JP2019018686A - Vehicle body structure - Google Patents

Abstract

A vehicle body structure capable of suppressing damage to a battery unit at the time of a vehicle collision is obtained.
A rear suspension member 26 attached to a rear side member 28, a motor unit 16 disposed on the vehicle lower side of the rear suspension member 26, and a battery unit provided on the inner side in the vehicle front-rear direction with respect to the motor unit 16. 14. The motor unit 16 is attached to the rear suspension member 26 by a fastener 27, and this attachment is set to a lower attachment strength than the attachment strength of the rear suspension member 26 to the rear side member 28. Therefore, at the time of a vehicle collision, the fastening by the fastener 27 is released, and the motor unit 16 is dropped from the rear suspension member 26 to the vehicle lower side to suppress the motor unit 16 from interfering with the battery unit 14. Damage to the battery unit 14 at the time can be suppressed.
[Selection] Figure 3

Description

  The present invention relates to a vehicle body structure.

  Patent Document 1 below discloses a battery mounting structure for an electric vehicle. This vehicle is provided with a battery unit on the vehicle lower side of the passenger compartment. The battery unit has an end in the vehicle width direction coupled to the vehicle body member, and an end on the front side of the vehicle is fixed to the front suspension member. Thus, the torsional rigidity of the vehicle body is improved using the battery unit.

JP 2012-91635 A

  By the way, in recent years, it is required to extend the cruising distance of an electric vehicle, and in order to cope with this, it is necessary to enlarge the battery unit. In order to reduce the influence on the passenger compartment in increasing the size, it is conceivable to expand the battery unit in the vehicle front-rear direction. However, if the battery unit is expanded in the vehicle front-rear direction, the distance between the power unit and the battery unit is increased. Therefore, there is a possibility that the power unit that is displaced by receiving a collision load at the time of a vehicle collision comes into contact with the battery unit and damages the battery unit. The prior art has room for improvement in this regard.

  In view of the above facts, an object of the present invention is to obtain a vehicle body structure capable of suppressing damage to a battery unit at the time of a vehicle collision.

  According to a first aspect of the present invention, there is provided a vehicle body structure including a side member extending substantially in the vehicle front-rear direction, a suspension member attached to the side member, and a power unit disposed on the vehicle lower side of the suspension member. A battery unit disposed at a position overlapping the power unit when viewed from the front of the vehicle and spaced apart from the power unit inward in the vehicle front-rear direction, and a mounting strength lower than the mounting strength of the suspension member to the side member And a fastener for attaching the power unit to the suspension member.

  According to the first aspect of the present invention, the side member extending substantially in the vehicle front-rear direction, the suspension member attached to the side member, the power unit disposed on the vehicle lower side of the suspension member, and the vehicle front view The battery unit is disposed at a position overlapping with the power unit and spaced apart from the power unit inward in the vehicle front-rear direction. The power unit is attached to the suspension member by a fastener, and this attachment is set to an attachment strength lower than the attachment strength of the suspension member to the side member. Therefore, when the power unit receives a collision load and tries to displace to the battery unit side at the time of a vehicle collision, the fastening by the fastener is released and the power unit can be dropped from the suspension member to the vehicle lower side. Thereby, it is possible to suppress the power unit from interfering with the battery unit.

  A vehicle body structure according to a second aspect of the present invention is the vehicle body structure according to the first aspect, wherein the power unit is attached to the suspension member via a mount member, and the fastener includes the power unit and the mount member. And a second fastener for fastening the mount member and the suspension member.

  According to the second aspect of the present invention, the power unit is attached to the suspension member via the mount member, and the fastener includes the first fastener for fastening the power unit and the mount member, the mount member, and the suspension member. And a second fastener for fastening together. Therefore, since it is possible to adjust the mounting strength of each of the first fastener and the second fastener, it is possible to reliably hold the power unit that is relatively heavy and generates a large torque to the suspension member in a normal state. In addition, the power unit can be more reliably detached from the suspension member to the vehicle lower side in the event of a vehicle collision.

  A vehicle body structure according to a third aspect of the present invention is the vehicle body structure according to the second aspect, wherein the first fastener includes a bolt whose longitudinal direction is substantially perpendicular to the vehicle longitudinal direction.

  According to the invention described in claim 3, the first fastener is configured to include a bolt whose longitudinal direction is substantially perpendicular to the vehicle longitudinal direction. Accordingly, when a collision load is input to the vehicle from the vehicle front-rear direction outside to the vehicle front-rear direction inner side and the power unit is to be displaced toward the battery unit, the direction of the first fastener bolt is perpendicular to the longitudinal direction. The collision load is input to That is, since the collision load acts in the direction in which the bolt of the first fastener is easily broken, the power unit can be more easily dropped from the suspension member to the vehicle lower side.

  A vehicle body structure according to a fourth aspect of the present invention is the vehicle body structure according to the second or third aspect, wherein the second fastener includes a bolt whose longitudinal direction is substantially perpendicular to the vehicle longitudinal direction. Has been.

  According to invention of Claim 4, the 2nd fastener is comprised including the volt | bolt which makes the direction orthogonal to a vehicle front-back direction a longitudinal direction. Accordingly, when a collision load is input to the vehicle from the vehicle longitudinal direction outside to the vehicle longitudinal direction inner side and the power unit attempts to displace to the battery unit side, the direction of the second fastener bolt is perpendicular to the longitudinal direction. The collision load is input to That is, since the collision load acts in the direction in which the bolt of the second fastener is easily broken, the power unit can be more easily dropped from the suspension member to the vehicle lower side.

  The vehicle body structure according to the first aspect of the present invention has an excellent effect that damage to the battery unit at the time of a vehicle collision can be suppressed.

  The vehicle body structure according to the second aspect of the present invention has an excellent effect that damage to the battery unit at the time of a vehicle collision can be more reliably suppressed.

  The vehicle body structure according to the third and fourth aspects of the present invention has an excellent effect that the damage to the battery unit at the time of a vehicle collision can be further suppressed.

It is a schematic sectional drawing which shows the vehicle body structure which concerns on one Embodiment. It is an expanded sectional view which expands and shows the Z section in FIG. It is sectional drawing which shows the state cut | disconnected along the AA in FIG. It is an expanded sectional view which shows the state after a vehicle collision with respect to FIG.

  Hereinafter, an embodiment of a vehicle body structure according to the present invention will be described with reference to FIGS. 1 to 4, the arrow FR indicates the front side in the vehicle longitudinal direction, the arrow OUT indicates the vehicle width direction outside, and the arrow UP indicates the vehicle vertical direction upper side.

  As shown in FIG. 1, a vehicle 12 to which the vehicle body structure 10 is applied is an electric vehicle that travels by an electric motor (motor unit 16) as a power unit that is driven by power supplied from a battery unit 14 to be described later. A floor panel 18 is provided. On both sides on the outer side in the vehicle width direction with respect to the floor panel 18, rockers (not shown) (also referred to as “side sills”) are arranged in a pair on the left and right with the vehicle longitudinal direction as the longitudinal direction. The terminal part of the floor panel 18 is joined to the upper part of the rocker by spot welding.

  The battery unit 14 is provided under the vehicle floor, that is, between the vehicle lower side of the floor panel 18 and the pair of left and right rockers. The battery unit 14 is disposed at a position overlapping the motor unit 16 when viewed from the front of the vehicle, the front end portion 20 is disposed at a position corresponding to the dash panel 22, and the rear end portion 24 is disposed relative to the motor unit 16. It is formed in a substantially rectangular box shape spaced apart in the front-rear direction, and is attached to a rocker as an example.

  Rear side members 28 (see FIG. 3) are coupled to the rear ends of the pair of left and right rockers. As shown in FIG. 3, a rear floor panel 19 constituting a floor surface of the rear portion of the vehicle is provided between the pair of left and right rear side members 28, and ends of the rear floor panel 19 in the vehicle width direction are respectively rear side members. It couple | bonds with 28 vehicle width direction inner surface.

  The vehicle front side end portion of the rear floor panel 19 is coupled to the upper side surface of the floor cross member 21 extending in the vehicle width direction. The floor cross member 21 is formed in a prismatic shape, and the vehicle front side end is coupled to the rear end of the floor panel 18.

  As shown in FIG. 1, a rear suspension member 26 is disposed on the vehicle lower side of the pair of left and right rear side members 28 and between the pair of left and right rear tires 30. The rear suspension member 26 includes a front cross member 32 extending in the vehicle width direction, a pair of left and right side rails (not shown) extending from both ends of the front cross member 32 in the vehicle width direction to the vehicle rear side, A rear cross member 34 that connects the rear ends of the pair of left and right side rails (note that the rear cross member 34 is not shown in FIG. 4) and has a space S in the center when viewed from above the vehicle. It is formed in a rectangular shape. The rear suspension member 26 is attached to the bush 33 by fastening bolts 35 inserted from the vehicle lower side in a state of being suspended from the rear side member 28, and a suspension for suspending the left and right rear tires 30. A suspension arm and a stabilizer (both not shown) are attached.

  A motor unit 16 is disposed in the space S of the rear suspension member 26. The motor unit 16 is positioned between a pair of left and right side rails in the rear suspension member 26, and is fastened to the rear suspension member 26 via a first fastener 27A as a fastener 27, as shown in FIG. Has been. Specifically, a pair of left and right mounting brackets 29 that are part of the mounting member are attached to both ends of the motor unit 16 in the vehicle width direction via a plurality of second fasteners 27B. The second fastener 27 </ b> B has a bolt 31 having a longitudinal direction substantially in the vehicle width direction, and the bolt 31 is formed in a through-hole (not shown) formed in the mounting bracket 29 in the substantially vehicle width direction. It is configured to be inserted and screwed into the motor unit 16. In addition, a substantially cylindrical support mount 36 that includes an elastic member and has a substantially vehicle vertical direction as an axial direction is attached to an outer end portion of the mounting bracket 29 in the vehicle width direction. Yes. A support mount 36 is fastened to the lower surface of the front cross member 32 of the rear suspension member 26 from the vehicle lower side of the rear suspension member 26 by a first fastener 27A. The first fastener 27A is configured by a bolt 38 having a longitudinal direction substantially in the vehicle vertical direction and a nut 40 that is screwed with the bolt 38, and is formed in the support mount 36 and on the lower surface of the front cross member 32 (not shown). A bolt 38 inserted into the through hole is screwed with a nut 40.

  The attachment strength of the support mount 36 to the rear suspension member 26 by fastening the first fastener 27A described above is set lower than the attachment strength of the bolt 35 to the rear side member 28 of the rear suspension member 26. . That is, the mounting strength (bolt strength) is set lower than the mounting strength of the rear suspension member 26 to the rear side member 28 by adjusting the diameter, material, and number of the bolts 31 in the first fastener 27A in advance. Similarly, the mounting strength of the mounting bracket 29 to the motor unit 16 by fastening the second fastener 27B is set lower than the mounting strength by fastening the bolt 35 to the rear side member 28 of the rear suspension member 26. . The number of bolts 38 of the first fastener 27A, the bolt 31 of the second fastener 27B, and the bolt 35 of the rear suspension member 26 are different from each other. Here, all the mounting strengths of the plurality of bolts 38 of the first fastener 27A are set to be lower than all the mounting strengths of the plurality of bolts 35 of the rear suspension member 26. Similarly, all the mounting strengths of the plurality of bolts 31 of the second fastener 27B are set to be lower than all the mounting strengths of the plurality of bolts 35 of the rear suspension member 26.

  Further, the motor unit 16 is attached to the side surface of the rear cross member 34 shown in FIG. 2 via a support mount (both not shown) formed of a bracket and an elastic member from the front side of the vehicle. The motor unit 16 can rotate a pair of left and right rear tires 30 (see FIG. 1) via an output shaft (not shown).

  Next, the operation and effect of this embodiment will be described.

  In the present embodiment, as shown in FIG. 2, a rear side member 28 extending substantially in the vehicle front-rear direction, a rear suspension member 26 attached to the rear side member 28, and a rear suspension member 26 provided at the rear of the vehicle. A motor unit 16 disposed on the vehicle lower side, and a battery unit 14 disposed at a position overlapping the motor unit 16 when viewed from the front of the vehicle and spaced apart from the motor unit 16 in the vehicle front-rear direction. Have. As shown in FIG. 3, the motor unit 16 is attached to the rear suspension member 26 by a fastener 27. This attachment is set to a lower attachment strength than the attachment strength of the rear suspension member 26 to the rear side member 28. Has been. Therefore, as shown in FIG. 4, when the motor unit 16 receives a collision load from the collision body C and is displaced to the battery unit 14 side at the time of a vehicle collision, the fastening by the fastener 27 is released and the motor unit 16 is The rear suspension member 26 can be detached from the vehicle lower side. Thereby, it is possible to suppress the motor unit 16 from interfering with the battery unit 14. Thus, damage to the battery unit 14 at the time of a vehicle collision can be suppressed.

  The motor unit 16 is attached to the rear suspension member 26 via a support mount 36, and the fastener 27 includes a first fastener 27 </ b> A that fastens the motor unit 16 and the support mount 36, A second fastener 27B for fastening the rear suspension member 26 is provided. Therefore, since it is possible to adjust the attachment strength with each of the first fastener 27A and the second fastener 27B, the first fastener 27A and the second fastener are considered in consideration of the collision mode, the weight of the motor unit 16, and the like. By adjusting the mounting strength of the tool 27B, the motor unit 16 that generates a relatively large weight and a large torque in the normal state can be securely held to the rear suspension member 26, and the motor unit 16 can be held in a vehicle collision. The rear suspension member 26 can be more reliably detached from the vehicle lower side. Thereby, the damage of the battery unit 14 at the time of a vehicle collision can be suppressed more reliably.

  Further, the first fastener 27A includes a bolt whose longitudinal direction is substantially perpendicular to the vehicle longitudinal direction. Accordingly, when a collision load is input to the vehicle from the vehicle front-rear direction outer side toward the vehicle front-rear direction inner side, the motor unit 16 tends to be displaced toward the battery unit 14, and the bolt 38 of the first fastener 27A is easily broken. Since the collision load acts in the direction, the motor unit 16 can be more easily dropped from the rear suspension member 26 to the vehicle lower side.

  Furthermore, the second fastener 27B includes a bolt whose longitudinal direction is substantially perpendicular to the vehicle longitudinal direction. Therefore, when a collision load is input to the vehicle from the vehicle front-rear direction outer side toward the vehicle front-rear direction inner side to cause the motor unit 16 to be displaced toward the battery unit 14, the bolt 31 of the second fastener 27B has a longer length. A collision load is input in a direction orthogonal to the direction. That is, since the collision load acts in the direction in which the bolt 31 of the second fastener 27B is easily broken, the motor unit 16 can be more easily dropped from the rear suspension member 26 to the vehicle lower side. By these, damage to the battery unit 14 at the time of a vehicle collision can be further suppressed.

  Further, the first fastener 27A and the second fastener 27B are configured to include bolts 31 and 38, respectively. That is, the motor unit 16 and the support mount 36 are fastened using the general-purpose bolt 31, and the support mount 36 and the rear suspension member 26 are fastened using the general-purpose bolt 38. Therefore, damage to the battery unit 14 at the time of a vehicle collision can be suppressed while suppressing costs.

  Furthermore, as shown in FIG. 4, the vehicle deformation stroke ΔS can be ensured by displacing the motor unit 16 while dropping from the rear suspension member 26 to the vehicle lower side. Therefore, a part of the collision load is absorbed by the vehicle deformation stroke ΔS, and accordingly, the proof strength of the rear side member 28 can be reduced and the weight of the vehicle can be reduced.

  Furthermore, since the motor unit 16 is attached to the rear suspension member 26 from the lower side of the vehicle, the front cross member 32 of the rear suspension member 26 can be arranged substantially linearly in the vehicle width direction. Therefore, the weight of the vehicle can be further reduced by simplifying the structure.

  In the above-described embodiment, the motor unit 16 is provided between the rear portion of the vehicle 12, that is, the pair of left and right rear tires 30. However, the present invention is not limited to this, and the front portion of the vehicle (for example, FIG. A front suspension member (both not shown) is attached to a front side member as a side member provided between a pair of left and right front tires 68 shown in FIG. 2 and a motor unit 16 is attached to the front suspension member from the vehicle lower side. It is good.

  Moreover, although the 1st fastener 27A and the 2nd fastener 27B are comprised including the volt | bolts 31 and 38, respectively, the structure comprised by other members, such as not only this but a rivet, may be sufficient. Furthermore, although the fastener 27 is made into the structure provided with the 1st fastener 27A and the 2nd fastener 27B, it is not restricted to this, Only one of the 1st fastener 27A or the 2nd fastener 27B is used. It is good also as a structure provided, and it is good also as a structure fastened to other site | parts in one place or three or more multiple places.

  Furthermore, although the bolt 38 of the first fastener 27A is configured to have the vehicle vertical direction as the longitudinal direction, the configuration is not limited thereto, and the longitudinal direction may be approximately the vehicle width direction. That is, the bolt 38 may have a configuration in which the longitudinal direction is set to another direction substantially orthogonal to the vehicle front-rear direction. Similarly, the bolt 31 of the second fastener 27B is configured to have a substantially vehicle width direction as a longitudinal direction. However, the configuration is not limited thereto, and the longitudinal direction may be a substantially vehicle vertical direction. That is, the bolt 31 may have a configuration in which the longitudinal direction is set to another direction substantially orthogonal to the vehicle front-rear direction.

  The embodiment of the present invention has been described above, but the present invention is not limited to the above, and various modifications other than those described above can be implemented without departing from the spirit of the present invention. Of course.

10 Body structure 14 Battery unit 16 Motor unit (power unit)
26 Rear suspension member (suspension member)
27 Fastener 27A First Fastener 27B Second Fastener 28 Rear Side Member (Side Member)
29 Mounting bracket mount member)
31 Bolt 36 Support mount (mounting member)
38 volts

Claims (4)

Side members extending substantially in the vehicle longitudinal direction;
A suspension member attached to the side member;
A power unit disposed on the vehicle lower side of the suspension member;
A battery unit that is disposed at a position overlapping the power unit in a front view of the vehicle and is spaced from the power unit inward in the vehicle front-rear direction;
A fastener for attaching the power unit to the suspension member at a lower attachment strength than the attachment strength of the suspension member to the side member;
A vehicle body structure. The power unit is attached to the suspension member via a mount member,
The fastener includes a first fastener that fastens the power unit and the mount member, and a second fastener that fastens the mount member and the suspension member.
The vehicle body structure according to claim 1. The first fastener includes a bolt whose longitudinal direction is substantially perpendicular to the vehicle longitudinal direction.
The vehicle body structure according to claim 2. The second fastener includes a bolt whose longitudinal direction is substantially perpendicular to the vehicle longitudinal direction.
The vehicle body structure according to claim 2 or claim 3.