Busbar module

Abstract

This invention provides a busbar module that allows for miniaturization and weight reduction of the insulating cover that covers the surface side of the busbar. [Solution] One embodiment of the busbar module comprises a busbar 11, a busbar case 20 made of insulating resin, and an insulating cover 30. The busbar 11 has a pair of connection seats 12 and conductive pieces 13. The busbar case 20 has an opening 23. The opening 23 exposes each connection seat 12 to the surface side. The busbar case 20 houses the busbar 11. The insulating cover 30 is detachably attached to the busbar case 20. The insulating cover 30 covers the surface side of the busbar 11. The busbar case 20 includes a shielding wall 26 that shields the surface side of the conductive pieces 13. A locking piece 27 that engages with the conductive pieces 13 of the busbar 11 is arranged on the back side of the shielding wall 26.

Description

Technical Field

[0001] Embodiments of the present invention relate to a bus bar module.

Background Art

[0002] In vehicles such as electric vehicles and hybrid cars, a battery pack (assembled battery) is used as the power source for a drive motor. The battery pack is configured by assembling a plurality of battery cells. The plurality of battery cells are, for example, connected in series by a bus bar with electrodes of adjacent battery cells. When a bus bar is used in a battery pack or the like, each bus bar is housed in a bus bar case made of an insulating resin and used as a bus bar module (see, for example, Patent Document 1).

[0003] The bus bar module described in Patent Document 1 has a bus bar housed in a bus bar case, and the surface side (opposite side to the battery pack) of the bus bar housing portion of the bus bar case is covered with a detachable insulating cover. The bus bar has a pair of connection seat portions connected to the electrodes (terminals) of the battery cells, and a conduction piece portion that conducts the pair of connection seat portions. The bus bar case is provided with a bus bar housing portion capable of housing the bus bar from the surface side, and an opening (through hole) in which a pair of connection seat portions of the bus bar are arranged. Each connection seat portion arranged in the opening is engaged with the corresponding electrode of the battery cell and connected to the corresponding electrode by fastening with a nut or the like. Further, the bus bar housed in the bus bar housing portion is prevented from coming off by a locking claw or the like provided on the bus bar case.

[0004] In the state where the bus bar is assembled in the bus bar housing portion, the surface side of the bus bar housing portion of the bus bar case is covered with an insulating cover. At this time, the insulating cover can maintain the bus bar in an insulated state with respect to the outside by covering the surface sides of the pair of connection seat portions and the conduction piece portion of the bus bar.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2014-229594 [Overview of the project] [Problems that the invention aims to solve]

[0006] The busbar module described in Patent Document 1 has a structure in which, after assembling the busbar into the busbar case, the surface sides of the connection seat portion and conductive piece portion of the busbar are covered with an insulating cover. However, when the conductive terminal portion of the busbar extends in a roughly U-shape away from the pair of connection seat portions, the insulating cover becomes larger along with the overall size of the busbar. And when the insulating cover becomes larger, the entire busbar module becomes larger, and the total weight of the busbar module also increases.

[0007] One embodiment of the present invention provides a busbar module that can achieve miniaturization and weight reduction of the insulating cover that covers the surface side of the busbar. [Means for solving the problem]

[0008] A busbar module according to one embodiment of the present invention comprises a busbar having a pair of connection seats connected to corresponding terminals of an object to be mounted, and a conductive piece that connects the pair of connection seats; an insulating resin busbar case that houses the busbar and has an opening that exposes each of the connection seats to the surface side opposite to the object to be mounted; and an insulating cover that is detachably attached to the busbar case and covers the surface side of the busbar, wherein the busbar case has a shielding wall that shields the surface side of the conductive piece, and a locking piece that locks the conductive piece of the busbar is arranged on the back side of the shielding wall, which is on the same side as the object to be mounted. [Effects of the Invention]

[0009] According to a busbar module of one embodiment of the present invention, the insulating cover that covers the surface side of the busbar can be made smaller and lighter. [Brief explanation of the drawing]

[0010] [Figure 1] This is a plan view of the busbar module of the embodiment. [Figure 2] This is a rear view of the busbar module of the embodiment. [Figure 3] This is an enlarged plan view of a portion of Figure 1 showing the busbar module of the embodiment. [Figure 4] This is a perspective view of a portion of the busbar module of the embodiment, seen from the front side. [Figure 5] This is an enlarged rear view of a portion of Figure 2 of the busbar module of the embodiment. [Figure 6] This is a perspective view of a portion of the busbar module of the embodiment, seen from the back side. [Figure 7] This is a rear view of a portion of the busbar module of the embodiment. [Figure 8] This is a cross-sectional view of the busbar module of the embodiment along the line VIII-VIII in Figure 5. [Figure 9] This is an enlarged plan view of a portion of the busbar module of the embodiment. [Modes for carrying out the invention]

[0011] The busbar module 10 of this embodiment will be described below with reference to the drawings. In this disclosure, terms are defined as follows: “Connection” may include, but is not limited to, a mechanical connection; and “Connection” may include, but is not limited to, a case where two elements to be connected are directly connected; and may include a case where two elements to be connected are connected with another element in between.

[0012] Figure 1 is a plan view of the busbar module 10 of this embodiment. Figure 2 is a rear view of the busbar module 10. The busbar module 10 of this embodiment is mounted on a battery pack (battery assembly) not shown. The battery pack is composed of multiple battery cells stacked together in a substantially rectangular shape. A pair of columnar electrodes 1 (positive and negative electrodes) protrude from one surface perpendicular to the stacking direction of each battery cell. The multiple battery cells are arranged such that the positions of the positive and negative electrodes are reversed in adjacent battery cells. The electrodes 1 of the stacked battery cells are arranged linearly with the positive and negative electrodes alternating in the stacking direction. The rows of electrodes 1, with the positive and negative electrodes arranged alternately, are arranged in two rows in a plan view of the battery pack. In this embodiment, the battery pack constitutes the object to be mounted, and the electrodes 1 (positive and negative electrodes) of each battery cell constitute the terminals of the object to be mounted.

[0013] The busbar module 10 includes multiple busbars 11, 11A for connecting the electrodes 1 of multiple battery packs in series. The busbars 11, 11A are formed from conductive metal plates. As shown in Figure 1, the multiple busbars 11, 11A are arranged in two layers, upper and lower, in a plan view of the busbar module 10. Each busbar 11, 11A connects the positive and negative electrodes of battery cells that are adjacent to each other in the stacking direction (left and right direction in Figures 1 and 2). Due to the relationship between the multiple busbars 11, 11A and the battery cells in series, the busbars 11, 11A arranged in the upper layer and the busbars 11A arranged in the lower layer are offset from each other in the left and right direction in a plan view.

[0014] In the busbar module 10 of this embodiment, in the plan view shown in Figure 1, only the busbar 11 located in the center of the upper section has a different shape, while the other busbars 11A in the upper and lower sections have the same shape. The main components of the busbar module 10 of this embodiment are the busbar 11 located in the center of the upper section, the busbar case 20 which will be described later and houses the busbar 11, and the insulating cover 30 which will be described later and covers a part of the surface of the busbar 11. These main components will be described in detail below.

[0015] In addition, the other bus bars 11A in the upper and lower sections have a pair of connection seat portions 12A that are rectangular in plan view, and a conduction piece portion 13 that conducts the pair of connection seat portions 12A. The conduction piece portion 13 extends between the pair of connection seat portions 12A. The shape of each bus bar 11A when viewed in plan view, combining the pair of connection seat portions 12A and the conduction piece portion 13, is formed in a horizontally long rectangular shape as shown in FIG. 1.

[0016] FIG. 3 is an enlarged plan view of a part of the bus bar module 10 (the central upper part in FIG. 1), and FIG. 4 is a perspective view of the same part of the bus bar module 10 as viewed from the front side. Further, FIG. 5 is an enlarged rear view of a part of the bus bar module 10 (the central upper part in FIG. 2), and FIG. 6 is a perspective view of the same part of the bus bar module 10 as viewed from the back side. The bus bar 11 in the central upper part has a pair of connection seat portions 12 that are rectangular in plan view, and a conduction piece portion 13 that conducts the pair of connection seat portions 12. The conduction piece portion 13 is formed in a substantially U shape in plan view. Both ends on the opening side of the substantially U shape of the conduction piece portion 13 are connected to one side (the lower side in FIGS. 3 to 6) on the same side of each connection seat portion 12. The substantially U-shaped conduction piece portion 13 extends in a direction intersecting the arrangement direction of the pair of connection seat portions 12. Through holes 14 (see FIGS. 5 and 6) into which the electrodes 1 of the corresponding battery cells are inserted are formed in each connection seat portion 12 of the bus bar 11.

[0017] The bus bar 11 in the central upper part is different from the other bus bars 11A in that the separation width between the pair of connection seat portions 12 is wider and that the shape of the conduction piece portion 13 in plan view is substantially U-shaped. In the state where the electrodes becomes inserted into the through holes 14 of the connection seat portions 12, 12A, nuts 15 are tightened on the ends of the electrodes 1. Each electrode 1 is electrically connected to the corresponding connection seat portions 12, 12A by being tightened by these nuts 15.

[0018] As shown in Figures 1 and 2, each busbar 11, 11A is housed in an insulating resin busbar case 20, 20A, and in this state, the side of the connection seat 12, 12A opposite to the side where the battery pack is placed is covered by an insulating cover 30. Each busbar case 20, 20A is connected to each other by a flexible connecting part 18. The busbar case 20A has a busbar housing section (not shown) that opens to the surface side, and the corresponding busbar 11A is housed in the busbar housing section from the surface side. The busbar 11A housed in the busbar housing section is locked to the busbar case 20A by a locking claw or the like (not shown).

[0019] In the following, the side of the busbar module 10 opposite to the side on which the battery pack (object to be mounted) is placed will be referred to as the "front side," and the side of the busbar module 10 on the same side as the side on which the battery pack (object to be mounted) is placed will be referred to as the "back side." The direction connecting the front side and the back side may also be referred to as the "front-back direction." Furthermore, for the sake of clarity in the following explanation, the upper part of Figures 1 to 6 will be referred to as "top," and the lower part of the figures will be referred to as "bottom." Also, the left-right direction in the figures will be referred to as the "left-right direction."

[0020] As shown in Figures 3 and 4, a pair of covering walls 22 are formed on the surface side of the busbar case 20, surrounding the periphery of the connection seat portion 12 of the busbar 11. Each covering wall 22 is formed in a substantially rectangular shape when viewed from above. The inside of each covering wall 22 penetrates in the front-to-back direction. This penetrating portion constitutes an opening 23 for exposing the connection seat portion 12 of the busbar 11 to the surface side.

[0021] Furthermore, as shown in Figures 3 to 6, a through-hole 24 is formed between the pair of covering walls 22, penetrating the busbar case 20 in the front-to-back direction. This through-hole 24 is formed in a roughly elliptical shape in plan view, elongated in the vertical direction. The through-hole 24 is surrounded by a peripheral wall 25 that stands upright in the front-to-back direction. A portion of the peripheral wall 25 is shared with portions of the left and right covering walls 22. The peripheral wall 25 comprises a portion 25s shared with the left and right covering walls 22, an upper edge portion 25u located above the left and right shared portion 25s, and a lower edge portion 25l located below the left and right shared portion 25s. The lower edge portion 25l bulges concavely downward in the figure compared to the left and right covering walls 22.

[0022] The through-holes 24 formed in the busbar case 20 are holes for exposing bolt fastening parts, equipment operating parts, etc., that protrude from the outer surface of the battery pack to which the busbar module 10 is attached. These through-holes 24 are large in size to allow operation of large bolts and equipment. The shape of the through-holes 24 is not limited to an elliptical shape.

[0023] A shielding wall 26 is provided on the lower side of the left and right covering walls 22 and peripheral wall 25 of the busbar case 20, extending in a direction substantially perpendicular to the upright direction of the covering walls 22 and peripheral wall 25. The substantially U-shaped conductive piece 13 of the busbar 11 is positioned on the back side of the shielding wall 26, along the shielding wall 26. When the busbar 11 is assembled to the busbar case 20, the shielding wall 26 shields the surface side of the conductive piece 13 of the busbar 11. The busbar case 20 is made of insulating resin. Therefore, the conductive piece 13 of the busbar 11 is electrically shielded on its surface side by the shielding wall 26.

[0024] Furthermore, as shown in Figures 5 and 6, a locking piece 27 is provided on the back side of the shielding wall 26 for engaging the conductive piece 13 of the busbar 11 from the back side. The upper end of the locking piece 27 is connected to the lower edge 25l of the peripheral wall 25 by an integral hinge 28. The integral hinge 28 is positioned approximately in the center in the left-right direction of the lower edge 25l of the peripheral wall 25. The locking piece 27 is integrally formed with the main body of the busbar case 20 via the integral hinge 28. The locking piece 27 is rotatable with the integral hinge 28 at its upper end as a pivot point. The locking piece 27 is displaceable between a closed position, which is close to (approximately parallel to) the back side of the shielding wall 26, and an open position, which is separated from the shielding wall 26.

[0025] Figure 7 is a rear view of a portion of the busbar module 10, showing the locking piece 27 in the open position. As shown in Figure 7, a locking claw 29 is integrally formed on the end of the locking piece 27 that is separated from the integral hinge 28. A locking portion (not shown) is formed on the back surface of the shielding wall 26 at a position opposite to the locking claw 29 of the locking piece 27. The locking piece 27 is locked in the closed position when the locking claw 29 engages with the locking portion. When the conductive piece 13 of the busbar 11 is set on the back surface of the shielding wall 26, and the locking piece 27 is locked in the closed position in this state, the conductive piece 13 of the busbar 11 is pressed down by the locking piece 27. As a result, the busbar 11 is locked by the locking piece 27 at approximately the center position in the left-right direction of the conductive piece 13.

[0026] Figure 8 is a cross-sectional view of the busbar module 10 along the line VIII-VIII in Figure 5. Arrow F in Figure 8 points to the front surface of the busbar module 10. As shown in Figures 5, 6, and 8, a protruding piece 31 is integrally formed on one end of the conductive piece 13 of the busbar 11 (near the connection point with one of the connecting seat portions 12), projecting outward in the left-right direction.

[0027] At positions corresponding to the protruding piece 31 of the busbar case 20, an insertion hole 32 into which the protruding piece 31 is inserted from the inside in the left-right direction, and a locking wall 33 are provided. The locking wall 33 is a wall continuous with the insertion hole 32 and abuts against the back surface of the protruding piece 31 inserted into the insertion hole 32. The busbar 11 restricts the displacement of the base of one of the conductive pieces 13 toward the back side by the back surface of the protruding piece 31 abutting against the locking wall 33. In this embodiment, the protruding piece 31 contacts the busbar case 20 (locking wall 33) to form a displacement restricting portion that restricts the displacement of the connecting seat portion 12 toward the rear side.

[0028] Next, we will explain how to assemble the busbars 11 to the busbar case 20. The locking piece 27 of the busbar case 20 is left open beforehand. In this state, the busbar 11 is placed on the back side of the busbar case 20, and the busbar 11 is tilted in the left-right direction so that the tip of the protruding piece 31 of the busbar 11 is inserted into the insertion hole 32 of the busbar case 20.

[0029] Next, as shown in Figure 8, the orientation of the busbar 11 is changed so that it is approximately parallel to the back surface of the shielding wall 26. At this time, the left and right connecting seats 12 of the busbar 11 are positioned within the corresponding openings 23 of the busbar case 20, and the conductive pieces 13 of the busbar 11 are positioned close to the back surface of the shielding wall 26 of the busbar case 20.

[0030] Next, the locking piece 27 of the busbar case 20 is closed, and the locking claw 29 of the locking piece 27 is engaged with the locking part. As a result, the conductive piece 13 of the busbar 11 is engaged with the locking piece 27, and the busbar 11 is assembled to the busbar case 20.

[0031] The busbar module 10, in which the busbars 11 are assembled in the busbar case 20, is mounted on the battery pack, and the left and right connection seats 12 of the busbars 11 are connected to the corresponding electrodes 1 of the battery pack by nuts 15. After this, an insulating cover 30 is attached to the surface side of the busbar case 20.

[0032] Figure 9 is an enlarged plan view of a portion of the busbar module 10 with the insulating cover 30 attached. As shown in Figure 9, the vertical width of the insulating cover 30 is slightly wider than the vertical width of the left and right connection seats 12 of the busbar 11. The vertical width of the insulating cover 30 is set so that it does not overlap with the entire area of ​​the conductive piece 13 of the busbar 11 in the front-to-back direction. The area of ​​the conductive piece 13 of the busbar 11 that does not overlap with the insulating cover 30 in the front-to-back direction is covered on its surface side by the shielding wall 26. Therefore, the area of ​​the conductive piece 13 that does not overlap with the insulating cover 30 in the front-to-back direction is insulated from the outside by the shielding wall 26.

[0033] As described above, the busbar module 10 of this embodiment includes a shielding wall 26 in the busbar case 20 that shields the surface side of the conductive piece 13 of the busbar 11. A locking piece 27 that engages with the conductive piece 13 of the busbar 11 is arranged on the back side of the shielding wall 26. In this case, since the conductive piece 13 of the busbar 11 is engaged with the locking piece 27 on the back side of the shielding wall 26, the surface side of the conductive piece 13 of the busbar 11 can be electrically shielded by the shielding wall 26 when the busbar 11 is supported in the busbar case 20. For this reason, the busbar module 10 of this embodiment can have a vertical width of the insulating cover 30 narrower than the width that the insulating cover 30 completely covers the surface side of the conductive piece 13. Therefore, when the busbar module 10 of this embodiment is adopted, the insulating cover 30 that covers the surface side of the busbar 11 can be made smaller and lighter.

[0034] Furthermore, in this embodiment, the busbar module 10 has a locking piece 27 that supports the conductive piece 13 of the busbar 11, which is integrally formed with the main body of the busbar case 20 via an integral hinge 28. With this configuration, the busbar module 10 of this embodiment does not require the separate assembly of the locking piece 27 to the busbar case 20. Therefore, adopting this configuration makes it possible to simplify the assembly of the busbar module 10.

[0035] Furthermore, in this embodiment, the busbar module 10 has a shape in which the conductive piece 13 of the busbar 11 extends in a substantially U-shape in a direction intersecting the direction in which the pair of connecting seat portions 12 are aligned. This shape of the conductive piece 13 allows the busbar module 10 to avoid interference with bolt fastening portions, equipment operating portions, etc., that protrude from the outer surface of the battery pack. Even with this shape of conductive piece 13 extending in a substantially U-shape, the busbar module 10 of this embodiment can stably support the conductive piece 13 on the back side of the shielding wall 26. Therefore, by adopting the busbar module 10 with this configuration, the support stability for the busbar 11 can also be improved.

[0036] Furthermore, in this embodiment, the busbar module 10 is provided with a protruding piece 31 (displacement restricting portion) near one of the connection seat portions 12 of the busbar 11, which restricts the displacement of the connection seat portion 12 toward the back side. With this structure, while the conductive piece portion 13 of the busbar 11 is supported by the locking piece 27, it becomes possible to restrict the displacement of the busbar 11 near the connection seat portion 12 by the locking piece 27. Therefore, by adopting this configuration, it becomes possible to further improve the support stability of the busbar 11.

[0037] While embodiments of the present disclosure have been described above, these embodiments are provided as examples and are not intended to limit the scope of the present disclosure. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the present disclosure.

[0038] For example, in the above embodiment, a battery pack (battery assembly) is used as the object to which the busbar module is attached, but the object to which the busbar module is attached is not limited to a battery pack. The object to which it is attached can be any component having terminals for conducting electricity, such as a terminal block having terminals for relaying.

[0039] Furthermore, although the busbar 11 in the above embodiment has a shape in which a substantially U-shaped conductive piece 13 extends in one direction from a pair of connecting seats 12, the shape of the busbar 11 is not limited to this shape. The conductive piece of the busbar may have a shape other than a substantially U-shape as long as it extends in one direction from a pair of connecting seats.

[0040] Furthermore, in the above embodiment, a locking piece 27 that engages the conductive piece 13 of the busbar 11 with the back side of the shielding wall 26 is integrally provided on the main body of the busbar case 20 via an integral hinge 28. However, the locking piece 27 can also be configured as a separate part from the main body of the busbar case 20. In this case, the locking piece 27 may be locked to the main body of the busbar case 20 by engagement with protrusions and recesses or the like.

[0041] Furthermore, in the above embodiment, the connection seat portion 12 of the busbar 11 is connected to the electrode 1, which is the terminal, by tightening (fastening) with a nut 15. However, the connection between the connection seat portion 12 and the terminal is not limited to fastening. Other methods besides fastening can be used to connect the connection seat portion 12 and the terminal. For example, the connection seat portion 12 may be connected to the terminal by welding or the like. [Explanation of symbols]

[0042] 1...Electrode (terminal) 10…Busbar Module 11…Bus bar 12…Connecting seat 13...Conducting piece 20... Bus bar case 23…Aperture 26…shielding wall 27… Locking piece 28…Integral Hinge 30…Insulating cover 31…Protruding piece (displacement restricting part)

Claims

1. A busbar having a pair of connecting seats that are connected to corresponding terminals of the object to be attached, and a conductive piece that connects the pair of connecting seats, Each of the aforementioned connection seats has an opening that exposes the surface side opposite to the object to be mounted, and the busbar case is made of insulating resin and houses the busbar, The busbar case is detachably attached to the busbar case and includes an insulating cover that covers the surface side of the busbar, The busbar case includes a shielding wall that shields the surface side of the conductive piece, On the back side of the shielding wall, which is on the same side as the object to be attached, a locking piece is provided for engaging the conductive piece of the busbar. Busbar module.

2. The locking piece is integrally provided with the busbar case via an integral hinge. The busbar module according to claim 1.

3. The conductive piece of the busbar extends in a substantially U-shape in a direction intersecting the direction in which the pair of connecting seats are aligned. The busbar module according to claim 1 or 2.

4. The busbar is provided with a displacement restricting portion near at least one of the connection seats, which contacts the busbar case and restricts the displacement of the connection seat toward the rear side. The busbar module according to claim 3.

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