JP7006340B2 - Support structure and front structure of high voltage unit for vehicle - Google Patents

Description

This specification discloses a support structure of a high voltage unit and a vehicle front structure including the support structure.

For example, as described in Patent Document 1, a power unit chamber (also referred to as a motor compartment) in which a rotary electric machine as a drive source is mounted is provided in the front portion of an electric vehicle.

In the power unit room, the rotary electric machine is supported by the skeleton member of the vehicle. For example, in the MG compartment, a pair of front side members are extended as skeletal members along the front-rear direction of the vehicle. Further, a motor compartment cross member (hereinafter, appropriately referred to as MC cross member) is provided so as to be hung on the pair of front side members in the vehicle width direction. A rotary electric machine (drive device) is mounted on the MC cross member.

As illustrated in FIG. 10, the MC cross member 120 has a substantially square shape, and an opening 121 is formed in the center. For example, a rotary electric machine 122 is attached below the MC cross member 120. Further, above the MC cross member 120, a power control unit 124 (hereinafter, appropriately referred to as PCU) for performing power conversion, a charger 126, and the like are mounted. A high voltage cable (not shown) connecting the PCU 104 and the rotary electric machine 122 is arranged in the opening 121 of the MC cross member 120. The rotary electric machine 122, PCU 104, charger 126 and the like are assembled to the MC cross member 120 to form a high voltage unit, and the unit is fastened to the front side members 112A and 112B via the MC cross member 120.

Japanese Unexamined Patent Publication No. 2004-314803

By the way, at the time of a frontal collision of a vehicle, particularly at the time of a full-wrap collision in which a substantially front width of the entire surface of the vehicle collides with a colliding body, an impact load may be applied to the MC cross member to cause deformation. For example, the opening of the MC cross member is crushed and deformed with the input of an impact load. The crushing of the opening may put pressure on the high-voltage cable arranged (arranged) in the opening. In addition, there is a demand to improve the rigidity of the MC cross member in order to protect the high-voltage components mounted on it. Therefore, this specification discloses a support structure of a high voltage unit and a vehicle front structure capable of suppressing deformation of the MC cross member as compared with the conventional case.

The vehicle front structures disclosed herein are spaced apart in the vehicle width direction and are crossed between a pair of front side members, each extending in the vehicle front-rear direction, and the pair of front side members. A cross member including a front cross portion extending in the vehicle width direction, a rear cross portion provided behind the front cross portion and extending in the vehicle width direction, and a high-voltage component. A mount that is connected to the cross member and includes a mount that is hung between the front cross portion and the rear cross portion, and an opening that penetrates in the vertical direction is formed in the center of the cross member. The front and rear ends of the mount are characterized in that the opening of the cross member is straddled in the front-rear direction of the vehicle and fastened to the cross member .

With such a configuration, since the mount is hung between the front cross portion and the rear cross portion, deformation in the direction approaching the rear cross portion of the front cross portion is effectively prevented. As a result, it is possible to suppress the deformation of the MC cross member as compared with the conventional case.

The other vehicle front structures disclosed herein are spaced apart in the vehicle width direction and spanned between a pair of front side members, each extending in the vehicle front-rear direction, and the pair of front side members. A cross member including a front cross portion extending in the vehicle width direction, a rear cross portion provided behind the front cross portion and extending in the vehicle width direction, and a high-voltage component. A mount that is connected to the cross member, and is attached to the mount that is hung between the front cross portion and the rear cross portion and the outer surface of each front side member in the vehicle width direction, and is more vehicle than the front side member. The cross member and the front side member are provided with a gusset that protrudes outward in the width direction and whose dimension in the vehicle width direction becomes smaller as the vehicle moves backward, and the cross member and the front side member are at the same vehicle front-rear position as the rear end of the gusset. At a position in the vehicle front-rear direction that faces the vehicle in a state of being separated in the width direction and is the same as the rear end of the gusset or behind the rear end of the gusset, one or more on the outer surface of the cross member in the vehicle width direction. An overhanging wall is provided, and the overhanging wall is characterized in that it overhangs outward in the vehicle width direction from the front of the overhanging wall.
The cross member includes an upper member forming the upper surface of the cross member and a lower member forming the bottom surface of the cross member, and the upper member and the lower member are closed by being connected to each other. A cross section is formed, and the mount, the upper member, and the lower member may be jointly fastened with a bolt penetrating the closed cross section and a nut screwed to the bolt.

In this case, the bolt penetrates the closed cross section, so that the mounting rigidity of the bolt and the torsional rigidity of the cross member are improved.

Further, the mount includes a base portion fastened to the bottom surface or the upper surface of the front cross portion and the rear cross portion, and a protruding portion protruding from the center of the base portion in the vehicle height direction, and the base. When the portions are fastened to the front cross portion and the rear cross portion, the protruding portion may be located in the gap between the front cross portion and the rear cross portion.

With such a configuration, even if the front cross portion tries to be deformed to the rear of the vehicle, it comes into contact with the protruding portion, so that the deformation of the front cross portion and the deformation of the cross member are effectively prevented.

Here, among the front side members, the same vehicle front-rear direction position as the rear end of the gusset is a place where stress tends to concentrate and the front side member tends to bend at the time of a minute lap collision or an oblique collision. At a position where the front side member is likely to bend, the cross member and the front side member face each other in a state of being separated from each other in the vehicle width direction, so that the front side member can be reliably bent. Then, by bending the front side member, the collision load can be transmitted from this front side member to the opposite front side member via the cross member. That is, the collision load at the time of a minute lap collision or an oblique collision can be transmitted to the front side member on the opposite side without going through the power unit.

With such a configuration, the backward movement of the bent front side member is restricted by the overhanging wall. As a result, the collision load is less likely to escape to the rear of the vehicle, so that the collision load can be more reliably transmitted from the front side member to the cross member.

Further, the end face of the front side member in the vehicle width direction is provided with a reinforcing bead extending in the front-rear direction of the vehicle, which is temporarily interrupted in the middle, and the overhanging wall is interrupted by the reinforcing bead. It may be provided at the same position as the location, or at a position in the vehicle front-rear direction behind the interrupted portion of the reinforcing bead.

The break point of the reinforcing bead is also a place where stress is likely to be concentrated and a place where the front side member is easily bent at the time of a minute lap collision or an oblique collision. By providing the overhanging wall at the same position where the front side member is easily bent or at a position in the vehicle front-rear direction behind the position where the front side member is easily bent, the rear movement of the front side member is more reliably suppressed and the front is fronted. The collision load can be transmitted more reliably from the side member to the cross member.

Further, the cross member may have a height direction dimension at the end portion in the vehicle width direction larger than the height direction dimension at the center in the vehicle width direction.

With such a configuration, the area of the end face of the cross member in the vehicle width direction tends to be large, and when the front side member is bent, the front side member and the cross member come into contact with each other more reliably.

Further, a bracket for connecting the cross member and the front side member may be provided with the cross member and the front side member separated from each other in the vehicle width direction.

By using such a bracket, a space where the front side member can bend can be easily secured between the cross member and the front side member.

In this case, the cross member includes an upper member forming the upper surface of the cross member and a lower member forming the bottom surface of the cross member, and the upper member and the lower member are connected to each other. The bracket, the upper member, and the lower member are fastened together with a first fastening bolt penetrating the closed cross section and a nut screwed into the first fastening bolt. You may.

By penetrating the closed cross section of the first fastening bolt, the mounting rigidity of the first fastening bolt and the torsional rigidity of the cross member are improved.

Further, the bracket is fastened to the cross member and the front side member at a position in the vehicle front-rear direction rearward from the rear end of the gusset, and the bracket is used for fastening to the cross member and is used for the vehicle. It has a plurality of first fastening holes arranged in the front-rear direction, and a load-bearing portion, which is a predetermined gap, is interposed between each first fastening hole and the inner end portion of the bracket in the vehicle width direction. The load-bearing portion located in front may have higher strength than other load-bearing portions.

With such a configuration, the bracket can easily rotate following the bending of the front side member.

Further, the cross member may further include a pair of side portions for connecting the ends of the front cross portion and the rear cross portion.

With such a configuration, the area of the end face of the cross member in the vehicle width direction tends to be large, and when the front side member is bent, the front side member and the cross member come into contact with each other more reliably.

The support structure of the high voltage unit for a vehicle disclosed in the present specification is a pair of mounts assembled at both ends in the width direction of the rotary electric machine unit and a pair of front side members extending in the front-rear direction of the vehicle. A support structure for a high-voltage unit for a vehicle, comprising a cross member, which is fastened at both ends in a direction and has a cross member to which the rotary electric machine unit is assembled below via the pair of mounts and a high-voltage device is assembled above. An opening that penetrates in the vertical direction is formed in the center of the cross member, and the front and rear ends of the pair of mounts straddle the opening of the cross member in the front and rear direction of the vehicle to form the cross member. To be concluded.

With this configuration, the front and rear ends of the pair of motor mounts are fastened to the MC cross member across the opening of the MC cross member in the front-rear direction of the vehicle. Therefore, when a collision load is applied to the MC cross member at the time of a frontal collision of the vehicle, a compressive load is applied to the pair of motor mounts via the fastening portion with the MC cross member. Compressive stress is generated in the motor mount to withstand this compressive load. By stretching the motor mount against the compressive load in this way, the crushing of the opening of the MC cross member is suppressed.
The other vehicle front structures disclosed herein are spaced apart in the vehicle width direction and spanned between a pair of front side members, each extending in the vehicle front-rear direction, and the pair of front side members. A cross member including a front cross portion extending in the vehicle width direction, a rear cross portion provided behind the front cross portion and extending in the vehicle width direction, and a high-voltage component. A mount that is connected to the cross member, and is attached to the mount that is hung between the front cross portion and the rear cross portion and the outer surface of each front side member in the vehicle width direction, and is more vehicle than the front side member. The cross member and the front side are in a state where the cross member and the front side member are separated from each other in the width direction of the gusset, which protrudes outward in the width direction and whose dimension in the vehicle width direction becomes smaller as the vehicle moves backward. A bracket for connecting the members is provided, and the cross member and the front side member face each other in the same vehicle front-rear direction position as the rear end of the gusset, with the cross member and the front side member facing each other in a state of being separated from each other in the vehicle width direction. , A plurality of brackets are fastened to the cross member and the front side member at a position in the vehicle front-rear direction rearward from the rear end of the gusset, and the brackets are used for fastening to the cross member and are arranged in the vehicle front-rear direction. The first fastening hole of the above is provided, and a load-bearing portion, which is a predetermined gap, is interposed between each first fastening hole and the inner end portion of the bracket in the vehicle width direction. The load section is characterized in that it has a higher strength than other load-bearing sections.

According to the vehicle front structure and the support structure of the high voltage component for the vehicle disclosed in the present specification, the deformation of the MC cross member can be suppressed as compared with the conventional case.

It is an exploded perspective view which exemplifies each apparatus and member constituting the vehicle high voltage unit which concerns on this embodiment. It is a perspective view explaining the structure of a rotary electric machine unit and a motor mount. It is a perspective view which illustrates the assembly process (1/6) of the high voltage unit for a vehicle. It is a perspective view which illustrates the assembly process (2/6) of the high voltage unit for a vehicle. It is a perspective view which illustrates the assembly process (3/6) of the high voltage unit for a vehicle. It is a perspective view which illustrates the assembly process (4/6) of the high voltage unit for a vehicle. It is a perspective view which illustrates the assembly process (5/6) of the high voltage unit for a vehicle. It is a perspective view which illustrates the assembly process (6/6) of the high voltage unit for a vehicle. It is a top view explaining the behavior of MC cross member and a motor mount at the time of a forward collision. It is an exploded perspective view which illustrates each member constituting the high voltage unit for a vehicle which concerns on a prior art. It is a schematic diagram which shows the vehicle front structure. It is an exploded perspective view around the MC cross member. It is a figure which shows the appearance of the microlap collision or the oblique collision. It is a top view of the MC cross member. It is an exploded perspective view of the MC cross member. It is an end view of FIG. 4 taken along the line AA. It is a perspective view around the front end of the front side member. It is an exploded perspective view of a support bracket. It is a perspective view which shows the state of attachment of the support bracket. It is a schematic end view of the cutting line passing through the first fastening bolt. It is a perspective view of a rotary electric machine unit and a motor mount. It is schematic cross-sectional view which shows the state which the member side fastening part of the left side motor mount was fastened to MC cross member.

FIG. 1 illustrates devices and members constituting the vehicle high voltage unit 9. In FIGS. 1 to 9, the vehicle front-rear direction is indicated by the axis represented by the symbol Fr, the vehicle width direction is indicated by the axis represented by the symbol Rw, and the vertical direction is indicated by the axis represented by the symbol Up. The symbol Fr is an abbreviation for Front, and the front-rear axis Fr has the forward direction of the vehicle as the positive direction. The symbol Rw is an abbreviation for Right Left, and the width direction axis Rw has the right width direction as the positive direction. Further, the height axis Up has an upward direction as a positive direction. Further, the left and right in the following description mean the left and right as seen from the occupants of the vehicle, unless otherwise specified.

As shown in FIG. 1, these Fr axis, Rw axis, and Up axis are orthogonal to each other. In the following description, these three axes will be used as a reference as appropriate. For example, the "front end" refers to the end of any member on the positive direction of the FR axis, and the "rear end" refers to the end of any member on the negative direction of the Fr axis. "Inside in the width direction" refers to the inside in the width direction of the vehicle relative to the Rw axis, and "outside in the width direction" refers to the outside in the width direction of the vehicle relative to the Rw axis. Further, "upper side" relatively refers to the positive direction side of the Up axis, and "lower side" relatively refers to the negative direction side of the Up axis.

The vehicle high voltage unit 9 includes a rotary electric machine unit 22, a PCU 24, and a charger 26. Further, as a support structure thereof, an MC cross member 20 and a pair of motor mounts 28A and 28B are provided. For example, the high voltage unit 9 for a vehicle is mounted in a power unit chamber provided in the front portion of an electric vehicle.

In the power unit room, a pair of front side members 12A and 12B are extended in the front-rear direction of the vehicle. The vehicle high voltage unit 9 is assembled to the pair of front side members 12A and 12B. For example, as will be described later, both ends of the MC cross member 20 in the width direction are fastened to the front side members 12A and 12B via the support brackets 32A and 32B.

The rotary electric machine unit 22 includes a rotary electric machine MG and a transmission TA (transaxle) which are drive sources of a vehicle. In the example shown in FIG. 1, the rotary electric machine unit 22 is arranged horizontally, and is arranged in the power unit chamber so that the longitudinal direction of the rotary electric machine unit 22 faces the vehicle width direction.

Referring to FIG. 2, a plurality of fastening holes are provided at both ends of the rotary electric machine unit 22 in the width direction. Specifically, fastening holes 23A to 23E are formed at the widthwise end portion and the upper surface of the rotary electric machine MG. Fastening holes 23F to 23I are formed at the widthwise end and the upper surface of the transmission TA. As will be described later, the motor mounts 28A and 28B are fastened to the rotary electric machine unit 22 by aligning and bolting the fastening holes 23A to 23I and the fastening holes 53A to 53I of the motor mounts 28A and 28B.

Returning to FIG. 1, the PCU 24 is a power converter provided in an electric circuit connecting a rotary electric machine MG and a battery (not shown). The PCU 24 includes a power conversion circuit such as a DC / DC converter or an inverter. Further, with reference to FIG. 6, fastening holes 83B to 83E are formed in the leg portions 24A extending downward from the front end portion of the PCU 24 via an insulating member or the like. Similarly, fastening holes 83N to 83Q are formed in the leg portions 24B extending downward from the rear end portion of the PCU 24 via an insulating member or the like.

The charger 26 is connected to a battery (not shown) and includes a booster circuit for power conversion, a transformer circuit for cutting off a DC component, and the like. Further, fastening holes 83F and 83H are formed in the leg portions 26A extending downward from the front end portion of the charger 26 via an insulating member or the like. Similarly, fastening holes 83K and 83M are formed in the leg portions 26B extending downward from the rear end portion of the charger 26 via an insulating member or the like.

The MC cross member 20 is a support member for the vehicle high voltage unit 9. The MC cross member 20 is arranged in the power unit chamber so that the longitudinal direction is directed to the vehicle width direction as shown in FIG. The MC cross member 20 has a substantially square shape, and an opening 34 penetrating in the vertical direction is formed in the center thereof. From another point of view, the MC cross member 20 includes a front cross portion 20F extending in the vehicle width direction, a rear cross portion 20R extending in the vehicle width direction behind the front cross portion 20F, a front cross portion 20F, and a rear cross. It can be said that the portion 20R has a pair of side portions 20S connecting both ends in the width direction. The portion surrounded by the front cross portion 20F, the rear cross portion 20R, and the pair of side portions 20S is the opening 34. As illustrated in FIG. 7, a high voltage cable 19 connecting the PCU 24 and the rotary electric machine MG is arranged in the opening 34. The skeleton member surrounding the opening 34 has, for example, a closed cross-sectional structure.

As shown in FIG. 1, a high voltage device such as a PCU 24 and a charger 26 is assembled above the MC cross member 20. Further, a rotary electric machine unit 22 is assembled below the MC cross member 20. As will be described later, the rotary electric machine unit 22 is assembled to the MC cross member 20 via the motor mounts 28A and 28B.

As shown in FIG. 4, the MC cross member 20 is provided with a plurality of fastening holes 21A to 21V. By aligning the plurality of fastening holes with the fastening holes and stud bolts provided on the chargers 26, PCU24, and motor mounts 28A and 28B and bolting them together, the charger 26 is attached to the MC cross member 20. , PCU 24, and rotary electric machine unit 22 are assembled.

Referring to FIG. 2, the motor mount 28A includes an MG-side fastening portion 52A to be fastened to the rotary electric machine unit 22 and a member-side fastening portion 54A to be fastened to the MC cross member 20. The MG side fastening portion 52A is extended along the front-rear direction, and a plurality of fastening holes 53F to 53I are formed along the extending direction. The member-side fastening portion 54A is also extended along the front-rear direction in the same manner as the MG-side fastening portion 52A. Further, fastening holes 83G and 83L are provided along the extending direction. As will be described later, the fastening holes 83G and 83L at both front and rear ends of the member side fastening portion 54A straddle the opening 34 of the MC cross member 20 in the front-rear direction and are aligned with the fastening holes 21G and 21L of the MC cross member 20. Be fastened. In other words, the member-side fastening portion 54A (motor mount 28A) is hung between the front side cross portion 20F and the rear side cross portion 20R.

The motor mount 28B includes an MG-side fastening portion 52B to be fastened to the rotary electric machine unit 22, and a member-side fastening portion 54B to be fastened to the MC cross member 20. The MG side fastening portion 52B is extended along the front-rear direction, and a plurality of fastening holes 53A to 53E are formed along the extending direction. The member-side fastening portion 54B is also extended along the front-rear direction in the same manner as the MG-side fastening portion 52B. Further, stud bolts 86A, 86S and fastening holes 83R, 83T are provided along the extending direction. As will be described later, the stud bolts 86A, 86S and the fastening holes 83R, 83T at both front and rear ends of the member side fastening portion 54B straddle the opening 34 of the MC cross member 20 in the front-rear direction, and the fastening holes 21A of the MC cross member 20. Aligned with 21S, 21R, 21T and bolted. In other words, the member side fastening portion 54B (motor mount 28B) is hung between the front side cross portion 20F and the rear side cross portion 20R.

<Assembly process of high voltage unit for vehicle>
3 to 8 illustrate the assembly process of the vehicle high voltage unit 9 according to the present embodiment. As illustrated in FIG. 3, the motor mount 28A is arranged at one end in the width direction of the rotary electric machine unit 22, and the motor mount 28B is arranged at the other end. The fastening holes 53F to 53I of the motor mount 28A are aligned with the fastening holes 23F to 23I provided above the transmission TA of the rotary electric machine unit 22 and at the end in the width direction, and the bolts 92 are inserted into the fastening holes 23 and 53. Is screwed in. As a result, the motor mount 28A is fastened to the rotary electric machine unit 22.

Similarly, the fastening holes 53A to 53E of the motor mount 28B are aligned with the fastening holes 23A to 23E provided above the rotary electric machine MG of the rotary electric machine unit 22 and at the end in the width direction, and both fastening holes 23, The bolt 92 is screwed into 53. As a result, the motor mount 28B is fastened to the rotary electric machine unit 22.

Next, as illustrated in FIG. 4, the rotary electric machine unit 22 is assembled to the MC cross member 20 via the motor mounts 28A and 28B. First, the fastening holes 83G and 83L formed at both front and rear ends of the member-side fastening portion 54A of the motor mount 28A are aligned with the fastening holes 21G and 21L of the MC cross member 20, and bolts 92 are inserted into both fastening holes 21 and 83. It is screwed in and its tip is fastened with a nut 88.

Similarly, the stud bolts 86A and 86S formed at both front and rear ends of the member side fastening portion 54B of the motor mount 28B are inserted into the fastening holes 21A and 21S of the MC cross member 20, and the tips thereof are fastened with nuts 88. As a result, the fastening holes 83R and 83T of the member-side fastening portion 54B and the fastening holes 21R and 21T of the MC cross member 20 are aligned. The bolt 92 is screwed into both fastening holes 21 and 83.

FIG. 5 illustrates a plan view of an assembly including a rotary electric machine unit 22, an MC cross member 20, and motor mounts 28A and 28B. The front end portion (Fr axis positive direction end portion) of the MC cross member 20 projects forward from the front end portion of the rotary electric machine unit 22, and in the event of a forward collision, a collision load is applied to the MC cross member 20 before the rotary electric machine unit 22. It has a structure that can be added.

Further, the member-side fastening portions 54A and 54B of the motor mounts 28A and 28B are fastened to the MC cross member 20 across the opening 34 of the MC cross member 20 in the front-rear direction. In other words, the member-side fastening portions 54A and 54B of the motor mounts 28A and 28B are hung between the front cross portion 20F and the rear cross portion 20R. By providing such a structure, the motor mounts 28A and 28B function as reinforcing members of the MC cross member 20. That is, the compression stress is generated (tensioned) in the motor mounts 28A and 28B at the time of a forward collision, so that the crushing of the opening 34 of the MC cross member 20 is suppressed.

6 and 7 illustrate the process of assembling the PCU 24 and the charger 26 to the MC cross member 20. The fastening holes 83B to 83E and 83N to 83Q of the legs 24A and 24B of the PCU 24 are aligned with the fastening holes 21B to 21E and 21N to 21Q of the MC cross member 20. Further, bolts (not shown) are inserted into both fastening holes 21 and 83. As a result, the PCU 24 is fastened to the MC cross member 20. At the time of this fastening, a high voltage cable 19 (see FIG. 7) is arranged in the opening 34 of the MC cross member 20, and the PCU 24 and the rotary electric machine MG are electrically connected.

Further, the fastening holes 83F, 83H, 83K, 83M of the legs 26A, 26B of the charger 26 are aligned with the fastening holes 21F, 21H, 21K, 21M of the MC cross member 20. Further, bolts (not shown) are inserted into both fastening holes 21 and 83. As a result, the charger 26 is fastened to the MC cross member 20.

A rotary electric machine unit 22, a PCU 24, and a charger 26 are assembled to the MC cross member 20, and a vehicle high voltage unit 9 is configured. As shown in FIG. 7, the front end portion (Fr axis positive side end portion) of the MC cross member 20 projects forward from the front end portions of the PCU 24 and the charger 26, and in the event of a forward collision, the rotary electric machine unit 22 The structure is such that a collision load is applied to the MC cross member 20 before the PCU 24 and the charger 26.

7 and 8 show an example of a process of fastening the vehicle high voltage unit 9 to the front side members 12A and 12B via the support brackets 32A and 32B. The support bracket 32A includes fastening holes 74A and 74C that are aligned with the fastening holes 15A and 15B of the front side member 12A and bolted, and fastening holes 21I and 21J of the MC cross member 20 that project inward in the vehicle width direction from the fastening holes 74A and 74C. It is provided with fastening holes 74B and 74D that are aligned and bolted.

Similarly, the support bracket 32B has fastening holes 74F and 74H that are aligned with the fastening holes 15C and 15D of the front side member 12B and bolted, and fastening holes of the MC cross member 20 that project inward in the vehicle width direction from the fastening holes 74F and 74H. It is provided with fastening holes 74G and 74E that are aligned with 21U and 21V and bolted.

At the time of assembly, the support brackets 32A and 32B are previously fastened to the front side members 12A and 12B. In this state, the vehicle high voltage unit 9 is lifted up from below and fastened to the support brackets 32A and 32B as shown in FIG. As a result, the vehicle high voltage unit 9 is fastened to the front side members 12A and 12B via the support brackets 32A and 32B.

<Behavior during a forward collision>
FIG. 9 illustrates a plan view of the vehicle high voltage unit 9. For convenience, the PCU 24 and the charger 26 are not shown. At the time of a frontal collision of the vehicle, a collision load F1 toward the rear of the vehicle is applied to the MC cross member 20. At this time, a compressive load is applied to the member-side fastening portion 54A of the motor mount 28A through the bolts screwed into the fastening holes 83G and 83L along the vehicle front-rear direction. Along with this, a compressive stress σ1 is generated in the member-side fastening portion 54A.

Similarly, when the collision load F1 is applied to the MC cross member 20, the member-side fastening portion 54B of the motor mount 28B is connected to the stud bolts 86A, 86S and the bolts screwed into the fastening holes 83R, 83T. A compressive load is applied along the front-rear direction of the vehicle. Along with this, a compressive stress σ1 is generated in the member-side fastening portion 54B.

The compressive stress generated from the motor mounts 28A and 28B acts to stretch against the collision load, and as a result, the deformation of the MC cross member 20 is suppressed. By fastening the motor mounts 28A and 28B in the front-rear direction across the opening 34 in this way, the rigidity of the MC cross member 20 in the front-rear direction is improved, and deformation at the time of a forward collision is suppressed. In addition, by improving the so-called torsional rigidity, vibration of the MC cross member 20 and generation of noise associated therewith in normal operation are suppressed.

Next, another support structure and a vehicle front structure having the other support structure will be described. FIG. 11 is a schematic plan view of the vehicle front structure 10. Further, FIG. 12 is an exploded perspective view around the MC cross member 20.

First, the overall configuration of the vehicle front structure 10 will be briefly described. The vehicle front structure 10 is incorporated in an electric vehicle (for example, an electric vehicle, a fuel cell vehicle, etc.) traveling by power generated by a rotary electric machine MG. A power unit room 11 in which a power unit is installed is provided at the front of the vehicle. The power unit generates running power of the vehicle, and in this example, the rotary electric machine unit 22 described later functions as a power unit.

A bumper reinforcement (hereinafter abbreviated as "bumper RF") 14 extending in the vehicle width direction is provided at the front end of the power unit chamber 11. The bumper RF14 is curved in a plan view so as to be convex in front of the vehicle. Front side members 12 are connected to both ends of the bumper RF 14 in the vehicle width direction via a crash box 16. The crash box 16 absorbs collision energy at the time of a vehicle collision by compressing and deforming in the front-rear direction of the vehicle. Therefore, the crash box 16 is usually in a form that is easily compressed and deformed in the front-rear direction of the vehicle, for example, a form in which a plurality of concave beads are formed on the outer peripheral surface.

A front side member 12 is connected to the rear of the crash box 16. The front side member 12 is a skeleton member extending in the front-rear direction of the vehicle. As shown in FIG. 11, the two front side members 12 are arranged substantially parallel to each other with a sufficient distance in the vehicle width direction. The front side member 12 is provided with a stress concentration portion where stress is concentrated when a load is applied to the side surface thereof, which will be described later.

A gusset 18 is attached to the outer surface of each front side member 12 in the vehicle width direction. The gusset 18 is a member having a substantially triangular shape in a plan view, in which the dimension in the vehicle width direction becomes smaller as the vehicle advances to the rear of the vehicle. The front end of the gusset 18 is substantially the same as the front end of the front side member 12. The gusset 18 projects outward from the front side member 12 in the vehicle width direction, and receives a load input from the front side member 12 from the outside in the vehicle width direction.

An MC cross member 20 is provided between the pair of front side members 12. The MC cross member 20 is connected to the front side member 12 via a support bracket as in the above example. In other words, the MC cross member 20 is laid between the pair of front side members 12. However, the MC cross member 20 is not in contact with the front side member 12, and both 12 and 20 face each other in a state of being separated in the vehicle width direction. In other words, there is a slight gap between the MC cross member 20 and the front side member 12. This is to allow the front side member 12 to bend, which will be described later.

As shown in FIG. 12, the charger 26 and the PCU 24 are placed and fastened on the upper surface of the MC cross member 20. Further, below the MC cross member 20, a rotary electric machine is provided via a left motor mount 28L and a right motor mount 28R (hereinafter, when the left and right are not distinguished, the subscripts L and R are omitted and referred to as "motor mount 28"). The unit 22 is suspended and held. Similar to the above example, the rotary electric machine unit 22 includes a rotary electric machine MG and a transmission (transaxle) TA as a drive source of the vehicle. A plurality of fastening holes 23 are provided on the upper surface of the rotary electric machine unit 22 and both end faces in the width direction. The motor mount 28 is fastened to the rotary electric machine unit 22 by aligning the fastening holes 23 and the fastening holes 53 of the motor mount 28 and bolting them together.

The motor mount 28 includes an MG-side fastening portion 52 to be fastened to the rotary electric machine unit 22, and a member-side fastening portion 54 to be fastened to the MC cross member 20. The fastening of the motor mount 28 to the rotary electric machine unit 22 and the MC cross member 20 will be described in detail later. The motor mount 28 and the MC cross member 20 form a support structure for supporting a vehicle high-voltage unit (rotary electric machine unit 22, PCU 24, charger 26).

The PCU 24 is fastened to the upper surface of the MC cross member 20 via fastening bolts (not shown) inserted into the plurality of fastening holes 25, as in the above example. Further, the charger 26 is also fastened to the upper surface of the MC cross member 20 via fastening bolts (not shown) inserted into the plurality of fastening holes 27, as in the above example.

A high-voltage cable (not shown) for transmitting and receiving electric power is arranged between the rotary electric machine unit 22, the PCU 24, the charger 26, and the battery (not shown). A part of this high voltage cable is passed through an opening 34 provided in the center of the MC cross member 20.

Next, a case where a vehicle having the vehicle front structure 10 collides in front will be briefly described. Frontal collisions include a full-wrap collision in which the entire width of the front surface of the vehicle body collides with the collision body, a minute lap collision in which the collision body collides only with the edge of the front surface of the vehicle body (for example, 25% outside the front surface of the vehicle body), and a high-speed collision. There is an oblique collision in which a colliding body collides diagonally from the front of the vehicle.

In the case of a full-wrap collision, the collision load is input to the pair of left and right crash boxes 16 via the bumper RF14. In response to this impact load, the crash box 16 is compressed and deformed, and a part of the impact load is absorbed. The load that cannot be absorbed by the crash box 16 is further transmitted to the pair of left and right front side members 12. The front side member 12 absorbs and disperses the load while bending and deforming as necessary. In this process, the bumper RF14 that has moved backward or another member that is interposed between the bumper RF14 and the MC cross member 20 reaches the front end of the MC cross member 20, and a load toward the vehicle rear is applied to the MC cross member 20 as well. May be done. In this example, a motor mount 28 that crosses the opening 34 in the front-rear direction of the vehicle is attached to the MC cross member 20 in order to prevent the MC cross member 20 from being deformed by this backward load. Will also be described later.

On the other hand, the case of a minute lap collision or an oblique collision will be described with reference to FIG. In this case, the colliding body collides with the vehicle outside the front side member 12 in the vehicle width direction. Therefore, the collision load in this case is applied directly to the gusset 18 via the bumper RF14 or without the bumper RF14. The impact load applied to the gusset 18 is transmitted to the outer surface of the front side member 12 via the gusset 18. Then, in response to this collision load, as shown in FIG. 13, the front side member 12 bends inward in the vicinity of the rear end of the gusset 18 and enters the inside in the vehicle width direction. As a result, the front side member 12 comes into contact with the side surface of the MC cross member 20, and the collision load is further transmitted to the MC cross member 20. The MC cross member 20 receives this collision load, moves in the vehicle width direction, and abuts on the front side member 12 on the opposite side (on the right side of the vehicle in the illustrated example).

That is, the collision load at the time of a minute lap collision or an oblique collision is sequentially transmitted to the gusset 18 on one side, the front side member 12 on one side, the MC cross member 20, and the front side member 12 on the opposite side. Then, in the process of this transmission, the collision load is absorbed and dispersed. Further, the collision load is finally transmitted to the front side member 12 on the opposite side, so that the entire vehicle body can easily move in the direction of escaping from the collision load, and deformation and damage of each part of the vehicle due to the collision load are reduced. can.

As is clear from the above explanation, in the full lap collision, the MC cross member 20 is required not to be deformed, and in the minute lap collision and the oblique collision, the collision load is efficiently transmitted from the front side member 12 to the MC cross member 20. Is required to be done. In this example, the structure of each part is set so as to satisfy such a request. Hereinafter, the configuration of each part will be described in more detail.

First, the configuration of the MC cross member 20 will be described with reference to FIGS. 14 to 16. FIG. 14 is a plan view of the MC cross member 20, and FIG. 15 is an exploded perspective view of the MC cross member 20. Further, FIG. 16 is an end view taken along the line AA of FIG.

As described above, the MC cross member 20 is a member that is hung between the pair of front side members 12, and is a member on which the PCU 24 and the charger 26 are mounted and suspends and holds the rotary electric machine unit 22. .. As shown in FIG. 14, the MC cross member 20 is a substantially rectangular shape that is long in the vehicle width direction in a plan view. A long opening 34 is formed in the center of the MC cross member 20 in the vehicle width direction, and the MC cross member 20 has a substantially square shape as a whole. A part of the high voltage cable connected to the rotary electric machine unit 22, the PCU 24, and the charger 26 is arranged in the opening 34.

As shown in FIG. 15, the MC cross member 20 is configured by combining one upper member 36 and two lower members 38F and 38R. The upper member 36 includes an upper surface having a large opening formed in the center and a peripheral surface that hangs downward from the peripheral edge of the upper surface, and the bottom surface is completely opened. The front lower member 38F and the rear lower member 38R are members attached to the lower side of the upper member 36, and some steps are formed in the front-rear direction of the vehicle. In the following, when the front side and the rear side are not distinguished, the subscripts F and R are omitted and simply referred to as "lower member 38".

As shown in FIG. 16, the front lower member 38F and the rear lower member 38R form a closed cross section with the upper member 36. That is, the front lower member 38F is close to or in contact with the upper member 36 on its uppermost surface and front end surface, but is sufficiently separated from the upper member 36 at other points. Similarly, the rear lower member 38R is close to or in contact with the upper member 36 on its uppermost surface and rear end surface, but is sufficiently separated from the upper member 36 at other points.

By forming the MC cross member 20 into a hollow shape composed of the upper member 36 and the lower member 38 in this way, the strength of the MC cross member 20 is significantly improved as compared with the case where the MC cross member 20 is composed of a single plate material. can. In particular, with such a configuration, compression deformation of the MC cross member 20 in the vehicle width direction is effectively prevented. That is, in the case of a minute lap collision or an oblique collision, the MC cross member 20 is unlikely to be compressed and deformed even if a collision load in the vehicle width direction is received from the front side member 12. As a result, the collision load can be reliably transmitted by the front side member 12 on the opposite side. Although the upper member 36 and the lower member 38 are shown in FIG. 15 as a simple shape without beads or recesses, a plurality of beads or recesses may be provided in these members 36 and 38. The strength of the MC cross member 20 can be further improved by appropriately providing beads and recesses.

From another point of view, the MC cross member 20 includes a front cross portion 20F extending in the vehicle width direction, a rear cross portion 20R extending in the vehicle width direction behind the front cross portion 20F, and left and right ends of the front cross portion 20F. It can be roughly divided into a pair of side portions 20S connecting the left and right ends of the rear cross portion 20R. In the event of a microlap collision or an oblique collision, the side portion 20S functions as an input portion and an output portion of the collision load. That is, the collision load is input to the side portion 20S on one side via the gusset 18 on one side and the front side member 12 on one side. The impact load input from the side portion 20S on one side is transmitted to the side portion 20S on the opposite side via the front cross portion 20F and the rear cross portion 20R, and further, the opposite side from the side portion 20S on the opposite side. Is output to the front side member 12 of. As described above, it is desirable that the area of the side surface 20S facing the front side member 12 (the outer surface of the side unit 20S in the vehicle width direction) as large as possible is as large as possible in the side unit 20S that functions as the load input unit and the output unit.

Therefore, in this example, as shown in FIG. 15, the height direction dimension (thickness) De of the MC cross member 20 at the vehicle width direction end portion is larger than the vehicle height direction dimension Dc at the vehicle width direction center. I am doing it. Then, in order to realize such a dimension, the lower end side 60 of the front end surface and the rear end surface of the MC cross member 20 is formed in an upwardly convex arch shape. As a result, the outer surface of the side portion 20S in the vehicle width direction becomes larger, and the bent front side member 12 can more reliably contact the side portion 20S.

In this example, two overhanging walls 62 are provided on the outer surface of the side portion 20S. The overhanging wall 62 is a portion that overhangs outward in the vehicle width direction with respect to the position in front of the overhanging wall 62. The overhanging wall 62 can be formed by providing a step or a concave portion recessed inward in the vehicle width direction on the side portion 20S. Such an overhanging wall 62 hooks the bent front side member 12 in the event of a minute lap collision or an oblique collision, and restricts the backward movement of the front side member 12.

That is, in the event of a minute lap collision or an oblique collision, not only the front side member 12 bends but also the front side member 12 moves to the rear of the vehicle. When the front side member 12 freely moves rearward, the collision load is less likely to be transmitted to the MC cross member 20. On the other hand, if the side portion 20S is provided with an overhanging wall 62 overhanging outward in the vehicle width direction, the bent front side member 12 abuts on the overhanging wall 62, whereby the overhanging of the front side member 12 is concerned. Movement to the rear of the exit wall 62 is restricted. As a result, the collision load at the time of a minute lap collision or an oblique collision can be more reliably transmitted to the MC cross member 20.

Here, at the time of a minute lap collision or an oblique collision, the front side member 12 tends to bend slightly behind the rear end or the rear end of the gusset 18. The overhanging wall 62 is provided at the same position in the front-rear direction of the vehicle as the place where the bending is likely to occur (the rear end of the gusset 18 or slightly behind the rear end), or slightly behind the place where the bending is likely to occur. Is desirable. By providing the overhanging wall 62 at such a position, the bent front side member 12 can be hooked more reliably.

However, the bending position of the front side member 12 is appropriately different depending on the direction and magnitude of the input collision load. For example, the bending position of the front side member 12 changes slightly between the time of a minute lap collision and the time of an oblique collision. Therefore, it is desirable that two or more overhanging walls 62 are provided on one side portion 20S so that the bending position of the front side member 12 may change.

By the way, in the case of a minute lap collision and an oblique collision, it is desirable that the front side member 12 bends inward in the vehicle width direction. However, when the front side member 12 and the MC cross member 20 are in contact with each other without a gap in the vehicle width direction, the bending of the front side member 12 is hindered by the MC cross member 20. Therefore, in this example, the MC cross member 20 and the front side member 12 are separated from each other in the vehicle width direction at the same vehicle front-rear direction position where the front side member 12 is expected to bend. As a result, a space for bending and deforming the front side member 12 can be secured, and the front side member 12 can be bent more reliably. The portion where bending is expected is the stress concentration portion of the MC cross member 20, the rear end of the gusset 18, or the interrupted portion 42 of the reinforcing bead 40 (see FIG. 17), which will be described in detail later.

Next, the front side member 12 and the gusset 18 will be described with reference to FIG. FIG. 17 is a perspective view of the front end of the front side member 12. The front side member 12 is a skeleton member extending in the front-rear direction of the vehicle, and is a hollow square pipe-shaped member. The front side member 12 is provided with some stress concentration portions where stress is easily concentrated and bending is easy. One of the stress concentration portions is near the rear end of the gusset 18. The load input through the gusset 18 tends to concentrate near the rear end of the gusset 18. The front side member 12 tends to bend inward in the vehicle width direction in the vicinity of the rear end of the gusset 18. Further, a reinforcing bead 40 is provided on the outer surface 12o of the front side member 12 in the vehicle width direction, and the interrupted portion 42 of the reinforcing bead 40 also functions as a stress concentration portion. That is, the reinforcing bead 40 is provided to improve the strength of the front side member 12, and is a linear bead that is long in the front-rear direction of the vehicle. However, the reinforcing beads 40 are not continuous in the front-rear direction of the vehicle, and are interrupted in the middle. At the location where the reinforcing bead 40 is formed, the front side member 12 is difficult to bend. On the other hand, the strength of the interrupted portion 42 of the reinforcing bead 40 is locally reduced, and stress tends to be concentrated. Therefore, the interrupted portion 42 of the reinforcing bead 40 is a stress concentration portion where stress is easily concentrated and the front side member 12 is easily bent.

In this example, the break portion 42 of the reinforcing bead 40 is provided behind the rear end of the gusset 18. Therefore, depending on the stress input form, the front side member 12 may bend at the break point 42 (rearward from the rear end of the gusset 18) of the reinforcing bead 40. Even in this case, the front side member 12 and the MC cross member 20 are separated from each other in the vehicle width direction at the same vehicle front-rear direction position as the interrupted portion 42 of the reinforcing bead 40 so that the front side member 12 can be reliably bent. There is. Further, at least one of the above-mentioned overhanging walls 62 is provided at the same position as the break point 42 of the reinforcing bead 40, or at a position in the vehicle front-rear direction behind the break point 42 of the reinforcing bead 40. The gusset 18 is attached to the outer surface 12o of the front side member 12 as shown by the alternate long and short dash line in FIG. Since the configuration of the gusset 18 can appropriately utilize the prior art, the detailed description thereof is omitted here.

The front side member 12 and the MC cross member 20 are connected to each other via a support bracket. FIG. 18 is an exploded perspective view of the support bracket. Further, FIG. 19 is a perspective view showing how the support bracket is attached. The support bracket has two bracket pieces 44, 46. The two bracket pieces 44, 46 are stacked one above the other to form a support bracket. As shown in FIGS. 1 and 13, this support bracket is attached to the rear of the vehicle from the stress concentration portion (rear end of the gusset 18 or the break point 42 of the reinforcing bead 40) where bending of the front side member 12 is expected. Be done. Further, this support bracket connects the front side member 12 and the MC cross member 20 with the front side member 12 and the MC cross member 20 separated from each other in the vehicle width direction.

The first bracket piece 44 connects the upper surface of the MC cross member 20 and the inner side surface 12i of the front side member 12 in the vehicle width direction. Therefore, the first bracket piece 44 has a substantially L-shape having a surface extending in a substantially horizontal direction along the upper surface of the MC cross member 20 and a surface extending in a substantially vertical direction along the inner side surface 12i of the front side member 12. It is in the shape of a figure. Three first fastening holes 64a to 64c are formed side by side in the front-rear direction on the horizontal surface of the first bracket piece 44. The first fastening holes 64a to 64c are holes through which the first fastening bolts 66a to 66c are inserted, and are provided at positions corresponding to the fastening holes 21a to 21c formed in the MC cross member 20. Further, on the vertical surface of the first bracket piece 44, two second fastening holes 70a (only one can be seen in FIGS. 18 and 19) are formed side by side in the front-rear direction. The second fastening hole 70a is a hole through which a second fastening bolt (not shown) is inserted, and is provided at a position corresponding to the fastening holes 13a and 13b formed on the inner side surface of the front side member 12.

The second bracket piece 46 connects the upper surface of the MC cross member 20 and the upper surface 12t of the front side member 12. Therefore, the second bracket piece 46 has a surface extending substantially horizontally along the upper surface of the MC cross member 20 and the upper surface 12t of the front side member 12. Further, the second bracket piece 46 also has an extension portion 46a that greatly extends outward so that it can be fastened to another member (for example, a suspension tower or the like).

Of the second bracket piece 46, one insertion hole 72 and two first fastening holes 74a and 74c are provided in the vicinity of the inner end portion in the vehicle width direction. The two first fastening holes 74a and 74c are arranged on both sides of the insertion hole 72 in the front-rear direction. The positions of the first fastening holes 74a and 74c and the insertion holes 72 are substantially the same as the positions of the first fastening holes 64a to 64c of the first bracket piece 44. However, the insertion hole 72 has a larger diameter than the heads of the first fastening bolts 66a to 66c.

Two third fastening holes 76a and 76b are formed side by side in the front-rear direction in the vicinity of the outer end portion of the second bracket piece 46 in the vehicle width direction. The third fastening holes 76a and 76b are provided at positions corresponding to the fastening holes 15a and 15b formed on the upper surface 12t of the front side member 12.

When connecting the MC cross member 20 and the front side member 12, first, the first bracket piece 44 is screwed and fastened to the inner side surface 12i of the front side member 12. Subsequently, the second bracket piece 46 is placed on the first bracket piece 44, and the second bracket piece 46 is screwed and fastened to the upper surface 12t of the front side member 12. After that, the MC cross member 20 to which the rotary electric machine unit 22, the PCU 24, and the charger 26 are assembled is lifted up, and the upper surface of the MC cross member 20 is arranged under the support bracket. In that state, the first and second bracket pieces 44 and 46 are screwed and fastened to the MC cross member 20 using the first fastening bolts 66a to 66c and the nuts 68a to 68c.

Here, of the three fastening holes 21a to 21c formed in the MC cross member 20, the front and rear fastening holes 21a and 21c are formed in both the upper member 36 and the lower member 38. The first fastening bolts 66a and 66c inserted into the fastening holes 21a and 21c penetrate the closed cross section of the MC cross member 20. This will be described with reference to FIG. FIG. 20 is a schematic end view of a cutting line passing through the first fastening bolt 66a.

As shown in FIG. 20, a collar 50 extending in the thickness direction is provided inside the MC cross member 20 (inside the closed cross section). The collar 50 is arranged coaxially with the fastening hole 21a formed in the upper member 36 and the lower member 38, and the height thereof is substantially the same as or slightly smaller than the height of the closed cross section. When fastening the MC cross member 20 to the first and second bracket pieces 44 and 46, the first fastening bolt 66a is used as the fastening hole 21a of the lower member 38, the collar 50, and the fastening hole 21a of the upper member 36. (1) It is inserted into the first fastening hole 64a of the bracket piece 44 and the first fastening hole 74a of the second bracket piece 46. Then, the nut 68a is screwed into the male screw protruding from the upper surface of the second bracket piece 46 and tightened. That is, the lower member 38, the collar 50, the upper member 36, the first bracket piece 44, and the second bracket piece 46 are connected to the first fastening bolt 66a and the nut 68a, and thus the first fastening bolts 66a and 66c are connected to the MC cross. By penetrating the closed cross section of the member 20, the mounting rigidity of the first fastening bolts 66a and 66c can be improved. Further, in this case, since the torsional rigidity of the MC cross member 20 is improved, even if the MC cross member 20 vibrates due to the vibration of the transaxle or the high voltage component, the MC cross member 20 is effectively bent or deformed. Can be prevented.

Here, the gap between the first fastening holes 64a to 64c and the inner end side of the first bracket piece 44 in the vehicle width direction, and the first fastening holes 74a, 74c and the second bracket piece 46 in the vehicle width direction. The gap between the inner end side and the first and second bracket pieces 44 and 46 is a load-bearing portion 65a to which receives a load from the first fastening bolts 66a to 66c when the first and second bracket pieces 44 and 46 are pulled outward in the vehicle width direction. It becomes 65c, 75a, 75c (see FIG. 18). In this example, among the plurality of load-bearing portions 65a to 65c, 75a, 75c, the strength of the load-bearing portions 65a, 75a located at the front is higher than the strength of the other load-bearing portions 65b, 65c, 75c. is doing. Specifically, as is clear from FIG. 18, among the three first fastening holes 64a to 64c provided in the first bracket piece 44, the central and rear first fastening holes 64a and 64c are in the vehicle width direction. The inner peripheral edge is a substantially C-shape with a break in the middle. Similarly, of the two first fastening holes 74a and 74c provided in the second bracket piece 46, the first fastening hole 74c on the rear side also has a substantially C-shape whose inner peripheral edge in the vehicle width direction is interrupted in the middle. It has become. Therefore, the strengths of the load-bearing portions 65b, 65c, 75c on the center and the rear side are significantly lower than those of the load-bearing portions 65a, 75a on the front side. With such a configuration, when the front side member 12 is bent, the first and second bracket pieces 44 and 46 are allowed to rotate and move.

That is, as described above, and as shown in FIG. 13, the front side member 12 bends inward in the vehicle width direction at a position in front of the support bracket during a minute lap collision or an oblique collision. In order for the support bracket to follow the bending of the front side member 12, as shown in FIG. 13, it is necessary to rotate the support bracket around the vertical axis so that the rear end is displaced outward in the vehicle width direction. At this time, if the periphery of the first fastening hole 64b in the center of the support bracket and the periphery of the first fastening holes 64c and 74c on the rear side are firmly connected to the MC cross member 20, the support bracket cannot rotate. .. Therefore, in this example, the peripheral edge of the first fastening hole 64b in the center and the peripheral edge of the first fastening holes 64c and 74c on the rear side are substantially C-shaped so as to be interrupted inside in the vehicle width direction. As a result, when a pulling force is applied to the support bracket outward in the vehicle width direction, the load-bearing portions 65b, 65c, 75c at the center and the rear side are easily destroyed, and the first fastening holes 64b, 64c, at the center and the rear side, The first fastening bolts 66b and 66c are removed from 74c. As a result, the support bracket can be easily rotated around the first fastening holes 64b, 74a on the front side.

In this example, in order to provide a strength difference between the load-bearing portions 65a to 65c, 75a, 75c, the peripheral edges of some of the first fastening holes 64b, 64c, 74c are substantially C-shaped. However, other forms may be used as long as the frontmost load-bearing portions 65a and 75a have higher strength than the other load-bearing portions 65b, 65c and 75c. For example, the load-bearing portions 65b, 65c, 75c on the center and the rear side may be provided with cuts or grooves extending in the vehicle width direction. Further, the widths of the load-bearing portions 65b, 65c, 75c on the center and the rear side may be smaller than those of the load-bearing portions 65a, 75a on the front side.

Next, the rotary electric machine unit 22 and the motor mount 28 will be described. FIG. 21 is a perspective view of the rotary electric machine unit 22 and the motor mount 28. As described above, the rotary electric machine unit 22 includes a rotary electric machine MG which is a drive source of the vehicle and a transmission TA. Fastening holes 23 for fastening to the motor mount 28 are formed at both ends and the upper surface of the rotary electric machine unit 22 in the width direction. The rotary electric machine unit 22 is connected to the MC cross member 20 via the right side motor mount 28R and the left side motor mount 28L.

The motor mount 28 is roughly classified into an MG side fastening portion 52 to be fastened to the rotary electric machine unit 22 and a member side fastening portion 54 to be fastened to the MC cross member 20. A fastening hole 53 for fastening to the rotary electric machine unit 22 is formed in the fastening portion 52 on the MG side.

The member-side fastening portion 54 crosses the opening 34 of the MC cross member 20 in the front-rear direction of the vehicle and is fastened to the bottom surface of the MC cross member 20. The member-side fastening portion 54 has a base portion 80 fastened to the bottom surface of the MC cross member 20, a protruding portion 82 projecting upward from the center of the base portion 80, and a projecting portion 82 further upward from the center of the protruding portion 82. It can be roughly divided into an arc portion 84 and the arc portion 84.

The vehicle front-rear dimension of the base portion 80 is larger than the distance from the rear end of the front cross portion 20F of the MC cross member 20 to the front end of the rear cross portion 20R, and the base portion 80 is the front cross portion 20F. It is fastened to the bottom surface of and the bottom surface of the rear cross portion 20R. A stud bolt 86 used for this fastening projects from the upper surface of the base portion 80. The vehicle front-rear dimension of the protrusion 82 is smaller than the distance from the rear end of the front cross portion 20F to the rear end of the rear cross portion 20R, and is larger than the front-rear dimension of the opening 34. The left side motor mount 28L is fastened to the peripheral edge of the opening 34 via the fastening hole 83 formed in the protruding portion 82. The arc portion forms a space that allows the insertion of the MG side fastening portion 52.

FIG. 22 is a schematic cross-sectional view showing a state in which the member-side fastening portion 54 of the left motor mount 28L is fastened to the MC cross member 20. Here, as is clear from FIG. 22, the base portion 80 is fastened to the MC cross member 20 across the opening 34 of the MC cross member 20 in the front-rear direction. By providing such a structure, the motor mount 28 functions as a reinforcing member of the MC cross member 20. That is, at the time of a full-wrap collision, a backward collision load may be applied to the front end of the MC cross member 20. In response to this collision load, the front cross portion 20F tends to deform in the direction of crushing the opening 34. In order for the front cross portion 20F to be deformed to the rear of the vehicle, the member side fastening portion 54 connected to the front cross portion 20F and the rear cross portion 20R needs to be compressed and deformed in the vehicle front-rear direction. Due to the shape of the fastening portion 54, compression in the vehicle front-rear direction is unlikely to occur. Therefore, according to this example, the deformation of the MC cross member 20 at the time of a full-wrap collision is effectively suppressed. In addition, if the member-side fastening portion 54 is fastened to the MC cross member 20 so as to cross the opening 34, the torsional rigidity of the MC cross member 20 is improved. As a result, vibration of the MC cross member 20 and generation of noise associated therewith in normal operation are suppressed.

Further, as is clear from FIG. 22, a protruding portion 82 of the member-side fastening portion 54 is arranged between the front cross portion 20F and the rear cross portion 20R arranged apart from each other in the front-rear direction. Therefore, when the front cross portion 20F tries to deform backward at the time of a full wrap collision, the front cross portion 20F comes into contact with the protruding portion 82. Due to this contact, further backward movement of the front cross portion 20F is restricted, and deformation of the front cross portion 20F is hindered. That is, by arranging the protruding portion 82 of the member side fastening portion 54 between the front side cross portion 20F and the rear side cross portion 20R, the deformation of the MC cross member 20 (particularly the deformation such that the opening 34 is crushed) is further improved. Effectively prevented.

Further, as is clear from FIG. 22, the stud bolt 86 for fastening the base portion 80 and the front and rear cross portions 20F and 20R is similar to the first fastening bolts 66a and 66c fastened to the support bracket. It penetrates the closed cross sections of the front and rear cross portions 20F and 20R. That is, the collar 90 is arranged in the closed cross sections of the front and rear cross portions 20F and 20R, and the stud bolt 86 and the nut 88 are the base portion 80 (motor mount 28), the lower member 38, the collar 90 and the collar 90. The upper member 36 is fastened together. As a result, the mounting rigidity of the stud bolt 86 can be improved. Further, since the torsional rigidity of the MC cross member 20 is improved, bending and deformation of the MC cross member 20 can be effectively prevented.

The high-voltage components such as the rotary electric machine unit 22, the charger 26, and the PCU 24 are all attached so that the front end thereof is behind the front end of the MC cross member 20. Therefore, the collision load at the time of a full-wrap collision is applied to the MC cross member 20 before the rotary electric machine unit 22, the charger 26, and the PCU 24. Further, in the above description, the member-side fastening portion 54 extends in a direction parallel to the vehicle front-rear direction, but the member-side fastening portion 54 is hung between the front cross portion 20F and the rear cross portion 20R. If so, it may extend in a direction inclined with respect to the vehicle front-rear direction. For example, the two member-side fastening portions 54 may be fastened to the MC cross member 20 in a substantially C-shape.

Next, the behavior of each part at the time of a frontal collision will be described. First, the behavior during a full-wrap collision in which almost the entire width of the vehicle collides with the colliding body will be described. In the case of a full-wrap collision, the collision load is input to almost the entire surface of the bumper RF14. A part of this collision load is absorbed by compressing and deforming the crash box 16. The impact load that cannot be completely absorbed by the crash box 16 is further transmitted to the front end of the front side member 12. The front side member 12 tries to withstand this impact load, but when the impact load is too large to be received by the front side member 12, the front side member 12 is deformed (bent) so as to escape from the impact load.・ Curve). In this process, the bumper RF14 moves to the rear of the vehicle, and a part of the impact load is directly from the bumper RF14 or via another member interposed between the bumper RF14 and the MC crossmember 20. May also be entered.

When a vehicle rearward collision load is applied to the MC cross member 20, the front cross portion 20F of the MC cross member 20 tends to be deformed in a direction of crushing the opening 34. However, the member-side fastening portion 54 of the motor mount 28 is connected to the front cross portion 20F and the rear cross portion 20R so as to cross the opening 34. The member-side fastening portion 54 functions as a reinforcing member that regulates deformation of the MC cross member 20 in the front-rear direction. By connecting the member-side fastening portion 54 to the front cross portion 20F and the rear cross portion 20R, the relative displacement of the two cross portions 20F and 20R is restricted, and the deformation of the MC cross member 20 is suppressed.

Further, by any chance, the stud bolt 86 and the fastening bolt 92 connecting the front cross portion 20F and the member side fastening portion 54 are damaged, and the connection between the front cross portion 20F and the member side fastening portion 54 is released. Even so, the protruding portion 82 of the member-side fastening portion 54 is interposed between the front cross portion 20F and the rear cross portion 20R. Therefore, even if the front cross portion 20F tries to move backward, the front cross portion 20F comes into contact with the protruding portion 82, and further backward movement is restricted. As a result, the deformation of the MC cross member 20 is suppressed.

Then, by suppressing the deformation of the MC cross member 20, the pinching of the high voltage cable passed through the opening 34 is effectively prevented. Further, high-voltage parts such as the rotary electric machine unit 22, the PCU 24, and the charger 26 mounted on the MC cross member 20 are also more appropriately protected.

Next, the behavior at the time of a minute lap collision or an oblique collision will be described. In this case, the impact load is applied to the gusset 18 projecting outward from the front side member 12. The impact load applied to the gusset 18 is transmitted to the side surface of the front side member 12 via the gusset 18. At this time, the stress caused by the impact load tends to concentrate on the rear end of the gusset 18 or the interrupted portion 42 of the reinforcing bead 40. As a result, the front side member 12 bends inward in the vehicle width direction at the rear end of the gusset 18 or near the break point 42 of the reinforcing bead 40. At this time, the MC cross member 20 and the front side member 12 are positively separated from each other in the vehicle width direction at the same vehicle front-rear direction position as the stress concentration portion (the rear end of the gusset 18 and the interrupted portion 42 of the reinforcing bead 40). Against. In other words, a sufficient space is secured between the MC cross member 20 and the front side member 12 for bending inward in the vehicle width direction. Therefore, according to this example, the front side member 12 can be reliably bent inward in the vehicle width direction.

Further, when the front side member 12 is bent, the fastening position between the front side member 12 and the support bracket also changes as shown in FIG. With this change in the fastening position, the peripheral edges of the first fastening holes 64b, 64c, 74c in the center and the rear side are broken and separated from the fastening bolt. As a result, the support bracket can rotate about the first fastening holes 64a and 74a on the frontmost side so as to follow the displacement of the fastening position of the front side member 12. As a result, the front side member 12 can be bent more reliably.

When the front side member bends inward in the vehicle width direction, the side surface of the MC cross member 20 is pressed inward in the vehicle width direction by the bent portion of the front side member 12. At this time, the front side member 12 tends to move not only inside the vehicle width direction but also to the rear of the vehicle. However, the bent portion of the front side member 12 is caught by the overhanging wall 62 provided on the side surface of the MC cross member 20, so that the rearward movement of the front side member 12 is effectively restricted. As a result, the collision load is more reliably transmitted from the front side member 12 to the MC cross member 20.

The impact load input to the side portion 20S on one side of the MC cross member 20 is transmitted to the side portion 20S on the opposite side via the front cross portion 20F and the rear cross portion 20R. The side portion 20S on the opposite side abuts and presses on the front side member 12 on the opposite side. As a result, the collision load is transmitted to the front side member 12 on the opposite side. The front side member 12 on the opposite side absorbs a part of the collision load and is displaced in the vehicle width direction so as to avoid the collision load. That is, the entire vehicle body is displaced in the vehicle width direction so as to escape from the collision load. As a result, occupants and high-voltage components can be effectively protected.

As is clear from the above description, according to the support structure disclosed herein and the vehicle front structure 10, the motor mount 28 is laid between the front cross portion 20F and the rear cross portion 20R. There is. As a result, deformation of the front cross portion 20F, particularly deformation such that the opening 34 is crushed, is effectively prevented. Further, if the protruding portion 82, which is a part of the motor mount 28, is located in the gap between the front cross portion 20F and the rear cross portion 20R, the motor mount 28 and the front cross portion 20F are provided by any chance. Even if the connection is released, the deformation of the front cross portion 20F is suppressed by the protruding portion 82. The configuration described so far is an example, and if the motor mount 28 is laid between the front cross portion 20F and the rear cross portion 20R, the other configurations may be appropriately changed. May be good.

For example, in the above example, the MC cross member 20 has a substantially square shape having an opening 34 in the center thereof, but if the MC cross member 20 has a front cross portion 20F and a rear cross portion 20R, the MC cross member 20 has a front cross portion 20F and a rear cross portion 20R. , Other shapes may be used. Therefore, even if the MC cross member 20 has a shape having two crossover portions extending in a substantially X shape between the front side cross portion 20F and the rear side cross portion 20R instead of the side portion 20S. good. Further, in the above description, the motor mount 28 is fastened to the bottom surface of the MC cross member 20, but may be fastened to the upper surface. For example, the motor mount 28 may be connected to the upper surface of the MC cross member 20, and the rotary electric machine unit 22 may be connected above the MC cross member 20 via the motor mount 28.

9 High voltage unit for vehicle, 10 Vehicle front structure, 11 Power unit room, 12, 112 Front side member, 16 Crash box, 18 gusset, 19 High voltage cable, 20, 120 MC cross member, 20F front cross member, 20R rear Side cross part, 20S side part, 22 rotary electric unit, 24,124 PCU, 26,126 charger, 28 motor mount, 32 support bracket, 34,121 opening, 36 upper member, 38 lower member, 40 reinforcement bead, 44 1st bracket piece, 46 2nd bracket piece, 50 collar, 52 MG side fastening part, 54 member side fastening part, 62 overhanging wall, 64a-64c, 74a, 74c first fastening hole, 65a-65c, 75a, 75c load-bearing part, 80 base part, 82 protrusion, 86 stud bolt, 90 collar, 122 rotary electric machine.

Claims (12)

A pair of front side members, each of which is spaced apart in the width direction of the vehicle and extends in the front-rear direction of the vehicle.
A cross member spanned between the pair of front side members, a front cross portion extending in the vehicle width direction, a rear cross portion provided behind the front cross portion and extending in the vehicle width direction, and a rear cross portion. With cross members including
A mount that connects a high-voltage component to the cross member, and a mount that is hung between the front cross portion and the rear cross portion.
Equipped with
An opening that penetrates in the vertical direction is formed in the center of the cross member.
The front and rear ends of the mount straddle the opening of the cross member in the front-rear direction of the vehicle and are fastened to the cross member.
The vehicle front structure is characterized by that. A pair of front side members, each of which is spaced apart in the width direction of the vehicle and extends in the front-rear direction of the vehicle.
A cross member spanned between the pair of front side members, a front cross portion extending in the vehicle width direction, a rear cross portion provided behind the front cross portion and extending in the vehicle width direction, and a rear cross portion. With cross members including
A mount that connects a high-voltage component to the cross member, and a mount that is hung between the front cross portion and the rear cross portion.
A gusset that is attached to the outer surface of each front side member in the vehicle width direction and protrudes outward in the vehicle width direction from the front side member, and the dimension in the vehicle width direction becomes smaller as the vehicle moves backward.
Equipped with
At the same vehicle front-rear direction position as the rear end of the gusset, the cross member and the front side member face each other in a state of being separated in the vehicle width direction.
At a position in the vehicle front-rear direction that is the same as the rear end of the gusset or behind the rear end of the gusset, one or more overhanging walls are provided on the outer surface of the cross member in the vehicle width direction.
The overhanging wall projects outward in the vehicle width direction from the front of the overhanging wall.
The vehicle front structure is characterized by that. The vehicle front structure according to claim 2 .
The cross member includes an upper member forming the upper surface of the cross member and a lower member forming the bottom surface of the cross member.
The upper member and the lower member are connected to each other to form a closed cross section.
The mount, the upper member, and the lower member are co-tightened with a bolt penetrating the closed cross section and a nut screwed onto the bolt.
The vehicle front structure is characterized by that. The vehicle front structure according to claim 2 or 3 .
The mount is
A base portion fastened to the bottom surface or the upper surface of the front cross portion and the rear cross portion,
A protrusion protruding from the center of the base in the vehicle height direction,
Equipped with
When the base portion is fastened to the front cross portion and the rear cross portion, the protruding portion is located in the gap between the front cross portion and the rear cross portion.
The vehicle front structure is characterized by that. The vehicle front structure according to any one of claims 2 to 4 .
A reinforcing bead that extends in the front-rear direction of the vehicle and is temporarily interrupted in the middle is provided on the end face of the front side member in the vehicle width direction.
The overhanging wall is provided at the same position as the break point of the reinforcing bead, or at a position in the vehicle front-rear direction behind the break point of the reinforcing bead.
The vehicle front structure is characterized by that. The vehicle front structure according to any one of claims 2 to 5 .
The cross member has a vehicle front structure in which the height direction dimension at the end portion in the vehicle width direction is larger than the height direction dimension at the center in the vehicle width direction. The vehicle front structure according to any one of claims 2 to 6 , further comprising:
A bracket for connecting the cross member and the front side member is provided with the cross member and the front side member separated from each other in the vehicle width direction.
The vehicle front structure is characterized by that. The vehicle front structure according to claim 7 .
The cross member includes an upper member forming the upper surface of the cross member and a lower member forming the bottom surface of the cross member.
The upper member and the lower member are connected to each other to form a closed cross section.
The bracket, the upper member, and the lower member are jointly fastened with a first fastening bolt penetrating the closed cross section and a nut screwed to the first fastening bolt.
The vehicle front structure is characterized by that. The vehicle front structure according to claim 7 or 8 .
The bracket is fastened to the cross member and the front side member at a position in the vehicle front-rear direction behind the rear end of the gusset.
The bracket is used for fastening to the cross member and has a plurality of first fastening holes arranged in the front-rear direction of the vehicle.
A load-bearing portion, which is a predetermined gap, is interposed between each first fastening hole and the inner end portion of the bracket in the vehicle width direction.
The load-bearing part located at the front has higher strength than other load-bearing parts.
The vehicle front structure is characterized by that. The vehicle front structure according to any one of claims 2 to 9 .
The vehicle front structure is characterized in that the cross member further includes a pair of side portions that connect the ends of the front cross portion and the rear cross portion to each other. A pair of mounts that can be attached to both ends of the rotary electric machine unit in the width direction,
Both ends in the vehicle width direction are fastened to a pair of front side members extending in the front-rear direction of the vehicle, the rotary electric machine unit is attached to the lower part via the pair of mounts, and a high voltage device is attached to the upper part. With cross members,
It is a support structure of a high voltage unit for vehicles, which is equipped with.
An opening that penetrates in the vertical direction is formed in the center of the cross member.
The front and rear ends of the pair of mounts are fastened to the cross member across the opening of the cross member in the front-rear direction of the vehicle.
Support structure for high voltage unit for vehicles. A pair of front side members, each of which is spaced apart in the width direction of the vehicle and extends in the front-rear direction of the vehicle.
A cross member spanned between the pair of front side members, a front cross portion extending in the vehicle width direction, a rear cross portion provided behind the front cross portion and extending in the vehicle width direction, and a rear cross portion. With cross members including
A mount that connects a high-voltage component to the cross member, and a mount that is hung between the front cross portion and the rear cross portion.
A gusset that is attached to the outer surface of each front side member in the vehicle width direction and protrudes outward in the vehicle width direction from the front side member, and the dimension in the vehicle width direction becomes smaller as the vehicle moves backward.
A bracket that connects the cross member and the front side member with the cross member and the front side member separated from each other in the vehicle width direction.
Equipped with
At the same vehicle front-rear direction position as the rear end of the gusset, the cross member and the front side member face each other in a state of being separated in the vehicle width direction.
The bracket is fastened to the cross member and the front side member at a position in the vehicle front-rear direction behind the rear end of the gusset.
The bracket is used for fastening to the cross member and has a plurality of first fastening holes arranged in the front-rear direction of the vehicle.
A load-bearing portion, which is a predetermined gap, is interposed between each first fastening hole and the inner end portion of the bracket in the vehicle width direction.
The load-bearing part located at the front has higher strength than other load-bearing parts.
The vehicle front structure is characterized by that.

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