Configuration Structure of Power Unit and Rear Seat in Electric Vehicle

Abstract

Below the floor (2) of the vehicle body, the rear suspension cross member (4) is suspended and supported from the left and right side beams (3l, 3r). A drive unit (8) including a traveling motor (9) is installed on the rear suspension cross member (4), and a power supply unit (20) including a junction box (21) is installed above the floor (2). A frame member (43) is erected between brackets (42l, 42r) vertically provided on the left and right side beams (3l, 3r) to support the seat (39a) of the rear seat (39). The frame member (43) is disposed at a rear position relative to the power supply unit (20) and at a front position with a distance dimension (L1) from the rear end of the rear suspension cross member (4), so as to be used for mitigating the input from another vehicle in a rear collision.

Description

Technical Field

[0001] The present invention relates to an arrangement structure of a power supply unit and a rear seat in an electric vehicle. Background Art

[0002] An electric vehicle is equipped with various power supply units that control the input and output of power to a driving battery. For example, as power supply units, a junction box that connects a driving battery and power loads such as a driving motor, a charger that charges the driving battery with power from an external power supply such as a charging station, a DC-AC inverter that converts DC power from the driving battery into AC power for use in household electricity, or an inverter for power supply control and regeneration control of the driving motor can be cited. These power supply units are connected to power loads such as a driving battery and a driving motor via power lines.

[0003] Since the breakage of a power supply unit or the disconnection of a power line can cause a short circuit during a vehicle collision, the installation position of the power supply unit and the routing path of the power line are carefully studied and set.

[0004] For example, Patent Document 1 discloses a rear-wheel drive electric vehicle that employs countermeasures against rear collisions. In this electric vehicle, the left and right rear wheels are supported by a rear suspension cross member that is suspended and supported under the floor of the vehicle body, and a driving motor equipped with an inverter and a drive axle are mounted on the suspension cross member as a drive unit to drive the rear wheels. Under the floor, a junction box, a charger, and a DC-AC inverter are arranged as power supply units above the drive unit. Each power supply unit, the inverter of the driving motor, and the driving battery are connected via power lines. Moreover, the power supply unit and the drive unit are arranged inside the contour line when viewed from above the rear suspension cross member. The strong rear suspension cross member is not easily deformed during a rear collision, thereby preventing damage to the power supply unit and the drive unit.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-151174

[0008] Technical Problem to be Solved by the Invention

[0009] The technology of Patent Document 1 is premised on a vehicle body structure in which a drive unit and a power supply unit are both disposed on a rear suspension cross member on the lower side of the floor. However, a vehicle body structure in which the power supply unit is relocated to the upper side of the floor is also widely implemented. In such a vehicle body structure, since it is also necessary to connect a junction box and an inverter of a drive motor through a power line, etc., the power supply unit is disposed near directly above the drive unit, that is, in a position affected by a rear collision. And, since the power supply unit that is remotely located upward from the rear suspension cross member via the floor is hardly protected by the rear suspension cross member, effective protection measures have been needed all along. Summary of the Invention

[0010] The present invention has been completed to solve the above-described technical problems, and an object thereof is to provide a configuration structure of a power supply unit and a rear seat in an electric vehicle that can more reliably protect the power supply unit and prevent breakage during a rear collision in a rear-wheel drive vehicle body structure in which the power supply unit is disposed on the upper side of the vehicle body floor and further, a rear seat is disposed directly above the power supply unit.

[0011] Technical Means for Solving the Technical Problem

[0012] To achieve the above object, a configuration structure of a power supply unit and a rear seat in an electric vehicle according to the present invention, the electric vehicle including: a rear suspension cross member that is suspended and supported by a pair of left and right side members extending in the front-rear direction on the lower side of the vehicle body floor, and supports the left and right rear wheels via a suspension; a drive unit that is mounted on the rear suspension cross member on the lower side of the floor and includes at least a drive motor that drives the left and right rear wheels; a power supply unit that is mounted on the upper side of the floor and includes at least a junction box that relays power from a drive battery and supplies the power to the drive motor; and a rear seat that is disposed directly above the power supply unit, a rear portion of a seat cushion of the rear seat is supported by a frame member that is spanned in the left-right direction between brackets provided on the pair of left and right side members on the upper side of the floor, and the frame member is disposed at a rear side position relative to the power supply unit and at a front side position relative to a rear end of the rear suspension cross member (protection range 1).

[0013] According to the configuration structure of the power supply unit and the rear seat in the electric vehicle configured as described above, the frame member is configured as a rigid structure to support the weight of the rear seat and the weight of an occupant. And, the rear seat is disposed directly above the power supply unit, and the rear portion of the seat cushion of the rear seat is supported by the frame member. Moreover, the frame member is located at the rear side relative to the power supply unit and at the front side relative to the rear end of the rear suspension cross member.

[0014] Therefore, during a subsequent collision, for another vehicle that deforms the rear part of the floor and intrudes forward, the intrusion of the other vehicle is first blocked by the rear end of the rear suspension cross member. In a case where the intrusion of the other vehicle cannot be blocked only by the rear end of the rear suspension cross member, in addition to the rear suspension cross member, the frame member is used to block the entry of the other vehicle. As a result, since the input from the other vehicle is mitigated in two stages, it is possible to prevent the other vehicle from colliding with the power unit, and thus it is possible to prevent damage to the power unit caused by the collision.

[0015] As another mode, preferably, the frame member is disposed at an upper position with respect to the power unit (protection range 2).

[0016] According to the configuration of the power unit and the rear seat in the electric vehicle configured as described above, since the rear end of the rear suspension cross member is disposed below the power unit and the frame member is disposed above the power unit, before a collision with the power unit, it is possible to reliably collide the other vehicle with the rear end of the rear suspension cross member and the frame member regardless of the intrusion height to mitigate the input. Moreover, by disposing the frame member above the power unit, even if the frame member deforms or moves toward the power unit side due to the intrusion of the other vehicle, it is possible to prevent the frame member from interfering with the power unit, and thus it is possible to more reliably protect the power unit and prevent damage.

[0017] As another mode, preferably, the floor is formed with a storage recess at a position behind the rear seat, the seat cushion of the rear seat is supported so as to be rotatable about the frame member as an axis, the seat back of the rear seat is supported so as to be rotatable relative to the seat cushion, and in a state where the seat back is rotated to coincide with the seat cushion, by turning the entire rear seat about the frame member as an axis rearward, the seat cushion can be housed in the storage recess, and the frame member is disposed at an upper position with respect to the power unit (protection range 3).

[0018] According to the configuration of the power unit and the rear seat in the electric vehicle configured as described above, in a state where the rear seat is housed in the storage recess, another vehicle that deforms the rear part of the floor and intrudes forward by a rear collision first collides with the rear seat in the storage recess. Depending on the collision conditions such as the intrusion height of the other vehicle, the behavior of the rear seat is different. For example, it may crush in the front-rear direction while maintaining its posture, or bounce up while rotating about the frame member as an axis, or both behaviors may occur simultaneously.

[0019] In the case where the rear seat is crushed in the front-rear direction, since the rear seat is crushed while the forward movement thereof is restricted by the rigid frame member, the input from another vehicle is absorbed by the polyurethane material or the like inside, so that the input at the time when another vehicle collides with the rear end of the rear suspension cross member or the input at the time when it collides with the frame member is alleviated subsequently. Further, in the case where the rear seat bounces, since the frame member serving as the rotation center is disposed at an upper position compared to the power unit, all parts of the rear seat after bouncing are located above the power unit, thereby reliably preventing the rear seat from colliding with the power unit.

[0020] As another aspect, it is preferable that there are further provided: a front floor cross member and a rear floor cross member which are respectively formed to extend in the left-right direction on the upper surface of the floor, and the left and right ends of the front floor cross member and the rear floor cross member are respectively connected to the pair of left and right side beams; and a unit cover whose front edge is fixed to the front floor cross member, whose rear edge is fixed to the rear floor cross member, and which covers the power unit from above, and the frame member is disposed at a rear side position compared to the unit cover (protection range 4).

[0021] According to the configuration structure of the power unit and the rear seat in the electric vehicle configured as described above, since the front edge and the rear edge of the unit cover are fixed to the front and rear floor cross members and the position displacement is restricted, the strength of the unit cover in the front-rear direction is increased. And since the input from another vehicle is alleviated by the collision with the rear end of the rear suspension cross member, alleviated by the collision with the frame member, and alleviated by the collision with the cover having high strength in the front-rear direction, the collision of another vehicle with the power unit is further reliably prevented.

[0022] As another aspect, it is preferable that the rear suspension cross member is suspended and supported from a total of four fixing points at the front side position and the rear side position of the pair of left and right side beams, and the brackets overlap in the front-rear direction with respect to the pair of left and right fixing points at the rear side position of the rear suspension cross member with the pair of left and right side beams interposed therebetween (protection range 5).

[0023] According to the configuration structure of the power unit and the rear seat in the electric vehicle configured as described above, on the lower side of the floor, the left and right side beams are connected via the rear suspension cross member, and on the upper side of the floor, the brackets on the left and right side beams are connected via the frame member. And the left and right brackets overlap in the front-rear direction with the left and right fixing points at the rear side position of the rear suspension cross member with each side beam interposed therebetween. As a result, since the rear part of the rear suspension cross member, the left and right brackets, and the frame member are connected at positions that are almost the same in the front-rear direction with the left and right side beams interposed therebetween and cooperate with each other to form a rigid structure, the deformation of the rear suspension cross member and the frame member is further suppressed.

[0024] Effect of the Invention

[0025] In the configuration structure of the power unit and the rear seat in the electric vehicle according to the present invention, in the body structure with the rear-wheel drive in which the power unit is arranged above the floor of the vehicle body and the rear seat is further arranged directly above the power unit, it is possible to reliably protect the power unit and prevent damage during a rear collision. Brief Description of the Drawings

[0026] Figure 1 It is a cross-sectional view showing the positional relationship of the rear suspension cross member and the rear seat with respect to the side beam when observing the rear part of the electric vehicle according to the embodiment from the left side.

[0027] Figure 2 It is a cross-sectional view showing the positional relationship of the drive unit and the power unit with respect to the floor when observing the rear part of the electric vehicle from the rear.

[0028] Figure 3 It is a top view showing the arrangement state of the drive unit on the rear suspension cross member.

[0029] Figure 4 It is a top view showing the arrangement state of the power unit on the floor.

[0030] Figure 5 It is a cross-sectional view showing the installation state of the power unit when observing the rear part of the electric vehicle from the left side.

[0031] Figure 6 It is a top view showing the arrangement state of the rear seat on the floor.

[0032] Figure 7 It is a schematic view showing the state in which the rear seat is stored.

[0033] Figure 8 It is a schematic view showing the behavior of the rear seat in the case of a rear collision of another vehicle with a higher vehicle height.

[0034] Figure 9 It is a schematic view showing the behavior of the rear seat in the case of a rear collision of another vehicle with a lower vehicle height. Detailed Description of the Embodiment

[0035] Hereinafter, an embodiment of the configuration structure of the power unit and the rear seat in the electric vehicle embodying the present invention will be described.

[0036] Figure 1 It is a cross-sectional view showing the positional relationship of the rear suspension cross member and the rear seat with respect to the side beam when observing the rear part of the electric vehicle according to the present embodiment from the left side, Figure 2It is a cross-sectional view showing the positional relationship of the drive unit and the power supply unit relative to the floor when observing the rear of the electric vehicle from the rear. Figure 3 It is a top view showing the arrangement state of the drive unit on the rear suspension cross member. In the following description, the front-rear, left-right, and up-down directions are expressed with the driver riding in the vehicle as the main body.

[0037] The electric vehicle 1 of the present embodiment is a hybrid vehicle equipped with a traveling motor 9 described later as a traveling power source and an engine (not shown). A pair of side beams 3l and 3r are provided on the lower surface of the floor 2 constituting the body of the electric vehicle 1, and closed cross-sections are respectively formed between each side beam 3l and 3r and extend in the front-rear direction.

[0038] A rear suspension cross member 4 is disposed below the floor 2, and the left and right sides of the rear suspension cross member 4 are suspended and supported from each side beam 3l and 3r. Specifically, in Figure 3 the top view shown, support members 5fl, 5fr, 5rl, and 5rr (also referred to as fixed points in the following description since they correspond to the fixed points of the present invention) are provided at the front and rear positions of the left and right side beams 3l and 3r, and the left and right front and rear portions of the rear suspension cross member 4 are suspended and supported from each fixed point 5fl, 5fr, 5rl, and 5rr. In addition, the left and right sides of the rear suspension cross member 4 are provided to extend forward from the fixed points 5fl and 5fr at the front side positions, and are respectively fastened to the left and right side beams 3l and 3r by a pair of bolts 6l and 6r.

[0039] The left and right rear wheels 7 are respectively supported via a double-wishbone type suspension (not shown) on the left and right portions of the rear suspension cross member 4 ( Figure 3 only the right side is shown in the figure). Since the structure of this suspension is well known, no detailed description will be given, but this suspension is composed of an upper arm, a lower arm, a toe control link, a spring, a shock absorber, etc. During the running of the electric vehicle 1, in order to overcome the input from the road surface, the driving reaction force on the rear wheel 7, etc., the rear suspension cross member 4 is made of a thick-walled steel plate and has high strength, and is supported by the left and right side beams 3l and 3r having the same high strength.

[0040] Below the floor 2, as the drive unit 8, the traveling motor 9, the inverter 10 integrally provided with the traveling motor 9, and the drive axle 11 functioning as a speed reducer are installed on the rear suspension cross member 4 via the support member 13, and the drive axle 11 is connected to the left and right rear wheels 7 via a pair of left and right drive shafts 12.

[0041] The drive motor 9 for running is drive-controlled by the inverter 10. For example, during power supply control, the DC power from a running battery (not shown) is converted into three-phase AC power by the inverter 10 and supplied to the drive motor 9 for running. The rotation of the drive motor 9 for running is decelerated within the drive axle 11, and the left and right rear wheels 7 are driven via the drive shaft 12. Further, during regeneration control, the rotation of the left and right rear wheels 7 is transmitted to the drive motor 9 for running via the drive shaft 12 and the drive axle 11, and the three-phase AC power generated by power generation through the drive motor 9 for running is converted into DC power by the inverter 10 and used to charge the running battery.

[0042] Figure 4 is a plan view showing the arrangement state of the power supply unit on the floor 2, Figure 5 is a sectional view showing the installation state of the power supply unit when observing the rear part of the electric vehicle 1 from the left side.

[0043] As Figure 4 、 5 shown, an upper front floor cross member 16 and an upper rear floor cross member 17 are provided on the upper surface of the floor 2, and a lower front floor cross member 18 and a lower rear floor cross member 19 are provided on the lower surface of the floor 2. Closed sections are formed between each of the floor cross members 16 to 19 and the lower surface of the floor 2, and they extend in the left-right direction, and both ends thereof are connected to the left and right side beams 3l, 3r.

[0044] On the floor 2, a junction box 21, a charger 22, and a DC-AC inverter 23 are installed as the power supply unit 20 from the left side. As is well known, the junction box 21 is a device that connects various electrical loads such as the running battery and the drive motor 9 for running, the charger 22 is a device that charges the running battery with the power from an external power supply such as a charging station via the charging port 30, and the DC-AC inverter 23 is a device that converts the DC power of the running battery into 100V AC power so that household electricity can be used.

[0045] Figure 5 Illustrating the installation state of the junction box 21, the front surface of the junction box 21 is fixed to the upper front floor cross member 16 by brackets 24 and bolts 25, 26, and the rear surface of the junction box 21 is fixed to the upper rear floor cross member 17 by brackets 27 and bolts 28, 29. A fragile portion 27a having a substantially triangular shape is formed in a bent manner on the bracket 27. When a rear collision occurs from another vehicle, the fragile portion 27a is bent and deformed to absorb the impact. Although not described repeatedly for the charger 22 and the DC-AC inverter 23, they have the same installation state.

[0046] As Figure 4As shown, on the upper side of the floor 2 and in front of the power supply unit 20, the power cord 50 connecting the junction box 21 and the charger 22 is connected to the side surface on the outer side of the vehicle of the junction box 21 and the side surface on the junction box 21 side of the charger 22. Similarly, the power cord 51 connecting the junction box 21 and the DC-AC inverter 23 is connected to the side surface on the outer side of the vehicle of the junction box 21 and the front surface of the DC-AC inverter 23. In addition, as Figure 2 , 5 shown, a terminal block 21a is provided on the lower surface of the junction box 21, and is embedded in the through hole 2a formed in the floor 2 and protrudes downward. One end of the motor side power cord 42 is connected to the rear surface of the terminal block 21a, and the other end of the power cord 42 is connected to the left side surface of the terminal block 10a of the inverter 10.

[0047] Although not shown, a driving battery is disposed in front of the rear suspension cross member 4 on the lower side of the floor 2, and the terminal block 21a of the junction box 21 is connected to the driving battery via the battery side power cord 34. The power exchange between the driving battery, the charger 22, the DC-AC inverter 23, and the inverter 10 of the driving motor 9 is relayed through the junction box 21. For example, the DC power from the driving battery is supplied to the DC-AC inverter 23 via the junction box 21, and is converted into 100V AC power for use in household electrical work. In addition, the AC power supplied from an external power source through a charging station or the like is converted into DC power by the charger 22 and is used to charge the driving battery via the junction box 21. In addition, the power supply control and regeneration control of the above-mentioned driving motor 9 are also performed via the junction box 21.

[0048] As Figure 5 shown, a unit cover 35 in the shape of a four-sided box that opens downward is disposed directly above the power supply unit 20. The front edge 35a and the rear edge 35b of the unit cover 35 formed in a flange shape are fixed to the upper surfaces of the upper front floor cross member 16 and the upper rear floor cross member 17 by bolts 36 and nuts 37, and the power supply unit 20 is covered from above by the unit cover 35. The unit cover 35 is made by bending a steel plate, and although not shown, a large number of ribs extending in the front-rear direction are formed to improve the strength.

[0049] Figure 6 is a plan view showing the arrangement state of the rear seat on the floor 2.

[0050] As Figure 1 , 2As shown in FIGS. 5 and 6, a retractable third-row seat 39 (equivalent to the rear seat of the present invention, also referred to as the rear seat in the following description) is disposed directly above the unit cover 35, and a storage recess 40 for storing the rear seat 39 is formed at a position behind the rear seat 39 on the floor 2. The bases of the brackets 42l and 42r, which are substantially triangular in side view, are respectively fixed to the left and right side beams 3l and 3r by a pair of front and rear bolts 41, and a frame member 43 made of a pipe is spanned between the tops of the left and right brackets 42l and 42r in the left-right direction, and its both ends are respectively fixed to the brackets 42l and 42r.

[0051] As Figure 1 shown, the frame member 43 is disposed at a front position at a distance dimension L1 from the rear end of the rear suspension cross member 4 in the front-rear direction, at a front position at a distance dimension L2 from the fixing points 5rl and 5rr at the rear side position, and at a rear position at a distance dimension L3 from the rear end of the unit cover 35. In addition, in the up-down direction, the frame member 43 is disposed at an upper position at a distance dimension L4 from the uppermost part of the power unit 20.

[0052] In addition, since the front-rear positions of the frame member 43 and the fixing points 5rl and 5rr at the rear side position are only separated by a small dimension L2 as described above, the left and right brackets 42l and 42r supporting the frame member 43 are disposed at overlapping positions in the front-rear direction with respect to the fixing points 5rl and 5rr across the left and right side beams 3l and 3r.

[0053] Although not shown, the frame member 43 configured in this way supports the rear part of the seat cushion 39a of the rear seat 39 throughout the left-right direction, whereby the rear part of the rear seat 39 is supported from the side beams 3l and 3r via the frame member 43 and the left and right brackets 42l and 42r. In addition, the front part of the seat cushion 39a is supported by brackets (not shown) on the left and right wheelhouse inner members via a latch mechanism not shown, and when the latch mechanism is released, the front part of the seat cushion 39a is separated from the brackets on the wheelhouse inner members and can rotate about the frame member 43 as an axis. In addition, although not shown, the seat back 39b is supported so as to be rotatable relative to the seat cushion 39a, and is fixed at a desired angle by a locking mechanism not shown. In addition, a headrest 39c is connected to the upper part of the seat back 39b, and the headrest 39c can also rotate relative to the seat back.

[0054] With the above structure, the rear seat 39 can be folded about the frame member 43. Based on Figure 5To describe the storage process, first, the headrest 39c is folded forward and overlapped with the seat back 39b. Then, after unlocking the locking mechanism of the seat back 39b, the seat back 39b is folded forward and overlapped with the seat cushion 39a. Thus, the rear seat 39 is folded into three layers, and the latch mechanism of the seat cushion 39a is released, so that the entire rear seat 39 is flipped backward with the frame member 43 as the axis center. As Figure 5 shown by the double-dot dash line in the figure, the rear seat 39 is housed in the storage recess 40 on the floor 2, and the bottom surface of the seat cushion 39a is in the same plane as the trunk board surface 44. When the rear seat 39 in the stored state is unfolded and can be used, the reverse process is adopted.

[0055] The frame member 43 needs to have sufficient strength to support the weight of the rear seat 39 and the weight of the occupant and correctly guide the storage and unfolding of the rear seat 39, and the left and right brackets 42l, 42r that support these components also need sufficient strength. To meet the above requirements, the frame member 43 and the brackets 42l, 42r are not only made of thick-walled materials, but also the brackets 42l, 42r are vertically provided on the left and right side beams that function as the body structure. In this way, the frame member 43 is originally configured as a strong structure, and in this embodiment, in order to protect the power unit 20 by using the frame member 43 in a rear collision, based on Figure 1 the above-mentioned front-rear direction and up-down direction position settings, hereinafter, the protective effect of the power unit 20 in a rear collision will be described.

[0056] Since the rear seat 39 is disposed directly above the power unit 20 and the rear part of the seat cushion 39a of the rear seat 39 is supported by the frame member 43, the frame member 43 is located behind the power unit 20. And, since the rear end of the rear suspension cross member 4 is located behind the frame member 43 by a distance dimension L1, in a rear collision, the other vehicle that deforms the rear part of the floor 2 and invades forward first collides with the rear end of the rear suspension cross member 4. Since the rear suspension cross member 4 itself has high strength and is suspended and supported from the left and right side beams 3l, 3r that also have high strength, the deformation of the rear suspension cross member 4 is suppressed and the input from the other vehicle is alleviated. In a strong rear collision, there may also be a situation where the other vehicle further invades forward and collides with the frame member 43. However, the forward deformation of the frame member 43 that functions as a strong structure as described above, such as forward bending deformation, etc., is suppressed to the minimum, thereby further alleviating the input from the other vehicle.

[0057] In this way, first, the intrusion of other vehicles is blocked by the rear end of the rear suspension cross member 4 that extends rearward away from the rear seat 39. In the case where the intrusion of other vehicles cannot be blocked only by the rear end of the rear suspension cross member 4, in addition to the rear suspension cross member 4, the frame member 43 is also used to block the entry of other vehicles. As a result, the input from other vehicles is mitigated in two stages.

[0058] Specifically, when an other vehicle collides with the rear suspension cross member 4, from this moment on, the input is absorbed by the deformation of the rear suspension cross member 4. The other vehicle deforms the rear suspension cross member 4 while approaching the frame member 43. Since the input is continuously absorbed by deforming the rear suspension cross member 4 during this period, in most cases, the residual input at the time when the other vehicle collides with the frame member 43 is small enough. In other words, the input absorbed for the protection of the power unit 20 is small enough. And, after the collision with the frame member 43, in addition to the deformation of the rear suspension cross member 4, the frame member 43 also starts to deform, whereby the residual input is reliably absorbed. Therefore, it is possible to prevent the collision of other vehicles with the power unit 20, and further prevent the breakage of the power unit 20 caused by the collision.

[0059] Of course, for the occupants sitting on the rear seat 39, the same as the case of the power unit 20, by mitigating the input in two stages in the order of the rear end of the rear suspension cross member 4 and the frame member 43, it is possible to reliably protect the occupants from a rear collision.

[0060] In particular, in the present embodiment, the left and right brackets 42l, 42r that support the frame member 43 are respectively disposed at positions that overlap in the front-rear direction with respect to the fixing points 5rl, 5rr across the left and right side beams 3l, 3r. And, below the floor, the left and right side beams 3l, 3r are connected via the rear suspension cross member 4, and above the floor, the brackets 42l, 42r on the left and right side beams 3l, 3r are connected via the frame member 43. Therefore, the rear portion of the rear suspension cross member 4 (the portions of the fixing points 5rl, 5rr), the left and right brackets 42l, 42r, and the frame member 43 are connected at positions that are almost the same in the front-rear direction across the left and right side beams 3l, 3r, and cooperate with each other to form a strong structure. This factor also greatly contributes to suppressing the deformation of the rear suspension cross member 4 and the frame member 43 during a rear collision, and further greatly contributes to the protection of the power unit 20.

[0061] In addition, a frame member 43 is disposed at an upper position with respect to a distance dimension L4 from the uppermost part of the power supply unit 20. As a result, the rear end of the rear suspension cross member 4 is disposed below the power supply unit 20, and the frame member 43 is disposed above. For example, when the frame member 43 is disposed below the uppermost part of the power supply unit 20, when the intrusion height of another vehicle is high, not only the rear end of the rear suspension cross member 4 but also the frame member 43 does not collide head-on with another vehicle, and there is a possibility of colliding with the power supply unit 20 without the input being alleviated. By disposing the frame member 43 and the rear suspension cross member 4 above and below the power supply unit 20, it is possible to reliably collide another vehicle with the rear suspension cross member 4 and the frame member 43 regardless of the intrusion height before colliding with the power supply unit 20, and this factor also greatly contributes to the protection of the power supply unit 20.

[0062] Moreover, since the frame member 43 is located above the power supply unit 20, even if the frame member 43 deforms or moves toward the power supply unit 20 due to the intrusion of another vehicle, it is possible to prevent the frame member 43 from interfering with the power supply unit 20, and thus it is possible to more reliably protect the power supply unit 20 and prevent breakage.

[0063] On the other hand, the front edge 35a and the rear edge 35b of the unit cover 35 are fixed to the upper surfaces of the upper front floor cross member 16 and the upper rear floor cross member 17 that are connected to the left and right side beams 3l and 3r at both ends, and the unit cover 35 covers the battery unit 20 from above. As a result, the front edge 35a and the rear edge 35b of the unit cover 35 are restricted in position displacement because they are fixed to the firm upper front floor cross member 16 and the upper rear floor cross member 17, and thus, in combination with a large number of ribs, the strength of the unit cover 35 in the front-rear direction is improved.

[0064] And, the frame member 43 is disposed at a rear side position with respect to a distance dimension L3 from the rear end of the unit cover 35. Therefore, since the input from another vehicle is alleviated by the collision with the rear end of the rear suspension cross member 4, alleviated by the collision with the frame member 43, and alleviated by the collision with the unit cover 35 having high strength in the front-rear direction, it is possible to further reliably prevent another vehicle from colliding with the power supply unit 20.

[0065] Moreover, the disposition of the frame member 43 at the upper side position based on the dimension L4 also functions to protect the power supply unit 20 during a rear collision in a state where the rear seat 39 is stored.

[0066] Figure 7 is a schematic view showing a state in which the rear seat 39 is stored, Figure 8 is a schematic view showing the behavior of the rear seat 39 in the case of a rear collision by another vehicle A having a high vehicle height. Figure 9This is a schematic diagram showing the behavior of the rear seat 39 in the case of a rear collision by another vehicle B with a relatively low vehicle height.

[0067] In the stored state of the rear seat 39, before another vehicle that deforms the rear part of the floor 2 and intrudes forward due to a rear collision collides with the rear end of the rear suspension cross member 4, it first collides with the rear seat 39 within the storage recess 40. The behavior (deformation, movement, etc.) of the rear seat 39 at this time varies depending on the collision conditions such as the intrusion height of another vehicle. For example, in the case of another vehicle A such as a bus with a relatively high vehicle height, due to the relatively high intrusion height, there are more cases of a frontal collision with the rear seat 39. Since the forward movement of the rear seat 39 is restricted by the rigid frame member 43 at this time, from Figure 7 the normal stored state shown, as Figure 8 shown, it maintains its posture within the storage recess 40 and is crushed in the front-rear direction. Along with this crushing, the input from another vehicle A is absorbed through the polyurethane material inside the rear seat 39, etc. Therefore, since the input at the time when another vehicle A subsequently collides with the rear end of the rear suspension cross member 4 or the input at the time of collision with the frame member 43 is mitigated, this factor also greatly contributes to the protection of the power unit 20.

[0068] In addition, for example, in the case of another vehicle B such as a passenger car with a relatively low vehicle height, due to the relatively low intrusion height, the rear part of the floor 2 is lifted and there are more cases of collision with a position lower than the rear seat 39. The rear seat 39 at this time, from Figure 7 the normal stored state shown, as Figure 9 shown, bounces up by rotating around the frame member 43 due to the collision of another vehicle B. Since the frame member 43 as the rotation center is disposed at an upper position at a distance dimension L4 from the power unit 20, all parts of the rear seat 39 after bouncing up are located above the power unit 20. As a result, a collision of the rear seat 39 against the power unit 20 is reliably prevented, and this factor also greatly contributes to the protection of the power unit 20.

[0069] Furthermore, the behavior of the rear seat 39 during a rear collision is not limited to being clearly shown as being crushed or bouncing up. For example, when both behaviors occur simultaneously, their respective effects are achieved together.

[0070] As described above, although the description of the embodiment has been completed, the form of the present invention is not limited to this embodiment. For example, in the above embodiment, the configuration structure of the power unit 20 and the rear seat 39 in the hybrid vehicle 1 is embodied, but as long as it is an electric vehicle equipped with a power unit 20 and a rear seat 39, arbitrary changes can be made. For example, it can also be applied to an electric vehicle equipped with an electric motor as a driving power source.

[0071] In addition, in the above-described embodiment, the drive motor 9 for traveling, the inverter 10, and the drive axle 11 are disposed on the rear suspension cross member 4 as a drive unit, and the junction box 21, the charger 22, and the DC-AC inverter 23 are disposed above the floor 2 as the power supply unit 20. However, their types and arrangements are not limited thereto. For example, the arrangement of the drive motor 9 for traveling, the inverter 10, and the drive axle 11 may be changed, or the inverter 10 may be disposed above the floor 2 as one of the power supply units 20.

[0072] In addition, in the above-described embodiment, the rear seat 39 is configured as a foldable third-row seat, but it is not limited thereto. For example, it may be a fixed rear seat without a folding function, and in the case of an electric vehicle without a third-row seat, the second-row seat may be used as the rear seat.

[0073] Reference Signs

[0074] 1 Electric vehicle

[0075] 2 Floor

[0076] 3l, 3r Side beams

[0077] 4 Rear suspension cross member

[0078] 5fl, 5fr, 5rl, 5rr Mounting points

[0079] 7 Rear wheels

[0080] 8 Drive unit

[0081] 9 Drive motor for traveling

[0082] 16 Upper front floor cross member

[0083] 17 Upper rear floor cross member

[0084] 20 Power supply unit

[0085] 21 Junction box

[0086] 35 Unit cover

[0087] 35a Leading edge

[0088] 35b Trailing edge

[0089] 39 Rear seat

[0090] 40 Storage recess

[0091] 42l, 42r Brackets

[0092] 43 Frame member

Claims

1. A configuration structure of a power supply unit and a rear seat in an electric vehicle, characterized in that, The electric vehicle includes: A rear suspension cross member, which is located below the floor of the vehicle body. The rear suspension cross member is suspended and supported by a pair of left and right side beams extending in the front-rear direction, and supports the left and right rear wheels via a suspension; A drive unit, which is installed on the rear suspension cross member below the floor and at least includes a traveling motor that drives the left and right rear wheels; And A power supply unit, which is installed above the floor and at least includes a junction box that relays power from a traveling battery and supplies the power to the traveling motor; and A rear seat, which is disposed directly above the power supply unit, The rear portion of the seat cushion of the rear seat is supported by a frame member that extends in the left-right direction between brackets, and the brackets are provided on the pair of left and right side beams on the upper side of the floor, The entire frame member is disposed at a rear side position relative to the rear end of the power supply unit and at a front side position relative to the rear end of the rear suspension cross member.

2. The configuration structure of the power supply unit and the rear seat in the electric vehicle according to claim 1, characterized in that The entire frame member is disposed at an upper side position relative to the power supply unit.

3. The configuration structure of the power supply unit and the rear seat in the electric vehicle according to claim 1, characterized in that The floor forms a storage recess at a position behind the rear seat, The seat cushion of the rear seat is supported so as to be rotatable about the frame member as an axis center, and the seat back of the rear seat is supported so as to be rotatable relative to the seat cushion. And in a state where the seat back is rotated to coincide with the seat cushion, by turning the entire rear seat about the frame member as an axis center backward, the seat cushion can be received in the storage recess, The entire frame member is disposed at an upper side position relative to the power supply unit.

4. The configuration structure of the power supply unit and the rear seat in the electric vehicle according to any one of claims 1 to 3, characterized in that, It further includes: A front floor cross member and a rear floor cross member, which are respectively formed on the upper surface of the floor extending in the left-right direction, and the left and right ends of the front floor cross member and the rear floor cross member are respectively connected to the pair of left and right side beams; and A unit cover, the front edge of which is fixed to the front floor cross member, the rear edge of which is fixed to the rear floor cross member, and the unit cover covers the power supply unit from above, The entire frame member is disposed at a rear side position relative to the unit cover.

5. The configuration structure of the power supply unit and the rear seat in the electric vehicle according to any one of claims 1 to 3, characterized in that The rear suspension cross member is suspended and supported from a total of four fixing points at the front side position and the rear side position of the pair of left and right side beams, The brackets overlap in the front-rear direction with respect to the pair of left and right fixing points at the rear side position of the rear suspension cross member respectively with the pair of left and right side beams interposed therebetween.

6. The configuration structure of the power supply unit and the rear seat in the electric vehicle according to claim 4, characterized in that The rear suspension cross member is suspended and supported from a total of four fixing points at the front side position and the rear side position of the pair of left and right side beams, The left and right pair of fixing points at the rear side position of the bracket relative to the rear suspension cross member overlap in the front-rear direction with the left and right pair of side beams interposed therebetween.

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