Electrical connection box

Abstract

An electrical connection box (11) comprises: a case (21) made of a resin material; and an electrical circuit component (31) accommodated and held in the case (21). The electrical circuit component (31) includes a contactor (32) capable of generating a magnetic field and a current sensor (33). The electrical connection box (11) is provided with a metal plate (41) interposed between the contactor (32) and the current sensor (33). The case (21) has a covering part (24) that covers the principal surface of the metal plate (41) inside the case (21).

Description

Electrical junction box

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

[0002] Conventionally, an electrical junction box has been provided in, for example, a battery pack of a vehicle (see, for example, Patent Document 1). The battery pack includes a battery pack case, an electrical junction box, and a plurality of battery cells.

[0003] The electrical junction box includes a resin case and electrical circuit components housed within the case. The electrical circuit components include contactors, which are a type of relay, current sensors, bus bars, etc. The electrical circuit components monitor the current and temperature of the battery cells to optimize input and output of the battery pack.

[0004] JP 2013-16467 A

[0005] However, the contactor described above has a coil portion inside, which generates a magnetic field during operation. The detection accuracy of the current sensor decreases when the current sensor is affected by the magnetic field. This is a major problem, especially when attempting to reduce the size of an electrical junction box. To address this issue, for example, a metal plate can be installed inside the case to separate the contactor and the current sensor. However, if a metal plate is installed inside the case, there is a risk that the metal plate may come into contact with other electrical components. Specifically, for example, there is a risk that the bus bar may become electrically connected to the metal plate. Furthermore, there is a risk that a flexible insulated wire may be damaged by rubbing against the corners of the metal plate.

[0006] An object of the present disclosure is to provide an electrical junction box that can prevent contact between an electric circuit component and a metal plate while suppressing a decrease in the detection accuracy of a current sensor.

[0007] The electrical connection box of the present disclosure comprises a case made of a resin material and electrical circuit components housed and held within the case, the electrical circuit components including a current sensor and a magnetic field generating component that generates a magnetic field, and comprises a metal plate interposed between the magnetic field generating component and the current sensor, and the case has a covering portion that covers the main surface of the metal plate inside the case.

[0008] According to the electrical junction box of the present disclosure, it is possible to prevent contact between the electric circuit components and the metal plate while suppressing a decrease in the detection accuracy of the current sensor.

[0009] Fig. 1 is an exploded perspective view of an electrical junction box according to one embodiment. Fig. 2 is a plan view of a lower case and electrical circuit components according to one embodiment. Fig. 3 is a perspective view of the lower case and electrical circuit components according to one embodiment. Fig. 4 is a partial cross-sectional view of an electrical junction box according to one embodiment. Fig. 5 is a cross-sectional view taken along line 5-5 in Fig. 4.

[0010] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described. The present disclosure provides an electrical junction box: [1] comprising a case made of a resin material and electrical circuit components housed and held within the case, the electrical circuit components including a current sensor and a magnetic field generating component that generates a magnetic field, the electrical junction box comprising a metal plate interposed between the magnetic field generating component and the current sensor, and the case having a covering portion that covers a main surface of the metal plate inside the case.

[0011] According to this configuration, since the metal plate is interposed between the magnetic field generating component and the current sensor, the current sensor is prevented from being affected by the magnetic field generated by the magnetic field generating component. This prevents a decrease in the detection accuracy of the current sensor. Furthermore, since the case has a covering portion that covers the main surface of the metal plate inside the case, the metal plate is prevented from coming into direct contact with other electrical circuit components. This prevents, for example, a bus bar connecting the magnetic field generating component and the current sensor from being electrically connected to the metal plate. Furthermore, for example, damage to a flexible insulated electric wire caused by rubbing against the corners of the metal plate is prevented.

[0012] [2] In the above [1], the case may have an insertion opening through which the metal plate can be inserted between the coated portions from the outside, and a storage bottom portion that connects the coated portions at the tip end in the insertion direction of the metal plate.

[0013] According to this configuration, the case has an insertion port through which a metal plate can be inserted between the coated portions from the outside, and a storage bottom portion that connects the coated portions at the tip end in the insertion direction of the metal plate, so that the metal plate can be easily positioned by inserting it through the insertion port.

[0014] [3] In the above [1] or [2], the electrical circuit component may include a bus bar connecting the magnetic field generating component and the current sensor, and the bus bar may be arranged so that its main surface faces the bottom surface inside the case.

[0015] According to this configuration, the bus bar connecting the magnetic field generating component and the current sensor is arranged so that its main surface faces the bottom surface of the case, making it easy to interpose a metal plate between the magnetic field generating component and the current sensor. That is, for example, in a configuration in which the bus bar is arranged so that its main surface is perpendicular to the bottom surface of the case, the bus bar gets in the way, making it difficult to interpose a metal plate between the magnetic field generating component and the current sensor, but this can be avoided.

[0016] [4] In any one of [1] to [3] above, the metal plate may have a plurality of different planar portions arranged to surround the current sensor or the magnetic field generating component.

[0017] According to this configuration, the metal plate has multiple different planar portions arranged to surround the current sensor or the magnetic field generating component, so that the magnetic field generating component and the current sensor can be neatly separated compared to when the planar portion is a single metal plate.

[0018] [5] In the above [4], the metal plate may have a bent portion connecting the plurality of different planar portions together. According to this configuration, since the metal plate has a bent portion connecting the plurality of different planar portions together, the number of parts can be reduced compared to, for example, when the plurality of different planar portions are each independent separate members.

[0019] [6] In any one of [1] to [5] above, the metal plate may be arranged so as to block both the surface of the current sensor facing the magnetic field generating component and the surface of the magnetic field generating component facing the current sensor.

[0020] According to this configuration, the metal plate is arranged to completely block the surface of the current sensor facing the magnetic field generating component and the surface of the magnetic field generating component facing the current sensor, which makes it possible to more effectively prevent the current sensor from being affected by the magnetic field than in a configuration where only a portion of the surface is not blocked, thereby more effectively preventing a decrease in the detection accuracy of the current sensor.

[0021] [Details of the Embodiments of the Present Disclosure] 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 of the components may be exaggerated or simplified. Furthermore, the dimensional ratios of each part may differ between drawings. In this specification, "parallel," "orthogonal," and "circular" do not only refer to strictly parallel, orthogonal, or circular, but also include roughly parallel, orthogonal, or circular within the scope of the present embodiment's effects. The present invention is not limited to these examples, but is defined by the claims, and all modifications within the meaning and scope of the claims are intended to be included.

[0022] 1, the electrical junction box 11 includes a case 21, electrical circuit components 31, and a metal plate 41. The electrical junction box 11 of this embodiment is provided in a battery pack mounted on a vehicle such as an electric automobile. That is, the electrical junction box 11 is housed in a battery pack case together with a plurality of battery cells.

[0023] (Configuration of case 21) The case 21 has a lower case 22 and an upper case 23. The lower case 22 and the upper case 23 are each made of a resin material. The lower case 22 is formed in the shape of a rectangular flat plate. The upper case 23 is configured so that it can be assembled above the lower case 22. The upper case 23 has a rectangular cylindrical side wall portion 23a that corresponds to the periphery of the lower case 22, and an upper wall portion 23b that closes the upper end of the side wall portion 23a.

[0024] (Configuration of Electrical Circuit Components 31) The electrical circuit components 31 are arranged on the upper surface of the lower case 22, which is the bottom surface 21a inside the case 21, and are housed and held within the case 21.

[0025] 2 and 3 , the electric circuit components 31 include a contactor 32 as a magnetic field generating component that generates a magnetic field, a current sensor 33, and a bus bar 34. Note that in each drawing of this embodiment, only one contactor 32, two current sensors 33, and one bus bar 34 are illustrated, and the other electric circuit components 31 are not illustrated. That is, the electric circuit components 31 included in the electric junction box 11 may include, for example, multiple contactors 32 and multiple bus bars 34, or may include other electric circuit components 31 such as flexible coated wires and fuses. Furthermore, although the current sensor 33 in this embodiment includes a Hall element, the current sensor 33 is not limited to this and may be a through-type current sensor.

[0026] In this embodiment, the contactor 32 and the two current sensors 33 are arranged side by side along one side, more specifically, the long side, of the lower case 22. The contactor 32 is connected via a bus bar 34 to a connection terminal 33 a of one of the two current sensors 33 connected in series.

[0027] 3 , the bus bar 34 is disposed such that a main surface of the bus bar 34 faces the bottom surface 21 a of the case 21. Specifically, the bus bar 34 has a first connection end 34 a, a second connection end 34 b, and a connecting portion 34 c that connects the first connection end 34 a and the second connection end 34 b. The main surface of the connecting portion 34 c is disposed such that it faces the bottom surface 21 a of the case 21. The first connection end 34 a rises from the connecting portion 34 c so that the main surface of the bus bar 34 is perpendicular to the bottom surface 21 a, and is connected to the contactor 32. The second connection end 34 b rises from the connecting portion 34 c so that the main surface of the bus bar 34 is perpendicular to the bottom surface 21 a, and is connected to the connection terminal 33 a of the current sensor 33.

[0028] 4 and 5 , the metal plate 41 is interposed between the contactor 32 and the current sensor 33. In other words, the metal plate 41 is provided so as to separate the contactor 32 and the current sensor 33.

[0029] The case 21 has a covering portion 24 that covers the main surface of the metal plate 41 inside the case 21. The covering portion 24 in this embodiment is provided on the upper case 23. The covering portion 24 is formed so as to cover the entire main surface of the metal plate 41.

[0030] More specifically, as shown in FIG. 4 , the metal plate 41 has two different planar portions, a first planar portion 41a and a second planar portion 41b, arranged to surround the current sensor 33. The metal plate 41 also has a bent portion 41c connecting the first planar portion 41a and the second planar portion 41b. That is, the metal plate 41 is formed from a single folded component. The first planar portion 41a and the second planar portion 41b extend perpendicularly from the bent portion 41c. The first planar portion 41a of the metal plate 41 is arranged parallel to the short sides of the lower case 22, and the second planar portion 41b is arranged parallel to the long sides of the lower case 22. The metal plate 41 is arranged to surround the current sensor 33 with the edge of the lower case 22. The metal plate 41 is arranged to block both the surface of the current sensor 33 facing the contactor 32 and the surface of the contactor 32 facing the current sensor 33.

[0031] 4 and 5, the first flat portion 41a, which is a part of the metal plate 41, is disposed so as to pass above the connecting portion 34c of the bus bar 34. When viewed from above, the first flat portion 41a is disposed so as to cross the connecting portion 34c extending along the long side of the lower case 22.

[0032] 5, the upper case 23 has an insertion opening 25 through which a metal plate 41 can be inserted from the outside between the covering portions 24, and a housing bottom 26 that connects the covering portions 24 at the leading end in the insertion direction of the metal plate 41. The insertion opening 25 in this embodiment is provided in the upper wall portion 23b of the upper case 23 and opens upward. Note that in this embodiment, the metal plate 41 is fixed by being press-fitted from the insertion opening 25 between the covering portions 24. For example, a plurality of press-fit protrusions (not shown) are provided on the opposing surfaces of the covering portions 24, and the metal plate 41 is held by being sandwiched between these press-fit protrusions.

[0033] Next, we will explain the operation of the electrical junction box 11 configured as described above. The electrical circuit components 31 of the electrical junction box 11 are electrically connected to the battery cells housed in the battery pack case together with the electrical junction box 11. The electrical circuit components 31 of the electrical junction box 11 monitor the current values, temperatures, etc. of the battery cells, thereby achieving optimal input and output for the battery pack.

[0034] Next, the effects of the above embodiment are described below. (1) The metal plate 41 interposed between the contactor 32 and the current sensor 33 prevents the current sensor 33 from being affected by the magnetic field generated by the contactor 32. This prevents a decrease in the detection accuracy of the current sensor 33. This eliminates the need to place the contactor 32 and the current sensor 33 far apart, facilitating the miniaturization of the electrical junction box 11. Furthermore, the case 21 has a covering portion 24 that covers the main surface of the metal plate 41 inside the case 21, preventing the metal plate 41 from coming into direct contact with other electrical circuit components 31. This prevents, for example, the bus bar 34 connecting the contactor 32 and the current sensor 33 from being electrically connected to the metal plate 41. Furthermore, even if the electrical junction box 11 vibrates while the vehicle is traveling, for example, this prevents damage to flexible covered wires (not shown) due to friction with corners of the metal plate 41.

[0035] (2) The case 21 has an insertion opening 25 through which the metal plate 41 can be inserted from the outside between the covering portions 24, and a housing bottom 26 that connects the covering portions 24 at the leading end in the insertion direction of the metal plate 41. Therefore, the metal plate 41 can be easily positioned by inserting it through the insertion opening 25.

[0036] (3) The bus bar 34 connecting the contactor 32 and the current sensor 33 is disposed so that the main surface of the bus bar 34 faces the bottom surface 21 a inside the case 21, and therefore the metal plate 41 can be easily interposed between the contactor 32 and the current sensor 33. That is, for example, in a configuration in which the bus bar 34 is disposed so that the main surface of the bus bar 34 is perpendicular to the bottom surface 21 a, the bus bar gets in the way, making it difficult to interpose the metal plate 41 between the contactor 32 and the current sensor 33, but this can be avoided.

[0037] (4) The metal plate 41 has two different planar portions, the first planar portion 41a and the second planar portion 41b, which are arranged to surround the current sensor 33. Therefore, for example, compared to when the planar portion is a single metal plate, the contactor 32 and the current sensor 33 can be neatly separated.

[0038] (5) Since the metal plate 41 has a bent portion 41c that connects the first planar portion 41a and the second planar portion 41b, the number of parts can be reduced compared to, for example, when the first planar portion 41a and the second planar portion 41b are each separate, independent components.

[0039] (6) The metal plate 41 is disposed so as to completely block the surface of the current sensor 33 facing the contactor 32 and the surface of the contactor 32 facing the current sensor 33. Therefore, compared to a configuration in which only a portion of the surface is not blocked, the current sensor 33 can be more effectively prevented from being affected by the magnetic field generated by the contactor 32. Therefore, a decrease in the detection accuracy of the current sensor 33 can be more effectively prevented.

[0040] This embodiment can be implemented with the following modifications. This embodiment and the following modifications can be implemented in combination with each other to the extent that there is no technical contradiction. In the above embodiment, the case 21 has the insertion opening 25 through which the metal plate 41 can be inserted from the outside between the covering portions 24, and the housing bottom 26 that connects the covering portions 24 at the tip end of the metal plate 41 in the insertion direction, but this is not limited to this. For example, the metal plate 41 may be provided so as to be covered by the covering portion of the upper case 23 by insert molding when the upper case 23 is molded.

[0041] In the above embodiment, the insertion opening 25 is provided in the upper wall portion 23b of the upper case 23 and opens upward, but this is not limited thereto, and may be provided in the side wall portion 23a and open to the side. Also, the covering portion 24, the insertion opening 25, and the housing bottom portion 26 may be provided in the lower case 22, and the insertion opening 25 may open downward.

[0042] In the above embodiment, the bus bar 34 connecting the contactor 32 and the current sensor 33 is arranged so that the main surface of the bus bar 34 faces the bottom surface 21 a inside the case 21, but this is not limited to this, and the main surface of the bus bar 34 may be arranged so that it is perpendicular to the bottom surface 21 a.

[0043] In the above embodiment, the metal plate 41 has the first planar portion 41a and the second planar portion 41b as two different planar portions arranged to surround the current sensor 33. However, this is not limited to this, and the metal plate 41 may have, for example, three or more different planar portions. Also, for example, the planar portion may be a single metal plate.

[0044] In the above embodiment, the metal plate 41 has a bent portion 41c that connects the first planar portion 41a and the second planar portion 41b, but this is not limited to this. For example, the first planar portion 41a and the second planar portion 41b may each be separate, independent members.

[0045] In the above embodiment, the metal plate 41 is arranged so as to block the entire surface of the current sensor 33 facing the contactor 32 and the entire surface of the contactor 32 facing the current sensor 33, but this is not limited to this and the metal plate 41 may be configured to block only a portion of the surface.

[0046] In the above embodiment, the electric circuit component 31 includes the contactor 32 as a magnetic field generating component, but is not limited to this and may include other magnetic field generating components such as a core that generates a magnetic field. In this case, the metal plate 41 is of course interposed between the other magnetic field generating component such as a core and the current sensor 33.

[0047] In the above embodiment, the metal plate 41 is fixed by being pressed into the space between the insertion port 25 and the covering portion 24, but this is not limited to this. The metal plate 41 may be configured to be prevented from coming out by a claw or the like while inserted between the insertion port 25 and the covering portion 24.

[0048] In the above embodiment, the electrical connection box 11 is provided in a battery pack mounted on a vehicle such as an electric vehicle, but this is not limited to this and the electrical connection box 11 may be provided in other devices.

[0049] The contactor 32 in the illustrated non-limiting embodiment is an example of an electromagnetic coil-type magnetic noise source or a non-sensor magnetic noise source. As shown in Figures 4 and 5, the covering portion 24 and the housing bottom 26 may be referred to as a partition configured to divide the internal space of the case 21 into a magnetic noise source compartment (e.g., the space on the left in Figure 5) for housing the electromagnetic coil-type magnetic noise source, which may be the contactor 32, and a current sensor compartment (e.g., the space on the right in Figure 5) for housing the current sensor 33. This partition may extend linearly from the top surface of the upper case 23 to the bottom surface of the lower case 22, as shown in Figure 5, and may have, for example, a hollow double-wall structure.

[0050] The metal plate 41 in the illustrated non-limiting embodiment is an example of a magnetic noise shield plate having an outermost edge, a thickness, a width, and a length, and may optionally have a bent corner or an alignment corner. As shown in Figures 1, 4, and 5, the insertion opening 25, the covering portion 24, and the receiving bottom 26 of the case 21 are an example of a slot-shaped holder. This slot-shaped holder may be configured to accommodate the entire metal plate 41 so that the outermost edge of the metal plate 41 does not protrude beyond the outline or outermost surface of the case 21 and so that the surface of the metal plate 41 is not exposed to the internal space of the case 21. This slot-shaped holder may have a slot width that matches or corresponds to the thickness of the metal plate 41, a slot depth that matches or corresponds to the width of the metal plate 41, and a slot length that matches or corresponds to the length of the metal plate 41. If the metal plate 41 has a bent corner or an alignment corner, the slot-shaped holder may have a bent space that corresponds to the bent corner or alignment corner of the metal plate 41. 5, the insertion opening 25 on the outer surface of the case 21 is configured to allow insertion into the slot-like holder from outside the case 21, and may be referred to as a slot-like entrance. Optionally, the insertion opening 25 of the case 21 may be configured to allow removal of the metal plate 41 from the slot-like holder to outside the case 21.

[0051] DESCRIPTION OF SYMBOLS 11 Electrical junction box 21 Case 21a Bottom surface 22 Lower case 23 Upper case 23a Side wall portion 23b Upper wall portion 24 Covering portion 25 Insertion opening 26 Housing bottom portion 31 Electric circuit component 32 Contactor (magnetic field generating component) 33 Current sensor 33a Connection terminal 34 Bus bar 34a First connection end portion 34b Second connection end portion 34c Linking portion 41 Metal plate 41a First flat portion (flat portion) 41b Second flat portion (flat portion) 41c Bent portion

Claims

1. An electrical junction box comprising a case made of a resin material and electrical circuit components housed and held within the case, the electrical circuit components including a current sensor and a magnetic field generating component that generates a magnetic field, the electrical junction box further comprising a metal plate interposed between the magnetic field generating component and the current sensor, the case having a covering portion covering the main surface of the metal plate inside the case.

2. An electrical connection box as described in claim 1, wherein the case has an insertion opening through which the metal plate can be inserted from the outside between the coated portions, and a housing bottom that connects the coated portions at the tip end in the insertion direction of the metal plate.

3. The electrical connection box according to claim 1, wherein the electric circuit components include a bus bar that connects the magnetic field generating component and the current sensor, and the bus bar is arranged so that a main surface of the bus bar faces a bottom surface inside the case.

4. The electrical connection box according to claim 1, wherein the metal plate has a plurality of different planar portions arranged so as to surround the current sensor or the magnetic field generating component.

5. The electrical connection box according to claim 4, wherein the metal plate has bent portions connecting the plurality of different planar portions together.

6. The electrical junction box according to claim 1, wherein the metal plate is arranged so as to block both a surface of the current sensor facing the magnetic field generating component and a surface of the magnetic field generating component facing the current sensor.

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