JP3367864B2 - Car body structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is formed below a floor panel forming a floor surface of a vehicle compartment so as to extend substantially in the front-rear direction of a vehicle body, and a rear portion of the vehicle body is located outside of a front portion in the vehicle body width direction. A pair of floor frames are disposed, and the floor frame includes a bottom wall, a pair of side walls rising upward from each side edge of the bottom wall in the vehicle body width direction, and a horizontal direction from an upper edge of each side wall. The present invention relates to a vehicle body structure of an automobile configured by a pair of projecting flanges, and these flanges being fixed to the lower surface of the floor panel.

[0002]

2. Description of the Related Art A vehicle body structure of the above type used in cab-over trucks, buses, passenger cars or other types of automobiles is well known in the prior art (for example, JP-A-56-108).
357). According to this type of vehicle body structure, since the floor frame is arranged below the floor panel, the strength of the vehicle body can be increased, and even when a large external force acts on the vehicle body from the front-rear direction, The amount of permanent deformation can be suppressed.

At this time, in order to effectively increase the strength of the vehicle body by the floor frame, it is necessary to set the plate thickness of the floor frame to a large thickness and sufficiently increase the strength of the floor frame. However, when the plate thickness of the floor frame is set large in this way, the weight of the entire vehicle body increases,
Inevitably suffers from the cost increase.

Therefore, it is conceivable to attach a reinforcing member to the floor frame to reinforce the floor frame and increase the strength of the entire floor frame to reduce the plate thickness of the floor frame itself. For example, a substantially U-shaped reinforcing member extending along the bottom wall and both side walls of the floor frame is fixed to the inner side surface of the floor frame, or each end edge is fixed to both side walls of the floor frame to provide a horizontal reinforcing member. Of. However, according to a study conducted by the present inventor, it has become clear that simply attaching such a reinforcing member to the floor frame cannot increase the strength of the floor frame as desired, and a great effect cannot be expected. .

[0005]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above-mentioned novel recognition, and an object of the present invention is to enhance the strength of the vehicle body and to sufficiently reduce the thickness of the floor frame. An object of the present invention is to provide a car body structure that can be used.

[0006]

In order to achieve the above object, the present invention provides a vehicle body structure of the type described at the beginning,
A reinforcing plate extending to a transition portion between a front portion and a rear portion of the floor frame is arranged in a space defined by a bottom wall and both side walls of the floor frame and a floor panel, and the reinforcing plate divides the space into two parts. Thus, the upper end portion and the lower end portion are obliquely arranged obliquely downward, and at least the upper end portion of the upper end portion and the lower end portion is fixed to the floor frame, and each edge of the horizontal reinforcing member is A vehicle body structure of an automobile is proposed, which is fixed to each side wall of the floor frame (Claim 1).

At this time, in the vehicle body structure according to claim 1, when a compressive load is applied to the floor frame in the longitudinal direction thereof, a compressive load is applied to the reinforcing plate in the width direction thereof. It is advantageous that the inclined position of the reinforcing plate is defined and only the upper end of the upper end and the lower end of the reinforcing plate is fixed to the floor frame (claim 2).

Further, in the vehicle body structure according to claim 1, when a compressive load acts on the floor frame in a longitudinal direction thereof, a tensile load is applied to the reinforcing plate in a width direction thereof. It is advantageous that the reinforcing plate has a tilted position and both the upper end and the lower end of the reinforcing plate are fixed to the floor frame (claim 3).

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a side view showing a cab of a truck, which is an example of an automobile having a vehicle body structure according to the present invention, and FIG. 2 shows an outer contour of the cab by a chain line, and only some of the elements are shown. It is the top view shown by the solid line. The wording “front” or “rear” used in the present specification means the front and rear with respect to the forward direction F of the automobile, and the direction orthogonal to the front and rear direction is the width direction W of the vehicle body. .

1 and 2, a vehicle body 1 of a truck, that is, a cab, constitutes a roof panel 2 for partitioning an upper portion of a vehicle compartment, a quarter panel 3 for forming a side portion of the vehicle body 1, and a floor surface of the vehicle compartment. It has various panels such as a floor panel 4, a back panel 5 partitioning a rear portion of a vehicle compartment, and a front panel 6 located at a front portion of a vehicle body. Further, reference numeral 7 denotes a front pillar, and 8 denotes a windshield provided in the front portion of the vehicle compartment. Further, in the illustrated vehicle body structure, it is formed below the floor panel 4 so as to extend substantially in the front-rear direction of the vehicle body 1 as shown by the solid line, and the rear portion is positioned outside the front portion in the vehicle width direction. The floor frames 9 and 9a are arranged, and in this example, a pair of floor frames 9 and 9a are provided substantially symmetrically with respect to the center CL of the vehicle body 1 in the width direction W. These floor frames 9, 9a have substantially the same structure except that they are symmetrical.

As shown in FIGS. 3 and 4 which are enlarged sectional views taken along the lines III-III and IV-IV of FIG. 2, each floor frame 9, 9a includes a bottom wall 10, 10a and the bottom wall 10, 9. 10
a, a pair of side walls 11, 11a rising upward from each side edge in the vehicle body width direction W, and a pair of flanges 12, 1 protruding outward in the horizontal direction from the upper edge of each side wall 11, 11a.
2a, bottom wall 10, 10a, both side walls 1
1, 11a and both flanges 12, 12a integrally extend long in the front-rear direction of the vehicle body 1. Each floor frame 9, 9a has a substantially U-shaped cross section. Further, these flanges 12 and 12a are fixed to the lower side surface of the floor panel 4 by spot welding, as shown by X marks in FIGS. 3 and 4.

The floor frames 9 and 9a configured as described above are respectively supported by the chassis frame 13 via an intermediate member (not shown), which allows the vehicle body 1 to be supported.
Is mounted on the chassis frame 13. A luggage carrier (not shown) is supported on the chassis frame portion behind the vehicle body 1. Each panel of the vehicle body 1 described above, the front pillar 7, and the floor frames 9 and 9a are made of a high-strength material such as a steel plate.

As shown in FIGS. 3 and 4, each floor frame 9, 9a is fixed with substantially U-shaped first reinforcing members 14, 14a arranged along the inner side surface thereof, and horizontally. The respective end edges of the second reinforcing members 15 and 15a in the standing position are fixed to the side walls 11 and 11a of the floor frames 9 and 9a via the first reinforcing members 14 and 14a. These reinforcing members 14, 14b, 15, 15b are also made of a high-strength material such as a steel plate, and are provided over the entire length of each floor frame 9, 9a or a part thereof.

Here, for example, for a running truck,
If a large external force P acts from the front, the vehicle body 1
Since the loading platform is located behind the vehicle, a large load is applied to the vehicle body 1 from the front and the rear. As a result, the vehicle body 1 tends to compressively deform, but at this time, the permanent deformation of the vehicle body 1, that is, its plastic deformation is suppressed by the reinforcing function of the floor frames 9 and 9a.

As described above, the strength of the vehicle body 1 can be increased by the floor frames 9 and 9a, but conventionally, in order to surely increase the strength, the floor frame is made of a thick plate material. . For this reason, the weight of the vehicle body is increased, and the cost thereof is inevitably inevitable.

As described above, the floor frames 9 and 9a of this embodiment include the first and second reinforcing members 14, 14a, 15 and 1 as described above.
5a is fixed, and by these, the floor frames 9, 9
Although a is reinforced, the floor frames 9 and 9a cannot be sufficiently reinforced with only the reinforcing member, and the plate thickness of the frames 9 and 9a cannot be sufficiently reduced.

The present inventor has been able to clarify the following facts as a result of analyzing the plastic deformation of the floor frame in order to clarify the cause.

In FIG. 9 (b), the truck receives a large external force P from the front, and a compressive load acts in the longitudinal direction on the floor frame 9 to which the first and second reinforcing members 14 and 15 are attached. 9A is an explanatory diagram showing a permanent deformation state of the floor frame 9 at this time, and FIG. 9A shows a state before the deformation. As can be seen from FIG. 9B, when a large compressive load acts on the floor frame 9,
Is crushed so that the cross-sectional shapes of its bottom wall 10 and both side walls 11 form a parallelogram. As shown in (a) of FIG. 9, the floor frame 9 having a substantially rectangular cross-sectional shape before the deformation is permanently deformed like a match box is crushed.
The other floor frame 9a is crushed and deformed symmetrically with the floor frame 9 shown in FIG. 9B.

Here, the first and second reinforcing members 14 and 15 are fixed to the floor frame 9, but these members 14 and 15 prevent the floor frame 9 from being crushed and deformed into a parallelogram shape. It cannot act as an effective deterrent. Once the floor frame 9 is permanently deformed into a parallelogram shape, the change in the cross-sectional shape causes the cross-sectional strength to be extremely reduced. For this reason, the floor frame 9 cannot be effectively reinforced only by providing the first and second reinforcing members 14 and 15. Conventionally, the plate thickness is set to an extremely large value, and the parallel four sides There was no choice but to prevent it from collapsing and deforming into a shape.

Therefore, in the vehicle body structure of this example, paying attention to the above-mentioned points, as shown in FIGS. 3 and 4, the bottom walls 10, 10a of the floor frames 9, 9a and the side walls 11, 1 are formed.
Space S defined by 1a and floor frame 4
Reinforcing plates 16 and 16a that extend over at least a part of the floor frames 9 and 9a in the longitudinal direction are arranged therein. The reinforcing plates 16 and 16a are arranged obliquely downward from the upper end portions 17 and 17a toward the lower end portions 18 and 18a so as to divide the space S into two. In the illustrated example, as shown by Q in FIG. 2, each reinforcing plate 16, 16a is provided in the range of the transition portion between the front part and the rear part of the floor frame 9, 9a. It is also possible to extend the reinforcing plates 16 and 16a over the entire length of 9a. Further, as will be described later, the reinforcing plates 16 and 16a
Of the floor frame 9, at least the upper end portions 17 and 17a of the upper end portions 17 and 17a and the lower end portions 18 and 18a.
It is fixed to 9a.

In the example shown in FIGS. 3 and 4, the reinforcing plate 1
The upper end portions 17 and 17a of 6, 16a are located on the side away from the center CL of the vehicle body 1 in the width direction, that is, on the outer side in the vehicle width direction,
The lower end portions 18, 18a occupy positions closer to the center CL in the width direction of the vehicle body 1, and their upper end portions 17, 17a and lower end portions 18, 1
8a is the first reinforcing member 14, 14 by arc welding AC
The reinforcing plates 16 and 16a are fixed to the floor frames 9 and 9a.

As shown in FIG. 9B, when a compressive load is applied to the floor frame 9 in its longitudinal direction, the floor frame 9 tends to be deformed by collapsing its cross-section into a parallelogram. However, at this time, since the reinforcing plate 16 arranged in an inclined position is provided inside the floor frame 9, this reinforcing plate 16 is used as the floor frame 9.
The floor frame 9 acts to prevent the crushing deformation of the floor frame 9
To prevent large permanent deformation. 5 (a),
(B) is the floor frame 9 when the reinforcing plate 16 is provided
It is an explanatory view showing the state before the deformation and after the permanent deformation. From this figure, it can be understood that the reinforcing plate 16 can effectively suppress the permanent deformation such that the floor frame 9 is crushed. The reinforcing plate 16a shown in FIG. 4 acts in exactly the same manner, and prevents the floor frame 9a from being deformed.

As described above, when a compressive load is applied to the floor frames 9, 9a in the longitudinal direction thereof, the reinforcing plates 16, 16a can prevent or suppress permanent deformation of the floor frames 9, 9a. Each floor frame 9, 9a exerts its original reinforcing effect. Therefore, even if the thickness of the floor frames 9 and 9a is set to be significantly smaller than the conventional one, the strength of the vehicle body 1 can be maintained, the weight of the vehicle body 1 can be reduced, and the cost thereof can be reduced. Become. In addition, the first and second reinforcing members 14, 14
Even if a, 15, and 15a are omitted, the reinforcing plates 16 and 16a can prevent the floor frames 9 and 9a from being deformed. This is the same in the example described later.

As shown in FIG. 6, the inclined position of the reinforcing plate 6 can be reversed from that in FIG. The same applies to the reinforcing plate 16a provided on the other floor frame 8a.

Here, in the example shown in FIGS. 3 and 4, when an external force P is applied to the vehicle body 1 and a compressive load acts on the floor frames 9 and 9a in the longitudinal direction thereof, as shown in FIG. As is clear from the deformed state of the floor frame shown in b), a compressive load is applied to the reinforcing plates 16 and 16a by the floor frames 9 and 9a in the width direction of the reinforcing plates 16 and 16a. Therefore, in this case, if the upper end portions 17 and 17a of the reinforcing plates 16 and 16a are fixed to the floor frames 9 and 9a, the lower end portions 18 and 17a thereof are
Even if 18a is not fixed to the floor frames 9 and 9a, the reinforcing plates 16 and 16a exert the above-mentioned reinforcing function. That is, when a compressive load is applied to the floor frames 9, 9a in the longitudinal direction thereof, the reinforcing plates 16, 16a
On the other hand, the inclined positions of the reinforcing plates 16 and 16a are determined so that the compressive load is applied in the width direction, and the reinforcing plates 16 and 16a are
Of the upper end portions 17 and 17a and the lower end portions 18 and 18a of a,
Only the upper end can be fixed to the floor frames 9, 9a. Thereby, the reinforcing plates 16 and 16a
It is not necessary to apply welding AC to the lower end portions 18 and 18a of the floor frames 9 and 9a of the reinforcing plates 16 and 16a.
Assembly work can be simplified and the cost can be reduced.

On the other hand, when the reinforcing plate 16 is arranged as shown in FIG. 6, when a compressive load is applied to the floor frame 9 in its longitudinal direction, the floor frame 9 is deformed as shown in FIG. 9 (b). As is apparent, a tensile load acts on the reinforcing plate 16. In this case, the reinforcing plate 16 cannot fulfill the function of reinforcing the floor frame 9 unless both the upper end 17 and the lower end 18 of the reinforcing plate 16 are fixed to the floor frame 9. That is, in this case, when the compressive load acts on the floor frame 9 in the longitudinal direction thereof, the inclined position of the reinforcing plate 16 is determined so that the tensile load is applied to the reinforcing plate 16 in the width direction thereof. The upper end portion 17 and the lower end portion 18 of the reinforcing plate 16 are both fixed to the floor frame 9. The same applies to the reinforcing plate 16a provided on the other floor frame 9a.

According to this structure, the upper end portion 1 of the reinforcing plate 16 is
It is necessary to apply welding AC to 7 and the lower end portion 18,
When a compressive load is applied to the floor frame 9, the reinforcing plate 1
Since a tensile load acts on 6, the advantage of being able to prevent bending deformation even if the plate thickness is thin is obtained as compared with the case where a compressive load is applied to this.

As described above, the reinforcing plates 16 and 16a have the upper end portions 17 and 17a and the lower end portions 18 and 18a, at least the upper end portions 17 and 17a thereof being fixed to the floor frames 9 and 9a.

Reinforcing plate 1 for floor frames 9, 9a
The assembling modes of 6, 16a are not limited to the examples described above, and can be selected as appropriate. For example, as shown in FIG. 7, the upper end 17 of the reinforcing plate 16 is brought into close contact with the side wall 11 of the floor frame 9 in a large area, and the upper end 17 is sandwiched between the side wall 11 and the second reinforcing member 15, and these are marked with a cross mark. It can also be fixed by spot welding, as indicated by. In addition, in the example of FIG. 7, the lower end portion 18 of the reinforcing plate 16 is spot-welded to the bottom wall 10 of the floor frame 9, and the extension portion 19 is formed on the lower end portion 18, and the extension portion 19 is formed. Is closely adhered to the side wall 11, and the upper end portion is sandwiched between the side wall 11 and the second reinforcing member 15, and these are fixed by spot welding. In this example, the first reinforcing member is not provided.

Further, in the example shown in FIG. 8, the upper end 17 of the reinforcing plate 16 has the same structure as that of FIG. 7, but the lower end 18 is separated from the inner surface of the floor frame 9. When a compressive load acts on the floor frame 9 shown here,
Since the lower end portion 18 of the reinforcing plate 16 hits the floor frame 9 and a compressive load acts on the reinforcing plate 16, the lower end portion 18 may be separated from the floor frame 9 in a normal state.

The present invention can be widely applied not only to trucks but also to car body structures of automobiles such as buses and passenger cars.

[0033]

According to the vehicle body structure of the first aspect of the present invention, the sloping reinforcing plates can effectively suppress the crushing deformation of the floor frame, and thus the thickness of the floor frame can be made smaller than the conventional one. It can be set significantly smaller.

According to the vehicle body structure of the second aspect, since the lower end portion of the reinforcing plate is not fixed to the floor frame,
The reinforcing plate can be easily assembled to the floor frame.

According to the vehicle body structure of the third aspect, when a compressive load is applied to the floor frame in its longitudinal direction, a tensile load is applied to the reinforcing plate. Therefore, the plate thickness of the reinforcing plate is set small. However, the reinforcing plate surely reinforces the floor frame.

[Brief description of drawings]

FIG. 1 is a side view showing a cab of a truck.

FIG. 2 is a schematic plan view in which the contour of the cab shown in FIG. 1 is represented by a chain line and only some of the elements are represented by a solid line.

FIG. 3 is an enlarged sectional view taken along line III-III of FIG.

FIG. 4 is an enlarged sectional view taken along line IV-IV of FIG.

FIG. 5 is an explanatory cross-sectional view showing a state before deformation and after permanent deformation of the floor frame when the reinforcing plate is provided.

FIG. 6 is a sectional view similar to FIG. 3, showing an example in which the inclination state of the reinforcing plate is changed.

FIG. 7 is a sectional view similar to FIG. 3, showing another example of the reinforcing plate.

FIG. 8 is a sectional view similar to FIG. 3, showing still another example of the reinforcing plate.

FIG. 9 is a cross-sectional explanatory view showing a state before deformation and after permanent deformation of the floor frame when there is no reinforcing plate.

[Explanation of symbols]

1 car body 4 floor panels 9 floor frame 9a floor frame 10 bottom wall 10a bottom wall 11 Side wall 11a side wall 12 flange 12a flange 16 Reinforcement plate 16a Reinforcing plate 17 Upper end 17a upper end 18 Lower end 18a lower end W width direction

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-55172 (JP, A) JP-A-56-108357 (JP, A) Actually open Sho 61-16977 (JP, U) Actual-open Flat 1- 112178 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B62D 25/20 B62D 33/06

Claims (3)

(57) [Claims] 1. A pair of floor frames formed below a floor panel constituting a floor surface of a vehicle compartment, extending substantially in the front-rear direction of the vehicle body, and having a rear portion located outside the front portion in the vehicle width direction. The floor frame is disposed, a bottom wall, a pair of side walls that rise upward from each side edge of the bottom wall in the vehicle body width direction, and a pair of flanges that horizontally protrude from the upper edge of each side wall. In the vehicle body structure of an automobile, wherein the flanges are fixed to the lower surface of the floor panel, the front of the floor frame is provided in the space defined by the bottom wall and both side walls of the floor frame and the floor panel. A reinforcing plate extending to a transition portion between the rear portion and the rear portion is arranged, and the reinforcing plate is inclined and arranged obliquely downward from the upper end portion to the lower end portion so as to divide the space into two, and the upper end portion Body structure of a motor vehicle in which at least the upper end portion, characterized in that secured to the floor frame, and each edge of the horizontal state position of the reinforcing member is secured to each side wall of the floor frame of the ends. 2. The inclined position of the reinforcing plate is determined so that when a compressive load is applied to the floor frame in its longitudinal direction, a compressive load is applied to the reinforcing plate in its width direction, and The vehicle body structure according to claim 1, wherein only the upper end portion of the reinforcing plate is fixed to the floor frame. 3. The inclined position of the reinforcing plate is determined so that a tensile load is applied to the reinforcing plate in the width direction when a compressive load is applied to the floor frame in the longitudinal direction thereof, and The vehicle body structure for an automobile according to claim 1, wherein both the upper end and the lower end of the reinforcing plate are fixed to the floor frame.