Power distribution component

Abstract

Disclosed is a power distribution component that is capable of reducing height while securing a deflection amount of an elastic arm part.　A power distribution component 10 includes a bus bar 16, a resin case 12 having a bus bar holding part 14 for holding the bus bar 16, an elastic arm part 26 held by a peripheral wall 18 of the bus bar holding part 14 and allowed to elastically deform to an outer peripheral side of the bus bar holding part 14, and a locking claw 28 provided on the elastic arm part 26 and disposed so as to overlap with the bus bar 16 held by the bus bar holding part 14 in a non-deformed state of the elastic arm part 26. The elastic arm part 26 extends in a circumferential direction of the peripheral wall 18.

Description

Power distribution component

[0001] The present disclosure relates to a power distribution component.

[0002] Conventionally, at appropriate positions in a vehicle, there has been arranged a power distribution component in which a bus bar, which is an energizing member, is held by a resin case. For example, Patent Document 1 discloses a wiring module which is a kind of power distribution component. This wiring module is installed in a battery pack mounted on a vehicle, and includes a resin case covering the upper surface of a single battery group in the battery pack, and a plurality of bus bars held by a plurality of bus bar holding portions provided in the resin case. Through the plurality of bus bars, the electrode terminals of adjacent single batteries are electrically connected.

[0003] By the way, on the peripheral wall of the bus bar holding portion, there are provided an elastic arm portion held in a cantilever beam shape and protruding downward, and a locking claw provided at the protruding end portion of the elastic arm portion. When the bus bar is inserted into the bus bar holding portion from above, when the bus bar abuts against the locking claw, the elastic arm portion elastically deforms to the outer peripheral side and the attachment of the bus bar to the bus bar holding portion is permitted. When the bus bar rides over the locking claw and is arranged in the bus bar holding portion, the elastic arm portion elastically returns, and the locking claw is arranged to overlap the bus bar. Therefore, by the locking claw locking the bus bar, the detachment of the bus bar from the bus bar holding portion is prevented.

[0004] Japanese Unexamined Patent Application Publication No. 2018 - 125157

[0005] However, in the structure of Patent Document 1, since the elastic arm portion has a structure in which the upper end portion is held in a cantilever beam shape on the peripheral wall of the bus bar holding portion in the height direction of the peripheral wall, in order to ensure the amount of deflection of the elastic arm portion to the outer peripheral side, it is necessary to secure the arm length of the elastic arm portion in the height direction of the peripheral wall. Therefore, there is a limit in reducing the height of the peripheral wall of the bus bar holding portion, and thus the back height of the wiring module, and there may be a case where it cannot meet the recent requirement for reducing the back height of the power distribution component.

[0006] Therefore, a power distribution component capable of reducing the back height while ensuring the amount of deflection of the elastic arm portion is disclosed.

[0007] The power distribution component of this disclosure includes a busbar, a resin case having a busbar holding portion for holding the busbar, an elastic arm portion held by the peripheral wall of the busbar holding portion and allowing elastic deformation toward the outer circumference of the busbar holding portion, and a locking claw provided on the elastic arm portion and positioned to overlap the busbar held by the busbar holding portion when the elastic arm portion is stationary, wherein the elastic arm portion extends in the circumferential direction of the peripheral wall.

[0008] According to this disclosure, it is possible to provide a power distribution component that can be made low-profile while ensuring sufficient deflection of the elastic arm.

[0009] Figure 1 is a perspective view showing a power distribution component according to Embodiment 1. Figure 2 is a plan view of the power distribution component of Figure 1. Figure 3 is an exploded perspective view of the power distribution component of Figure 1. Figure 4 is a cross-sectional view taken along line IV-IV of Figure 2. Figure 5 is a perspective view showing the elastic deformation state of the elastic arm portion in the power distribution component of Figure 1. Figure 6 is a partially enlarged perspective view showing one modified example of the elastic arm portion in the power distribution component of Figure 1. Figure 7 is a partially enlarged perspective view showing yet another modified example of the elastic arm portion in the power distribution component of Figure 1. Figure 8 is a partially enlarged perspective view showing yet another modified example of the elastic arm portion in the power distribution component of Figure 1. Figure 9 is a perspective view showing a modified example of the formation area of ​​the elastic arm portion in the power distribution component of Figure 1. Figure 10 is a partial perspective view showing modified examples of the busbar shape and the formation area of ​​the elastic arm portion in the power distribution component of Figure 1. Figure 11 is a longitudinal cross-sectional view showing a power distribution component according to another embodiment, corresponding to Figure 4. Figure 12 is a perspective view showing a power distribution component according to yet another embodiment, before the heat conduction member is assembled. Figure 13 is a longitudinal cross-sectional view showing the power distribution components shown in Figure 12, and corresponds to Figure 4. Figure 14 is a cross-sectional view taken along line XIV-XIV of Figure 13. Figure 15 is a longitudinal cross-sectional view showing power distribution components according to yet another embodiment, and corresponds to Figure 13.

[0010] <Description of Embodiments of the Disclosure> First, embodiments of the Disclosure will be listed and described. The power distribution component of the Disclosure includes (1) a busbar, a resin case having a busbar holding portion for holding the busbar, an elastic arm portion held on the peripheral wall of the busbar holding portion and allowing elastic deformation toward the outer circumference of the busbar holding portion, and a locking claw provided on the elastic arm portion and positioned to overlap the busbar held on the busbar holding portion when the elastic arm portion is stationary, wherein the elastic arm portion extends in the circumferential direction of the peripheral wall.

[0011] According to the power distribution component of this disclosure, the elastic arm portion, which is allowed to elastically deform toward the outer circumference of the busbar holder, extends in the circumferential direction of the peripheral wall, and the arm length of the elastic arm portion, which is required to secure the amount of deflection of the elastic arm portion, can be secured in the circumferential direction of the peripheral wall of the busbar holder. As a result, it is not necessary to secure the arm length of the elastic arm portion in the height direction of the peripheral wall, as in conventional structures, and thus it is possible to reduce the height of the power distribution component compared to conventional structures. The power distribution component of this disclosure is mounted on in-vehicle equipment, etc., and includes structures in which a single busbar holder portion is provided in a resin case to hold a single busbar, and structures in which a plurality of busbar holder portions are provided in a resin case to hold a busbar, each holding a busbar.

[0012] (2) Preferably, in (1) above, a deformation restricting wall is further provided on the outer circumference of the elastic arm, and the elastic arm is positioned opposite the deformation restricting wall with a deformation-permissible gap between them. Since the elastic arm is positioned opposite the deformation restricting wall with a deformation-permissible gap between them, it is possible to restrict excessive elastic deformation of the elastic arm by contact of the elastic arm with the deformation restricting wall, while allowing the necessary deformation of the elastic arm toward the outer circumference. Furthermore, since the deformation restricting wall is positioned on the outer circumference of the elastic arm, buffering between the elastic arm and other members can be suppressed, thereby ensuring the durability of the elastic arm and suppressing damage.

[0013] (3) In (1) or (2) above, it is preferable that the elastic arm portion is connected to the circumferential wall at both ends in the circumferential direction, and that the locking claw is provided in the intermediate portion of the elastic arm portion in the circumferential direction. Since the locking claw provided in the intermediate portion of the elastic arm portion in the circumferential direction can be held by the elastic arm portion extending on both sides in the circumferential direction, the durability of the elastic arm portion can be improved.

[0014] (4) In any one of (1) to (3) above, it is preferable that the elastic arm portion has a curved portion that protrudes outward in the intermediate portion in the circumferential direction. By providing a curved portion that protrudes outward in the intermediate portion in the circumferential direction (longitudinal direction) of the elastic arm portion, it is possible to further secure the amount of deflection of the elastic arm portion toward the outer circumference without increasing the height dimension of the elastic arm portion or the resin case. This makes it possible to achieve both securing a further amount of deflection of the elastic arm portion toward the outer circumference and reducing the height of the power distribution components.

[0015] (5) In any one of (1) to (4) above, it is preferable that the elastic arm portion has a notched window that penetrates in the plate thickness direction on the base end side connected to the peripheral wall. By providing a notched window on the base end side of the elastic arm portion, the entire elastic arm portion becomes more susceptible to twist deformation, and the insertion force when inserting the busbar into the busbar holding portion can be reduced.

[0016] (6) In any one of (1) to (2) above and (4) when relating to (1) or (2), it is preferable that the elastic arm portion has a cantilevered shape connected to the circumferential wall at one end in the circumferential direction, and the locking claw is provided on the other end of the elastic arm portion in the circumferential direction. Because the elastic arm portion has a cantilevered shape that extends in the circumferential direction with one end held by the circumferential wall, elastic deformation toward the outer circumference of the elastic arm portion becomes even easier. Moreover, because the elastic arm portion extends in the circumferential direction, the amount of deflection of the elastic arm portion can be secured without increasing the height dimension of the elastic arm portion or the resin case.

[0017] (7) In any one of (1) to (6) above, it is preferable that the busbar holding portion has a support wall that supports the busbar, the busbar has a supported portion whose lower surface is placed on the support wall and supported, and an engaged portion that is located below the supported portion and protrudes parallel to the supported portion from a protruding end of a stepped portion formed by bending the end of the supported portion toward the lower surface, and the locking claw of the elastic arm portion is superimposed on the upper surface of the engaged portion. The busbar has an engaged portion that is located below the supported portion supported by the support wall of the busbar holding portion via a stepped portion, and the locking claw of the elastic arm portion is superimposed on the upper surface of the engaged portion. This makes it possible to use the stepped portion of the busbar to provide an engagement structure between the locking claw of the elastic arm portion and the engaged portion of the busbar in the space below the busbar holding portion, and to provide the elastic arm portion while further suppressing an increase in the height dimension of the peripheral wall of the busbar holding portion and the resin case.

[0018] (8) In (7) above, it is preferable that the upper end surface of the elastic arm portion does not protrude upward from the upper surface of the supported portion of the busbar. This makes it possible to provide the elastic arm portion at a height that does not exceed the busbar held by the busbar holding portion, and by cleverly utilizing the space created by the stepped portion of the busbar, it is possible to further reduce the height of the power distribution components.

[0019] (9) In (7) or (8) above, it is preferable that the upper surface of the supported portion of the busbar constitutes a heat dissipation surface, and that a heat conductive member is superimposed on the heat dissipation surface, and that the heat conductive member is capable of thermally contacting an external heat dissipation object. In (7) or (8) above, the busbar is configured in a stepped shape in order to provide a locking claw of an elastic arm portion that overlaps the busbar while reducing the height of the power distribution components. In this embodiment, by cleverly utilizing the stepped shape of the busbar, the upper surface of the supported portion positioned above the engaged portion of the busbar can be used as a heat dissipation surface, and a heat dissipation path from the busbar to the heat dissipation object can be secured by thermally contacting the external heat dissipation object via a heat conductive member superimposed on the heat dissipation surface. In other words, by configuring the busbar in a stepped shape, in addition to reducing the height of the power distribution components, it is possible to simultaneously achieve improved heat dissipation performance and absorption of dimensional tolerances by utilizing the stepped shape. Furthermore, since the upper surface of the supported portion of the busbar, which is used as a heat dissipation surface where the heat conductive members are superimposed, is located above the peripheral wall compared to the engaged portion of the busbar, the thickness of the heat conductive members required to contact the heat dissipation surface can be reduced, thereby reducing costs and improving heat dissipation performance.

[0020] (10) In (9) above, it is preferable that the heat dissipation surface is flush with the upper surface of the peripheral wall. Since the heat dissipation surface is flush with the upper surface of the peripheral wall, the thickness dimension of the heat conductive member can be further reduced to an advantage, thereby further cost reduction and improvement of heat dissipation performance. Note that the heat dissipation surface and the upper surface of the peripheral wall do not need to be strictly flush, and their height positions may differ within a range in which they are substantially flush.

[0021] (11) In the above (10), it is preferable that the heat conductive member is in the form of a sheet, the sheet-like heat conductive member has a peripheral edge and a central region surrounded by the peripheral edge, the central region is in close contact with the heat dissipation surface, and a chamfered portion is provided on the inner peripheral edge of the upper surface of the peripheral wall. The above configuration (10) makes it possible to use a sheet-like heat conductive member, and by bringing the central region of the sheet-like heat conductive member into close contact with the heat dissipation surface, the heat dissipation performance can be further improved. Moreover, the chamfered portion provided on the inner peripheral edge of the upper surface of the peripheral wall can guide the central region of the sheet-like heat conductive member toward the heat dissipation surface, and the central region of the heat conductive member can be stably brought into close contact with the heat dissipation surface.

[0022] <Details of Embodiments of the Disclosure> Specific examples of the power distribution components of the Disclosure will be described below with reference to the drawings. However, the Disclosure is not limited to these examples and is intended to include all modifications within the meaning and scope of the Claims as shown in the Claims.

[0023] <Embodiment 1> Hereinafter, a power distribution component 10 according to Embodiment 1 of the present disclosure will be described with reference to Figures 1 to 5. This power distribution component 10 constitutes a wiring module used in a battery pack (not shown) installed in, for example, an electric vehicle or a hybrid vehicle. The power distribution component 10 has a structure in which a plurality of busbar holding parts 14 are provided on a resin case 12 made of synthetic resin, and a busbar 16 that electrically connects the electrode terminals of adjacent single cells housed in a battery pack (not shown) is housed and held in each busbar holding part 14. In Figures 1 to 5, a single busbar holding part 14 provided on the resin case 12 of the power distribution component 10 is shown separately. In Figure 1, the parts of the resin case 12 other than the single busbar holding part 14 are shown by dashed lines.

[0024] As shown in Figure 1, the busbar holder 14 is integrally provided in a resin case 12 made of synthetic resin. The busbar holder 14 has a peripheral wall 18 that extends in a substantially rectangular frame shape in plan view. In Figure 2, it comprises a pair of long wall sections 20a and 20b that extend in the vertical direction, and a pair of short wall sections 22a and 22b that extend in the left-right direction and connect the upper and lower ends of the pair of long wall sections 20a and 20b, respectively. In Figure 2, the short wall section 22a positioned above is divided in the middle portion of its extension direction, which is in the circumferential direction of the busbar holder 14, and a pair of divided sections 24a and 24b are arranged opposite each other with a gap in between in the extension direction of the short wall section 22a.

[0025] Between the pair of subsections 24a and 24b of the short wall portion 22a, an elastic arm portion 26 is provided, extending in the direction of extension of the short wall portion 22a, which is in the circumferential direction of the busbar holding portion 14. The elastic arm portion 26 is made of the same resin material as the circumferential wall 18 and has a strip shape with a height dimension slightly smaller than that of the circumferential wall 18 (short wall portion 22a). The elastic arm portion 26 extends in the circumferential direction of the busbar holding portion 14 and connects the pair of subsections 24a and 24b. That is, both ends of the elastic arm portion 26 in the direction of extension are connected to and fixed to the pair of subsections 24a and 24b. In the central part of the elastic arm portion 26 in the direction of extension, a locking claw 28 is provided, projecting toward the busbar 16 from the inner surface facing the busbar 16. The locking claw 28 is positioned overlapping the busbar 16, which is held by the busbar holding portion 14, from the upper side in the thickness direction of the busbar 16, when the elastic arm portion 26 is in a stationary state, i.e., in a non-deformed state where the elastic arm portion 26 is not elastically deformed. The upper end surface of the locking claw 28 is provided with a downward sloping guide taper 30 that protrudes toward the busbar 16 toward the lower end. As a result, when the busbar 16 is mounted in the busbar holding portion 14, the busbar 16 that comes into contact with the guide taper 30 of the locking claw 28 from above can move smoothly toward the inside of the busbar holding portion 14 with a low insertion force, thereby reducing the insertion force of the busbar 16. In addition, the pressing force of the busbar 16 toward the guide taper 30 can favorably cause elastic deformation of the elastic arm portion 26 toward the outer circumference of the busbar holding portion 14.

[0026] Between the ends of the elastic arm portion 26 in the extending direction and the locking claw 28 provided in the central portion, curved portions 32 are provided that protrude outward (upward in Figure 2) from the outer circumference of the busbar holding portion 14. On both sides of the locking claw 28 provided in the central portion of the elastic arm portion 26 in the extending direction, curved portions 32 protruding outward are provided in the region leading to the ends of the elastic arm portion 26 connected to a pair of subsections 24a and 24b. As a result, the amount of deflection of the elastic arm portion 26 can be advantageously secured without increasing the height dimension of the resin case 12.

[0027] On the outer circumference side of the elastic arm portion 26 (upper side in Figure 2), which is the outer circumference side of the busbar holding portion 14, a deformation restricting wall 34 is positioned opposite with a predetermined gap in between. The deformation restricting wall 34 has the same height dimension as the short wall portion 22a that constitutes the circumferential wall 18, and has a length dimension that faces the elastic arm portion 26 over its entire length in the longitudinal direction, which is the extension direction. The longitudinal ends of the deformation restricting wall 34 are connected to a pair of subsections 24a and 24b of the short wall portion 22a and are integrated with the circumferential wall 18 (short wall portion 22a) via a pair of connecting walls 36, 36 that protrude outward (upper side in Figure 2). As a result, the elastic arm portion 26 and the deformation restricting wall 34 are positioned opposite each other with a deformation-permissible gap 38 separated by the deformation restricting wall 34 and the pair of connecting walls 36, 36. This deformation-tolerant gap 38 allows for elastic deformation of the elastic arm portion 26 toward the outer circumference (upper side in Figure 2) of the busbar holding portion 14.

[0028] As shown in Figures 3-4, the busbar holding section 14 has a support wall 40 that is integrally connected between the long wall sections 20a and 20b and has a rectangular frame shape in plan view. The upper surface of the support wall 40 is positioned slightly lower than the upper surfaces of the long wall sections 20a and 20b and the short wall sections 22a and 22b that constitute the peripheral wall 18, as well as the deformation restricting wall 34. The height of the upper surface of the support wall 40 is set so that when the supported portion 50 of the busbar 16, which will be described later, is placed on the upper surface of the support wall 40, the supported portion 50 of the busbar 16 does not exceed the peripheral wall 18. In addition, the electrode terminals of a single cell housed in a battery pack (not shown) on which the power distribution components 10 are placed may be inserted through a through hole 42 that penetrates the central part of the support wall 40 and connected to the busbar 16. Alternatively, the positive and negative terminals of adjacent single cells may be superimposed from below on the first engaging portion 56 and the second engaging portion 58 of the busbar 16, which will be described later, so that adjacent single cells are electrically connected to each other by the busbar 16. Note that the method of fixing these single cell electrode terminals to the busbar 16 is not limited. Furthermore, by providing a through hole 42 in the central part of the support wall 40, the weight of the busbar holding portion 14 (peripheral wall 18) may be reduced and the heat dissipation performance against heat generated due to current flow between the single cell and the busbar 16 may be improved.

[0029] The busbar holder 14 has a pair of locking projections 44 protruding from the inner surface of the short wall portion 22b, and is designed to overlap the upper surface of the second engaged portion 58 of the busbar 16, which will be described later, placed on the busbar mounting portion 46 that protrudes inward from the long wall portions 20a and 20b, respectively. As a result, the second engaged portion 58 of the busbar 16, which will be described later, is held between the locking projections 44 and the busbar mounting portion 46 at one end of the busbar holder 14 (the short wall portion 22b side).

[0030] The busbar 16, held by the busbar holding portion 14 having the structure described above, is formed by press-forming a metal plate such as copper, copper alloy, aluminum, or aluminum alloy. As shown in Figures 3 to 4, the busbar 16 has a flat supported portion 50 provided in the central part in the longitudinal direction, a first stepped portion 52 and a second stepped portion 54 formed by bending both ends of the supported portion 50 toward the lower surface of the supported portion 50, and a first engaged portion 56 and a second engaged portion 58 that protrude parallel to the supported portion 50 from the respective protruding ends of the first stepped portion 52 and the second stepped portion 54, respectively, and are located below the supported portion 50. In this embodiment, the protruding dimension of the first stepped portion 52 is larger than that of the second stepped portion 54, and the first engaged portion 56 is positioned below the second engaged portion 58.

[0031] The busbar 16, having this structure, is assembled and held in the busbar holding portion 14 provided in the resin case 12 as follows. First, the tip end of the second engaged portion 58 of the busbar 16 is placed on the busbar mounting portion 46 and inserted between the locking projection 44 and the busbar mounting portion 46. Then, the first engaged portion 56 of the busbar 16 is brought closer to the elastic arm portion 26 and the tip end of the first engaged portion 56 is brought into contact with the guiding taper 30 of the locking claw 28 and pressed downward. The pressing force applied to the first engaged portion 56 is transmitted to the locking claw 28, and the elastic arm portion 26 is elastically deformed toward the deformation restricting wall 34, which is on the outer circumference side of the busbar holding portion 14, thereby enabling the busbar 16 to be inserted inward into the busbar mounting portion 46. Then, as shown in Figure 5, when the elastic arm portion 26 elastically deforms until the locking claw 28 is positioned on the outer circumference side of the first engaged portion 56, the locking claw 28 overcomes the first engaged portion 56, and the elastic arm portion 26 elastically returns to its stationary position before elastic deformation. As a result, as shown in Figure 4, the busbar 16 is held by the busbar holding portion 14 with the lower surface of the supported portion 50 of the busbar 16 resting on the support wall 40. In this state, the locking claw 28 of the elastic arm portion 26, which has elastically returned to its stationary position, is superimposed on the upper surface of the first engaged portion 56 of the busbar 16. As a result, the displacement of the busbar 16 in the front-rear and left-right directions is restricted by the busbar 16 contacting the peripheral wall 18 and the first stepped portion 52 / second stepped portion 54 contacting the support wall 40, while upward displacement of the busbar 16 is prevented by the first engaged portion 56 contacting the locking claw 28 and the second engaged portion 58 contacting the locking projection 44.

[0032] In the power distribution component 10 having the structure described above, the elastic arm portion 26, which is allowed to elastically deform toward the outer circumference of the busbar holding portion 14, extends in the direction of extension of the short wall portion 22a which is in the circumferential direction of the peripheral wall 18 of the busbar holding portion 14. The arm length of the elastic arm portion 26, which is necessary to secure the required amount of deflection of the elastic arm portion 26, can be secured in the circumferential direction of the peripheral wall 18 of the busbar holding portion 14. As a result, it is not necessary to secure the arm length of the elastic arm portion in the height direction of the peripheral wall, as in the conventional structure, and therefore it is possible to reduce the height of the power distribution component 10 compared to the conventional structure.

[0033] Furthermore, since the deformation-restricting wall 34 is positioned opposite the elastic arm portion 26 on its outer circumference, separated by a deformation-allowable gap 38, it is possible to restrict excessive elastic deformation of the elastic arm portion 26 by its contact with the deformation-restricting wall 34, while allowing the necessary deformation of the elastic arm portion 26 toward its outer circumference. In particular, since the deformation-allowable gap 38 is demarcated by the deformation-restricting wall 34 surrounding the outer surface of the elastic arm portion 26 and a pair of connecting walls 36 protruding from both ends of it, it is possible to suppress buffering between the elastic arm portion 26 and other members, thereby ensuring the durability of the elastic arm portion 26 and suppressing damage.

[0034] Furthermore, the elastic arm portion 26 can hold the locking claws 28, which are provided in the circumferential middle portion of the elastic arm portion 26, at both sides of the elastic arm portion 26, which extend circumferentially on both sides and are connected to the opposing cross-sections 24a and 24b of the short wall portion 22a. This further improves the durability of the elastic arm portion 26. In addition, on both sides of the circumferential (longitudinal) portion of the locking claws 28 of the elastic arm portion 26, curved portions 32 that protrude outward are provided in the longitudinal middle portion. This allows for further securing of the amount of deflection of the elastic arm portion 26 outward without increasing the height dimensions of the elastic arm portion 26 or the resin case 12, thereby achieving both securing the amount of deflection of the elastic arm portion 26 and reducing the height of the power distribution component 10.

[0035] In addition, the busbar 16 has a first engaged portion 56 and a second engaged portion 58 that are positioned below the supported portion 50 supported by the support wall 40 of the busbar holding portion 14 via a first stepped portion 52 and a second stepped portion 54, and the locking claw 28 and locking projection 44 of the elastic arm portion are superimposed on the upper surfaces of the first engaged portion 56 and the second engaged portion 58. As a result, the engagement structure between the locking claw 28 of the elastic arm portion 26 and the first engaged portion 56 of the busbar 16, and the engagement structure between the locking projection 44 and the second engaged portion 58 can be provided in the space below the busbar holding portion 14 by utilizing the first stepped portion 52 and the second stepped portion 54 of the busbar 16. As a result, a busbar holding structure using the elastic arm portion 26 and the locking projection 44 can be provided while further suppressing the increase in the height dimension of the peripheral wall 18 of the busbar holding portion 14 and the resin case 12. In particular, in this embodiment, the elastic arm portion 26 can be provided with a height dimension that does not exceed the busbar 16 held by the busbar holding portion 14, and by cleverly utilizing the space created by the first stepped portion 52 of the busbar 16, it is possible to further reduce the height of the power distribution component 10 equipped with the elastic arm portion 26.

[0036] <Modifications> Although Embodiment 1 has been described in detail above as a specific example of the present disclosure, the present disclosure is not limited by this specific description. Modifications, improvements, etc., to the extent that they can achieve the purpose of the present disclosure are included in the present disclosure. For example, the following modifications of the embodiments are also included in the technical scope of the present disclosure.

[0037] (1) In the embodiment 1 described above, both ends of the elastic arm portion 26 were connected to a pair of subsections 24a and 24b of the short wall portion 22a while maintaining the same cross-sectional area as the other parts of the elastic arm portion 26, but the invention is not limited to this. For example, as shown in an enlarged view in Figure 6, the elastic arm portion 26 may have a notched window 60 penetrating in the thickness direction on the base end side connected to the peripheral wall 18 (subsections 24a and 24b). By providing a notched window 60 on the base end side of the elastic arm portion 26, the entire elastic arm portion 26 becomes more susceptible to twist deformation, thereby reducing the insertion force required when inserting the busbar 16 into the busbar holding portion 14.

[0038] (2) In the embodiment 1 described above, the elastic arm portion 26 was connected to the peripheral wall 18 at both ends in the circumferential direction, but is not limited to this. For example, as shown in the modified example (2) elastic arm portion 62 shown in an enlarged view in Figure 7, the elastic arm portion 62 has a cantilevered shape connected to the peripheral wall 18 (short wall portion 22a) at one end in the circumferential direction, and a locking claw 28 may be provided at the other end in the circumferential direction of the elastic arm portion 62. Since the elastic arm portion 62 has a cantilevered shape with one end held by the peripheral wall 18 and extending in the circumferential direction, elastic deformation toward the outer circumference of the elastic arm portion 62 becomes even easier. Moreover, since the elastic arm portion 62 extends in the circumferential direction, the amount of deflection of the elastic arm portion 62 can be secured without increasing the height dimension of the elastic arm portion 62 or the resin case 12, which is the same as in embodiment 1.

[0039] (3) In the embodiment 1 described above, the elastic arm portion 26 was provided with a curved portion 32 that protruded outward in the area where the locking claw 28 was not provided, but it is not limited to this. For example, as shown in the modified example (3) elastic arm portion 64 shown in an enlarged view in Figure 8, if the required amount of deflection can be secured in the elastic arm portion 64, the elastic arm portion 64 may extend straight in the direction of extension of the short wall portion 22a which is in the circumferential direction of the peripheral wall 18, without providing the curved portion 32.

[0040] (4) In the embodiment 1 described above, the second engaged portion 58 of the busbar 16 engaged with a locking projection 44 provided on the short wall portion 22b of the busbar holding portion 14 to prevent upward displacement, but the invention is not limited to this. For example, as shown in modified example (4) in Figure 9, an elastic arm portion 68 may also be provided on the short wall portion 22b side, dividing the central portion and connecting the pair of divided sections 66a, 66b, and a locking claw 28 protruding from the elastic arm portion 68 may be brought into contact with the second engaged portion 58 of the busbar 16 to prevent upward displacement of the busbar 16. The elastic arm portion may be provided at any position on the peripheral wall 18, and instead of or in addition to the elastic arm portions 26, 68 in Figure 9, an elastic arm portion may be provided on at least one of the long wall portions 20a, 20b. Furthermore, a displacement restricting wall that restricts the displacement of the elastic arm portion, such as the elastic arm portion 68, may not be provided.

[0041] (5) In the first embodiment, a first engaged portion 56 and a second engaged portion 58 were provided on both sides of the supported portion 50 of the busbar 16. However, the shape of the busbar 16 can be any shape depending on its relationship with other members. For example, as shown in Figure 10, the busbar 16 may be a flat plate shape without any stepped portions. Even in such a case, by simply displacing the position of the bottom surface of the locking claw 28 on the elastic arm portions 26 and 68 upward compared to the first embodiment, the locking claw 28 can be engaged with the busbar 16 without stepped portions, and the effect of reducing the height of the power distribution components 10, similar to the first embodiment, can be enjoyed.

[0042] (6) Next, a power distribution component 70 according to another embodiment of the present disclosure will be described with reference to Figure 11. The basic structure of the power distribution component 70 according to this embodiment is the same as that of the power distribution component 10 of Embodiment 1, so the bus bar 16 and the bus bar holding portion 14 (peripheral wall 18) will be omitted from the description. In the power distribution component 70 according to this embodiment, the upper surface of the supported portion 50 of the bus bar 16 constitutes a heat dissipation surface 72, and a heat conductive sheet 74 as a heat conductive member is superimposed on this heat dissipation surface 72. Specifically, the heat dissipation surface 72 formed by the upper surface of the supported portion 50 is substantially flush with the upper surface of the peripheral wall 18, and the heat conductive sheet 74 is formed to cover the entire upper surface of the peripheral wall 18, so that when the heat conductive sheet 74 is placed on the upper surface of the peripheral wall 18 it is also superimposed on the upper surface of the supported portion 50 (heat dissipation surface 72). Furthermore, the thermal conductive sheet 74 can make thermal contact with the metal housing 76 of the battery pack, which is an external heat dissipation target. This allows the heat generated by the current flow between the electrode terminals of the single cell and the busbar 16 to be dissipated from the metal housing 76 through the heat dissipation surface 72 of the busbar 16 and the thermal conductive sheet 74. As a result, in addition to the same effects as in Embodiment 1, a power distribution component 70 with good heat dissipation performance can be provided.

[0043] Furthermore, any known material having excellent thermal conductivity can be used as the heat conductive member, and it is preferable that it be in the form of a sheet as in this embodiment, and may be formed from, for example, metal or synthetic resin. In particular, it is preferable that the heat conductive member (heat conductive sheet 74) has a certain degree of elasticity. The elasticity of the heat conductive sheet 74 allows it to be positioned in a compressed state between the supported portion 50 (heat dissipation surface 72) and the metal housing 76 in the vertical direction, and the heat conductive sheet 74 can be brought into close contact with the overlapping surfaces of the heat dissipation surface 72 and the metal housing 76. In particular, if the heat conductive sheet 74 has elasticity, even if there is a slight difference in height between the upper surface of the supported portion 50 (heat dissipation surface 72) and the upper surface of the peripheral wall 18, the heat conductive sheet 74 can be stably overlapped with the heat dissipation surface 72 and the upper surface of the peripheral wall 18, respectively. Therefore, in this embodiment, the heat dissipation surface 72 and the upper surface of the peripheral wall 18 do not need to be strictly flush, and a certain degree of height misalignment is permissible.

[0044] (7) Next, the power distribution component 80 according to another aspect of the present disclosure will be described with reference to FIGS. 12 to 14. In this aspect, as described above, the height positions of the heat dissipation surface 72 and the upper surface of the peripheral wall 18 are slightly different. Particularly in this aspect, the heat dissipation surface 72 is located slightly below the upper surface of the peripheral wall 18. Also in this aspect, the heat conduction member is constituted by a sheet-like heat conduction sheet 82. Particularly in this aspect, when the heat conduction sheet 82 is pressed against the bus bar holding portion 14 (peripheral wall 18), as shown in FIGS. 13 and 14, the heat conduction sheet 82 has a peripheral edge portion 84 that is pressed against the long wall portions 20a, 20b and the short wall portions 22a, 22b at the outer peripheral portion, and a central region 86 that is surrounded by the peripheral edge portion 84 at the central portion and is not pressed against the long wall portions 20a, 20b and the short wall portions 22a, 22b. This central region 86 is substantially rectangular in plan view. When the heat conduction sheet 82 is pressed against the bus bar holding portion 14 (peripheral wall 18), the central region 86 protrudes slightly downward on the bus bar 16 side compared to the peripheral edge portion 84. On the other hand, in this aspect, in each of the long wall portions 20a, 20b constituting the peripheral wall 18, a chamfered portion 88 is provided on the inner peripheral edge of the upper surface over substantially the entire length in the length direction. These chamfered portions 88 are formed so as to incline downward as they go inward in the facing direction of the long wall portions 20a, 20b. Even in the bus bar holding portion 14 (peripheral wall 18) having such a shape, similar to the aspect shown in FIG. 11 above, the central region 86 constituted by the central portion of the heat conduction sheet 82 is overlapped and closely contacted with the heat dissipation surface 72 which is the upper surface of the supported portion 50 in the bus bar 16. Particularly, since the chamfered portions 88 that guide inward in the facing direction of each of the long wall portions 20a, 20b are formed, by pressing the heat conduction sheet 82 against the bus bar holding portion 14 (peripheral wall 18), the central region 86 is stably formed in the heat conduction sheet 82, and the central region 86 in the heat conduction sheet 82 and the upper surface (heat dissipation surface 72) of the supported portion 50 can be stably contacted.

[0045] In the embodiments shown in Figures 12 to 14 above, the heat dissipation surface 72 is located slightly below the upper surface of the peripheral wall 18, and the central region 86 that protrudes downward is in close contact with the heat dissipation surface 72. However, for example, as in the power distribution component 90 shown in Figure 15, by setting the height of the heat dissipation surface 72 slightly above the upper surface of the peripheral wall 18, the heat conductive sheet 82 is composed of a central region 86 that is created by being pressed against the heat dissipation surface 72 and a peripheral portion 84 that is not pressed against the heat dissipation surface 72, and this also allows the central region 86 and the heat dissipation surface 72 to be stably in close contact.

[0046] 10 Power distribution component (Embodiment 1) 12 Resin case 14 Busbar holding part 16 Busbar 18 Peripheral wall 20a, 20b Long wall part 22a, 22b Short wall part 24a, 24b Sectional cross-section 26 Elastic arm part 28 Locking claw 30 Enticing taper 32 Curved part 34 Deformation restricting wall 36 Connecting wall 38 Deformation allowable gap 40 Support wall 42 Through hole 44 Locking projection 46 Busbar mounting part 50 Supported part 52 First stepped part 54 Second stepped part 56 First engaged part 58 Second engaged part 60 Notched window 62 Elastic arm part (cantilevered beam) 64 Elastic arm part (without curved part) 66a, 66b Sectional cross-section 68 Elastic arm part (second) 70 Power distribution component (Figure 11) 72 Heat dissipation surface 74 Thermal conductive sheet (thermal conductive material) 76 Metal housing (of battery pack) (heat dissipation target) 80 Power distribution component (Figures 12-14) 82 Thermal conductive sheet (thermal conductive material) 84 Peripheral area 86 Central area 88 Chamfered area 90 Power distribution component (Figure 15)

Claims

1. A power distribution component comprising: a busbar; a resin case having a busbar holding portion for holding the busbar; an elastic arm portion held by the peripheral wall of the busbar holding portion and allowing elastic deformation toward the outer circumference of the busbar holding portion; and a locking claw provided on the elastic arm portion and positioned to overlap the busbar held by the busbar holding portion when the elastic arm portion is stationary, wherein the elastic arm portion extends in the circumferential direction of the peripheral wall.

2. The power distribution component according to claim 1, further comprising a deformation-restricting wall disposed on the outer circumference of the elastic arm portion, wherein the elastic arm portion is disposed opposite the deformation-restricting wall with a deformation-allowable gap between them.

3. The power distribution component according to claim 1 or claim 2, wherein the elastic arm portion is connected to the circumferential wall at both ends in the circumferential direction, and the locking claw is provided in the intermediate portion of the elastic arm portion in the circumferential direction.

4. The power distribution component according to claim 1 or 2, wherein the elastic arm portion has a curved portion that protrudes toward the outer circumference in the intermediate portion in the circumferential direction.

5. The power distribution component according to claim 1 or 2, wherein the elastic arm portion has a notched window that penetrates in the thickness direction at the base end side connected to the peripheral wall.

6. The power distribution component according to claim 1 or 2, wherein the elastic arm portion has a cantilevered shape connected to the circumferential wall at one end in the circumferential direction, and the locking claw is provided at the other end of the elastic arm portion in the circumferential direction.

7. The power distribution component according to claim 1 or 2, wherein the busbar holding portion has a support wall for supporting the busbar, the busbar has a supported portion whose lower surface rests on the support wall and is supported, and an engaged portion that protrudes parallel to the supported portion from a protruding end of a stepped portion formed by bending the end of the supported portion toward the lower surface, and the locking claw of the elastic arm portion is superimposed on the upper surface of the engaged portion.

8. The power distribution component according to claim 7, wherein the upper end surface of the elastic arm portion does not protrude upward from the upper surface of the supported portion of the busbar.

9. The power distribution component according to claim 7, wherein the upper surface of the supported portion of the busbar constitutes a heat dissipation surface, and a heat conductive member is superimposed on the heat dissipation surface, and the heat conductive member is capable of thermal contact with an external heat dissipation object.

10. The power distribution component according to claim 9, wherein the heat dissipation surface is flush with the upper surface of the peripheral wall.

11. The power distribution component according to claim 10, wherein the heat conductive member is in the form of a sheet, the sheet-like heat conductive member has a peripheral edge and a central region surrounded by the peripheral edge, the central region is in close contact with the heat dissipation surface, and a chamfered portion is provided on the inner peripheral edge of the upper surface of the peripheral wall.

Images