Electrical junction box

Abstract

One embodiment according to the present disclosure provides an electric junction box that can be reduced in weight while suppressing electromagnetic noise radiation. An electrical junction box (1) comprises: a negative-side bus bar (20) that has a cylindrical part (21) which extends along a first axis (X), and a negative-side connection tab (22) and a bus bar-side male tab (23) which protrude along the first axis (X) from a part of the cylindrical part (21) in the circumferential direction; a plurality of fuses (41) that are accommodated inside the cylindrical part (21); a positive-side connection tab (32) and a male tab (43) that are electrically connected to the plurality of fuses (41) and that protrude to the outside of the cylindrical part (21) along the first axis (X); a resin housing (10) that accommodates the negative-side bus bar (20); and a first magnetic body (101) and a second magnetic body (102) that are provided to the portions of the housing (10) corresponding to the peripheries of the positive-side connection tab (32) and the male tab (43) which protrude to the outside of the cylindrical part (21).

Description

Electrical junction box

[0001] The present disclosure relates to an electrical junction box.

[0002] Conventionally, an electrical junction box to which a high-voltage electric wire is connected includes a negative bus bar having a cylindrical portion, a plurality of fuses housed in the cylindrical portion, and a metal housing that houses the negative bus bar (see, for example, Patent Document 1). The negative bus bar has a bus bar tab that protrudes from a portion of the cylindrical portion in the circumferential direction. Furthermore, a fuse tab electrically connected to the fuse protrudes outside the cylindrical portion to form a pair with the bus bar tab. The paired fuse tab and bus bar tab are electrically connected to, for example, an external power source or an external power consuming device. In such an electrical junction box, the fuse and fuse tab, through which a large current flows, are covered by the metal housing, thereby suppressing electromagnetic noise radiation from the electrical junction box.

[0003] JP 2023-65141 A

[0004] In the electrical junction box described above, the entire housing is made of metal, which can suppress electromagnetic noise radiation, but the overall weight of the electrical junction box is heavy. An object of the present disclosure is to provide an electrical junction box that can be made lighter while suppressing electromagnetic noise radiation.

[0005] The electrical connection box of the present disclosure comprises a negative side bus bar having a cylindrical portion extending along a first axis and a bus bar tab protruding along the first axis from a circumferential portion of the cylindrical portion; a plurality of fuses housed inside the cylindrical portion; a fuse tab electrically connected to the plurality of fuses and protruding outside the cylindrical portion along the first axis; a resin housing that houses the negative side bus bar; and a magnetic body provided in the housing at a position corresponding to the periphery of the fuse tab protruding outside the cylindrical portion.

[0006] According to the electrical junction box of the present disclosure, it is possible to reduce the weight while suppressing the radiation of electromagnetic noise.

[0007] FIG. 1 is a partial cross-sectional view of an electrical junction box according to an embodiment. FIG. 2 is a perspective view of an electrical junction box according to an embodiment. FIG. 3 is a perspective view of an electrical junction box according to an embodiment. FIG. 4 is a perspective view showing the internal configuration of an electrical junction box according to an embodiment. FIG. 5 is a perspective view showing the internal configuration of an electrical junction box according to an embodiment. FIG. 6 is a partial cross-sectional view of a negative bus bar and a composite fuse according to an embodiment. FIG. 7 is a block diagram showing connections in an electrical junction box according to an embodiment. FIG. 8 is a perspective view of a composite fuse according to an embodiment. FIG. 9 is a side view of a composite fuse according to an embodiment, viewed from the fixing tab side. FIG. 10 is an explanatory diagram of the fixing tab of a composite fuse according to an embodiment, viewed from the fuse main body side. FIG. 11 is a perspective view of a fuse according to an embodiment. FIG. 12 is a side view of a fixing tab of a fuse according to an embodiment. FIG. 13 is a side view of a fuse according to an embodiment, viewed from the fixing tab side. FIG. 14 is an explanatory diagram of the fixing tab of a fuse according to an embodiment, viewed from the fuse main body side. FIG. 15 is a partial cross-sectional view of an electrical junction box according to another example.

[0008] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be described. The electrical junction box of the present disclosure includes: [1] a negative-side bus bar having a cylindrical portion extending along a first axis and a bus bar tab protruding along the first axis from a circumferential portion of the cylindrical portion, a plurality of fuses housed inside the cylindrical portion, a fuse tab electrically connected to the plurality of fuses and protruding outside the cylindrical portion along the first axis, a resin housing that houses the negative-side bus bar, and a magnetic body provided in the housing at a portion corresponding to the periphery of the fuse tab protruding outside the cylindrical portion.

[0009] According to this configuration, the fuse is housed in the cylindrical portion of the negative bus bar, which suppresses electromagnetic noise radiation from the covered fuse. Furthermore, a magnetic material is provided in the housing at a location corresponding to the periphery of the fuse tab that protrudes outside the cylindrical portion of the negative bus bar, thereby suppressing electromagnetic noise radiation from the fuse tab. Furthermore, because the housing that houses the negative bus bar is made of resin, the electrical connection box can be made lighter than if it were made of metal.

[0010] [2] In the above [1], the magnetic body may be provided on the entire periphery of the housing. According to this configuration, since the magnetic body is provided on the entire periphery of the housing, radiation of electromagnetic noise from the fuse tab is effectively suppressed.

[0011] [3] In the above [1] or [2], the magnetic body may be provided in a range including the entire fuse tab protruding from the cylindrical portion in the housing along the first axis.

[0012] According to this configuration, the magnetic body is arranged in a range that includes the entire area along the first axis of the fuse tab protruding from the cylindrical portion in the housing, thereby effectively suppressing radiation of electromagnetic noise from the fuse tab.

[0013] [4] In any one of [1] to [3] above, the housing may have a holding claw for holding the magnetic body. According to this configuration, since the housing has the holding claw for holding the magnetic body, the magnetic body can be easily attached to the housing by assembly. That is, compared to, for example, a case where the magnetic body is fixed to the housing using a separate member such as adhesive tape, the magnetic body can be easily fixed without using a separate part.

[0014] [5] In any one of [1] to [4] above, the fuse tab may include a first fuse tab protruding outward from a first end of the cylindrical portion and a second fuse tab protruding outward from a second end of the cylindrical portion, and the magnetic body may include a first magnetic body provided in a portion of the housing corresponding to the periphery of the first fuse tab and a second magnetic body provided in a portion of the housing corresponding to the periphery of the second fuse tab.

[0015] According to this configuration, the fuse tabs include a first fuse tab protruding outward from the first end of the cylindrical portion and a second fuse tab protruding outward from the second end of the cylindrical portion, so that, for example, external terminals can be connected at both ends of the electrical junction box. In this way, the fuse tabs are not crowded together compared to when the fuse tabs protrude only from the first end of the cylindrical portion, so that a larger space can be used to connect external terminals. Furthermore, the magnetic body includes a first magnetic body provided in a portion of the housing corresponding to the periphery of the first fuse tab and a second magnetic body provided in a portion of the housing corresponding to the periphery of the second fuse tab, so that radiation of electromagnetic noise from the first fuse tab and the second fuse tab is suppressed.

[0016] [6] In any one of [1] to [4] above, the fuse tab may protrude only from the first end of the cylindrical portion. According to this configuration, since the fuse tab protrudes only from the first end of the cylindrical portion, all external terminals can be connected to one end of the electrical junction box. Furthermore, since the magnetic body only needs to be provided at one end of the housing, the number of magnetic bodies can be reduced compared to a configuration in which magnetic bodies are provided at both ends of the housing.

[0017] [Details of the Embodiments of the Present Disclosure] Specific examples of the present disclosure will be described below with reference to the drawings. In each drawing, for the convenience of explanation, some of the configurations may be exaggerated or simplified. Furthermore, the dimensional proportions of each part may differ from one drawing to another. Furthermore, 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 equivalent to the claims.

[0018] Specific examples of the electrical junction box of the present disclosure will be described below with reference to the drawings. In each drawing, for the sake of convenience, some components may be exaggerated or simplified. Furthermore, the dimensional proportions of each part may differ from one drawing to another.

[0019] As used herein, the term "cylindrical" does not only refer to a cylindrical object having a continuous peripheral wall formed around the entire circumference, but also includes a cylindrical object formed by combining multiple components or a C-shape having a notch or other notch along the circumference. The outer peripheral shape of a "cylindrical" object includes, but is not limited to, a circle, an ellipse, and a polygon with sharp or rounded corners. A "cylindrical" object has a through hole in a plan view, and includes objects in which the outer peripheral shape and the inner peripheral shape of the through hole are the same or different. A "cylindrical" object includes objects having a predetermined length extending along the axial direction of the central axis passing through the center of the through hole, regardless of the length. In this specification, "facing" refers to surfaces or components facing each other, and includes not only cases where the surfaces are completely facing each other, but also cases where the surfaces are partially facing each other. Furthermore, "facing" in this specification includes both cases where a separate component is interposed between two parts and cases where there is no interposition between the two parts. Furthermore, terms such as "first," "second," and "third" in this specification are used merely to distinguish between objects and not to rank the objects. 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 equivalent to the claims.

[0020] 1, the electrical junction box 1 of this embodiment has a housing 10. The housing 10 has a cylindrical housing main body 11 extending along a first axis X, a first end plate 12 fixed to a first end 11a of the housing main body 11, and a second end plate 13 fixed to a second end 11b of the housing main body 11. In the housing 10, specifically, the housing main body 11, the first end plate 12, and the second end plate 13 are made of resin.

[0021] Each drawing shows a first axis X, a second axis Y, and a third axis Z, which are perpendicular to each other. Each drawing also shows a first direction X1, which is one direction along the first axis X, and a first opposite direction X2, which is the opposite direction to the first direction X1.

[0022] 1 to 3 , the housing body 11 is formed in a cylindrical shape. The housing body 11 has a first holding claw 14 and a second holding claw 15 as holding claws. The first holding claw 14 and the second holding claw 15 are integrally molded with the housing body 11.

[0023] 1 and 2 , the first holding claws 14 are provided on the first end 11a side of the housing body 11. Two first holding claws 14 are provided at equal intervals around the circumference of the housing body 11. Each first holding claw 14 has a first protruding portion 14a protruding radially outward from the outer circumferential surface of the housing body 11, a first extending portion 14b extending in the first direction X1 from the tip of the first protruding portion 14a, and a first claw portion 14c protruding radially inward of the housing body 11 from the tip of the first extending portion 14b.

[0024] 1 and 3 , the second holding claws 15 are provided on the second end 11b side of the housing body 11. Two second holding claws 15 are provided at equal intervals around the circumference of the housing body 11. The second holding claws 15 have a second protruding portion 15a protruding radially outward from the outer circumferential surface of the housing body 11, a second extending portion 15b extending from the tip of the second protruding portion 15a in the first opposite direction X2, and a second claw portion 15c protruding radially inward of the housing body 11 from the tip of the second extending portion 15b.

[0025] As shown in FIG. 1 , the first end plate 12 is formed in a disk shape and fixed to the first end 11a of the housing body 11. The first end plate 12 has a first connection tubular portion 12a that extends tubularly inside the housing body 11 in the first opposite direction X2 while communicating between the inside and outside of the housing body 11. The electrical junction box 1 has a first external terminal 16 provided within the first connection tubular portion 12a. The first external terminal 16 includes a positive side connection tab 32 and a negative side connection tab 22. In this embodiment, the positive side connection tab 32 constitutes a fuse tab and a first fuse tab. The negative side connection tab 22 constitutes a bus bar tab.

[0026] As shown in FIG. 1 , the second end plate 13 is formed in a disk shape and fixed to the second end 11b of the housing body 11. The second end plate 13 has a second connection tubular portion 13a that extends tubularly inside the housing body 11 in the first direction X1 while communicating with the inside and outside of the housing body 11. The electrical junction box 1 has second external terminals 17 provided within the second connection tubular portion 13a. The second external terminals 17 include multiple pairs of male tabs 43 and bus bar side male tabs 23. In this embodiment, the second external terminals 17 include three pairs of male tabs 43 and bus bar side male tabs 23. In this embodiment, the male tabs 43 constitute fuse tabs and second fuse tabs. The bus bar side male tabs 23 constitute bus bar tabs.

[0027] The first connecting tube portion 12a shown in Fig. 3 is for inserting a connector 81 shown in Fig. 7. As shown in Fig. 7, the connector 81 is provided on a wire harness 80 that connects the electrical junction box 1 and a device 71. The wire harness 80 includes a connector 81 having an external terminal (not shown), a connector 82 that is connected to the device 71, and a positive electric wire 83a and a negative electric wire 83b between the connector 81 and the connector 82.

[0028] The device 71 is an electrical device provided in a vehicle, such as an external power source such as a battery pack or a charge / discharge controller connected to the battery pack. The device 71 has a positive terminal and a negative terminal, which are connected to a positive electric wire 83a and a negative electric wire 83b, respectively. The electrical junction box 1 is connected to the device 71 by a wire harness 80. The positive connection tab 32 of the first external terminal 16 of the electrical junction box 1 is connected to the positive terminal of the device 71 by the positive electric wire 83a of the wire harness 80. The negative connection tab 22 of the first external terminal 16 of the electrical junction box 1 is connected to the negative terminal of the device 71 by the negative electric wire 83b of the wire harness 80.

[0029] The second connection tube portion 13a shown in Fig. 2 is for inserting a connector 91 shown in Fig. 7. As shown in Fig. 7, the connector 91 is provided on a wire harness 90 that connects the electrical junction box 1 and a plurality of devices 72. The wire harness 90 includes a connector 91 having an external terminal (not shown), a connector 92 that is connected to the device 72, and a positive electric wire 93a and a negative electric wire 93b between the connector 91 and the connector 92.

[0030] The devices 72 are electrical devices provided in the vehicle, such as external power consuming devices such as a motor, a unit for driving the motor, a voltage converter, and a low-voltage battery unit. Each of the devices 72 has a positive terminal and a negative terminal. The devices 72 and the electrical junction box 1 are electrically connected by a wire harness 90. The positive terminal of the device 72 is connected to the male tab 43 constituting the second external terminal 17 of the electrical junction box 1 by a positive electric wire 93a of the wire harness 90. The negative terminal of the device 72 is connected to the bus bar male tab 23 constituting the second external terminal 17 of the electrical junction box 1 by a negative electric wire 93b of the wire harness 90.

[0031] 4, the electrical junction box 1 includes a negative bus bar 20, a positive bus bar 30, and a composite fuse 40, which are housed in a housing 10. (Configuration of the composite fuse 40) The composite fuse 40 of this embodiment is made up of three fuses 41. The three fuses 41 have the same shape.

[0032] 6, the fuse 41 includes a fuse body 42, a male tab 43, and a fixing tab 44. The fuse body 42 is formed in a cylindrical shape and has a first end surface 42a and a second end surface 42b. The fuse body 42 is configured to melt when a current greater than a specified value flows between the male tab 43 and the fixing tab 44.

[0033] The fixing tabs 44 are provided on the first end surface 42a of the fuse body 42. The male tabs 43 are provided on the second end surface 42b of the fuse body 42. In this embodiment, the fixing tabs 44 are formed to protrude from the first end surface 42a of the fuse body 42. In this embodiment, the male tabs 43 are formed to protrude from the second end surface 42b of the fuse body 42. In this embodiment, the fixing tabs 44 of the three fuses 41 are connected to each other by bolts 61 and nuts 62.

[0034] The three fuses 41 are connected to one another by one bolt 61 and nut 62. The fuses 41 are arranged at equal angular intervals along the circumferential direction of a circle centered on the axis of the bolt 61. In other words, the three fuses 41 are arranged at the vertices of an equilateral triangle centered on the axis of the bolt 61 (see FIGS. 8 and 9).

[0035] (Configuration of Positive Bus Bar 30) As shown in Fig. 6, the positive bus bar 30 has a fixing portion 31 and a positive connection tab 32. The fixing portion 31 and the positive connection tab 32 extend in directions perpendicular to each other. As a result, the fixing portion 31 and the positive connection tab 32 form the positive bus bar 30 in an L-shape. The fixing portion 31 is electrically connected to the fixing tab 44 of each fuse 41 that constitutes the composite fuse 40.

[0036] In this embodiment, the positive bus bar 30 is connected to the fixing tabs 44 of each fuse 41 by bolts 61 and nuts 62. A through hole 31a is formed in the fixing portion 31 of the positive bus bar 30. The bolt 61 that fixes the fuse 41 is inserted into the through hole 31a. That is, in this embodiment, the fixing tabs 44 of the fuses 41 and the positive bus bar 30 are connected to each other by the bolt 61 and the nut 62. As a result, the fixing tabs 44 of each fuse 41 and the positive bus bar 30 have the same potential. Furthermore, the male tabs 43 of each fuse 41 have the same potential as the positive bus bar 30.

[0037] (Configuration of negative bus bar 20) The negative bus bar 20 is made of metal. For example, the negative bus bar 20 is formed into a cylindrical shape by rolling a metal plate. The negative bus bar 20 serves as a noise shield, i.e., a measure against electromagnetic noise for the fuse 41 that it surrounds.

[0038] 4 and 5 , the negative bus bar 20 has a cylindrical portion 21 extending along the first axis X, and one negative connection tab 22 and three bus bar male tabs 23 protruding along the first axis X from a portion of the circumference of the cylindrical portion 21. The negative bus bar 20 is housed in the housing 10.

[0039] The cylindrical portion 21 accommodates the composite fuse 40, i.e., three fuses 41. The cylindrical portion 21 has a first end 21a on the first direction X1 side and a second end 21b on the first opposite direction X2 side.

[0040] The negative side connection tab 22 is formed to protrude from the first end 21a of the cylindrical portion 21. The three bus bar side male tabs 23 are formed to protrude from the second end 21b of the cylindrical portion 21. The negative side connection tab 22 is arranged opposite the positive side connection tab 32. The three bus bar side male tabs 23 are arranged at equal angular intervals along the circumferential surface of the cylindrical portion 21. The bus bar side male tabs 23 are arranged opposite the male tabs 43 of the fuse 41.

[0041] The positive connection tab 32 and the negative connection tab 22 form a pair and function as a first external terminal 16 (see FIGS. 3 and 5) connected to a positive electric wire 83 a and a negative electric wire 83 b shown in Fig. 7. The male tab 43 and the bus bar side male tab 23 form a pair and function as a second external terminal 17 (see FIGS. 2 and 4) connected to a positive electric wire 93 a and a negative electric wire 93 b shown in Fig. 7.

[0042] (Details of the Composite Fuse 40 and the Fuse 41) Next, the composite fuse 40 and each fuse 41 according to one embodiment will be described with reference to FIGS.

[0043] 8 to 10, the composite fuse 40 is made up of three fuses 41. Each fuse 41 has a fuse body 42, a male tab 43, and a fixing tab 44.

[0044] 11 to 13, the fixing tab 44 has a first connecting portion 51, a second connecting portion 52, and a fixing portion 53. The first connecting portion 51 extends from the first end surface 42a of the fuse body 42 along the first axis X. The first connecting portion 51 has a tip 51a on the opposite side to the fuse body 42. The second connecting portion 52 extends from the tip 51a of the first connecting portion 51 in a direction perpendicular to the first axis X. The second connecting portion 52 has a tip 52a on the opposite side to the first connecting portion 51.

[0045] The fixed portion 53 is connected to a tip 52a of the second connecting portion 52. The fixed portion 53 has a fixed hole 53a penetrating the fixed portion 53 on a fixed shaft 53AX extending along the first axis X. The fixed hole 53a is formed so that a bolt 61 shown in FIG. 6 can be inserted therethrough. In other words, the fixed hole 53a serves as an insertion hole through which the bolt 61 is inserted.

[0046] As shown in FIGS. 11 to 13 , the fixed portion 53 has a plurality of fixed pieces 54. As shown in FIGS. 11 and 13 , the fixed pieces 54 are arranged in the circumferential direction around the fixed shaft 53AX. Each fixed piece 54 is formed in an arc shape centered on the fixed shaft 53AX. In this embodiment, the fixed portion 53 has three fixed pieces 54. The fixed pieces 54 are arranged so that they partially overlap each other when viewed from the direction in which the fixed shaft 53AX extends. The fixed pieces 54 are integrally connected to each other at the overlapping portions. As shown in FIG. 12 , the fixed portion 53 has three fixed pieces 54 arranged so that they are offset in the direction along the fixed shaft 53AX. As a result, the fixed portion 53 has a step 54a in the circumferential direction. The fixed portion 53 is formed in an arc shape having a first arc end 53b and a second arc end 53c that are spaced a predetermined distance apart in the circumferential direction.

[0047] In this embodiment, as shown in FIG. 13 , the fixed pieces 54 are disposed at equal angular intervals and offset in the circumferential direction of a circle centered on the fixed shaft 53AX. Each fixed piece 54 is formed to have an angle of 120 degrees around the fixed shaft 53AX. In other words, each fixed piece 54 is formed in an arc shape with a central angle of 120 degrees. The fixed portion 53 has an opening 55 formed between the first arc end 53b and the second arc end 53c. When viewed from the direction in which the fixed shaft 53AX extends, the opening 55 has a shape corresponding to the overlapping portions 56 of two circumferentially adjacent fixed pieces 54, and in this embodiment, the opening 55 is formed to have a size corresponding to the two overlapping portions 56.

[0048] Fuses 41 each having a fixing tab 44 with fixing portions 53 of this shape are assembled together so that the fixing portions 53 are overlapped and shifted from one another in the circumferential direction, as shown in FIGS.

[0049] The fixing pieces 54 of the three fuses 41 forming a ring are stacked along the first axis X along which the fixing shaft 53AX extends. As shown in FIG. 6 , the fixing tabs 44 of the three fuses 41 and the fixing portion 31 of the positive bus bar 30 are fastened together with bolts 61 and nuts 62.

[0050] 1 to 3, the electrical connection box 1 includes a first magnetic body 101 and a second magnetic body 102. The first magnetic body 101 and the second magnetic body 102 are made of, for example, ferrite.

[0051] 1 and 3 , the first magnetic body 101 is formed in a cylindrical shape. The first magnetic body 101 is held by the first holding claws 14. More specifically, the first magnetic body 101 is moved relative to the housing 10 in the first opposite direction X2, so that the first magnetic body 101 is fitted onto the housing main body 11 and held by the first holding claws 14. The first magnetic body 101 assembled to the housing 10 in this manner is provided around the entire periphery of the housing 10.

[0052] 1 , the first magnetic body 101 is provided in a portion of the housing 10 corresponding to the periphery of the positive connection tab 32 serving as a first fuse tab that protrudes outward from the first end 21 a of the cylindrical portion 21 of the negative bus bar 20. The first magnetic body 101 has a portion that overlaps with the positive connection tab 32 in the radial direction of the housing main body 11. The first magnetic body 101 of this embodiment is provided in a range that includes the entire positive connection tab 32 protruding from the cylindrical portion 21 along the first axis X in the housing 10. The first magnetic body 101 serves as a countermeasure against electromagnetic noise, i.e., a noise shield, for the positive connection tab 32 that it surrounds.

[0053] 1 and 2 , the second magnetic body 102 is formed in a cylindrical shape. The second magnetic body 102 is held by the second holding claws 15. More specifically, the second magnetic body 102 is moved relative to the housing 10 in the first direction X1, so that the second magnetic body 102 is fitted onto the housing main body 11 and held by the second holding claws 15. The second magnetic body 102 assembled to the housing 10 in this manner is provided around the entire periphery of the housing 10.

[0054] 1 , the second magnetic body 102 is provided in a portion of the housing 10 corresponding to the periphery of a male tab 43 serving as a second fuse tab that protrudes outward from the second end 21 b of the cylindrical portion 21 of the negative bus bar 20. The second magnetic body 102 has a portion that overlaps with the male tab 43 in the radial direction of the housing main body 11. The second magnetic body 102 of this embodiment is provided in a range that includes the entire male tab 43 protruding from the cylindrical portion 21 in the housing 10 along the first axis X. The second magnetic body 102 serves as a countermeasure against electromagnetic noise, i.e., a noise shield, for the male tab 43 that it surrounds.

[0055] (Operation of the Present Embodiment) Next, the operation of the electrical junction box 1 configured as described above will be described. For example, a large current flows through the fuse 41 in the electrical junction box 1 from the device 71, which is an external power source, to the device 72, which is an external power consumption device. Specifically, the large current flows from the positive connection tab 32 through the fuse body 42 to the male tab 43, causing electromagnetic noise to be emitted from the positive connection tab 32, the fuse body 42, and the male tab 43. However, because the fuse body 42 is covered by the cylindrical portion 21 of the negative bus bar 20 and the positive connection tab 32 and the male tab 43 are covered by the first magnetic body 101 and the second magnetic body 102, the radiation of electromagnetic noise from the electrical junction box 1 to the outside is suppressed.

[0056] (Advantages of the Present Embodiment) Next, advantages of the above-described embodiment are described below. (1) Because the fuse 41 is housed in the cylindrical portion 21 of the negative bus bar 20, the cylindrical portion 21 suppresses electromagnetic noise radiation from the fuse 41, which is covered by the cylindrical portion 21. Furthermore, the first magnetic body 101 and the second magnetic body 102 are provided in the housing 10 at locations corresponding to the peripheries of the positive connection tab 32 and the male tab 43 that protrude outside the cylindrical portion 21 of the negative bus bar 20. Therefore, electromagnetic noise radiation from the positive connection tab 32 and the male tab 43 is suppressed. Furthermore, because the housing 10 that houses the negative bus bar 20 is made of resin, the electrical junction box 1 can be made lighter than if it were made of metal. Furthermore, for example, if the housing 10 were made of metal, molding the housing 10 to a complex shape would be difficult and expensive. However, because the housing 10 is made of resin, molding is easier, thereby enabling, for example, cost reduction.

[0057] (2) Since the first magnetic body 101 and the second magnetic body 102 are provided around the entire periphery of the housing 10, radiation of electromagnetic noise from the positive side connection tab 32 and the male tab 43 is effectively suppressed.

[0058] (3) The first magnetic body 101 is provided in a range that includes the entire area along the first axis X of the positive connection tab 32 that protrudes from the cylindrical portion 21 in the housing 10, thereby effectively suppressing radiation of electromagnetic noise from the positive connection tab 32. Furthermore, the second magnetic body 102 is provided in a range that includes the entire area along the first axis X of the male tab 43 that protrudes from the cylindrical portion 21 in the housing 10, thereby effectively suppressing radiation of electromagnetic noise from the male tab 43.

[0059] (4) Because the housing 10 has the first retaining claws 14 and the second retaining claws 15 that retain the first magnetic body 101 and the second magnetic body 102, the first magnetic body 101 and the second magnetic body 102 can be easily provided to the housing 10 by assembling them. That is, compared to, for example, a case where the first magnetic body 101 and the second magnetic body 102 are fixed to the housing 10 using a separate member such as adhesive tape, they can be easily fixed without using a separate part.

[0060] (5) The fuse tabs include a positive connection tab 32 as a first fuse tab protruding from the first end 21a of the tubular portion 21 to the outside, and a male tab 43 as a second fuse tab protruding from the second end 21b of the tubular portion 21 to the outside. Therefore, for example, external terminals can be connected at both ends of the electrical junction box 1. This configuration allows the fuse tabs to be less densely packed than when the positive connection tab 32 and the male tab 43 protrude only from the first end 21a of the tubular portion 21, thereby increasing the space available for connecting external terminals. Furthermore, the magnetic body includes a first magnetic body 101 provided in a portion of the housing 10 corresponding to the periphery of the positive connection tab 32 and a second magnetic body 102 provided in a portion of the housing 10 corresponding to the periphery of the male tab 43. Therefore, electromagnetic noise radiation from the positive connection tab 32 and the male tab 43 is suppressed.

[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] In the above embodiment, the fuse tab includes the positive connection tab 32 protruding outward from the first end 21 a of the tubular portion 21 and the male tab 43 protruding outward from the second end 21 b of the tubular portion 21. However, the present invention is not limited to this. For example, the fuse tab may be configured to protrude only from the first end 21 a of the tubular portion 21.

[0063] Specifically, for example, the electrical junction box 1 may be modified as shown in Fig. 15. The first end plate 12 in this example has a first connecting tubular portion 12a and a second connecting tubular portion 12b. The second end plate 13 in this example does not have the second connecting tubular portion 13a (see Fig. 1) of the above embodiment.

[0064] The fuse tab in the electrical junction box 1 of this example includes a positive connection tab 32 similar to that of the above embodiment that protrudes outward from the first end 21 a of the cylindrical portion 21, and a plurality of male tabs 111 that protrude outward from the first end 21 a of the cylindrical portion 21. That is, the male tabs 111 of this example (see FIG. 15 ) are formed by folding back the male tabs 43 (see FIG. 4 ) of the above embodiment so that they protrude outward from the first end 21 a of the cylindrical portion 21.

[0065] Furthermore, unlike the bus bar side male tab 23 (see FIG. 4) of the above embodiment, the bus bar side male tab 112 of this example is formed to protrude from the first end 21a of the tubular portion 21, similar to the negative side connection tab 22. Furthermore, the male tab 111 and the bus bar side male tab 112 are provided inside the second connection tubular portion 12b.

[0066] In this way, the positive connection tab 32, which is a fuse tab, and the plurality of male tabs 111 protrude only from the first end 21a of the cylindrical portion 21, so that, for example, all external terminals can be connected to one end of the electrical junction box 1. Furthermore, since it is only necessary to provide the magnetic body at one end of the housing 10, i.e., it is possible to use only the first magnetic body 101, the number of magnetic bodies can be reduced compared to, for example, a configuration in which magnetic bodies are provided at both ends of the housing 10.

[0067] In the above embodiment, the first magnetic body 101 and the second magnetic body 102 are provided around the entire circumference of the housing 10, but this is not limiting and the first magnetic body 101 and the second magnetic body 102 may not be provided around the entire circumference of the housing 10. For example, the first magnetic body 101 and the second magnetic body 102 may have a C-shaped notch in a portion of the circumference. Furthermore, for example, the first magnetic body 101 and the second magnetic body 102 may be configured to be made up of a plurality of magnetic bodies arranged around the circumference of the housing 10 with gaps between them.

[0068] In the above embodiment, the first magnetic body 101 is provided in a range that includes the entire area along the first axis X of the positive connection tab 32 that protrudes from the cylindrical portion 21 in the housing 10, but this is not limited to this. For example, the first magnetic body 101 may be provided in a range that is smaller than the entire area along the first axis X of the positive connection tab 32.

[0069] Although the second magnetic body 102 is described as being provided in a range including the entire area along the first axis X of the male tab 43 protruding from the cylindrical portion 21 in the housing 10, this is not limitative. For example, the second magnetic body 102 may be provided in a range smaller than the entire area along the first axis X of the male tab 43.

[0070] In the above embodiment, the housing 10 has the first holding claws 14 and the second holding claws 15 that hold the first magnetic body 101 and the second magnetic body 102, but this is not limited to this. For example, the first magnetic body 101 and the second magnetic body 102 may be fixed to the housing 10 using separate members such as adhesive tape. Furthermore, the shapes of the first holding claws 14 and the second holding claws 15 may be changed to other shapes as long as the first magnetic body 101 and the second magnetic body 102 can be assembled and the first magnetic body 101 and the second magnetic body 102 can be held.

[0071] In the above embodiment, the electrical junction box 1 is configured to include the positive connection tab 32 and the male tab 43 as fuse tabs that are electrically connected to the fuse 41 and that protrude along the first axis X to the outside of the cylindrical portion 21, but this is not limiting. For example, the positive connection tab 32 may be a fuse tab that protrudes directly from the fuse body 42 of the fuse 41, similar to the male tab 43. Furthermore, for example, the male tab 43 may be a fuse tab that is a separate member from the male tab 43, that is electrically connected to the male tab 43 that protrudes from the fuse body 42, and that protrudes to the outside of the cylindrical portion 21.

[0072] In the above embodiment, the number of fuses 41 may be changed as appropriate. For example, the electrical junction box 1 of the above embodiment may be configured to include two or four or more fuses 41.

[0073] In the above embodiment, the tubular portion 21 of the negative bus bar 20 is cylindrical, but this is not limited thereto and may be another shape, for example, a rectangular tubular shape. The shape of the negative bus bar 20 may also be changed depending on the shape of the composite fuses 40 surrounded by the negative bus bar 20, the number of fuses 41, etc.

[0074] In the above embodiment, the housing body 11 of the housing 10 of the electrical junction box 1 is cylindrical, but this is not limiting and the housing body 11 may have another shape, for example, a rectangular tubular shape. The shape of the housing 10 may also be changed depending on the shape of the negative bus bar 20 housed in the housing body 11.

[0075] In the above embodiment, the housing 10 is configured to have a housing main body 11, a first end plate 12, and a second end plate 13, but it may be changed to another configuration as long as it can accommodate the negative side bus bar 20.

[0076] In the above embodiment, the first magnetic body 101 and the second magnetic body 102 are made of, for example, ferrite. However, they may be made of other magnetic materials as long as they can suppress the radiation of electromagnetic noise.

[0077] 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 numerals representing components of the embodiments are shown in parentheses. (Supplementary Note 1) An electrical connection box (1) comprising: a negative-side busbar (20) including a cylindrical portion (21) extending along a first axis (X) and a busbar tab (22; 23; 112) protruding from the cylindrical portion along the first axis (X); a fuse (41) housed inside the cylindrical portion (21); a fuse tab (32; 43; 111) electrically connected to the fuse (41) and protruding outside the cylindrical portion (21) along the first axis (X); a cylindrical resin housing (10) that houses the negative-side busbar (20); and a cylindrical magnetic body (101; 102) provided in the housing at a portion that radially overlaps with the fuse tab (32; 43; 111) over the entire length of the fuse tab along the first axis (X).

[0078] According to Supplementary Note 1, a cylindrical magnetic body (first magnetic body 101 or second magnetic body 102 in FIG. 1 ) is provided in the housing so as to radially overlap the fuse tab (positive connection tab 32 or male tab 43 in FIG. 1 , male tab 111 in FIG. 15 ) over the entire length of the fuse tab. Therefore, while the use of a resin housing reduces the overall weight of the electrical junction box, electromagnetic noise radiated from the fuse tab protruding outside the cylindrical portion can be suppressed by the magnetic body that surrounds the fuse tab over its entire length.

[0079] (Appendix 2) The electrical connection box (1) according to Appendix 1, wherein the housing (10) includes holding claws (14; 15) that hold the magnetic body (101; 102), and the holding claws (14; 15) include: protrusions (14a; 15a) that protrude radially outward from the outer circumferential surface of the housing (10) at locations that overlap with the cylindrical portion (21) in the radial direction; extensions (14b; 15b) that extend from tips of the protrusions (14a; 15a) along the first axis (X); and claws (14c) that protrude radially inward from the extensions (14b; 15b).

[0080] According to Appendix 2, the retaining claw is configured so that an extension extends from a protruding portion that protrudes from the outer surface of the housing at a portion that radially overlaps with the tubular portion, and therefore the retaining claw can hold the magnetic material that is arranged to cover the periphery of the fuse tab over the entire length of the fuse tab.

[0081] The embodiments disclosed herein are illustrative in all respects, and the present invention is not limited to these examples. That is, the scope of the present invention is defined by the claims, and it is intended to include all modifications within the meaning and scope of the claims.

[0082] DESCRIPTION OF SYMBOLS 1 Electrical junction box 10 Housing 11 Housing body 11a First end 11b Second end 12 First end plate 12a First connecting tubular portion 12b Second connecting tubular portion 13 Second end plate 13a Second connecting tubular portion 14 First holding claw (holding claw) 14a First protruding portion 14b First extending portion 14c First claw portion 15 Second holding claw (holding claw) 15a Second protruding portion 15b Second extending portion 15c Second claw portion 16 First external terminal 17 Second external terminal 20 Negative side bus bar 21 Cylindrical portion 21a First end 21b Second end 22 Negative side connecting tab (bus bar tab) 23 Bus bar side male tab (bus bar tab) 30 Positive side bus bar 31 Fixing portion 31a Through hole 32 Positive side connection tab (fuse tab and first fuse tab) 40 Composite fuse 41 Fuse 42 Fuse body 42a First end surface 42b Second end surface 43 Male tab (fuse tab and second fuse tab) 44 Fixing tab 51 First connection portion 51a Tip 52 Second connection portion 52a Tip 53 Fixing portion 53a Fixing hole 53AX Fixing axis 53b First arc end 53c Second arc end 54 Fixing piece 54a Step 55 Opening 56 Overlapping portion 61 Bolt 62 Nut 71 Device 72 Device 80 Wire harness 81 Connector 82 Connector 83a Positive side electric wire 83b Negative side electric wire 90 Wire harness 91 Connector 92 Connector 93a Positive side electric wire 93b Minus side electric wire 101 First magnetic body (magnetic body) 102 Second magnetic body (magnetic body) 111 Male tab (fuse tab) 112 Bus bar side male tab (bus bar tab) X First axis X1 First direction X2 First opposite direction Y Second axis Z Third axis

Claims

1. An electrical connection box comprising: a negative bus bar having a cylindrical portion extending along a first axis and a bus bar tab protruding along the first axis from a circumferential portion of the cylindrical portion; a plurality of fuses housed inside the cylindrical portion; a fuse tab electrically connected to the plurality of fuses and protruding outside the cylindrical portion along the first axis; a resin housing that houses the negative bus bar; and a magnetic body provided in the housing at a position corresponding to the periphery of the fuse tab protruding outside the cylindrical portion.

2. The electrical junction box according to claim 1, wherein the magnetic material is provided on the entire periphery of the housing.

3. The electrical junction box according to claim 1, wherein the magnetic body is provided in a range that includes the entire area along the first axis of the fuse tab that protrudes from the cylindrical portion in the housing.

4. The electrical junction box according to claim 1, wherein the housing has holding claws for holding the magnetic body.

5. An electrical junction box as described in claim 1, wherein the fuse tabs include a first fuse tab protruding outward from a first end of the cylindrical portion and a second fuse tab protruding outward from a second end of the cylindrical portion, and the magnetic body includes a first magnetic body provided in a portion of the housing corresponding to the periphery of the first fuse tab, and a second magnetic body provided in a portion of the housing corresponding to the periphery of the second fuse tab.

6. The electrical junction box according to claim 1, wherein the fuse tab protrudes only from the first end of the cylindrical portion.

Images