Vehicle structure

Abstract

To provide a vehicle structure in which a strength of installing a motor unit is improved by means of a simple constitution so that deviation of the motor unit to a vehicle front side can be effectively suppressed at the time of a rear collision of the vehicle.SOLUTION: A vehicle structure A includes a motor unit 2 for driving a drive shaft which is positioned at a vehicle rear side of a step part 43 of a floor part 4 and arranged below a rear floor part 4r. The vehicle structure includes: a floor cross member 11 which is joined with a lower surface side of at least one of a step part 43 and a front floor part 4f to extend in a vehicle width direction; and a reinforcement member 5 in which a plurality of portions where the floor cross member 11, a rear face wall part 43a of the step part 43, and a rear side member 10 are respectively joined are sequentially connected. The reinforcement member 5 is an object part for installing the motor unit 2.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a vehicle structure such as an automobile.

Background Art

[0002] As a specific example of a vehicle structure, there is one described in Patent Document 1. In the vehicle structure described in the same document, a motor unit used in an electric vehicle, a hybrid electric vehicle, etc. is attached to the lower surface side of the floor portion of the vehicle. The motor unit has a motor portion and a gear portion, and is configured such that the output from the motor portion can be transmitted to a pair of left and right drive shafts via the gear portion. In addition, a stepped portion is provided in the floor portion of the vehicle, and the rear floor portion on the vehicle rear side of this stepped portion is higher than the front floor portion on the vehicle front side. The motor unit is located on the vehicle rear side of the stepped portion and is disposed below the rear floor portion. Since the height of the rear floor portion is increased, it is preferable in securing the arrangement space of the motor unit.

[0003] However, in the above prior art, as described below, there was still room for improvement.

[0004] That is, when designing and manufacturing a vehicle, it is required to enhance the safety at the time of vehicle collision. Here, as one aspect of vehicle collision, there is a rear collision. In the vehicle structure of the above prior art, when a rear collision of the vehicle occurs, there is a possibility that the motor unit may be displaced toward the vehicle front side due to the action of a collision load. Therefore, it is desired to increase the mounting strength of the motor unit and make the above-described displacement amount as small as possible. In an electric vehicle, a hybrid electric vehicle, etc. in which the motor unit is used, a battery may be disposed on the lower surface side of the front floor portion and set in an arrangement close to the vehicle front side of the motor unit. In such a case, it is more strongly desired to appropriately suppress the displacement of the motor unit toward the vehicle front side when a rear collision of the vehicle occurs.

Prior Art Documents

Patent Document

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present invention has been conceived under the circumstances as described above, and an object thereof is to provide a vehicle structure capable of increasing the mounting strength of a motor unit by means of a simple configuration and effectively suppressing displacement of the motor unit toward the front side of the vehicle when a rear - end collision of the vehicle occurs.

Means for Solving the Problems

[0007] To solve the above problems, the present invention takes the following technical means.

[0008] A vehicle structure provided by a first aspect of the present invention is provided in a region closer to the center in the vehicle front - rear direction or a rear - side region of the floor portion of the vehicle, and a step portion that divides the floor portion into a rear floor portion and a front floor portion having a lower height than the rear floor portion, and a motor unit for driving a drive shaft disposed below the rear floor portion so as to be located on the rear - side of the vehicle of this step portion, and a rear side member located on the outer side in the vehicle width direction of this motor unit and extending in the vehicle front - rear direction on the lower surface side of the rear floor portion. The vehicle structure further includes a floor cross - member joined to at least one of the lower surface sides of the step portion or the front floor portion and extending in the vehicle width direction, and a reinforcing member in which a plurality of portions respectively joined to the floor cross - member, the rear surface wall portion of the step portion, and the rear side member are connected in series. The reinforcing member is a portion to which the motor unit is attached. According to such a configuration, the following effects can be obtained.

[0009] According to such a configuration, the following effects can be obtained. That is, the reinforcing member to which the motor unit is to be attached is joined to a predetermined floor cross member, the rear wall portion of the stepped portion of the floor portion, and the rear side member, and the joined portions are connected in series. In other words, this configuration is a configuration in which the floor cross member and the rear side member as vehicle body frame members are bridged and connected using a reinforcing member disposed along the stepped portion. Therefore, the location where the reinforcing member is provided is made into a portion with considerably high strength, and the mounting strength of the motor unit can be effectively increased. As a result, it is possible to appropriately suppress not only ensuring rigidity during normal running of the vehicle but also large displacement of the motor unit toward the front side of the vehicle in the event of a rear-end collision of the vehicle, thereby enhancing safety. When, for example, a battery is mounted on the front side of the vehicle of the motor unit, this is preferable for preventing the motor unit from strongly colliding with the battery. On the other hand, the reinforcing member does not need to be large and bulky, and can be relatively thin and lightweight. Therefore, it is also possible to suitably avoid a significant increase in vehicle weight and manufacturing cost.

[0010] The vehicle structure provided by the second aspect of the present invention is provided in a region closer to the center in the vehicle front-rear direction or a rearward region of the floor portion of the vehicle, and has a step portion that divides the floor portion into a rear floor portion and a front floor portion having a lower height than the rear floor portion, and a motor unit for driving a drive shaft disposed below the rear floor portion so as to be located on the vehicle rearward side of the step portion. A vehicle structure comprising: a floor cross member extending in the vehicle width direction joined to at least one of the lower surface sides of the step portion or the front floor portion; a reinforcing member in which a plurality of portions joined to the rear surface wall portion of the floor cross member, the rear surface wall portion of the step portion, and the lower surface portion of the rear floor portion are connected in series; and a bracket for the motor unit that enables attachment of the motor unit to the reinforcing member. The bracket for the motor unit is overlapped and joined to the lower surface side and the rear surface side of the reinforcing member, and has a front extension portion that extends to the vehicle front side of the reinforcing member and is joined to the lower surface portion of the floor cross member.

[0011] According to such a configuration, the following effects can be obtained. That is, the reinforcing member to which the motor unit is to be attached is joined to the rear wall portion of a predetermined floor cross member, the rear wall portion of the step portion of the floor portion, and the lower surface portion of the rear floor portion, and these joined portions are configured to be connected in series. In other words, this configuration is one in which the floor cross member and the rear floor portion are connected in a bridging manner using a reinforcing member along the step portion. Therefore, the portion where the reinforcing member is provided can be made into a portion with considerably high strength. In addition, the bracket for the motor unit used for attaching the motor unit to the reinforcing member is overlapped and joined to the lower surface side and the rear surface side of the reinforcing member, and in addition, it has a front extension portion that extends to the front side of the vehicle from the reinforcing member and is joined to the lower surface portion of the floor cross member. Therefore, the synergistic reinforcing effect by the combination of both the reinforcing member and the bracket becomes high. As a result, similar to the vehicle structure provided by the first aspect of the present invention, the mounting strength of the motor unit can be effectively increased, and not only the rigidity during normal running of the vehicle can be ensured, but also the displacement of the motor unit to the front side of the vehicle during a rear-end collision of the vehicle can be appropriately suppressed, and the safety can be enhanced. On the other hand, the reinforcing member and the bracket do not need to be provided in a large and bulky state, and can be made into a relatively thin and lightweight portion. Therefore, it is possible to suitably avoid a significant increase in vehicle weight and manufacturing cost.

[0012] Other features and advantages of the present invention will become more apparent from the following description of the embodiments of the invention with reference to the accompanying drawings.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0014] Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

[0015] The vehicle structure A shown in FIGS. 1 to 3 includes a pair of left and right rear side members 10 (the hatched pattern parts, omitted in FIG. 2), a motor unit 2 as a traction motor system, mounting arms 3a to 3c for the motor unit (light ink is appropriately applied to the mounting arms 3a and 3b), a floor portion 4 having a step portion 43, a pair of left and right reinforcing members 5 for mounting the motor unit, a pair of left and right brackets 6 for the motor unit, and a floor cross member 11.

[0016] As well represented in FIGS. 2 and 5, the floor portion 4 includes a front floor portion 4f configured using a front floor panel 40, a rear floor portion 4r configured using a rear floor panel 41, and a step portion 43. The step portion 43 is a portion connecting these two floor portions 4f and 4r so that the rear floor portion 4r is set to a height higher than that of the front floor portion 4f. This step portion 43 further includes an auxiliary panel 42 that connects the front floor panel 40 and the rear floor panel 41 to each other. A part of each of this auxiliary panel 42 and the front floor panel 40 has a rear wall portion 43a and a front wall portion 43b that stand up in the vertical height direction. In the step portion 43, the upper and lower portions of the rear wall portion 43a and the front wall portion 43b are connected to each other, forming a closed cross-section structure portion with high strength. A frame 19 indicated by a virtual line is provided on the vehicle front side of the step portion 43 or above the step portion 43, and a rear seat (not shown) using this frame 19 is installed.

[0017] The pair of rear side members 10 are one of the vehicle body frame members, and are configured using, for example, a hat-shaped cross-section member, and extend in the vehicle longitudinal direction with an interval in the vehicle width direction between them. Each rear side member 10 is joined to the lower surface side of the floor portion 4. In the present embodiment, "joining" is joining by welding unless otherwise indicated. The rear ends of the pair of rear side members 10 are bridged and connected by a lower back frame 13. Although illustration description is omitted, each rear side member 10 has a bent portion corresponding to the step portion 43 of the floor portion 4, and the height of each portion in the vehicle longitudinal direction corresponds to the height of the front floor portion 4f and the rear floor portion 4r.

[0018] The floor cross member 11 is joined to the lower surface side of at least one of the step portion 43 or the front floor portion 4f and extends in the vehicle width direction, and is set to bridge and connect between the pair of rear side members 10. This floor cross member 11 corresponds to a vehicle body frame member, similar to the rear side member 10, and is configured using, for example, a hat-shaped cross-section member.

[0019] The motor unit 2 has a motor section 20 and a gear section 21, and is configured such that the output from the motor section 20 can be transmitted to a pair of left and right drive shafts 28 via the gear section 21. In the figure, reference numeral 9 denotes a rear wheel, and reference numeral 29 denotes a De Dion tube. In the present embodiment, as the rear suspension, a De Dion type suspension, which is one of the axle suspension systems, is adopted, and a pair of wheels 9 are connected and supported by each other by the De Dion tube 29 and receive rotational torque from the pair of drive shafts 28 to rotate drive.

[0020] The battery 98 serving as the driving power source for the motor unit 2 is supported by an appropriate bracket (not shown) and is mounted below the front floor section 4f as shown in FIG. 2. The motor section 20 includes an inverter that receives power supply from the battery 98 and a motor whose rotation is controlled by this inverter. The gear section 21 includes a speed reducer. The members constituting the motor section 20 and the gear section 21 are housed in a common housing case, and these are unitized as a whole.

[0021] The mounting arms 3a to 3c for the motor unit are parts for disposing the motor unit 2 below the rear floor section 4r so as to be located on the vehicle rear side of the step section 43 of the floor section 4. The mounting arms 3a and 3b are parts directly related to the mounting structure of the motor unit 2 intended by the present invention, but the mounting arm 3c is not. The base end portion of this mounting arm 3c is attached to the substantially central portion in the vehicle width direction of the motor unit 2 using a bolt 85 or the like and protrudes toward the vehicle rear side (including obliquely upward to the vehicle rear). Although illustration and description are omitted, the tip end portion of this mounting arm 3c is connected to a high-strength portion provided on the lower surface side of the rear floor section 4r.

[0022] The base ends of the mounting arms 3a and 3b for the motor unit are attached to the left and right sides of the motor unit 2 via bolts 81a and 81b, and project toward the front side of the vehicle (including the diagonally upward front of the vehicle). A rubber bush 30 is fixed to the tip ends of these mounting arms 3a and 3b, and as will be described later, this rubber bush 30 is supported by a bracket 6 for the motor unit.

[0023] The motor unit 2 is asymmetric left and right. In contrast, the pair of reinforcing members 5 and the pair of brackets 6 for mounting the motor unit shown in FIG. 1 are symmetric left and right. For this reason, for convenience of explanation, the configuration on the side corresponding to the mounting arm 3a will be mainly described.

[0024] As well shown in FIGS. 4 and 5, the reinforcing member 5 for mounting the motor unit is, for example, a structure in which first to third members 51 to 53 are joined in series. The first member 51 has a flange portion 51a whose outer peripheral edge is loop-shaped in bottom view, and a central region surrounded by this flange portion 51a is a downwardly bulging portion 51b. The flange portion 51a of this first member 51 is joined to the lower surface portion of the rear floor portion 4r. However, as shown in a partially enlarged view of FIG. 3, a part of the flange portion 51a (portion denoted by reference numeral n1) is interposed between the upper flange portion 10a of the rear side member 10 and the rear floor panel 41, etc., and is overlapped on the rear side member 10, and welding with the rear side member 10 is achieved. Note that the configuration for joining the first member 51 to the rear side member 10 is not limited to this. For example, a part of the first member 51 may be overlapped and joined to the lower surface side of the upper flange portion 10a of the rear side member 10, or it may be configured to be overlapped and joined to the side surface portion of the main body portion of the rear side member 10.

[0025] The second member 52 of the reinforcing member 5 has a substantially flat cross-sectional hat shape for each part, and is configured such that a pair of flange portions 52b are continuously provided at both side edges of the main plate portion 52a (see Fig. 6). This second member 52 can be divided into a substantially horizontal upper portion and a lower portion, and an upright intermediate portion connecting these upper and lower portions. Similar to the second member 52, the third member 53 has a substantially flat cross-sectional hat shape for each part, and is configured such that a pair of flange portions 53b are continuously provided at both sides of the main plate portion 53a. This third member 53 is joined to the second member 52 so as to protrude forward from the lower portion of the second member 52.

[0026] The region near the front end of the third member 53 is overlapped and joined to the rear wall portion 11a of the floor cross member 11. On the other hand, in addition to being joined to the third member 53, the lower portion of the second member 52 is overlapped and joined to the lower surface portion of the floor cross member 11. The intermediate portion of the second member 52 is overlapped and joined to the rear wall portion 43a of the step portion 43, and the upper portion of the second member 52 is overlapped and joined to the lower surface portion of the first member 51. From the above, the reinforcing member 5 (the first to third members 51 to 53) is configured to bridge-connect the floor cross member 11 and the rear side member 10 in a form along the step portion 43.

[0027] As shown in Fig. 7, the bracket 6 for the motor unit is configured such that an upper plate portion 60, an intermediate plate portion 61, and a lower plate portion 62 are connected vertically, and a pair of left and right support piece portions 63 project from both left and right side edges of the intermediate plate portion 61 toward the rear side of the vehicle. As shown well in FIGS. 4 and 5, this bracket 6 is overlapped and joined to the lower surface side and the rear surface side of the reinforcing member 5. The upper plate portion 60 is connected to the first member 51 of the reinforcing member 5 using bolts 82a (such connection is included in the joining as referred to in the present invention, similar to welding). The intermediate plate portion 61 is overlapped on the second member 52 and connected using bolts 82b and 82c. A part of the lower plate portion 62 is a front extending portion 62a extending to the vehicle front side from the lower front end portion of the reinforcing member 5 (the front end portion of the third member 53). This front extending portion 62a is overlapped on the lower surface portion of the floor cross member 11 and connected using bolt 82d.

[0028] The rubber bush 30 of the mounting arm 3a for the motor unit is interposed between a pair of support piece portions 63 of the bracket 6 and is mounted using bolts and nuts 83a and 83b. The mounting structure of the other mounting arm 3b is the same as the mounting structure of the mounting arm 3a.

[0029] Next, the operation of the vehicle structure A described above will be explained.

[0030] First, as a means for increasing the mounting strength of the motor unit 2, this vehicle structure A includes a pair of left and right reinforcing members 5 for mounting the motor unit. Here, each reinforcing member 5 is configured to bridge-connect the floor cross member 11 and the rear side member 10 as vehicle body skeleton members using the first to third members 51 to 53 along the step portion 43. Therefore, the portion where the reinforcing member 5 is provided can be made into a portion with quite high strength.

[0031] Further, a bracket 6 for the motor unit is joined (connected) to the reinforcing member 5. Here, in addition to being overlapped and joined to the lower surface side and the rear surface side of the reinforcing member 5, this bracket 6 has a front extending portion 62a extending to the vehicle front side from the reinforcing member 5, and this front extending portion 62a is joined to the lower surface portion of the floor cross member 11. According to such a configuration, the synergistic effect by the combination of both the reinforcing member 5 and the bracket 6 The strength enhancement effect will be quite high.

[0032] The motor unit 2 is attached to the stepped portion 43 of the floor portion 4, at the portion where the above-described reinforcing member 5 and the bracket 6 are combined to enhance the strength, so that the mounting property of the motor unit 2 during vehicle travel can be improved. In addition, when a rear-end collision of the vehicle occurs and a collision load F acts on the motor unit 2 from the rear side of the vehicle as shown in FIG. 2, the reinforcing member 5 and the bracket 6 receive the collision load F at the provided location, and it is possible to suppress the motor unit 2 from being largely displaced toward the front side of the vehicle. Therefore, it is possible to avoid the motor unit 2 from strongly colliding with the battery 98.

[0033] The reinforcing member 5 and the bracket 6 do not protrude so much, and it is possible to form them in a relatively small size. As a result, an increase in vehicle weight and manufacturing cost can also be suppressed.

[0034] The present invention is not limited to the content of the above-described embodiment. The specific configuration of each part of the vehicle structure according to the present invention can be variously designed and changed within the scope intended by the present invention.

[0035] In the above-described embodiment, the reinforcing member 5, which is the mounting target portion of the motor unit, is configured by using three members (first to third members 51 to 53) joined to each other, but the present invention is not limited thereto. The specific number and shape of the members constituting the reinforcing member are not limited. It is also possible to configure it as a single member. In the above-described embodiment, the bracket 6 for the motor unit is configured by using a single member, but it is not limited to this, and it is also possible to configure it by combining a plurality of members. The main requirement for this bracket is that it has a front extension portion that is overlapped and joined to the lower surface side and the rear surface side of the reinforcing member and extends to the front side of the vehicle with respect to the reinforcing member and is joined to the lower surface portion of the floor cross member. Further, the joining means of the bracket to the reinforcing member is not limited to bolt fastening, and other means such as welding can be adopted, for example.

[0036] In the above-described embodiment, the attachment structure of the attachment arms 3a and 3b for the motor unit applies the attachment structure intended by the present invention, but the present invention is not limited to this. In the present invention, when a plurality of attachment arms for the motor unit are provided, if the attachment structure intended by the present invention is applied to at least one of them, it is included in the technical scope of the present invention. The specific type of vehicle to which the present invention is applied (such as a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHV), an electric vehicle (EV), etc.) is not limited. The specific configuration of the motor unit is also not limited.

Explanation of Reference Numerals

[0037] A Vehicle Structure 10 Rear Side Member 11 Floor Cross Member 2 Motor Unit 4 Floor Portion 4f Front Floor Portion 4r Rear Floor Portion 42a Rear Wall Portion (of the step portion) 43 Step Portion (of the floor portion) 5 Reinforcing Member 6 Bracket (for motor unit) 62a Front Extension Portion

Claims

1. A vehicle structure provided in a region closer to the center or rear in the vehicle longitudinal direction of the floor portion of the vehicle, and having a step portion that divides the floor portion into a rear floor portion and a front floor portion having a lower height than the rear floor portion, A motor unit for driving a drive shaft disposed below the rear floor portion so as to be located on the rear side of the vehicle of this step portion, A rear side member located on the outer side in the vehicle width direction of this motor unit and extending in the vehicle longitudinal direction on the lower surface side of the rear floor portion, A vehicle structure comprising: A floor cross member joined to at least one of the lower surface sides of the step portion or the front floor portion and extending in the vehicle width direction, A reinforcing member in which a plurality of portions respectively joined to the floor cross member, the rear wall portion of the step portion, and the rear side member are connected in series, Further comprising: The vehicle structure, wherein the reinforcing member is a portion to which the motor unit is attached.

2. A vehicle structure provided in a region closer to the center or rear in the vehicle longitudinal direction of the floor portion of the vehicle, and having a step portion that divides the floor portion into a rear floor portion and a front floor portion having a lower height than the rear floor portion, A motor unit for driving a drive shaft disposed below the rear floor portion so as to be located on the rear side of the vehicle of this step portion, A vehicle structure comprising: A floor cross member joined to at least one of the lower surface sides of the step portion or the front floor portion and extending in the vehicle width direction, A reinforcing member in which a plurality of portions respectively joined to the rear wall portion of the floor cross member, the rear wall portion of the step portion, and the lower surface portion of the rear floor portion are connected in series, A bracket for the motor unit that enables attachment of the motor unit to this reinforcing member, Further comprising: The bracket for the motor unit is overlapped and joined to the lower surface side and the rear surface side of the reinforcing member, and has a front extension portion that extends to the front side of the vehicle with respect to the reinforcing member and is joined to the lower surface portion of the floor cross member. A vehicle structure characterized by this.

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