JP7783757B2 - Protective cover and reactor - Google Patents

Description

This article relates to a protective cover that houses the welding surface and a reactor equipped with this protective cover.

A reactor is known, consisting of a coil and a core. The coil generates magnetic flux when current is passed through it, and the core acts as a magnetic path for the magnetic flux generated by the coil. In other words, a reactor is an electromagnetic component that converts electrical energy into magnetic energy and stores and releases it.

This reactor is equipped with a bus bar to electrically connect the coil to the external device. The ends of the bus bar and the coil are welded by melting the ends of the bus bar or coil themselves, or by using a joining material such as solder. The bus bar and the external device are then electrically connected by fixing the terminals of the external device to the bus bar. In this way, the reactor is electrically connected to the external device via the bus bar, and current is passed through the coil.

Peripheral devices are also mounted in the vicinity of the area where the reactor is mounted. In recent years, with increasing integration, peripheral devices are sometimes placed in close proximity to the welded points at the ends of the busbar and coil. To ensure an insulating distance between these welded points and other electronic devices, it is known to use a protective cover to encase these welded points.

Japanese Patent Application Laid-Open No. 2019-021741

Conventional protective covers are inserted parallel to the welding surface, and the welding point is accommodated in the protective cover's accommodation space. The welding surface is uneven due to the presence of solidified solder and other materials. The height of these protrusions varies depending on the welding surface, making it difficult to insert the protective cover into the welding point. Furthermore, depending on the height of the protrusions, it may not be possible to insert the protective cover into the welding point. Attempting to force it may damage the internal structure of the protective cover, making it impossible to attach the protective cover to the welding point.

The present invention was made to solve the above problems, and its purpose is to provide a protective cover that is easy to install while ensuring insulation between peripheral equipment and welded points, and a reactor equipped with this protective cover.

The protective cover of the present invention is a protective cover that houses a welding surface formed by welding a first conductive member and a second conductive member, and is characterized by having a top surface, side walls extending from the edge of the top surface, an opening surface facing the top surface, a housing space defined by the top surface and the side walls and housing the welding surface, a bottom surface mounting portion on which the bottom surface of the first conductive member is placed, and a top surface abutment portion that abuts against the top surface of the first conductive member.

A reactor equipped with this protective cover is also an aspect of the present invention.

The present invention provides a protective cover that is easy to install while ensuring insulation distance between peripheral equipment and welding points, as well as a reactor equipped with this protective cover.

1 is a perspective view showing an overall configuration of a reactor according to a first embodiment; FIG. 2 is an exploded perspective view of the reactor according to the first embodiment. FIG. 10 is an enlarged view of the welded portion between the bus bar and the end of the coil. FIG. 2 is a perspective view of the protective cover of the first embodiment as seen from the bottom. FIG. 2 is a perspective view showing a state in which the protective cover of the first embodiment is attached. FIG. 10 is an enlarged cross-sectional view showing a state in which a bus bar is placed on a bottom surface placement portion. FIG. 4 is an enlarged view of a bulging portion that constitutes a clamping portion. FIG. 10 is a perspective view showing the overall configuration of a reactor according to a second embodiment. FIG. 10 is a perspective view of the protective cover of the second embodiment as seen from the bottom. FIG. 10 is a perspective view showing a state in which a protective cover according to a second embodiment is attached.

(First embodiment)
A protective cover and a reactor according to a first embodiment will be described with reference to the drawings. Fig. 1 is a perspective view showing the overall configuration of the reactor according to the first embodiment. Fig. 2 is an exploded perspective view of the reactor according to the first embodiment. In each drawing, thickness, dimensions, positional relationships, ratios, shapes, etc. may be emphasized for ease of understanding, but the present invention is not limited to such emphasis. Note that the winding axis direction of the coil is the X-axis, the horizontal arrangement direction of the coil is the Y-axis, also referred to as the arrangement direction, and the direction perpendicular to the X-axis and Y-axis is the Z-axis, also referred to as the height direction.

Reactor 10 is an electromagnetic component that converts electrical energy into magnetic energy and stores and releases it. It is used in a variety of applications, including office equipment, solar power generation systems, and automobiles. Reactor 10 includes core 1, coil 2, and resin member 3, and is housed in a case (not shown). Core 1 is made of a magnetic material and forms a magnetic path through which magnetic flux generated by coil 2 flows. Resin member 3 covers the periphery of core 1. End 21 of coil 2 is welded to bus bar 6. Bus bar 6 is electrically connected to external equipment. When power is supplied from the external equipment, current flows through coil 2 via bus bar 6, generating magnetic flux. Protective cover 9 surrounds the welded area between end 21 of coil 2 and bus bar 6, providing insulation from other components.

Core 1 can be a powder magnetic core, a ferrite magnetic core, a laminated steel plate, or a metal composite core. A metal composite core is a magnetic body made by mixing magnetic powder and resin and then hardening the resin. Core 1 forms a magnetic path through which the magnetic flux generated by coil 2 passes.

The core 1 consists of four plate-shaped portions 11 and a pair of yoke portions 12, and is not located on the inner periphery of the coil 2. The plate-shaped portions 11 are made of flat core members and are placed between adjacent coils 2, or between the coil 2 and the case, with their wide surfaces perpendicular to the arrangement direction.

The yoke portion 12 is made of a flat core member, and its wide surface is joined with an adhesive or the like to the end face of the plate-shaped portion 11, which is perpendicular to the winding axis direction of the coil 2. The yoke portion 12 has a protruding portion 13. The end face of the yoke portion 12 facing the inner peripheral surface of the coil 2 protrudes toward the inner circumference of the coil 2. Note that in this embodiment, the protruding portion 13 may or may not be inserted into the inner circumference of the coil 2. Providing the protruding portion 13 can suppress the spread of magnetic flux between the coil 2 and the yoke portion 12.

The resin member 3 covers the periphery of the core 1. Examples of resins that make up the resin member 3 include epoxy resin, unsaturated polyester resin, urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenylene Sulfide), PBT (Polybutylene Terephthalate), and composites of these. A thermally conductive filler may also be mixed into the resin.

The resin member 3 is composed of resin bodies 31 and 32 and is configured to be separable into two. The resin bodies 31 and 32 each have a plate-shaped portion covering portion 33 that covers the plate-shaped portion 11, a coil mounting portion 34 to which the coil 2 is mounted, and a yoke covering portion 35 that covers the yoke portion 12. However, the length in the winding axis direction of the plate-shaped portion covering portion 33 and coil mounting portion 34 of the resin body 31 is longer than the length in the winding axis direction of the plate-shaped portion covering portion 33 and coil mounting portion 34 of the resin body 32.

The coil 2 is composed of a single conductive member coated with insulation such as enamel. The coil 2 is formed by winding the conductive member into a cylindrical shape while shifting the winding position in the winding axis direction. In this embodiment, it is an edgewise coil made of flat copper wire. Three coils 2 are provided. The coils 2 are arranged side by side with a gap between them so that the winding axis directions are parallel. A plate-shaped portion 11 is provided between each coil 2.

End 21 of coil 2 is welded to busbar 6. Figure 3 is an enlarged view of the welded portion between the busbar and the end of the coil. As shown in Figure 3, the tip surface 211 of end 21 of coil 2 extends upward from coil 2 so as to be perpendicular to the height direction. Furthermore, at end 21 of coil 2, the wide surface of the rectangular wire is perpendicular to the winding axis direction. Note that "upward" refers to the direction away from the installation surface when reactor 10 is installed on the installation object, and "downward" refers to the direction toward the installation surface. For example, as described below, when reactor 10 is housed in a case, "upward" refers to the direction away from the bottom of the case, and "downward" refers to the direction toward the bottom of the case. This end 21 of coil 2 is the second conductive member described in the claims.

The busbar 6 is made of a flat, electrically conductive member. One end of the busbar 6 is fixed to the terminal block 7 and electrically connected to a terminal of an external device. The other end of the busbar 6 extends upward until the upper surface 61 of the busbar 6 is flush with the tip surface 211 of the coil 2, and extends parallel to the arrangement direction so as to intersect with the end surface 21 of the coil 2. That is, the upper surface 61 of the busbar 6 and the tip surface 211 of the coil 2 are flush, as shown in Figure 3. The upper surface 61 of the busbar 6 is the end surface opposite the end surface of the busbar 6 facing the resin member 3. The busbar 6 abuts against the end surface 21 of the coil 2, and the tip surface 62 of the busbar 6 protrudes in the arrangement direction beyond the end surface 21 of the coil 2. The busbar 6 is the first electrically conductive member described in the claims.

The busbar 6 and the end 21 of the coil 2 are joined by fusing the flush upper surface 61 of the busbar 6 and the tip surface 211 of the coil 2. That is, the upper surface 61 of the busbar 6 and the tip surface 211 of the coil 2 become the welding surfaces. Melted material from the busbar and coil remains on this welding surface, creating an uneven surface. Welding in this manner electrically connects the busbar 6 and the coil 2. When power is supplied from an external device, current flows through the coil 2 via the busbar 6, generating magnetic flux that flows within the core 1.

The reactor 10 has six bus bars 6, with three bus bars 6 provided at each end of the coil 2 in the winding axis direction. That is, three bus bars 6 are provided on the resin body 31 side, and the remaining three bus bars 6 are provided on the resin body 32 side. Each bus bar 6 has a welding surface welded to the coil 2, and these three welding surfaces are arranged in a straight line along the arrangement direction.

The bus bar 6 provided on the resin body 31 side is fixed to the terminal block 7. As shown in FIG. 2, the terminal block 7 is seamlessly formed integrally with the resin body 31. The terminal block 7 extends from the upper surface of the resin body 31. The bus bar 6 provided on the resin body 32 side is fixed to a terminal block (not shown) that is separate from the resin body 32.

The reactor 10 of this embodiment is housed in a case (not shown). The case is made of a lightweight metal with high thermal conductivity, such as an aluminum alloy, and has heat dissipation properties. However, the case does not necessarily have to be made of metal; it can also be made of a resin with excellent thermal conductivity, a resin with a metal heat sink embedded in part of the resin, or a resin containing a metal filler.

The case has a box-like shape that is open at the top. Specifically, the case has a roughly rectangular bottom with four sides, four side walls that rise from the edges of the four sides of the bottom, and an open top. The space enclosed by the bottom and side walls is the accommodation space that houses the reactor 10. The reactor 10 is inserted into the accommodation space of the case through the opening at the top of the case.

A filler molding portion is formed in the gap between the reactor 10 and the case. The filler molding portion is a component formed when a filler material is filled into the gap between the reactor 10 and the case and then solidified. A relatively soft, highly thermally conductive resin is suitable as the filler material to ensure the reactor 10's heat dissipation performance and reduce vibration propagation. Specific examples include silicone resin, urethane resin, epoxy resin, and acrylic resin.

The method for forming the filled molded portion may involve placing the reactor 10 in the case, then filling it with filler material and allowing it to solidify, or it may involve filling the case with filler material in advance, then placing the reactor 10 in the case, and allowing the filler material to solidify.

The reactor 10 may be provided with a sensor. The sensor detects the state of the reactor 10. The sensor is, for example, a temperature sensor. The sensor is held by a sensor holding portion of the resin member 3 between the plate-shaped portion 11 and the coil 2. The sensor transmits temperature information detected by the detection portion to the outside via lead wires.

(protective cover)
The reactor 10 includes a protective cover 9. The protective cover 9 accommodates the welding surfaces of the coil 2 and the bus bar 6 and provides insulation from components disposed close to the welding surfaces. The protective cover 9 is made of resin, and the same type of resin as that of the resin member 3 can be used. However, because the protective cover 9 is disposed in a heat-generating area, a highly heat-resistant resin such as PPS is preferable. Note that the protective cover 9 is provided only on the welding surfaces of the end 21 of the coil 2 and the bus bar 6 disposed on the resin body 32 side, but it may also be provided on the welding surfaces of the end 21 of the coil 2 and the bus bar 6 disposed on the resin body 31 side.

Figure 4 (a) is a perspective view of the protective cover as seen from the side, and (b) is a perspective view of the protective cover as seen from the bottom. Figure 5 is a perspective view showing the protective cover attached. As shown in Figure 4 (a), the protective cover 9 has an elongated shape. The protective cover 9 has a top surface 91, short side walls 92, long side walls 93, and an opening surface 94. When viewed from above, the top surface 91 has an elongated rectangular shape with a pair of opposing short sides and a pair of opposing long sides.

The center of the short side of the top surface 91 is located at a higher position (hereinafter sometimes referred to as the apex) than both ends of the short side. When the cross section of the top surface 91 is viewed from the short side, one side from the apex toward the long side wall 93 is inclined obliquely, and the other side is curved. In other words, the top surface 91 is made up of two surfaces, one of which is inclined and the other is curved. The top surface 91 is in the shape of a thin plate, and is hollow inside.

The short side walls 92 extend from the short sides of the edges of the top surface 91 toward the opening surface 94 of the protective cover 9. The long side walls 93 extend from the long sides of the edges of the top surface 91 toward the opening surface 94 of the protective cover 9. The extending tips of the short side walls 92 and long side walls 93 are at the same height. Both end portions of the short side walls 92 and long side walls 93 are fully connected to the ends of the adjacent long side walls 93 or short side walls 92. In other words, the short side walls 92 and long side walls 93 are ring-shaped.

The thickness of the short side wall 92 and the long side wall 93 is preferably 1.0 mm or more and 2.0 mm or less. If it is thinner than 1.0 mm, the strength will be insufficient and there is a risk of breakage when attaching the protective cover 9. On the other hand, if it is thicker than 2.0 mm, attachment and formability will be impaired. Note that the thickness of the short side wall 92 is the length in the direction along the long side wall 93 (the alignment direction), and the thickness of the long side wall 93 is the length in the direction along the short side wall 92 (the winding axis direction).

The end surface of the protective cover 9 facing the top surface 91 is an opening surface 94. As shown in Figure 4(b), this opening surface 94 is defined by a bottom surface mounting portion 95 (described below) provided on one of the short side walls 92, the other short side wall 92, and a pair of long side walls 93.

The welding surface, along with the end 21 of the coil 2 and a portion of the busbar 6, is inserted into the protective cover 9 through this opening 94. That is, the space defined by the top surface 91, short side walls 92, and long side walls 93 serves as a storage space for the welding surface, along with the end 21 of the coil 2 and a portion of the busbar 6. In this embodiment, the protective cover 9 stores the welding surfaces of the three busbars 6 arranged on the resin body 32 side and the coil 2. The length of the storage space in the long side direction is approximately the same as the length from the tip surface 62 of the busbar 6 arranged at one end of the three lined up busbars 6 to the tip surface 62 of the busbar 6 arranged at the other end.

As shown in Figure 5, one of the short side walls 92 has a bottom mounting portion 95. Figure 6 is an enlarged cross-sectional view showing the bus bar 6 placed on the bottom mounting portion 95. As shown in Figure 6, the bottom mounting portion 95 protrudes from the end of the short side wall 92 on the opening surface 94 side toward the storage space. The protruding length of the bottom mounting portion 95 is preferably 2.0 mm or more. By making it 2.0 mm or more, the bus bar 6 can be securely sandwiched between the bottom mounting portion 95 and the upper surface abutment portion 98 described below, and the protective cover 9 can be stably fixed and positioned.

The end surface of the bottom mounting portion 95 facing the top surface 91 is flat. This flat surface of the bottom mounting portion 95 supports the bottom surface of the bus bar 6, which protrudes beyond the end 21 of the coil 2 in the arrangement direction. The bottom surface of the bus bar 6 is the end surface of the bus bar 6 facing the resin member 3. A gap at least as long as the bus bar 6 in the height direction is provided between the bottom mounting portion 95 and the top surface 91 to support the bus bar 6. Furthermore, the height thickness of the bottom mounting portion 95 (the length from the flat surface of the bottom mounting portion 95 to the end surface opposite this flat surface) is preferably 1.0 mm or more and 2.0 mm or less. If it is thinner than 1.0 mm, it will be insufficient in strength and may be damaged when attaching the protective cover 9, for example. On the other hand, if it is thicker than 2.0 mm, it will be difficult to attach and form.

As shown in FIG. 5 , each of the pair of short side walls 92 has a tip surface abutment portion 96 that abuts against the tip surface 62 of the bus bar 6. The tip surface abutment portion 96 is the inner surface of the short side wall 92 (the end surface that defines the storage space). The tip surface abutment portion 96 is a flat surface. Each tip surface abutment portion 96 abuts against the tip surface 62 of the bus bar 6 located at both ends of the three bus bars arranged side by side.

The long side walls 93 have clamping portions 97. As shown in FIG. 4(b), the clamping portions 97 have a pair of bulging portions 971 that bulge from each long side wall 93 into the storage space. Each bulging portion 971 is arranged opposite the other and bulges toward the opposing bulging portion 971, but does not reach the other bulging portion 971. In other words, a gap is provided between the opposing bulging portions 971. The size of this gap is approximately the same as the thickness of the busbar 6. The thickness of the busbar 6 is the length from one wide surface of the flat busbar 6 to the other wide surface. The clamping portions 97 sandwich the wide surfaces of the busbar 6. The opposing bulging portions 971 have approximately the same length along the long side walls 93. Three clamping portions 97 are provided to clamp each busbar 6.

The end face of the bulge portion 971 on the opening surface 94 side is at the same height as the end face of the long side wall 93 on the opening surface 94 side, and is flush with it. Furthermore, of the end faces of the opposing bulge portion 971, the end on the opening surface 94 side is notched diagonally toward the long side wall 93. In other words, the entrance portion of the gap in the clamping portion 97 is larger than the thickness of the busbar 6, and the gap between the opposing bulge portions 971 is wide.

The bulging portion 971a constituting the clamping portion 97 may bulge so as to extend from the upper surface 91 to the opening surface 94. In this embodiment, the bulging portion 971a is provided on the short side wall 92 opposite the short side wall 92 having the bottom mounting portion 95. The bulging portion 971a is disposed opposite the bulging portion 971 with a gap therebetween, and the bus bar 6 is sandwiched between the bulging portion 971 and the bulging portion 971a. Figure 7 is an enlarged view of the bulging portion 971a. As shown in Figure 7, the tip of the bulging portion 971a has a claw portion 972 that protrudes toward the opposing bulging portion 971. This claw portion 972 abuts against the bottom surface of the bus bar 6. From the perspective of ease of insertion of the bus bar 6, the protruding length of the claw portion 972 is preferably no more than one-third of the length of the gap between the bulging portion 971 and the bulging portion 971a.

The long side wall 93 has a notch cut out at a position opposite the bulge 971a. This notch is formed by positioning a mold to sandwich the bulge 971a in order to form the claw 972. Therefore, if the claw 972 is formed without forming a notch in the long side wall 93, there is no need to form a notch. Therefore, the claw 972 may be provided not only in the bulge 971a, but also in the bulge 971 that bulges out from the long side wall 93.

An upper surface abutment portion 98 is provided on the upper surface 91 of the protective cover 9. The upper surface 91 of the upper surface abutment portion 98, which faces the upper surface 61 of the busbar 6, bulges out toward the storage space. The upper surface abutment portion 98 bulges out to a length that will abut the upper surface 61 of the busbar 6 when the busbar 6 is placed in the storage space, and its tip is flat. In other words, the tip of the upper surface abutment portion 98 abuts the upper surface 61 of the busbar 6. In other words, a space is provided between the upper surface 91 of the protective cover 9 and the upper surface of the busbar 6. This space is provided in case the welding surface provided on the upper surface 61 of the busbar 6 has irregularities and the protrusions are higher than the upper surface 61 of the busbar 6.

The upper surface abutment portion 98 may be located anywhere as long as it abuts against the upper surface 61 of the busbar 6 while avoiding the welding surface, but it is preferable to locate it in a position close to the clamping portion 97. If the distance from the clamping portion 97 is large, dimensional variation will increase, reducing the installation area between the upper surface abutment portion 98 and the upper surface 61 of the busbar 6, which may reduce the fixing and positioning function of the protective cover 9.

In this embodiment, two upper surface abutment portions 98 are provided, and they abut against the upper surfaces of the centrally located busbar 6 and the busbar 6 located on the short side wall 92 side that does not have a bottom surface mounting portion 95, respectively. However, three upper surface abutment portions 98 may also be provided, and they may abut against the busbar 6 located on the short side wall 92 side that has a bottom surface mounting portion 95.

(Attaching the protective cover)
Next, a method for attaching the protective cover 9 will be described. First, the worker holds the protective cover 9 so that the opening 94 on the short side wall 92 side having the bottom mounting portion 95 of the protective cover 9 (the opening 94 between the bottom mounting portion 95 and the clamping portion 97) faces the tip surface 62 of the bus bar 6. Then, the worker moves the protective cover 9 so that the tip surface 62 of the bus bar 6 fits into the accommodation space. At this time, the protective cover 9 is moved while the bottom mounting portion 95 and the bus bar 6 are in contact with each other or while maintaining their positions close to each other.

Then, just before the tip surface 62 of the busbar 6 abuts or abuts against the top surface 91 of the protective cover 9, the opening surface 94 of the protective cover 9 is rotated approximately 90 degrees from the bottom mounting portion 95 toward the top surface 61 (welding surface) of the busbar 6. That is, the protective cover 9 is inserted from the top surface 61 of the busbar 6. As the rotation continues, the busbar 6 is inserted into the gap of the bulge 971 that constitutes the clamping portion 97. Then, after approximately 90 degrees of rotation, the top surface abutment portion 98 abuts against the top surface 61 of the busbar 6, preventing further rotation of the protective cover 9, signaling completion of installation. When the top surface abutment portion 98 abuts against the top surface 61 of the busbar 6, the bottom mounting portion 95 is resting on the bottom surface of the busbar 6, and the tip surface abutment portion 96 abuts against the tip surface 62 of the busbar 6. In this way, by rotating the protective cover 9, the welding surface, along with the end 21 of the coil 2 and part of the bus bar 6, is accommodated in the accommodation space of the protective cover 9.

Note that a gap at least as long as the busbar 6 in the height direction is required between the bottom mounting portion 95 and the top surface 91 to allow the busbar 6 to be placed thereon, but it is preferable for this gap to be larger than the busbar's height. In other words, it is preferable for a gap to be created between the top surface 61 of the busbar 6 and the top surface 91 of the protective cover 9 when the busbar 6 is placed on the bottom mounting portion 95. As mentioned above, the protective cover 9 rotates around the bottom mounting portion 95 to accommodate the welding surface, including the end 21 of the coil 2 and part of the busbar 6, in the accommodation space. Therefore, it is easier to insert the busbar 6 between the bottom mounting portion 95 and the top surface 91 if the size of this gap is larger than the busbar's height.

(Action and effect)
As described above, the protective cover 9 of this embodiment includes the top surface 91, the short side walls 92 and long side walls 93 extending from the edge of the top surface 91, the opening 94 provided on the bottom surface, an accommodation space for accommodating the welding surface defined by the top surface 91, the short side walls 92, and the long side walls 93, a bottom surface placement portion 95 for placing the bottom surface of the bus bar 6, and an top surface abutment portion 98 that abuts against the top surface 61 of the bus bar 6. The protective cover 9 accommodates the welding surface where the end 21 of the coil 2 and the bus bar 6 are welded.

In this way, the protective cover 9 surrounds the welding surface within a storage space defined by the top surface 91, short side walls 92, and long side walls 93. This allows insulation to be achieved except on the bottom surface of the protective cover 9, making it possible to position other equipment close to the welding surface and achieving integration. The surface opposite the top surface 91 of the protective cover 9 is the opening surface 94, but since the opening surface 94 is some distance from the welding surface and other equipment is rarely placed on the opening surface 94 side, the presence of the opening surface 94 does not have a significant impact from an insulation perspective. Furthermore, the bottom surface mounting portion 95 and the top surface abutment portion 98 sandwich the bottom and top surfaces of the busbar 6, so the protective cover 9 is fixed and its vertical position is restricted.

Furthermore, the protective cover 9 can be easily attached by rotating it toward the welding surface starting from the bottom mounting portion 95. Because the welding surface has irregularities, for example, when attaching the protective cover by moving it parallel to the welding surface, if the protrusions are located higher than the upper surface 61 of the busbar 6, it may be difficult or impossible to insert. However, the protective cover 9 of this embodiment is attached by placing it over the welding surface from above, and a space is provided between the welding surface and the upper surface of the protective cover 9. This allows the protective cover 9 to be attached without being affected by the irregularities of the welding surface. Therefore, the protective cover 9 can be easily attached.

It is provided with a clamping portion 97 that protrudes from the long side wall 93 toward the bus bar 6 and clamps the bus bar 6. This allows the protective cover 9 to be positioned in the direction of the winding axis and to be more firmly fixed.

The end of the clamping portion 97 on the opening surface 94 side is cut out toward the long side wall 93. By rotating the protective cover 9, the busbar 6 and the end 21 of the coil 2 are accommodated in the accommodation space through the opening surface 94 on the bottom surface of the protective cover 9. Therefore, by cutting out the end of the clamping portion 97 on the opening surface 94 side toward the long side wall 93, it becomes easier to guide the busbar 6 into the clamping portion 97, making it easier to attach the protective cover. In particular, when accommodating multiple welding surfaces, as in this embodiment, there is a higher chance that the position of the busbar 6 will deviate from the predetermined position than when accommodating only one welding surface. However, even if there is some misalignment, by increasing the gap in the clamping portion 97, it becomes easier to insert the busbar 6 between the clamping portions 97, making it easier to attach the protective cover 9.

Furthermore, the protective cover 9 accommodates three welding surfaces, which are arranged on the same straight line. The protective cover 9 also has a pair of tip surface abutment portions 96 that abut against the tip surfaces 62 of the bus bars 6 at both ends of the three bus bars 6 arranged on the same straight line. This allows the position of the protective cover 9 to be regulated in the arrangement direction.

When viewed from the short side, the cross-sectional shape of the top surface 91 is inclined obliquely from the apex toward the long side wall 93. By inclining the top surface 91, the dimensions of the protective cover 9 can be made smaller than if the top surface 91 were curved. This allows other devices to be placed closer to the protective cover 9, enabling even greater integration. Note that in this embodiment, the curved top surface 91 may also be inclined, allowing for even greater integration.

The bulge 971a that constitutes the clamping portion 97 has a claw 972 that abuts against the underside of the bus bar 6. This securely fastens the protective cover 9 and prevents it from falling off.

Two upper surface contact portions 98 are provided, one contacting the upper surface 61 of the centrally located busbar 6 and the other contacting the upper surface 61 of the busbar 6 located on the short side wall 92 that does not have the bottom mounting portion 95. In other words, no upper surface contact portion 98 is provided that contacts the upper surface 61 of the busbar 6 located on the short side wall 92 that has the bottom mounting portion 95. As described above, the protective cover 9 is attached by rotating it around the bottom mounting portion 95. Therefore, if an upper surface contact portion 98 were provided that contacts the upper surface 61 of the busbar 6 located on the short side wall 92 that has the bottom mounting portion 95, there is a risk that the upper surface contact portion 98 and the busbar 6 would interfere with each other during attachment, making attachment difficult. Therefore, by intentionally not providing an upper surface contact portion 98 that contacts the upper surface 61 of the busbar 6 located on the short side wall 92 that has the bottom mounting portion 95, the protective cover 9 can be attached more smoothly.

Second Embodiment
A reactor 10 according to a second embodiment will be described with reference to the drawings. The same components and functions as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. Fig. 8 is a perspective view showing the overall configuration of the reactor according to the second embodiment. The second embodiment differs from the first embodiment in that a protective cover 9a is provided separately, as shown in Fig. 8.

Figure 9 is a perspective view of the protective cover of the second embodiment, viewed from the bottom. Figure 10 is a perspective view showing the protective cover of the second embodiment attached. The protective cover 9a has a curved portion 99 extending outward from the top surface 91 of the short side wall 92 that does not have the bottom mounting portion 95. "Outward" refers to the direction opposite the storage space. The curved portion 99 is made by bending a flat plate.

The busbar 6 extends upward so that the upper surface 61 of the busbar 6 is at the same height as the tip surface 211 of the end 21 of the coil 2, and curves so that the tip surface 62 of the busbar 6 intersects with the end 21 of the coil 2, extending parallel to the arrangement direction. In other words, the busbar 6 has a curved portion 63. The inner surface of the curved portion 99 is shaped to follow the curved shape of the curved portion 63 of the busbar 6 and abuts against the curved portion 63.

A claw portion 991 is provided at the tip of the curved portion 99. The length of the claw portion 991 in the direction along the short side wall 92 (in the direction of the winding axis) is shorter than the length of the curved portion 99 in the direction along the short side wall 92, and it extends from approximately the center of the tip surface of the curved portion 99. As shown in FIG. 10 , the claw portion 991 extends downward from the curved portion 99 and bends toward the short side wall 92. In other words, when the bus bar 6 is housed in the protective cover 9a, the tip of the claw portion 991 bends toward the bus bar 6. The bus bar 6 has a cutout portion into which the tip of the claw portion 991 is inserted. The tip of the claw portion 991 is inserted and fitted into this cutout portion.

In addition, the short side wall 92 that does not have the bottom mounting portion 95 has a notch 921 cut out from the bottom surface of the protective cover 9a toward the top surface 91. The width of the notch 921 is slightly larger than the thickness of the busbar 6. The height of the notch 921 is such that it abuts against the top surface 61 of the busbar 6 when the busbar 6 is housed in the protective cover 9a. In other words, the upper surface of the notch in the short side wall 92 functions as the top surface abutment portion 98.

A pair of protruding walls 922 are provided extending outward from the edge of the short-side side wall 92 that constitutes this cutout portion 921. The protruding walls 922 extend parallel to the direction along the long-side side wall 93 (the arrangement direction) so as to maintain the width of the cutout portion 921. In this embodiment, as shown in FIG. 9 , only one of the protruding walls 922 extends to the tip of the curved portion 99 and is connected to the curved portion 99, while the other protruding wall 922 does not reach the tip of the curved portion 99. However, the other protruding wall 922 may also extend to the tip of the curved portion 99 and be connected to it.

The bulging portion 971 that constitutes the clamping portion 97 is provided on this protruding wall 922. That is, the bulging portion 971 bulges from the inner wall of the protruding wall 922 toward the opposing bulging wall 971, with the gap between them being approximately the same as the width of the busbar 6. The clamping portion 97 sandwiches the wide surface of the curved busbar 6. Note that in the first embodiment, each of the pair of short side walls 92 had a tip surface abutment portion 96, but in this embodiment, only the short side wall 92 having the bottom surface mounting portion 95 has a tip surface abutment portion 96.

In this way, the protective cover 9a of the second embodiment protects each welding surface individually. The method of attaching this protective cover 9a is similar to that of the first embodiment: first, the opening surface 94 of the protective cover 9a is aligned with the tip surface 62 of the busbar 6, and the protective cover 9a is then inserted and rotated toward the top surface 61 (welding surface) of the busbar 6, starting from the bottom mounting portion 95. The clamping portions 97 then clamp the wide surface of the busbar 6, and the curved portions 99 fit over the curved portions 63 of the busbar 6. Finally, the claw portions 991 are inserted into the notches of the busbar 6 and fitted together, thereby attaching the protective cover 9a. At this time, the curved portions 99 abut against the curved portions 63 of the busbar 6, the top surface abutment portions 98 abut against the top surface 61 of the busbar 6, and the tip surface abutment portions 96 abut against the tip surface 62 of the busbar 6.

In the second embodiment, the protective cover 9a can also be easily attached by rotating it from the bottom surface mounting portion 95 toward the welding surface. The protective cover 9a has claws 991 that fit into the cutouts of the busbar 6. This allows the protective cover 9a to be more firmly fixed. The curved portion 99 conforms to the shape of the curved portion 63 of the busbar 6 and abuts against the curved portion of the busbar 6. Therefore, the busbar 6 is sandwiched between the tip surface abutment portion 96 and the curved portion 99, thereby regulating the position of the protective cover 9a in the alignment direction. In other words, while in the first embodiment the busbar 6 was sandwiched between the pair of tip surface abutment portions 96 to regulate its position, in this embodiment the protective cover 9a is positioned by sandwiching the busbar 6 between the tip surface abutment portion 96 and the curved portion 99.

Furthermore, in this embodiment, each welding surface is individually enclosed by a protective cover 9a, eliminating the need to arrange the welding surfaces in the same straight line. This allows for flexible welding positions and makes effective use of dead space.

(Other embodiments)
Although the present specification describes an embodiment of the present invention, this embodiment is presented as an example and is not intended to limit the scope of the invention. The above-described embodiment can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. The embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as set forth in the claims.

In this embodiment, the first conductive member is the bus bar 6 and the second conductive member is the end 21 of the coil 2. However, the first conductive member may be the end 21 of the coil 2 and the second conductive member may be the bus bar 6. However, as in this embodiment, it is preferable to use the bus bar 6 as the first conductive member and the second conductive member as the end 21 of the coil 2. Because the coil 2 is wound, dimensional errors are likely to occur due to design accuracy. As a result, for example, it may be difficult to insert the end 21 of the coil 2 between the clamping portion 97, or the upper surface of the end 21 of the coil 2 may not abut against the upper surface abutting portion 98. On the other hand, the bus bar 6 can be formed with better dimensional accuracy than the coil 2, and therefore can be accommodated in a predetermined location in the accommodation space of the protective covers 9, 9a, making it less likely for the protective covers 9, 9a to come off.

In this embodiment, the busbar 6 and the end 21 of the coil 2 are joined by melting the upper surface 61 of the busbar 6 and the tip surface 211 of the coil 2, but welding may also be performed using a joining material such as solder. When welding using a joining material, there is a higher possibility that the height of the welding surface will be higher than when melting. However, because the protective covers 9, 9a have a space between the welding surface and the upper surface of the protective cover 9, they can be easily attached.

In the second embodiment, the clamping portion 97 is formed by forming a bulge 971 on the protruding wall 922, but a pair of protruding walls 922 may also form the clamping portion 97. That is, the width of the cutout portion 921 may be approximately the same as the thickness of the busbar 6, and the gap between the pair of protruding walls 922 may be approximately the same as the thickness of the busbar 6, so that the protruding walls 922 can clamp the wide surface of the busbar 6. In this case, the protective cover 9a can be more firmly fixed and the protective cover 9a can be prevented from falling off. However, clamping the busbar 6 with the entire protruding wall 922 may make it difficult to insert the busbar 6, so the configuration as in the second embodiment improves the attachability of the protective cover 9.

REFERENCE SIGNS LIST 10 Reactor 1 Core 11 Plate-shaped portion 12 Yoke portion 13 Protruding portion 2 Coil 21 End portion 211 Tip surface 3 Resin member 31, 32 Resin body 33 Plate-shaped portion covering portion 34 Coil mounting portion 35 Yoke covering portion 6 Bus bar 61 Upper surface 62 Tip surface 63 Curved portion 7 Terminal block 9, 9a Protective cover 91 Upper surface 92 Short side wall 921 Cutout portion 922 Protruding wall 93 Long side wall 94 Opening 95 Bottom surface mounting portion 96 Tip surface abutting portion 97 Clamping portion 971, 971a Bulging portion 972 Claw portion 98 Top surface abutting portion 99 Curved portion 991 Claw portion

Claims (7)

A protective cover that houses a welding surface where a first conductive member and a second conductive member are welded,
The top surface and
a sidewall extending from an edge of the top surface;
an opening surface facing the upper surface;
a receiving space defined by the top surface and the side wall, the receiving space receiving the welding surface;
a bottom surface placement portion on which the bottom surface of the first conductive member is placed;
an upper surface contact portion that contacts an upper surface of the first conductive member;
To have
A protective cover characterized by: further comprising a clamping portion that protrudes from the upper surface or the side wall toward the first conductive member and clamps the first conductive member;
The protective cover according to claim 1 . an end portion of the clamping portion on the opening side is cut out toward the side wall;
The protective cover according to claim 2 . the first conductive member has a notch,
a tip surface abutting portion that abuts against a tip surface of the first conductive member;
a claw portion that fits into the notch portion;
Further comprising:
4. The protective cover according to claim 1, wherein: A plurality of the welding surfaces are accommodated;
the plurality of welding surfaces are arranged on the same straight line;
further comprising a pair of tip surface abutment portions that abut against tip surfaces of the first conductive members disposed at both ends,
4. The protective cover according to claim 1, wherein: the first conductive member is a bus bar,
the second conductive member being a coil;
6. The protective cover according to claim 1, wherein: a coil attached to the core;
a bus bar welded to an end of the coil;
A protective cover according to any one of claims 1 to 6;
To have
A reactor characterized by the above.