Electrical connection box

Abstract

The present disclosure provides an electrical connection box in which the number of components can be reduced. An electrical connection box (11) according to one aspect of the present disclosure includes: a plate-shaped first base member (22); and a basic electric circuit component (23) disposed on the first base member (22). The basic electric circuit component (23) includes a first metal plate (27) and a second metal plate (28) that are stacked and electrically connected to each other. The electrical connection box (11) is provided with a self-tapping screw (51) capable of fixing the first metal plate (27) and the second metal plate (28) while forming a female thread (27a) in the first metal plate (27).

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 is housed in a battery pack case together with multiple battery cells. The electrical junction box includes, for example, a case and electrical circuit components arranged on a base member that forms the bottom of the case. The electrical circuit components are connected to the multiple battery cells. The electrical circuit components include, for example, multiple relays, fuses, bus bars, etc. The electrical circuit components monitor the current value, temperature, etc. of the battery cells to achieve optimal input and output.

[0004] JP 2013-16467 A

[0005] In the electrical junction box described above, metal bus bars are often used instead of thin wires because they handle large currents. Multiple metal plates are stacked and electrically connected in many locations. These multiple metal plates are generally firmly fastened together with nuts and bolts to reduce contact resistance and ensure stable connections. However, the need for multiple nut-bolt pairs increases the number of parts, which is a problem.

[0006] An object of the present disclosure is to provide an electrical junction box that can reduce the number of parts.

[0007] The electrical connection box of the present disclosure comprises a plate-shaped base member and an electrical circuit component arranged on the base member, the electrical circuit component being an electrical connection box including a plurality of metal plates that are stacked and electrically connected, and comprising a tapping screw that can fix the plurality of metal plates while forming a female thread in at least one of the plurality of metal plates.

[0008] According to the electrical junction box of the present disclosure, the number of parts can be reduced.

[0009] Fig. 1 is a perspective view of an electrical junction box according to one embodiment. Fig. 2 is an exploded perspective view of the electrical junction box according to one embodiment. Fig. 3 is a plan view of a first circuit unit and a heat dissipation metal plate according to one embodiment. Fig. 4 is a cross-sectional view taken along line 4-4 in Fig. 3. Fig. 5 is a partial cross-sectional view of an electrical junction box according to one embodiment at a pre-manufacturing stage.

[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 plate-shaped base member and an electrical circuit component disposed on the base member, the electrical circuit component including a plurality of metal plates that are stacked and electrically connected, and a tapping screw that can fix the plurality of metal plates by forming a female thread in at least one of the plurality of metal plates.

[0011] According to this configuration, a tapping screw is provided that can secure multiple metal plates while forming a female thread in at least one of the multiple metal plates that are stacked and electrically connected, eliminating the need for nuts and pre-forming the female thread, thereby reducing the number of parts while suppressing an increase in processing man-hours.

[0012] [2] In the above [1], the base member may have a partition portion that separates a space where shavings are generated by the tapping screw from a space where other electric circuit components are arranged.

[0013] According to this configuration, the base member has a partition that separates the space where shavings are generated by the tapping screw from the space where other electric circuit components are arranged, thereby preventing the shavings from coming into contact with the other electric circuit components, and thus preventing, for example, unintentional electrical connection between the other electric circuit components.

[0014] [3] In the above [2], a closing part may be provided that, together with the partition part, closes the space in which shavings are generated by the tapping screw. According to this configuration, the electrical connection box includes, together with the partition part, a closing part that closes the space in which shavings are generated by the tapping screw, so that, for example, shavings generated by the tapping screw can be prevented from scattering outside the closed space.

[0015] [4] In the above [3], the closing portion may be a heat dissipating metal plate attached below the base member. According to this configuration, since the closing portion is a heat dissipating metal plate attached below the base member, it is possible to improve heat dissipation while preventing shavings from scattering outside the closed space. In this way, by giving the heat dissipating metal plate, which has the function of improving heat dissipation, the function of preventing shavings from scattering, it is possible to reduce the number of parts compared to when the two are separate parts.

[0016] [5] In any one of [1] to [4] above, the plurality of metal plates include a first metal plate having a female screw hole in which the female screw is formed by the tapping screw, and a second metal plate having an insertion hole through which the tapping screw is inserted, and the first metal plate may be thicker than the second metal plate.

[0017] According to this configuration, the first metal plate having the female screw hole in which the female screw is formed by the tapping screw is thicker than the second metal plate having the insertion hole through which the tapping screw is inserted, allowing the female screw to be long. This allows the multiple metal plates to be firmly fixed together. Furthermore, because the second metal plate is thinner than the first metal plate, it is easier to perform processes such as bending.

[0018] [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.

[0019] 1 and 2 , the electrical junction box 11 includes a first circuit unit 21, a second circuit unit 31, and a heat dissipation metal plate 41. The second circuit unit 31 is stacked on the first circuit unit 21. The heat dissipation metal plate 41 is attached below the first circuit unit 21.

[0020] The electrical junction box 11 of this embodiment is provided in a battery pack mounted on a vehicle such as an electric automobile, etc. That is, the electrical junction box 11 is housed in a battery pack case together with a plurality of battery cells.

[0021] The drawing also shows a first axis X, a second axis Y perpendicular to the first axis X, and a third axis Z perpendicular to the first axis X and the second axis Y. The drawing also shows a longitudinal direction X1, which is one direction along the first axis X, and a lateral direction Y1, which is one direction along the second axis Y. The drawing also shows an upward direction Z1 along the third axis Z, and a downward direction Z2, which is the opposite direction to the upward direction Z1.

[0022] (Configuration of first circuit unit 21) As shown in Figures 2 and 3, the first circuit unit 21 has a first base member 22 as a plate-shaped base member, and basic electrical circuit components 23 that are arranged on the first base member 22 and form part of the electrical circuit components.

[0023] The first base member 22 is made of a resin material. When viewed from above, the first base member 22 is formed in a rectangular shape. The first base member 22 has projections and recesses that allow the basic electric circuit components 23 to be positioned and arranged thereon. The first base member 22 forms the bottom surface of the case in the electrical junction box 11. The first base member 22 also has side wall portions 22a that protrude upward from its edge. The side wall portions 22a, together with the side walls of the upper case (not shown), form the side surfaces of the case in the electrical junction box 11.

[0024] The basic electric circuit components 23 are electric circuit components that are always required regardless of the grade or options of the vehicle in which they are installed. The basic electric circuit components 23 include, for example, a relay 24, a fuse 25, a bus bar 26, and the like.

[0025] (Configuration of second circuit unit 31) As shown in Figures 1 and 2, the second circuit unit 31 has a plate-shaped second base member 32 and additional electric circuit components 33 that are arranged on the second base member 32 and that form part of the electric circuit components.

[0026] The second base member 32 is made of a resin material. The second base member 32 is formed in a rectangular shape when viewed from above. When viewed from above, the second base member 32 is formed in a rectangular shape that fits within the range of the rectangular shape of the first base member 22 and is slightly shorter than the first base member 22. The second base member 32 has irregularities that allow the additional electric circuit components 33 to be positioned and arranged thereon.

[0027] The additional electric circuit components 33 are electric circuit components that are added to the basic electric circuit components 23 depending on the grade and options of the vehicle to be installed. The additional electric circuit components 33 include, for example, a control unit 34 including a microcomputer and bus bars 35. Note that the number and arrangement of the basic electric circuit components 23 and the additional electric circuit components 33 in each drawing are not necessarily strictly those illustrated, but are shown as an example.

[0028] The second circuit unit 31 is stacked on the first circuit unit 21 and fixed to the first circuit unit 21. In the second circuit unit 31, additional electric circuit components 33 are connected to the basic electric circuit components 23.

[0029] (Configuration of Heat Dissipating Metal Plate 41) The heat dissipating metal plate 41 is made of a metal material with high heat dissipation properties, such as aluminum, etc. The heat dissipating metal plate 41 is formed, for example, by pressing an aluminum plate.

[0030] 3, the heat dissipating metal plate 41 is attached below the first base member 22. The heat dissipating metal plate 41 is formed so as to cover the entire area of ​​the underside of the first base member 22. In other words, the heat dissipating metal plate 41 is formed to cover the entire area of ​​the first base member 22 when viewed from above. The heat dissipating metal plate 41 is formed in a rectangular shape that is slightly larger than the first base member 22 in both directions along the first axis X and in both directions along the second axis Y.

[0031] 4 , the basic electric circuit component 23 of this embodiment includes a first metal plate 27 and a second metal plate 28 as a plurality of overlapping and electrically connected metal plates. The first metal plate 27 and the second metal plate 28 are, for example, connection terminals of the relay 24, connection terminals of the fuse 25, bus bars 26, etc., and in this embodiment, they are configured by two types of bus bars 26.

[0032] The first metal plate 27 and the second metal plate 28 are electrically connected while being stacked on top of each other on the first base member 22. More specifically, the first metal plate 27 is disposed so as to abut against the upper surface of the first base member 22. The second metal plate 28 is disposed so as to abut against the upper surface of the first metal plate 27.

[0033] The electrical junction box 11 includes a tapping screw 51 that fastens the first metal plate 27 and the second metal plate 28 together while forming a female thread 27a in the first metal plate 27. The tapping screw 51 of this embodiment is capable of forming the female thread 27a in the first metal plate 27 by being rotated about the third axis Z and moved downward in the Z2 direction.

[0034] More specifically, as shown in FIG. 5 , the second metal plate 28 has an insertion hole 28a through which a tapping screw 51 is inserted. The inner diameter of the insertion hole 28a is set slightly larger than the outer diameter of the tapping screw 51. The first metal plate 27 also has a female thread hole 27b in which a female thread 27a (see FIG. 4) is formed by the tapping screw 51. The female thread hole 27b is a hole before the female thread 27a is formed. In other words, the female thread hole 27b is a hole formed, for example, by punching the first metal plate 27 in the downward direction Z2, and is a simple hole without a groove formed on the inner circumferential surface. The inner diameter of the female thread hole 27b is set smaller than the inner diameter of the insertion hole 28a and is set so that the female thread 27a can be formed by the tapping screw 51.

[0035] The first metal plate 27 is formed to be thicker than the second metal plate 28. Specifically, the thickness of the first metal plate 27 along the third axis Z is set to be larger than the thickness of the second metal plate 28 along the third axis Z.

[0036] 4, the first base member 22 has a partition 22b that separates a space S1 where shavings are generated by the tapping screw 51 from a space S2 where other basic electric circuit components 23 are arranged. The partition 22b is formed by the upper edge of a through hole 22c formed in the first base member 22. In other words, the space S1 where shavings are generated by the tapping screw 51 is a space below the first metal plate 27 in the downward direction Z2, and the portion of the underside of the first metal plate 27 that abuts against the periphery of the female thread 27a is the partition 22b.

[0037] The space S1 where chips are generated by the tapping screw 51 is closed together with the partition portion 22b by the heat dissipation metal plate 41 serving as a blocking portion. That is, the lower end of the through hole 22c of the first base member 22 is closed by the heat dissipation metal plate 41.

[0038] Next, we will explain the operation of the electrical junction box 11 configured as described above. The electrical junction box 11 electrically connects the electrical circuit components, including the basic electrical circuit components 23 and the additional electrical circuit components 33, to the battery cells housed in the battery pack case together with the electrical junction box 11. The electrical circuit components then monitor the current values, temperatures, etc. of the battery cells to achieve optimal input and output.

[0039] Furthermore, if the additional electric circuit components 33 required for higher grades or as options are not required, the electric connection box 11 will be housed in the battery pack case without the second circuit unit 31 provided.

[0040] Next, the effects of the above embodiment are described below. (1) The first metal plate 27 and the second metal plate 28, which are multiple metal plates, are stacked and electrically connected. The electrical junction box 11 includes tapping screws 51 that can fasten the first metal plate 27 and the second metal plate 28 together while forming female threads 27a in the first metal plate 27. This eliminates the need for nuts and pre-forming the female threads 27a. This makes it possible to reduce the number of parts while suppressing an increase in the number of processing steps.

[0041] (2) The first base member 22 has a partition portion 22b that separates the space S1 where shavings are generated by the tapping screws 51 from the space S2 where the other basic electric circuit components 23 are arranged. This prevents the shavings from coming into contact with the other basic electric circuit components 23. This prevents, for example, the other basic electric circuit components 23 from being unintentionally electrically connected to each other.

[0042] (3) The electrical connection box 11 includes the heat dissipating metal plate 41 as a blocking portion that, together with the partition portion 22b, blocks the space S1 where shavings are generated by the tapping screws 51. Therefore, for example, it is possible to prevent shavings generated by the tapping screws 51 from scattering outside the closed space.

[0043] (4) The blocking portion is the heat dissipation metal plate 41 attached under the first base member 22, so that it is possible to prevent shavings from scattering outside the blocked space while improving heat dissipation. In this way, by giving the heat dissipation metal plate 41, which has the function of improving heat dissipation, the function of preventing shavings from scattering, it is possible to reduce the number of parts compared to when each part is a separate part.

[0044] (5) The first metal plate 27, which has the female thread hole 27b in which the female thread 27a is formed by the tapping screw 51, is thicker than the second metal plate 28, which has the insertion hole 28a through which the tapping screw 51 is inserted, and therefore the female thread 27a can be made longer. This allows the first metal plate 27 and the second metal plate 28 to be firmly fixed together. Furthermore, because the second metal plate 28 is thinner than the first metal plate 27, it is easier to perform processes such as bending.

[0045] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction. In the above embodiment, the first base member 22 has the partition portion 22b that separates the space S1 where shavings are generated by the tapping screw 51, but this is not limited to this, and the first base member 22 may be configured without the partition portion 22b.

[0046] In the above embodiment, the partition 22b is configured by the upper edge of the through hole 22c formed in the first base member 22, against whose upper surface the first metal plate 27 abuts, but is not limited to this and may be changed to another configuration. For example, the partition may be a partition wall erected from the first base member 22 in the upward direction Z1 so as to separate a space where shavings are generated by the tapping screw 51 from a space where other basic electric circuit components 23 are arranged.

[0047] In the above embodiment, the electrical junction box 11 includes the heat dissipating metal plate 41 as a closing portion that closes the space S1 where shavings are generated by the tapping screw 51 together with the partition portion 22b, but is not limited to this and may have a configuration that does not include a closing portion. In other words, the space S1 may be open to the outside.

[0048] In the above embodiment, the blocking portion that blocks the space S1 is a heat dissipating metal plate 41 attached under the first base member 22, but this is not limited to this and may be a separate member from the heat dissipating metal plate 41.

[0049] In the above embodiment, the first metal plate 27 having the female screw holes 27b is thicker than the second metal plate 28 having the insertion holes 28a, but this is not limited thereto. For example, the first metal plate 27 and the second metal plate 28 may have the same thickness. Also, for example, the first metal plate 27 may be thinner than the second metal plate 28.

[0050] In the above embodiment, the multiple metal plates that are stacked and electrically connected are the first metal plate 27 and the second metal plate 28, but this is not limited to this. For example, the configuration may be such that three or more metal plates are connected by tapping screws 51.

[0051] In the above embodiment, the electric junction box 11 includes the first circuit unit 21 and the second circuit unit 31, but is not limited to this and may be configured without the second circuit unit 31. In this case, the additional electric circuit components 33 may be disposed on the first base member 22.

[0052] In the above embodiment, the electrical junction box 11 is provided with the heat dissipation metal plate 41 attached below the first base member 22, but this is not limited thereto, and the electrical junction box 11 may be configured without the heat dissipation metal plate 41 attached below the first base member 22. Furthermore, although not specifically mentioned in the above embodiment, the electrical junction box 11 may be provided with a heat dissipation metal plate attached above the first base member 22, or may be provided with a heat dissipation metal plate attached above or below the second base member 32.

[0053] In the above embodiment, the heat dissipating metal plate 41 is formed so as to cover the entire area of ​​the lower surface of the first base member 22. However, this is not limited to this, and the heat dissipating metal plate 41 may be smaller than the first base member 22. Furthermore, the electrical junction box 11 may be configured to include a plurality of heat dissipating metal plates.

[0054] In the above embodiment, the basic electric circuit components 23 include, for example, the relay 24, the fuse 25, the bus bar 26, etc. However, the basic electric circuit components 23 are not limited to these and may include other electric circuit components.

[0055] In the above embodiment, the additional electric circuit components 33 include, for example, the control unit 34 including a microcomputer, the bus bar 35, etc. However, the additional electric circuit components 33 are not limited to these and may include other electric circuit components.

[0056] 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.

[0057] 1 and 2, the plate-shaped first base member 22 of the non-limiting embodiment is an example of a first synthetic resin tray having an upper surface or a first mounting surface configured to mount a plurality of basic electric circuit components 23. The plate-shaped second base member 32 of the non-limiting embodiment is an example of a second synthetic resin tray having an upper surface or a second mounting surface configured to mount additional electric circuit components 33. The illustrated non-limiting embodiment of the electrical junction box 11 may be referred to as a stacking-type electrical junction box in which the first circuit unit 21 and the second circuit unit 31 can be stacked.

[0058] In the illustrated non-limiting embodiment, the downward direction Z2 may be referred to as the fastening direction of the tapping screw 51. In the illustrated non-limiting embodiment, the space S1 of the first base member 22 may be referred to as a metal shavings receiver or a waste box that is directly connected to the female screw hole 27b (or the female screw 27a) of the first metal plate 27 in the fastening direction of the tapping screw 51, for example, formed directly below the female screw hole 27b. In the illustrated non-limiting embodiment, the partition portion 22b of the first base member 22 may be referred to as a shavings inlet or a narrow neck portion of the metal shavings receiver.

[0059] The upper surface of the first base member 22 may have a stepped or uneven structure according to the shapes and sizes of the plurality of basic electric circuit components 23 mounted on the first base member 22. For example, as shown in Figures 4 and 5, the upper surface of the first base member 22 may have a recessed portion for accommodating the overlapping connection portion (double-plate portion) of the first metal plate 27 and the second metal plate 28 of the basic electric circuit component 23. The through-hole 22c may be provided so as to penetrate from the bottom surface of this recessed portion to the lower surface of the first base member 22.

[0060] DESCRIPTION OF SYMBOLS 11 Electrical junction box 21 First circuit unit 22 First base member (base member) 22a Side wall portion 22b Partition portion 22c Through hole 23 Basic electric circuit component (constituting part of the electric circuit component) 24 Relay 25 Fuse 26 Bus bar (metal plate) 27 First metal plate (metal plate) 27a Female screw 27b Hole for female screw 28 Second metal plate (metal plate) 28a Insertion hole 31 Second circuit unit 32 Second base member 33 Additional electric circuit component (constituting part of the electric circuit component) 34 Control unit 35 Bus bar 41 Heat dissipation metal plate 51 Tapping screw S1 Space S2 Space X First axis X1 Longitudinal direction Y Second axis Y1 Short direction Z Third axis Z1 Upward direction Z2 Downward direction

Claims

1. An electrical junction box comprising a plate-shaped base member and electrical circuit components arranged on the base member, the electrical circuit components including a plurality of metal plates which are stacked and electrically connected, and a tapping screw capable of fixing the plurality of metal plates while forming a female thread in at least one of the plurality of metal plates.

2. The electrical junction box according to claim 1, wherein the base member has a partition section that separates a space in which shavings are generated by the tapping screw from a space in which other electrical circuit components are arranged.

3. The electrical connection box according to claim 2, further comprising a closing portion that, together with the partition portion, closes a space in which shavings are generated by the tapping screw.

4. The electrical junction box according to claim 3, wherein the closing portion is a heat dissipating metal plate attached under the base member.

5. An electrical connection box as described in claim 1, wherein the plurality of metal plates include a first metal plate having a female thread hole in which the female thread is formed by the tapping screw, and a second metal plate having an insertion hole through which the tapping screw is inserted, and the first metal plate is thicker than the second metal plate.

Images