group.

The pair of positive and negative electrode plates 3 and 4 are made of a conductive plate material (metal plate) such as a copper plate or an aluminum plate, and are arranged so as to sandwich the capacitor element 2 from above and below. Hereinafter, the electrode plate 3 located above the capacitor element 2 is referred to as a first electrode plate, and the electrode plate 4 located below the capacitor element 2 is referred to as a second electrode plate. Regarding the positive and negative electrodes, for example, the first electrode plate 3 is used as the negative electrode and the second electrode plate 4 is used as the positive electrode, but they may be replaced.

The first electrode plate 3 has a substantially strip-shaped substrate portion 3a, an external connecting portion 3b extending upward from one side of the substrate portion 3a, and a side opposite to the side on which the external connecting portion 3b is extended. It is provided with an element connecting portion 3c extending in the horizontal direction from the side of the above. Specifically, the substrate portion 3a has a length that can face the upper electrode plates of all the capacitor elements 2 constituting the capacitor element group. The external connection portion 3b extends from substantially the center in the longitudinal direction of the substrate portion 3a, and a mounting hole 3d used for connection with an external device is provided in the vicinity of the tip end. The element connection portions 3c have a substantially tongue shape, and two are provided for each capacitor element 2.

In the second electrode plate 4, the substrate portion 4a has a substantially L-shaped vertical cross section, and the horizontal portion 4a1 facing the lower electrode portion 2b of each capacitor element 2 and the curved surface portion 2d of each capacitor element 2 face each other. It is substantially the same as the first electrode plate 3 except that it is composed of the vertical portion 4a2 and the external connection portion 4b is provided so as not to overlap with the external connection portion 3b of the first electrode plate 3. .. Therefore, the same subscript is added and detailed explanation is omitted.

The first electrode plate 3 and the second electrode plate 4 are manufactured by appropriately performing punching, bending, and cutting / bending on one metal plate. However, each part may be manufactured separately and integrated by welding or the like.

The case 6 includes a bottom portion 6a having a substantially rectangular shape in a plan view and side wall portions 6b erected from the four sides of the bottom portion 6a, respectively, and an opening 6c is provided on a surface (upper surface side) facing the bottom portion 6a. It is provided. Further, the side wall portion 6b adjacent to the external connection portions 3b and 4b of each of the electrode plates 3 and 4 is provided with an overhanging portion 61 projecting outward. The overhanging portion 61 is for arranging the heat radiating member 5, and is composed of a horizontal step portion 61a constituting the bottom of the overhanging portion 61 and a surrounding wall 61b surrounding the horizontal step portion 61a.

From the upper end of the enclosure wall 61b, a mounting leg 61c for mounting the capacitor 1 to an external device extends toward the outside of the case 6. The mounting legs 61c are also for supporting a portion of the heat radiating member 5 that is pulled out of the case 6 (a drawer portion 5b described later), and the heat radiating member 5 is arranged in the vicinity of the external connecting portions 3b and 4b. It is provided at a position closest to the external connection portions 3b and 4b (substantially in the center in the longitudinal direction of the case). Further, the mounting legs are similarly extended from the upper end of the other side wall portion 6b facing the overhanging portion 61. The mounting legs 6d are simply used for mounting on an external device. Since these mounting legs 61c and 6d are supposed to be bolted to an external device, bolt holes 61d and 6e are provided. However, instead of the bolt holes, bolts may be provided.

Further, the case 6 is located between the external connection portions 3b and 4b of the electrode plates 3 and 4 drawn out of the resin 7 and the heat radiation member 5 (drawer portion 5b), and the electrode plates 3 and 4 and the heat radiation member are provided. A plate-shaped insulating portion 62 for ensuring insulation between the 5 and the 5 is provided. Specifically, the insulating portion 62 extends upward from the horizontal step portion 61a of the overhanging portion 61 in parallel with the surrounding wall 61b and with a gap between the insulating wall 61b and the surrounding wall 61b. ing. Further, it is located substantially in the center in the longitudinal direction of the case. The upper end of the insulating portion 62 projects upward from the opening 6c so that even if the case 6 is filled with the resin 7, the upper end of the insulating portion 62 projects out of the resin 7. The protrusion length L1 from the resin 7 is at least longer than the protrusion length L2 of the heat radiating member 5 (see FIG. 4). Further, the width W1 of the insulating portion 62 is wider than the outer width W2 of the two external connecting portions 3b and 4b arranged in the longitudinal direction of the case and the width W3 of the drawer portion 5b of the heat radiating member 5 (see FIG. 3). Both ends of the insulating portion 62 are not in contact with the other side wall portions 6b, and the filling of the resin 7 into the overhanging portion 61 is not hindered.

The case 6 having the above configuration is manufactured by integrally molding a synthetic resin which is a non-conductive material including the insulating portion 62. However, the insulating portion 62 may be provided separately and integrated with an adhesive or the like. Further, it may be made of a conductive material except for the insulating portion 62. The resin 7 filled in the case 6 is, for example, an epoxy resin. However, the present invention is not limited to this, and various known resins such as urethane resin can be used.

The heat radiating member 5 is made of a plate material (metal plate) having high thermal conductivity such as a copper plate or an aluminum plate, and has conductivity. The heat radiating member 5 includes a main body portion 5a arranged along the side wall portion 6b provided with the overhanging portion 61, and a drawer portion 5b extending from the upper end of the main body portion 5a. Specifically, the main body portion 5a is composed of a vertical surface as a whole, but a horizontal portion 5a1 is provided substantially in the center in the vertical direction in order to follow the overhanging portion 61. Then, with the horizontal portion 5a1 as a boundary, it is divided into an upper vertical portion 5a2 and a lower vertical portion 5a3. As shown in FIG. 4, the upper vertical portion 5a2 is along the inner surface of the surrounding wall 61b, the horizontal portion 5a1 is along the upper surface of the horizontal step portion 61a, and the lower vertical portion 5a3 is from the horizontal step portion 61a. Also follows the inner surface of the lower side wall portion 6b.

Returning to FIG. 1, the horizontal portion 5a1 is provided with a slit-shaped opening substantially in the center in the longitudinal direction. This opening functions as an insertion hole 5c for inserting the insulating portion 62. The drawer portion 5b extends from substantially the center of the main body portion 5a in the longitudinal direction. The drawer portion 5b is composed of a heat transfer portion 5b1 located on the mounting leg 61c of the case 6 and a vertical portion 5b2 for pulling the heat transfer portion 5b1 out of the case 6. The heat transfer portion 5b1 is provided with a bolt hole 5d corresponding to the bolt hole 61d of the mounting leg 61c. The heat radiating member 5 is manufactured by appropriately punching, bending, and cutting a single metal plate in the same manner as the electrode plates 3 and 4, but each part is manufactured separately. However, they may be integrated by welding or the like.

Next, a method of manufacturing the capacitor 1 will be described. First, as described above, a plurality of capacitor elements 2 are arranged to form a capacitor element group, and the electrode plates 3 and 4 are connected to the capacitor element group to form a capacitor module. Specifically, the substrate portion 3a of the first electrode plate 3 is opposed to the upper electrode portion 2a of each capacitor element 2, and the element connection portion 3c and the electrode portion 2a are connected by soldering or the like. Further, the substrate portion 4a of the second electrode plate 4 is opposed to the lower electrode portion 2b of each capacitor element 2, and the element connection portion 4c and the electrode portion 2b are connected by soldering or the like.

Subsequently, the heat radiating member 5 is attached to the case 6. Specifically, the insulating portion 62 of the case 6 is inserted into the insertion hole 5c of the heat radiating member 5, and the horizontal portion 5a1 is positioned on the horizontal step portion 61a. When the heat radiating member 5 is inserted through the insulating portion 62, the heat transfer portion 5b1 is naturally located on the mounting legs 61c (see FIG. 2). Further, the position of the heat radiating member 5 is determined, and the positioning of the heat radiating member 5 is also performed at the same time.

Next, the capacitor module is housed in the case 6. At this time, the electrode portions 2a and 2b of the capacitor element 2 are accommodated so as to face up and down, and the external connection portions 3b and 4b of the electrode plates 3 and 4 are retracted from the case opening 6c to the outside of the case 6. .. When accommodated in this way, as shown in FIG. 3, the insulating portion 62 is located between the external connecting portions 3b and 4b of the electrode plates 3 and 4 and the drawing portion 5b of the heat radiating member 5. After that, the capacitor element 2, the electrode plates 3, 4 and the heat radiating member 5 are embedded in the resin 7 except for the external connection portions 3b and 4b and the drawing portion 5b, and the case 6 is filled with the resin 7 to fill the capacitor 1. Complete production.

In the capacitor 1 having the above configuration, the external connection portions 3b and 4b drawn out of the resin 7 and the lead-out portion 5b are close to each other at a distance where insulation cannot be secured unless an insulator is provided between them, but they are externally connected. Since the insulating portion 62 is provided so as to hide the drawer portion 5b behind when viewed from the portions 3b and 4b, it is possible to increase the creepage distance and secure the insulation between the two. Insulation is ensured by the resin 7 for the portion embedded in the resin 7. Further, since the insulating portion 62 is integrated with the case 6 and the heat radiating member 5 is inserted through the insulating portion 62, the positional relationship between the insulating portion 62 and the radiating member 5 does not shift, and the insulating portion 62 is insulated. Can be ensured. In particular, since the insulating portion 62 has a plate shape and the insertion hole 5c has a slit shape, rotation of the heat radiating member 5 can be prevented.

As shown in FIG. 4, the capacitor 1 is mounted on the housing 8 of an external device such as an inverter by using the mounting legs 61c and 6d. Since the heat transfer portion 5b1 of the heat radiating member 5 is located on the upper surface of the mounting leg 61c, the heat transfer portion 5b1 comes into contact with the housing 8 simply by attaching the capacitor 1 to the housing 8, and the capacitor 1 has a heat transfer portion 5b1. Heat can be transferred to the housing 8 side.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. For example, in the above embodiment, the overhanging portion 61 is provided, but it is not always necessary to provide the overhanging portion 61, and the insulating portion 62 may be extended directly from the bottom portion 6a and the side wall portion 6b of the case 6. Further, although the external connection portions 3b and 4b, the mounting legs 61c, and the drawer portion 5b are substantially at the center in the longitudinal direction of the case, if the three are at the same position, they may be appropriately moved, not limited to the substantially center. Further, both the external connection portion 3b of the first electrode plate 3 and the external connection portion 4b of the second electrode plate 4 were provided close to the drawer portion 5b of the heat dissipation member 5, but only one of them was close to each other. It may be provided. Further, in the above embodiment, the heat radiating member 5 and the second electrode plate 4 are brought into close contact with each other, but since the capacitor element 2 also generates heat, the capacitor element 2 and the heat radiating member 5 may be brought into close contact with each other.

The capacitor element 2 is not limited to a film capacitor, and various capacitor elements such as a ceramic capacitor may be used. As for the shape, various shapes such as a columnar shape and a prismatic shape can be adopted. The orientation of the capacitor element 2 is not particularly limited, and the electrodes 2a and 2b may be arranged so as to be laterally oriented.

1 Condenser 2 Condenser element 2a One electrode part 2b The other electrode part 2c Flat part 2d Curved surface part 3 First electrode plate 3a Board part 3b External connection part 3c Element connection part 3d Mounting hole 4 Second electrode plate 4a Board part 4a1 Horizontal Part 4a2 Vertical part 4b External connection part 4c Element connection part 4d Mounting hole 5 Heat dissipation member 5a Main body part 5a1 Horizontal part 5a2 Upper vertical part 5a3 Lower vertical part 5b Drawer part 5b1 Heat transfer part 5b2 Vertical part 5c Opening (insertion hole)
5d Bolt hole 6 Case 6a Bottom 6b Side wall 6c Opening 61 Overhang 61a Horizontal step 61b Surrounding wall 61c, 6d Mounting legs 61d, 6e Bolt hole 62 Insulation 7 Resin 8 External device housing L1 From resin of insulation Protruding length L2 Protruding length of heat dissipation member from resin W1 Width of insulating part W2 Outer width of two side-by-side external connection parts W3 Width of drawer part

Claims (2)

A capacitor in which a capacitor element, an electrode plate, and a heat dissipation member are housed in a case and filled with resin.
A capacitor in which the case is located between the electrode plate drawn out of the resin from the opening of the case and the heat radiating member, and has an insulating portion for ensuring insulation between the electrode plate and the heat radiating member. A capacitor in which a capacitor element, an electrode plate, and a heat dissipation member are housed in a case and filled with resin.
The case is located between the electrode plate drawn out of the resin and the heat radiating member, and is provided with an insulating portion for ensuring insulation between the electrode plate and the radiating member .
A capacitor in which an insertion hole is provided in the heat radiation member, and the heat radiation member is positioned by inserting an insulating portion through the insertion hole .

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