JP2019196068A - Vehicle front part structure - Google Patents

Abstract

To inhibit a connection portion of a tie rod from being fractured at an initial timing of a small overlap offset collision.SOLUTION: A vehicle front part structure includes a suspension member 12, a lower arm 14, a front wheel 16, a steering gear box 18 operated to change the orientation of the front wheel 16, and a tie rod 20 connecting the front wheel 16 to the steering gear box 18. Further, the vehicle front part structure includes a side rail 22 disposed outward of the suspension member 12 in a vehicle width direction to be located on the front side of a vehicle. The side rail 22 includes: an upper connection portion 48 and a lower connection portion 50 respectively connected to vehicle upper and lower surfaces of a portion 38 located outward of the suspension member 12 in the vehicle width direction; and a lower arm opposed portion 52 disposed opposed to at least a portion of the lower arm 14 in a vehicle front to back direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle front structure.

  In the following Patent Document 1, a vehicle in which a tie rod pressing member attached to a front subframe presses a tie rod at the time of a small overlap offset collision in which an obstacle collides only with an end in the vehicle width direction of the vehicle. A (car body) front structure is disclosed. In the vehicle front structure described in this document, the tie rod is pressed and deformed by the tie rod pressing member, so that the front wheel is in the toe-in direction (the front end of the front wheel is inward in the vehicle width direction and the rear end is in the vehicle width direction outside). ) To prevent the front wheel from colliding with the side sill.

JP2013-203112A

  By the way, if the connecting portion of the tie rod is broken at the initial stage of the small overlap offset collision, it is difficult to control the behavior of the front wheel after the connecting portion of the tie rod is broken.

  An object of the present invention is to obtain a vehicle front structure that can prevent the tie rod connecting portion from breaking at the initial stage of a small overlap offset collision in consideration of the above fact.

  The vehicle front structure according to claim 1 includes a suspension member disposed on a vehicle lower side in a front portion of the vehicle, a lower arm attached to a portion of the suspension member on the outer side in the vehicle width direction, and a vehicle width direction of the lower arm. A front wheel rotatably supported in an outer portion; a steering gear box whose direction of the front wheel is changed by being actuated; and the front wheel and the steering gear provided between the front wheel and the steering gear box. A tie rod that connects the box and a vehicle front side of a portion of the suspension member in the vehicle width direction on the vehicle front side, and a vehicle upper side surface and a vehicle lower side surface of the suspension member in the vehicle width direction outer side, respectively. The upper and lower joints to be joined are opposed to at least a part of the lower arm in the vehicle longitudinal direction. And includes a side rail, a having a lower arm facing portion disposed Te.

  According to the vehicle front structure according to claim 1, when the load due to the small overlap offset collision is transmitted to the side rail and the suspension member, the peripheral portions of the upper joint portion and the lower joint portion of the suspension member and the side rail are Stress increases. And when the stress of the peripheral part of the upper side junction part and lower side junction part in a suspension member and a side rail exceeds a predetermined value, the said part will deform | transform from the part where the said stress increased. As a result, the lower arm facing portion of the side rail moves to the vehicle rear side and comes into contact with the lower arm. As a result, the displacement of the lower arm and the front wheels toward the vehicle front side is restricted. Thereby, the load added to the connection part of a tie rod is reduced.

  The vehicle front structure according to the present invention has an excellent effect that it is possible to prevent the connecting portion of the tie rod from breaking at the initial stage of the small overlap offset collision.

It is the top view which simplified and showed the front part of the vehicle. It is sectional drawing which shows the cross section of the front part of the vehicle cut | disconnected along the 2-2 line shown by FIG. 1, and has shown the state before a collision. It is sectional drawing which shows the cross section of the front part of the vehicle cut | disconnected along the 2-2 line shown by FIG. 1, and has shown the state at the time of a collision. It is a top view corresponding to FIG. 1 which shows the front part of a vehicle, and has shown the state at the time of a collision. It is a top view showing the front part of the vehicle to which the vehicle front part structure of the first embodiment is applied. It is a top view which expands and shows the rear-end part vicinity of the side rail in the front part of a vehicle. It is sectional drawing which shows the cross section of the front part of the vehicle cut | disconnected along 7-7 line shown by FIG. 5, and has shown the state before a collision. It is a top view corresponding to Drawing 5 showing the front part of vehicles, and shows the state at the time of a collision. It is sectional drawing which shows the cross section of the front part of the vehicle cut | disconnected along 7-7 line shown by FIG. 5, and has shown the state at the time of a collision with the dashed-two dotted line. It is a sectional side view corresponding to FIG. 7 which shows the front part of the vehicle to which the vehicle front part structure of 2nd Embodiment was applied, and has shown the state before a collision. It is a top view which shows the front part of the vehicle to which the vehicle front part structure of 2nd Embodiment was applied, and has shown the state before a collision. It is a sectional side view corresponding to Drawing 7 showing the front part of vehicles to which the vehicles front part structure of a 2nd embodiment was applied, and shows the state after a collision. It is a top view corresponding to Drawing 11 which shows the front part of vehicles to which vehicles front part structure of a 2nd embodiment was applied, and shows the state after a collision. It is a top view which shows the front part of the vehicle to which the vehicle front part structure of 3rd Embodiment was applied, and has shown the state before a collision. It is a schematic diagram which shows typically the front part of the vehicle cut | disconnected along the 15-15 line shown by FIG. 14, and has shown the state before a collision. It is a top view which shows the front part of the vehicle to which the vehicle front part structure of 3rd Embodiment was applied, and has shown the state at the time of a collision. It is a schematic diagram corresponding to FIG. 15, and has shown the state at the time of a collision. It is a top view which shows the front part of the vehicle to which the vehicle front part structure of 4th Embodiment was applied, and has shown the state before a collision.

(Schematic configuration of the embodiment of the present invention)
The schematic configuration of the embodiment of the present invention will be described with reference to FIGS. Note that an arrow FR appropriately shown in each drawing indicates the front side in the vehicle front-rear direction, an arrow UP indicates an upper side in the vehicle vertical direction, and an arrow OUT indicates an outer side in the vehicle width direction.

  As shown in FIG. 1, a vehicle front portion 10 to which the present invention is applied includes a suspension member 12 disposed on the vehicle lower side of a pair of left and right front side members (not shown), and the vehicle width direction of the suspension member 12 And a lower arm 14 attached to the outer portion. Further, on the front portion 10 of the vehicle, there are a front wheel 16 that is rotatably supported at a portion on the outer side in the vehicle width direction of the lower arm 14, and a steering gear box 18 whose direction of the front wheel 16 is changed by being actuated. Is provided. Further, a tie rod 20 that is provided between the front wheel 16 and the steering gear box 18 and connects the front wheel 16 and the steering gear box 18 is provided at the front portion 10 of the vehicle. Further, the front portion 10 of the vehicle includes a side rail 22 whose end on the vehicle rear side is joined to the lower arm 14. In FIG. 1, only one side in the vehicle width direction of the front portion 10 of the vehicle is shown, and the other side in the vehicle width direction is not shown.

  The suspension member 12 is formed in a rectangular shape whose longitudinal direction is the vehicle width direction when viewed from the upper side or the lower side of the vehicle. As an example, as shown in FIG. 2, the suspension member 12 is manufactured by joining an upper member 24 and a lower member 26 formed using a thick steel plate material or the like. As shown in FIG. 1, both end portions of the suspension member 12 in the vehicle width direction are lower arm attachment portions 28 to which lower arms 14 described later are attached.

  The lower arm 14 is formed in a substantially Y shape when viewed from above or below the vehicle. The inner part in the vehicle width direction of the lower arm 14 is a front attachment part 30 and a rear attachment part 32 attached to the lower arm attachment part 28 of the lower arm 14. By attaching the front side attachment portion 30 and the rear side attachment portion 32 to the lower arm attachment portion 28, the lower arm 14 can tilt with respect to the suspension member 12. Further, the lower arm 14 includes an arm portion 34 that extends outward from the front mounting portion 30 and the rear mounting portion 32 in the vehicle width direction. A front wheel 16 is rotatably supported at an outer end portion of the arm portion 34 in the vehicle width direction via a knuckle, a hub, or the like (not shown).

  The steering gear box 18 is used to decelerate and transmit the rotation of a steering (not shown) or the rotation of a motor operated by a vehicle occupant to the tie rod 20. In the present embodiment, the steering gear box 18 is fixed to the central portion of the suspension member 12 in the vehicle width direction.

  The tie rod 20 is formed in a rod shape whose longitudinal direction is the vehicle width direction. At both ends of the tie rod 20 in the longitudinal direction, connecting portions 36 such as ball joints are provided. One side connecting portion 36 is connected to the steering gear box 18, and the other side connecting portion is connected to a knuckle (not shown). Then, the tie rod 20 is displaced via the steering gear box 18 so that the direction of the front wheels 16 changes.

  The side rail 22 is provided on the vehicle front side of the portion 38 on the outer side in the vehicle width direction of the suspension member 12. In the present embodiment, a pair of left and right side rails 22 arranged at intervals in the vehicle width direction are provided, and end portions on the vehicle front side of the pair of left and right side rails 22 are interposed via a cross member 40. It is connected in the vehicle width direction.

  As shown in FIG. 2, the end portion 42 on the vehicle rear side of the side rail 22 has a substantially U-shaped cross section in which the vehicle rear side is opened in a cross-sectional view cut along the vehicle front-rear direction and the vertical direction. . An end portion 42 of the side rail 22 on the vehicle rear side is joined to a surface 44 on the vehicle upper side and a surface 46 on the vehicle lower side of a portion 38 on the vehicle width direction outer side of the suspension member 12 via welding or a fastening member, respectively. The upper joint portion 48 and the lower joint portion 50 are provided. The joint strength between the vehicle upper side surface 44 and the upper joint portion 48 of the suspension member 12 outer portion 38 in the vehicle width direction and the joint strength between the vehicle lower side surface 46 and the lower joint portion 50 will be described later. It is set appropriately considering the behavior at the time of small overlap offset collision.

  Further, an end portion 42 on the vehicle rear side of the side rail 22 includes a lower arm facing portion 52 disposed between the upper joint portion 48 and the lower joint portion 50 so as to face a part of the lower arm 14 in the vehicle front-rear direction. I have.

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

  When the vehicle to which the vehicle front structure described above is applied makes a small overlap offset collision with the obstacle 54, as shown in FIGS. 3 and 4, the load due to the small overlap offset collision causes the cross member 40 (FIG. 1)) to the side rail 22 and the suspension member 12. Then, the stress of the peripheral part of the upper side junction part 48 and the lower side junction part 50 in the suspension member 12 and the side rail 22 increases. And when the stress of the peripheral part of the upper side junction part 48 and the lower side junction part 50 in the suspension member 12 and the side rail 22 exceeds a predetermined value, the said part will deform | transform from the part where the said stress increased. As a result, the lower arm facing portion 52 of the side rail 22 moves toward the vehicle rear side, thereby coming into contact with the lower arm 14, and the displacement of the lower arm 14 and the front wheel 16 toward the vehicle front side is restricted. As a result, it is possible to prevent the connecting portion 36 of the tie rod 20 from breaking at the initial stage of the small overlap offset collision.

(Vehicle front structure according to the first embodiment)
Next, the front portion 56 of the vehicle to which the vehicle front portion structure according to the first embodiment of the present invention is applied will be described with reference to FIGS. In the front part 56 of the vehicle, the members and parts corresponding to the front part 10 of the vehicle are denoted by the same reference numerals as those of the members and parts constituting the front part 10 of the vehicle, and description thereof is omitted. There is.

  As shown in FIG. 5 to FIG. 7, the side rail 22 that constitutes a part of the front portion 56 of the vehicle of the present embodiment is an upper rail member 58 formed by subjecting a steel plate material to press working or the like. And the lower rail member 60 are joined together. As shown in FIGS. 5 and 6, the end portion 42 on the vehicle rear side of the side rail 22 is a first extending portion 62 that is inclined toward the vehicle front side toward the vehicle width direction outer side. Further, in the side rail 22, the vehicle front side portion of the first extension portion 62 has an inclination angle that is greater than the inclination angle of the first extension portion 62 with respect to the vehicle width direction. The second extending portion 64 is used. Further, an outer portion in the vehicle width direction at a boundary portion between the first extending portion 62 and the second extending portion 64 is a convex portion 66 that is convex toward the lower arm 14 side. Furthermore, the vehicle width direction inner side part in the boundary part of the 1st extension part 62 and the 2nd extension part 64 becomes the concave-shaped part 68 depressed toward the lower arm 14 side. In the present embodiment, in the vicinity of the rear end 70 and the convex portion 66 of the side rail 22, the vehicle upper side surface 44 and the upper joint portion 48 of the front end portion 38 </ b> F of the portion 38 outside the vehicle width direction of the suspension member 12. Are joined by spot welding. Similarly, the vehicle lower side surface 46 of the front end portion 38F of the portion 38 on the vehicle width direction outer side of the suspension member 12 and the lower joint portion 50 are joined by spot welding. A portion where spot welding has been performed is indicated by reference numeral 72.

  When the vehicle to which the vehicle front structure of the present embodiment described above is applied makes a small overlap offset collision with the obstacle 54 (see FIG. 1), as shown in FIGS. A load due to the collision is transmitted to the side rail 22 and the suspension member 12. Then, the stress of the peripheral part of the upper side junction part 48 and the lower side junction part 50 in the suspension member 12 and the side rail 22 increases. In particular, the stress of the spot weld 72 increases. And when the stress of the spot welded part 72 exceeds a predetermined value, the spot welded part 72 is broken. As a result, the lower arm facing portion 52 of the side rail 22 moves toward the vehicle rear side, thereby coming into contact with the lower arm 14, and the displacement of the lower arm 14 and the front wheel 16 toward the vehicle front side is restricted. As a result, it is possible to prevent the connecting portion 36 of the tie rod 20 from breaking at the initial stage of the small overlap offset collision.

(Vehicle front structure according to the second embodiment)
Next, a vehicle front portion 74 to which a vehicle front portion structure according to a second embodiment of the present invention is applied will be described with reference to FIGS. In the front part 74 of the vehicle, members and portions corresponding to the front part 56 of the vehicle according to the first embodiment described above are denoted by the same reference numerals as the members and parts constituting the front part 56 of the vehicle. Description may be omitted.

  As shown in FIGS. 10 to 13, the front part 74 of the vehicle to which the vehicle front structure according to the present embodiment is applied is the front part of the vehicle to which the vehicle front structure according to the first embodiment is applied. Although it is basically the same as the configuration of 56, it is characterized in that the first extending portion 62 is bent and deformed at the time of a small overlap offset collision. When the vehicle to which the vehicle front structure of the present embodiment is applied makes a small overlap offset collision with an obstacle, as shown in FIGS. 12 and 13, the load due to this small overlap offset collision causes the side rail 22 and It is transmitted to the suspension member 12. Then, the stress of the peripheral part of the upper side junction part 48 and the lower side junction part 50 in the suspension member 12 and the side rail 22 increases. In particular, the stress of the spot weld 72 increases. And when the stress of the spot welded part 72 exceeds a predetermined value, the spot welded part 72 is broken. As a result, the lower arm facing portion 52 of the side rail 22 moves toward the vehicle rear side, thereby coming into contact with the lower arm 14, and the displacement of the lower arm 14 and the front wheel 16 toward the vehicle front side is restricted. As a result, it is possible to prevent the connecting portion 36 of the tie rod 20 from breaking at the initial stage of the small overlap offset collision. Further, when the side rail 22 is further pressed toward the vehicle rear side in a state where the lower arm facing portion 52 of the side rail 22 is in contact with the lower arm 14, an intermediate portion of the first extending portion 62 in the vehicle width direction is the lower arm 14. The first extending portion 62 is bent and deformed. Thereby, the energy of a small overlap offset collision can be absorbed. In FIG. 13, the starting point of the bending deformation of the first extending portion 62 is indicated by reference numeral 76.

(Vehicle front structure according to the third embodiment)
Next, a vehicle front portion 78 to which the vehicle front portion structure according to the third embodiment of the present invention is applied will be described with reference to FIGS. In the front part 78 of the vehicle, the members and portions corresponding to the front parts 10, 56, 74 of the vehicle are denoted by the same reference numerals as the members and parts constituting the front parts 10, 56, 74 of the vehicle. Therefore, the description thereof may be omitted.

  As shown in FIGS. 14 and 15, the present embodiment is characterized in that the suspension member 12 and the side rail 22 are joined via a fastening member 80 such as a bolt and a nut. Specifically, as shown in FIG. 15, a fastening member 80 is inserted into the upper member 24 and the lower member 26 of the suspension member 12 and the upper joint portion 48 and the lower joint portion 50 of the side rail 22. A fastening member insertion hole 82 is formed. Further, the upper member 24 and the lower member 26 of the suspension member 12 are provided with a lightening hole 84 disposed on the vehicle rear side of the fastening member insertion hole 82 and spaced from the fastening member insertion hole 82. Is formed. A portion between the fastening member insertion hole 82 and the lightening hole 84 in the upper member 24 and the lower member 26 of the suspension member 12 is a planned fracture portion 86 that breaks at the time of a small overlap offset collision.

  When the vehicle to which the vehicle front structure of the present embodiment described above is applied makes a small overlap offset collision with an obstacle, as shown in FIGS. 16 and 17, the load due to the small overlap offset collision is changed to the side. It is transmitted to the rail 22 and the suspension member 12. Then, the stress of the peripheral part of the upper side junction part 48 and the lower side junction part 50 in the suspension member 12 and the side rail 22 increases. In particular, the stress at the planned fracture portion 86 of the upper member 24 and the lower member 26 of the suspension member 12 increases. When the stress of the planned fracture portion 86 exceeds a predetermined value, the planned fracture portion 86 breaks. As a result, the lower arm facing portion 52 of the side rail 22 moves toward the vehicle rear side, thereby coming into contact with the lower arm 14, and the displacement of the lower arm 14 and the front wheel 16 toward the vehicle front side is restricted. As a result, it is possible to prevent the connecting portion 36 of the tie rod 20 from breaking at the initial stage of the small overlap offset collision. In a state where the lower arm facing portion 52 of the side rail 22 is in contact with the lower arm 14, a part of the fastening member 80 is disposed in the lightening holes 84 of the upper member 24 and the lower member 26 of the suspension member 12. It has become.

(Vehicle front structure according to the fourth embodiment)
Next, a vehicle front portion 88 to which the vehicle front portion structure according to the fourth embodiment of the present invention is applied will be described with reference to FIG. In the front part 78 of the vehicle, the members and portions corresponding to the front parts 10, 56, 74 of the vehicle are denoted by the same reference numerals as the members and parts constituting the front parts 10, 56, 74 of the vehicle. Therefore, the description thereof may be omitted.

  As shown in FIG. 18, in this embodiment, a gap filling portion 90 that protrudes from the vicinity of the convex portion 66 of the side rail 22 toward the lower arm 14 side is provided, so that the lower arm facing portion 52 and the lower arm 14 are provided. It is characterized in that the interval between and is narrowed. As a result, the lower arm facing portion 52 can be quickly brought into contact with the lower arm 14 at the time of the small overlap offset collision.

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

12 Suspension member 14 Lower arm 16 Front wheel 18 Steering gear box 20 Tie rod 22 Side rail 48 Upper joint 50 Lower joint 52 Lower arm facing part

Claims (1)

A suspension member disposed on the vehicle lower side at the front of the vehicle;
A lower arm attached to an outer portion of the suspension member in the vehicle width direction;
A front wheel rotatably supported at a portion of the lower arm in the vehicle width direction;
A steering gear box that is actuated to change the direction of the front wheels,
A tie rod that is provided between the front wheel and the steering gear box and connects the front wheel and the steering gear box;
An upper joint portion and a lower joint portion disposed on the vehicle front side of the vehicle width direction outer portion of the suspension member and bonded to the vehicle upper surface and the vehicle lower surface of the suspension member outer width portion, respectively. A side rail having a side joining portion, and a lower arm facing portion disposed to face at least a part of the lower arm in the vehicle front-rear direction;
Vehicle front structure with