Bus bar assembly and method for manufacturing the same

Abstract

To provide a bus bar assembly which can improve adhesion between a bus bar and a frame body for a sealing resin body for protecting an electric element such as a semiconductor element, and a method for manufacturing the same.SOLUTION: A bus bar assembly includes a plurality of conductive bus bars which are arranged in the same plane in a state where a gap exists between opposite side faces, a frame body of an insulating resin which is fixed to the upper surfaces of the plurality of bus bars along the circumference in plan view of the bus bar group defined by the plurality of bus bars arranged in a state where the gap exists, and is annular in a plane view, and an insulating resin body which is electrodeposition-coated onto the outer surfaces of the plurality of bus bars, wherein the insulating resin body is provided with an upper surface exposure part and a lower surface exposure part for exposing the upper surface on one side in a thickness direction and the lower surface on the other side in the thickness direction in the plurality of bus bars.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a busbar assembly having a busbar and a frame body fixed to the busbar, and a manufacturing method thereof. [Background technology]

[0002] Planar busbar assemblies have been proposed and are used in a variety of fields, in which multiple busbars are arranged in parallel with gaps between them in the same plane, are electrically insulated from each other but mechanically connected.

[0003] The applicant of the present application has filed an application and been granted a patent for a planar busbar assembly comprising a plurality of busbars arranged in parallel with gaps between them in the same plane, an insulating resin film adhered to the upper surfaces of the plurality of busbars so as to span the gaps and connect the plurality of busbars while the gaps remain, and a rigid frame adhered to the upper surface of the insulating resin film so as to follow the peripheral region in a plan view of a busbar connection formed by connecting the plurality of busbars by the insulating resin film (see Patent Document 1 below).

[0004] The busbar assembly described in Patent Document 1 is effective in that it allows greater freedom in designing the opening width of the gap and can improve manufacturing efficiency compared to planar busbar assemblies in which the gap is filled with insulating resin. However, there is room for improvement in the adhesion between the components, i.e., the adhesion between the busbar and the insulating resin film, and the adhesion between the insulating resin film and the frame.

[0005] Furthermore, in the busbar assembly described in Patent Document 1, a plurality of busbars are arranged in parallel, which makes it difficult to reduce the size of the assembly in the planar direction.

[0006] In this regard, the applicant has also filed an application for a busbar assembly comprising: a conductive busbar; an insulating resin film adhered to the upper surface of the busbar, the insulating resin film having an opening exposing at least a portion of the upper surface of the busbar to form an element mounting portion; and a conductive and rigid frame body having a central opening that penetrates in the vertical direction and is adhered to the upper surface of the insulating resin film so as to follow the peripheral region of the busbar in a planar view, the lower surface of the busbar being exposed to the outside to form a busbar side external connection portion that can be connected to the outside, and the frame body being provided with an element connection portion that can be electrically connected via an electrical connection member such as a wire to an electrical element mounted on the element mounting portion, and a frame body side external connection portion that can be electrically connected to the outside (see Patent Document 2 below).

[0007] The busbar assembly described in Patent Document 2 is useful in that it can reduce the number of busbars by using the frame body as either the anode or the cathode, and therefore can achieve smaller size in the planar direction and lower costs compared to the busbar assembly described in Patent Document 1.

[0008] However, even in the busbar assembly described in Patent Document 2, there is room for improvement in the adhesion between the components, i.e., the adhesion between the busbar and the insulating resin film, and the adhesion between the insulating resin film and the frame. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Patent No. 6788767 [Patent Document 2] JP 2022-061249 A Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made in consideration of the conventional technology, and has an object to provide a busbar assembly that can improve adhesion between a busbar and a frame body for an encapsulating resin body that protects electrical elements, such as semiconductor elements, mounted on the busbar, and a method for manufacturing the same. [Means for solving the problem]

[0011] In order to achieve the above-mentioned object, the present invention provides a busbar assembly comprising: a plurality of conductive busbars arranged in the same plane with a gap between opposing side surfaces; an insulating resin frame body that is annular in a planar view and fixed to the upper surfaces of the plurality of busbars so as to follow the planar periphery of a busbar group defined by the plurality of busbars arranged with the gap; and an insulating resin body that is electrocoated onto the outer surfaces of the plurality of busbars, wherein the insulating resin body has an upper surface exposed portion and a lower surface exposed portion that respectively expose the upper surfaces of the plurality of busbars on one thickness direction side and the lower surfaces of the plurality of busbars on the other thickness direction side.

[0012] Preferably, a boundary between each of the plurality of bus bars and the frame body is covered with the insulating resin body.

[0013] In one embodiment, the frame body can have an inner frame portion located on the inside in a plan view, and an outer frame portion surrounding the inner frame portion with a gap therebetween in a plan view.

[0014] For example, at least one of the opposing side surfaces of the inner frame portion and the outer frame portion is inclined so that the width of the gap narrows from one side to the other side in the thickness direction. Instead, at least one of the opposing side surfaces of the inner frame portion and the outer frame portion is inclined so that the width of the gap increases from one side to the other side in the thickness direction.

[0015] The frame body may be disposed such that an inner circumferential surface overlaps with the bus bar group in a plan view and at least a portion of an outer circumferential surface is positioned outward from the bus bar group in a plan view.

[0016] Among the side surfaces of the busbar, a side surface that forms an outer peripheral surface of the busbar assembly may be an inclined surface that approaches the center of the busbar assembly in a plan view as it moves from one side to the other side in a thickness direction.

[0017] The frame may be disposed such that an outer peripheral surface thereof is positioned inside an outer edge of the busbar main body.

[0018] At least one of the opposing side surfaces of the plurality of bus bars may be an inclined surface.

[0019] The present invention also provides a method for manufacturing a busbar assembly including a plurality of conductive busbars arranged in the same plane with gaps between opposing side surfaces, and an insulating frame body having an annular shape in plan view fixed to upper surfaces of the plurality of busbars, the method including the steps of: preparing a conductive metal plate for busbars, the conductive metal plate having a busbar assembly forming region having the same thickness as the busbars and the same external shape in plan view as a busbar group defined by the plurality of busbars arranged with the gaps; forming one or more slits in the busbar assembly forming region that penetrate between the upper and lower surfaces and have the same width as the gaps, thereby forming a plurality of busbar forming sites corresponding to the plurality of busbars; and insert molding an insulating resin. the insulating resin body coating step of providing an insulating resin body on the outer surface of the busbar assembly formation area by electrochemical coating; a busbar exposure step of exposing at least a portion of the portion of the upper surface of each of the plurality of busbar formation sites that is surrounded by the frame body and at least a portion of the lower surface of each of the plurality of busbar formation sites; and a cutting step that is performed after the busbar exposure step or after the insulating resin body coating step and before the busbar exposure step, in which the busbar assembly formation area is cut from the conductive metal flat plate for busbars.

[0020] The present invention also provides a busbar assembly comprising: a conductive busbar; an insulating resin frame body that is annular in a planar view and fixed to an upper surface of the busbar so as to follow the planar periphery of the busbar; conductive connection terminals that are provided on the frame body so as to be accessible from the outside; and an insulating resin body that is electrochemically coated on the outer surface of the busbar, wherein the insulating resin body has an upper surface exposed portion and a lower surface exposed portion that expose the upper surface and lower surface of the busbar, respectively.

[0021] The present invention also provides a method for manufacturing a busbar assembly including a conductive busbar and an insulating frame body provided on an upper surface of the busbar to fit along a peripheral region of the busbar in a planar view, the method including the steps of: preparing a conductive metal flat plate for a busbar having a busbar forming region for forming the busbar; a frame body forming step of forming the frame body along the peripheral region of the busbar forming region in a planar view by insert molding with an insulating resin; an insulating resin body covering step of providing an insulating resin body on the outer surface of the busbar forming region by electrodeposition coating; a connection terminal installation step of providing a conductive connection terminal on the outer surface of the frame body; a busbar exposing step of exposing at least a part of the upper surface of the busbar forming region and at least a part of the lower surface of the busbar forming region after the insulating resin body covering step and before the connection terminal installation step or after the connection terminal installation step; and a cutting step of cutting the busbar forming region from the conductive metal flat plate for a busbar. Effect of the Invention

[0022] The bus bar assembly according to the present invention can improve adhesion between the bus bar and a frame for a sealing resin body that protects an electrical element, such as a semiconductor element, mounted on the bus bar. Furthermore, according to the method for manufacturing a busbar assembly according to the present invention, the busbar assembly can be manufactured efficiently. [Brief description of the drawings]

[0023] [Figure 1]1(a) and (b) are a plan view and a cross-sectional view taken along line I(b)-I(b) in FIG. 1(a), respectively, of a busbar assembly according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a vertical cross-sectional view of a semiconductor module in which semiconductor elements such as LEDs are mounted on the bus bar assembly according to the first embodiment. [Diagram 3] FIG. 3 is a plan view of a conductive metal plate for a busbar used in one manufacturing method of the assembly according to embodiment 1 (hereinafter sometimes referred to as the first manufacturing method), and shows the state after completion of the slit forming process in the first manufacturing method. [Figure 4] 4(a) is an enlarged view of part IV(a) in FIG. 3, and FIG. 4(b) is a cross-sectional view taken along line IV(b)-IV(b) in FIG. 4(a). [Diagram 5] FIG. 5 is a plan view of the conductive metal flat plate for bus bars after the frame body forming step in the first manufacturing method. [Figure 6] FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. [Figure 7] FIG. 7 is a plan view of the conductive metal flat plate for bus bars after the insulating resin body covering step in the first manufacturing method. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. [Figure 9] 9(a) and 9(b) are schematic vertical cross-sectional views of a bottom surface exposing process and a top surface exposing process, respectively, in the bus bar exposing step in the first manufacturing method. [Figure 10] FIG. 10 is a plan view of the conductive metal flat plate for bus bars for illustrating the cutting step in the first manufacturing method. [Figure 11] 11(a) and (b) are a plan view and a cross-sectional view taken along line XI(b)-XI(b) in FIG. 11(a), respectively, of a busbar assembly according to a first modified example of the first embodiment. [Figure 12]Figures 12(a) and 12(b) are respectively a plan view and a cross-sectional view taken along line XII(b)-XII(b) in Figure 12(a) of a busbar assembly according to a second modified example of the first embodiment, and Figure 12(c) is a cross-sectional view of a modified structure of the second modified example. [Figure 13] 13(a) and (b) are a plan view and a cross-sectional view taken along line XIII(b)-XIII(b) in FIG. 13(a), respectively, of a busbar assembly according to a third modified example of the first embodiment. [Figure 14] Figures 14(a) and 14(b) are respectively a plan view and a cross-sectional view taken along line XIV(b)-XIV(b) in Figure 14(a) of a busbar assembly according to a fourth modified example of the first embodiment, and Figure 14(c) is a cross-sectional view of a modified structure of the fourth modified example. [Figure 15] 15(a) and (b) are a plan view and a cross-sectional view taken along line XV(b)-XV(b) in FIG. 15(a) of a busbar assembly according to a second embodiment of the present invention. [Figure 16] FIG. 16 is a vertical cross-sectional view of a semiconductor module in which semiconductor elements such as LEDs are mounted on the bus bar assembly according to the second embodiment. [Figure 17] FIG. 17 is a plan view of a conductive metal flat plate for bus bars used in one manufacturing method (hereinafter, sometimes referred to as a second manufacturing method) of the assembly according to the second embodiment. [Figure 18] FIG. 18 is a plan view of the conductive metal flat plate for bus bars after the frame body forming step in the second manufacturing method. [Figure 19] FIG. 19 is a cross-sectional view taken along line XIX-XIX in FIG. [Figure 20] FIG. 20 is a plan view of the conductive metal flat plate for bus bars after the insulating resin body covering step in the second manufacturing method. [Figure 21] FIG. 21 is a cross-sectional view taken along line XXI-XXI in FIG. [Figure 22]22(a) and 22(b) are schematic vertical cross-sectional views of a lower surface exposing process and an upper surface exposing process, respectively, in the bus bar exposing step in the second manufacturing method. [Diagram 23] FIG. 23 is a plan view of the conductive metal flat plate for bus bars, illustrating the cutting step in the second manufacturing method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] First embodiment Hereinafter, an embodiment of a busbar assembly according to the present invention will be described with reference to the accompanying drawings. 1(a) and (b) show a plan view of a busbar assembly 1A according to the present embodiment and a cross-sectional view taken along line I(b)-I(b) in FIG. 1(a), respectively.

[0025] As shown in Figures 1(a) and 1(b), the busbar assembly 1A comprises a plurality of conductive busbars 10 arranged in the same plane with gaps 19 between opposing side surfaces, an insulating frame body 30 fixed to the upper surfaces of the plurality of busbars 10, and an insulating resin body 40 provided on the outer surfaces of the plurality of busbars 10 by electrochemical coating.

[0026] The bus bar 10 is made of a conductive metal such as Cu. The busbar assembly 1A in this embodiment has three busbars, namely, first to third busbars 10(1) to 10(3), as the plurality of busbars 10, and has first and second gaps 19(1), 19(2) as the gaps 19.

[0027] That is, the busbar assembly 1A has the first busbar 10(1), a second busbar 10(2) arranged adjacent to the first busbar 10(1) via a first gap 19(1), and a third busbar 10(3) arranged adjacent to the second busbar 10(2) via a second gap 19(2).

[0028] In the vertical cross-sectional view shown in FIG. 1(b), each of the bus bars 10(1) to 10(3) has an upper surface on one side in the thickness direction to which the frame body 30 is adhered, a lower surface on the other side in the thickness direction opposite the upper surface, and a side surface facing the adjacent bus bars 10(1) to 10(3) with the gap 19 therebetween.

[0029] The frame body 30 is formed from an insulating resin and is fixed to the upper surfaces of the multiple busbars 10 so as to follow the planar peripheral edge of the busbar group 20 defined by the multiple busbars 10 (in this embodiment, the first to third busbars 10(1) to 10(3)) that are arranged on the same plane with the gaps 19 remaining therebetween.

[0030] Specifically, as shown in Figures 1(a) and (b), the frame body 30 is annular in a plan view, having a central opening 35 that opens at least a portion of the upper surfaces of the plurality of busbars 10 (in this embodiment, the first to third busbars 10(1) to 10(3)) upward. The frame 30 is formed from an insulating resin such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), or polyphenylene sulfide (PPS).

[0031] The insulating resin body 40 and the frame body 30 are provided by electrochemically coating an insulating resin material (preferably Insulead (registered trademark)) having heat resistance and insulating properties, such as polyamideimide, polyimide, polyamide, epoxy, etc., on the exposed surfaces of the plurality of bus bars 10 (in this embodiment, the first to third bus bars 10(1) to 10(3)). Therefore, the boundaries between each of the plurality of bus bars 10 and the frame body 30 are also covered with the insulating resin body 40.

[0032] The insulating resin body 40 is provided with upper surface exposed portions and lower surface exposed portions that expose the upper surfaces and lower surfaces of the plurality of bus bars 10, respectively.

[0033] In this embodiment, the insulating resin body 40 has one or more openings as the upper surface exposure portion within the central opening 35 of the frame body 30, which expose the upper surfaces of the multiple busbars 10.

[0034] Specifically, as shown in Figures 1(a) and (b), in this embodiment, the insulating resin body 40 is provided with, as the upper surface exposure portions, a first resin body opening 40(1) that exposes a predetermined region of the upper surface of the first bus bar 10(1), a second resin body opening 40(2) that exposes a predetermined region of the upper surface of the second bus bar 10(2), and a third resin body opening 40(3) that exposes a predetermined region of the upper surface of the third bus bar 10(3).

[0035] As shown in FIG. 1(b), in this embodiment, the lower surface exposing portion is configured to expose the entire lower surfaces of the plurality of bus bars 10.

[0036] FIG. 2 shows a vertical cross-sectional view of an example of a semiconductor module 101 in which a semiconductor element 110 such as an LED is mounted on the bus bar assembly 1A. The semiconductor module 101 includes, as the semiconductor element 110, a first and a second semiconductor element 110(1) and 110(2).

[0037] Each of the first and second semiconductor elements 110(1), 110(2) has an upper electrode layer and a lower electrode layer 111, 112, respectively, on an upper surface on one side in the thickness direction and on a lower surface on the other side in the thickness direction, and has an element body 115 between the upper electrode layer and the lower electrode layer 111, 112.

[0038] In the semiconductor module 101, the first and second bus bars 10(1), 10(2) act as a first electrode which is one of the positive and negative electrodes (e.g., the positive electrode), and the third bus bar 10(3) acts as a second electrode which is the other of the positive and negative electrodes (e.g., the negative electrode).

[0039] That is, the first semiconductor element 110(1) has the lower electrode layer 112 fixed in an electrically connected state to the area of ​​the upper surface of the first bus bar 10(1) that acts as a first electrode, which is exposed by the first resin body opening 40(1), and the upper electrode layer 111 electrically connected to the area of ​​the upper surface of the third bus bar 10(3) that acts as a second electrode, which is exposed by the third resin body opening 40(3), via a first electrical connection member 120(1) such as wire bonding.

[0040] The second semiconductor element 110(2) has the lower electrode layer 112 fixed in an electrically connected state to a region of the upper surface of the second bus bar 10(2) that acts as a first electrode, the region being exposed by the second resin body opening 40(2), and the upper electrode layer 111 electrically connected via a second electrical connection member 120(2) such as wire bonding to a region of the upper surface of the third bus bar 10(3) that acts as a second electrode, the region being exposed by the third resin body opening 40(3).

[0041] Preferably, a plating layer (not shown) is provided on the upper surfaces of the first to third bus bars 10(1) to 10(3). In this case, the lower electrode layers 112 of the first and second semiconductor elements 110(1), 110(2) are die-bonded so as to be electrically connected to the plating layers on the upper surfaces of the first and second bus bars 10(1), 10(2), respectively, and the upper electrode layers 111 of the first and second semiconductor elements 110(1), 110(2) are wire-bonded to a plating layer (not shown) provided on the upper surface of the third bus bar 10(3) by the first and second electrical connection members 120(1), 120(2), respectively.

[0042] In the bus bar assembly 1A, the lower surfaces of the plurality of bus bars 10 (in this embodiment, the first to third bus bars 10(1) to 10(3)) act as connection terminals to the outside.

[0043] In addition, the reference numeral 130 in FIG. 2 denotes a sealing resin layer that is adhered to the upper surface of the bus bar assembly 1A to protect components such as the first and second semiconductor elements 110(1), 110(2) and the first and second electrical connection members 120(1), 120(2) mounted on the bus bar assembly 1A.

[0044] The frame 30 prevents the resin material forming the sealing resin layer 130 from flowing out before hardening when the sealing resin layer 130 is provided. The sealing resin layer 130 is formed of a transparent resin material such as polyimide, polyamide, or epoxy.

[0045] According to the bus bar assembly 1A having such a configuration, the first to third bus bars 10(1) to 10(3) are arranged in the same plane, so that the size can be reduced as much as possible in the vertical direction (thickness direction).

[0046] Furthermore, according to the busbar assembly 1A, adjacent busbars 10 are arranged so as to face each other on their side surfaces. Therefore, the facing area between adjacent busbars can be made as small as possible, compared to a stacked busbar assembly in which multiple busbars are stacked one above the other. This makes it possible to effectively prevent or reduce leakage current from flowing between adjacent busbars 10.

[0047] Furthermore, the busbar assembly 1A has the advantage of being able to increase the degree of freedom in the opening width of the gaps 19 and improve manufacturing efficiency, compared to a configuration (hereinafter referred to as the comparative configuration) in which the relative positions of multiple busbars 10 arranged in the same plane with gaps 19 between them are maintained by an insulating resin filled in the gaps 19.

[0048] In other words, in the comparative configuration, if the opening width of gap 19 is narrowed too much in order to reduce the size of the entire busbar assembly in the planar direction, the surface tension of the insulating resin material makes it difficult, and in some cases may make it impossible, to fill gap 19 with the insulating resin material.

[0049] In contrast, in the busbar assembly 1A of this embodiment, the relative positions of the first to third busbars 10(1) to 10(3), which are arranged in the same plane with the gaps 19 therebetween, are maintained by the frame body 30 fixed to the upper surfaces of the first to third busbars 10(1) to 10(3) and the insulating resin body 40 provided by electrochemical coating on the outer surfaces of the first to third busbars.

[0050] Therefore, in bus bar assembly 1A according to the present embodiment, the degree of freedom in the opening width of gap 19 can be increased, and the holding strength of multiple bus bars 10 can be increased.

[0051] Furthermore, in the bus bar assembly 1A according to the present embodiment, the boundaries between the plurality of bus bars 10 and the frame body 30 are covered with the insulating resin body 40.

[0052] Therefore, the adhesion between the bus bars 10 and the frame body 30 can be improved and maintained at a good level.

[0053] In bus bar assembly 1A according to the present embodiment, the entire lower surfaces of the first to third bus bars 10(1) to 10(3) are exposed. Therefore, when the bus bar assembly 1A is used as a semiconductor module 101, the heat dissipation characteristics via the lower surfaces of the first to third bus bars 10(1) to 10(3) can be improved.

[0054] Hereinafter, an example (first manufacturing method) of the manufacturing method of the bus bar assembly 1A will be described. FIG. 3 shows a plan view of a conductive metal plate 200 for bus bars used in the first manufacturing method. FIG. 4(a) shows an enlarged view of part IV(a) in FIG. 4, and FIG. 4(b) shows a cross-sectional view taken along line IV(b)-IV(b) in FIG. 4(a).

[0055] As shown in Figures 3 and 4, the first manufacturing method includes a step of preparing a conductive metal flat plate 200 for busbars, the conductive metal flat plate 200 having a busbar assembly forming region 210 having the same external shape in a planar view as a busbar group 20 defined by the plurality of busbars 10 (in this embodiment, the first to third busbars 10(1) to 10(3)) that have the same thickness as the first to third busbars 10(1) to 10(3) and are arranged with the gaps 19 present, and a slit forming step of forming a slit 215 in the busbar assembly forming region 210 that has the same width as the gaps 19 and penetrates between a first surface 211 on one side in the thickness direction and a second surface 212 on the other side in the thickness direction. 3 and 4 show the state after the slit forming step is completed.

[0056] As described above, the busbar assembly 1A according to the present embodiment has three busbars, that is, the first to third busbars 10(1) to 10(3), as the plurality of busbars 10. Therefore, in the busbar assembly forming region 210, first and second slits 215(1), 215(2) are formed as the slits 215. For example, when manufacturing a bus bar assembly in which two bus bars are arranged in parallel, one slit is formed.

[0057] As shown in Figures 3 and 4(a), in this embodiment, the conductive metal plate 200 for a busbar has a busbar row 205 including a plurality of the busbar assembly forming regions 210 arranged in series along the Y direction in the XY plane in which the conductive metal plate 200 is located, and a connecting region 230 connecting adjacent busbar assembly forming regions 210 in the Y direction, so that processing can be performed simultaneously on the plurality of busbar assembly forming regions 210.

[0058] In this embodiment, the conductive metal plate 200 for busbars has a pair of gripping pieces 207 respectively connected to one side and the other side of the longitudinal direction (Y direction) of the busbar row 205, and alignment holes 208 are provided in the pair of gripping pieces 207.

[0059] It is also possible to arrange a plurality of busbar rows 205 in parallel in the X direction, and to integrally hold the plurality of busbar rows 205 arranged in parallel in the X direction by the pair of gripping pieces 207, 207. According to this modified configuration, a larger number of bus bar assemblies 1A can be manufactured at the same time.

[0060] In this embodiment, the busbar assembly forming region 210 has its Y-direction length set to be the same as the length of the busbar assembly 1A in a direction parallel to the gap 19, and its X-direction length set to be the same as the length of the busbar forming portion 210 in a direction perpendicular to the gap 19 of the busbar assembly 1A.

[0061] The slits 215(1), 215(2) form the first and second gaps 19(1), 19(2), and have the same width as the corresponding first and second gaps 19(1), 19(2). The widths of the first and second gaps 19(1), 19(2) are determined according to the specifications of the busbar assembly 1A.

[0062] As shown in FIG. 4(a), in this embodiment, first and second slits 215(1), 215(2) formed in one busbar assembly forming area 210A extend at one longitudinal side (Y direction) into one connecting area 230A(1) connected to one longitudinal side (Y direction) of the one busbar assembly forming area 210A, and extend at the other longitudinal side (Y direction) into another connecting area 230A(2) connected to the other longitudinal side (Y direction) of the one busbar assembly forming area 230A.

[0063] Then, in a state after the slit forming process, first to third busbar forming regions 220(1) to 220(3) adjacent to each other via the first and second slits 215(1), 215(2) formed in the one busbar assembly forming region 210A are configured to be maintained in a connected state to each other via the one connecting region 230A(1) and the other connecting region 230A(2). With this configuration, the first and second slits 215(1), 215(2) (the first and second gaps 19(1), 19(2)) can be formed with high precision.

[0064] The first manufacturing method includes a frame forming step of forming the frame 30 along the periphery of the bus bar assembly forming region 210 in a plan view by insert molding an insulating resin.

[0065] FIG. 5 shows a plan view of the conductive metal plate 200 for bus bars after the frame body forming step. FIG. 6 shows a cross-sectional view taken along line VI-VI in FIG.

[0066] The frame body forming process is configured to place the busbar assembly forming area 210 in a mold (not shown) that defines a frame body forming space, inject an insulating resin such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) or the like into the frame body forming space, and then harden the insulating resin by heat treatment or the like to form the frame body 30 fixed to the upper surface of the busbar assembly forming area 210.

[0067] The first manufacturing method includes, after the frame body forming step, an insulating resin body coating step of providing an insulating resin body 40 on the outer surface of the bus bar assembly forming region 210 by electrodeposition coating.

[0068] FIG. 7 shows a plan view of the conductive metal plate 200 for bus bars in a state after the insulating resin covering step. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG.

[0069] The insulating resin body 40 is provided by electrocoating an insulating resin material (preferably Insulead (registered trademark)) having heat resistance and insulating properties, such as polyamideimide, polyimide, polyamide, epoxy, etc., in the busbar forming region 210 where the insulating frame body 30 is provided, by which the insulating resin body 40 is provided over the entire outer surface of the plurality of busbar forming portions 220 (in this embodiment, the first to third busbar forming portions 220(1) to 220(3)) that is exposed after the frame body is formed.

[0070] In other words, the insulating resin body 40 produced by the insulating resin body covering process covers the boundaries between the multiple busbar forming portions 220 (in this embodiment, the first to third busbar forming portions 220(1) to 220(3)) and the frame body 30, thereby effectively preventing or reducing the occurrence of gaps between the multiple busbars 10 (in this embodiment, the first to third busbars 10(1) to 10(3)) and the frame body 30.

[0071] The first manufacturing method further includes a busbar exposure process including an upper surface exposure process that exposes at least a portion of the upper surface of each of the plurality of busbar forming regions 220 that is surrounded by the frame body 30, and a lower surface exposure process that exposes at least a portion of the lower surface of each of the plurality of busbar forming regions 220.

[0072] In the present embodiment, the bus bar exposing step is configured to irradiate the portion to be exposed with laser light.

[0073] 9(a) and (b) are schematic vertical cross-sectional views of the lower surface exposing process and the upper surface exposing process, respectively. In addition, the symbol L in FIGS. 9(a) and (b) denotes a laser beam.

[0074] As described above, the lower surface exposed portion of the bus bar assembly 1A is configured to expose the entire lower surfaces of the first to third bus bars 10(1) to 10(3). Therefore, in the present embodiment, as shown in FIG. 9(a), the lower surface exposing process is configured to expose the entire lower surfaces of the first to third busbar forming portions 220(1) to 220(3).

[0075] Moreover, the upper surface exposed portion of the bus bar assembly 1A has the first to third resin body openings 40(1) to 40(3). Therefore, in the present embodiment, as shown in FIG. 9(b), the upper surface exposing process is configured to form the first to third resin body openings 40(1) to 40(3) in the insulating resin body 40.

[0076] The first manufacturing method further includes a cutting step of cutting the bus bar assembly forming region 210 from the conductive metal plate 200 for bus bars.

[0077] The cutting step is configured to cut the bus bar assembly forming area 210 along cutting lines C1 and C2 that respectively extend along edges on one side and the other side in the Y direction, as shown in FIG.

[0078] In the present embodiment, the cutting step is performed after the bus bar exposing step, but instead, it is also possible to perform the cutting step after the insulating resin covering step and before the bus bar exposing step. In this case, the bus bar exposing step is performed after the cutting step.

[0079] 11(a) and (b) show a plan view and a cross-sectional view taken along line XI(b)-XI(b) in FIG. 11(a), respectively, of a busbar assembly 1B according to a first modified example of the present embodiment.

[0080] In this embodiment, as shown in FIG. 1(b), the outer peripheral surface of the frame body 30 and the outer peripheral surface of the busbar group 20 (the side surfaces of the plurality of busbars 10(1) to 10(3) that form the outer peripheral surface of the busbar assembly 1A) are aligned in the planar direction of the busbar assembly 1A.

[0081] In contrast, in the first modified example 1B, as shown in FIG. 11(b), the frame body 30 is positioned so that its inner circumferential surface overlaps with the busbar group 20 in a planar view and at least a portion of its outer circumferential surface is positioned outward from the busbar group 20 in a planar view.

[0082] In the first modified example 1B, the portion of the insulating resin body 40 that is electrochemically coated in the insulating resin body coating process and that is located on the outer peripheral surface of the busbar group 20 contacts the underside of the portion of the frame body 30 that is located outward from the busbar group 20.

[0083] 12(a) and (b) show, respectively, a plan view of a busbar assembly 1C according to a second modified example of the present embodiment and a cross-sectional view taken along line XII(b)-XII(b) in FIG. 12(a).

[0084] Compared to the busbar assembly 1B of the first modified example, the busbar assembly 1C of the second modified example has a plurality of busbars 12 (first to third busbars 12(1) to 12(3)) instead of the plurality of busbars 10 (the first to third busbars 10(1) to 10(3)).

[0085] Among the side surfaces of the multiple busbars 12, side surface 12a which forms the outer peripheral surface of the busbar assembly 1C is an inclined surface that approaches the center of the busbar assembly 1C in a planar view as it moves from one side (the upper surface side) in the thickness direction to the other side (the lower surface side).

[0086] At least one of the opposing side surfaces 12b of the plurality of bus bars 12 may be an inclined surface. As shown in FIG. 12(b), in the second modified example 1C, both of the opposing side surfaces 12b of the plurality of bus bars 12 are inclined surfaces. In the second modified example 1C shown in FIG. 12(b), the opposing side surfaces 12b are inclined so that the width of the gap increases as one moves from one side in the thickness direction to the other side. Alternatively, as shown in FIG. 12(c), the opposing side surfaces 12b can be inclined so that the width of the gap 19 decreases as one moves from one side in the thickness direction to the other side.

[0087] 13(a) and (b) show, respectively, a plan view of a busbar assembly 1D according to a third modified example of the present embodiment and a cross-sectional view taken along line XIII(b)-XIII(b) in FIG. 13(a).

[0088] In the third modified example 1D, as shown in FIG. 13(b), the frame body 30 is disposed so that its outer circumferential surface is located inside the outer edge of the busbar group 20.

[0089] 14(a) and (b) respectively show a plan view of a busbar assembly 1E according to a fourth modified example of the present embodiment and a cross-sectional view taken along line XIV(b)-XIV(b) in FIG. 14(a).

[0090] The busbar assembly 1E according to the fourth modified example has a frame body 50 instead of the frame body 30, as compared with the busbar assembly 1A according to the present embodiment.

[0091] As shown in Figures 14(a) and (b), the frame body 50 has an inner frame portion 52 located on the inside when viewed in a plane, and an outer frame portion 55 surrounding the inner frame portion 52 while leaving a gap 53 when viewed in a plane.

[0092] In the fourth variant 1E including the frame body 50, the insulating resin body 40 is also provided on the portion of the upper surface of the multiple busbars 10 exposed by the gap 53 between the inner frame portion 52 and the outer frame portion 55 by electrochemical coating in the insulating resin body coating process.

[0093] At least one of the opposing side surfaces of the inner frame portion 52 and the outer frame portion 55 may be inclined so that the width of the gap 53 narrows from one side to the other side in the thickness direction. In the fourth variant example 1E, as shown in FIG. 14(b), both the opposing side surfaces of the inner frame portion 52 and the outer frame portion 55 are inclined so that the width of the gap 53 narrows from one side in the thickness direction to the other side.

[0094] Alternatively, as shown in Figure 14(c), at least one of the opposing side surfaces of the inner frame portion 52 and the outer frame portion 55 (in Figure 14(c), both of the opposing side surfaces of the inner frame portion 52 and the outer frame portion 55) can be inclined so that the width of the gap 53 increases from one side to the other in the thickness direction.

[0095] The configuration of the second variant 1C, i.e., the configuration in which the side 12a of the multiple busbars 12 that forms the outer peripheral surface of the busbar assembly 1C is an inclined surface, and / or the configuration in which the opposing side 12b of the multiple busbars 12 is an inclined surface, can also be applied to configurations other than the first variant, i.e., the busbar assemblies 1A, 1D, and 1E relating to the present embodiment, the third variant, and the fourth variant.

[0096] Embodiment 2 Hereinafter, another embodiment of the bus bar assembly according to the present invention will be described with reference to the accompanying drawings. In the following drawings of this embodiment, the same members as those in the first embodiment are given the same reference numerals, and the description thereof will be omitted as appropriate.

[0097] 15(a) and (b) show a plan view of a busbar assembly 2A according to this preferred embodiment and a cross-sectional view taken along line XV(b)-XV(b) in FIG. 15(a), respectively. FIG. 16 shows a vertical cross-sectional view of an example of a semiconductor module 102 in which a semiconductor element 110 such as an LED is mounted on the bus bar assembly 2A.

[0098] As shown in Figures 15(a), 15(b) and 16, the busbar assembly 2A of this embodiment comprises a single busbar 10, the frame body 30, a conductive connection terminal 60 provided on the frame body 30, and the insulating resin body 40.

[0099] The frame 30 is fixed to the upper surface of the bus bar 10 so as to fit along the peripheral edge of the bus bar 10 in a plan view.

[0100] As shown in FIG. 16, the connection terminal 60 is fixed to the frame body 30 by adhesive or the like at a position accessible from the outside, with sealing resin 130 arranged therein and prevented from flowing out by the frame body 30.

[0101] That is, in the busbar assembly 2A, the single busbar 10 acts as a first electrode which is one of the positive electrode and the negative electrode (e.g., the positive electrode), and the connection terminal 60 acts as a second electrode which is the other of the positive electrode and the negative electrode (e.g., the negative electrode). The connection terminal 60 is made of a conductive metal such as Cu.

[0102] As shown in Figures 15(a), 15(b) and 16, the insulating resin body 40 is provided with the upper surface exposing portion and the lower surface exposing portion that expose the upper surface and the lower surface of the bus bar 10, respectively.

[0103] As in the first embodiment, the upper surface exposing portion has a resin body opening 40a that exposes a predetermined area of ​​the upper surface of the busbar 10 within the central opening 35 of the frame body 30, and the lower surface exposing portion is configured to expose the entire lower surface of the busbar 10.

[0104] Hereinafter, an example (second manufacturing method) of the manufacturing method of the bus bar assembly 2A will be described. FIG. 17 shows a plan view of a conductive metal plate 300 for bus bars used in the second manufacturing method.

[0105] The second manufacturing method includes a step of preparing a busbar forming plate 300 having a busbar forming region 310 that has the same shape and thickness as the busbar 10 in a plan view.

[0106] In this embodiment, as shown in FIG. 17 , the busbar flat plate 300 has a busbar row 305 including a plurality of busbar forming regions 310 arranged in series along the Y direction in the XY plane in which the busbar flat plate 300 is located, and a connecting region 330 connecting adjacent busbar forming regions 310 in the Y direction, so that processing can be performed simultaneously on the plurality of busbar forming regions 310.

[0107] In this embodiment, the conductive metal plate 300 for busbars has a pair of gripping pieces 307 respectively connected to one side and the other side of the longitudinal direction (Y direction) of the busbar row 305, and alignment holes 308 are provided in the pair of gripping pieces 307.

[0108] It is also possible to arrange a plurality of busbar rows 305 in parallel in the X direction, and to integrally hold the plurality of busbar rows 305 arranged in parallel in the X direction by the pair of gripping pieces 307, 307. According to this modified configuration, a larger number of bus bar assemblies 2A can be manufactured at the same time.

[0109] The second manufacturing method includes a frame forming step of forming the frame 30 along the periphery of the busbar forming region 310 in a plan view by insert molding an insulating resin.

[0110] 18 and 19 are a plan view and a cross-sectional view taken along line XIX-XIX in FIG. 18, respectively, of the conductive metal plate 300 for bus bars after the frame body forming step.

[0111] The frame body forming process is configured to place the busbar assembly forming area 310 in a mold (not shown) that defines a frame body forming space, inject an insulating resin such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) or the like into the frame body forming space, and then harden the insulating resin by heat treatment or the like to form the frame body 30 fixed to the upper surface of the busbar assembly forming area 310. 15(b) and 19 denotes a mounting recess for mounting the connection terminal 60. As shown in FIG.

[0112] The second manufacturing method includes, after the frame body forming step, an insulating resin body coating step of providing the insulating resin body 40 on the outer surface of the bus bar assembly forming region 310 by electrodeposition coating.

[0113] 20 and 21 show a plan view and a cross-sectional view taken along line XXI-XXI in FIG. 20 of the conductive metal plate 300 for bus bars after the insulating resin body covering step, respectively.

[0114] The insulating resin body 40 is provided by electrochemically coating an insulating resin material (preferably Insulead (registered trademark)) having heat resistance and insulating properties such as polyamideimide, polyimide, polyamide, epoxy, etc. in the busbar forming region 310 where the insulating frame body 30 is provided, so that the insulating resin body 40 made of the insulating resin material is provided over the entire outer surface of the busbar forming region 310 that is exposed after the frame body is formed.

[0115] In other words, the boundary between the busbar forming region 310 and the frame body 30 is covered by the insulating resin body 40 produced by the insulating resin body coating process, thereby effectively preventing or reducing the occurrence of a gap between the busbar 10 and the frame body 30.

[0116] The second manufacturing method includes a connection terminal providing step of providing the connection terminal 60 on the outer surface of the frame 30 after the insulating resin covering step.

[0117] The connection terminal installation step is configured to, for example, fix the connection terminal 60 to the mounting recess 38 by adhesion.

[0118] The second manufacturing method further includes a busbar exposure process including an upper surface exposure process that exposes at least a portion of the upper surface of the busbar forming region 310 that is surrounded by the frame body 30, and a lower surface exposure process that exposes at least a portion of the lower surface of the busbar forming region.

[0119] The bus bar exposing step is performed after the insulating resin covering step and before the connection terminal installing step, or after the connection terminal installing step.

[0120] As in the first embodiment, in the present embodiment, the bus bar exposing step is configured to irradiate the portion to be exposed with laser light.

[0121] 22(a) and (b) are schematic vertical cross-sectional views of the lower surface exposing process and the upper surface exposing process, respectively. In addition, the symbol L in Figures 22(a) and (b) denotes laser light.

[0122] As described above, the lower surface exposed portion of the bus bar assembly 2A is configured to expose the entire lower surface of the bus bar 10. Therefore, in this embodiment, as shown in FIG. 22(a), the lower surface exposing process is configured to expose the entire lower surface of the busbar forming region 310.

[0123] In the present embodiment, the upper surface exposing process is configured to form the resin body opening 40a in the insulating resin body 40, as shown in FIG. 22(b).

[0124] The second manufacturing method further includes a cutting step of cutting the bus bar assembly forming region 310 from the conductive metal plate 300 for bus bars.

[0125] The cutting step is configured to cut the bus bar assembly forming region 310 along cutting lines C1 and C2 that respectively extend along edges on one side and the other side in the Y direction, as shown in FIG.

[0126] In the present embodiment, the cutting step is performed after the bus bar exposing step. Alternatively, the cutting step can be performed at any timing after the insulating resin covering step and before the bus bar exposing step. In this case, the bus bar exposing step and / or the connection terminal installing step is performed after the cutting step. [Explanation of symbols]

[0127] 1A~2A Busbar Assembly 10 Busbar 10(1)~10(3) 1st~3rd busbars 19 Gap 30, 50 frame 40 Insulating resin body 40(1)~40(3) 1st~3rd resin body openings 40a Resin body 52 Inner frame 55 Outer frame 60 Connection terminal 200, 300 Conductive metal plate for busbar 210, 310 Busbar assembly forming area L Laser light

Claims

1. a plurality of conductive bus bars arranged in the same plane with a gap between opposing sides; a frame body made of insulating resin and having an annular shape in a plan view, the frame body being fixed to upper surfaces of the plurality of bus bars so as to follow a peripheral edge in a plan view of a bus bar group defined by the plurality of bus bars arranged with the gaps therebetween; an insulating resin body that is electrodeposited on the outer surfaces of the plurality of bus bars; The busbar assembly is characterized in that the insulating resin body has an upper surface exposed portion and a lower surface exposed portion that expose the upper surfaces of the plurality of busbars on one thickness direction side and the lower surfaces of the plurality of busbars on the other thickness direction side, respectively.

2. 2. The bus bar assembly according to claim 1, wherein a boundary between each of the plurality of bus bars and the frame body is covered with the insulating resin body.

3. The busbar assembly according to claim 1 or 2, characterized in that the frame body has an inner frame portion located on the inside in a planar view, and an outer frame portion surrounding the inner frame portion with a gap therebetween in a planar view.

4. The busbar assembly according to claim 3, wherein at least one of the opposing side surfaces of the inner frame portion and the outer frame portion is inclined so that the width of the gap narrows from one side to the other side in the thickness direction.

5. 4. The busbar assembly according to claim 3, wherein at least one of the opposing side surfaces of the inner frame portion and the outer frame portion is inclined so that the width of the gap becomes wider from one side to the other side in the thickness direction.

6. The busbar assembly according to claim 2, characterized in that the frame body is arranged so that its inner circumferential surface overlaps with the busbar group in a planar view and at least a portion of its outer circumferential surface is positioned outward from the busbar group in a planar view.

7. The busbar assembly according to claim 6, characterized in that the side surfaces of the busbar that form the outer peripheral surface of the busbar assembly are inclined surfaces that approach the center of the busbar assembly in a planar view as they move from one side to the other side in the thickness direction.

8. 8. The bus bar assembly according to claim 6, wherein at least one of the opposing side surfaces of the plurality of bus bars is an inclined surface.

9. The bus bar assembly according to claim 1 or 2, wherein the frame is disposed such that an outer peripheral surface of the frame is positioned inside an outer edge of the bus bar group.

10. The bus bar assembly according to claim 9 , wherein at least one of the opposing side surfaces of the plurality of bus bars is an inclined surface.

11. A method for manufacturing a bus bar assembly including a plurality of conductive bus bars arranged in the same plane with a gap between opposing side surfaces, and an insulating frame body having an annular shape in a plan view and fixed to upper surfaces of the plurality of bus bars, comprising: preparing a conductive metal flat plate for busbars, the conductive metal flat plate having a busbar assembly forming region having the same outer shape in a plan view as a busbar group defined by the plurality of busbars arranged with the gaps being present; a slit forming step of forming one or more slits in the bus bar assembly forming region, the slits penetrating between the upper surface and the lower surface and having the same width as the gap, to form a plurality of bus bar forming portions corresponding to the plurality of bus bars; a frame forming step of forming the frame along a peripheral edge of the bus bar assembly forming region in a plan view by insert molding an insulating resin; an insulating resin body coating step of providing an insulating resin body on an outer surface of the bus bar assembly forming region by electrodeposition coating; a busbar exposing step of exposing at least a part of a portion of an upper surface of each of the plurality of busbar forming portions that is surrounded by the frame body and at least a part of a lower surface of each of the plurality of busbar forming portions; a cutting step performed after the busbar exposing step, or after the insulating resin body covering step and before the busbar exposing step, in which the busbar assembly formation area is cut from the conductive metal plate for the busbar.

12. A conductive bus bar; a frame body made of insulating resin and having an annular shape in a plan view, the frame body being fixed to an upper surface of the bus bar so as to follow a peripheral edge of the bus bar in a plan view; A conductive connection terminal provided on the frame body so as to be accessible from the outside; an insulating resin body that is electrodeposited on an outer surface of the bus bar, a busbar assembly, characterized in that the insulating resin body is provided with an upper surface exposing portion and a lower surface exposing portion that exposes an upper surface and a lower surface of the busbar, respectively;

13. A method for manufacturing a busbar assembly including a conductive busbar and an insulating frame provided on an upper surface of the busbar so as to fit along a peripheral region of the busbar in a plan view, the method comprising: preparing a conductive metal plate for a bus bar having a bus bar forming region for forming the bus bar; a frame forming step of forming the frame along a peripheral edge of the bus bar forming region in a plan view by insert molding an insulating resin; an insulating resin body coating step of providing an insulating resin body on an outer surface of the bus bar forming region by electrodeposition coating; a connection terminal installation step of providing a conductive connection terminal on an outer surface of the frame body; a busbar exposing step of exposing at least a part of an upper surface of the busbar forming region and at least a part of a lower surface of the busbar forming region, the busbar exposing step being performed after the insulating resin body covering step and before the connection terminal installation step or after the connection terminal installation step; and a cutting step of cutting the busbar forming region from the conductive metal flat plate for a busbar.

Images