JP3724044B2 - Automobile front structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a front structure of an automobile, and more particularly, to a front structure of an automobile that solves a problem that occurs when an engine moves backward toward a vehicle compartment during a frontal collision.
[0002]
[Prior art]
In general, as one form of an automobile body, a pair of left and right front side frames extending in the front-rear direction is provided at the front portion of the car body, and the front side frames are connected to each other so that two cross members are predetermined in the front-rear direction. Some have a configuration in which an engine is disposed above and between the two cross members.
[0003]
Further, as another form of the automobile body, a pair of left and right front side frames extending in the front-rear direction at the front portion of the vehicle body are connected to each other, and one cross member is attached. A pair of left and right front and rear members each having one end joined to the front side frame and the other end joined to the front side frame, and an engine is disposed above the cross member and the front and rear members. Some have a different configuration.
[0004]
Further, as disclosed in, for example, Japanese Utility Model Laid-Open No. 4-98615, at the time of a frontal collision, the power plant including the engine is dropped down to secure a crushing space for the front body structure member, thereby colliding energy. There is also known one that absorbs.
[0005]
[Problems to be solved by the invention]
By the way, in recent years, there is a tendency for the front overhang of the vehicle body to be shortened due to a demand to make the interior space of the automobile as large as possible, and therefore it is not possible to secure a crushable zone sufficient to absorb the impact at the time of frontal collision. Therefore, the engine is retracted, and the front side frame portion between the two cross members or the front side frame portion facing the front and rear members is crushed and deformed to absorb the collision load.
[0006]
However, as described above, the engine is retracted at the time of a frontal collision, and accordingly, the front side frame part between the two cross members or the front side frame part facing the front and rear members is crushed and deformed to absorb the collision load. In the configuration, when the reverse amount of the engine becomes excessive, the front lower portion of the steering shaft is pushed backward by the engine and the steering wheel connected to the steering shaft moves backward toward the occupant. Further, there has been room for further improvement in terms of safety for the passengers by displacing so as to rotate upward.
[0007]
In view of the circumstances described above, the present invention connects the left and right front side frames, two cross members are attached at a predetermined interval in the front-rear direction, and the engine is disposed above the two cross members. In the front structure of the installed vehicle or between the left and right front side frames, one cross member is attached, and one end is joined to the left and right ends of the cross member. In the front structure of an automobile provided with a pair of left and right front and rear members that extend forward or rearward and whose other ends are joined to the front side frame, respectively, and the engine is disposed above the cross member and the front and rear members, The purpose is to solve the problem.
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, the pair of left and right front side frames are connected to each other , and two cross members are attached at a predetermined interval in the front-rear direction. In the front structure of an automobile in which a front wheel suspension arm is swingably attached to the both cross members via bushes on both cross members, the reverse movement of the engine during a frontal collision is suppressed. On the other hand, the front side frame portion between both cross members is crushed and deformed to absorb the impact load.
[0009]
Specifically, the engine is attached to the front side frame portion between the two cross members via the engine mount bracket, and when the front collision occurs, the engine mount bracket and the front side frame portion are joined and the cross member and the front side frame are connected. What is necessary is just to comprise so that coupling | bonding can be cancelled | released.
[0010]
Further, according to the present invention, as described in claim 2 , the pair of left and right front side frames are connected to each other, and one cross member is attached, and one end is respectively attached to the left and right end portions of the cross member. are joined extends vehicle forward or backward, the other end respectively bonded pair of longitudinal members to the front side frame is provided, the engine is disposed above the cross member and the longitudinal member, the said cross member In a front structure of an automobile in which a front wheel suspension arm is mounted so as to be swingable in a vertical direction via a bush , the front facing the front and rear members is suppressed while suppressing the reverse of the engine due to an impact load at the time of a frontal collision. The side frame is crushed and deformed to absorb the impact load. That.
[0011]
Specifically, the engine is attached to the front side frame portion facing the front and rear members via the engine mount bracket, and when the front collision occurs, the engine mount bracket and the front side frame portion are joined and the front and rear members or the cross member and the front What is necessary is just to comprise so that coupling | bonding with a side frame can be cancelled | released.
[0012]
【The invention's effect】
According to the present invention, at the time of a frontal collision, the front side frame portion between the cross members or the front and rear members are suppressed while suppressing the backward movement of the engine by releasing the coupling between the engine mount bracket and the front side frame portion. Even when the opposing front side frame portions are crushed and deformed to absorb the impact load, the steering wheel can be prevented from moving backward or displaced, and further safety of the occupant during a frontal collision can be ensured.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, reference and embodiments of a vehicle lower structure according to the present invention will be described with reference to the drawings.
[0014]
1 is a bottom view schematically showing a front body structure of a four-wheel drive vehicle based on a rear-wheel drive vehicle to which the reference and embodiments of the present invention are applied, and FIG. 2 is a side view of the same. 3 is a front view of the same.
[0015]
In the figure, a pair of left and right front side frames 1L, 1R extending in the front-rear direction is provided at the front portion of the vehicle body 10, and the two cross members 2, 3 are connected by connecting the front side frames 1L, 1R. Are mounted at a predetermined interval in the front-rear direction, and an engine 5 is disposed above the cross members 2 and 3. The engine 5 is connected to both crosses via the left and right engine mount brackets 4 and 4. It is attached to the front side frame portion between the members 2 and 3. Further, the base ends of the lower arms 6L and 6R of the front wheel suspension device are attached to both the cross members 2 and 3 through a bush so as to be swingable in the vertical direction.
[0016]
A transmission mechanism 7 is attached to the rear of the engine 5, and a rear wheel drive propeller shaft (not shown) is led rearward from the rear end of the transmission mechanism 7, and laterally from the rear end of the transmission mechanism 7. The front end of a propeller shaft 9 for driving the front wheels that is led forward from a transfer mechanism 8 that protrudes toward the front is connected to a front wheel differential gear mechanism 11, and a front wheel drive shaft 12 </ b> L that is led left and right from the front wheel differential gear mechanism 11. The front wheels 13L and 13R are driven by 12R.
[0017]
Three joints J1, J2, and J3 are interposed in the steering shaft 15 that connects the steering wheel SW and the front wheel steering mechanism (not shown).
[0018]
4 is a perspective view showing a first reference embodiment of the present invention, FIG. 5 is an enlarged perspective view of the main part of FIG. 4, and FIGS. 6 and 7 are VI-VI line and VII-VII of FIG. It is sectional drawing along a line.
[0019]
The steering shaft 15 is divided into four parts in the axial direction by three joints J1, J2, J3 from the rear upper side to the front lower side, and the shaft part between the first joint J1 and the second joint J2 15a passes through the dash panel 14 that partitions the engine compartment and the vehicle compartment, and is rotatably supported by a support bracket 22 provided on the dash panel 14, and is provided between the second joint J2 and the third joint J3. The shaft portion 15 b is supported by the vehicle body via the support bracket 16.
[0020]
As shown in FIG. 7, the support bracket 16 includes a bearing 17 and a cylindrical shaft support portion 18 that rotatably supports the shaft portion 15b. The support bracket 16 is provided integrally with the shaft support portion 18 and fixed to the vehicle body. The fixing portion 19 is fixed to a welded portion between the front side frame 1R and the suspension tower 20 on the right side (in the case of a right-hand drive vehicle) including the outer member 1a and the inner member 1b. Further, a pawl member 21 for preventing the shaft portion 15b from moving backward is fixed to the shaft portion 15b adjacent to the front of the shaft support portion 18 of the support bracket 16.
[0021]
In the present reference, via a steering shaft portion 15b is welded portion of the front side frame 1R and suspension tower 20, i.e., strength strong, the support bracket 16 to a relatively small portion of the retreating during frontal collision And a third joint J3, which is a structural weak portion, is provided at the front lower side of the steering shaft portion 15b. Further, the support bracket 16 and the pawl member 21 prevent the rearward upward movement. Therefore, even when the engine 5 moves backward during a frontal collision, the backward movement of the steering wheel SW is suppressed.
[0022]
FIG. 8 is a perspective view showing a second reference embodiment of the present invention. FIG. 9 is a schematic plan view, FIG. 9 shows a state before a frontal collision, and FIG. 9B shows a state after a frontal collision. FIG. 10 is a sectional view taken along line XX in FIG.
[0023]
In this reference embodiment, as shown in FIG. 9 (a), the dash panel 14, a right side dash panel portion 14a and the central dash panel portion 14b, which is divided into three parts in the vehicle width direction and left dash panel portion 14c The shaft portion 15a between the first joint J1 and the second joint J2 passes through the right dash panel portion 14a (in the case of a right-hand drive vehicle) and is rotated by a support bracket 22 provided on the dash panel portion 14a. It is supported freely.
[0024]
As shown in FIG. 10, the support bracket 22 includes a bearing 23 and rotatably supports the shaft portion 15a. The shaft portion 15a has a pawl member 24 for preventing the shaft portion 15a from moving backward. It is fixed adjacent to the front of the support bracket 22.
[0025]
In the present reference, to dash panel 14 is divided into three parts in the vehicle width direction, at the time of frontal collision, as shown in FIG. 9 (b), with the retraction of the engine 5, the central dash panel portion 14b Only is configured to be separated from the dash panel portions 14b and 14c on both sides and retract. Further, since the second joint J2, which is a structural weak portion, is provided at the front lower side of the steering shaft portion 15a, the steering shaft portion 15a is interposed via the support bracket 22 even when the engine 5 moves backward during a frontal collision. The right dash panel portion 14a that supports the steering wheel SW does not move backward, thereby preventing the steering wheel SW from moving backward.
[0026]
Figure 11 is a side view schematically showing a third reference embodiment of the present invention, for example, the intermediate portion of the steering shaft portion 15b is divided into a shaft portion 15c and the shaft portion 15d, both shaft portions 15c, 15d of The axes are shifted from each other, and rotation transmission between the shaft portions 15c and 15d is performed by meshing serrations S provided at the ends of the shaft portions 15c and 15d.
[0027]
With such a structure, when the front lower shaft portion 15d moves rearward during a frontal collision, the shaft portions 15c and 15d can be easily separated to prevent displacement of the steering wheel SW.
[0028]
FIG. 12 is a side view schematically showing a fourth reference embodiment of the present invention. For example, a notch 25 is formed on the outer peripheral surface of the steering shaft portion 15b, and this portion is used as a fragile portion. Thus, this portion is configured to be easily deformed to prevent displacement of the steering wheel SW.
[0029]
The above reference example is a case where the steering shaft 15 itself or the support portion of the steering shaft 15 is provided with a countermeasure so as to suppress the backward movement or displacement of the steering wheel SW. This is a case in which the reverse or displacement of the steering wheel SW accompanying the reverse of the engine 5 is suppressed by suppressing the excessive reverse of 5.
[0030]
FIG. 13 is an exploded perspective view conceptually showing the first embodiment of the present invention. In the front side frame 1R on the right side of the vehicle body, the front and rear cross members 2, 3 and the engine mount bracket 4 extending in the vehicle width direction are shown. Shows a state where is attached by bolting. FIG. 14 is an enlarged plan view of the engine mount bracket 4.
[0031]
In the present embodiment, as shown in FIG. 14, a groove 4a extending in the vehicle width direction is formed in a fastening portion of the engine mount bracket 4 to the front side frame 1R, and two bolt holes provided at the front and rear sides. 4b and 4b are notched so as to open to the front edge of the engine mount bracket 4 and the rear edge of the groove 4a. The engine mount bracket 4 attached to the other front side frame 1L has the same configuration. In FIG. 13, 1a is a mounting bolt and 1b is a tool insertion hole.
[0032]
If the engine mount bracket 4 having such a configuration is used, the engine mount brackets 4 and 4 are uncoupled from the front side frames 1L and 1R when the engine 5 moves backward due to an impact at the time of a frontal collision. Falls down, and excessive retreat of the engine 5 is suppressed, and the portion between the cross members 2 and 3 of the front side frames 1L and 1R is used as a crushing space to effectively absorb the impact load at the time of a frontal collision. Can do.
[0033]
In this case, since the cross members 2 and 3 exist below the engine 5, the engine 5 can be completely operated only by releasing the coupling between the engine mount brackets 4 and 4 and the front side frames 1L and 1R. Does not fall. Therefore, as schematically shown in FIG. 15 (a), the rubber member 30 is fixed to the fastening portions of the cross members 2 and 3 of the front side frames 1L and 1R, and the both ends of the cross members 2 and 3 are A notch 31 that opens to the front side of the vehicle body into which the rubber member 30 is fitted is formed.
[0034]
If the fastening portions of the cross members 2 and 3 with respect to the front side frames 1L and 1R are configured as described above, the rubber member 30 is bent as the cross members 2 and 3 are retracted due to an impact load at the time of a frontal collision. As shown in FIG. 15B, since the cross members 2 and 3 can be detached from the front side frames 1L and 1R, the engine 5 can be dropped downward.
[0035]
In the first to fourth reference embodiments and the first embodiment of the present invention described above, the left and right front side frames 1L and 1R are connected to each other so that the two cross members 2 and 3 are connected. This is a case where the engine 5 is mounted at a predetermined interval in the front-rear direction and between the cross members 2 and 3, but the present invention is also applicable to an automobile having another frame structure. Can do.
[0036]
That is, as shown in FIG. 16, a pair of left and right front side frames 1L and 1R are connected to each other, and one cross member 2 is attached, and one end is joined to the left and right ends of the cross member 2, respectively. Thus, a pair of left and right front and rear members 35, 35 extending rearward of the vehicle body and joined at the other end to the front side frames 1L, 1R are provided, and the engine 5 is disposed above the cross member 2 and the front and rear members 35, 35. It is obvious that the first to fourth reference embodiments can be similarly applied to the configuration to be performed. In the configuration shown in FIG. 16, although not shown, suspension arms are attached to the front and rear ends of the front and rear members 35, 35.
[0037]
In the first embodiment shown in FIG. 13, the engine mount brackets 4 and 4 are attached to the front side frame portion between the front and rear cross members 2 and 3, but in the configuration shown in FIG. Engine mount brackets 4 and 4 as shown in FIG. 14 are attached to the front side frame portions facing the front and rear members 35 and 35, respectively. Accordingly, when the engine 5 moves backward due to the impact of the frontal collision, the coupling between the engine mount brackets 4 and 4 and the front side frames 1L and 1R is released, so the engine 5 falls off downward, and the engine 5 is excessively moved backward. It is suppressed.
[0038]
Further, the attachment portions 35a, 35a to the front side frames 1L, 1R formed at the rear end portions of the front and rear members 35, 35 and the fastening portions with respect to the front side frames 1L, 1R at both ends of the cross member 2 are shown in FIG. The engine 5 can be dropped completely downward by configuring so that the coupling with the front side frames 1L and 1R is released by an impact load at the time of a frontal collision.
[0039]
In the frame configuration shown in FIG. 16, the front and rear members 35, 35 extend rearward from the left and right ends of the cross member 2 and are joined to the front side frames 1L, 1R. One cross member may be provided at a position corresponding to the rear cross member 3, and front and rear members that extend forward from the left and right ends of the cross member and are joined to the front side frames 1L and 1R may be provided. In that case, the rear end portions of the front and rear members 35, 35 are joined to the cross member, and measures may be taken on the joined portions in the same manner as described above.
[Brief description of the drawings]
FIG. 1 is a bottom view schematically showing a front structure of an automobile to which the present invention is applied. FIG. 2 is a side view. FIG. 3 is a front view. FIG. 4 is a first reference embodiment of the present invention. FIG. 5 is an enlarged perspective view of the main part of FIG. 4. FIG. 6 is a sectional view taken along line VI-VI in FIG. 5. FIG. 7 is a sectional view taken along line VII-VII in FIG. FIG. 8 is a perspective view showing a second reference embodiment of the present invention. FIG. 9 is a schematic plan view of the same. FIG. 10 is a cross-sectional view taken along line XX of FIG. conceptually showing disassembled first embodiment of the fourth side view schematically showing the configuration of a reference of a side view schematically showing the embodiment 12 of the present invention in reference [13] the present invention FIG. 14 is an enlarged plan view of the engine mount bracket of FIG. 13. FIG. 15 is a plan view schematically showing the structure of the fastening portion of the cross member with respect to the front side frame. FIG. 16 is an exploded perspective view showing another frame structure to which the present invention is applied.
1L, 1R Front side frame 2, 3 Cross member 4 Engine mount bracket 5 Engine 14 Dash panel 14a, 14b, 14c Dash panel portion 15 Steering shaft 15a, 15b Steering shaft portion 16, 22 Support bracket 17, 23 Bearing 21, 24 Pawl Member 30 Rubber member 35 Front and rear members

Claims (2)

A pair of left and right front side frames extending in the front-rear direction at the front of the vehicle body are connected to each other, two cross members are attached at a predetermined interval in the front-rear direction, and the engine is arranged above the cross members. In the front structure of an automobile in which a front wheel suspension arm is attached to both the cross members via a bush so as to be swingable in the vertical direction .
The engine is supported by the engine via brackets so that the front side frame portion between the two cross members is crushed and deformed to absorb the impact load while suppressing the retreat of the engine due to the impact load at the time of a frontal collision. It is attached to the front side frame part between the cross members, and is configured so that the coupling between the engine mount bracket and the front side frame part and the coupling between the cross member and the front side frame can be released at the time of a frontal collision. front structure of a motor vehicle, characterized by comprising. A pair of left and right front side frames extending in the front-rear direction at the front portion of the vehicle body are connected to each other, and one cross member is attached. One end is joined to each of the left and right end portions of the cross member, A pair of left and right front and rear members that extend rearward and whose other ends are respectively joined to the front side frame are provided, and an engine is disposed above the cross member and the front and rear members , and the cross member includes a front wheel suspension arm. In the front structure of an automobile, which is attached so as to be swingable in the vertical direction via a bush ,
The engine is connected to the front and rear through the engine mount bracket so that the front side frame portion facing the front and rear members is crushed and deformed to absorb the impact load while suppressing the retreat of the engine due to the impact load at the time of a frontal collision. It is attached to the front side frame part that faces the member, so that the coupling between the engine mount bracket and the front side frame part and the coupling between the front and rear members or the cross member and the front side frame can be released at the time of a frontal collision. 1. A front structure of an automobile characterized by being configured as follows .

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