JP6926807B2 - Capacitor mounting structure - Google Patents

Description

The present invention relates to a capacitor mounting structure.

As a conventional capacitor mounting structure, for example, the technique described in Patent Document 1 is known. The capacitor mounting structure described in Patent Document 1 includes a substrate, a plurality of capacitors, a heat sink, a cover, a plurality of nuts, and a plurality of screws. The heat generated by the capacitor is dissipated to the heat sink and nut via screws and the like.

Japanese Unexamined Patent Publication No. 2016-197684

By the way, the present inventors are studying a configuration in which a heat radiating member is provided between a capacitor and a heat sink, and the heat of the capacitor is conducted to the heat sink by the heat radiating member. However, in such a configuration, if both end portions of the capacitor substrate are fixed to the heat sink by screws, the central portion of the capacitor substrate may bend due to the repulsive force of the heat radiating member. As a result, the contact between the capacitor and the heat radiating member becomes insufficient, and the heat radiating property of the capacitor may deteriorate.

An object of the present invention is to provide a capacitor mounting structure capable of suppressing bending of a capacitor substrate due to a repulsive force of a heat radiating member.

The capacitor mounting structure according to one aspect of the present invention is arranged on the mounting surface side of the capacitor board having a mounting surface, at least one capacitor mounted on the mounting surface of the capacitor board, and the heat of the capacitor. A heat dissipation member arranged between the capacitor and the heat sink and in contact with the capacitor and the heat sink, a plurality of fixing members for fixing the capacitor board to the heat sink on both ends of the capacitor board, and a side opposite to the mounting surface. It is provided with an insulating member arranged in the capacitor and having an electrically insulating property, and a pressing member arranged on the side opposite to the mounting surface and pressing the insulating member against the capacitor substrate.

In this capacitor mounting structure, an insulating member having electrical insulation and a holding member that presses the insulating member against the capacitor board are arranged on the side opposite to the mounting surface of the capacitor board on which the capacitor is mounted. As a result, even if the capacitor board is fixed to the heat sink by a plurality of fixing members on both ends of the capacitor board, the surface of the capacitor board opposite to the mounting surface on which the capacitor is mounted is pressed by the insulating member. It will be in a state of being suppressed by. Therefore, it is possible to prevent the capacitor substrate from bending due to the repulsive force of the heat radiating member.

A plurality of capacitors are mounted on the mounting surface from one end side of the capacitor board along the other end side of the capacitor board, and the insulating member extends from one end side of the capacitor board along the other end side of the capacitor board. At the same time, it may be fixed to the heat sink together with the capacitor substrate by a plurality of fixing members. According to this configuration, it is not necessary to add a new fixing member in order to fix the insulating member to the capacitor substrate. Therefore, it is not necessary to increase the area of the capacitor board in order to secure a place where the insulating member is fixed to the capacitor board. Further, it is not necessary to reduce the number of capacitors mounted on the capacitor board in order to secure a place where the insulating member is fixed to the capacitor board. Therefore, it is possible to prevent the capacitor substrate from bending due to the repulsive force of the heat radiating member while maintaining the size and capacitance of the capacitor substrate.

The holding member of the capacitor substrate may be a metal battery terminal fixed to the heat sink. According to this configuration, since the pressing member is made of metal, the rigidity of the pressing member is high. Therefore, it is possible to effectively suppress the bending of the capacitor substrate due to the repulsive force of the heat radiating member. Further, since the existing battery terminal is used as the holding member, it is not necessary to separately prepare the holding member, which is advantageous in terms of cost.

According to the present invention, there is provided a capacitor mounting structure capable of suppressing bending of a capacitor substrate due to a repulsive force of a heat radiating member.

It is a top view which shows the capacitor mounting structure which concerns on one Embodiment. It is sectional drawing along the line II-II of FIG. It is sectional drawing along the line III-III of FIG. It is sectional drawing which shows the capacitor mounting structure which concerns on a comparative example. It is a top view which shows the capacitor mounting structure which concerns on a comparative example. It is a top view which shows the capacitor mounting structure which concerns on a comparative example.

Hereinafter, various embodiments will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and duplicate description will be omitted.

The capacitor mounting structure 1 according to the present embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a plan view showing a capacitor mounting structure according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. FIG. 3 is a cross-sectional view taken along the line III-III of FIG.

The capacitor mounting structure 1 shown in FIGS. 1 to 3 is a structure for mounting a capacitor in, for example, an inverter that controls an AC motor or the like. As shown in FIGS. 1 to 3, the capacitor mounting structure 1 includes a capacitor substrate 10, a plurality of capacitors 20, a heat sink 30, a heat radiating member 40, a plurality of fixing members 50, an insulating member 60, and a battery. It is provided with a terminal (pressing member) 70.

The capacitor substrate 10 is, for example, a rectangular substrate. The capacitor board 10 has a mounting surface 10a on which the capacitor 20 is mounted and a non-mounting surface 10b on the opposite side of the mounting surface 10a.

The plurality of capacitors 20 are mounted on the mounting surface 10a of the capacitor board 10 along the other end side of the capacitor board 10 from one end side of the capacitor board 10 in the longitudinal direction (X-axis direction) of the capacitor board 10. Each capacitor 20 has a terminal 21, and the terminal 21 penetrates the capacitor substrate 10. In this embodiment, for example, a total of 15 capacitors 20 are mounted on the capacitor board 10. The plurality of capacitors 20 are arranged in two rows along the Y-axis direction on one end side in the Y-axis direction orthogonal to the X-axis direction.

The heat sink 30 is arranged on the mounting surface 10a side of the capacitor substrate 10. The heat sink 30 releases the heat of the capacitor 20. The heat sink 30 has a heat radiating portion 31 that covers a plurality of capacitors 20, and a fixing portion 32 that is integrated with the heat radiating portion 31 and to which the battery terminal 70 is fixed. The heat sink 30 is fixed to the capacitor substrate 10 by a plurality of fixing members 50. The heat sink 30 is made of a metal such as aluminum.

The heat radiating portion 31 of the heat sink 30 is formed in a dome shape that covers a plurality of capacitors 20. The heat radiating unit 31 extends from one end side to the other end side of the capacitor substrate 10 along the X-axis direction in the same direction as the direction in which the plurality of capacitors 20 are arranged. The fixing portion 32 of the heat sink 30 has a flat plate shape extending along the capacitor substrate 10. The heat sink 30 may have heat dissipation fins for improving heat dissipation.

The heat radiating member 40 is arranged between the plurality of capacitors 20 and the heat radiating portion 31 of the heat sink 30. The heat radiating member 40 is in contact with the plurality of capacitors 20 and the heat sink 30, and conducts the heat generated by the capacitors 20 to the heat sink 30. The heat conducted to the heat sink 30 is released to the outside. The heat radiating member 40 is made of, for example, a gel-like material having high thermal conductivity. The plurality of capacitors 20 are in a state of being pressed against the heat radiating member 40, and a part of the capacitors 20 is buried in the heat radiating member 40. The material constituting the heat radiating member 40 may have a high thermal conductivity and may not be in the form of a gel.

The plurality of fixing members 50 are provided on both ends of the capacitor substrate 10 in the X-axis direction, and fix the heat radiating portion 31 of the heat sink 30 and the capacitor substrate 10. As the fixing member 50, for example, a screw or a bolt may be used.

The insulating member 60 is arranged on the side opposite to the mounting surface 10a of the capacitor 20 (the non-mounting surface 10b side), and is interposed between the capacitor substrate 10 and the battery terminal 70. The insulating member 60 extends from one end side of the capacitor substrate 10 in the X-axis direction along the other end side of the capacitor substrate 10. The insulating member 60 extends along the X-axis direction and abuts on the battery terminal 70, and Z is orthogonal to the X-axis direction and the Y-axis direction from the main body 61 toward the non-mounting surface 10b of the capacitor substrate 10. It has protruding portions 62 and 63 that project in the axial direction. The protruding portion 62 is provided on one end side of the main body portion 61 in the Y-axis direction, and the protruding portion 62 is provided on the other end side of the main body portion 61 in the Y-axis direction. The protrusions 62 and 63 both extend along the X-axis direction. The ends of the protrusions 62 and 63 on the opposite side of the main body 61 are in contact with the non-mounting surface 10b of the capacitor substrate 10. With such a structure, the insulating member 60 covers the terminals 21 of the plurality of capacitors 20 on the non-mounting surface 10b side of the capacitor substrate 10. The insulating member 60 is made of, for example, a resin material having an electrically insulating property.

A plurality of through holes for fixing the insulating member 60 to the capacitor substrate 10 are provided on both ends of the main body 61 in the X-axis direction. Each through hole corresponds to the position where the fixing member 50 is arranged. The insulating member 60 is fixed to the heat sink 30 together with the capacitor substrate 10 by a plurality of fixing members 50.

The battery terminal 70 presses the insulating member 60 against the capacitor substrate 10. The battery terminal 70 is arranged on the side opposite to the mounting surface 10a (non-mounting surface 10b side) of the capacitor board 10. The battery terminal 70 includes a positive electrode battery terminal 70A and a negative electrode battery terminal 70B. The positive electrode battery terminal 70A and the negative electrode battery terminal 70B each extend along the Y-axis direction. Further, the positive electrode battery terminal 70A and the negative electrode battery terminal 70B are arranged apart from each other in the X-axis direction.

Each of the positive electrode battery terminal 70A and the negative electrode battery terminal 70B has a connecting portion 71 connected to an external cable or the like, and a fixing portion 72 integrated with the connecting portion 71 and fixed to the heat sink 30. The connecting portion 71 has a cylindrical shape and has an opening 71a. An external cable or the like is electrically connected to the battery terminal 70 (positive electrode battery terminal 70A or negative electrode battery terminal 70B) by being inserted into the opening 71a of the connection portion 71. The connecting portion 71 is in contact with the insulating member 60.

The fixed portion 72 is continuous with the connecting portion 71 on the side opposite to the opening 71a of the connecting portion 71. The fixed portion 72 has, for example, a flat plate shape. The fixing portion 72 is provided with a through hole for fixing the battery terminal 70 to the heat sink 30. A spacer 80 is arranged between the fixed portion 72 and the capacitor substrate 10. Further, a spacer 81 is arranged between the capacitor substrate 10 and the fixing portion 32 of the heat sink 30. Each of the positive electrode battery terminal 70A and the negative electrode battery terminal 70B is fixed by a fixing member 73 penetrating the fixing portion 72, the spacer 80, the capacitor substrate 10, the spacer 81, and the fixing portion 32 of the heat sink 30. In the present embodiment, the positive electrode battery terminal 70A and the negative electrode battery terminal 70B are each fixed by two fixing members 73. As the fixing member 73, for example, a screw or a bolt may be used. With such a structure, the insulating member 60 is pressed against the capacitor substrate 10 by the positive electrode battery terminal 70A and the negative electrode battery terminal 70B.

Next, the effect of the capacitor mounting structure 1 will be described with reference to FIGS. 4 to 6. FIG. 4 is a cross-sectional view showing a capacitor mounting structure according to a comparative example. 5 and 6 are plan views showing a capacitor mounting structure according to a comparative example.

As shown in FIG. 4, the capacitor mounting structure 100 according to the comparative example includes a capacitor substrate 110, a plurality of capacitors 120, a heat sink 130, a heat radiating member 140, and a fixing member 150. However, unlike the capacitor mounting structure 1 according to the present embodiment, the capacitor mounting structure 100 does not include an insulating member 60 and a battery terminal 70 that presses the insulating member 60 against the capacitor substrate 10. The capacitor board 110 is fixed to the heat sink 130 by fixing members 150 on both ends of the capacitor board 10. Therefore, the repulsive force of the heat radiating member 140 may cause the central portion of the capacitor substrate 110 to bend (see the two-dot chain line). As a result, the contact between the capacitor 120 and the heat radiating member 140 becomes insufficient, and the heat radiating property of the capacitor 120 deteriorates.

Further, when the insulating member 60 and the battery terminal 70 are not used as shown in FIGS. 5 and 6, in order to prevent the capacitor substrate 110 from bending, another fixing member 180 for fixing the capacitor substrate 110 to the heat sink 130 is used. Can be considered. In this case, as shown in FIG. 5, it is necessary to expand the area of the capacitor substrate 110 in order to secure a place where the capacitor substrate 110 is fixed to the heat sink 130 by the fixing member 180 (see the two-dot chain line). Therefore, it is difficult to maintain the size of the capacitor substrate 110. Further, when the capacitor board 110 is not enlarged as shown in FIG. 5, as shown in FIG. 6, the capacitor board 110 is secured in order to secure a place where the capacitor board 110 is fixed to the heat sink 130 by the fixing member 180. It is necessary to reduce the number of capacitors 120 mounted on the top. In this case, it is difficult to maintain the capacitance of the capacitor substrate 110.

On the other hand, in the capacitor mounting structure 1 according to the present embodiment, the insulating member 60 having electrical insulation and the insulating member 60 are placed on the opposite side of the mounting surface 10a of the capacitor board 10 on which the capacitor 20 is mounted. A battery terminal 70 that presses against the substrate 10 is arranged. As a result, even if the capacitor board 10 is fixed to the heat sink 30 by a plurality of fixing members 50 on both ends of the capacitor board 10, the non-mounting surface on the capacitor board 10 opposite to the mounting surface 10a on which the capacitor 20 is mounted is 10b is in a state of being pressed by the battery terminal 70 via the insulating member 60. Therefore, it is possible to prevent the capacitor substrate 10 from bending due to the repulsive force of the heat radiating member 40.

A plurality of capacitors 20 are mounted on the mounting surface 10a from one end side of the capacitor board 10 along the other end side of the capacitor board 10, and the insulating member 60 is mounted on the capacitor board 10 from one end side of the capacitor board 10. It extends along the other end side and is fixed to the heat sink 30 together with the capacitor substrate 10 by a plurality of fixing members 50. Therefore, it is not necessary to add a new fixing member in order to fix the insulating member 60 to the capacitor substrate 10. Therefore, it is not necessary to expand the area of the capacitor substrate 10 in order to secure a place where the insulating member 60 is fixed to the capacitor substrate 10. Further, it is not necessary to reduce the number of capacitors 20 mounted on the capacitor board 10 in order to secure a place where the insulating member 60 is fixed to the capacitor board 10. Therefore, it is possible to prevent the capacitor substrate 10 from bending due to the repulsive force of the heat radiating member 40 while maintaining the size and capacitance of the capacitor substrate 10.

Further, the insulating member 60 is pressed against the capacitor substrate 10 by a metal battery terminal 70 fixed to the heat sink 30. In this case, since the battery terminal 70 is made of metal, the rigidity of the battery terminal 70 is high. Therefore, it is possible to effectively suppress the bending of the capacitor substrate 10 due to the repulsive force of the heat radiating member 40. Further, since the existing battery terminal 70 is used as the holding member, it is not necessary to separately prepare the holding member, which is advantageous in terms of cost.

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. For example, the shape of the insulating member 60 is not particularly limited and can be appropriately changed such as an arch shape. Further, in the above embodiment, an example in which the insulating member 60 extends from one end side of the capacitor substrate 10 in the X-axis direction along the other end side of the capacitor substrate 10 has been described, but the insulating member 60 is the battery terminal 70. It may be a columnar member or the like arranged corresponding to the position of.

Further, in the above embodiment, an example in which a plurality of capacitors 20 are mounted on the capacitor board 10 has been described, but the number of capacitors 20 mounted on the capacitor board 10 may be one.

Further, in the above embodiment, an example in which the insulating member 60 is fixed to the heat sink 30 together with the capacitor substrate 10 by the plurality of fixing members 50 has been described, but the insulating member 60 is the capacitor substrate 10 by the plurality of fixing members 50. It does not have to be fixed to the heat sink together with.

Further, in the above embodiment, an example in which the pressing member for pressing the insulating member 60 against the capacitor substrate 10 is a plurality of battery terminals 70 (positive electrode battery terminal 70A and negative electrode battery terminal 70B) has been described, but the pressing member is a battery. It does not have to be the terminal 70. Further, the number of pressing members does not have to be plurality.

1 ... Capacitor mounting structure, 10 ... Capacitor substrate, 10a ... Mounting surface, 20 ... Capacitor, 30 ... Heat sink, 40 ... Heat dissipation member, 50 ... Fixing member, 60 ... Insulation member, 70 ... Battery terminal (holding member).

Claims (2)

A capacitor board with a mounting surface and
With at least one capacitor mounted on the mounting surface of the capacitor board,
A heat sink arranged on the mounting surface side of the capacitor substrate and releasing heat of the capacitor,
A heat radiating member arranged between the capacitor and the heat sink and in contact with the capacitor and the heat sink.
A plurality of fixing members for fixing the capacitor board to the heat sink on both ends of the capacitor board,
An insulating member arranged on the side opposite to the mounting surface and having electrical insulating properties,
It is provided with a pressing member which is arranged on the side opposite to the mounting surface and presses the insulating member against the capacitor substrate.
The pressing member, Oh Ru at a fixed metallic battery terminal to the heat sink, capacitor mounting structure. A plurality of the capacitors are mounted on the mounting surface from one end side of the capacitor board to the other end side of the capacitor board.
The insulating member extends from one end side of the capacitor substrate along the other end side of the capacitor substrate, and is fixed to the heat sink together with the capacitor substrate by the plurality of fixing members. Capacitor mounting structure described in .

Images