Busbar connection structure

Abstract

This provides a busbar connection structure that can reduce the clearance during insertion and minimize deformation resistance. [Solution] The busbar connection structure comprises a receiving busbar 1 and an inserting busbar 2 that is movable relative to the receiving busbar 1 and is inserted into the receiving busbar 1 side to connect with the receiving busbar 1. The opposing surfaces 11 and 21 of the receiving busbar 1 and the inserting busbar 2 are each formed in a tapered shape.

Description

Technical Field

[0001] This disclosure relates to a connection structure of a bus bar.

Background Art

[0002] Patent Document 1 describes a connection structure of a bus bar that can properly fix an input / output terminal electrically connected to a stator winding and a relay bus bar.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] With the trend towards BEV (Battery Electric Vehicle) conversion, the plate thickness tends to increase. Bolt fastening between bus bars requires a clearance in terms of structure. With a clearance, the axial force is lost due to the deformation resistance of the bus bar during fastening. When the plate thickness is large, the resistance increases in proportion to the square of the cross section.

[0005] An object of this disclosure is to provide a connection structure of a bus bar that can reduce the clearance during insertion and reduce the deformation resistance.

Means for Solving the Problems

[0006] A connection structure of a bus bar according to an aspect of an embodiment of the present invention includes a receiving-side bus bar and an insertion-side bus bar inserted on the receiving-side bus bar side and connected to the receiving-side bus bar, and the opposing surfaces of the receiving-side bus bar and the insertion-side bus bar are each formed in a tapered shape.

Effects of the Invention

[0007] According to this disclosure, it is possible to provide a busbar connection structure that can reduce the clearance during insertion and reduce deformation resistance. [Brief explanation of the drawing]

[0008] [Figure 1] A diagram showing the schematic configuration of the busbar connection structure according to the embodiment. [Figure 2] A diagram showing the schematic configuration of a busbar connection structure according to a modified embodiment. [Figure 3] A schematic diagram showing an example of a conventional busbar connection structure as a comparative example. [Modes for carrying out the invention]

[0009] The embodiments will be described below with reference to the attached drawings. To facilitate understanding of the explanation, the same reference numerals are used for identical components in each drawing whenever possible, and redundant explanations are omitted.

[0010] In the following explanation, the X, Y, and Z directions are perpendicular to each other. The X direction is the direction in which the tapered surface 11 of the receiving busbar 1 and the tapered surface 21 of the inserting busbar 2 face each other. The Z direction is the direction of movement of the inserting busbar 2 relative to the receiving busbar 1, with the negative Z direction being the insertion direction.

[0011] Figure 1 is a schematic diagram of the busbar connection structure according to the embodiment. Figure 1(A) is a side view seen from the negative Y direction side. Figure 1(B) is a cross-sectional view of AA in Figure 1(A).

[0012] In this embodiment, the term "busbar" refers to a conductive rod (electrode) made of metal, mainly copper, that conducts a large amount of high-voltage current from a power source to a distribution board, control panel, or operation panel. A pair of busbars is typically used, with one busbar connected to the power source side and the other connected to the supply side, such as a distribution board. By electrically connecting the pair of busbars, a large amount of high-voltage current can be supplied to the supply side. Busbars are sometimes also called "high-voltage connector busbars."

[0013] As shown in Figure 1, the busbar connection structure according to the embodiment includes a receiving busbar 1 and an insertion busbar 2 as the pair of busbars described above. One of the receiving busbar 1 and the insertion busbar 2 corresponds to the power supply busbar described above, and the other corresponds to the supply busbar described above.

[0014] In the example shown in Figure 1, the receiving busbar 1 is a plate-like component formed in a substantially L-shape, having a first portion 13 extending along the Z direction and a second portion 14 projecting from the Z-negative end of the first portion 13 toward the X-positive direction and extending along the X direction, as seen in the side view shown in Figure 1(A). On the other hand, the insertion busbar 2 is a plate-like component extending along the Z direction as seen in the side view shown in Figure 1(A). The length of the first portion 13 of the receiving busbar 1 and the insertion busbar 2 in the X direction in Figure 1(A) is the plate thickness. The length of the second portion 14 of the receiving busbar 1 in the Z direction in Figure 1(A) is the plate thickness.

[0015] The insertion busbar 2 is inserted into the receiving busbar 1 and connected to the receiving busbar. In the example in Figure 1, the insertion busbar 2 is movable relative to the receiving busbar 1 in the Z direction. By moving in the negative Z direction, the insertion busbar 2 approaches the receiving busbar 1, and when it reaches the positional relationship (connection position) with the receiving busbar 1 shown in Figure 1(A), it is connected to the receiving busbar 1, for example, by bolt fastening.

[0016] When the busbar connection structure is bolted, for example, as shown in Figure 1(A), a through hole 12 is provided at a predetermined position in the Z direction of the first portion 13 of the receiving busbar 1, extending through in the X direction. Similarly, a through hole 22 is provided at a predetermined position in the Z direction of the insertion busbar 2, extending through in the X direction. The two through holes 12 and 22 are formed with the same diameter. Also, as shown in Figure 1(A), the two through holes 12 and 22 are provided at positions that are coaxial when the insertion busbar 2 is inserted to the connection position with the receiving busbar 1. As a result, when the insertion busbar 2 is inserted to the connection position with the receiving busbar 1, the two through holes 12 and 22 form a single through hole that penetrates between the receiving busbar 1 and the insertion busbar 2. Then, a bolt 3 is inserted through the through hole formed in this way, and a nut 4 is screwed onto the shaft of the bolt 3 that is exposed from the through hole, thereby bolting the receiving busbar 1 and the inserting busbar 2 together.

[0017] Note that in Figure 1(A), for illustrative purposes, the shafts of the bolts 3 inserted through the through holes 12 and 22 are depicted with solid lines, but in reality, they are located inside the through holes 12 and 22, which are shown with dotted lines. The same applies to Figures 2(A) and 3.

[0018] In the case of BEVs (Battery Electric Vehicles), for example, a pair of busbars can connect the power source, such as a battery, to the power supply, such as a motor. As vehicles become BEVs, the high-voltage current flowing through the busbars increases, so the thickness of the busbars tends to increase.

[0019] Figure 3 is a schematic diagram showing an example of a conventional busbar connection structure as a comparative example. The receiving busbar 101 and the inserting busbar 102 shown in Figure 3 correspond to the receiving busbar 1 and the inserting busbar 2 shown in Figure 1, respectively. Also, the first part 103 and the second part 104 of the receiving busbar 101 correspond to the first part 13 and the second part 14 of the receiving busbar 1 shown in Figure 1, respectively.

[0020] In the conventional bus bar connection structure shown in FIG. 3, the plate thickness in the X direction of the first portion 103 of the receiving-side bus bar 101 and the insertion-side bus bar 102 is uniform throughout the Z direction. In the conventional bus bar connection structure shown in FIG. 3, the receiving-side bus bar 101 and the insertion-side bus bar 102 are bolted together by bolts 3 and nuts 4, similar to FIG. 1.

[0021] The bolt fastening between the receiving-side bus bar 101 and the insertion-side bus bar 102 needs to have a clearance C2 structurally. With the clearance C2, the axial force of the bolt 3 is lost due to the deformation resistance of the bus bars 101 and 102 during fastening. The magnitude of this deformation resistance increases as the plate thickness increases. More specifically, in the case of the example in FIG. 3, it increases with the square of the cross-sectional area along the XY plane of each bus bar 101 and 102. That is, in the conventional bus bar connection structure shown in FIG. 3, in order to increase the high-voltage current flowing through the bus bar, the thicker the plate thickness of the bus bar, the more difficult it is to ensure stable quality as a fastening body, such as deformation of the shaft parts of the bus bars 101 and 102 and the bolt 3.

[0022] In order to solve such a conventional problem, in the bus bar connection structure of this embodiment, the opposing surfaces 11 and 21 of the receiving-side bus bar 1 and the insertion-side bus bar 2 are each formed in a tapered shape. In the following description, the surfaces 11 and 21 may also be referred to as "tapered surfaces 11 and 21".

[0023] As shown in FIG. 1(A), the tapered surface 11 is formed as the surface facing the X negative direction side and the Z positive direction side of the first portion 13 of the receiving-side bus bar 1. The tapered surface 21 is formed as the surface facing the X positive direction side and the Z negative direction side of the insertion-side bus bar 2. Thereby, in the side view shown in FIG. 1(A), the first portion 13 is formed to be a right triangle with the tapered surface 11 as the hypotenuse, and the insertion-side bus bar 2 is formed to be a right triangle with the tapered surface 21 as the hypotenuse.

[0024] Furthermore, in the side view shown in Figure 1(A), the inclination angles of the two tapered surfaces 11 and 21 are formed to be approximately the same. As a result, when the insertion-side busbar 2 is inserted to the connection position with the receiving-side busbar 1 and bolted together, the two tapered surfaces 11 and 21 are positioned facing each other, as shown in Figure 1(A). Also, as shown in Figure 1(B), at each position in the Z direction, the two tapered surfaces 11 and 21 both extend parallel to each other along the Y direction. In other words, the cross-sectional shape of the first portion 13 of the receiving-side busbar 1 and the insertion-side busbar 2 along the XY plane is rectangular in shape, with the dimension (plate thickness) in the X direction continuously changing depending on the position in the Z direction. This allows for a constant clearance C1 between the two tapered surfaces 11 and 21. The clearance C1 in the embodiment shown in Figure 1 can be made smaller than the conventional clearance C2 in the comparative example shown in Figure 3.

[0025] In the busbar connection structure according to this embodiment, the clearance C1 can be reduced by tapering the busbars 1 and 2 in the thickness direction and bringing the busbar insertion trajectories closer together, thereby reducing the deformation resistance of busbars 1 and 2. In other words, the clearance C1 between each busbar 1 and 2 when inserting the insertion-side busbar 2 can be reduced, and the deformation resistance of each busbar 1 and 2 can be reduced. As a result, the busbar connection structure of this embodiment can suppress situations in which, for example, the shaft portion of busbars 1 and 2 or bolt 3 deforms, thereby ensuring stable quality as a fastener.

[0026] In this embodiment, the busbar connection structure is configured such that the opposing surfaces 11 and 21 of the receiving busbar 1 and the insertion busbar 2 are each tapered, and the orientation of the tapered surfaces 11 and 21 is not limited to the example in Figure 1. That is, the first portion 13 of the receiving busbar 1 and the cross-sectional shape of the insertion busbar 2 along the XY plane may not be rectangular.

[0027] Figure 2 shows a schematic configuration of a busbar connection structure according to a modified embodiment. Figure 2(A) is a side view seen from the negative Y direction. Figure 2(B) is a cross-sectional view of BB in Figure 2(A). The outlines of Figures 2(A) and (B) are the same as those of Figures 1(A) and (B), respectively.

[0028] As shown in Figure 2(B), the cross-sectional shape of the first portion 13A of the receiving busbar 1A and the insertion busbar 2A along the XY plane is trapezoidal. That is, the tapered surface 11A provided on the first portion 13A is formed as a surface facing the negative X direction and the positive Z direction, and also facing the negative Y direction. Similarly, the tapered surface 21A provided on the insertion busbar 2A is formed as a surface facing the positive X direction and the negative Z direction, and also facing the positive Y direction. Furthermore, as shown in Figure 2(B), at each position in the Z direction, both tapered surfaces 11A and 21A extend parallel to each other along the negative X direction and the positive Y direction. As a result, a constant clearance C1 can be maintained between the two tapered surfaces 11A and 21A, similar to the above embodiment.

[0029] The embodiments have been described above with reference to specific examples. However, this disclosure is not limited to these specific examples. Modifications made to these specific examples by those skilled in the art are also included within the scope of this disclosure, as long as they retain the features of this disclosure. The elements, their arrangement, conditions, shapes, etc., of each of the aforementioned specific examples are not limited to those illustrated and can be modified as appropriate. The elements of each of the aforementioned specific examples can be combined in different ways as appropriate, as long as no technical inconsistencies arise. [Explanation of Symbols]

[0030] 1 Receiving busbar 11 Tapered surface 2 Insertion side busbar 21 Tapered surface

Claims

[Claim 1] The receiving busbar, An insertion busbar is inserted into the receiving busbar and connected to the receiving busbar, Equipped with, The opposing surfaces of the receiving busbar and the insertion busbar are each formed in a tapered shape. Busbar connection structure.

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