Heat transport device and method for manufacturing heat transport device

Abstract

An object of the present invention is to provide a heat transport device in which a plurality of extruded multi-hole tubes are connected to each other by coupling and bolt fastening, the number of manufacturing steps is small, the flatness of a heat input surface is high, and the contact thermal resistance with a heating element is low.SOLUTION: A heat transport device of the present example embodiment includes a plurality of pipeline bodies in which a plurality of flow paths through which a refrigerant passes are provided in a longitudinal direction thereof, and a notch portion which is formed at an end portion in a direction orthogonal to the longitudinal direction of the pipeline body and is fitted to an end portion of an adjacent pipeline body, and the plurality of pipeline bodies are formed to be one plane by fitting and connecting the notch portions to each other.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] SUMMARY OF THE INVENTION Embodiments of the present invention relate to heat transport devices and methods for manufacturing heat transport devices. [Background technology]

[0002] In railway and infrastructure applications, assembled batteries containing battery cells are packed together and arranged densely in a limited space. To cool an assembled battery containing a large number of heat-generating battery cells, one method is to install a heat transport device with a flow path for refrigerant on the bottom of the assembled battery, which cools the assembled battery and also manages the temperature of the battery cells inside the assembled battery.

[0003] A heat transport device having a flow path for a refrigerant has a battery pack containing a large number of battery cells, which are heat-generating bodies, placed on top of it, so the top surface is flat and the dimensions are large.

[0004] When manufacturing such a large, flat heat transport device from a single plate, one method is to join the flow path formed as an extruded tube using a large press to the lid by welding, FSW (friction stir welding), or brazing.

[0005] One issue with using FSW is that milling machining is required to correct distortion and warping on the joining surface and achieve the desired flatness, which increases the number of steps. Also, if warping occurs, when using an extruded pipe as the heat input part, the warping increases the contact thermal resistance and reduces cooling performance. Another issue is that since it is assumed that the heat transport device will be placed on the FSW machine, there are dimensional restrictions on the machine table, and it cannot be used if the required width of the heat transport device exceeds the dimensions of the machine table. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2023-149110 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem that this invention aims to solve is to provide a heat transport device that requires less manufacturing time, has a high flatness of the heat input surface, and has low contact thermal resistance with the heat-generating body, by arranging and connecting multiple extruded perforated pipes and fastening them with bolts. [Means for solving the problem]

[0008] The heat transport device of this embodiment is formed by a plurality of pipe lines, each having a plurality of flow paths for passing a refrigerant therethrough along its longitudinal direction, and cutout portions formed at the ends of the pipe lines perpendicular to the longitudinal direction, which fit into the ends of adjacent pipe lines, and the cutout portions are fitted and connected together to form a single plane for the plurality of pipe lines. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view showing a storage battery device according to an embodiment. [Figure 2] FIG. 2 is a perspective view showing the heat transport device according to the embodiment. [Figure 3] FIG. 3 is a diagram showing a heat transport device provided with a connecting member. [Figure 4] FIG. 4 is a perspective view showing the connection member. [Figure 5] FIG. 5 is a cross-sectional view of the heat transport device as seen from the direction of the flow path. DETAILED DESCRIPTION OF THE INVENTION

[0010] A heat transport device for carrying out the invention will be described below with reference to FIGS.

[0011] Fig. 1 is a perspective view showing a storage battery device 1 according to an embodiment. Fig. 2 is a perspective view showing a heat transport device 10 according to an embodiment.

[0012] As shown in FIG. 1, the storage battery equipment 1 includes a plurality of battery packs 100 and a heat transport device 10 provided on the bottom surface of the battery packs 100.

[0013] The storage battery device 1 is mounted on a railway vehicle or the like and is used as a power source for driving an electric motor (not shown).

[0014] The battery pack 100 is arranged in 3 rows and 2 columns as shown in Fig. 1. The battery pack 100 is equipped with multiple cells connected in series and parallel to obtain the desired voltage and current, and also contains voltage and temperature monitoring and protection circuits (not shown).

[0015] The cell is, for example, a non-aqueous electrolyte secondary battery such as a lithium ion battery, and includes a flat or approximately rectangular outer container made of aluminum or an aluminum alloy, and a power generating element (not shown) housed in the outer container together with a non-aqueous electrolyte.

[0016] In the battery pack 100, cell outer containers are densely arranged in a limited space, which traps heat and causes the temperature to rise. To cool the battery pack 100, a heat transport device 10 (also called a heat sink) is provided on the underside of the battery pack 100.

[0017] The battery pack 100 has holes at its four corners through which bolts (not shown) are passed, and is fixed to the heat transport device 10 by attaching connectors 21 such as bolts to the bolt holes.

[0018] The heat transport device 10 is formed by connecting a plurality of pipe bodies 12. As shown in Fig. 2, the plurality of pipe bodies 12 have a plurality of flow paths 13 for passing a refrigerant therethrough in the longitudinal direction (hereinafter, the direction in which the cooling medium flows is referred to as the longitudinal direction). In Fig. 2, each pipe body 12 has five flow paths 13, but this number is not necessarily five.

[0019] The multiple conduit bodies 12 are made of extruded perforated pipes. Extruded perforated pipes are formed, for example, by placing heated metal material in an extruder using a dedicated extrusion die with the desired flow path shape and forcing it into the die under pressure. The metal material is an aluminum billet or the like. The extruder forms a long pipe shape in the longitudinal direction, which can be cut to the desired length after forming.

[0020] As shown in FIG. 2, a total of six pipe line bodies 12 are provided adjacent to each other, but this does not necessarily have to be six. This is determined by the number of battery packs 100 to be installed in the heat transport device 10. Cutout portions 16 are provided at the short-side ends (ends perpendicular to the longitudinal direction) of the multiple pipe line bodies 12. The cutout portions 16 are formed by fitting the convex portions and concave portions of the cutout portion 16 at the end of one pipe line body 12 of adjacent pipe line bodies 12 with the cutout portion 16 at the end of the other pipe line body 12, thereby connecting the multiple pipe line bodies 12 so that they form a single plane. The connection method will be described in detail later using FIG. 5.

[0021] The heat transport device 10 also has holes 20 through which connectors 21 such as bolts are inserted at the four corners of the battery pack 100 .

[0022] Next, a heat transport device 10 provided with a connecting member 14 that connects the flow paths 13 of adjacent duct bodies 12 will be described with reference to FIGS.

[0023] 3 is a diagram showing the heat transport device 10 provided with the connecting member 14. FIG. 4 is a perspective view showing the connecting member 14.

[0024] The connecting members 14 are provided at the longitudinal ends of the multiple pipe bodies 12, and are provided to connect the flow paths 13 of one pipe body 12 to the flow paths 13 of the other pipe body 12. In FIG. 3, the connecting members 14 are provided to connect the ends of two pipe bodies 12, but depending on the size of the battery pack 100, three or more pipe bodies 12 may be used. When three pipe bodies 12 are connected, the flow paths of one pipe body 12 are connected to the flow paths of two pipe bodies 12. The connecting members 14 are made of a material such as resin.

[0025] At the longitudinal end of the pipeline body 12, holes 26 for fixing the connecting members 14 are provided along the longitudinal direction of the pipeline body 12. By fixing the connecting members 14 along the longitudinal direction, the pipeline body 12 and the connecting members 14 are fastened together. The connecting members 14 are fixed to the holes 26 by connectors 27, which are, for example, self-tapping bolts. The holes 26 may be formed by punching a mold designed and manufactured in advance as an extrusion die, and a plurality of holes may be formed therein.

[0026] As shown in Fig. 3, the end of a set of pipe bodies 12 is provided with a recess 15 for attaching a connecting member 14 to the set of pipe bodies 12. Although the recess 15 is formed in a curved shape in Fig. 3, it may also be straight or have an angle. It is preferable to cut the recess 15 before connecting the set of pipe bodies, but it may also be cut and formed after connecting the set of pipe bodies.

[0027] 3 and 4, the connecting member 14 has a recess 17 formed therein so as to cover all four sides of the end of the longitudinal direction of the conduit body 12. The connecting member 14 is provided at a position on the conduit body 12 that includes a notch 16 formed at the end in a direction perpendicular to the longitudinal direction of the conduit body 12. As a result, when the connecting member 14 is attached to the conduit body 12, the end of the conduit body 12 is positioned within the recess 17 of the connecting member 14.

[0028] The pipe body 12 is designed so that when the refrigerant flows from the end of the pipe body 12 to the inlet and outlet of the connecting member 14, there is no gap between the connecting member 14 and the pipe body 12. In addition, an O-ring, gasket, rubber sealant, or the like that prevents refrigerant leakage is interposed between the connecting member 14 and the end of the pipe body 12 that is surrounded by the connecting member 14, so that the refrigerant does not leak from between the pipe body 12 and the connecting member 14.

[0029] Furthermore, a hole 28 is provided so as to penetrate the connecting member 14 in a direction perpendicular to the longitudinal direction of the connecting member 14. The position of this hole 28 must coincide with the position of a hole 29 shown in Fig. 3 formed in the conduit body 12. The hole 29 for joining the connecting member 14 may be provided by additional processing after the conduit body 12 is formed.

[0030] Next, a method for connecting a plurality of duct members 12 will be described with reference to Fig. 5. Fig. 5 is a cross-sectional view of the duct members 12 of the heat transport device 10 as viewed from the direction of the flow paths.

[0031] Cutouts 16 are provided at the ends of the shorter sides of the multiple pipe bodies 12 (ends in the direction perpendicular to the longitudinal direction). As shown in Fig. 5, when two pipe bodies 12 are arranged side by side, the convex portion and concave portion of the cutout 16 at the end of one pipe body 12 fit together, so that the multiple adjacent pipe bodies 12 form a single plane. By fitting and fixing the cutouts 16 of the multiple pipe bodies 12 together, the heat transport device 10 to which the multiple pipe bodies 12 are connected is formed to form a single plane.

[0032] The cutout portion 16 is formed and manufactured in advance by designing an extrusion die so that the protrusion and the recess fit together.

[0033] As shown in Fig. 5, connectors 18 (not shown) made of bolts and nuts are fastened by passing through holes 22 and 23 in a direction perpendicular to the pipeline body 12 with the cutout portions 16 fitted together. As long as the connectors 18 are fixed in place with the cutout portions 16 fitted together, they may protrude from the lower cutout. From the perspective of minimizing the number of connectors 18, it is desirable to additionally machine the holes 22 and 23 into the pipeline body 12 so that the fitted portions of the cutout portions 16 are alternately provided.

[0034] 5(a) is a cross-sectional view in which the notch 16 at the end of the pipe body 12 in the direction perpendicular to the longitudinal direction is not cut. Even if the notch 16 is not cut, the notch 16 fits into the recess of the connecting member 14, and the pipe body 12 is connected to the inlet and outlet of the connecting member 14, so there is no risk of refrigerant leakage.

[0035] 5(b) shows a modified example of both ends in a direction perpendicular to the longitudinal direction of the pipeline body 12. Since both ends in a direction perpendicular to the longitudinal direction of the pipeline body 12 do not need to be connected to adjacent pipeline bodies 12, it is not necessary to form the notch portions 16.

[0036] 5(c) shows an example in which the cutout portions 16 are cut along the dashed lines 30 to make the cross sections uniform. In this case, holes 26 are required for threading in the longitudinal direction to fix the connecting members 14. For this reason, the number of flow paths 13 in the conduit body 12 may be reduced from five to four, and holes 26 for fixing the connecting members 14 may be formed in the portions of the reduced flow paths 13. Furthermore, the number of flow paths 13 is not limited to four.

[0037] In the case of FIG. 5(b), the number of dies for forming the extruded perforated pipe for manufacturing the pipeline body 12 is increased.

[0038] A connector 18 (not shown), which is made of a bolt and nut, penetrates and connects the portion into which the cutout portion 16 is fitted. When the connector 18 is used to secure the portion into which the cutout portion 16 is fitted, a recess is formed in advance by countersinking the portion of the pipe body 12 where the connector 18 is to be provided so that the end of the connector 18 does not protrude from the surface of the pipe body 12. Specifically, the connector 18 is formed so that the head of the bolt and the tip of the nut do not protrude from the surface of the pipe body 12. Since the end of the connector 18 does not protrude from the surface of the pipe body 12, the battery pack 100 is in close contact with the heat transport device 10, reducing the contact thermal resistance acting on the surface, and heat from the battery pack 100 transfers to the heat transport device 10 without resistance.

[0039] The connecting member 14 connects one pipe body 12 to the other pipe body 12, so that the refrigerant flowing from one pipe body 12 passes through the connecting member 14 and flows into the other pipe body 12. As a result, the inflow and outflow of the refrigerant to the pipe body 12 can be concentrated at one end of the pipe body 12, which simplifies the configuration of the cooling device for the battery pack 100. Furthermore, since the refrigerant receives heat from the battery pack 100 by passing through the pipe body 12 in this way, and as a result cools the battery pack 100, the maximum current can be passed through the battery pack 100.

[0040] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0041] 1. Battery storage device 10 Heat transport device 12 Pipe body 13 Flow path 14 Connecting member 15 Relief 16 Cutout 17 Recess 18, 27 Connectors 22, 23 bolt holes 100 battery packs

Claims

1. a plurality of piping bodies each having a plurality of flow paths for passing a refrigerant therethrough, the flow paths being arranged in the longitudinal direction of the piping bodies; a notch formed at an end of the pipe body in a direction perpendicular to the longitudinal direction, the notch being adapted to fit into an end of an adjacent pipe body; The cutout portions are fitted together and connected to form a plurality of pipe bodies in a single plane. Heat transport device.

2. The fitting portions of the cutout portions of the pipeline body are fixed with a connector. The heat transport device according to claim 1.

3. The fitting portions of the cutout portions of the pipeline body are fixed by the connectors that pass through the cutout portions, The end of the connector is formed so as not to protrude from the surface of the pipe body. The heat transport device according to claim 2.

4. a connecting member provided at each end of the plurality of pipe bodies in the longitudinal direction, the connecting member connecting a flow path of one of the pipe bodies to a flow path of another adjacent pipe body; The heat transport device according to claim 1.

5. a hole for fixing the connecting member is provided along the longitudinal direction of the pipe body at an end portion in the longitudinal direction of the pipe body, and the connecting member is fixed to the hole; The heat transport device according to claim 4.

6. The connecting member is provided so as to cover four sides of the end of the conduit body, and a recess for attaching the connecting member is provided at the end of the cutout portion of the conduit body. The heat transport device according to claim 4 or 5.

7. a conduit body having a plurality of flow paths for passing a refrigerant therethrough in the longitudinal direction thereof, and having cutout portions formed at ends perpendicular to the longitudinal direction thereof, the cutout portions being fitted with ends of adjacent conduit bodies, the cutout portions being fitted with each other; The positions where the cutout portions are fitted together are fixed by a connector, so that the plurality of pipe bodies are formed in a single plane. A method for manufacturing a heat transport device.

8. The pipe body is molded by forcing a heated metal material into an extrusion die that has the shape of the flow path. The method for manufacturing the heat transport device according to claim 7 .

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