Vehicle body structure
By designing side beams and connecting members with closed cross sections to form two load paths, the problem of improper load input during small overlap collisions in the prior art is solved, and the collision energy absorption efficiency of the front part of the vehicle body is improved.
Patent Information
- Application Number
- CN202280095312.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2022-04-27
- Publication Date
- 2024-12-10
AI Technical Summary
In the case of a small overlapping collision, the collision load is not properly input to the side beams and connecting members, resulting in the loading path not functioning effectively.
A side beam with a closed cross section, a hood bracket and a connecting member are designed, wherein the front portion of the side beam has a constant width, the rear width gradually decreases, and an inclined surface is formed at the transition portion, and the front end of the connecting member is engaged with the side beam to form a Two loading paths are used to effectively fight collision loads.
By properly branching the collision load, the two loading paths are used to effectively resist the collision load, which improves the collision energy absorption efficiency of the front of the vehicle body and reduces the need for strengthening the car.
Smart Images
Figure CN119110779A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to vehicle body construction. Background Art
[0002] It is desirable to have a vehicle body structure that is effective against a collision mode in which an impact force is input to a corner of the front of a vehicle, a so-called small overlap collision (also called a small offset collision). Patent document 1 below discloses a vehicle body front structure that takes small overlap collision into consideration. The vehicle body front structure disclosed in patent document 1 includes: a side beam, the top end of which expands laterally outward; a hood bracket that extends forward above the side beam; and a connecting member that extends obliquely downward from the front end of the hood bracket.
[0003] The side beam is referred to as a side frame in Patent Document 1. The hood bracket and the connecting member are collectively referred to as a side beam in Patent Document 1. The hood bracket and the connecting member are referred to as a top beam and a bottom beam (of the side beam) in Patent Document 1, respectively.
[0004] The front end of the side beam and the front end of the connecting member are arranged in a transverse arrangement, and an energy absorption box is arranged in front of them. A bumper reinforcement is installed at the front end of the energy absorption box. The collision load during a small overlap collision is input to both the side beam and the connecting member through the energy absorption box, and is transmitted through two loading paths. The side beam and the connecting member not only transmit the collision load, but also absorb the collision energy of the collision load by their own crushing while transmitting the collision load.
[0005] Prior art literature
[0006] Patent Literature
[0007] Patent Document 1: Japanese Patent Application Publication No. 2017-100555 Summary of the invention
[0008] Problem that the invention aims to solve
[0009] In the vehicle body front structure disclosed in Patent Document 1, the front end of the side beam that expands laterally outward is arranged in parallel with the front end of the connecting member. Therefore, there is a possibility that the collision load during a small overlap collision is not properly input to both the side beam and the connecting member, and the two loading paths do not function effectively. Therefore, an object of the present invention is to provide a vehicle body structure that can properly branch the collision load and effectively resist the collision load using two loading paths.
[0010] Solutions for solving problems
[0011] The vehicle body structure characterized by the present invention comprises: a side beam having a closed cross section; a hood bracket having a closed cross section; and a connecting member extending downward from the front end of the hood bracket and having a closed cross section. The side beam comprises: a front portion having a constant first horizontal width; a rear portion having a second horizontal width smaller than the first horizontal width; and a transition portion provided between the front portion and the rear portion, the horizontal width of which gradually changes from the first horizontal width to the second horizontal width. An inclined surface facing laterally outward and toward the rear is formed on the outer side surface of the transition portion, and the front end of the connecting member is joined to the side beam at the inclined surface.
[0012] Effects of the Invention
[0013] According to the above-mentioned features, the collision load can be appropriately branched to the side members and the connecting members, and the collision load can be effectively counteracted by two load paths. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a perspective view of the vehicle body structure according to the embodiment.
[0015] Figure 2 It is an enlarged partial stereoscopic view of the above-mentioned vehicle body structure.
[0016] Figure 3 It is an enlarged exploded perspective view of the above-mentioned vehicle body structure.
[0017] Figure 4 It is a bottom view of the above-mentioned vehicle body structure.
[0018] Figure 5 It is a bottom perspective view of the above-mentioned vehicle body structure.
[0019] Figure 6 yes Figure 5 VI-VI line section view. DETAILED DESCRIPTION
[0020] The vehicle body structure of the embodiment will be described below with reference to the accompanying drawings. The vehicle body structure of the embodiment is symmetrically constructed on the left and right sides of the vehicle body. Therefore, the structure on the left side will be described below as an example. Figure 1 to Figure 4 The vehicle of this embodiment is a hybrid electric vehicle (HEV), and a motor room for accommodating an internal combustion engine and an electric generator for generating electricity and an electric generator for driving the vehicle is provided at the front of the vehicle body.
[0021] like Figure 1 As shown, a side beam 2 is provided extending forward from the lower portion of the partition 1 separating the motor room and the vehicle compartment. In addition, the height of the side beam 2 gradually increases toward the rear end, and the rear end of the side beam 2 is embedded in the lower surface of the floor 6 of the vehicle compartment (refer to Figure 3 and Figure 5 ). The side beam 2 has a rectangular closed cross section that is long in the longitudinal direction. As will be discussed later, the horizontal width of the closed cross section varies along the length direction of the side beam.
[0022] A hood bracket 4 is provided extending forward from the upper portion of the bulkhead 1, more specifically, from the joint between the upper portion of the bulkhead 1 and the A-pillar 3. That is, the hood bracket 4 is provided extending forward parallel to the side beam 2 above the side beam 2. However, when viewed from above, the hood bracket 4 is located laterally outward of the side beam. The hood bracket 4 has a rectangular closed cross section that is longer in the transverse direction. However, the height of the hood bracket 4 gradually increases toward the lower portion of the A-pillar 3 (bulkhead 1), and the closed cross section of the hood bracket 4 becomes a longitudinally longer closed cross section at its rear portion.
[0023] A connecting member 5 is provided extending obliquely downward from the front end of the hood bracket 4. However, the connecting member 5 extends vertically near the end. That is, the hood bracket 4 and the connecting member 5 are continuously formed. As will be described in detail later, the top end of the connecting member 5 is joined to the side of the side beam 2, and the hood bracket 4 and the side beam 2 are connected by the connecting member 5. The connecting member 5 also basically has a laterally long rectangular closed cross-section like the hood bracket 4. However, as will be described in detail later, the closed cross-section of the vertical portion near the top end of the connecting member 5 is slightly different. That is, the hood bracket 4 and the connecting member 5 are arranged in a manner to surround the upper side of the front wheel on the outer side of the side beam 2.
[0024] In addition, if Figure 1 The double-dotted lines in the figure indicate that a protruding member 15 having a hat-shaped cross section is also connected from the front end of the hood bracket 4 and is continuous to the radiator core support top beam (not shown) supporting the radiator. The side beam 2, the hood bracket 4 and the connecting member 5 are formed by welding stamped steel plates, and have a closed cross section as described above. The side beam 2, the hood bracket 4 and the connecting member 5 are the main components for ensuring the rigidity of the vehicle body, and bear the collision load when the front of the vehicle collides. These components function as a loading path for transmitting the collision load. In addition, these components transmit the collision load when the collision load is large, and at the same time absorb the collision energy of the collision load by their own crushing.
[0025] A support tower 7 is also provided so that the rear portion 2c of the side beam 2 is connected to the hood support 4. An energy box 9 is installed at the front end of the side beam 2 via a plate member 8. A bumper reinforcement 10 is installed so that the left and right energy boxes 9 are connected. The energy box 9 is made to be easily crushed relative to the side beam 2. When the collision load is small, only the energy box 9 is crushed to suppress the deformation of the side beam 2. That is, when the collision load is small, repair can be performed by simply replacing the energy box 9 (and the bumper reinforcement 10).
[0026] like Figure 4 As shown in the bottom view of the side beam 2, the side beam 2 includes a front portion 2a, a transition portion 2b, and a rear portion 2c in order from the front thereof. As described above, the side beam 2 has a closed cross section, and therefore, the front portion 2a, the transition portion 2b, and the rear portion 2c also have closed cross sections. The front portion 2a is set in a range of a predetermined length from the front end of the side beam 2, and has a constant first horizontal width. The rear portion 2c is set at a position rearward of the front portion 2a, and has a second horizontal width smaller than the first horizontal width of the front portion 2a. The transition portion 2b is set between the front portion 2a and the rear portion 2c, and its horizontal width gradually changes from the first horizontal width to the second horizontal width.
[0027] The side beam 2 is formed by welding the inner plate 2i and the outer plate 2o at flanges formed at their upper and lower edges. Figure 4 The welded flange 2d is shown in FIG. The horizontal width of the transition portion 2b is gradually changed by gradually expanding the outer plate 2o toward the front and the outside. In addition, a mounting bracket 2e for a subframe for suspension installation is combined on the lower surface of the rear portion 2c, and a recessed portion 2f is also provided on the outer side surface of the rear portion 2c to avoid interference with the turned tire (see FIG. Figure 2 to Figure 5 ) An inclined surface 2g is formed on the outer side surface of the transition portion 2b, which faces laterally outward and rearward.
[0028] The vertically extending portion of the connecting member 5 is joined to the side beam 2 at the inclined surface 2g of the transition portion 2b. More specifically, the connecting member 5 is joined to the side beam 2 in a state where the surface of the connecting member 5 is in surface contact with the inclined surface 2g. Figure 4 As shown, the vertically extending portion of the connecting member 5 has a closed cross section formed by the horizontally long rectangular cross section expanding obliquely toward the inner rear. The inclined portion of the portion expanding toward the inner rear is in surface contact with the inclined surface 2g of the transition portion 2b.
[0029] Furthermore, in the present embodiment, the crash box 9 also has a closed cross section, and its closed cross section shape is the same as the closed cross section shape of the front portion 2a of the side member 2. Furthermore, the crash box 9 and the front portion 2a are connected via the plate member 8 without being deviated horizontally and vertically. Therefore, the collision load is efficiently transmitted from the crash box 9 to the front portion 2a of the side member 2 via the plate member 8.
[0030] like Figure 1 to Figure 3 As shown, at the joint between the side beam 2 and the connecting member 5 in the transition portion 2b, the side beam 2 is extended in the front-rear direction of the vehicle body, and the connecting member 5 is extended in the vertical direction. Figure 4 As shown, the end of the connection member 5 is not open downward, but is closed by attaching a bottom plate 5a.
[0031] In a small overlap collision, only one of the above-mentioned structures symmetrically constructed on the left and right sides of the front part of the vehicle body bears the collision load. Figure 4 As shown, the obstacle X moves relatively backward with respect to the vehicle body, and the collision load is first input into the bumper reinforcement 10 and the energy absorbing box 9. The energy absorbing box 9 is crushed, and the collision load is transmitted to the front portion 2a of the side member 2. Moreover, the collision load is transmitted to the loading path to the rear portion 2c and the loading path to the connecting member 5 at the transition portion 2b.
[0032] That is, the collision load can be effectively resisted by using the loading path of the side beam 2 and the loading path of the connecting member 5 and the hood bracket 4. In this embodiment, the collision load is reliably borne by the front portion 2a of the side beam 2, and then branches into two loading paths at the transition portion 2b. Therefore, the collision load can be reliably resisted by using the two loading paths. The collision load at the front of the vehicle body can be effectively resisted, and the absorption efficiency of the collision energy at the front of the vehicle body can be improved, so that the reinforcement of the vehicle compartment can also be reduced.
[0033] Regarding the branching of the loading path in the transition portion 2b, in the loading path of the side beam 2, the collision load is reliably transmitted from the front portion 2a, the transition portion 2b, and the rear portion 2c, whose horizontal width gradually decreases. In the case where the side beam 2 is buckled due to the collision load, it is horizontally buckled because it is a longitudinally long closed section. On the other hand, in the loading path of the connecting member 5 and the hood bracket 4, the collision load is reliably transmitted from the transition portion 2b to the connecting member 5 via the inclined surface 2g facing laterally outward and toward the rear. In the case where the connecting member 5 and the hood bracket 4 are buckled due to the collision load, they are vertically buckled because they are a transversely long closed section.
[0034] In the transition portion 2b, the side beam 2 is extended in the front-to-back direction of the vehicle body, and the connecting member 5 is extended in the vertical direction. The side beam 2 extending in the front-to-back direction can efficiently bear the collision load by utilizing its linear loading path. The connecting member 5 extending in the vertical direction can increase the contact area with the inclined surface 2g of the transition portion 2b and improve the transmission efficiency of the collision load. In addition, by extending the connecting member 5 in the vertical direction, the front-to-back length of the connecting member 5 can be shortened, and the front overhang can be prevented from becoming longer.
[0035] Regarding the transmission of the impact load from the transition portion 2b to the top end of the connecting member 5 extending in the vertical direction, if the closed cross section of the connecting member 5 is crushed, the transmission efficiency is reduced. The above-mentioned bottom plate 5a prevents the closed cross section of the connecting member 5 from being crushed. In addition, when the impact load is large and the vehicle body structure in front of the transition portion 2b is completely crushed, in addition to the side beam 2 (transition portion 2b and rear portion 2c), the vertical extension portion of the connecting member 5 can also be used to efficiently bear the impact load. In this case, the two loading paths continue to be effective.
[0036] The above advantages can be obtained not only in a small overlap collision but also in a full overlap collision in which the impact load can be borne by the above structures symmetrically constructed on both sides of the vehicle body. However, according to the above structure, only one side of the left and right sides of the vehicle body can effectively resist the collision load by using two load paths in a small overlap collision.
[0037] Next, refer to Figure 5 , and further features of the vehicle body structure of the present embodiment are described. In the present embodiment, in addition to the overhanging joist 11, a gusset plate 12 is provided at the joint between the bulkhead 1 of the side member 2 and the floor 6. The overhanging joist 11 is joined to the lower surface of the floor 6 and connects the rear end of the side member 2 to the side rail 13. The load path of the side member 2 is extended from the overhanging joist 11 to the side rail 13. The gusset plate 12 is joined to the lower surface of the floor 6 on the side opposite to the side rail 13 at the rear end of the side member 2 and joins the rear end of the side member 2 to the floor 6.
[0038] As described above, the vehicle of this embodiment is an HEV, and a relatively small center tunnel 14 is formed in the center of the front end of the floor 6. An exhaust pipe extending from the internal combustion engine in the motor room and a cable that electrically connects the motor generator in the motor room and the battery pack (not shown) mounted under the floor 6 are arranged in the center tunnel 14. A gusset 12 is joined between the center tunnel 14 and the rear end of the side member 2.
[0039] The overhanging joist 11 has a substantially right-angled trapezoidal shape when viewed from above, and forms a closed cross section together with the floor 6 by being joined to the lower surface of the floor 6. The rear edge of the overhanging joist 11 is joined to the lower surface of the floor 6. The inclined front edge of the overhanging joist 11 rises upward and is joined to the lower edge of the partition 1. The inner end of the overhanging joist 11 is joined to the bottom surface and the outer side surface of the rear end portion of the side beam 2. The outer end of the overhanging joist 11 is joined to the inner side surface of the topmost portion of the side edge beam 13.
[0040] The gusset plate 12 also has a substantially right-angled trapezoidal shape substantially symmetrical to the shape of the overhanging joist 11 when viewed from below, and forms a closed cross section together with the floor 6 by being joined to the lower surface of the floor 6. The rear edge of the gusset plate 12 is joined to the lower surface of the floor 6. The inclined front edge of the gusset plate 12 is joined to the lower edge of the bulkhead 1 and the inner side surface of the side member 2. The inner end of the gusset plate 12 is joined to the floor 6 along the center channel 14. The outer end of the gusset plate 12 is joined to the lower surface of the side member 2.
[0041] The rear end of the side member 2 is firmly joined to the vehicle body from both sides by the overhanging joist 11 and the gusset 12. Therefore, it is not necessary to extend the side member 2 on the lower surface of the floor 6, and the lower surface of the floor 6 can be made substantially flat. As a result, it is easy to mount the battery pack under the floor 6, and the volume of the battery pack will not be reduced. In addition, the lower surface of the floor 6 is reinforced by the overhanging joist 11 and the gusset 12, so it is not necessary to reinforce the interior of the vehicle or the reinforcement of the interior of the vehicle is minimized, and the volume of the vehicle will not be reduced.
[0042] The collision load transmitted by the side member 2 is further transmitted to the side member 13 by the overhanging joist 11, and is also transmitted to the floor 6 by the overhanging joist 11 and the gusset plate 12. Therefore, the collision load can be effectively resisted. In addition, when the collision load is transmitted to the floor 6, the front edges of the overhanging joist 11 and the gusset plate 12 are arranged in a manner that widens toward the rear, so that the collision load can be appropriately dispersed. In addition, the rear end of the side member 2 is reliably supported by the overhanging joist 11 and the gusset plate 12, so that the front part of the side member 2 can be reliably crushed by the impact load and the collision energy can be reliably absorbed.
[0043] Next, refer to Figure 6 , and further features of the vehicle body structure of this embodiment are described. In a small overlap collision, as described above, only one of the above-mentioned structures symmetrically constructed to the left and right sides of the front part of the vehicle body bears the collision load. In the case of a large collision load, there is a case where the collision energy cannot be completely absorbed by the front part of the vehicle body alone, and the collision load is also input to the front end of the side beam 13. The collision load via the above-mentioned overhanging joist 11 and the load generated by contact with the front wheel that has moved relatively backward relative to the vehicle body due to the collision are input to the front end of the side beam 13.
[0044] When the collision load is input to the front end of the side beam 13, a load that causes the side beam 13 to bend outward acts on the side beam 13. That is, a load that causes the side beam 13 to be pulled outward from the floor 6 acts. In this embodiment, a structure that can effectively resist this load to the side is also constructed. Figure 6 yes Figure 5 The VI-VI line section view in the figure. Figure 6 As shown, the floor panel 6 is welded (spot welded or line welded) to the upper surface and the inner side surface of the side beam 13 . Figure 6 The position indicated by * in the figure is the welding position. The welded portion where the steel plates are in surface contact with each other is also affected by the grade of the steel plates, but the shear strength (strength in the direction within the joint surface) is higher than the peel strength (strength in the direction perpendicular to the joint surface).
[0045] Therefore, in this embodiment, the floor panel 6 is welded not only to the side surface 13b of the side beam 13, but also to the upper surface 13a. Figure 6 In the cross-sectional view shown, the floor panel 6 is welded to the upper surface 13a of the side beam 13 at one location and to the side surface 13b of the side beam 13 at two locations. The upper surface 13a of the side beam 13 is substantially horizontal, and the load that pulls the side beam 13 outward from the floor panel 6 acts as a shear load on the welded portion on the surface of the floor panel 6 joined to the upper surface 13a. On the other hand, the load that pulls the side beam 13 outward from the floor panel 6 acts as a peeling load on the welded portion on the surface of the floor panel 6 joined to the side surface 13b of the side beam 13.
[0046] In this way, by welding the floor panel 6 to both the upper surface 13a and the side surface 13b of the side member 13, the load that pulls the side member 13 outward can be effectively resisted. That is, the joint between the floor panel 6 and the side member 13 can effectively cope with both shearing and peeling. In addition, the first surface 6a of the floor panel 6 welded to the upper surface 13a and the second surface 6b of the floor panel 6 welded to the side surface 13b serve as corner reinforcement members to reinforce the side member 13, so the rigidity of the vehicle body can also be improved.
[0047] According to the vehicle body structure of the present invention, the vehicle body structure includes the above-mentioned side beam 2 having a closed cross section, the hood bracket 4, and the connecting member 5. The side beam 2 includes: a front portion 2a having a constant first horizontal width; a rear portion 2c having a second horizontal width smaller than the first horizontal width; and a transition portion 2b provided between the front portion 2a and the rear portion 2c, the horizontal width of which gradually changes from the first horizontal width to the second horizontal width. The front end of the connecting member 5 is joined to the side beam 2 at an inclined surface 2g facing laterally outward and rearward of the transition portion 2b.
[0048] Therefore, the collision load (especially in the case of a small overlap collision) is reliably transmitted to both the loading path to the rear portion 2c of the side member 2 and the loading path of the connecting member 5 and the hood bracket 4 at the transition portion 2b via the front portion 2a of the side member 2. The loading path is branched after passing through the front portion 2a, so that it is not transmitted to only one of the loading path to the rear portion 2c of the side member 2 and the loading path of the connecting member 5 and the hood bracket 4. Therefore, the collision load (especially in the case of a small overlap collision) can be appropriately branched, and the collision load can be effectively counteracted by using two loading paths.
[0049] According to the vehicle body structure of the present invention, at the joint between the side beam 2 and the connecting member 5 in the transition portion 2b, the side beam 2 is extended in the front-to-back direction of the vehicle body, and the connecting member 5 is extended in the vertical direction. The side beam 2 extending in the front-to-back direction can efficiently bear the collision load by utilizing its linear loading path. The connecting member 5 extending in the vertical direction increases the contact area with the inclined surface 2g of the transition portion 2b, thereby improving the transmission efficiency of the collision load. In addition, by extending the connecting member 5 in the vertical direction, the front-to-back length of the connecting member 5 can be shortened, and the front overhang can be prevented from becoming longer.
[0050] In addition, the vehicle body structure of the present invention further includes the above-mentioned overhanging joist 11 and gusset plate 12. Therefore, the rear end of the side member 2 is firmly joined to the vehicle body from both sides by the overhanging joist 11 and the gusset plate 12. It is not necessary to extend the side member 2 on the lower surface of the floor 6, and the lower surface of the floor 6 can be made substantially flat. In addition, since the lower surface of the floor 6 is reinforced by the overhanging joist 11 and the gusset plate 12, it is not necessary to reinforce the interior of the vehicle or the reinforcement of the interior of the vehicle is minimized, and the volume of the vehicle does not decrease.
[0051] Furthermore, according to the vehicle body structure of the present invention, the floor panel 6 is welded to both the upper surface 13a and the side surface 13b of the side member 13. Therefore, the load that pulls the side member 13 laterally outward (especially in a small overlap collision) can be effectively resisted. In addition, the joint between the floor panel 6 and the side member 13 serves as a corner reinforcement member to reinforce the side member 13, thereby also improving the vehicle body rigidity.
[0052] Description of Reference Numerals
[0053] 1. Bulkhead; 2. Side beam; 2a. Front portion (of side beam 2); 2b. Transition portion (of side beam 2); 2c. Rear portion (of side beam 2); 2g. Inclined surface (of transition portion 2b); 3. A-pillar; 4. Hood support; 5. Connecting member; 6. Floor; 11. Extended joist; 12. Gusset plate; 13. Side beam; 13a. Upper surface (of side beam 13); 13b. Side surface (of side beam 13).
Claims
1. A vehicle body structure comprising: a side member extending forward from a lower portion of a bulkhead and having a closed cross section, the bulkhead separating a front portion of the vehicle body from a passenger compartment; an engine hood support extending forward from a junction between an upper portion of the bulkhead and the A-pillar and having a closed cross section; as well as A connecting member extending downward from the front end of the engine hood support and having a closed cross section, The side beam comprises: a front portion, which is provided in a range of a predetermined length from a front end of the side beam and has a constant first horizontal width; and a rear portion, which is provided at a position rearward of the front portion and has a second horizontal width smaller than the first horizontal width; and a transition portion, which is disposed between the front portion and the rear portion, and whose horizontal width gradually changes from the first horizontal width to the second horizontal width, An inclined surface facing outward and rearward is formed on the outer side surface of the transition portion. The front end of the connecting member is engaged with the side beam at the inclined surface of the transition portion.
2. The vehicle body structure according to claim 1, wherein: At a joint portion between the side beam and the connecting member in the transition portion, the side beam is extended in a front-rear direction of the vehicle body, and the connecting member is extended in a vertical direction.
3. The vehicle body structure according to claim 1 or 2, wherein: The vehicle body structure further comprises: an overhanging joist that engages the lower surface of the floor of the compartment and connects the rear end of the side beam to the side rail; and A gusset is joined to a lower surface of the floor panel at a side of the rear end portion of the side member opposite to the side rail to join the rear end portion to the floor panel.
4. The vehicle body structure according to claim 3, wherein: The floor panel is welded to both the upper surface and the side surface of the side beam.