Vehicle manufacturing method

Abstract

To provide a vehicle manufacturing method that is capable of suppressing decrease in axial force of fastening members and securing a space required for setting components.SOLUTION: A vehicle manufacturing method includes a cooling step, a heating step, an assembling step and a fastening step. In the cooling step, a rear module 18 is cooled whereby a clearance in a vehicle width direction of a pair of right and left rear side members 40 decreases according to contraction. Further, in the heating step, a battery frame 28 is heated whereby a clearance in the vehicle width direction of a pair of right and left side frames 30 is increased according to expansion. Accordingly, a space is provided between both components, thereby allowing both components to be set. Then, in the fastening step, both components are fastened in a state that the pair of right and left rear side members 40 and the pair of right and left side frames 30 hold approximately the same temperature. In this way, the space reduces when both components are held at approximately the same temperature. Decrease in axial force of fastening bolts is suppressed by fastening in this state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle manufacturing method. [Background technology]

[0002] For example, Patent Document 1 listed below discloses a structure in which a side sill is attached to a rear frame from the outside in the vehicle width direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-151482 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, if the left and right rear frames are molded as a single unit (rear module) and the left and right side sills are molded as a single unit (center module), and the rear module and center module are fastened together with fastening bolts, it is necessary to eliminate any gap between them to avoid a decrease in the axial force of the fastening bolts (fastening members). On the other hand, a gap is required between the two parts in order to set them together. In other words, with regard to gaps, bolt fastening and part setting are mutually exclusive, making it difficult to achieve both.

[0005] In consideration of the above, the present invention aims to provide a vehicle manufacturing method that can ensure the gap necessary for setting parts and suppress the reduction in axial force of fastening members due to the gap. [Means for solving the problem]

[0006] The vehicle manufacturing method of claim 1 is a vehicle manufacturing method for a vehicle skeleton structure including: a battery frame arranged under the vehicle, supporting a battery pack, and including a pair of left and right side frames arranged on both outer sides in the vehicle width direction, the pair of left and right side frames being integrated together; and a skeleton member arranged at least in one of the front and rear of the vehicle, and including a pair of left and right side members extending in the fore-and-aft direction of the vehicle, the pair of left and right side members being integrated together, the method including a cooling process for cooling at least the pair of left and right side members; a heating process for heating at least the pair of left and right side frames; an assembling process for assembling the pair of left and right side members to the inner sides of the pair of left and right frames in the vehicle width direction while the pair of left and right side members and the pair of left and right side frames are maintained at different temperatures; and a fastening process for fastening the pair of left and right side frames to the pair of left and right side members while the pair of left and right side members and the pair of left and right side frames are maintained at approximately the same temperature.

[0007] The vehicle manufacturing method according to claim 1 is a method for manufacturing a vehicle having a vehicle skeleton structure including a battery frame and a skeleton member disposed at least at one of the front and rear of the vehicle, and includes a cooling process, a heating process, an assembly process, and a fastening process.

[0008] The battery frame is disposed under the vehicle, supports the battery pack, and includes a pair of left and right side frames on both outer sides in the vehicle width direction. The pair of left and right side frames are integrated. Meanwhile, a framework member is disposed in at least one of the front and rear of the vehicle, and the framework member includes a pair of left and right side members extending in the fore-and-aft direction of the vehicle, and the pair of left and right side members are integrated.

[0009] For this reason, in the present invention, a pair of left and right side frames that form part of the battery frame and a pair of left and right side members that form part of a skeletal member arranged at least in one of the front and rear of the vehicle are fastened together.

[0010] In this way, in the present invention, before the pair of left and right side frames of the battery frame and the pair of left and right side members of the framework member are fastened together, the cooling process, heating process, and assembly process are performed. Note that the cooling process and heating process can be performed in any order, as they are performed on different members.

[0011] In the cooling step, at least the pair of left and right side members of the frame member are cooled, causing the pair of left and right side members of the frame member to contract and reducing the distance between them in the left-right direction (vehicle width direction).

[0012] In the heating step, at least a pair of left and right side frames of the battery frame are heated, causing the pair of left and right side frames of the battery frame to expand and increasing the distance between them in the left-right direction (vehicle width direction).

[0013] Then, in the assembly process, the pair of left and right side members are set (assembled) inside the pair of left and right frames in the vehicle width direction while the pair of left and right side members and the pair of left and right side frames are maintained at different temperatures.

[0014] The cooling process described above causes the pair of left and right side members of the framework member to shrink, reducing the separation distance in the vehicle width direction. The heating process also causes the pair of left and right side frames of the battery frame to expand, increasing the separation distance in the vehicle width direction.

[0015] This allows a gap to be provided between the pair of left and right side members of the framework member and the pair of left and right side frames of the battery frame, which makes it possible to position the pair of left and right side members on the inner side of the pair of left and right frames in the vehicle width direction, allowing each part to be set (assembled).

[0016] Next, in the fastening process, the pair of left and right side members and the pair of left and right side frames are fastened together while the pair of left and right side frames are maintained at approximately the same temperature. In this manner, a vehicle is manufactured.

[0017] By bringing the pair of left and right side members and the pair of left and right side frames to approximately the same temperature, the pair of left and right side members of the skeletal member that contracted during the cooling process and the pair of left and right side frames of the battery frame that expanded during the heating process return to their original dimensions.

[0018] This reduces the gap between the pair of left and right side members of the skeletal member and the pair of left and right side frames of the battery frame, and by fastening the two together in this state with fastening members such as fastening bolts, it is possible to suppress the reduction in axial force of the fastening members due to the formation of the gap.

[0019] Therefore, the present invention makes it possible to ensure the gaps necessary to set the pair of left and right side members on the inner sides of the pair of left and right side frames in the vehicle width direction, while suppressing a decrease in the axial force of the fastening members due to the formation of the gaps. In other words, the present invention makes it possible to achieve the contradictory goals of ensuring the gaps necessary to set the parts, while at the same time reducing the axial force of the fastening members due to the formation of the gaps.

[0020] Here, "integrated" includes cases where the parts are integrally molded by die-casting using metals such as aluminum alloys and magnesium alloys, as well as cases where the parts are integrally molded using resins such as CFRP, and cases where the parts are integrated by bonding, etc.

[0021] A vehicle manufacturing method according to claim 2 is the vehicle manufacturing method according to claim 1, wherein the framework member is a rear module disposed at the rear of the vehicle, and the rear module further comprises a pair of left and right wheel arches disposed on the rear side of the pair of left and right side members and outboard in the vehicle width direction, and support members that support the pair of left and right wheel arches, and the pair of left and right side members, the pair of left and right wheel arches, and the support members are integrally molded by die casting.

[0022] In a vehicle manufacturing method according to claim 2, the frame member is a vehicle rear frame member disposed at the rear of the vehicle, and further includes a pair of left and right wheel arches and a support member. The pair of left and right wheel arches are provided on the vehicle rear side of the pair of left and right side members, respectively, and are disposed outward in the vehicle width direction, and the pair of left and right wheel arches are supported by the support members. The pair of left and right side members, the pair of left and right wheel arches, and the support members are integrally molded by die casting.

[0023] For this reason, compared to when only a pair of left and right side members are molded as a single unit, the parts become larger, making it more difficult to achieve the required dimensions. However, with the present invention, the dimensions can be adjusted by cooling, so it is possible to reduce the number of parts while still maintaining dimensional accuracy. This reduces the number of assembly steps, and ultimately reduces costs.

[0024] A vehicle manufacturing method according to claim 3 is the vehicle manufacturing method according to claim 2, wherein the battery pack includes a battery frame, and the battery frame includes a cross member that is disposed on the rear side of the vehicle, extends in the vehicle width direction, and is connected to the pair of left and right side members.

[0025] In a vehicle manufacturing method according to claim 3, the battery pack includes a battery frame. The battery frame includes a cross member disposed at the rear of the vehicle and extending in the vehicle width direction. The cross member is connected to a pair of left and right side members.

[0026] In other words, by providing the cross members on the front end portions of the pair of left and right side members on the battery frame, there is no need to provide cross members on the front end portions of the pair of left and right side members, which makes it possible to provide a flexible structure for the pair of left and right side members while maintaining the required strength for the rear module.

[0027] A vehicle manufacturing method according to a fourth aspect of the present invention is the vehicle manufacturing method according to the third aspect, wherein the die-cast is entirely cooled in the cooling step, and the battery frame is entirely heated in the heating step.

[0028] In the vehicle manufacturing method according to claim 4, the entire die-cast is cooled in the cooling process, and the entire battery frame is heated in the heating process. This suppresses heat transfer within the die-cast and battery frame, reduces temperature variations, and enables the desired temperature to be reached in a short time. [Effects of the Invention]

[0029] As described above, the vehicle manufacturing method according to the present invention can ensure the gap required for setting components and suppress a reduction in the axial force of fastening members due to the gap. [Brief explanation of the drawings]

[0030] [Figure 1] 1 is an exploded perspective view showing a vehicle to which a vehicle manufacturing method according to an embodiment of the present invention is applied; [Figure 2] FIG. 10 is a plan view showing the change in dimensions of the outer shape when the rear module is cooled. [Figure 3] FIG. 10 is a plan view showing the change in dimensions of the outer shape when the battery frame is heated. [Figure 4] 10A and 10B are enlarged cross-sectional views of the main part showing the assembly process of the rear module and the battery frame according to the present embodiment. [Figure 5] 10A and 10B are enlarged cross-sectional views of the main part showing the process of fastening the rear module and the battery frame according to the present embodiment. [Figure 6] FIG. 10 is an enlarged cross-sectional view of a comparative example showing a process of fastening a rear module and a battery frame; DETAILED DESCRIPTION OF THE INVENTION

[0031] Hereinafter, a vehicle manufacturing method according to one embodiment of the present invention will be described with reference to the drawings. Note that the arrows FR, UP, and RH shown as appropriate in each drawing indicate the front side, upper side, and right side in the left-right direction (width direction) of the vehicle, respectively. Furthermore, unless otherwise specified, when the front-rear, up-down, and left-right directions are used in the following description, they refer to front-rear in the front-rear direction of the vehicle, up-down in the up-down direction of the vehicle, and left-right in the left-right direction (width direction), respectively.

[0032] <Vehicle frame structure configuration> First, the configuration of a vehicle frame structure to which the vehicle manufacturing method according to this embodiment is applied will be described.

[0033] 1 shows an exploded perspective view of a vehicle 12 to which a vehicle frame structure 10 according to this embodiment is applied. In this embodiment, the vehicle 12 is divided into a front portion of the vehicle (hereinafter referred to as the "front module") 14, a central portion of the vehicle (hereinafter referred to as the "center module") 16, and a rear portion of the vehicle (hereinafter referred to as the "rear module") 18.

[0034] (front module) In this embodiment, for example, the front module 14 is configured to include a pair of left and right front side members (side members) 20 extending in the fore-and-aft direction of the vehicle, a pair of left and right wheel arches 22 each formed to include the front side members 20 and positioned on the outside in the vehicle width direction and capable of accommodating wheels (not shown), and a cross member 24 extending in the vehicle width direction and connecting the pair of left and right wheel arches 22.

[0035] The front side members 20, wheel arches 22, and cross members 24 are integrally molded (integrated) by die-casting using aluminum alloy, magnesium alloy, etc. In addition to metal, they may also be integrally molded using resin such as carbon fiber reinforced plastic (CFRP) or glass fiber reinforced plastic (GFRP).

[0036] (Center module) In this embodiment, for example, the center module 16 includes a battery pack 26. The battery pack 26 is made of a light metal such as an aluminum alloy and has a rectangular plate shape with its longitudinal direction aligned with the front-to-rear direction of the vehicle in a plan view. The battery pack 26 is supported by a battery frame 28.

[0037] The battery frame 28 has, for example, a rectangular frame shape with the longitudinal direction being the fore-and-aft direction of the vehicle when viewed in a plane, and is integrally constructed (integrated) with a pair of left and right side frames 30 extending in the fore-and-aft direction of the vehicle on both outer sides of the battery pack 26 in the vehicle width direction, a front cross member 32 connecting the front ends of the pair of left and right side frames 30, and a rear cross member 33 connecting the rear ends of the pair of left and right side frames 30.

[0038] The battery frame 28 is also provided with a pair of center cross members 34 that extend along the vehicle width direction and are arranged at the front and rear of the vehicle in the center of the vehicle in the longitudinal direction. Furthermore, a cross member 36 that extends in the vehicle width direction is provided at the rear end of the battery frame 28 in the longitudinal direction of the vehicle, and an accessory member 38 is mounted behind the cross member 36 at the rear end of the battery frame 28.

[0039] The battery frame 28 is formed by extrusion molding or the like using materials such as aluminum alloy, magnesium alloy, etc. Other than metal, it may also be formed from resin such as CFRP.

[0040] (rear module) In this embodiment, for example, the rear module 18 is configured to include a pair of left and right rear side members (side members) 40 extending in the fore-and-aft direction of the vehicle, a pair of left and right wheel arches 42 each formed to include the rear side members 40 and positioned on the outside in the vehicle width direction and capable of accommodating wheels (not shown), and a support member 44 extending in the vehicle width direction and connecting the pair of left and right wheel arches 42.

[0041] The rear side member 40, the wheel arch 22, and the support member 44 are integrally molded by die casting using an aluminum alloy, a magnesium alloy, or the like. Alternatively, they may be integrally molded using a resin such as CFRP.

[0042] <Vehicle manufacturing method> Here, a vehicle manufacturing method according to this embodiment will be described.

[0043] In this embodiment, the vehicle manufacturing method relates to the assembly of the center module 16 and rear module 18 shown in Fig. 1. This vehicle manufacturing method includes a cooling process, a heating process, an assembling process, and a fastening process.

[0044] First, in the cooling process, the rear module 18 is cooled. For example, the rear module 18 is cooled from about 20°C to about 0°C. One example of a cooling method is to submerge the rear module 18 in a dedicated pool tank. After being released from the mold, the rear module 18 is stored as inventory, and is therefore cooled by air during the storage period, and is maintained at about 20°C.

[0045] Meanwhile, in the heating step, the battery frame 28 is heated. For example, the battery frame 28 is heated to approximately 20°C to approximately 40°C. One example of a heating method is to place the battery frame 28 in a dedicated furnace. Alternatively, a heating method using a heater such as a gas burner can also be applied. The cooling step and heating step can be performed in any order.

[0046] Then, in the assembly process, while the pair of left and right rear side members 40 of the rear module 18 and the pair of left and right side frames 30 of the battery frame 28 are maintained at different temperatures, the pair of left and right side frames 30 are assembled (set) to the pair of left and right rear side members 40 from the outside in the vehicle width direction, as shown in Figure 4(A).

[0047] Next, in the fastening process, while the pair of left and right rear side members 40 of the rear module 18 and the pair of left and right side frames 30 of the battery frame 28 are maintained at approximately the same temperature, the pair of left and right side frames 30 and the pair of left and right rear side members 40 are fastened together using fastening bolts (fastening members) 46, as shown in Fig. 5(B). In this manner, the vehicle 12 is manufactured in this embodiment.

[0048] <Actions and effects of the vehicle manufacturing method> Next, the operation and effects of the vehicle manufacturing method according to this embodiment will be described.

[0049] As described above, the vehicle manufacturing method according to this embodiment includes the cooling step, the heating step, the assembling step, and the fastening step.

[0050] In the cooling process, the rear module 18 is cooled from approximately 20°C to approximately 0°C. Here, FIG. 2 shows the outer shape of the rear module 18 in a plan view, with the two-dot chain line indicating the state before the cooling process and the solid line indicating the state after the cooling process. In FIG. 2, the denser the dots, the greater the shrinkage rate, and the shrinkage rate is greater on the outer side than on the inner side in the vehicle width direction. In this embodiment, as shown in FIG. 2, the cooling process causes the outer shape of the rear module 18 to shrink, and the separation distance in the vehicle width direction between the pair of left and right rear side members 40 becomes smaller.

[0051] Furthermore, during the heating process, the battery frame 28 is heated to approximately 20°C to approximately 40°C. Here, FIG. 3 shows the outer shape of the battery frame 28 in a plan view, with the two-dot chain line indicating the state before the heating process and the solid line indicating the state after the heating process. In FIG. 3, the denser the dots, the greater the expansion rate, and the expansion rate is greater on the outer side than on the inner side in the vehicle width direction. In this embodiment, as shown in FIG. 3, the heating process causes the outer shape of the battery frame 28 to expand, increasing the separation distance in the vehicle width direction between the pair of left and right side frames 30.

[0052] The cooling process described above causes the pair of left and right rear side members 40 of the rear module 18 to contract, reducing the separation distance in the vehicle width direction. Meanwhile, the heating process causes the pair of left and right rear side members 40 of the battery frame 28 to expand, increasing the separation distance in the vehicle width direction.

[0053] For this reason, in this embodiment, as shown in Fig. 4(A), a gap t can be provided between the pair of left and right rear side members 40 of the rear module 18 and the pair of left and right side frames 30 of the battery frame 28. This makes it possible to assemble (set) the pair of left and right side frames 30 of the battery frame 28 to the outer sides of the pair of left and right rear side members 40 of the rear module 18 in the vehicle width direction, as shown in Fig. 4(B).

[0054] Next, in the fastening process, the pair of left and right rear side members 40 of the rear module 18 and the pair of left and right side frames 30 of the battery frame 28 are fastened to each other while maintaining the pair of left and right side frames 30 at approximately the same temperature.

[0055] By bringing the pair of left and right rear side members 40 and the pair of left and right side frames 30 to approximately the same temperature, the pair of left and right rear side members 40 of the rear module 18 that contracted during the cooling process and the pair of left and right rear side members 40 of the battery frame 28 that expanded during the heating process return to their original dimensional states.

[0056] That is, the pair of left and right rear side members 40 of the rear module 18 expand as their temperature rises, and the pair of left and right rear side members 40 of the battery frame 28 contract as their temperature drops. As a result, as shown in Fig. 5(A), the gap t (see Fig. 4(A)) between the pair of left and right rear side members 40 of the rear module 18 and the pair of left and right side frames 30 of the battery frame 28 becomes smaller. In this state, the two are fastened together with fastening bolts 46 as shown in Fig. 5(B), and the vehicle 12 (see Fig. 1) is manufactured.

[0057] As a comparative example, as shown in FIG. 6, when a pair of left and right rear side members 102 of the rear module 100 and a pair of left and right side frames 106 of the battery frame 104 are fastened together with a gap t' between them, the axial force of the fastening bolts 108 decreases, and the fastening force decreases.

[0058] In contrast, in this embodiment, as shown in Fig. 5(B), the pair of left and right rear side members 40 of the rear module 18 and the pair of left and right side frames 30 of the battery frame 28 are fastened together by the fastening bolts 46 with almost no gap t (see Fig. 4(A)) between them. As a result, in this embodiment, it is possible to suppress a decrease in the axial force of the fastening bolts 46 due to the formation of the gap t.

[0059] In other words, in this embodiment, it is possible to achieve the contradictory objectives of securing the gap t required to set the rear module 18 inside the vehicle width direction of the battery frame 28, while at the same time reducing the axial force of the fastening bolt 46 by forming this gap t.

[0060] On the other hand, in this embodiment, in the rear module 18, the pair of left and right rear side members 40, the pair of left and right wheel arches 22, and the support member 44 are integrally formed by die casting.

[0061] For this reason, compared to when, for example, only the pair of left and right rear side members 40 are integrally molded, the parts become larger, making it more difficult to achieve the required dimensions. However, in this embodiment, the dimensions can be adjusted by cooling, so it is possible to reduce the number of parts while ensuring dimensional accuracy. This reduces the number of assembly steps, and as a result, reduces costs.

[0062] In this embodiment, the battery pack 26 is equipped with a battery frame 28, which includes a cross member 36 disposed on the rear side of the vehicle and extending in the vehicle width direction. The cross member 36 is connected to a pair of left and right rear side members 40 of the rear module 18.

[0063] That is, by providing the cross members 36 provided on the front end sides of the pair of left and right rear side members 40 on the battery frame 28 side, it is no longer necessary to provide the cross members 36 on the front end sides of the pair of left and right rear side members 40. This makes it possible to provide a structure in which the pair of left and right rear side members 40 are easily flexible while maintaining the required strength in the rear module 18. Although not shown, cross members may be provided on the front end sides of the pair of left and right rear side members 40.

[0064] Furthermore, in this embodiment, the entire die-cast rear module 18 is cooled in the cooling process, and the entire battery frame 28 is heated in the heating process. This suppresses heat transfer within the rear module 18 and battery frame 28, reduces temperature variations, and enables the desired temperature to be reached in a short time.

[0065] However, since the cooling process only requires that at least one pair of left and right rear side members 40 be cooled, it is not necessary to cool the entire rear module 18. Furthermore, since the heating process only requires that at least one pair of left and right side frames 30 be heated, it is not necessary to heat the entire battery frame 28.

[0066] <Supplementary explanation of the above embodiment> In the above embodiment, an example has been described in which the frame member is applied to the rear side member 40 on the rear module 18 side, but the present invention is not limited to this. For example, the frame member may be applied to the front side member 20 on the front module 14 side shown in Fig. 1. Furthermore, the frame member may be applied to the rear side member 40 on the rear module 18 side and the front side member 20 on the front module 14 side.

[0067] In addition, in this embodiment, the rear module 18 is cooled from approximately 20°C to approximately 0°C, and the battery frame 28 is heated from approximately 20°C to approximately 40°C, but the temperatures can be changed as appropriate depending on the shapes of the rear module 18 and the battery frame 28, etc.

[0068] In this embodiment, the assembly of a pair of left and right side members of a framework member and a pair of left and right side frames of a battery frame has been described, but the present invention is not limited to this. For example, the present invention can also be applied to a method of assembling an outer member that is attached to the outside in the longitudinal direction of the vehicle and an inner member that is attached to the inside in the longitudinal direction of the vehicle of the outer member.

[0069] Although one embodiment of the present invention has been described above, the present invention is not limited to such an embodiment, and one embodiment may be appropriately combined with various modified examples, and the present invention may of course be embodied in various forms as long as it does not deviate from the gist of the present invention.

[0070] <Additional Notes> The vehicle manufacturing method according to the present invention may be implemented by appropriately combining the following configurations.

[0071] (Configuration 1) A vehicle manufacturing method for a vehicle skeleton structure including: a battery frame disposed under a vehicle, supporting a battery pack, and including a pair of left and right side frames located on both outer sides in the vehicle width direction, the pair of left and right side frames being integrally molded; and a skeleton member disposed at least at one of the front and rear of the vehicle, and including a pair of left and right side members extending in the fore-and-aft direction of the vehicle, the pair of left and right side members being integrally molded, the method including: a cooling process for cooling at least the pair of left and right side members; a heating process for heating at least the pair of left and right side frames; an assembly process for assembling the pair of left and right side members to the inside of the pair of left and right frames in the vehicle width direction while the pair of left and right side members and the pair of left and right side frames are maintained at different temperatures; and a fastening process for fastening the pair of left and right side frames to the pair of left and right side members while the pair of left and right side members and the pair of left and right side frames are maintained at approximately the same temperature.

[0072] (Configuration 2) The skeletal member is a rear module arranged at the rear of the vehicle, and the rear module further includes a pair of left and right wheel arches that are respectively provided on the rear side of the pair of left and right side members and positioned outside in the vehicle width direction, and support members that support the pair of left and right wheel arches, and the pair of left and right side members, the pair of left and right wheel arches, and the support members are molded integrally by die-casting.

[0073] (Configuration 3) The battery pack includes a battery frame, which is disposed on the rear side of the vehicle and includes a cross member that extends in the vehicle width direction and is connected to the pair of left and right side members.

[0074] (Configuration 4) The entire die-cast is cooled in the cooling step, and the entire battery frame is heated in the heating step. [Explanation of symbols]

[0075] 10 Vehicle frame structure 12 vehicles 14 Front module (front of vehicle) 16 Center Module 18 Rear module (rear of vehicle) 20 Front side member (side member) 22 Wheel arch 24 Cross member 26 Battery pack 28 Battery Frame 30 Side frame 36 Cross member 40 Rear side member 42 Wheel arch 44 Support member 46 Fastening bolt (fastening member) t gap

Claims

1. a battery frame that is disposed under the vehicle, supports the battery pack, and includes a pair of left and right side frames that are disposed on both outer sides in the vehicle width direction, the pair of left and right side frames being integrated together; a frame member including a pair of left and right side members disposed at least in one of a front portion and a rear portion of the vehicle and extending in a longitudinal direction of the vehicle, the pair of left and right side members being integrated; A vehicle manufacturing method for a vehicle frame structure comprising: a cooling step of cooling at least the pair of left and right side members; a heating step of heating at least the pair of left and right side frames; an assembling process of assembling the pair of left and right side members to the inner sides of the pair of left and right frames in a vehicle width direction while the pair of left and right side members and the pair of left and right side frames are maintained at different temperatures; a fastening process of fastening the pair of left and right side frames to the pair of left and right side members while the pair of left and right side members and the pair of left and right side frames are maintained at substantially the same temperature; A vehicle manufacturing method comprising:

2. the framework member is a rear module disposed at a rear portion of the vehicle, The rear module is a pair of left and right wheel arches that are provided on vehicle rear sides of the pair of left and right side members and arranged outward in a vehicle width direction; support members for supporting the pair of left and right wheel arches; Furthermore, 2. The vehicle manufacturing method according to claim 1, wherein the pair of left and right side members, the pair of left and right wheel arches, and the support member are integrally formed by die casting.

3. the battery pack comprises a battery frame; 3. The vehicle manufacturing method according to claim 2, wherein the battery frame includes a cross member that is disposed on the rear side of the vehicle, extends in the vehicle width direction, and is connected to the pair of left and right side members.

4. The vehicle manufacturing method according to claim 3 , wherein the die-cast is entirely cooled in the cooling step, and the battery frame is entirely heated in the heating step.

Images