Vehicle

Abstract

To suppress a torsional load transmitted to a battery pack mounted on a floor of a vehicle.SOLUTION: The battery pack 20 (battery case 22) is mounted below a floor panel 60 of the vehicle. The battery case 22 is fixed to the floor panel 60 by a plurality of first fixing portions (25a, 25b, and 27a to 27e) disposed along a first imaginary line L1 extending in the vehicle front-rear direction at the center of a tread Tr of the automobile, and a plurality of second fixing portions (25c, 25d, 27a,, and) disposed along a second imaginary line L2 extending in the vehicle left-right direction at the center of a wheel base Wb of the automobile. 27f 27g.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to vehicles. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2021-123227 (Patent Document 1) discloses a mounting structure for a battery pack installed on the floor of a vehicle. Patent Document 1 discloses an example in which the edge of the upper case of the battery pack is fixed to the floor panel by a fixing structure (such as a fastening bolt). In this mounting structure, a first edge portion close to the suspension mounting portion is not fixed to the floor panel, and a second edge portion farther from the suspension mounting portion is fixed to the floor panel. With this mounting structure, it is said that the torsional load transmitted from the floor panel to the battery pack case is effectively released at the first edges corresponding to the four corners of the battery pack case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-123227 Summary of the Invention [Problem to be solved by the invention]

[0004] In the battery pack mounting structure disclosed in Patent Document 1, there is a concern that when a large torsional load is input to the floor panel, the torsional load transmitted to the battery pack case cannot be effectively released.

[0005] An object of the present disclosure is to suitably suppress torsional loads transmitted to a battery pack mounted on the floor of a vehicle. [Means for solving the problem]

[0006] The vehicle of the present disclosure is a vehicle with a battery pack mounted on the floor, the battery pack including a battery case that houses battery cells. The battery case is fixed to the floor by a plurality of first fixing parts arranged along a first imaginary line that extends in the fore-and-aft direction of the vehicle at the center of the vehicle tread, and a plurality of second fixing parts arranged along a second imaginary line that extends in the left-and-right direction of the vehicle at the center of the vehicle wheelbase.

[0007] When a large torsional load is applied to the floor, the displacement around a first imaginary line extending in the longitudinal direction of the vehicle at the center of the vehicle tread and a second imaginary line extending in the lateral direction of the vehicle at the center of the vehicle wheelbase is small. With this configuration, the battery case is fixed to the floor by a first fixing part arranged along the first imaginary line and a second fixing part arranged along the second imaginary line, thereby suppressing the torsional load transmitted to the battery pack.

[0008] Preferably, the battery pack includes a pair of longitudinal sides extending parallel to the longitudinal direction of the vehicle and a pair of lateral sides extending parallel to the lateral direction of the vehicle. The first imaginary line may pass through the center of the battery case and extend in the longitudinal direction of the vehicle, and the second imaginary line may pass through the center of the battery case and extend in the lateral direction of the vehicle.

[0009] According to this configuration, the center of the battery pack in the front-rear and left-right directions is fixed to the floor, so the battery pack can be fixed to the floor firmly and in a balanced manner.

[0010] Preferably, the first fixing portion may be arranged on an edge of the battery case and in a center portion of the battery case, and the second fixing portion may be arranged on an edge of the battery case and in a center portion of the battery case.

[0011] This configuration makes it possible to effectively suppress vibration of the battery pack.

[0012] Preferably, the first fixing portion and the second fixing portion may be formed of a fastening member.

[0013] This configuration allows the ionization hack to be detachable from the vehicle. [Effects of the Invention]

[0014] According to the present disclosure, it is possible to suitably suppress the torsional load transmitted to a battery pack mounted on the floor of a vehicle. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram showing a schematic overall configuration of a vehicle equipped with a battery pack according to an embodiment of the present invention; [Figure 2] 1 is a schematic perspective view of a battery pack according to an embodiment of the present invention; [Figure 3] This is a top view of the floor of the vehicle body. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. [Figure 5] 3A and 3B are diagrams illustrating the fastening points of the battery pack according to the present embodiment. [Figure 6] 10A and 10B are diagrams illustrating the torsional deformation mode of a floor panel. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals, and their description will not be repeated. The dimensional relationships (length, width, thickness, etc.) in each drawing do not reflect the actual dimensional relationships.

[0017] FIG. 1 is a diagram showing a schematic overall configuration of a vehicle 1 equipped with a battery pack 20 according to this embodiment. The vehicle 1 is equipped with a battery pack 20 that stores electric power for traveling. The vehicle 1 is configured to be able to travel using the electric power stored in the battery pack 20. In this embodiment, the vehicle 1 is an electric vehicle (BEV) that does not have an engine (internal combustion engine), but it may also be a hybrid vehicle (HEV) or a plug-in hybrid vehicle (PHEV) that has an engine. In each diagram of this embodiment, Fr indicates the front of the vehicle, Rr indicates the rear of the vehicle, R indicates the right side of the vehicle, L indicates the left side of the vehicle, U indicates the upside, and D indicates the downside.

[0018] The vehicle 1 includes a control device (ECU: Electronic Control Unit) 2. The ECU 2 is configured to control charging and discharging of the battery pack 20. The ECU 2 includes a processor, a RAM (Random Access Memory), and a storage device (none of which are shown). The ECU 2 may be a computer. The processor may be a CPU (Central Processing Unit).

[0019] The vehicle 1 further includes a traveling drive unit 3 and drive wheels W. The traveling drive unit 3 includes a PCU (Power Control Unit) and an MG (Motor Generator), not shown, and is configured to run the vehicle 1 using power stored in the battery pack 20. The PCU includes, for example, an inverter, a converter, and a relay (hereinafter referred to as an SMR (System Main Relay)). The PCU is controlled by the ECU 2. The MG is, for example, a three-phase AC motor generator. The MG is configured to be driven by the PCU and rotate the drive wheels W. The PCU drives the MG using power supplied from the battery pack 20. The MG is also configured to perform regenerative power generation and supply the generated power to the battery pack 20. The SMR is configured to switch between connection and disconnection of a power path from the battery pack 20 to the PCU. The SMR is closed (connected) when the vehicle 1 is running.

[0020] The battery pack 20 is mounted on the floor of the body 10 of the vehicle 1, and is mounted outside the passenger compartment (under the floor) of the vehicle 1. FIG. 2 is a schematic perspective view of the battery pack 20 according to this embodiment. The battery pack 20 includes a battery case 22. The battery case 22 is composed of a lower case 221 and an upper case 222. The battery case 22 is formed by fixing the flange of the upper case 222 to the flange of the lower case 221 via a sealing member. The battery case 22 accommodates a battery module M (see FIG. 4), a battery monitoring module (not shown), and the like.

[0021] The battery case 22 has a substantially rectangular shape and includes a pair of longitudinal sides 20c, 20d extending substantially parallel to the vehicle longitudinal direction and a pair of lateral sides 20a, 20b extending substantially parallel to the vehicle lateral direction. The longitudinal sides 20c, 20d and the lateral sides 20a, 20b form the periphery of the battery case 22 (lower case 221, upper case 222). A first imaginary line L1, indicated by a dashed-dotted line, extends in the vehicle longitudinal direction. A second imaginary line L2, indicated by a dashed-dotted line, extends in the vehicle lateral direction. The first imaginary line L1 is located at the center between the longitudinal sides 20c and 20d. The second imaginary line L2 is located at the center between the lateral sides 20a and 20b. In the present disclosure, the point where the first imaginary line L1 and the second imaginary line L2 intersect is also referred to as the center of the battery case 22. The first imaginary line L1 passes through the center of the battery case 22 and extends in the front-to-rear direction of the vehicle. The second imaginary line L2 passes through the center of the battery case 22 and extends in the left-to-right direction of the vehicle.

[0022] The upper case 222 is provided with four mounting brackets 25 (25a, 25b, 25c, 25d). The mounting brackets 25 are fixed to the upper case 222 by, for example, welding. The mounting bracket 25a is fixed at a position where the left-right side 20a intersects with the first imaginary line L1. The mounting bracket 25b is fixed at a position where the left-right side 20b intersects with the first imaginary line L1. The mounting bracket 25c is fixed at a position where the front-rear side 20c intersects with the second imaginary line L2. The mounting bracket 25d is fixed at a position where the front-rear side 20d intersects with the second imaginary line L2. The mounting brackets 25 are formed with bolt insertion holes 251. Two bolt insertion holes 251 are formed in the mounting bracket 25, and are located on both sides of the first imaginary line L1 or the second imaginary line L2.

[0023] A plurality of mounting bolts 27 are provided on the upper case 222. The mounting bolts 27 have their bases fixed to the upper case 222 by, for example, welding, and have male thread portions 271 protruding from the base. In this embodiment, seven mounting bolts 27 (27a to 27g) are fixed to the upper case 222. Mounting bolt 27a is fixed to the center of the battery case 22 (upper case 222), and mounting bolts 27b, 27c, 27d, and 27e are fixed to both sides of the mounting bolt 27 in the direction of the first imaginary line L1. Mounting brackets 25a and 25b and mounting bolts 27a, 27b, 27c, 27d, and 27e are arranged along the first imaginary line L1 (on the first imaginary line L1). Mounting bolts 27f and 27g are fixed to both sides of the mounting bolt 27 in the direction of the second imaginary line L2. The mounting brackets 25c and 25d and the mounting bolts 27a, 27f, and 27g are arranged along (on) the second imaginary line L2.

[0024] FIG. 3 is a top view of the floor of the vehicle body 10. In this embodiment, the vehicle body 10 has a monocoque structure. The floor of the vehicle body 10 includes a pair of front side members 30 arranged in the longitudinal direction of the vehicle, a pair of side members (side sills) 40, a pair of rear floor side members 45, a plurality of cross members 50 connecting the left and right side members 40, and a floor panel 60. The battery pack 20 is mounted on the underside (under the floor) of the floor panel 60. The battery pack 20 is arranged outside the passenger compartment of the vehicle 1.

[0025] The vehicle 1 has a right front wheel FRw, a left front wheel FLw, a right rear wheel RRw, and a left rear wheel RLw. The vehicle 1 is front-wheel drive, and the right front wheel FRw and the left front wheel FLw correspond to the drive wheels W. The suspension struts (damper and coil spring assemblies (not shown)) of each wheel are fixed to suspension towers 65. The suspension towers 65 are fixed directly or indirectly to the front side members 30 and the rear floor side members 45. The road input (load) from the wheels is input through the suspension towers 65 and is input to the floor panel 60 from approximately the four corners of the floor panel 60. Note that the suspension towers 65 are shown schematically.

[0026] The battery pack 20 is mounted so that the first imaginary line L1 is located at the center of the tread Tr of the vehicle 1, and the second imaginary line L2 is located at the center of the wheelbase Wb. In this embodiment, the tread Tr is the tread of the front wheels (right front wheel FRw, left front wheel FLw). The first imaginary line L1 also corresponds to the "first imaginary line extending in the longitudinal direction of the vehicle at the center of the tread" in this disclosure. The second imaginary line L2 also corresponds to the "second imaginary line extending in the transverse direction of the vehicle at the center of the wheelbase" in this disclosure. A reinforcing plate 55 is fixed to the floor panel 60 at a location facing the mounting bolt 27 arranged along the first imaginary line L1. The floor panel 60 and the reinforcing plate 55 are formed with insertion holes 61 through which the male thread portions 271 of the mounting bolts 27 (27a to 27g) are inserted.

[0027] 4 is a cross-sectional view taken along line IV-IV in FIG. 3. A battery module M is housed inside the battery case 22. The battery module M is an assembled battery made up of battery cells, such as lithium-ion batteries or nickel-metal hydride batteries. The battery pack 20 (battery case 22) is fixed to the underside of a floor panel 60. A weld nut 101 is fixed inside the cross member 50 at the front of the vehicle. A bolt 100 is inserted into a bolt insertion hole 251 (see FIG. 2) of the mounting bracket 25a, and the bolt 100 is screwed into the weld nut 101, thereby fixing (fastening) the mounting bracket 25a to the floor panel 60. A weld nut 101 is fixed inside the cross member 50 at the rear of the vehicle. A bolt 100 is inserted into a bolt insertion hole 251 of the mounting bracket 25b, and the bolt 100 is screwed into the weld nut 101, thereby fastening the mounting bracket 25b to the floor panel 60.

[0028] The male thread portion 271 of the mounting bolt 27 is inserted into the insertion hole 61 of the floor panel 60 and the reinforcing plate 55, and a nut 200 is threaded onto the male thread portion 271, thereby fastening the mounting bolt 27 to the floor panel 60. An opening 51 is formed in the cross member 50, which is disposed in the center of the vehicle in the longitudinal direction. The nut 200 is threaded onto the male thread portion 271 using this opening 51.

[0029] Mounting brackets 25c and 25d and mounting bolts 27c, 27e, 27f, and 27g, which are not shown in Figure 4 (a cross-sectional view taken along line IV-IV in Figure 3), are similarly fixed (fastened) to floor panel 60. Fastening mounting brackets 25a to 25d and mounting bolts 27a to 27g to floor panel 60 fixes battery case 22 (battery pack 20) ​​to the floor of vehicle 1.

[0030] FIG. 5 is a diagram schematically illustrating fastening locations of battery pack 20 in this embodiment. In FIG. 5, black circles indicate fastening locations of battery pack 20 (battery case 22) to floor panel 60, and correspond to mounting brackets 25a-25d and mounting bolts 27a-27g. Mounting brackets 25a and 25b and mounting bolts 27a-27e are arranged along a first imaginary line L1 and correspond to an example of a "first fixing portion" in the present disclosure. Mounting brackets 25c and 25d and mounting bolts 27a, 27f, and 27g are arranged along a second imaginary line L2 and correspond to a "second fixing portion" in the present disclosure. First imaginary line L1 is located at the center of tread Tr of vehicle 1, and second imaginary line L2 is located at the center of wheelbase Wb.

[0031] 5, the white circles indicate the locations (corresponding to suspension towers 65) where road surface input (load) from the wheels is input, and the road surface input (load) is input from approximately the four corners of floor panel 60. This road surface input (load) causes floor panel 60 to deform.

[0032] FIG. 6 is a diagram illustrating a torsional deformation mode of the floor panel 60. When a torsional load is applied to the floor panel 60 due to road surface input (load) input from the four corners of the floor panel 60, torsional deformation occurs with the first imaginary line L1 and the second imaginary line L2 as nodes, as shown by the dashed lines. The displacement (deformation) is small at the torsional nodes. As shown in FIG. 5, the fastening points of the battery pack 20 are arranged along the first imaginary line L1 and the second imaginary line L2 (arranged on the first imaginary line L1 and the second imaginary line L2). Therefore, it is possible to suppress the torsional load transmitted from the first fixing portion (mounting brackets 25a, 25b, mounting bolts 27a-27e) and the second fixing portion (mounting brackets 25c, 25d, mounting bolts 27a, 27f, 27g) to the battery pack 20 (battery case 22).

[0033] In this embodiment, battery case 22 has a substantially rectangular shape, with first imaginary line L1 located at the center between front-rear sides 20c and 20d, and second imaginary line L2 located at the center between left-right sides 20a and 20b. Therefore, first fixing portions (mounting brackets 25a, 25b, mounting bolts 27a-27e) and second fixing portions (mounting brackets 25c, 25d, mounting bolts 27a, 27f, 27g) fix battery pack 20 to floor panel 60 along the center line of battery pack 20 in the front-rear direction and the left-right direction. This allows battery pack 20 to be fixed to floor panel 60 firmly and in a balanced manner.

[0034] In this embodiment, mounting brackets 25a and 25b of the first fixing portion are located on the periphery of battery pack 20, and mounting bolts 27a to 27e are located in the center of battery pack 20. Mounting brackets 25c and 25d of the second fixing portion are located on the periphery of battery pack 20, and mounting bolts 27a, 27f, and 27g are located in the center of battery pack 20. Since the periphery and center of battery pack 20 are fixed to floor panel 60, vibration of battery pack 20 can be suitably suppressed.

[0035] In this embodiment, mounting bracket 25 is fastened to floor panel 60 by bolt 100. Furthermore, mounting bolt 27 is fastened to floor panel 60 by nut 200. Therefore, battery pack 20 can be detached from vehicle 1.

[0036] In the above embodiment, the vehicle 1 having the battery pack 20 mounted thereon has a monocoque structure. However, the vehicle body may have a frame structure using a ladder frame or the like.

[0037] In the above embodiment, the battery pack 20 (battery case 22) is fastened to the floor panel 60 using the mounting bolt 27 having the male thread portion 271 protruding from a base fixed to the upper case 222. Instead of the mounting bolt 27, a stud bolt having a head disposed inside the upper case 222 may be used.

[0038] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0039] 1 vehicle, 2 control unit (ECU), 3 driving drive unit, 10 vehicle body, 20 battery pack, 22 battery case, 221 lower case, 222 upper case, 25 mounting bracket, 27 mounting bolt, 30 front side member, 40 side member, 45 rear floor side member, 50 cross member, 55 reinforcing plate, 60 floor panel, 65 suspension tower, 100 bolt, 101 weld nut, 200 nut, M battery module.

Claims

1. A vehicle with a battery pack mounted on the floor, The battery pack includes a battery case that houses battery cells, The battery case is A vehicle that is fixed to the floor by a plurality of first fixing portions arranged along a first imaginary line extending in the fore-and-aft direction of the vehicle at the center of the tread of the vehicle, and a plurality of second fixing portions arranged along a second imaginary line extending in the left-and-right direction of the vehicle at the center of the wheelbase of the vehicle.

2. The battery pack a pair of front-rear direction sides extending parallel to the front-rear direction of the vehicle; a pair of left and right sides extending parallel to each other in the left and right direction of the vehicle; the first imaginary line passes through the center of the battery case and extends in the front-rear direction of the vehicle; The vehicle according to claim 1 , wherein the second imaginary line passes through a center of the battery case and extends in a left-right direction of the vehicle.

3. 3. The vehicle according to claim 1, wherein the first fixing portion is disposed on a periphery of the battery case and a center portion of the battery case, and the second fixing portion is disposed on a periphery of the battery case and a center portion of the battery case.

4. The vehicle according to claim 3 , wherein the first fixing portion and the second fixing portion are formed of fastening members.

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