JPH0732345Y2 - Front body structure of automobile - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) The present invention relates to a front body structure of an automobile, more specifically, a front portion of an automobile in which a front body around a suspension tower and a vehicle compartment are three-dimensionally connected and reinforced. Regarding the body structure.

(Prior Art) Conventionally, in a front vehicle body structure of an automobile, a front side frame is relatively large and heavy in order to obtain strength and rigidity in which vibration or squeaking does not occur in the vehicle body even when vibration is input from a suspension. Things were being used.
An example of a vehicle body structure for reducing the weight of such a front body structure is a vehicle body structure described in Japanese Utility Model Laid-Open No. 62-36876.

This is a straight extension that is located at both left and right sides of the vehicle body floor panel and that extends in the front-rear direction, and hangs downward from the rear side position of this straight extension and bends outward in the vehicle width direction. A front side member composed of a downwardly curved portion connected to the front end, and an inner corner formed by the front side member and the dash panel are directly extended to the inner corner to reinforce the inner corner. A gusset member is fixedly provided on the rear end of the portion and the dash panel. And with such a configuration,
The load applied to the front side member in the front-rear direction is distributed to the gusset member in addition to the downward bending portion, and the bending moment acting on the front side member is absorbed by the gusset member.

(Problems to be solved by the invention) By the way, an uncomfortable vibration may occur in a high speed range exceeding 100 km / h due to an imbalance of wheel weight distribution, roundness, and the like. This is because the vibration from the suspension causes the vehicle body to bend, which is referred to as double-joint bending. Therefore, in order to reduce such bending of the vehicle body, it is necessary to improve the bending rigidity of the vehicle body with respect to the above-mentioned two-node bending and at the same time improve the mounting rigidity of the suspension tower. For that purpose, it is desired to three-dimensionally connect and reinforce the front body structure around the engine room and the cabin side in relation to the suspension tower.
However, since the gusset member in the above-described conventional structure does not contribute to the improvement of the mounting rigidity of the suspension tower described above and also increases the bending rigidity of the front vehicle body mainly in the left-right direction, It is not possible to effectively improve the bending rigidity with respect to knot bending, and it is not possible to effectively reduce the vehicle body vibration caused by the vibration from the suspension.

The present invention has been made in consideration of such circumstances, and the front body structure is three-dimensionally coupled and reinforced with the suspension tower to effectively reduce the vehicle body vibration caused by the vibration from the suspension. Especially.

(Means for Solving the Problem) In order to achieve the above object, the invention described in the scope of utility model registration claims is such that a suspension tower is provided on each of the wheel aprons forming the left and right side walls of the engine room, and A dash panel that is connected to the rear position of the apron and separates the engine room from the vehicle compartment is arranged so as to extend in the left-right direction, and the front side frame extends in the front-rear direction at the lower position inside the left-right direction of each suspension tower. It is assumed that the front vehicle body structure is arranged as described above. In this structure, a plate-shaped reinforcing member that extends in a vertical range from the front side frame to an upper position of the engine room and is bent to connect the suspension towers and the dash panel to each other, and the reinforcing member. It is laid in a space surrounded by the lower peripheral portion of the member, the front side frame and the dash panel, one side edge is on the lower peripheral portion of the reinforcing member, the other side edge is on the front side frame, and the rear edge is on the dash. And a bottom plate joined to each panel. One end of the reinforcing member is joined to the upper end of the suspension tower, the lower end of the intermediate portion extending inward in the left-right direction is joined to the front side frame, and the other end is extended forward from the intermediate portion. The dash panel and the tunnel forming portion located below the dash panel are joined together.

(Operation) A plate-shaped reinforcing member extends in the vertical range from the front side frame to the upper position of the engine room, and is arranged so as to be bent so as to connect the suspension tower and the dash panel to each other, and the bottom plate is bent as described above. Since it is provided so as to be joined to the lower peripheral portion of the reinforcing member, the front side frame, and the dash panel, the reinforcing member, the wheel apron provided with the suspension tower, and the dash panel are viewed in a plan view. A box-shaped closed section is formed, and the bottom surface of the box-shaped closed section is closed by the bottom plate between the front side frame and the dash panel to form a three-dimensional structure. As a result, the rigidity of the plate-shaped reinforcing member itself is improved, and the front body and the vehicle compartment are three-dimensionally coupled and reinforced by the reinforcing member having the increased rigidity.

Since one end of the reinforcing member is joined to the upper end of the suspension tower and the middle portion is joined to the front side frame, it serves as a suspension spring or damper support portion, and the vibration load from the suspension is The upper end of the suspension tower, which serves as an input point, is supported not only by the wheel apron but also by the front side frame through the reinforcing member, so that the mounting rigidity of the suspension tower is increased. Therefore, the displacement of the upper end portion of the suspension tower, which is the largest displacement due to the vibration load, is restricted, and the inward leaning phenomenon of the upper end portion of the suspension tower inward in the left-right direction is reliably prevented.

In addition, the other end of the reinforcing member is also joined to the dash panel and the tunnel forming portion below the dash panel, and is connected vertically from the tunnel forming portion position of the dash panel to the engine room upper position, and is reinforced as described above. Since the lower peripheral portion of the member is connected to the dash panel and the front side frame via the bottom plate, the bending rigidity of the front vehicle body is improved, and the strength against the two-joint bending that tends to occur at high speed becomes large.

By improving the mounting rigidity of the suspension tower and the bending rigidity of the front vehicle body as described above, the propagation of vibrations input from the suspension tower is effectively suppressed / reduced, and vehicle vibrations that tend to occur at high speeds are particularly effective. Is reduced to.

Embodiment An embodiment of the present invention will be described in detail below with reference to the drawings.

1 and 2 show an embodiment of the present invention. In the front body structure, a suspension tower 3 is provided on a wheel apron 2 that forms a side wall of the engine room 1, and a dash panel 5 that separates the engine room 1 and the vehicle room 4 from each other.
Is provided at a rear position of the engine room 1 so as to extend in the left-right direction so as to connect the left and right wheel aprons 2, 2 to each other. The suspension tower 3 is a suspension dash reinforcement 6 as a reinforcing member.
Is connected to the dash panel 5 by.

The suspension tower 3 is provided to support a spring that supports a front wheel, and is formed so as to surround the spring by a substantially cylindrical suspension housing 7 whose outer lower half is cut out in an arc shape. As shown in FIGS. 2 and 3, a substantially U-shaped suspension housing lower 8 is provided below the suspension housing 7, and an outer end portion of the suspension apron 2 has a wheel apron 2 via a gusset member or the like (not shown). And the inner end thereof is joined to the side frame 9 together with the inner lower end of the suspension housing 7.

The dash panel 5 is also called a dash lower,
As shown in the figure, the central lower portion is cut out in a trapezoidal shape to have a tunnel forming portion 5a. As shown in FIG. 2, the dash panel 5 has its left and right side edges joined to the rear ends of the wheel aprons 2, 2 while the vehicle body structure on the vehicle compartment 4 side formed behind the wheel aprons 2, 2. It is also joined so as to straddle each side frame 9. Further, the corners of the wheel aprons 2 and the dash panel 5 are joined to each other via the gusset member 10 to improve the joining strength and rigidity.

The suspension dash reinforcement 6 is provided as a pair on the left and right, and as shown in FIG. 1 showing the left side,
It is composed of a plate-like member that is bent like a folding screen. The one end 6a of the suspension dash reinforcement 6 is firmly and firmly joined so that the surface portion 6g extending in the left-right direction is attached to the front surface of the upper end portion of the suspension housing 7.
As shown in the figure, it is also joined to the wheel apron 2 via the gusset member 11 and the like. Then, the suspension dash reinforcement 6 extends inward in the left-right direction from the one end 6a, crosses the side frame 9, becomes an intermediate portion 6i, bends backward, and extends backward in parallel with the side frame 9,
Further, it has a bent shape in which it is bent inward obliquely, then turned laterally inward, and further bent obliquely backward to reach the other end 6b. A mounting flange 6c (see FIG. 3) is vertically formed on the other end 6b. The mounting flange 6c is joined to the dash panel 5 in the vicinity of the central portion in the left-right direction, and the lower portion of the mounting flange 6c has a third portion. As shown in the figure, they are joined along the tunnel forming portion 5a of the dash panel 5.

Further, the suspension dash reinforcement 6 is formed with a reinforcing flange 6h extending inward in the left-right direction from the one end 6a to the intermediate portion 6i above the side frame 9 along the lower edge of the surface portion 6g. The mounting flange 6d formed at the lower end of the intermediate portion 6i is joined to the side frame 9. Further, as shown in FIG. 1, on the upper peripheral portion of the suspension dash reinforcement 6,
A reinforcing flange 6e for improving rigidity is formed in a range from the wheel apron 2 at the upper end of the suspension housing 7 on the side of the one end 6a to the other end 6b. A bottom plate 12 having a substantially triangular shape is laid in a space surrounded by the dash panel 5 and the side frame 9 at a lower peripheral portion of the bottom plate 12. One side edge of the bottom plate 12 in the left-right direction is a suspension dash reinforcement 6. Mounting flange formed on the lower circumference of
While being joined to 6f, the other end 12a is joined to the side frame 9 and the rear end 12b is also joined to the dash panel 5. As a result, the side of the suspension dash reinforcement 6 from the intermediate portion 6i to the other end 6b is bent in the shape of a folding screen to form a three-dimensional shape in the front-rear direction, the left-right direction, and the up-down direction with the side frame 9 and the dash panel 5. By joining, the rigidity of the suspension dash reinforcement 6 itself is improved, and the mounting rigidity of the suspension dash reinforcement 6 to the side frame 9 and the dash lower 5 is also improved. The suspension dash reinforcement 6 arranged on the right side has a slightly different three-dimensional structure from the one on the left side, but is attached symmetrically.

With the above configuration, suspension dash reinforcement 6
One end 6a of the suspension is joined to the upper end of the suspension tower 3 and the intermediate portion 6i is joined to the side frame 9, so that it serves as a suspension spring and damper support and serves as an input point for the vibration load from the suspension. The upper end portion of the suspension tower 3 is supported by the side frame 9 via the suspension dash reinforcement 6, whereby the mounting rigidity of the suspension tower 3 can be increased. Therefore, the displacement of the upper end of the suspension tower 3 where the displacement becomes the largest due to the vibration load is regulated, and it is possible to reliably prevent the inward leaning phenomenon of the upper end of the suspension tower 3 inward in the left-right direction. it can.

And the suspension dash reinforcement 6 above,
The wheel apron 2 provided with the suspension tower 3 and the dash panel 5 allow the side frame 9
To the upper position of the engine room 1, a box-shaped closed cross-section is formed in a plan view, and the lower peripheral side of the box-shaped closed cross-section is a bottom plate 12 between the dash panel 5 and the side frame 9. Since it is closed by means of a three-dimensional structure, the front body around the suspension tower 7 and the vehicle body structure on the passenger compartment 4 side can be three-dimensionally coupled and reinforced via the dash panel 5. In addition, the other end 6b of the suspension dash reinforcement 6 is also joined to the dash panel 5 and the tunnel forming portion 5a below the dash panel 5 so that the dash panel 5 is vertically moved from the tunnel forming portion 5a position to the engine room 1 upper position. Since they are connected to each other, the bending rigidity of the front vehicle body can be remarkably improved together with the improvement in rigidity due to the closed cross section.

Therefore, by improving the mounting rigidity of the suspension tower 3 and the bending rigidity of the front vehicle body, the propagation of vibration input from the suspension tower 3 is effectively suppressed.
It is possible to effectively reduce the vehicle body vibration that is reduced and is particularly likely to occur in a high speed range exceeding 100 km / h.

Here, the effect of suppressing / reducing vibration by the above-mentioned two-node bending that tends to occur in the high speed range was compared and verified by the following simulation test.

That is, the skeleton model 21 composed of beam elements as shown in FIG. 4 with and without the suspension dash reinforcement 22 is the first cross member.
The left end 23a of 23 is used as an excitation point and is vertically excited at a frequency corresponding to the vehicle speed, and the side frame 24 and the second cross member 25
The inertance (cm / sec ² kgf), which is the vibration acceleration amplitude per unit of excitation force, was determined with the joint between and as the measurement point 26. The result is shown in FIG. It should be noted that those provided with the suspension dash reinforcement 22 are shown by broken lines, and those not provided are shown by solid lines.

Looking at Fig. 5 above, both are 22Hz (actual vehicle speed is about 140k
Inertance peaked around m) and two-joint bending occurred, but for those with Susdash Reinforcement 22, a smooth decline in inertance was seen from the low speed range, and Susdash reinforcement was observed. It is confirmed that the resistance to double bar bending is greater than that of the model without Ment 22. Therefore, it is effective to reduce the vibration by applying the suspension dash reinforcement 6 with the bottom plate 12 as in this example, and at 30 Hz (about 190 km /
Inertance peaks and triple barbending occurs even in the ultra-high speed range exceeding h), but even in this case, the inertance can be significantly reduced.

By providing the suspension dash reinforcement 6 in this way, it is possible to effectively suppress and reduce the bending of the vehicle body such as the two-joint bending that occurs in the high speed range, and to reduce the vibration and squeak. It is also possible to obtain a firm sense of stability without rattling even when cutting or bumping. Furthermore, since the suspension dash reinforcement 6 effectively improves the strength and rigidity of the front body structure around the engine room 1,
It goes without saying that the weight of other members such as the side frame 9 can be reduced to reduce the weight.

It should be noted that the space above the bottom plate 12 surrounded by the suspension dash reinforcement 6 can be effectively utilized for accommodating various supplementary parts.

(Effects of the Invention) As described above, according to the vehicle body structure of the vehicle of the present invention, the plate-shaped reinforcing member extends in the vertical range from the front side frame to the upper position of the engine room, and the suspension tower And the dash panel are arranged so as to be bent so as to be connected to each other, and the bottom plate is provided so as to be joined to the lower peripheral portion of the reinforcing member, the front side frame, and the dash panel. The wheel apron provided with the suspension tower and the dash panel can form a box-shaped closed section in a plan view, and the lower surface side of the box-shaped closed section is between the front side frame and the dash panel. Thus, the three-dimensional structure can be closed by the bottom plate. As a result, the rigidity of the plate-shaped reinforcing member itself can be improved, and the front body and the vehicle interior can be three-dimensionally coupled and reinforced by the reinforcing member having the increased rigidity.

Since one end of the reinforcing member is joined to the upper end of the suspension tower and the intermediate portion is joined to the front side frame, the reinforcing member serves as a support portion for the spring and damper of the suspension. The upper end portion of the suspension tower, which is the input point of the vibration load from, is supported by the front side frame, and the mounting rigidity of the suspension tower can be increased. Therefore, the displacement of the upper end of the suspension tower, which causes the largest displacement due to the vibration load, is surely regulated, and the occurrence of the inward leaning phenomenon of the upper end of the suspension tower in the left-right direction is surely prevented. You can

In addition, since the other end of the reinforcing member is also joined to the dash panel and the tunnel forming portion below the dash panel and is connected vertically from the tunnel forming portion position of the dash panel to the engine room upper position, the suspension described above is provided. The mounting rigidity of the tower can be further increased, and the bending rigidity of the front vehicle body can be improved. As a result, it is possible to effectively suppress and reduce the propagation of vibrations input from the suspension tower, and especially to increase the strength against double-joint bending that tends to occur in the high speed range, and effectively reduce vehicle body vibrations. it can.

[Brief description of drawings]

FIG. 1 is a perspective view of a suspension dash reinforcement in one embodiment of a vehicle body structure for an automobile according to the present invention, and FIG.
Figure is a plan view of the front body structure, and Figure 3 is III-III in Figure 2.
Fig. 4 is a perspective view showing how the skeleton model is attached, and Fig. 5 compares the inertance with respect to the vibration frequency corresponding to the vehicle speed for the model with and without the suspension dash reinforcement. It is a graph for doing. 1 ... Engine room, 2 ... Wheel apron, 3 ...
… Suspension tower, 4 …… Car interior, 5 …… Dash panel, 5a …… Tunnel formation part, 6 …… Susp dash reinforcement (reinforcing member), 6a …… One end, 6b ……
The other end, 6i ... intermediate part, 12 ... bottom plate, 12a ... other side edge of bottom plate, 12b ... rear edge of bottom plate.

Claims (1)

[Scope of utility model registration request] 1. A suspension tower is provided on each of the wheel aprons forming the left and right side walls of the engine room, and a dash panel that is connected to the rear position of each of the wheel aprons and separates the engine room from the vehicle compartment is located in the left-right direction. In the front body structure of an automobile, the front side frame is disposed so as to extend in the front-rear direction at a lower position on the inner side in the left-right direction of each suspension tower. A plate-shaped reinforcing member that spreads in the vertical direction up to the upper position and that is bent so as to connect the suspension towers and the dash panel to each other, the lower peripheral portion of the reinforcing member, the front side frame, and the dash panel. Is laid in a space surrounded by, and one side edge of the reinforcing member is In the peripheral part, the other side edge is provided with the front side frame, and the rear end edge is provided with a bottom plate joined to the dash panel respectively, and one end of the reinforcing member is joined to the upper end part of the suspension tower. The lower end of an intermediate portion extending inward in the left-right direction from the one end is joined to the front side frame, and the other end extends rearward from the intermediate portion, the dash panel, and a tunnel forming portion located under the dash panel. A front body structure of an automobile, characterized in that it is respectively joined to and.