Protective cover for bus bar

Abstract

To provide a protection cover of a bus bar capable of preventing deterioration of coupling strength of a coupling part and a coupling receiving part provided on a side wall while thinning the side wall.SOLUTION: A protective cover (3) for a bus bar (4) is mounted on the bus bar (4) by coupling a first cover (1) and a second cover (2), wherein the first cover (1) includes an inner wall (12) covering a side surface (43) of the bus bar (4) and an outer wall (13) parallel to the inner wall (12) on a first protective surface (11) covering a first flat surface (41) of the bus bar, a coupling receiving portion (131) is provided on the outer wall (13), and the second cover (2) includes an intermediate wall (22) to be fitted between the inner wall (12) and the outer wall (13) of the first cover (1) on a second protective surface (21) covering a second flat surface (42) of the bus bar (4). The coupling portion 221 is provided on the intermediate side wall 22.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a protective cover that is attached to a bus bar that connects batteries of an electric vehicle, for example. [Background technology]

[0002] For example, bus bars connecting the batteries of electric vehicles are conductor plates formed to fit the installation location, and the main body, excluding the connection terminals, is insulated to prevent damage and short circuits. Insulation structures include an insulating coating formed on the main body of the bus bar and a protective cover attached to the main body of the bus bar. Insulating coatings are expensive to form and have unstable thicknesses, making it difficult to reliably prevent damage and short circuits. For this reason, protective covers, which are inexpensive to manufacture and reliably prevent damage and short circuits, are often used for bus bar insulation structures (Patent Document 1, Patent Document 2).

[0003] Patent Document 1 discloses a protective cover consisting of a protector portion that covers the bus bar from both the front and back, and a cover. The protective cover disclosed in Patent Document 1 has a contact portion that presses against the bus bar on the protective surface that covers the flat surface of the bus bar (Patent Document 1, Claim 1). The protector portion and cover are each provided with a pair of connecting portion and connecting receiving portion, and are integrated by deforming a flexible portion between the connecting portion and the connecting portion to connect the connecting portion and the connecting receiving portion (Patent Document 1, [Claim] 6,

[0011] ).

[0004] Patent Document 2 discloses a bi-fold protective cover (cover) to be attached to a bus bar having a rising portion that is bent from a straight portion. The protective cover disclosed in Patent Document 2 has a receiving cover portion and a pressing cover portion that cover the rising portion of the bus bar, respectively, provided on the upper and lower covers, and has an upright wall and a sliding wall that are perpendicular to the straight portion of the bus bar (Patent Document 2, Claim 1). The upper and lower covers are integrated by connecting a connecting portion (locking portion) and a connecting receiving portion (lock receiving portion) that are provided on the side walls provided on the side edges of the protective surface that covers the flat surface of the bus bar (Patent Document 1,

[0033] ). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-057459 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-041706 Summary of the Invention [Problem to be solved by the invention]

[0006] In recent years, in order to reduce the volume occupied by batteries in electric vehicles, there has been a demand for miniaturization of the batteries themselves, as well as miniaturization of the bus bars that connect the batteries together and the protective covers. One possible way to miniaturize the protective covers is to first thin the flat surfaces and side walls that make up the protective covers. However, when the flat surfaces and side walls of the protective covers disclosed in Patent Document 1 and Patent Document 2 are thinned, the side walls become more susceptible to elastic deformation, resulting in a problem of reduced connection strength of the connecting portions and connecting receptacles provided on the side walls.

[0007] The problem of reduced connection strength between the coupling portion and the coupling receiver is caused by the tendency of both the coupling portion and the coupling receiver to elastically deform, and if the elastic deformation of at least one of the side walls can be suppressed, the reduction in connection strength between the coupling portion and the coupling receiver can be prevented. Therefore, with the aim of reducing the size of the busbar protective cover, the researchers studied the structure or configuration of the side walls so that the protective surface covering the flat surface of the busbar and the side walls on the side edges of the protective surface can be made thinner while still preventing a reduction in connection strength between the coupling portion and the coupling receiver provided on the side walls. [Means for solving the problem]

[0008] As a result of these studies, the researchers developed a protective cover for a busbar that is attached to a busbar by joining a first cover and a second cover, characterized in that the first cover has a first protective surface that covers a first flat surface of the busbar, an inner wall that covers the side of the busbar, and an outer wall parallel to the inner wall, with a coupling receiving portion provided on the outer wall, and the second cover has a second protective surface that covers a second flat surface of the busbar, with an intermediate side wall that fits between the inner wall and outer wall of the first cover, with a coupling portion provided on the intermediate side wall.

[0009] In the present invention, the width direction perpendicular to the extension direction of the first cover and the second cover is defined as the left-right direction, and the sides of the first cover and second cover attached to the joined bus bar that can be seen from the outside are defined as the outside, and the sides facing the bus bar are defined as the inside. Therefore, in the first cover attached to the bus bar by joining it to the second cover, the side wall facing the bus bar is defined as the inside wall, and the side wall visible from the outside is defined as the outside wall. Furthermore, the outside of the first protective surface and the second protective surface is defined as the outside surface, and the inside is defined as the inside surface.

[0010] The first cover and the second cover may be configured as two completely separable parts, or as one part connected by a hinge. In the case where the first cover and the second cover are configured as two completely separable parts, the inner and outer walls of the first cover are provided as a pair in a symmetrical positional relationship along the left and right side edges, and the middle side walls of the second cover are provided as a pair in a positional relationship to fit into the inner and outer walls of the first cover, respectively, along the left and right side edges. In the case where the covers are configured as one part connected by a hinge, the inner and outer walls of the first cover are provided along the right side edge in a symmetrical positional relationship with the left side edge where the hinge is provided, and the middle side wall of the second cover is provided along the right side edge in a positional relationship to fit into the inner and outer walls of the first cover.

[0011] In the protective cover of the present invention, the first and second covers are integrated by fitting the intermediate side wall of the second cover between the inner and outer walls of the first cover and connecting the connecting portion provided on the intermediate side wall to the connecting receiving portion provided on the outer wall. Here, the intermediate side wall is held in position by being fitted between the inner and outer walls. As a result, even if all the side walls are made thin, elastic deformation of the intermediate side wall provided with the connecting portion is suppressed, and the connecting strength between the connecting portion provided on the intermediate side wall and the connecting receiving portion provided on the outer wall is not reduced.

[0012] The connecting portion and the connecting receiving portion are exemplified by a combination of a connecting portion that is a protrusion that protrudes toward the outer wall and a connecting receiving portion that is a recess or opening that the protrusion fits into. As with conventional protective covers, the combination of the connecting portion and the connecting receiving portion is arranged at appropriate intervals at the same position or at offset positions in the extension direction of the left and right intermediate side walls and the outer wall so that the first cover and the second cover are integrated equally over the entire area.

[0013] In the protective cover of the present invention, the first cover may be connected to the connecting walls at both ends of the inner and outer walls in the extension direction, and the second cover may have an intermediate side wall that fits between the inner and outer walls of the first cover excluding the connecting wall. The connecting wall increases the rigidity of the inner and outer walls and strengthens the constraint of the intermediate side wall that fits between the inner and outer walls. In the protective cover of the present invention, the first cover may be provided with a first fixing portion on the first protective surface that abuts against a first flat surface of the bus bar, and the second cover may be provided with a second fixing portion on the second protective surface that abuts against a second flat surface of the bus bar. The first fixing portion and the second fixing portion may be provided at an appropriate interval at the same position or at offset positions in the extension direction of the first protective surface and the second protective surface. [Effects of the Invention]

[0014] The protective cover of the present invention restrains the intermediate side wall of the second cover fitted between the inner and outer walls of the first cover, suppressing elastic deformation of the intermediate side wall provided with the connecting portion and preventing a decrease in the connecting strength between the connecting portion and the connecting receiving portion. This allows the inner, outer, and intermediate side walls to be made thinner, thereby achieving a compact protective cover. Furthermore, the protective cover of the present invention also improves insulation because the intermediate side wall and the inner wall overlap without any gaps over their entire area.

[0015] Furthermore, the protective cover of the present invention connects both ends of the inner and outer walls with connecting walls, thereby strengthening the restraint of the intermediate side wall fitted into the inner and outer walls and increasing the connection strength of the connecting portion and the connection receiving portion. Furthermore, the protective cover of the present invention abuts the first fixing portion or the second fixing portion against the first flat surface or the second flat surface of the bus bar, thereby suppressing rattle of the bus bar and preventing a decrease in the connection strength between the connecting portion and the connection receiving portion. As a result of this, the connection strength of the connecting portion and the connection receiving portion is generally increased, which allows the connecting portion and the connection receiving portion to be made smaller, and therefore the protective cover to be made smaller. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a perspective view of an example (present example) of a bus bar fitted with a protective cover to which the present invention is applied, as viewed from the front side. [Figure 2] FIG. 2 is a perspective view of the bus bar of the present embodiment, as viewed from the rear side. [Figure 3] FIG. 2 is a left side view of the bus bar of the present example. [Figure 4] 3 is a perspective view of a first cover of the protective cover of this example, viewed from the inside. FIG. [Figure 5] FIG. 2 is a perspective view of a first cover of the protective cover of this example, as viewed from the outside. [Figure 6] FIG. 2 is a left side view of a first cover in the protective cover of this example. [Figure 7] FIG. 2 is a front view showing the inside of a first cover of the protective cover of this example. [Figure 8] FIG. 7 is an enlarged view of the portion indicated by the arrow B in FIG. 6. [Figure 9]FIG. 2 is a perspective view of the second cover of the protective cover of this example, as viewed from the inside. [Figure 10] FIG. 2 is a perspective view of the second cover of the protective cover of this example, as viewed from the outside. [Figure 11] FIG. 2 is a left side view of a second cover in the protective cover of this example. [Figure 12] FIG. 2 is a rear view showing the inside of the first cover of the protective cover of this example. [Figure 13] FIG. 8 is an enlarged view of the portion indicated by the arrow C in FIG. 7. [Figure 14] FIG. 4 is an enlarged view of the portion indicated by the arrow A in FIG. 3. [Figure 15] 14A and 14B are cross-sectional views taken along the line DD in FIG. [Figure 16] 14A and 14B are cross-sectional views taken along the line E-E in FIG. [Figure 17] FIG. 10 is a perspective view of a first cover of a protective cover according to another example, viewed from the inside. [Figure 18] FIG. 10 is a perspective view of a second cover in a protective cover of another example, as viewed from the outside. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience of illustration, the outer surface of the first protective surface 11 will be referred to as the back surface of the first cover 1, the inner surface of the first protective surface 11 will be referred to as the front surface of the first cover 1, the outer surface of the second protective surface 21 will be referred to as the front surface of the second cover 2, and the inner surface of the second protective surface 21 will be referred to as the back surface of the second cover 1. As shown in FIGS. 1 to 3, for example, the protective cover 3 of the present invention is composed of the first cover 1 and the second cover 2 that are bent in a manner similar to the bent bus bar 4. In this example, the protective cover 3 is composed of two parts, the first cover 1 and the second cover 2, which are completely separate. By attaching the first cover 1 and the second cover 2, which are joined without any gaps, the main body of the bus bar 4, excluding the connection terminals 44, is physically and electrically protected.

[0018] The busbar 4 is a copper or aluminum plate formed to fit the installation location. The busbar 4 has a first flat surface 41 and a second flat surface 42 that are identical and parallel to each other, and left and right side surfaces 43 that are equivalent to the thickness of the busbar 4. The first flat surface 41, the second flat surface 42, and the left and right side surfaces 43 are covered by the protective cover 3, except for connection terminals 44 that extend from the main body and have fixing holes 441 through which fixing bolts (not shown) are inserted. In this example, the protective cover 3 has a first protective surface 11 and an inner wall 12 of the first cover 1 that cover the first flat surface 41 and the left and right side surfaces 43 of the busbar 4, and a second protective surface of the second cover 2 that covers the second flat surface 42 of the busbar 4.

[0019] 4 to 7, first cover 1 is a member bent in a similar manner to busbar 4, and has a pair of left and right inner walls 12 and outer walls 13 in a symmetrical relationship, which extend parallel along the left and right side edges of first protective surface 11 that covers first flat surface 41 (see FIG. 2) of busbar 4. First cover 1 is a one-piece molded product made of insulating resin (for example, polyolefin such as polyethylene or polypropylene, polyester such as PBT or PET, polyamide such as nylon 6, nylon 6,6, or nylon 4,6, etc.).

[0020] The inner wall 12 and the outer wall 13 in this example are curved along the left and right side edges of the first protective surface 11, which is bent in a similar manner to the bus bar 4. The left and right inner walls 12 are formed so that the distance between their inner surfaces is slightly wider than the width of the bus bar 4 and slightly higher than the thickness of the bus bar 4, and cover the left and right side surfaces 43 of the bus bar 4 when the first cover 1 is attached to the bus bar 4. The left and right outer walls 13 are provided with three coupling receiving portions 131 at approximately equal intervals in the extension direction of the first cover 1. The inner wall 12 and the outer wall 13 in this example are connected at both ends in the extension direction by connecting walls 14. As a result, the first cover 1 in this example forms an enclosed space surrounded by the inner wall 12, the outer wall 13, and the connecting walls 14, and the intermediate side wall 22 of the second cover 2 is fitted into this enclosed space.

[0021] As shown in Fig. 8, the coupling receptacle 131 in this example has a shape in which a semicircular arc-shaped opening is connected to a groove extending from the edge of the outer wall 13. The coupling receptacle 131 is an opening in the outer wall 13, but there is no opening in the inner wall 12, and the inner wall 12 blocks the coupling receptacle 13 from the inside (the inner wall 12 can be seen through the opening of the coupling receptacle 131 in Fig. 8). As a result, there is no gap in the first cover 1 that communicates between the inside and outside beyond the inner wall 12 and outer wall 13.

[0022] In addition, the first cover 1 of this example is provided with three first fixing portions 111, each having a substantially semicircular cross section that crosses from left to right, on the inside of the first protective surface 11. In this example, the first fixing portions 111 are arranged in a total of three locations on a straight line connecting the coupling receptacles 131 provided on the outer wall 13 or in the vicinity of said straight line. When the first cover 1 is attached to the bus bar 4, the first fixing portions 111 are pressed against the first flat surface 41 of the bus bar 4, preventing rattling of the first cover 1 relative to the bus bar 4 and suppressing the coupling receptacles 131 from moving and releasing the coupling with the coupling portions 221.

[0023] 9 to 12, second cover 2 is a member bent in a similar manner to busbar 4, and has a pair of left and right intermediate side walls 22 extending along the left and right side edges of second protective surface 21 that covers second flat surface 42 (see FIG. 1) of busbar 4. Like first cover 1, second cover 2 is a one-piece molded product made of insulating resin (for example, polyolefin such as polyethylene or polypropylene, polyester such as PBT or PET, or polyamide such as nylon 6, nylon 6,6, or nylon 4,6).

[0024] In this example, the intermediate side walls 22 are curved along the left and right side edges of the second protective surface 21, which is bent in a manner similar to the busbar 4. Each of the left and right intermediate side walls 22 is formed to be slightly narrower than the distance between the opposing wall surfaces of the inner wall 12 and the outer wall 13 of the first cover 1, and slightly lower than the inner wall 12 and the outer wall 13. The left and right intermediate side walls 22 are fitted into the closed space surrounded by the inner wall 12, the outer wall 13 and the connecting wall 14, with a length shorter than the inner wall 12 and the outer wall 13 by the length of two connecting walls 14. Each of the left and right intermediate side walls 22 is provided with three connecting portions 221 in the extension direction of the second cover 2, at the same positions as the connecting receptacles 131 of the first cover 1.

[0025] 13, the connecting portion 221 in this example has a shape in which a convex ridge with a triangular cross section that extends along the outer surface of the intermediate side wall 22, perpendicular to the inner surface of the second protective surface 21, is connected to a convex portion with a generally truncated cone shape that protrudes from the outer surface of the intermediate side wall 22, and the convex ridge and the convex portion protrude by the same amount from the outer surface of the intermediate side wall 22. The connecting portion 221 is a convex portion formed on the outer surface of the intermediate side wall 22, and is not an opening, and there is no gap that passes beyond the intermediate side wall 22 to communicate with the inside and outside of the second cover 2.

[0026] In addition, the second cover 2 of this example is provided with three second fixing portions 211, each having a substantially semicircular cross section that crosses from left to right, on the inside of the second protective surface 21. The second fixing portions 211 of this example are arranged in a total of three locations on a straight line connecting the coupling portions 221 provided on the intermediate side wall 22 or in the vicinity of said straight line. When the second cover 2 is attached to the bus bar 4, the second fixing portions 211 are pressed against the second flat surface 42 of the bus bar 4, preventing rattling of the second cover 2 relative to the bus bar 4 and suppressing the coupling portions 221 from moving and releasing the coupling with the coupling receptacle 131.

[0027] The first cover 1 and the second cover 2 are fitted with the intermediate side wall 22 of the second cover 2 between the inner wall 12 and the outer wall 13 of the first cover 1, with the bus bar 4 sandwiched therebetween, and the coupling portion 221 provided on the outer surface of the intermediate side wall 22 is coupled to the coupling receptacle 131 of the outer wall 13. As shown in Figure 14, the coupling portion 221 and the coupling receptacle 131 of this example are coupled together in such a way that the convex portion of the coupling portion 221 elastically deforms to push open the groove of the coupling receptacle 131, and when the convex portion reaches the semicircular arc-shaped opening, the groove returns to its original shape and closes, maintaining the state in which the convex portion is fitted into the semicircular arc-shaped opening. Furthermore, because the engagement receptacle 131 of the coupling portion 221 and the coupling receptacle 131 of this example is an opening, it is possible to visually confirm from the outside that the coupling portion 221 is properly fitted, making it easy to detect if the coupling is incomplete.

[0028] 15, the protective cover 3 of the present invention fits the intermediate side wall 22 of the second cover 2 between the inner wall 12 and the outer wall 13 of the first cover 1, suppressing elastic deformation of the positionally constrained intermediate side wall 22 and preventing a decrease in the bonding strength of the coupling portion 221 and the bonding receiving portion 131. As shown in FIG. 16, the protective cover 3 of this example presses the first fixing portion 111 against the first flat surface 41 of the bus bar 4 and the second fixing portion 211 against the second flat surface 42 of the bus bar 4, preventing rattling of the first cover 1 and the second cover 2 relative to the bus bar 4 and better preventing a decrease in the bonding strength of the coupling portion 221 and the bonding receiving portion 131 according to the present invention.

[0029] The protective cover 3, consisting of the first cover 1 and second cover 2 joined in this manner, covers the first flat surface 41 and side surface 43 of the bus bar 4 with the continuous first protective surface 11 and inner side wall 12 of the first cover 1, and covers the second flat surface 42 of the bus bar 4 with the second protective surface 21 of the second cover 2, thereby preventing damage to the bus bar 3. Furthermore, in the protective cover 3, the inner side wall 12 and intermediate side wall 22 overlap in the area where the coupling receptacle 131 is provided (see FIG. 15), and the outer side wall 13, inner side wall 12 and intermediate side wall 22 overlap in the area where the coupling receptacle 131 is not provided (see FIG. 16). This eliminates gaps connecting the inside and outside of the protective cover 3, improving insulation and preventing short circuits of the bus bar 3.

[0030] The effect of the present invention of preventing a decrease in the connection strength of the connecting portion 221 and the connecting receptacle 131 while thinning the inner side wall 12, the outer side wall 13, and the intermediate side wall 22 can be enjoyed regardless of the shapes of the connecting portion 221 and the connecting receptacle 131. Therefore, as shown in Figures 17 and 18, even in a protective cover that connects a second cover 2 in another example where the connecting portion 222 is a hooking claw and a first cover 1 in another example where the connecting receptacle 132 is an opening with a reinforcing frame, the overall size can be reduced by thinning the inner side wall 12, the outer side wall 13, and the intermediate side wall 22.

[0031] The first cover 1 provided with a coupling receptacle 132 of another example has the same structure as this example (see FIG. 4) and is formed using the same resin material as in this example except for the coupling receptacle 132, and has inner and outer walls 12 and 13, each of which has both ends in the extension direction connected to a connecting wall 14, provided symmetrically along the left and right side edges of the first protective surface 11, and three first fixing portions 111 are provided across the first protective surface 11. The second cover 2 provided with a coupling portion 221 of another example has the same structure as this example (see FIG. 9) and is formed using the same resin material as in this example except for the coupling portion 221, and has intermediate side walls 22 that fit into the inner and outer walls 12 and 13 and are provided symmetrically along the left and right side edges of the second protective surface 21, and three second fixing portions 211 are provided across the second protective surface 21. [Explanation of symbols]

[0032] 1 First Cover 11 1st protective surface 111 1st fixed part 12 Inner wall 13 Outer wall 131 Coupling receiver 132 Alternative coupling receiver 14 Connecting wall 2 Second cover 21 Second protective surface 211 Second fixed part 22 Intermediate side wall 221 Joint 222 Alternative Joint 3 Protective cover 4 Busbars 41 1st plane 42 Second plane 43 Side 44 connection terminal 441 Fixed hole

Claims

1. A bus bar protective cover that is attached to a bus bar by combining a first cover and a second cover, the first cover has a first protective surface that covers a first flat surface of the bus bar, an inner wall that covers a side surface of the bus bar, and an outer wall that is parallel to the inner wall, and the coupling receiving portion is provided on the outer wall; The second cover has a second protective surface covering the second flat surface of the bus bar, and an intermediate side wall that fits between the inner wall and the outer wall of the first cover, and a coupling portion is provided on the intermediate side wall. Protective cover for busbars.

2. The first cover is connected to the connecting wall at both ends in the extending direction of the inner wall and the outer wall, The second cover has an intermediate side wall that fits between the inner and outer walls of the first cover, excluding the connecting wall. The bus bar protective cover according to claim 1.

3. The first cover has a first fixing portion on a first protective surface that abuts against a first flat surface of the bus bar.

3. The bus bar protective cover according to claim 1 or 2.

4. The second cover has a second fixing portion on a second protective surface that abuts against the second flat surface of the bus bar.

3. The bus bar protective cover according to claim 1 or 2.

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