Vehicle frame structure

Abstract

A vehicle frame structure is obtained that is formed by die casting and has vehicle frame members that ensure the required rigidity and can be fastened with bolts. [Solution] The cast body 28 is composed of a vertical wall portion 40, a plurality of ribs 42, and through holes 34. The vertical wall portion 40 is formed on the motor unit 13 side at the front of the vehicle 12 and extends in the longitudinal and vertical directions of the vehicle. The plurality of ribs 42 are erected from the vertical wall portion 40 outward in the vehicle width direction. Furthermore, the through holes 34 are provided in the vertical wall portion 40 and are formed within the area surrounded by the ribs 42. By providing ribs 42 around the through holes 34, it is possible to improve the rigidity of the vertical wall portion 40 despite the presence of the through holes 34. This makes it possible to bolt the vertical wall portion 40 to the mounting portion 36 of the motor unit 13.

Description

Technical Field

[0006]

[0001] The present invention relates to a vehicle skeleton structure.

Background Art

[0002] Patent Document 1 below discloses a technique of bolt-fastening an engine to an engine mount bracket integrally formed with a chain case manufactured by aluminum die casting. In this prior art, by integrally forming the chain case and the engine mount bracket, it is possible to reduce the manufacturing cost and weight.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Generally, when manufacturing a vehicle skeleton member by die casting, ribs and the like are formed upright along the mold extraction direction in order to increase the rigidity of the vehicle skeleton member. In addition, the vehicle skeleton member is provided with a draft gradient for releasing from the mold.

[0005] Here, when providing a fastening surface for fastening a bolt to the vehicle skeleton member along the draft gradient, considering the insertion of a fastening tool for fastening the bolt, it is necessary to reduce the height of the rib in order to avoid interference with the rib. Accordingly, there is a possibility that the rigidity of the vehicle skeleton member decreases.

[0006] In consideration of the above facts, an object of the present invention is to obtain a vehicle skeleton structure including a vehicle skeleton member formed by die casting and having a required rigidity and enabling bolt fastening.

Means for Solving the Problems

[0007] The vehicle frame structure according to the first embodiment comprises a die-cast vehicle frame member provided on the outside in the vehicle width direction of a motor unit that is located at the front or rear of the vehicle and drives the wheels, and extending in the vehicle longitudinal direction, wherein the vehicle frame member includes a vertical wall portion formed on the motor unit side and extending in the vehicle longitudinal direction and in the vehicle vertical direction, a plurality of ribs erected outward from the vertical wall portion in the vehicle width direction, and through holes formed in the region surrounded by the ribs in the vertical wall portion through which fastening members for fastening the motor unit are inserted.

[0008] The vehicle frame structure according to the first embodiment includes a vehicle frame member provided on the outside in the vehicle width direction of a motor unit that is located at the front or rear of the vehicle and drives the wheels. This vehicle frame member extends in the longitudinal direction of the vehicle and is formed by die casting.

[0009] The vehicle frame member comprises a vertical wall, multiple ribs, and through holes. The vertical wall is formed on the motor unit side of the vehicle frame member and extends in the longitudinal and vertical directions of the vehicle. The multiple ribs are erected from the vertical wall outward in the vehicle width direction. Furthermore, the through holes are provided in the vertical wall and formed within the area surrounded by the ribs.

[0010] In this way, by providing multiple ribs around the through-holes formed in the vertical wall, it is possible to improve the rigidity of the vertical wall despite the presence of through-holes.

[0011] Furthermore, in this embodiment, a fastening member is inserted through a through hole formed in the vertical wall, and the motor unit is fastened to the vehicle frame member via the fastening member and the vertical wall. For example, compared to a case where a boss or the like is erected from the vertical wall, an insertion hole is formed in the boss or the like, and the motor unit is fastened to the vehicle frame member via a fastening member, the length of the fastening member can be shortened, and the fastening strength can be improved accordingly.

[0012] The vehicle frame structure according to the second embodiment is a vehicle frame structure according to the first embodiment in which the portion surrounding the through hole is a plate thickness portion that is thicker than the plate thickness of the general portion excluding the portion surrounding the through hole.

[0013] In the vehicle frame structure according to the second embodiment, the area around the through-hole formed in the vertical wall is a plate thickness portion that is thicker than the plate thickness of the general area excluding the area around the through-hole, thereby ensuring the rigidity of the area around the through-hole (fastening portion) due to the formation of the through-hole in the vertical wall.

[0014] The third embodiment of the vehicle frame structure is the vehicle frame structure according to the first or second embodiment, wherein the inside of the rib in the vertical wall portion in which the through hole is formed is the plate thickness portion.

[0015] In the vehicle frame structure according to the third embodiment, the inside of the rib in the vertical wall portion where the through hole is formed is a plate thickness portion, which makes it possible to ensure the rigidity of the area surrounding the through hole (fastening portion) due to the formation of the through hole, including the base of the rib.

[0016] The fourth embodiment of the vehicle frame structure is a vehicle frame structure according to any one of the first to third embodiments, wherein a truss-shaped rib forming a substantially triangular shape is formed by the plurality of ribs, and the through hole is provided within the truss-shaped rib.

[0017] In the vehicle frame structure according to the fourth embodiment, a truss-like rib is formed by multiple ribs, creating a substantially triangular shape. This makes it possible to improve the rigidity of the vertical wall section compared to when multiple ribs are formed in a frame shape. Furthermore, by providing the through-hole within the truss-like rib, it is possible to improve the rigidity of the area around the through-hole (fastening area) and improve the fastening strength of the fastening member. [Effects of the Invention]

[0018] As described above, the vehicle skeletal structure according to the present invention is formed by die casting and has an excellent effect of ensuring the required rigidity and enabling bolt fastening.

Brief Description of the Drawings

[0019] [Figure 1] Fig. 8 is a perspective view of a vehicle to which the vehicle skeletal structure according to the present embodiment is applied, as viewed from the upper left front side of the vehicle. [Figure 2] Fig. 11 is an exploded perspective view of a vehicle to which the vehicle skeletal structure according to the present embodiment is applied, as viewed from the upper left front side of the vehicle. [Figure 3] Fig. 14 is an enlarged perspective view of the main part shown in Fig. 2. [Figure 4] Fig. 17 is a side view of a vehicle to which the vehicle skeletal structure according to the present embodiment is applied. [Figure 5] Fig. 20 is a schematic cross-sectional view when cut along the line A-A shown in Fig. 4. [Figure 6] Fig. 23 is a partially enlarged cross-sectional view showing a part when cut along the line B-B shown in Fig. 2.

Embodiments for Carrying Out the Invention

[0020] Hereinafter, the vehicle skeletal structure according to the embodiment of the present invention will be described with reference to the drawings. In each figure, the arrow FR appropriately shown indicates the front side in the vehicle longitudinal direction, and the arrow UP indicates the upper side in the vehicle vertical direction. The arrow RH indicates the right side in the vehicle width direction, and the arrow LH indicates the left side in the vehicle width direction. Hereinafter, when simply using the directions of front and rear, up and down, and left and right for description, unless otherwise specified, they shall indicate the front and rear in the vehicle longitudinal direction, the up and down in the vehicle vertical direction, and the left and right in the vehicle left and right direction (vehicle width direction).

[0021] <Configuration of the Vehicle Skeletal Structure> First, the configuration of the vehicle skeletal structure according to the present embodiment will be described.

[0022] Figures 1 and 2 show the front section (vehicle front) 12 of a vehicle 10 to which the vehicle frame structure according to this embodiment is applied. This vehicle 10 is an electric vehicle or fuel cell vehicle that runs on power generated by a motor unit 13. As shown in Figures 1 and 2, the vehicle front section 12 has wheelhouses 14 on the left and right sides, each extending in the longitudinal direction of the vehicle, with the front wheels (not shown) positioned on each side. The right wheelhouse 14 and the left wheelhouse 14 are connected by a cross member 16 that extends in the vehicle width direction.

[0023] Furthermore, each wheelhouse 14 is provided with a suspension tower 18 on the inside in the vehicle width direction to support the upper end of the front wheel suspension, and a front side member 20 extending in the vehicle vertical and longitudinal directions is provided below the suspension tower 18. A front pillar 22 extending in the vehicle vertical and longitudinal directions is provided on the rear side of the wheelhouse 14.

[0024] In this embodiment, for example, a pair of left and right wheelhouses 14 including a suspension tower 18 and a front side member 20, a cross member 16, and a front pillar 22 are integrally molded by die casting using an aluminum alloy, magnesium alloy, or the like (cast body 28). In this embodiment, the cast body 28 has a roughly U-shape with the front side of the vehicle open in a plan view.

[0025] In this embodiment, mounting portions (periphery of the through-hole) 30 are provided at the points where the left and right wheelhouses 14 and the cross member 16 are connected. An enlarged view of these mounting portions 30 is shown in Figure 3. As shown in Figure 3, the mounting portions 30 have through-holes 34 through which bolts (fastening members) 32 can be inserted. Note that Figure 4 shows a side view of the vehicle 10, where four through-holes 34 are formed, but in Figure 3, due to the angle of the front part 12 of the vehicle, only three through-holes 34 are shown.

[0026] On the other hand, as shown in Figures 2 and 5, the motor unit 13 is provided with a mounting portion 36 that is fastened to the mounting portion 30 on the cast body 28 side, and the mounting portion 36 has a fastening hole 38 into which a bolt 32 is screwed.

[0027] Therefore, in this embodiment, the motor unit 13 is mounted (so-called mounted) to the cast body 28 by screwing (fastening) a bolt 32, which is inserted through a through hole 34 provided in the mounting portion 30 on the cast body 28 side, into a fastening hole 38 provided in the mounting portion 36 on the motor unit 13 side. Figure 5 is a cross-sectional view taken along line AA shown in Figure 4.

[0028] Furthermore, a pair of left and right wheel wells 14 are provided with suspension members (not shown). A mounting portion is provided at the center of the front member of this suspension member, which extends in the vehicle width direction, and the motor unit 13 is supported at three points, including this mounting portion.

[0029] Incidentally, as shown in Figures 2 and 4, the wheelhouse 14 is composed of a vertical wall portion 40 that extends in the vehicle's longitudinal and vertical directions, and multiple ribs 42 are erected along the vehicle's width direction from the outer surface (outer surface) 40A of the vertical wall portion 40 in the vehicle's width direction. Figure 4 mainly shows the ribs 42 around the mounting portion 30.

[0030] Here, the multiple ribs 42 will be described in detail. In this embodiment, the front side member 20 of the cast body 28 is divided into a front 20A side and a rear 20B side along the longitudinal direction of the vehicle, and the front 20A side and the rear 20B side are separated by partition walls (ribs) 46 that extend in the vertical direction and the vehicle width direction, with the rear 20B side protruding downwards from the front 20A side.

[0031] On the front 20A side of the front side member 20, an upper wall portion (rib) 48 is provided, which constitutes the upper end of the front 20A side of the front side member 20 and extends in the vehicle longitudinal direction and vehicle width direction. Below the upper wall portion 48, a lateral wall portion (rib) 50 is provided, which extends in the vehicle longitudinal direction and vehicle width direction and is approximately parallel to the upper wall portion 48. Furthermore, below the lateral wall portion 50, a lower wall portion (rib) 52 is provided, which constitutes the lower end of the front 20A side of the front side member 20 and extends in the vehicle longitudinal direction and vehicle width direction and is approximately parallel to the lateral wall portion 50.

[0032] Furthermore, the rear end of the lower wall 52 is provided with an inclined wall 54 that slopes downward towards the rear of the vehicle as it approaches the rear of the vehicle, and this inclined wall 54 is connected to the partition wall 46. In addition, multiple vertical ribs 56 are provided between the upper wall 48 and the side wall 50, and between the side wall 50 and the lower wall 52, along the vertical direction of the vehicle.

[0033] On the other hand, on the rear 20B side of the front side member 20, an upper wall portion (rib) 58 is provided that connects to the upper wall portion 48 on the front 20A side of the front side member 20, forming the upper end on the rear 20B side of the front side member 20 and extending in the vehicle longitudinal direction and vehicle width direction. Furthermore, on the lower side of the upper wall portion 58, lateral wall portions (ribs) 60 and 62 are provided that connect to the lateral wall portion 50 and the lower wall portion 52 on the front 20A side of the front side member 20, respectively, and extend in the vehicle longitudinal direction and vehicle width direction.

[0034] Furthermore, a rib portion 64 is provided below the rib portion 62, extending in the vehicle's longitudinal direction and vehicle width direction, and is approximately parallel to the rib portion 62. Below the rib portion 64, a lower rib portion 66 is provided, forming the lower end of the rear 20B side of the front side member 20, and extending in the vehicle's longitudinal direction and vehicle width direction, and is approximately parallel to the rib portion 64.

[0035] Furthermore, between the upper wall 58 and the side wall 60, the side wall 60 and the side wall 62, the side wall 62 and the side wall 64, and the side wall 64 and the lower wall 52, there are multiple upward-sloping ribs (ribs) 68 that slope upward towards the rear of the vehicle, and downward-sloping ribs (ribs) 70 that slope downward towards the rear of the vehicle. The upward-sloping ribs 68 and the downward-sloping ribs 70 are provided continuously, forming an apparent truss structure between the upper wall 58, the side wall sections 60, 62, 64, and the lower wall 66.

[0036] As mentioned above, in this embodiment, the mounting portion 30 of the cast body 28 is provided with four through holes 34. Of the four through holes 34, through holes 34A and 34B, located on the front portion 20A side of the mounting portion 30, are positioned on the front portion 20A side of the front side member 20. Also, through holes 34C and 34D, located on the rear portion 20B side of the mounting portion 30, are positioned on the rear portion 20B side of the front side member 20.

[0037] Figure 6 is a partially enlarged cross-sectional view showing an enlarged portion of the material when cut along the BB line shown in Figure 2. In this embodiment, as shown in Figure 6, the peripheral portion (mount portion 30) of the through hole 34 is a plate thickness portion 80 with a plate thickness t greater than the plate thickness t' of the general portion 44 excluding the peripheral portion of the through hole 34. In addition, in this embodiment, a rib 42 is provided on the peripheral portion of the through hole 34. Note that in this embodiment, the shape of the rib 42 provided on the peripheral portion of the through hole 34 differs between the through holes 34A, 34B and the through holes 34C, 34D.

[0038] For example, the through-hole 34A is provided within a rectangular rib 72 composed of a horizontal wall 50, a lower wall 52, a vertical rib 56, and a partition wall 46. The through-hole 34B is provided within a rectangular rib 74 composed of a lower wall 52, an inclined wall 54, a vertical rib 56, and a partition wall 46.

[0039] On the other hand, the through-hole 34C is provided within the truss-shaped rib 76, which is composed of the side wall portion 60, the side wall portion 62, the upward inclined rib 68, and the downward inclined rib 70. The through-hole 34D is provided within the truss-shaped rib 78, which is composed of the side wall portion 62, the side wall portion 64, the downward inclined rib 70, and the upward inclined rib 68.

[0040] Furthermore, in this embodiment, the inside of the ribs 42 formed around the through-hole 34 is the plate thickness portion 80. That is, the inside of the rectangular rib 72 in which the through-hole 34A is formed, the inside of the rectangular rib 74 in which the through-hole 34B is formed, the inside of the truss-shaped rib 76 in which the through-hole 34C is formed, and the inside of the truss-shaped rib 78 in which the through-hole 34D is formed are all plate thickness portions 80.

[0041] In this embodiment, as shown in Figure 5, the bolt 32 is inserted into the through hole 34 formed in the mounting portion 30 of the cast body 28, and then the bolt 32 is screwed into the fastening hole 38 formed in the mounting portion 36 of the motor unit 13. The bolt 32 is fastened into the fastening hole 38 using a fastening tool such as an impact wrench.

[0042] <Function and Effects of Vehicle Frame Structure> Next, the operation and effects of the vehicle frame structure according to this embodiment will be described.

[0043] In this embodiment, as shown in Figures 1 to 3, the front part 12 of the vehicle to which the vehicle frame structure is applied is formed by die casting, and the cast body 28 is composed of vertical wall portions 40, a plurality of ribs 42 and through holes 34.

[0044] The vertical wall portion 40 is formed on the motor unit 13 side of the front part 12 of the vehicle and extends in the longitudinal and vertical directions of the vehicle. The multiple ribs 42 are erected from the vertical wall portion 40 outward in the vehicle width direction. Furthermore, the through hole 34 is provided in the vertical wall portion 40 and is formed within the area surrounded by the ribs 42.

[0045] Thus, in this embodiment, by providing ribs 42 around the through-hole 34, it is possible to improve the rigidity of the vertical wall portion 40 despite the presence of the through-hole 34.

[0046] Furthermore, in this embodiment, a bolt 32 is inserted through a through hole 34 formed in the vertical wall portion 40, and the mounting portion 36 of the motor unit 13 is fastened to the mounting portion 30 of the cast body 28 that constitutes the front part 12 of the vehicle via the bolt 32 and the vertical wall portion 40.

[0047] Then, bolts 32 are inserted through the through holes 34, and the mounting portion 36 of the motor unit 13 is fastened to the mounting portion 30 of the cast body 28 that constitutes the front part 12 of the vehicle via the bolts 32 and the vertical wall portion 40.

[0048] For example, compared to a case where a boss or the like is erected from the vertical wall portion 40 (though not shown in the diagram), and through holes are formed in the boss or the like to fasten the motor unit 13 to the cast body 28 via bolts 32, the length of the bolts 32 can be shortened, thereby improving the fastening strength. In other words, in this embodiment, the cast body 28 formed by die casting can be fastened with bolts while ensuring the required rigidity.

[0049] Therefore, in this embodiment, even if the height of the rib is made small in the mounting portion 30 of the cast body 28 to avoid interference between the fastening tool for fastening the bolt 32 and the rib, the rigidity required for mounting the motor unit 13 is ensured by the draft angle for releasing the cast body from the mold. For this reason, in this embodiment, it is not necessary to provide spacers or the like to ensure rigidity to the mounting portion 36 of the motor unit 13, and it is possible to fasten the bolts directly.

[0050] In this way, by directly fastening the motor unit 13 to the cast body 28 via bolts 32, the mounting structure of the motor unit 13 can be simplified compared to when it is fixed via brackets or the like.

[0051] Furthermore, in this embodiment, the area surrounding the through-hole 34 (mounting portion 30) is a plate thickness portion 80 with a plate thickness t greater than the plate thickness t' of the general portion 44 excluding the area surrounding the through-hole 34. This makes it possible to ensure the rigidity of the mounting portion 30 by forming the through-hole 34 in the vertical wall portion 40 in this embodiment.

[0052] Furthermore, in this embodiment, the inside of the rib 42 in the vertical wall portion 40 where the through hole 34 is formed is the plate thickness portion 80. This makes it possible to ensure the rigidity of the mounting portion 30, including the base portion of the rib 42, by forming the through hole 34.

[0053] To briefly explain the through-holes 34 and ribs 42, the through-holes 34A and 34B of the mounting portion 30 are provided within the rectangular ribs 72 and 74, respectively, while the through-holes 34C and 34D are provided within the truss-shaped ribs 76 and 78, respectively.

[0054] As described above, in this embodiment, truss-shaped ribs 76 and 78 are formed by multiple ribs 42, creating a substantially triangular shape. This makes it possible to improve the rigidity of the vertical wall portion 40 compared to when the multiple ribs 42 are formed in a frame shape. Furthermore, by providing the through holes 34C and 34D within the truss-shaped ribs 76 and 78, the rigidity of the mounting portion 30 is improved, and the fastening strength by the bolts 32 is improved.

[0055] In addition, rectangular ribs 72 and 74 are provided around the through holes 34A and 34B, respectively, but truss-shaped ribs 76 and 78 may also be formed instead of the rectangular ribs 72 and 74.

[0056] In the embodiments described above, an example of application to the front part 12 of the vehicle frame structure has been explained, but it goes without saying that it may also be applied to the rear part of the vehicle.

[0057] Furthermore, the present invention is not limited to the embodiments described above, and can be implemented in various forms without departing from the spirit of the invention. [Explanation of symbols]

[0058] 10 vehicles 12 Front of the vehicle 13 Motor Unit 28 Cast body (vehicle frame component) 30 Mounting section (periphery of the through hole) 32 bolts (fastening members) 34 Through holes 40 Vertical wall section 42 Ribs 44 General section 46 Sectional Walls (Ribs) 48 Upper wall section (rib) 50 Side wall section (rib) 52 Lower wall section (rib) 54. Inclined wall (rib) 56 Vertical ribs (ribs) 58 Upper wall section (rib) 60 Side wall section (rib) 62 Side wall section (rib) 64 Side wall section (rib) 66 Lower wall section (rib) 68 Upward-sloping rib (rib) 70 Downward-sloping rib (rib) 72 Rectangular ribs (ribs) 74 Rectangular Ribs (Ribs) 76 Truss-shaped ribs (ribs) 78 Truss-shaped rib (rib) 80 Thick part t Plate thickness (plate thickness around the through hole) t' Plate thickness (plate thickness of the general section)

Claims

1. A vehicle frame member is provided on the outside in the vehicle width direction of a motor unit that is located at the front or rear of the vehicle and drives the wheels, and extends in the vehicle longitudinal direction, and is made of die-cast material. The aforementioned vehicle frame member is A vertical wall portion formed on the motor unit side and extending in the vehicle's longitudinal direction and vertical direction, Multiple ribs are erected from the aforementioned vertical wall portion toward the outside in the vehicle width direction, A through hole formed within the region surrounded by the ribs in the vertical wall portion, through which a fastening member for fastening the motor unit is inserted, A vehicle frame structure that includes the following components.

2. The vehicle frame structure according to claim 1, wherein the portion surrounding the through-hole is a plate thickness portion that is thicker than the plate thickness of the general portion excluding the portion surrounding the through-hole.

3. The vehicle frame structure according to claim 2, wherein the inside of the rib in the vertical wall portion in which the through hole is formed is the plate thickness portion.

4. The vehicle frame structure according to claim 1, wherein a truss-shaped rib forming a substantially triangular shape is formed by the plurality of ribs, and the through hole is provided within the truss-shaped rib.

Images