Connection structure, reactor device, and method for manufacturing connection structure

Abstract

One embodiment of the present disclosure provides a connection structure with which it is possible to improve the reliability of quality assurance. This connection structure, which is provided to a reactor device (10), has a flat plate-shaped first connection part (51) that is provided to a bus bar (50), and a flat plate-shaped winding end part (33) that is provided to a coil (31). The first connection part and the winding end part are overlapped in a first direction (X1). The connection structure has a weld part (60) where the first connection part and the winding end part are welded, and an inclined surface (55) extending from the weld part (60) toward a second direction (Y1). The weld part (60) is provided to a third-direction (Z1) end part of the first connection part (51). The inclined surface (55) is provided to a corner between the end surface of the first connection part (51) that faces the winding end part (33) and the end surface of the first connection part (51) that faces the third direction (Z1). The inclined surface (55) is inclined toward a third opposite direction (Z2) to a greater extent with increasing proximity to the winding end part (33).

Description

Connection structure, reactor device and method for manufacturing connection structure

[0001] The present disclosure relates to a connection structure, a reactor device, and a method for manufacturing the connection structure.

[0002] Conventionally, vehicles such as automobiles have been equipped with electrical junction boxes for converters, etc. (See, for example, Patent Document 1.) This type of electrical junction box has a connection structure in which a first flat connection terminal and a second flat connection terminal are connected by welding.

[0003] Japanese Patent Application Laid-Open No. 2006-203976

[0004] In the above-described connection structure, it is desirable to improve the reliability of quality assurance for the welded portion. An object of the present disclosure is to provide a connection structure, a reactor device, and a method for manufacturing a connection structure that can improve the reliability of quality assurance.

[0005] The connection structure of the present disclosure comprises a flat first connection terminal, a flat second connection terminal overlapped with the first connection terminal in a first direction, a welded portion at which the first connection terminal and the second connection terminal are welded, and an inclined surface provided on the first connection terminal and extending from the welded portion toward a second direction intersecting the first direction, wherein the welded portion is provided on a portion of the first connection terminal in the second direction, and the welded portion is provided on an end of the first connection terminal in a third direction intersecting both the first direction and the second direction, and the inclined surface is provided at a corner between a first end face of the first connection terminal facing the second connection terminal and a second end face of the first connection terminal facing the third direction, and the inclined surface is formed so as to slope toward a third opposite direction, which is the opposite direction to the third direction, as it approaches the second connection terminal.

[0006] The connection structure of the present disclosure has the effect of improving the reliability of quality assurance.

[0007] FIG. 1 is a perspective view showing a reactor device of an embodiment. FIG. 2 is a perspective view showing an assembly of an embodiment. FIG. 3 is a plan view showing a part of the reactor device of an embodiment. FIG. 4 is a cross-sectional view (cross-sectional view taken along line 4-4 in FIG. 3) showing a part of the reactor device of an embodiment. FIG. 5 is a perspective view showing a part of the reactor device of an embodiment. FIG. 6 is a perspective view showing a manufacturing method of the reactor device of an embodiment. FIG. 7 is a diagram showing an example of an image captured by image inspection in the manufacturing method of the reactor device of an embodiment.

[0008] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be described. [1] A connection structure of the present disclosure includes a flat first connection terminal, a flat second connection terminal overlapping the first connection terminal in a first direction, a welded portion at which the first connection terminal and the second connection terminal are welded, and an inclined surface provided on the first connection terminal and extending from the welded portion toward a second direction intersecting the first direction, wherein the welded portion is provided on a part of the first connection terminal in the second direction, the welded portion is provided on an end of the first connection terminal in a third direction intersecting both the first direction and the second direction, the inclined surface is provided at a corner between a first end face of the first connection terminal facing the second connection terminal and a second end face of the first connection terminal facing the third direction, and the inclined surface is formed so as to incline toward a third opposite direction that is a direction opposite to the third direction as it approaches the second connection terminal.

[0009] According to this configuration, a flat first connection terminal and a flat second connection terminal are overlapped in the first direction, and the first connection terminal and the second connection terminal are joined to each other by a weld. Furthermore, the first connection terminal is provided with an inclined surface extending from the weld in the second direction. That is, the inclined surface is formed adjacent to the weld. In other words, the inclined surface is provided in the non-welded portion adjacent to the weld. This makes it easier to obtain contrast between the weld and the inclined surface when detecting the size of the weld using an imaging device. This makes it easier to recognize the boundary between the weld and the inclined surface (non-welded portion), allowing for accurate measurement of the size of the weld, for example, the width dimension of the weld along the second direction. This allows for accurate quality determination of the weld based on the measured width dimension of the weld. As a result, the reliability of quality assurance for the weld can be improved.

[0010] [2] In the above [1], the welded portion may be provided at an intermediate position of the first connection terminal in the second direction, and the inclined surface may extend from the welded portion toward the second direction and also extend from the welded portion toward a second opposite direction that is the opposite direction to the second direction.

[0011] According to this configuration, the inclined surfaces are formed so as to extend from the welded portion in both the second direction and the second opposite direction. That is, the inclined surfaces are formed adjacent to both sides of the welded portion. In other words, an inclined surface is formed in each of the non-welded portions adjacent to both sides of the welded portion. This makes it easier to identify the boundary between the welded portion and the inclined surfaces provided on both sides of the welded portion, allowing for more accurate measurement of the width dimension of the welded portion. Therefore, the quality of the welded portion can be determined more accurately based on the measured width dimension of the welded portion. As a result, the reliability of quality assurance for the welded portion can be further improved.

[0012] [3] In the above [1] or [2], the inclined surface may be formed only on the first connection terminal out of the first connection terminal and the second connection terminal. With this configuration, the inclined surface is formed only on the first connection terminal. This makes it possible to prevent the bonding area between the first connection terminal and the second connection terminal from becoming smaller than when inclined surfaces are formed on both the first connection terminal and the second connection terminal.

[0013] [4] In the above [3], the first connection terminal may have a thickness in the first direction, the second connection terminal may have a thickness in the first direction, and the thickness dimension of the first connection terminal may be greater than the thickness dimension of the second connection terminal.

[0014] According to this configuration, the inclined surface is formed only on the first connection terminal, which has the larger thickness dimension, of the first and second connection terminals, thereby preventing the volume of the second connection terminal, which has the smaller thickness dimension, from being reduced.

[0015] [5] In any of the above [1] to [4], the first connection terminal may have a thickness in the first direction, and the inclined surface may be formed so that its dimension along the third direction is larger than its dimension along the first direction.

[0016] According to this configuration, when the first connection terminal and the second connection terminal are overlapped in the first direction, a gap is formed between the first connection terminal and the second connection terminal by the inclined surface. Here, if the separation distance between the first connection terminal and the second connection terminal in the first direction becomes large, the quality of the welded portion is likely to deteriorate. In contrast, with the above configuration, the inclined surface is formed so that its dimension along the third direction is larger than its dimension along the first direction. This prevents the separation distance between the first connection terminal and the second connection terminal in the first direction from becoming large. Therefore, it is possible to prevent the quality of the welded portion from deteriorating.

[0017] [6] In any of the above [1] to [5], the inclined surface may be formed so as to be inclined at a constant inclination angle. With this configuration, when light is irradiated onto the inclined surface to detect the size of the weld, the light can be suitably diffusely reflected (scattered) by the inclined surface inclined at a constant inclination angle. This enhances the contrast between the weld and the inclined surface. As a result, the boundary between the weld and the inclined surface is more easily recognized, allowing for more accurate measurement of the width dimension of the weld.

[0018] [7] In any one of the above [1] to [6], the welded portion may be a portion where the first connection terminal and the second connection terminal are TIG-welded. This configuration improves the reliability of quality assurance for the welded portion welded by TIG welding.

[0019] [8] The reactor device of the present disclosure is a reactor device having a connection structure described in any one of [1] to [7] above, and includes a reactor having a coil and a core, and a bus bar electrically connected to the coil, the bus bar having the first connection terminal, and the coil having a winding portion formed by spirally winding a winding, and the second connection terminal which is a winding end of the winding portion.

[0020]

[0013] According to this configuration, it is possible to improve reliability of quality assurance for a welded portion at which a first connection terminal of a bus bar and a second connection terminal of a coil are welded. [9] A manufacturing method of a connection structure according to the present disclosure includes the steps of: preparing a flat first connection terminal having a first end surface; forming an inclined surface on the first end surface; preparing a flat second connection terminal; overlapping the first connection terminal and the second connection terminal in the first direction with the first end surface facing the second connection terminal in the first direction; and joining the first connection terminal and the second connection terminal by welding to form a welded portion and forming a structure having the inclined surface extending from the welded portion in a second direction intersecting the first direction. and a step of measuring a width dimension of the weld along the second direction by image inspection, wherein the weld is formed on a part of the first connection terminal in the second direction, the weld is formed on an end of the first connection terminal in a third direction that intersects both the first direction and the second direction, the inclined surface is formed at a corner between the first end face and a second end face of the first connection terminal facing the third direction, and the inclined surface is formed so as to incline toward a third opposite direction that is the opposite direction to the third direction as it approaches the second connection terminal.

[0021] According to this configuration, the first and second flat connection terminals are joined to each other by a welded portion while the first and second flat connection terminals are overlapped in the first direction. The first connection terminal also has an inclined surface extending from the welded portion toward the second direction. That is, the inclined surface is formed adjacent to the welded portion. In other words, the inclined surface is formed in the non-welded portion adjacent to the welded portion. Therefore, when detecting the welded portion using an imaging device during image inspection, the contrast between the welded portion and the inclined surface is easily obtained. Therefore, the boundary between the welded portion and the inclined surface (non-welded portion) is easily recognized, allowing the size of the welded portion, specifically the width dimension of the welded portion along the second direction, to be accurately measured. This allows for accurate quality determination of the welded portion based on the measured width dimension of the welded portion. As a result, the reliability of quality assurance for the welded portion can be improved.

[0022] [Details of the Embodiments of the Present Disclosure] Specific examples of connection structures and reactor devices of the present disclosure are described below with reference to the drawings. In each drawing, some components may be exaggerated or simplified for ease of explanation. Furthermore, the dimensional ratios of each component may differ between drawings. In this specification, "parallel" and "orthogonal" do not necessarily refer to strictly parallel or orthogonal relationships, but also include roughly parallel or orthogonal relationships within the scope of the present embodiment's effects. The term "cylindrical" used in this specification does not only refer to a structure having a continuous peripheral wall along the entire periphery, but also includes a structure formed by combining multiple components and a structure having a notch in the periphery, such as a C-shape or U-shape. The term "cylindrical" includes, but is not limited to, a circle, an ellipse, and a polygon with sharp or rounded corners. Furthermore, terms such as "first," "second," and "third" used in this specification are used simply to distinguish between objects and not to rank them. Each drawing illustrates mutually orthogonal X-, Y-, and Z-axes. Each drawing illustrates a first direction X1, which is a direction in the X-axis direction along the X-axis, and a first opposite direction X2, which is the opposite direction of the first direction X1. Each drawing illustrates a second direction Y1, which is a direction in the Y-axis direction along the Y-axis, and a second opposite direction Y2, which is the opposite direction of the second direction Y1. Each drawing illustrates a third direction Z1, which is a direction in the Z-axis direction along the Z-axis, and a third opposite direction Z2, which is the opposite direction of the third direction Z1. Note that the present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0023] 1 is used as a component of a converter mounted on a vehicle such as an electric vehicle or a hybrid vehicle, or as a component of a power conversion device having such a converter. Examples of the converter include a DC-DC converter and an AC-DC converter.

[0024] The reactor device 10 includes a reactor 20 and a bus bar 50. The reactor 20 includes an assembly 30 including a coil 31, and an insulating member 40. (Configuration of the assembly 30) As shown in Fig. 2 , the assembly 30 includes the coil 31 and a core 35.

[0025] (Configuration of coil 31) The coil 31 has one or more winding portions 32 formed by winding a wire in a spiral shape. The coil 31 of this embodiment has one winding portion 32. A known winding can be used as the winding. The winding of this embodiment is a coated rectangular wire having a conductor wire and an insulating coating. The conductor wire is made of, for example, a rectangular wire made of copper or a copper alloy. The insulating coating is made of, for example, enamel. The winding portion 32 is formed, for example, by edgewise winding the coated rectangular wire. The winding portion 32 is formed in a cylindrical shape. The winding portion 32 of this embodiment is formed in a square cylindrical shape.

[0026] The coil 31 has winding end portions 33, 34. Each of the winding end portions 33, 34 is formed so as to be drawn out from the winding portion 32 toward the outer periphery of the winding portion 32. The winding end portions 33, 34 and the winding portion 32 are formed continuously and integrally. The insulating coating of each of the winding end portions 33, 34 is stripped to expose the conductor wire. As shown in FIG. 1 , each of the winding end portions 33, 34 is provided outside the insulating member 40. A bus bar 50 is joined to the winding end portion 33. A first connection portion 51 of the bus bar 50 is joined to the winding end portion 33 by welding. FIG. 1 illustrates only the bus bar 50 joined to the winding end portion 33, and does not illustrate the bus bar joined to the winding end portion 34. The configuration of the bus bar connected to the winding end portion 34 may be the same as or different from that of the bus bar 50. The coil 31 is electrically connected to an external device (not shown) through the bus bar 50. An example of the external device is a power supply that supplies power to the coil 31 .

[0027] (Configuration of Core 35) As shown in Fig. 2, the core 35 has an inner core portion 36 arranged inside the winding portion 32 of the coil 31, and an outer core portion 37 arranged outside the winding portion 32. The inner core portion 36 is formed to extend along the axial direction of the winding portion 32 (here, the Y-axis direction). The outer core portion 37 is formed to surround the outer periphery of the winding portion 32. The core 35 is formed, for example, by a plurality of parts.

[0028] The core 35 is a magnetic body in which a closed magnetic circuit is formed. The core 35 is made of, for example, a powder compact or a composite material compact. The powder compact is formed by pressing raw material powder containing soft magnetic powder. Examples of the soft magnetic powder material include pure iron and iron alloys. The composite material compact is formed by filling a mold with a mixture of soft magnetic powder and unsolidified resin and solidifying the resin. In the composite material compact, the soft magnetic powder is dispersed in the resin.

[0029] (Configuration of the Insulating Member 40) As shown in FIG. 1 , the insulating member 40 is formed to cover the outer periphery of the assembly 30. The insulating member 40 is formed to house the assembly 30. The insulating member 40 is formed to insulate the coil 31 from the core 35 (see FIG. 2 ). For example, the insulating member 40 is formed to integrate the coil 31 and the core 35 (see FIG. 2 ). For example, the insulating member 40 has a function of determining the relative positions of the coil 31 and the core 35 (see FIG. 2 ). For example, the insulating member 40 has a function of protecting the assembly 30. The insulating member 40 of this embodiment does not cover a portion of the end surface of the winding portion 32 in the third direction Z1. In other words, the insulating member 40 is formed to expose a portion of the end surface of the winding portion 32 in the third direction Z1. As a result, heat generated in the coil 31 can be efficiently dissipated to the outside of the insulating member 40.

[0030] The insulating member 40 may be, for example, a resin molded member. The insulating member 40 may be made of, for example, a thermoplastic resin. Examples of the thermoplastic resin include polyphenylene sulfide (PPS) resin, polytetrafluoroethylene (PTFE) resin, liquid crystal polymer (LCP), and polyamide (PA) resin. Examples of the thermoplastic resin include polybutylene terephthalate (PBT) resin and acrylonitrile butadiene styrene (ABS) resin.

[0031] The insulating member 40 has, for example, a terminal block 41. The second connection portion 52 of the bus bar 50 is provided on an end surface of the terminal block 41 in the third direction Z1. The terminal block 41 has bolt holes 41X into which bolts (not shown) are inserted. The terminal block 41 is a base for supporting a connection terminal of an external device (not shown). Although not shown, the connection terminal of the external device is bolted to the terminal block 41 in a state where it is overlapped with the second connection portion 52 of the bus bar 50 in the Z-axis direction. By bolting the connection terminal of the external device, the connection terminal is fixed to the terminal block 41 and electrically connected to the bus bar 50.

[0032] As shown in FIGS. 1 and 3 , the insulating member 40 has a support portion 42 that supports the bus bar 50. The support portion 42 is provided to support an intermediate portion 53 of the bus bar 50. In this embodiment, the support portion 42 is provided to support a portion of the intermediate portion 53 of the bus bar 50 that is close to the first connection portion 51. The support portion 42 is formed to protrude in the second direction Y1 from an end surface of the insulating member 40 in the second direction Y1. As shown in FIG. 3 , the support portion 42 has a support surface 43 that supports the intermediate portion 53 of the bus bar 50. The support surface 43 is a plane that faces the third direction Z1. The support surface 43 is, for example, a plane parallel to the XY plane.

[0033] As shown in FIG. 1 , the insulating member 40 is formed so as to expose the winding ends 33, 34 of the coil 31. The winding end 33 is formed so as to protrude from the outer surface of the insulating member 40 in the second direction Y1. The winding end 33 extends from the outer surface of the insulating member 40 in the second direction Y1 with its thickness direction oriented in the X-axis direction. The winding end 34 is formed so as to protrude from the outer surface of the insulating member 40 in the first opposite direction X2. The winding end 34 extends from the outer surface of the insulating member 40 in the first opposite direction X2 with its thickness direction oriented in the Y-axis direction.

[0034] The reactor 20 may have a holding member (not shown) that holds the coil 31 and the core 35 shown in FIG. 2 . The holding member is, for example, interposed between the end face of the winding portion 32 and the outer core portion 37, thereby insulating the coil 31 from the core 35. That is, the holding member constitutes a part of the insulating member 40. The holding member is made of a resin material. The resin material that constitutes the holding member may be, for example, the thermoplastic resin used for the insulating member 40. The insulating member 40 may be constituted only by the holding member.

[0035] 1, the bus bar 50 is a member that electrically connects the coil 31 to an external device (not shown). The bus bar 50 is formed of, for example, a metal with excellent conductivity. The bus bar 50 can be made of copper, a copper alloy, aluminum, or an aluminum alloy.

[0036] The bus bar 50 has a first connection portion 51, a second connection portion 52, and an intermediate portion 53 provided between the first connection portion 51 and the second connection portion 52. The bus bar 50 is a single component in which the first connection portion 51, the intermediate portion 53, and the second connection portion 52 are continuously and integrally formed.

[0037] The first connection portion 51 is a portion that is connected to the winding end portion 33 of the coil 31 in an overlapping state. The first connection portion 51 is provided, for example, at the end portion of the bus bar 50 in the first direction X1. The first connection portion 51 is formed, for example, so as to bend from the end portion of the intermediate portion 53 in the first direction X1 and extend toward the third direction Z1. The first connection portion 51 is formed in a flat plate shape. The first connection portion 51 of this embodiment is formed in a rectangular plate shape having a thickness in the first direction X1. That is, the thickness direction of the first connection portion 51 coincides with the first direction X1. The first connection portion 51 is formed to extend in both the Z-axis direction and the Y-axis direction. The first connection portion 51 is formed to protrude toward the second direction Y1 from the end portion of the intermediate portion 53 in the first direction X1. The dimension of the first connection portion 51 along the second direction Y1 is greater than the dimension of the intermediate portion 53 along the second direction Y1. The first end face of the first connection portion 51 facing the winding end portion 33, i.e., the end face facing the first direction X1, is formed in a plane parallel to the YZ plane. The end face of the first connection portion 51 facing the first direction X1 is formed to be able to come into surface contact with the end face of the winding end portion 33 facing the first opposite direction X2. Here, the winding end portion 33 in this embodiment is formed in a rectangular plate shape having a thickness in the first direction X1. In other words, the thickness direction of the winding end portion 33 coincides with the first direction X1. The end face of the winding end portion 33 facing the first connection portion 51, i.e., the end face facing the first opposite direction X2, is formed in a plane parallel to the YZ plane.

[0038] 4, the thickness of the first connection portion 51 is greater than the thickness of the winding end portion 33. That is, the dimension of the first connection portion 51 along the first direction X1 is greater than the dimension of the winding end portion 33 along the first direction X1.

[0039] As shown in Fig. 5, the first connection portion 51 and the winding end portion 33 are joined to each other by welding. In other words, the connection structure between the first connection portion 51 and the winding end portion 33 has a welded portion 60 where the first connection portion 51 and the winding end portion 33 are welded together. The welded portion 60 is formed by integrally joining the first connection portion 51 and the winding end portion 33. In each drawing, the welded portion 60 is illustrated with a matte finish. Note that examples of welding include TIG welding and resistance welding. In this embodiment, the first connection portion 51 and the winding end portion 33 are joined to each other by TIG welding.

[0040] The welded portion 60 is provided at a part of the first connection portion 51 in the second direction Y1. The welded portion 60 is provided, for example, at a middle position of the first connection portion 51 in the second direction Y1. In this embodiment, the welded portion 60 is provided at a central position of the first connection portion 51 in the Y-axis direction. The welded portion 60 is provided at an end of the first connection portion 51 in the third direction Z1. The welded portion 60 is formed to extend from the end of the first connection portion 51 in the third direction Z1 toward the third opposite direction Z2. In this embodiment, the welded portion 60 extends from the end of the first connection portion 51 in the third direction Z1 to a middle portion of the first connection portion 51 in the Z-axis direction. Similarly, the welded portion 60 is provided, for example, at a middle position of the winding end portion 33 in the second direction Y1. The welded portion 60 is formed to extend from the end of the winding end portion 33 in the third direction Z1 toward the third opposite direction Z2.

[0041] 4 and 5 , the first connection portion 51 has an inclined surface 55. The inclined surface 55 is provided on a first end surface of the first connection portion 51 facing the winding end portion 33, which is the end surface facing the first direction X1 in this embodiment. The inclined surface 55 is provided on a second end surface of the first connection portion 51 facing the third direction Z1. Specifically, the inclined surface 55 is provided at a corner between the first end surface of the first connection portion 51 facing the winding end portion 33 and the second end surface of the first connection portion 51 facing the third direction Z1.

[0042] As shown in FIG. 4 , the inclined surface 55 is formed so as to slope toward the third opposite direction Z2 as it approaches the winding end 33. Furthermore, the inclined surface 55 is formed so as to slope toward the first direction X1, i.e., toward the winding end 33, from the end of the inclined surface 55 in the third direction Z1 toward the end of the inclined surface 55 in the third opposite direction Z2. The inclined surface 55 of this embodiment is formed as a plane that slopes linearly in a cross-sectional view. That is, the inclined surface 55 of this embodiment is formed so as to slope at a constant inclination angle. For example, the inclined surface 55 is formed so as to chamfer the corner between the end face of the first connection portion 51 in the first direction X1 and the end face of the first connection portion 51 in the third direction Z1. For example, the inclined surface 55 is formed by cutting the corner between the end face of the first connection portion 51 in the first direction X1 and the end face of the first connection portion 51 in the third direction Z1.

[0043] The inclined surface 55 is formed, for example, so that the dimension along the third direction Z1 is larger than the dimension along the first direction X1. The inclined surface 55 is formed, for example, so that the dimension along the third direction Z1 is larger than the dimension along the first direction X1 by at least two times. For example, when forming the inclined surface 55, the cutting amount along the third direction Z1 is set to be larger than the cutting amount along the first direction X1.

[0044] When the end face of the first connection portion 51 in the first direction X1 and the end face of the winding end portion 33 in the first opposite direction X2 are in surface contact with each other, the inclined surface 55 forms a gap 56 between the first connection portion 51 and the winding end portion 33. The gap 56 is formed, for example, in the shape of a right triangle in cross section. The dimension of the gap 56 along the first direction X1 is smaller than the dimension of the gap 56 along the third direction Z1.

[0045] As shown in FIG. 5 , the inclined surface 55 extends from the welded portion 60 toward the second direction Y1. For example, the inclined surface 55 extends along the second direction Y1 from the welded portion 60 to the end of the first connection portion 51 in the second direction Y1. The inclined surface 55 also extends, for example, from the welded portion 60 toward the second opposite direction Y2. For example, the inclined surface 55 extends along the second opposite direction Y2 from the welded portion 60 to the end of the first connection portion 51 in the second opposite direction Y2. As such, the inclined surfaces 55 of this embodiment are provided on both sides of the welded portion 60 in the Y-axis direction. In other words, the welded portion 60 of this embodiment is formed so as to be sandwiched between the pair of inclined surfaces 55 in the Y-axis direction. The inclined surfaces 55 are provided on portions of the first connection portion 51 other than the welded portion 60, i.e., non-welded portions. The inclined surfaces 55 are provided only on the first connection portion 51 between the first connection portion 51 and the winding end portion 33.

[0046] As shown in FIG. 3 , the intermediate portion 53 is provided between the first connecting portion 51 and the second connecting portion 52. The intermediate portion 53 is formed to connect the first connecting portion 51 and the second connecting portion 52. The intermediate portion 53 extends along the X-axis direction as a whole. The intermediate portion 53 has, for example, a bent portion 53A that is bent in a crank shape. The bent portion 53A is bent, for example, in a crank shape on the XY plane. The bent portion 53A is provided, for example, in an end region of the intermediate portion 53 in the first direction X1. The bent portion 53A is placed on the support surface 43 of the support portion 42 of the insulating member 40.

[0047] The second connection portion 52 is provided, for example, at the end of the bus bar 50 opposite to the first connection portion 51. The second connection portion 52 is provided on the terminal block 41 of the insulating member 40. The second connection portion 52 is formed, for example, so as to bend from the end of the intermediate portion 53 in the first opposite direction X2 and extend in a first oblique direction intersecting both the first direction X1 and the second direction Y1. The second connection portion 52 is formed, for example, so as to bend from the end of the intermediate portion 53 in the first opposite direction X2 on the XY plane and extend in the first oblique direction. The second connection portion 52 is formed in a plate shape. In this embodiment, the second connection portion 52 is formed in a plate shape having a thickness in the third direction Z1. That is, the thickness direction of the second connection portion 52 coincides with the third direction Z1. The second connection portion 52 has, for example, a bolt hole 52X penetrating the second connection portion 52 in the thickness direction. The bolt holes 52X are provided so as to overlap with the bolt holes 41X of the terminal block 41 in a plan view seen from the Z-axis direction. Although not shown, the second connection portions 52 are fastened to the connection terminals of the external device in a state where they are overlapped in the Z-axis direction by bolts (not shown) inserted into the bolt holes 52X and the bolt holes 41X. This electrically connects the connection terminals of the external device to the bus bar 50, and also electrically connects the connection terminals of the external device to the coil 31 through the bus bar 50.

[0048] (Method of Manufacturing Reactor Device 10) Next, a method of manufacturing the reactor device 10 will be described. First, as shown in FIG. 6 , a reactor 20 is prepared, which includes a coil 31 having a winding end portion 33 and an insulating member 40. Also, a bus bar 50 having a first connection portion 51 is prepared. Next, an inclined surface 55 is formed on an end surface (first end surface) of the first connection portion 51 in the first direction X1. The inclined surface 55 is formed, for example, by cutting a corner between the end surface of the first connection portion 51 in the first direction X1 and the end surface of the first connection portion 51 in the third direction Z1. The inclined surface 55 of this embodiment is formed over the entire length of the first connection portion 51 in the Y-axis direction. In other words, the inclined surface 55 of this embodiment is also formed on a portion of the first connection portion 51 that will become the welded portion 60 (see FIG. 5 ).

[0049] Next, the bus bar 50 and the winding end portion 33 are arranged so that the end face of the first connection portion 51 in the first direction X1 faces the end face of the winding end portion 33 in the first opposite direction X2. Next, as shown in Fig. 5 , the first connection portion 51 and the winding end portion 33 are overlapped in the first direction X1. Specifically, the first connection portion 51 and the winding end portion 33 are overlapped in the first direction X1 with the end face of the first connection portion 51 in the first direction X1 and the end face of the winding end portion 33 in the first opposite direction X2 in contact with each other.

[0050] Next, the first connection portion 51 and the winding end portion 33 are joined by welding (TIG welding in this embodiment), thereby forming a welded portion 60 where the first connection portion 51 and the winding end portion 33 are integrated, and forming a structure in which an inclined surface 55 extends from the welded portion 60 in both the second direction Y1 and the second opposite direction Y2.

[0051] Next, the quality of the weld 60 is inspected. More specifically, the dimension of the weld 60 along the second direction Y1, i.e., the width of the weld 60, is measured by image inspection. The quality of the welded portion 60 is then determined based on the measured width of the weld 60. Specifically, by determining whether the measured width of the weld 60 is equal to or greater than a desired dimension, it is determined whether the joint area between the first connection portion 51 and the winding end portion 33 formed by the weld 60 is equal to or greater than a desired joint area. Therefore, in order to improve the accuracy of the quality determination of the weld 60 in the image inspection of this step, it is necessary to improve the measurement accuracy of the width of the weld 60. Here, in the image inspection of this step, an imaging device positioned closer to the third direction Z1 than the weld 60 captures images of the first connection portion 51 and the winding end portion 33, and the width of the weld 60 is measured from the captured images. In this case, in the connection structure of the first connection portion 51 and the winding end portion 33 in this embodiment, an inclined surface 55 is formed so as to extend from the welded portion 60 in both the second direction Y1 and the second opposite direction Y2. That is, the inclined surface 55 is formed in the non-welded portion adjacent to the welded portion 60. By providing this inclined surface 55, when the first connection portion 51 and the winding end portion 33 are imaged using the imaging device described above, the contrast between the welded portion 60 and the inclined surface 55 is easily obtained. Furthermore, the contrast between the inclined surface 55 and the end face of the first connection portion 51 in the third direction Z1 is easily obtained, and the contrast between the inclined surface 55 and the end face of the winding end portion 33 in the third direction Z1 is also easily obtained. For example, when light is irradiated onto the first connection portion 51 and the winding end portion 33 from the third direction Z1 side of the first connection portion 51, the light is diffusely reflected (scattered) by the inclined surface 55. This increases the contrast between the inclined surface 55 and the portions other than the inclined surface 55 (i.e., the welded portion 60, the end face of the first connection portion 51 in the third direction Z1, and the end face of the winding end portion 33 in the third direction Z1).

[0052] FIG. 7 shows an example of an image captured by the image inspection in this step. As is clear from the image in FIG. 7 , the inclined surface 55 is darker than the surrounding areas, specifically the welded portion 60, the first connection portion 51, and the winding end portion 33. The provision of such an inclined surface 55 increases the difference in shading (light and dark) between the welded portion 60 and the non-welded portion of the inclined surface 55. This improves the visibility of the boundary between the welded portion 60 and the non-welded portion of the inclined surface 55, thereby improving the visibility of the outer edge of the welded portion 60. As a result, the width dimension of the welded portion 60 along the second direction Y1, specifically the dimension indicated by the arrow in the figure, can be measured accurately. This allows for accurate determination of the quality of the welded portion 60 based on the measured width dimension of the welded portion 60. A structure determined to be non-defective by the image inspection in this step becomes the reactor device 10 shown in FIG. 1 .

[0053] (Operational Effects of the Present Embodiment) Next, operational effects of the present embodiment will be described. (1) The connection structure of the reactor device 10 includes a flat first connection portion 51 of the bus bar 50 and a flat winding end portion 33 of the coil 31. The first connection portion 51 and the winding end portion 33 are overlapped in the first direction X1. The connection structure includes a welded portion 60 at which the first connection portion 51 and the winding end portion 33 are welded together, and an inclined surface 55 provided on the first connection portion 51 and extending from the welded portion 60 in the second direction Y1. The welded portion 60 is provided on a part of the first connection portion 51 in the second direction Y1. The welded portion 60 is provided on an end of the first connection portion 51 in the third direction Z1. The inclined surface 55 is provided at a corner between a first end face of the first connection part 51 facing the winding end part 33 and a second end face of the first connection part 51 facing the third direction Z1. The inclined surface 55 is formed so as to incline toward the winding end part 33 in the third opposite direction Z2.

[0054] According to this configuration, the flat first connection portion 51 and the flat winding end portion 33 are overlapped in the first direction X1, and are joined to each other by the weld portion 60. The first connection portion 51 also has an inclined surface 55 extending from the weld portion 60 toward the second direction Y1. That is, the inclined surface 55 is formed adjacent to the weld portion 60. In other words, the inclined surface 55 is formed in a non-welded portion adjacent to the weld portion 60. This makes it easier to obtain contrast between the weld portion 60 and the inclined surface 55 when detecting the size, etc., of the weld portion 60 using an imaging device. This makes it easier to recognize the boundary between the weld portion 60 and the inclined surface 55 (non-welded portion), allowing for accurate measurement of the size of the weld portion 60, specifically, the width dimension of the weld portion 60 along the second direction Y1. This allows for accurate determination of the quality of the weld portion 60 based on the measured width dimension of the weld portion 60. More specifically, the bonded area between the first connection portion 51 and the winding end portion 33 formed by the weld 60 can be estimated with high accuracy based on the measured width of the weld 60. Therefore, by determining whether the measured width of the weld 60 is equal to or greater than a predetermined dimension, the quality of the weld 60 can be determined with high accuracy. As a result, the reliability of quality assurance for the weld 60 can be improved.

[0055] (2) The inclined surfaces 55 are formed to extend from the welded portion 60 in both the second direction Y1 and the second opposite direction Y2. That is, the inclined surfaces 55 are formed adjacent to both sides of the welded portion 60. In other words, the inclined surfaces 55 are formed on each of the non-welded portions adjacent to both sides of the welded portion 60. This makes it easier to identify the boundary between the welded portion 60 and the inclined surfaces 55 on both sides of the welded portion 60, allowing for more accurate measurement of the width dimension of the welded portion 60. Therefore, the quality of the welded portion 60 can be determined more accurately based on the measured width dimension of the welded portion 60. As a result, the reliability of quality assurance for the welded portion 60 can be further improved.

[0056] (3) The inclined surface 55 is formed only on the first connection portion 51 out of the first connection portion 51 and the winding end portion 33. This prevents the joint area between the first connection portion 51 and the winding end portion 33 from becoming smaller than when the inclined surface 55 is formed on both the first connection portion 51 and the winding end portion 33.

[0057] (4) The inclined surface 55 is formed on the first connection portion 51 that has the larger thickness between the first connection portion 51 and the winding end portion 33. This prevents the volume of the first connection portion 51 or the winding end portion 33 that has the smaller thickness from being reduced.

[0058] (5) When the first connection portion 51 and the winding end portion 33 are overlapped in the first direction X1, the inclined surface 55 forms a gap 56 between the first connection portion 51 and the winding end portion 33. If the separation distance between the first connection portion 51 and the winding end portion 33 in the first direction X1 increases, the quality of the welded portion 60 is likely to deteriorate. In response to this, the inclined surface 55 is formed so that the dimension along the third direction Z1 is larger than the dimension along the first direction X1. This prevents the separation distance between the first connection portion 51 and the winding end portion 33 in the first direction X1 from increasing. This prevents the quality of the welded portion 60 from deteriorating.

[0059] (6) The inclined surface 55 is formed to be inclined at a constant inclination angle. With this configuration, when light is irradiated onto the inclined surface 55 to detect the size of the weld 60, the light can be suitably diffusely reflected (diffusely reflected) by the inclined surface 55, which is inclined at a constant inclination angle. This increases the contrast between the weld 60 and the inclined surface 55. As a result, the boundary between the weld 60 and the inclined surface 55 is more easily recognized, allowing the width dimension of the weld 60 to be measured with greater accuracy.

[0060] (7) The welded portion 60 is a portion where the first connection portion 51 and the winding end portion 33 are TIG-welded. This configuration improves the reliability of quality assurance for the welded portion 60 welded by TIG welding.

[0061] (Modifications) The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0062] The structure of the inclined surface 55 in the above embodiment may be modified as appropriate. In the above embodiment, the inclined surface 55 is formed so that the dimension along the third direction Z1 is larger than the dimension along the first direction X1, but this is not limited to this. For example, the inclined surface 55 may be formed so that the dimension along the first direction X1 and the dimension along the third direction Z1 are the same.

[0063] The inclined surface 55 may be formed to be inclined in a curved manner, for example. The inclined surface 55 may be formed to be a curved surface that is curved in an arc or an elliptical arc, for example. In the above embodiment, the inclined surface 55 is provided only on the first connection portion 51 out of the first connection portion 51 and the winding end portion 33, but this is not limited to this. For example, the inclined surface 55 may be provided only on the winding end portion 33 out of the first connection portion 51 and the winding end portion 33. For example, the inclined surface 55 may be provided on both the first connection portion 51 and the winding end portion 33.

[0064] In the above embodiment, the thickness of the first connection portion 51 is greater than the thickness of the winding end portion 33. However, this is not limitative. For example, the thickness of the first connection portion 51 may be the same as the thickness of the winding end portion 33. For example, the thickness of the first connection portion 51 may be smaller than the thickness of the winding end portion 33.

[0065] In the above embodiment, the position where the weld 60 is formed may be changed as appropriate. For example, the weld 60 may be provided at the end of the first connection portion 51 in the second opposite direction Y2. In the manufacturing method of the above embodiment, the inclined surface 55 is formed over the entire length of the first connection portion 51 in the Y-axis direction before the first connection portion 51 and the winding end portion 33 are welded. That is, the inclined surface 55 is also formed in the portion of the first connection portion 51 that will become the weld 60, but this is not limited to this. For example, before the first connection portion 51 and the winding end portion 33 are welded, the inclined surface 55 may not be formed in the portion of the first connection portion 51 that will become the weld 60.

[0066] In the above embodiment, the first connection terminal is embodied in the first connection portion 51 of the bus bar 50, and the second connection terminal is embodied in the winding end portion 33 of the coil 31. However, this is not limiting. For example, the first connection terminal may be embodied in the first bus bar, and the second connection terminal may be embodied in the second bus bar. That is, the weld portion 60 and the inclined surface 55 may be applied to a joining structure between two bus bars, i.e., between the first bus bar and the second bus bar.

[0067] In the above embodiment, the reactor device 10 is embodied as a device having a connection structure including the welded portion 60 and the inclined surface 55. However, the present invention is not limited to this. A device having a connection structure including the welded portion 60 and the inclined surface 55 may be embodied in a device other than the reactor device 10.

[0068] The present disclosure encompasses the following aspects: Note that, for the purpose of facilitating understanding only and not for limitation, in the following description, reference signs indicating components of the embodiments are given in parentheses. (Supplementary Note 1) A flat-plate-shaped first connection terminal (51); a flat-plate-shaped second connection terminal (33) overlapping the first connection terminal in a first direction (X1); a welded portion (60) at which the first connection terminal and the second connection terminal are welded; and a pair of inclined surfaces (55) provided on the first connection terminal (51) and extending from the welded portion (60) in a second direction (Y1) intersecting the first direction and in a second opposite direction (Y2) opposite to the second direction, wherein the welded portion (60) is provided at an end of the first connection terminal (51) in a third direction (Z1) intersecting both the first direction and the second direction, and an end face of the first connection terminal (51) in the third direction (Z1) and an end face of the second connection terminal (33) in the third direction (Z1) are located on the same plane, A connection structure in which a gap (56) is formed between the first connection terminal (51) and the second connection terminal (33) by the pair of inclined surfaces (55).

[0069] In this configuration, the end faces of the first and second connection terminals in the third direction are located on the same plane, and a gap is formed between the first and second connection terminals by a pair of inclined surfaces provided on both sides of the weld, which increases the contrast between the inclined surfaces and other locations, making it possible to measure the width dimension of the weld with high accuracy.

[0070] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the meaning described above, and is intended to include all modifications within the meaning and scope of the claims.

[0071] REFERENCE SIGNS LIST 10 Reactor device 20 Reactor 30 Assembled member 31 Coil 32 Winding portion 33 Winding end (second connection terminal) 34 Winding end 35 Core 36 Inner core portion 37 Outer core portion 40 Insulating member 41 Terminal block 41X Bolt hole 42 Support portion 43 Support surface 50 Bus bar 51 First connection portion (first connection terminal) 52 Second connection portion 52X Bolt hole 53 Intermediate portion 53A Bent portion 55 Inclined surface 56 Gap 60 Welded portion X1 First direction X2 First opposite direction Y1 Second direction Y2 Second opposite direction Z1 Third direction Z2 Third opposite direction

Claims

1. A connection structure comprising: a flat first connection terminal; a flat second connection terminal overlapping the first connection terminal in a first direction; a welded portion at which the first connection terminal and the second connection terminal are welded; and an inclined surface provided on the first connection terminal and extending from the welded portion toward a second direction intersecting with the first direction, wherein the welded portion is provided on a part of the first connection terminal in the second direction, and the welded portion is provided on an end of the first connection terminal in a third direction intersecting with both the first and second directions, and the inclined surface is provided at a corner between a first end face of the first connection terminal facing the second connection terminal and a second end face of the first connection terminal facing the third direction, and the inclined surface is formed so as to incline toward a third opposite direction that is the opposite direction to the third direction as it approaches the second connection terminal.

2. A connection structure as described in claim 1, wherein the welded portion is provided at an intermediate position of the first connection terminal in the second direction, and the inclined surface extends from the welded portion in the second direction and also extends from the welded portion in a second opposite direction that is the opposite direction to the second direction.

3. The connection structure according to claim 1, wherein the inclined surface is formed only on the first connection terminal out of the first connection terminal and the second connection terminal.

4. The connection structure according to claim 3, wherein the first connection terminal has a thickness in the first direction, the second connection terminal has a thickness in the first direction, and the thickness dimension of the first connection terminal is greater than the thickness dimension of the second connection terminal.

5. A connection structure according to claim 1, wherein the first connection terminal has a thickness in the first direction, and the inclined surface is formed so that the dimension along the third direction is larger than the dimension along the first direction.

6. The connection structure according to claim 1, wherein the inclined surface is formed so as to be inclined at a constant inclination angle.

7. The connection structure according to claim 1, wherein the welded portion is a portion where the first connection terminal and the second connection terminal are TIG welded together.

8. A reactor device having a connection structure according to any one of claims 1 to 7, comprising: a reactor having a coil and a core; and a bus bar electrically connected to said coil, said bus bar having said first connection terminal; and said coil having: a winding portion formed by spirally winding a winding; and said second connection terminal being a winding end of said winding portion.

9. A method for manufacturing a semiconductor device, comprising the steps of: preparing a flat first connection terminal having a first end face; forming an inclined surface on the first end face; preparing a flat second connection terminal; overlapping the first connection terminal and the second connection terminal in the first direction with the first end face facing the second connection terminal in the first direction; joining the first connection terminal and the second connection terminal by welding to form a welded portion, and forming a structure having the inclined surface extending from the welded portion toward a second direction intersecting with the first direction; and measuring the width dimension of the welded portion along the second direction by image inspection, wherein the welded portion is formed on a part of the first connection terminal in the second direction, the welded portion is formed on an end of the first connection terminal in a third direction intersecting with both the first direction and the second direction, and the inclined surface is formed at a corner between the first end face and a second end face of the first connection terminal facing the third direction, A method for manufacturing a connection structure, wherein the inclined surface is formed so as to incline toward a third opposite direction that is opposite to the third direction as it approaches the second connection terminal.

Images