Wiring module

Abstract

A wiring module is provided with a flexible printed circuit board provided with a land and wiring connected to the land, and a metal sheet having an upper surface, a lower surface, a through-hole, and an extension portion, the lower surface of the metal sheet being brazed to the land, the through-hole being formed in the upper surface of the metal sheet, and the extension portion being formed in the lower surface of the metal sheet. The metal sheet has a through-hole formed in the thickness direction of the metal sheet further toward the inside than the outer peripheral edge of the metal sheet, and a protruding portion formed so as to protrude from at least a part of the edge of the through-hole to the upper side than the upper surface of the metal sheet, the protruding portion having a plating layer forming portion and a plating layer non-forming portion. The plating layer forming portion is provided on an inner circumferential surface of the protruding portion facing the through hole, and the plating layer non-forming portion is provided on an end surface of a protruding end of the protruding portion.

Description

Cross - reference to related applications This application claims the priority of Japanese Patent Application No. 2023 - 217044, filed with the Japan Patent Office on December 22, 2023, and the entire contents of the said Japanese patent application are incorporated herein by reference. Technical field

[0001] The present invention relates to a wiring module including a flexible printed circuit board. Background art

[0002] Japanese Patent Laid - Open Publication No. 2022 - 114561 describes soldering a metal sheet (described as a metal plate in Japanese Patent Laid - Open Publication No. 2022 - 114561) to a land provided on a flexible printed circuit board. Thus, it is known to join a land of a flexible printed circuit board and a metal sheet by soldering such as brazing.

[0003] In addition, it is known that the metal sheet is formed of a material such as nickel or aluminum that easily forms a passivation film and a plating treatment is performed on the metal sheet. For example, sometimes tin plating is performed on a portion of the metal sheet connected to the land by solder as a plating layer having excellent solderability (that is, a soft coating film and a low melting point).

[0004] Moreover, an inspector visually confirms a fillet formed by brazing on this plating layer, and thereby determines whether brazing has been properly performed. Moreover, it is known to form a through - hole in the metal sheet and weld the inner peripheral surface of the through - hole to the land.

[0005] However, if the plating layer is continuously formed not only on the inner peripheral surface of the through - hole in the metal sheet but also on the surface of the metal sheet on the side opposite to the side facing the land, there is a case where a fillet is formed on the surface of the metal sheet on the side opposite to the side facing the land. In this case, the fillet formed on the inner peripheral surface (the portion facing the through - hole) of the through - hole, which is sometimes the object of the appearance inspection of brazing, becomes thin in thickness. Thus, the thickness of the fillet sometimes affects the appearance inspection of brazing (appearance inspection using visual, image, or X - ray). Therefore, in the prior art, there is room for improvement in improving the reliability of the appearance inspection of brazing. Summary of the invention

[0006] The present invention has been made in view of the above problems, and the present invention provides a wiring module capable of improving the reliability of the appearance inspection of brazing.

[0007] The wiring module of the present invention includes a flexible printed circuit board and a metal sheet. The flexible printed circuit board includes connection pads and wirings connected to the connection pads. The metal sheet has an upper surface, a lower surface, a through hole, and a protruding portion. The lower surface of the metal sheet is soldered to the connection pad. The through hole is formed along the thickness direction of the metal sheet inside the outer peripheral edge of the metal sheet. The protruding portion is formed to protrude from at least a part of the edge of the through hole to a position above the upper surface of the metal sheet. The protruding portion has a plating formation portion and a plating non-formation portion. The plating formation portion is provided on the inner peripheral surface of the protruding portion facing the through hole. The plating non-formation portion is provided on the end surface of the protruding end of the protruding portion.

[0008] According to the wiring module of the present invention, the reliability of the visual inspection of soldering can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a top view showing the wiring module of the first embodiment and a plurality of battery cells connected to the wiring module. Figure 2 It is a top view showing a state where the end of the extension portion of the flexible printed circuit board is connected to the protruding portion of the metal plate. Figure 3 It is an explanatory view schematically showing a state where the flexible printed circuit board is connected to the metal plate, and is a view showing the protruding portion provided on the metal sheet. Figure 4 It shows Figure 3 The end view of the protruding portion and the fillet in the IV-IV cross section of. Figure 5 It is an end view of the protruding portion and the fillet of the first modification, and is a view corresponding to Figure 4 corresponding. Figure 6 It is an end view of the protruding portion and the fillet of the second modification, and is a view corresponding to Figure 4 corresponding. Figure 7 It shows Figure 3 The cross-sectional view of the protruding portion of the third modification in the IV-IV cross section of. Figure 8 It is a perspective view showing the protruding portion and the through hole of the second embodiment. Figure 9 It shows Figure 8 The end view of the protruding portion and the fillet in the IX-IX cross section of. DETAILED DESCRIPTION OF THE INVENTION In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown schematically in order to simplify the drawing.

[0010] Hereinafter, a wiring module according to an embodiment of the present invention will be described with reference to the drawings. In addition, the embodiments described below are merely examples for facilitating understanding of the present invention, and do not limit the present invention. That is, the shape, size, configuration, etc. of the components described below can of course be changed and improved without departing from the gist of the present invention, and equivalents thereof are of course included in the present invention.

[0011] In addition, the drawings used in the present embodiment are diagrams for illustrating the configuration, shape, and arrangement of the components constituting the wiring module of the present invention, and do not limit the present invention. In addition, the drawings used in the present embodiment do not necessarily accurately represent the dimensional ratios such as the length, width, and height of the wiring module. In addition, in the drawings used in the present embodiment, the same reference numerals are given to the same components, and there are cases where the description is appropriately omitted.

[0012] <First Embodiment> <Overview> First, taking the wiring module 100 of the first embodiment as an example, mainly with reference to Figures 1 to 4 the overview of the present invention will be described. Figure 1 is a top view showing the wiring module 100 of the first embodiment and a plurality of battery cells 70 connected to the wiring module 100. Figure 2 is a top view showing a state where an end portion 15 of an extension portion 12 of the flexible printed circuit board 10 is connected to a protruding portion 22 of the metal plate 20. Figure 3 is an explanatory diagram schematically showing a state where the flexible printed circuit board 10 is connected to the metal plate 20, and is a view showing an extension portion 25 provided on the metal plate 20. Figure 4 is showing Figure 3 a front view of the extension portion 25 and the fillet 18a in the IV-IV cross section of

[0013] In addition, in Figure 1 the illustration of the fixing member for fixing the metal plate 20 to the battery cell 70 is omitted. In addition, Figure 2 a single metal plate 20 and an end portion 15 of a single extension portion 12 of the flexible printed circuit board 10 corresponding to the single metal plate 20 are enlarged and shown. In addition, Figure 3This is a figure mainly for explaining the protruding portion 25 provided at the connecting portion between the flexible printed circuit board 10 and the metal plate 20. A part of the metal plate 20 ( Figure 1 the protruding portion 22) and a part of the flexible printed circuit board 10 (the end portion 15) are cut out for explanation. In Figure 3 , the thickness of the plating layer is shown thicker than the actual thickness.

[0014] As Figure 1 and Figure 2 shown, the wiring module 100 of the first embodiment includes: a flexible printed circuit board 10 having a plurality of wirings 17 (refer to Figure 2 ) and a plurality of land portions 16; and a plurality of metal pieces (metal plates 20). One corresponding end of each of the plurality of wirings 17 is connected to each of the plurality of land portions 16. The metal plates 20 are overlapped and arranged on the land portions 16 and are brazed to the land portions 16. The metal plate 20 has an upper surface and a lower surface on the side opposite to the upper surface in the thickness direction, and the lower surface of the metal plate 20 is brazed to the land portion 16. As Figures 2 to 4 shown, the metal plate 20 has a protruding portion 25. Inside the outer peripheral edge 20a of the metal plate 20, the protruding portion 25 and the through hole 24 are formed in the thickness direction. The protruding portion 25 is formed to protrude in the thickness direction from at least a part of the edge of the through hole 24 to the side opposite to the side where the metal plate 20 is brazed to the land portion 16. Specifically, the protruding portion 25 is formed to protrude from at least a part of the edge of the through hole 24 to a position above the upper surface of the metal plate 20. In the present embodiment, the protruding portion 25 is formed by bending a part of the metal plate 20 upward. In Figure 3 the example shown, the protruding portion 25 protrudes from the entire edge of the through hole 24 (the entire circumference of the inner peripheral surface of the protruding portion 25) to a position above the upper surface of the metal plate 20, but the present invention is not limited thereto. The protruding portion 25 may also protrude from at least a part of the edge of the through hole 24 to a position above the upper surface of the metal plate 20. As Figure 4 shown, a plating layer forming portion 25a and a non - plating layer forming portion 25b are provided on the surface of the protruding portion 25. The plating layer forming portion 25a is arranged on the inner wall portion 25c of the inner peripheral surface of the protruding portion 25 facing the through hole 24, and the non - plating layer forming portion 25b is arranged on the end surface 25d of the protruding end of the protruding portion 25. In other words, in the present embodiment, the plating layer forming portion 25a is provided on the inner peripheral surface of the protruding portion 25 (the surface on the through hole 24 side of the protruding portion 25). The non - plating layer forming portion 25b is provided on the upper surface of the protruding end of the protruding portion 25. In the following description, there is Figure 4In the case where the upper side in an isometric view is referred to as one side and the lower side is referred to as the other side.

[0015] The metal plate 20 as the "metal sheet" in the present invention may be a bus bar that serially connects a plurality of battery cells 70, or may be a metal tab (not shown) that is an intermediate member connected to the bus bar. In the present embodiment, an example in which the metal plate 20 is a bus bar will be described. In addition, the "metal sheet" does not need to be entirely flat as long as there is a flat portion on the metal sheet at the portion brazed to the connection pad 16. Further, the metal sheet of the present invention is not limited to being related to the bus bar connected to the battery cell 70, and may also be connected to a conductive member (such as a wire) different from the bus bar.

[0016] In addition, the "brazing" in the present invention includes soft soldering and hard soldering. In the present embodiment, soft soldering will be described as an example.

[0017] As described above, at least a part of the edge of the through hole 24 in the metal sheet (metal plate 20) forms a protruding portion 25, the plating formation portion 25a is disposed on the inner wall portion 25c of the inner peripheral surface where the protruding portion 25 is formed, and the plating non-formation portion 25b is disposed on the end surface 25d of the protruding end. With such a configuration, as Figure 4 shown, the fillet 18a can be concentrated (aggregated) on the inner wall portion 25c of the inner peripheral surface where the protruding portion 25 is formed. Therefore, the fillet 18a can be easily detected in the appearance inspection. In addition, for the appearance inspection of the brazing of the fillet 18a, in addition to inspecting with an image inspection device, it can also be visually inspected by an inspector or inspected with an X-ray inspection machine.

[0018] In addition, assuming that the protruding portion 25 is not provided as in Figure 3 and Figure 4 but the protruding portion 25 is formed by bending the outer peripheral edge 20a of the metal sheet (metal plate 20) shown in Figure 2 , it is necessary to make the connection pad 16 one size larger than the joint portion of the metal plate 20 and the connection pad 16 in order to confirm the fillet 18a by visual inspection or the like. In contrast, as Figure 3 and Figure 4 shown, in the case where the protruding portion 25 is provided at the edge of the through hole 24 formed in the metal plate 20 and the fillet 18a is formed, the size relationship between the metal plate 20 and the connection pad 16 can be arbitrarily set, so the design freedom is improved.

[0019] The present embodiment will be described in more detail below. As Figure 1 shown, the wiring module 100 includes a flexible printed circuit board 10 and a plurality of metal plates 20, and a plurality of battery cells 70 are serially connected through these metal plates 20. The battery cell 70 is a secondary battery.

[0020] In the flexible printed circuit board 10 of the present embodiment, for example, wirings 17 are connected to a bus bar (metal plate 20) connected to a plurality of battery cells 70 to monitor voltage. For example, a connector is mounted on the flexible printed circuit board 10, and the flexible printed circuit board 10 is connected to a measuring device that performs various controls through the connector, so that the voltage can be monitored. As Figure 1 shown, the flexible printed circuit board 10 includes a flat plate-shaped main body portion 11 and a plurality of extending portions 12 extending from the edge of the main body portion 11.

[0021] The shape of the extending portion 12 is not particularly limited. As an example, as Figure 1 shown, it has a buckled shape in a top view. The extending portion 12 has an end portion 15 at its front end. The end portion 15 is formed to be wider than the portion on the base end side of the extending portion 12 in a top view. As an example, in the present embodiment, the entire extending portion 12 is arranged on the same plane. The planar shape of the end portion 15 is not particularly limited. As an example, in the present embodiment, it is rectangular (for example, a rounded rectangle).

[0022] As Figure 2 and Figure 4 shown, a connection pad 16, which is a thin film of a conductor such as metal, is formed on the upper surface of the end portion 15. The planar shape of the connection pad 16 is not particularly limited. As an example, it is rectangular (for example, a rounded rectangle). In the case of the present embodiment, the area of the connection pad 16 is smaller than the area of the protruding portion 22 of the metal plate 20. As Figure 2 shown, when viewed in the thickness direction of the metal plate 20 (in a top view), the connection pad 16 is housed inside the outer contour line (outer peripheral edge 20a of the metal plate 20) of the protruding portion 22 of the metal plate 20.

[0023] In addition, in the present embodiment, the connection pad 16 is formed without a gap in a region including the through hole 24 in a top view so as to cover the upper surface of the end portion 15 of the flexible printed circuit board 10. With such a configuration, the formation region of the fillet 18a can be limited to the formation region of the connection pad 16. When the metal plate 20 and the connection pad 16 are solder-bonded, the surface tension of the molten solder 18 can naturally and favorably control the positional accuracy of the metal plate 20 relative to the connection pad 16. However, the present invention is not limited to such a configuration, and a part of the connection pad 16 may not be formed in the region including the through hole 24 in a top view.

[0024] The flexible printed circuit board 10 includes a plurality of wirings 17. The plurality of wirings 17 extend from the main body portion 11 to the end portions 15 of the respective extending portions 12 (refer to Figure 2)。For example, one wiring 17 is arranged on each of the extension portions 12. One connection pad 16 is formed on each of the end portions 15, and the front end of each wiring 17 is connected to the corresponding connection pad 16.

[0025] The metal plate 20 of the present embodiment is a bus bar for connecting a plurality of battery cells 70 in series, and is formed in a flat plate shape, for example. As Figure 2 shown, the metal plate 20 has a main body portion 21 and a protruding portion 22, for example. The protruding portion 22 protrudes from the main body portion 21 in a plan view. In Figure 2 the example shown, in a plan view, the protruding portion 22 protrudes from the surface of the main body portion 21 along the long side direction to the outside of the main body portion 21. The dimension of the protruding portion 22 in the direction along the long side direction of the main body portion 21 is smaller than the dimension of the main body portion 21 in the long side direction. The planar shape of the main body portion 21 of the metal plate 20 is not particularly limited, and is a rectangle (for example, a rectangle with rounded corners) as an example. The main body portion 21 has two fixing holes 23. The two fixing holes 23 fix the main body portion 21 to two adjacent battery cells 70 respectively, and electrically connect the two battery cells 70 through the fixed main body portion 21. In addition, when the metal plate 20 is a metal tab connected to a bus bar, the metal plate 20 may not have the fixing holes 23.

[0026] The protruding portion 22 of the metal plate 20 is formed to protrude from the main body portion 21 in order to connect the metal plate 20 to the connection pad 16 provided on the flexible printed circuit board 10 by solder 18. The planar shape of the protruding portion 22 is not particularly limited, and is a rectangle (for example, a rectangle with rounded corners at the two corner portions on the front end side in the protruding direction) as an example. A through hole 24 is formed in the protruding portion 22, and a protruding portion 25 protruding upward from the edge of the through hole 24 is formed. The through hole 24 penetrates the protruding portion 22 of the metal plate 20 in the thickness direction.

[0027] The number of through holes 24 provided in each metal plate 20 is not particularly limited, but in the case of the present embodiment, one through hole 24 is formed in each metal plate 20 (each protruding portion 22 thereof). The planar shape of the through hole 24 is not particularly limited, but in the case of the present embodiment, it is circular, for example. However, the planar shape of the through hole 24 may also be rectangular, or may be any shape as described later. As Figure 4 shown, the connection pad 16 of each extension portion 12 and the protruding portion 22 of the corresponding metal plate 20 are joined by solder 18.

[0028] In Figure 3 the example shown, the protruding portion 25 is formed over the entire circumference of the edge of the through hole 24. In addition, in Figure 4In [the figure], the protruding portion 25 is shown as being bent at a right angle from another portion of the protruding portion 22 that is continuous with the base end side of the protruding portion 25 and protruding upward, but the present invention is not limited to such a configuration. For example, a bent portion can be formed at this bent portion. That is, of course, it can be bent and protrude upward instead of being bent at a right angle from the above-mentioned other portion. The same applies to the protruding portions 35, 45, 55, and 65 described later.

[0029] A partial plating treatment is performed on at least a part of the region in the metal plate 20 that can be the range connected to the flexible printed circuit board 10. As Figure 3 And Figure 4 As shown, the plating formation portion 25a is provided over the entire circumference of the inner peripheral surface of the protruding portion 25. As Figure 4 As shown, the non-plating formation portion 25b is provided over the entire circumference of the end face 25d of the protruding end that penetrates through the edge of the through hole 24.

[0030] As in the above configuration, the plating formation portion 25a where solder can be easily connected is provided over the inner peripheral surface of the protruding portion 25, and the non-plating formation portion 25b where solder is difficult to connect is provided over the entire circumference of the end face 25d of the protruding end, so that the fillet 18a can be easily formed in a ring shape. Therefore, the connection strength of brazing (soldering) can be further improved by the ring-shaped fillet 18a.

[0031] In addition, the plating formation portion 25a of the present embodiment is formed not only on the inner peripheral surface of the protruding portion 25 but also on the lower surface portion of the protruding portion 22 that is continuous with the inner peripheral surface of the protruding portion 25 (the portion that bears on the side of the land 16). In addition, the plating formation portion 25a is also formed on the outer peripheral surface of the protruding portion 25 and the upper surface portion of the protruding portion 22 that is continuous with the outer peripheral surface.

[0032] [First Modified Example] Figure 4 In [the figure], the protruding portion 25 of the above-described first embodiment is formed with an equal height, but the present invention is not limited to such a configuration. Next, with reference to Figure 5 The protruding portion 35 of the first modified example will be described. Figure 5 Is a plan view showing the protruding portion 35 and the fillets 38a and 38b of the first modified example, and is a figure corresponding to Figure 4 The corresponding figure.

[0033] As Figure 5 As shown, the portion 35f with the highest protruding height and the portion 35g with the lowest protruding height of the protruding portion 35 are provided in a relative manner. The positional relationship between the highest portion 35f and the lowest portion 35g is not limited to Figure 5 The example shown in [the figure]. As long as the lowest portion 35g and the highest portion 35f are in a top view (in Figure 3When observed in the thickness direction of the metal plate 20, it suffices to be provided on the opposite side with respect to the center of the through hole 24. Specifically, for the circular through hole 24, it suffices that the lowest portion 35g is within the range of +90 degrees or more and -90 degrees or less with respect to the highest portion 35f with the center of the through hole 24 as a reference. Further, when the through hole 24 and the protruding portion 25 are formed in a quadrilateral shape, it suffices that the highest portion 35f and the lowest portion 35g of the protruding portion 35 are located on one side and the other side of two opposite sides of the quadrilateral through hole 24, respectively. In addition, the circular through hole 24 is not limited to a perfect circle and may be an ellipse. The quadrilateral through hole 24 may also be a polygon with five or more sides.

[0034] According to the above configuration, by making the protruding heights of the protruding portions 35 different heights, it is possible to adjust the heights of the fillets 38a and 38b of the solder 38, and it is easy to adjust the connection strength according to the position of the edge of the through hole 24.

[0035] Specifically, at the portion of the inner wall portion 35c connected to the highest portion 35f of the protruding portion 35, the fillet 38a is formed in a relatively large range in the protruding direction, and at the portion of the inner wall portion 35c connected to the lowest portion 35g of the protruding portion 35, the fillet 38b is formed in a relatively small range in the protruding direction.

[0036] In addition, when viewed from above (observed in the thickness direction), the circular protruding portion 35 includes the highest portion 35f and the lowest portion 35g of the protruding portion 35, and is formed to have continuously different heights in the circumferential direction of the through hole 24. By forming in this way, the height of the entire fillet including the fillets 38a and 38b formed along the circular protruding portion 35 is easily continuously formed in the circumferential direction of the through hole 24, and thus it is easy to suppress stress concentration in the fillet.

[0037] [Second Modified Example] Figure 4 and Figure 5 It is shown in [FIG. XX] that the end surface 25d of the protruding portion 25 of the first embodiment and the end surface 35d of the protruding portion 35 of the first modified example are formed parallel to the upper surface of the protruding portion 22 and the upper surface of the connection pad 16, but the present invention is not limited to such a configuration. Next, with reference to Figure 6 the protruding portion 45 of the second modified example will be described. Figure 6 is an end view showing the protruding portion 25 and the fillet 18a of the second modified example, and is a view corresponding to Figure 4 FIG. XX.

[0038] As shown in Figure 6As shown, the end face 45d of the protruding end of the protruding portion 45 is formed to incline downward toward the center side of the through hole 24 and toward the other side (lower side) in the thickness direction. That is, the end face 45d of the protruding end inclines in such a manner that it approaches the upper surface of the connection disk 16 as it faces the center side of the through hole 24.

[0039] With the above configuration, even if the fillet 18a is temporarily disposed on the end face 45d where the plating non-formation portion 25b is provided on the protruding portion 45, since the end face 45d inclines downward, the self-weight of the fillet 18a is applied in the direction (lower side) toward the connection disk 16. Therefore, it is easy for the fillet 18a to move toward the plating formation portion 25a on the inner peripheral surface of the protruding portion 25.

[0040] In particular, in this modification example, the inner wall portion 45c of the protruding portion 45 is formed to incline toward the center side of the through hole 24 compared to the direction parallel to the thickness direction of the metal plate 20. By forming it in this way, compared with the case where the inner wall portion 45c of the protruding portion 45 extends in the direction parallel to the thickness direction of the metal plate 20, the interval between the plating formation portion 25a on the inner peripheral surface of the protruding portion 25 and the connection disk 16 becomes narrower, so that the bonding force of the fillet 18a can be improved. In addition, the downward inclination angle of the end face 45d of the protruding portion 45 with respect to the upper surface of the connection disk 16 can be made larger.

[0041] The inner wall portion 45c of the protruding portion 45 only needs to incline slightly toward the center side of the through hole 24 compared to the direction parallel to the thickness direction of the metal plate 20. In this way, if the inner wall portion 45c inclines, a formation region for the fillet 18a can be ensured in Figure 6 the vertical direction and the horizontal direction and the depth direction parallel to the upper surface of the protruding portion 22 other than the protruding portion 45, so it is preferable.

[0042] [Third Modification Example] The protruding portion 25 of the above-described first embodiment, the protruding portion 35 of the first modification example, and the protruding portion 45 of the second modification example may each form a groove 55i to be described below on their inner peripheral surfaces. Next, with reference to Figure 7 the protruding portion 55 of the third modification example will be described. Figure 7 is a cross-sectional view of the protruding portion 55 of the third modification example showing the IV-IV cross section of Figure 3 . In addition, in Figure 7 , the width of the groove 55i is shown enlarged for the sake of explaining the configuration.

[0043] As Figure 7 shown, a groove 55i is formed on the inner peripheral surface of the protruding portion 55. The groove 55i recesses from the inner peripheral surface side of the protruding portion 55 toward the outer peripheral surface side, and in the protruding direction ( Figure 7extends in the up-down direction). The depth of the recess of the groove 55i is formed to be shallower than the thickness of the plating formation portion 25a on the inner peripheral surface of the protruding portion 55.

[0044] The groove 55i is recessed and formed from the surface of the plating formation portion 25a toward the inside in the wall thickness direction of the protruding portion 55. The above-mentioned "extends in the protruding direction" means extending along the extending direction of the inner peripheral surface of the protruding portion 55, and is not limited to linearly extending in the protruding direction.

[0045] According to the above configuration, by forming the groove 55i on the inner peripheral surface of the protruding portion 55, the fillet 18a enters the groove 55i, thereby improving the connection strength between the fillet 18a and the metal plate 20. In addition, the recess of the groove 55i is formed shallower than the thickness of the plating formation portion 25a, thereby suppressing the exposure of the metal plate 20 from the plating formation portion 25a. In addition, as Figure 7 shown, if a plurality of grooves 55i are formed over the entire circumference of the inner peripheral surface of the protruding portion 55, the connection strength between the fillet 18a and the metal plate 20 can be uniformly improved over the entire inner peripheral surface of the protruding portion 55, and thus it is preferable.

[0046] In addition, in Figure 7 it is shown that the width of the groove 55i in the left-right direction is larger than the thickness of the plating formation portion 25a, but the configuration is not limited to this. The width of the groove 55i can also be formed to be the same as or smaller than the thickness of the plating formation portion 25a.

[0047] [Second Embodiment] Regarding the protruding portions 25, 35, 45 of the above first embodiment, an example in which the entire circumference of the edge of the through hole 24 formed in a circular shape when viewed from above protrudes upward has been described, but the present invention is not limited to such a configuration. Next, as the protruding portion 65 of the second embodiment, refer to Figure 8 and Figure 9 to describe the protruding portion 65 that protrudes upward from a part of the edge of the through hole 64. Figure 8 is a perspective view showing the protruding portion 65 and the through hole 64 of the second embodiment. Figure 9 is showing Figure 8 the end view of the protruding portion 65 and the fillet 18a in the IX-IX cross section.

[0048] The through-hole 64 of the present embodiment has an extension portion 64a. The extension portion 64a extends from the edge of the through-hole 64 toward the center side of the through-hole 64 in the surface direction of the metal sheet (metal plate 20). On both sides adjacent to the extension portion 64a of the through-hole 64, there are slits 64b formed along the extension direction of the extension portion 64a. A protruding portion 65 is formed at the extension end of the extension portion 64a. In addition, the above-mentioned "surface direction of the metal sheet (metal plate 20)" means any direction within a plane including Figure 9 the lateral direction and the depth direction.

[0049] Specifically, when the through-hole 64 of the present embodiment is viewed from above (observed in the thickness direction), it is formed in a vertically long C shape like Figure 8 shown. The two ends of the C shape of the through-hole 64 are the slits 64b, and the extension portion 64a is formed between the slits 64b. At the extension end of the extension portion 64a, a protruding portion 65 extending upward in the thickness direction is provided (refer to Figure 9 ).

[0050] The protruding portion 65 is formed at the extension end of the extension portion 64a, and compared with the case where it is formed in a manner of protruding from the edge of the through-hole 64 in the thickness direction without passing through the extension portion 64a, stress concentration can be suppressed when the protruding portion 65 is bent to one side in the thickness direction (the upper side in the example of Figure 9 ). For example, according to the configuration of the present embodiment, it is possible to suppress the generation of unillustrated wrinkled bulges due to stress concentration in the metal plate 20 near the slits 64b on both sides adjacent to the protruding portion 65.

[0051] However, the present invention is not limited to such a configuration, and the slits 64b may not be formed on both sides adjacent to the protruding portion 65. That is, the extension portion 64a extending from the edge of the through-hole 64 toward the center side of the through-hole 64 in the surface direction of the metal sheet may not be formed, and the protruding portion 65 may be formed in a manner of protruding directly upward from the edge of the through-hole 64.

[0052] In addition, the through-hole 64 has been described as a vertically long C shape of a square, but it may also be a quadrilateral or other shapes. In the through-hole 64 formed in this way, if the protruding portion 65 is formed from the edge portion in the long side direction of the edge of the through-hole 64, the formation region of the fillet 18a can be widely ensured, so it is preferred.

[0053] In addition, an example in which the protruding portion 65 is formed on a part (extension portion 64a) at the edge of the through hole 64 has been described, but the present invention is not limited thereto. The protruding portion 65 may also be formed on a plurality of parts at the edge of the through hole 64. With such a configuration, it is easy to form fillets 18a at the plurality of parts where the protruding portion 65 is formed. Therefore, the connection strength can be improved at the plurality of parts. In addition, it is possible to determine whether the welding is good at the plurality of parts.

[0054] Figure 9 The standing height H of the protruding portion 65 shown in is preferably in the range of 1.25 times or more and 5 times or less the thickness T of the metal sheet (metal plate 20). The above-mentioned "standing height H" refers to Figure 9 the height from the lower surface of the protruding portion 22 (the surface facing the connection pad 16) to the end face 65d of the protruding portion 65 as shown. With the above configuration, by limiting the standing height H of the protruding portion 65 to 1.25 times or more, the region for forming the fillet 18a can be sufficiently ensured. In addition, by limiting the standing height H of the protruding portion 65 to 5 times or less, it is possible to suppress the generation of a useless portion where the fillet 18a is not formed in the plating portion provided on the standing portion of the protruding portion 65.

[0055] In addition, it is preferable that the relationship between the standing height H of the protruding portion 65 and the thickness T of the metal plate 20 is the same as the relationship between the respective heights of the protruding portions 25, 35, the lowest portion 35g of the protruding portion 35, the protruding portion 45, and the protruding portion 55 in the first embodiment and the thickness T of the metal plate 20.

[0056] In addition, the various constituent elements of the wiring module 100 of the present invention may not exist independently. The present invention includes cases where a plurality of constituent elements are formed as one component, one constituent element is formed of a plurality of components, a certain constituent element is a part of another constituent element, and a part of a certain constituent element overlaps with a part of another constituent element.

[0057] This embodiment includes the following technical ideas. (1) A wiring module includes a flexible printed circuit board and a metal sheet. The flexible printed circuit board has connection pads and wirings connected to the connection pads. The metal sheet has an upper surface, a lower surface, a through hole, and a protruding portion. The lower surface of the metal sheet is soldered to the connection pad. The through hole is formed in the thickness direction of the metal sheet inside the outer peripheral edge of the metal sheet. The protruding portion is formed to protrude from at least a part of the edge of the through hole to a position above the upper surface of the metal sheet. The protruding portion has a plating formation portion and a non-plating formation portion. The plating formation portion is provided on the inner peripheral surface of the protruding portion facing the through hole. The non-plating formation portion is provided on the end surface of the protruding end of the protruding portion. (2) The wiring module according to (1), wherein the protruding portion is formed over the entire circumference of the edge of the through hole, the plating formation portion is provided over the entire circumference of the inner peripheral surface of the protruding portion, and the non-plating formation portion is provided over the entire circumference of the end surface of the protruding end of the protruding portion. (3) The wiring module according to (1) or (2), wherein the portion with the highest protruding height and the portion with the lowest protruding height of the protruding portion are arranged on opposite sides with respect to the center of the through hole in a top view. (4) The wiring module according to any one of (1) to (3), wherein the end surface of the protruding portion is inclined so as to approach the connection pad in the thickness direction as it faces the center side of the through hole. (5) The wiring module according to any one of (1) to (4), wherein a groove extending in the protruding direction of the protruding portion is formed on the inner peripheral surface of the protruding portion, and the groove is formed shallower than the thickness of the plating formation portion. (6) The wiring module according to (1) or (4) or (5) citing (1), wherein the through hole has an extension portion and a slit. The extension portion is provided to extend from the edge of the through hole toward the center side of the through hole. The slit is formed along the extension direction of the extension portion at adjacent positions on both sides of the extension portion. The protruding portion is formed at the extension end of the extension portion. (7) The wiring module according to any one of (1) to (6), wherein the standing height of the protruding portion in the thickness direction is in the range of 1.25 times or more and 5 times or less the thickness of the metal sheet. The standing height is the height from the lower surface of the metal sheet to the end surface of the protruding portion. The detailed description has been given for purposes of illustration and example. Many variations and modifications are possible in light of the above teachings. The detailed description is not without omissions or intended to limit the subject matter described herein. Although the subject matter has been described in terms of particular structural features and / or methodological processes, it is to be understood that the subject matter defined in the claims is not necessarily limited to the specific features or specific processes described. Rather, the specific features and specific processes are described as examples for implementing the claims.

Claims

1. A wiring module, characterized in that: The wiring module includes a flexible printed circuit board and a metal sheet. The flexible printed circuit board includes a connection pad and wiring connected to the connection pad. The metal sheet has an upper surface, a lower surface, a through hole and a protruding portion, The lower surface of the metal sheet is brazed to the connection pad, The through hole is formed inwardly of the outer peripheral edge of the metal sheet along the thickness direction of the metal sheet, The protruding portion is formed to protrude from at least a portion of the edge of the through hole to an upper side than the upper surface of the metal sheet. The protruding portion includes a plated layer forming portion and a plated layer non-forming portion. The plating layer forming portion is provided on the inner peripheral surface of the protruding portion facing the through hole, The plated layer non-forming portion is provided on an end surface of an extended end of the extended portion.

2. The wiring module according to claim 1, characterized in that: The protruding portion is formed over the entire circumference of the edge of the through hole, The plating layer forming portion is arranged over the entire circumference of the inner peripheral surface of the protruding portion, The plated layer non-formed portion is provided over the entire circumference of the end surface of the extended end of the extended portion.

3. The wiring module according to claim 1 or 2, characterized in that: The portion of the protruding portion where the protruding height is the highest and the portion where the protruding height is the lowest are arranged on opposite sides with respect to the center of the through hole in a plan view.

4. The wiring module according to claim 3, characterized in that: The end surface of the protruding portion is formed to be inclined so as to approach the connection land in the thickness direction toward the center side of the through hole.

5. The wiring module according to claim 1, characterized in that: The through hole has an extension portion and a gap, The extension portion is configured to extend from the edge of the through hole toward the center of the through hole. The slits are formed at adjacent locations on both sides of the extension portion along the extension direction of the extension portion. The protruding portion is formed at an extended end of the extending portion.

6. The wiring module according to claim 5, characterized in that: The rising height of the protruding portion in the thickness direction is in a range of not less than 1.25 times and not more than 5 times the thickness of the metal sheet, and the rising height is the height from the lower surface of the metal sheet to the end surface of the protruding portion.

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