Pipe joint for battery pack

Abstract

To provide a pipe joint for a battery pack which enables further improvement of assembly workability of a cooling pipe.SOLUTION: A pipe joint 50 is used in a cooling pipe of a battery pack 1 including a battery module 10 placed on a floor plate upper surface 20m. The pipe joint 50 includes: a vertical pipe 51 connected to the cooling pipe at the battery module 10 side; a lateral pipe 52 communicating with the vertical pipe 51 and connected to a cooling pipe at the floor plate 20 side; a fixing flange 55 provided radially outside and separated from the vertical pipe 51 and fitted in a housing recessed part 21 at the floor plate 20 side so as to be rotatable in a circumferential direction; and displacement absorption parts 56 provided between the vertical pipe 51 and the fixing flange 55 and disposed therebetween so as to allow radial movement of the fixing flange 55 relative to the vertical pipe 51.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a pipe joint used for cooling pipes of a battery pack in which a battery module is housed in a battery case. [Background technology]

[0002] In this type of assembled battery, a pipe joint is used to interconnect the cooling pipes on the battery case side and the cooling pipes on the battery module side housed within the battery case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-159687 A Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of battery pack pipe joint, it may be difficult to fit the cooling pipe and the pipe joint in the intended position due to the influence of component tolerances and assembly tolerances. In response to this, for example, Patent Document 1 discloses a structure that can absorb misalignment in the axial direction between the vertical hole and the long pipe by inserting a displacement absorbing part such as a bellows between the long pipe and the vertical hole.

[0005] However, while the technology described in Patent Document 1 assumes the absorption of displacement due to misalignment in the axial direction between the vertical hole and the long pipe, it does not take into consideration a pipe structure in which the entire pipe is continuously piped vertically and horizontally, such as the fitting of the cooling pipe on the battery module side with the cooling pipe on the battery case side, and is therefore insufficient for application to a pipe joint for a battery pack. Also, a structure in which a fastener such as a grommet made of an elastic body is used as a measure to absorb misalignment between multiple pipes at the pipe connection part is known, but this increases the number of parts and reduces the ease of assembly at the pipe connection part, and there is still room for further study. Therefore, the present invention has been made with attention to such problems, and an object of the present invention is to provide a pipe joint for a battery assembly that can further improve the ease of assembly of cooling piping at pipe connection parts in a battery assembly in which the entire cooling piping is piped continuously vertically and horizontally. [Means for solving the problem]

[0006] In order to solve the above problems, a piping joint for a battery pack according to one embodiment of the present invention is a piping joint used for cooling piping of a battery pack comprising a battery case and a battery module housed within the battery case and placed on a floor plate of the battery case, and comprises a vertical pipe connected to the cooling piping on the battery module side, a horizontal pipe communicating with the vertical pipe and connected to the cooling piping on the floor plate side, a fixed flange provided at a distance radially outward from the vertical pipe and fitted into a housing recess on the floor plate side so as to be rotatable in the circumferential direction, and a displacement absorbing portion provided between the vertical pipe and the fixed flange and capable of allowing radial movement of the fixed flange relative to the vertical pipe. Effect of the Invention

[0007] According to the present invention, the workability of assembling the cooling pipes at the pipe connection portion of the battery pack can be further improved. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a schematic exploded perspective view illustrating an embodiment of a cooling pipe in a battery pack according to an aspect of the present invention. [Diagram 2] FIG. 2 is a schematic exploded perspective view illustrating the cooling piping on the upper surface of the floor plate shown in FIG. [Diagram 3] 2A and 2B are cross-sectional views for explaining the cooling piping of the floor plate shown in FIG. 1, where FIG. 2A shows the XX cross-section in FIG. 1 and FIG. 2B shows the YY cross-section in FIG. [Figure 4] 3 is an explanatory diagram of a T-shaped joint to be placed at the pipe connection portion of the cooling pipe on the upper surface of the floor plate shown in FIG. 2, where (a) is an oblique view, (b) is a plan view, (c) is a front view, and (d) is a left side view. [Diagram 5] 3A to 3E are explanatory diagrams of an L-shaped joint to be placed at the pipe connection portion of the cooling pipe on the upper surface of the floor plate shown in FIG. 2, where (a) is a perspective view, (b) is a plan view, (c) is a front view, (d) is a left side view, and (e) is a right side view. [Figure 6] 3 is an explanatory diagram of a central fixed cover placed at the pipe connection portion of the cooling pipe on the upper surface of the floor plate shown in FIG. 2, where (a) is an oblique view seen from the top side, (b) is an oblique view seen from the back side, (c) is a plan view, (d) is a front view, (e) is a back view, (f) is a left side view, and (g) is a right side view. [Figure 7] 3 is an explanatory diagram of an end fixing cover to be placed at the pipe connection portion of the cooling pipe on the upper surface of the floor plate shown in FIG. 2, where (a) is an oblique view seen from the top side, (b) is an oblique view seen from the back side, (c) is a plan view, (d) is a front view, (e) is a back view, (f) is a left side view, and (g) is a right side view. [Figure 8] FIG. 2 is an exploded perspective view for explaining the structure of the pipe connection portion shown in FIG. 1, showing the pipe connection portion using a T-joint. [Figure 9] FIG. 2 is an exploded perspective view for explaining the structure of the pipe connection portion shown in FIG. 1, showing the pipe connection portion using an L-shaped joint. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The battery pack pipe joint according to this embodiment is an example used for cooling pipes of a battery pack including a plurality of battery modules. This type of battery pack is mounted on a vehicle such as an electric vehicle. It should be noted that the drawings are schematic. Therefore, it should be noted that the relationship and ratio between thickness and planar dimensions are different from the actual ones, and the drawings include parts in which the relationship and ratio between dimensions are different from each other. In addition, the embodiments shown below are examples of devices and methods for embodying the technical idea of ​​the present invention, and the technical idea of ​​the present invention does not specify the materials, shapes, structures, arrangements, etc. of the components to the embodiments described below.

[0010] [Battery pack and its cooling piping] 1, the battery pack 1 according to this embodiment is configured by housing a plurality of battery modules 10 inside a battery case 9, which is a housing. For ease of explanation, the following explanation will be made with the Y direction in the figure representing the front and rear, the near side representing the front, the X direction representing the left and right, and the Z direction representing the top and bottom.

[0011] As shown in the figure, multiple battery modules 10 (two in the example shown in the figure) are placed on an upper surface 20m of a floor plate 20 that forms the bottom of a battery case 9. Each battery module 10 has a roughly rectangular parallelepiped outer shape, and is placed and fixed on the upper surface 20m of the floor plate 20 with the direction along its long side being the front and rear.

[0012] Two heat exchangers 11 are arranged in each battery module 10 so as to cover the front and rear end faces of the approximately rectangular parallelepiped. Each heat exchanger 11 is provided with a pair of water supply and drainage ports 12 on both the left and right sides of the lower end, and cooling water introduced into the heat exchanger 11 from one water supply and drainage port 12 is discharged from the other water supply and drainage port 12.

[0013] [Battery assembly floor plate] The floor plate 20 is a plate-like member made of metal (aluminum alloy) having a rectangular shape in a plan view, and has a plurality of piping connections provided at positions facing the positions of the plurality of water supply and drainage ports 12 of each battery module 10 placed on its upper surface 20m. In this embodiment, the water supply and drainage ports 12 are provided at eight positions for two battery modules 10 as the plurality of piping connections, so that the upper surface 20m of the floor plate 20 has piping connections at a total of eight positions facing the water supply and drainage ports 12.

[0014] In this embodiment, a water supply pipe 4 and a drain pipe 5 are arranged on the left and right sides of the front side of the figure, and are arranged so that the cooling water supplied from the water supply pipe 4 is discharged from the drain pipe 5 after circulating through the heat exchangers 11 of each battery module 10. The white arrows in the figure show an image of the cooling water supplied from the water supply pipe 4 being discharged from the drain pipe 5 after circulating through the heat exchangers 11 of each battery module 10.

[0015] [Floor plates and piping connections] 2 and 3 show the piping connections of the floor plate 20. In this embodiment, in order to circulate cooling water to the heat exchangers 11 of each battery module 10, as shown in Figures 2 and 3, end connecting pipes 2 are piped along the front-to-rear direction at the left and right positions of the front side of the figure, and a central connecting pipe 3 is piped along the left-to-right direction at the center position of the front side of the figure.

[0016] Here, T-shaped joints 50 and L-shaped joints 60 are disposed at the eight pipe connection portions as pipe joints for connecting a plurality of cooling pipes to communicate the insides of the pipes. In the piping connection section of this embodiment, T-shaped joints 50 are used for the two piping joints connected to the water supply pipe 4 and the drain pipe 5 located on the left and right sides of the front side of the figure, which connect three cooling pipes vertically and horizontally to interconnect the insides of the pipes, and L-shaped joints 60 are used for the other six piping joints, which connect two pipes vertically and horizontally to interconnect the insides of the pipes.

[0017] [T-joint] 4, T-joint 50 has vertical pipe 51 and horizontal pipe 52 communicating with vertical pipe 51. Around the open tip portions of vertical pipe 51 and horizontal pipe 52, multi-stage cylindrical protrusions (so-called bamboo shoots) for piping connection are formed. In addition, an annular O-ring groove is formed in the middle of the vertical pipe 51, and an O-ring is fitted into it. At two intended installation positions on the left and right (see FIG. 2), the vertical pipe 51 is connected to water supply and drainage ports 12 (see FIG. 1), which are cooling piping on the battery module 10 side. In addition, the horizontal pipe 52 communicates with the vertical pipe 51, and is connected to the water supply pipe 4, drain pipe 5, and end connection pipe 2, which are cooling piping on the floor plate 20 side of the battery case 9.

[0018] Furthermore, in the T-joint 50 of this embodiment, a disk-shaped base flange 53 is provided coaxially with the vertical pipe 51 above the horizontal pipe 52, and an annular fixed flange 55 is provided at approximately the same height and spaced apart radially outward from the base flange 53. The fixed flange 55 is disposed so as to surround the outer periphery of a plurality of U-shaped arms 56, and is integrated with the base flange 53 via the plurality of U-shaped arms 56.

[0019] In the T-joint 50 of this embodiment, the fixed flange 55, the base flange 53 and the displacement absorbing section 56 are made of an elastic material (rubber, elastomer, resin) that can be molded as one piece, and are integrally formed by two-color molding. In this embodiment, the base flange 53 is disposed between the U-shaped arm 56 and the vertical pipe 51, and the multiple U-shaped arms 56 are disposed in each direction that is evenly spaced in the circumferential direction of the vertical pipe 51.

[0020] A plurality of U-shaped arms 56 are provided between the base flange 53 and the fixed flange 55. The plurality of U-shaped arms 56 are displacement absorbing parts interposed to allow radial movement of the fixed flange 55 relative to the base flange 53. The base flange 53 of the present embodiment has a plurality of (eight in the example shown in the figure) exhaust ports 54 equally spaced in the circumferential direction, which are formed to penetrate the base flange 53 in a generally rectangular shape in the vertical direction.

[0021] In particular, the U-shaped arm 56 in this embodiment has a base side arm 57 connected to the base flange 53 side, a U-shaped portion 58, and a fixed side arm 59 connected to the fixed flange 55 side, and the fixed side arm 59 connected to the fixed flange 55 side is longer than the base side arm 57. The fixing flange 55 is fitted into the accommodation recess 21 on the floor plate 20 side of the battery case 9 at two intended mounting positions (see FIG. 2). In this embodiment, the outer shape of the portion of the fixing flange 55 to be fixed is circular. Furthermore, the thickness of the U-shaped arm 56 and the base flange 53 is thinner than the thickness of the fixing flange 55, and a step is provided in the Z direction.

[0022] [L-type joint] 5, the L-type joint 60 has a vertical pipe 61 and a horizontal pipe 62 communicating with the vertical pipe 61. A multi-stage cylindrical protrusion (so-called bamboo shoot) for piping connection is formed around the open end portion of the vertical pipe 61 and the horizontal pipe 62. Note that the L-type joint 60 of this embodiment has a basically similar configuration to the above-mentioned T-type joint 50 except that the shape of the pipeline is L-shaped, so in the following explanation, corresponding configurations will be referred to by the same names and the tens digit of the reference numerals will be in the 60s.

[0023] The L-shaped joint 60 has an annular O-ring groove formed in the middle of the vertical pipe 61, into which an O-ring is fitted. At six intended installation positions (see FIG. 2), the vertical pipe 61 is connected to the water supply and drainage ports 12 (see FIG. 1), which are cooling piping on the battery module 10 side. In addition, the horizontal pipe 62 communicates with the vertical pipe 61, and is connected to the water supply pipe 4, drain pipe 5, and end connection pipe 2, which are cooling piping on the floor plate 20 side of the battery case 9.

[0024] Furthermore, in the L-shaped joint 60 of this embodiment, a disk-shaped base flange 63 is provided coaxially with the vertical pipe 61 above the horizontal pipe 62, and an annular fixed flange 65 is provided at approximately the same height and spaced apart radially outward from the base flange 63. The fixed flange 65 is disposed so as to surround the outer periphery of a plurality of U-shaped arms 66, and is integrated with the base flange 63 via the plurality of U-shaped arms 66.

[0025] In the L-joint 60 of this embodiment, the fixed flange 65, the base flange 63 and the displacement absorbing section 66 are made of an elastic material (rubber, elastomer, resin) that can be molded as one piece, and are integrally formed by two-color molding. In this embodiment, the base flange 63 is disposed between the U-shaped arm 66 and the vertical pipe 61, and the multiple U-shaped arms 66 are disposed in each direction that is evenly spaced in the circumferential direction of the vertical pipe 61.

[0026] In this embodiment, the U-shaped arm 66 has a base side arm 67 connected to the base flange 63 side, a U-shaped portion 68, and a fixed side arm 69 connected to the fixed flange 65 side, and the fixed side arm 69 connected to the fixed flange 65 side is longer than the base side arm 67. In the intended mounting position (see FIG. 2), the fixing flange 65 is fitted into the accommodation recesses 21, 25 at six points on the floor plate 20 side of the battery case 9. In this embodiment, the outer shape of the portion of the fixing flange 65 to be fixed is circular. Furthermore, the thickness of the U-shaped arm 66 and the base flange 63 is thinner than the thickness of the fixing flange 65, and a step is provided in the Z direction.

[0027] A plurality of U-shaped arms 66 are provided between the base flange 63 and the fixed flange 65. The plurality of U-shaped arms 66 are displacement absorbing parts interposed to allow radial movement of the fixed flange 65 relative to the base flange 63. The base flange 63 of this embodiment has a plurality of exhaust ports 64 formed therethrough in the up-down direction and equidistantly spaced in the circumferential direction.

[0028] [Fixed cover] Of the fixed covers 30, 40, the central fixed cover 40 has a thick base 45 in the center, with fixing screw holes 44 provided in two appropriate locations on the base 45, as shown in Fig. 6. Two convex semicircular cover face plates 41 are integrally formed at both ends of the base 45 so as to protrude laterally in the longitudinal direction. A vertical pipe insertion hole 42 is formed through each of the cover face plates 41 coaxially with the center of the arc. A concave semicircular flange guide 43 is formed on the inner surface (center of the back surface) of the thick portion of the base 45.

[0029] As shown in Fig. 7, of the fixed covers 30, 40, the end fixed cover 30 has a thick base 35 at one end, and a fixing screw hole 34 is provided at one appropriate position on the base 35. A convex semicircular cover panel 31 is integrally formed so as to protrude from one end of the base 35. A vertical pipe insertion hole 32 is formed coaxially with the center of the arc of the cover panel 31. A concave semicircular flange guide 33 is formed on the inner surface (central part of the back surface) of the thick part of the base 35.

[0030] [Pipe connections and recesses] 2 and 3(a), the central accommodation recess 25 at the front and rear of the center of the floor plate 20 is formed with a central connecting pipe accommodation groove 26 for accommodating the central connecting pipe 3, and further, a flange guide groove 27 and a fixed cover fitting groove 28 are formed in multiple steps by recessed stepped portions. Also, fixing screw holes 29 are screwed in at appropriate positions so that the fixing screws 8 can be screwed in. The two L-shaped joints 60 are connected to each other via the central connecting pipe 3, and are fitted so as to face the left and right sides of the accommodation recess 25. At this time, the outer peripheral surface of the fixed flange 65 is fitted in a state in which it can rotate in the circumferential direction relative to the inner peripheral surface of the flange guide groove 27. The central fixed cover 40 has the convex semicircular arcs on both ends of the cover face plate 41 exactly accommodated in the fixed cover fitting groove 28, and in this state, the central fixed cover 40 is used to clamp and restrain the fixed flange 65 from above. Then, the central fixed cover 40 is fixed by fixing screws 8, and then, in this state, each battery module 10 is placed and fixed to the vertical tube 61 of each L-shaped joint 60, with gaskets 6 interposed as sealing members on the upper surface of the central fixed cover 40.

[0031] 2, 3(b), and 8, the left and right end accommodating recesses 21 on the front side of the floor plate 20 are formed with end connecting pipe accommodating grooves 22 for accommodating the end connecting pipes 2, and further, the flange guide grooves 23 and the fixed cover fitting grooves 24 are formed in multiple steps by recessed stepped portions. Also, fixing screw holes 29 are threadedly provided in appropriate positions so that the fixing screws 8 can be screwed in. The left and right T-joints 50 are fitted into the accommodation recess 21 in a state where the water supply pipe 4 or the drain pipe 5 and the end connecting pipe 2 are connected therethrough. At that time, the outer peripheral surface of the fixed flange 55 is fitted into the flange guide groove 23 in a state where it can rotate in the circumferential direction relative to the inner peripheral surface of the flange guide groove 23. The end fixing cover 30 has the convex semicircular arc of the cover face plate 31 exactly accommodated in the fixed cover fitting groove 24, and in this state, the end fixing cover 30 is used to clamp and restrain the fixed flange 55 from above. Then, the end fixing cover 30 is fixed by the fixing screws 8, and then, in this state, each battery module 10 is placed and fixed to the vertical pipe 51 of each T-shaped joint 50, with gasket 6 interposed as a sealing member on the upper surface of the end fixing cover 30.

[0032] 2 and 9, the left and right end accommodating recesses 21 on the rear side of the floor plate 20 are formed with end connecting pipe accommodating grooves 22 that accommodate the end connecting pipes 2 and are connected along the front-rear direction, and further, the flange guide grooves 23 and the fixed cover fitting grooves 24 are formed in multiple steps by recessed stepped portions. Also, fixing screw holes 29 are screwed in at appropriate positions so that the fixing screws 8 can be screwed in. The horizontal pipes 62 of the left and right rear L-shaped joints 60 are connected to the rear ends of the end connecting pipes 2 accommodated in the end connecting pipe accommodating grooves 22, and are fitted into the left and right end accommodating recesses 21 on the rear side of the floor plate 20. At that time, the outer peripheral surface of the fixed flange 65 is fitted into the inner peripheral surface of the flange guide groove 23 in a state in which it can rotate circumferentially. The convex semicircular arc of the cover face plate 31 of the end fixing cover 30 is exactly received in the fixed cover fitting groove 24, and in this state, the end fixing cover 30 is used to clamp and restrain the fixed flange 65 from above. The end fixing cover 30 is then fixed in place with the fixing screws 8, and thereafter, in this state, each battery module 10 is placed and fixed to the vertical tube 61 of each L-shaped joint 60, with packing 6 interposed as a sealing member on the upper surface of the end fixing cover 30.

[0033] [Effects] Next, a description will be given of the functions and effects of the pipe joints 50, 60 of this embodiment. In the following, when there is no particular need to distinguish between the T-shaped joint 50 and the L-shaped joint 60, they will be referred to as the pipe joints 50, 60 (the same applies to the detailed reference numerals). As described above, the pipe joints 50, 60 of the present embodiment are used in the cooling pipes of the assembled battery 1 including the battery module 10 and the battery case 9. Here, in order to improve the ease of assembly of the cooling pipes, if the battery module 10 is placed and fixed on the floor plate 20 of the battery case 9 and then the pipe joints are fitted into the cooling pipes, there is a problem that the piping work is performed from below the floor plate 20, which deteriorates the workability of the piping work. Therefore, it is desirable to install the cooling pipes and the pipe joints 50, 60 on the floor plate 20 of the battery case 9 in advance to improve the workability of assembling the cooling pipes.

[0034] That is, in this embodiment, as shown in Figures 4 and 5, the piping fittings 50, 60 include vertical pipes 51, 61 connected to the cooling piping on the battery module 10 side, horizontal pipes 52, 62 communicating with the vertical pipes 51, 61 and connected to the cooling piping on the floor plate 20 side of the battery case 9, base flanges 53, 63 arranged coaxially with the vertical pipes 51, 61 above the horizontal pipes 52, 62, fixed flanges 55, 65 arranged radially outside the base flanges 53, 63 and fitted into the accommodating recesses 21, 25 on the floor plate 20 side, and displacement absorbing portions 56, 66 arranged between the base flanges 53, 63 and the fixed flanges 55, 65 and interposed so as to allow radial movement of the fixed flanges 55, 65 relative to the base flanges 53, 63.

[0035] According to the pipe joints 50, 60 of this embodiment, the displacement absorbing parts 56, 66 are unloaded before the fixing flanges 55, 65 are attached to the accommodation recesses 21, 25 on the floor plate 20 side. Therefore, the only positional variation is the dimensional tolerance, and the radial positional deviation of the pipe joints 50, 60 caused by backlash or reaction force can be absorbed by the displacement absorbing parts 56, 66. Therefore, the induction of the cooling pipes 2, 3, 4, 5 to be connected can be reduced, improving the ease of assembly and contributing to space saving [Invention 1].

[0036] In particular, in the pipe fittings 50, 60 of this embodiment, as shown in Figures 4 and 5, the displacement absorbing parts 56, 66 are arranged at equal intervals in the circumferential direction of the base flanges 53, 63. This allows the multiple displacement absorbing parts 56, 66 to bend and deform individually in the XY plane directions, which is preferable as a configuration that allows the fixed flanges 55, 65 to move individually in the radial direction relative to the base flanges 53, 63 and is freely movable in the XY plane directions [Invention 2].

[0037] In the pipe joints 50, 60 of this embodiment, the thickness of the displacement absorbing parts 56, 66 and the thickness of the base flanges 53, 63 are thinner than the thickness of the fixed flanges 55, 65. As a result, in the pipe joints 50, 60 of this embodiment, the fixed flanges 55, 65 protect the displacement absorbing parts 56, 66 during assembly. This is preferable for preventing damage to the displacement absorbing parts 56, 66 and improving the assembly of the pipe joints 50, 60, and is preferable as a configuration that allows free movement in the XY plane directions because no friction occurs between the displacement absorbing parts 56, 66 and the base flanges 53, 63 and the floor plate 20 side [Invention 3].

[0038] 8 and 9, in the pipe fittings 50, 60 of this embodiment, the fixing flanges 55, 65 are sandwiched between the fixing covers 30, 40 for fixing the fitting and the accommodating recesses 21, 25 of the floor plate 20 so as to receive the load of the fixing flanges 55, 65 in the Z direction. As a result, according to the pipe fittings 50, 60 of this embodiment, when the battery module 10 is inserted or removed (axial seal pressure), no load is applied directly to the displacement absorbing parts 56, 66, and damage to the displacement absorbing parts 56, 66 can be prevented or suppressed in advance [Invention 4].

[0039] In this type of battery pack, in order to prevent a short circuit in the event of a malfunction, it is desirable to locate the cooling piping as far as possible on the outside of the battery case 9 in order to prevent cooling water from entering the battery case in the event of a malfunction in the seal or cooling piping. Even if the cooling piping is located inside the battery case 9, it is desirable to provide a mechanism that can discharge cooling water outside the battery case. In contrast, in the pipe joints 50, 60 of this embodiment, as shown in Figures 4 and 5, the base flanges 53, 63 are provided with cooling water outlets 54, 64. Therefore, according to the pipe joints 50, 60 of this embodiment, the cooling water can freely fall from the outlets 54, 64 to the floor plate 20 side. Therefore, even if water leakage occurs due to a failure of the shaft seal, the cooling water can be efficiently discharged from the outlets 54, 64 to the outside of the battery case 9 [Invention 5].

[0040] 8 and 9, the accommodation recesses 21, 25 on the floor plate 20 side are provided with connecting pipe accommodation grooves 22, 26 at positions facing the base flanges 53, 63 to function as drainage holes penetrating to the outside, and the size of the connecting pipe accommodation grooves 22, 26, which also function as drainage holes at positions facing the base flanges 53, 63, is smaller than the outer diameter of the base flanges 53, 63 and can have a larger opening area than the opening area of ​​the outlets 54, 64 (see FIG. 8(c)). Such a configuration is more suitable for discharging cooling water from the outlets 54, 64 to the outside of the battery case 9 [Invention 6].

[0041] 4 and 5, in the pipe fittings 50, 60 of this embodiment, the displacement absorbing parts 56, 66 have U-shaped arms connecting the inner circumferential surface of the fixed flanges 55, 65 and the outer circumferential surface of the base flanges 53, 63 at both ends, and the arm of the U-shaped arm on the fixed flange 55, 65 side is longer than the arm on the base flange 53, 63 side. As a result, according to the pipe fittings 50, 60 of this embodiment, the reaction force of the displacement absorbing parts 56, 66 is reduced and no load is applied to the shaft seal when inserting or removing the battery module 10, thereby further improving the ease of assembly [Invention 7].

[0042] 8 and 9, in the pipe fittings 50, 60 of this embodiment, the inner peripheral shape of the accommodating recesses 21, 25 and the outer peripheral shape of the fixed flanges 55, 65 are both circular, and the fixed flanges 55, 65 are rotatably accommodated along the circumferential direction of the accommodating recesses 21, 25. As a result, according to the pipe fittings 50, 60 of this embodiment, the fixed flanges 55, 65 can be rotated in the XY plane along the circumferential direction of the accommodating recesses 21, 25 while being positioned radially, so that when the pipe fittings 50, 60 are assembled, positional deviations due to the influence of hose bends in the cooling pipes 2, 3, 4, 5 can be absorbed without load. In particular, in the pipe fittings 50, 60 of this embodiment, the parts other than the fixed flanges 55, 65 are not fixed by the fixed covers 30, 40, which are lids for fixing the fitting. Therefore, even after the fixed covers 30, 40 are attached, the parts other than the fixed flanges 55, 65 are positioned in the direction perpendicular to the axis, but are held movable in the direction to relieve the load, so that the effects of tolerances, etc. can be absorbed more effectively [Invention 8].

[0043] In the pipe joints 50 and 60 of this embodiment, as shown in Figures 4 and 5, the fixed flanges 55 and 65, the base flanges 53 and 63, and the displacement absorbing parts 56 and 66 are made of an elastic material that can be molded as one piece, and the displacement absorbing parts 56 and 66 are integrally formed by two-color molding. As a result, the pipe joints 50 and 60 of this embodiment can expand the change in reaction force of the displacement absorbing parts 56 and 66 and the range of the reaction force of the displacement absorbing parts 56 and 66. In addition, if an inexpensive elastic material is used, costs can be reduced [Invention 9].

[0044] As described above, according to the battery pack pipe joints 50, 60 of this embodiment, the pipe connection portion can be configured compactly, while the assembly workability of the cooling pipes at the pipe connection portion can be improved. Incidentally, the battery pack pipe joint according to the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications are possible without departing from the spirit of the present invention. [Explanation of symbols]

[0045] 1 battery pack 2 End connection pipe (cooling pipe) 3 Central connecting pipe (cooling pipe) 4 Water supply pipe (cooling pipe) 5 Drain pipe (cooling pipe) 6. Packing 8 Fixing screw 9 Battery case 10 Battery module 11 Heat exchanger 12 Water supply and drainage outlet (cooling pipes) 20 Floor Plate 21 End receiving recess 22 End connection pipe accommodation groove 23 Flange guide groove 24 Fixed cover fitting groove 25 Central storage recess 26 Central connecting pipe receiving groove 27 Flange guide groove 28 Fixed cover fitting groove 29 Fixing screw hole 30 End fixing cover 31 Cover panel 32 Vertical pipe insertion hole 33 Flange Guide 34 Fixing screw hole 35 Base 40 Center fixed cover 41 Cover panel 42 Vertical pipe insertion hole 43 Flange Guide 44 Fixing screw hole 45 Base 50 T-type fitting (piping fitting) 51 Vertical pipe 52 Horizontal pipe 53 Base flange 54 Outlet 55 Fixed flange 56 Displacement absorbing section (U-shaped arm) 57 Proximal arm 58 U-shaped part 59 Fixed side arm 60 L-type joint (piping joint) 61 Vertical Pipe 62 Horizontal pipe 63 Base flange 64 discharge ports 65 fixing flange 66 displacement absorption part (U-shaped arm) 67 base side arm 68 U-shaped part 69 fixing side arm

Claims

1. A piping joint used for cooling piping of a battery pack including a battery case and a battery module housed in the battery case and placed on a floor plate of the battery case, a vertical pipe connected to the cooling piping on the battery module side; a horizontal pipe communicating with the vertical pipe and connected to the cooling piping on the floor plate side; a fixing flange provided on a radially outer side of the vertical pipe and spaced apart therefrom, the fixing flange being fitted in the receiving recess on the floor plate side so as to be rotatable in a circumferential direction; a displacement absorbing portion provided between the vertical pipe and the fixed flange and capable of allowing radial movement of the fixed flange relative to the vertical pipe; A piping joint for a battery pack comprising:

2. A base flange is provided above the horizontal pipe and coaxially with the vertical pipe, 2. The pipe joint for a battery assembly according to claim 1, wherein the displacement absorbing portion comprises a plurality of elastic deformation portions that are equally spaced apart in a circumferential direction of the base flange.

3. A base flange is provided above the horizontal pipe and coaxially with the vertical pipe, 2. The pipe joint for a battery pack according to claim 1, wherein a thickness of the displacement absorbing portion and a thickness of the base flange are smaller than a thickness of the fixing flange.

4. 2. The battery pack pipe fitting according to claim 1, wherein the fixing flange is sandwiched between a fixing cover that covers the battery pack pipe fitting from above and the accommodating recess on the floor plate side, and portions other than the fixing flange are not fixed to the floor plate, and the load of the battery pack pipe fitting is supported by the floor plate only by the fixing flange.

5. A base flange is provided above the horizontal pipe and coaxially with the vertical pipe, 2. The battery pack pipe joint according to claim 1, wherein the base flange is provided with a drain port for cooling water in case of leakage of the cooling water.

6. The accommodation recess on the floor plate side is provided with a drain hole penetrating to the outside at a position facing the base flange, 6. The piping joint for a battery assembly according to claim 5, wherein the drain hole at a position facing the base flange has a diameter smaller than an outer diameter of the base flange and an opening area larger than an opening area of ​​the exhaust port.

7. A base flange is provided above the horizontal pipe and coaxially with the vertical pipe, the displacement absorbing portion has U-shaped arms connecting, at both ends, an inner circumferential surface of the fixing flange and an outer circumferential surface of the base flange, 2. The pipe joint for a battery assembly according to claim 1, wherein the arm of the U-shape connected to the fixing flange side is longer than the arm connected to the base flange side, with the U-shape being the boundary.

8. 2. The pipe joint for a battery pack according to claim 1, wherein an inner circumferential shape of the accommodating recess and an outer circumferential shape of the fixing flange are both circular and of the same diameter, and the fixing flange is accommodated within the accommodating recess so as to be rotatable along a circumferential direction of the accommodating recess.

9. 3. The piping joint for a battery pack according to claim 2, wherein the fixing flange, the base flange and the displacement absorbing portion are made of an elastic material that can be molded as an integral unit.

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