JP2003252251A - Floor structure of vehicle body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress vertical displacement of a seat for an occupant even if a floor frame is vertically displaced in a floor structure of a vehicle body. <P>SOLUTION: A part of portion of each cross member 13 crossing with a floor frame 12 in a plan view is divided in the width direction and it constitutes a displacement independent structure where the divided part 13e is independent of the vertical displacement of the floor frame 12 about the vertical displacement in the seat mounting part 13c of each seat 20. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floor structure of a vehicle body, and more particularly to improvement of a cross member to which a passenger seat is connected.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 10, a floor panel 11 disposed under a vehicle body of an automobile is provided with a floor frame 12 extending in the front-rear direction of the vehicle body and a cross member 13 extending in the width direction. Has been.

The floor frame 12 is a floor panel 1
1, the cross member 13 is installed on the upper surface of the floor panel 11.

The floor frame 12 and the cross member 13 absorb the input impact load by deforming themselves to some extent, and the floor frame 12 is input in the longitudinal direction of the vehicle body. The impact load is absorbed, and the cross member 13 absorbs the impact load input from the side of the vehicle body.

Further, the cross member 13 is formed with a seat attachment portion 13c to which the occupant seat 20 is attached. A base portion 21 extending in the width direction of the vehicle body and provided at the lower portion of the occupant seat 20 is coupled to the seat mounting portion 13c by fastening means such as bolts and nuts.

[0006]

By the way, as shown in FIG. 11, when a shock load is applied in the front-rear direction of the vehicle body, the floor frame 12 is deformed as shown by a chain double-dashed line in order to absorb the shock load. . Then, due to the deformation at this time, each part of the floor frame 12 is displaced upward or downward from its original position.

Since the floor frame 12 intersects the cross member 13 via the floor panel 11, the displacement of the intersecting portion of the floor frame 12 becomes the displacement of the cross member 13 as it is.

That is, as shown in FIG. 12 showing the back surface of the occupant's seat 20 as viewed from the direction of arrow A in FIG. 11, the cross member 13 has rigidity due to its rigidity.
, Not only the portion intersecting with the floor frame 12, but the entire body is displaced upward uniformly (FIG. 12B).

Therefore, the seat mounting portion 13c of the cross member 13 is also displaced upward by the displacement of the floor frame 12, and the height position of the seat mounting portion 13c with respect to the floor panel 11 is before the deformation of the floor frame 12 (see FIG. It becomes H2 which greatly exceeds H1 of (a)).

Since the occupant seat 20 is fastened to the seat mounting portion 13c as described above, the uniform vertical displacement of the cross member 13 causes the occupant seat 20 to be displaced in the vertical direction. The vertical displacement is
This may affect the restraint of the occupant seated in the occupant seat 20.

Further, as a technique of this kind, Japanese Patent Laid-Open No. 6-1 is known.
There is one described in Japanese Patent No. 71551.

According to the technique described in this publication, the rear end of the floor frame installed on the lower surface of the floor panel is set in a range between the vehicle body front flange and the vehicle body rear flange of the cross member installed on the upper surface of the floor panel. It is configured to be located at.

When the floor frame is displaced rearward due to the impact at the time of a collision, the floor panel portion between the rear end of the floor frame and the rear flange of the cross member absorbs this impact as a buffer area, and The member is prevented from being displaced rearward.

However, also in this technique, when an impact load exceeding the load that can be absorbed by the buffer area is applied, the floor frame is displaced upward and pushes up the cross member, as in the case described above. However, the above problems cannot be solved.

The present invention has been made in view of the above circumstances, and provides a floor structure of a vehicle body capable of suppressing the vertical displacement of the occupant seat even when the floor frame is vertically displaced. The purpose is to do.

[0016]

In order to solve the above problems, a floor structure of a vehicle body according to claim 1 of the present invention is a floor panel of a vehicle body and a lower surface of the floor panel extending in the front-back direction of the vehicle body. Installed on the upper surface of the floor panel extending in the width direction of the vehicle body so as to intersect the floor frame,
A floor structure of a vehicle body having a cross member to which a base portion of each occupant seat is joined, wherein a vertical displacement in a joining portion of the occupant seat is a portion of the floor frame that intersects with the cross member. In the above-mentioned cross member, a displacement-independent structure that is independent of displacement in the vertical direction is formed.

The term “intersection” includes not only an intersection in a mathematically strict sense but also a so-called “twisted position state” of “intersecting in a plan view”.

That is, since the floor frame is installed on the lower surface side of the floor panel and the cross member is installed on the upper surface side of the floor panel, the floor frame and the cross member do not exist on the same surface. Therefore, in a mathematically strict sense, the floor frame and the cross member do not intersect.

According to the floor structure of the vehicle body of the present invention having the above-described structure, for example, even if an impact load is applied in the front-rear direction of the vehicle body and the floor frame is displaced upward or downward with respect to the floor panel. , The displacement independent structure formed on the cross member releases this displacement and suppresses the displacement at the joint portion of the occupant seat coupled to the cross member, so that the occupant seated on the occupant seat is prevented. It is possible to reduce a change in restraint with respect to an occupant that may occur due to displacement in the vertical direction.

The floor structure for a vehicle body according to claim 2 of the present invention is a structure in which the displacement independent structure divides the cross member in a width direction at a portion intersecting with the floor frame. It is characterized by the floor structure of the vehicle body described in.

According to the floor structure for a vehicle body of the second aspect of the invention thus constructed, the following actions and effects are exhibited in addition to the actions and effects of the first aspect.

That is, when the floor frame is displaced vertically with respect to the floor panel, the intersecting portions of the cross members are also displaced vertically, but the cross members are divided in the vehicle width direction at the intersecting portions. Therefore, the entire cross member does not displace uniformly in the vertical direction, and each of the two sub cross members obtained by dividing this cross member has its divided end on the floor frame. It follows that it is vertically displaced but the other end is not displaced.

Therefore, the vertical displacement of the joint between the divided cross member and the base of the occupant seat is suppressed more than the displacement when the cross member is not divided.

Further, in order to suppress the displacement of the joint portion of the occupant seat, there is a possibility that the occupant seated on the occupant seat may be displaced in the vertical direction.
It is possible to reduce changes in restraint of the occupant.

Further, in this displacement independent structure, since the cross member is simply divided at a predetermined position, it is possible to suppress an increase in manufacturing cost.

Further, in the floor structure for a vehicle body according to a third aspect of the present invention, portions of the divided cross members that are close to each other are joined by a connecting member that is thinner than the cross member. The vehicle body floor structure according to claim 2 is characterized.

According to the floor structure for a vehicle body of the third aspect of the invention thus constructed, the following actions and effects are exhibited in addition to the actions and effects of the second aspect.

That is, the two cross members obtained by the division are simply divided because the adjacent portions between the cross members are joined by the connecting member which is thinner than the cross member. The strength against the load input from the side of the vehicle body can be improved as compared with the cross member divided into two parts.

Further, in the floor structure for a vehicle body according to a fourth aspect of the present invention, at least a part of the floor frame is installed on an upper surface of the floor panel, and the divided cross members are close to each other. The floor structure of a vehicle body according to claim 2 or 3, characterized in that the two are joined together by a part of a floor frame installed on an upper surface of the floor panel.

Here, as for at least a part of the floor frame installed on the upper surface of the floor panel, at least a part of the floor frame installed on the lower surface of the floor panel is taken out and installed on the upper surface of the floor panel as it is. No need.

Even if the floor frame installed on the lower surface of the floor panel is to be installed on the upper surface of the floor panel as it is, since the uneven shape of the floor panel is different between the upper surface and the lower surface, the floor installed on the lower surface of the floor panel is different. Generally, the frame cannot be installed on the upper surface as it is.

Therefore, "at least a part of the floor frame is installed on the upper surface of the floor panel" means
It is meant to include "installed on the upper surface of the floor panel after appropriately changing at least a part of the floor frame into a shape suitable for installation on the upper surface of the floor panel".

According to the floor structure for a vehicle body of the fourth aspect of the invention thus constructed, the following actions and effects are exhibited in addition to the actions and effects of the corresponding claims of the second and third aspects. .

That is, even if the floor frame installed on the lower surface of the floor panel is displaced upward or downward with respect to the floor panel due to an impact load applied in the front-rear direction of the vehicle body, a part installed on the upper surface of the floor panel. Since the floor frame is independent of the floor frame installed on the lower surface of the floor panel, the impact load is not directly transmitted to the part of the floor frames from the floor frame on the lower surface of the floor panel.

Further, the two cross members obtained by the division are divided because the adjacent portions between these cross members are joined by a part of the floor frame installed on the upper surface of the floor panel. The strength against the load input from the lateral side of the vehicle body can be improved as compared with the cross member that is divided into two parts.

Further, compared with the floor structure joined by thin plate connecting members, since it is further joined by a part of the floor frame installed on the upper surface of the floor panel, the load applied from the side of the vehicle body The strength against it can be further improved.

Moreover, since a part of the floor frame installed on the upper surface of the floor panel replaces a part of the floor frame installed on the lower surface of the floor panel, an increase in the number of members can be avoided. It is possible to suppress an increase in manufacturing cost.

Further, in the floor structure for a vehicle body according to claim 5 of the present invention, the base portion of the passenger seat is formed in two rows in front of and behind the vehicle body, and the cross member corresponds to the base portion of the passenger seat. 5. The displacement independent structure is formed on at least a cross member corresponding to the rear of the vehicle body, the cross member being installed in two rows. Characterized by the floor structure of the vehicle body.

According to the floor structure for a vehicle body of the present invention thus configured, the following actions and effects are obtained in addition to the actions and effects according to the corresponding claims of the first to fourth aspects. .

That is, when an impact load is input in the front-rear direction of the vehicle body and the floor frame absorbs the impact load and is deformed and is displaced upward or downward with respect to the floor panel, the displacement in the vertical direction is the rearward direction of the vehicle body. It will be bigger on the side.

Therefore, since the displacement independent structure formed on at least the cross member on the side corresponding to the rear of the vehicle body gives priority to a larger vertical displacement generated on the rear side of the vehicle body, it is independent. It is possible to reduce a change in restraint with respect to an occupant that may occur due to vertical displacement of the occupant seated in the seat.

Further, in the floor structure for a vehicle body according to claim 6 of the present invention, the cross member is provided from substantially the center of the floor panel to a side edge, and the intersecting portion is the cross member. A vehicle body width direction substantially center portion and a vehicle body width direction substantially center portion of the occupant seat, wherein a connecting portion of the cross member and the occupant seat base portion is arranged substantially symmetrically with respect to the intersecting portion. Claim 1
5. The floor structure of the vehicle body according to any one of items 1 to 5 is characterized.

According to the floor structure for a vehicle body of claim 6 thus constructed, the following actions and effects are obtained in addition to the actions and effects according to the corresponding claims of claims 1 to 5. .

That is, since the intersecting portion corresponds to a substantially central portion of the cross member in the vehicle body width direction, the cross member absorbs the vertical displacement of the floor frame at the substantially central portion.

Therefore, the cross member is deformed into a substantially symmetrical shape with the portion where the displacement is independent interposed therebetween, and the occupant seat is symmetrically connected to the substantially central portion of the cross member deformed into the substantially symmetrical shape. Therefore, even if the displacement independent structure cannot completely displace the vertical displacement of the floor frame, the vertical displacement of the cross member at the joint with the base of the occupant seat is It is almost symmetrical with the left side, that is, the same height,
The occupant's seat is kept substantially horizontal in the width direction of the vehicle body even after the displacement.

Therefore, it is possible to reduce the change in the restraint in the vehicle width direction for the occupant seated on the occupant seat.

[0047]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of a floor structure for a vehicle body according to the present invention will be described below with reference to the drawings.

First, a floor structure 10 for a vehicle body, which is an embodiment of the present invention, is shown in FIGS. The floor structure 10 includes a floor panel 11, a floor frame 12 installed on the lower surface of the floor panel 11, and a cross member 13 installed on the upper surface of the floor panel 11.

The floor panel 11 is formed with a tunnel portion 11a extending in the front-rear direction at a substantial center in the vehicle width direction, and partitions the driver seat side and the passenger seat side.

Further, flanges 11c joined to the door opening are formed at both ends in the vehicle width direction.

The illustrated floor panel 11 is shown in a simplified manner, and may be constructed by joining two or more panels. Further, the driver's seat side and the passenger's seat side do not have to be symmetrical and need not have the tunnel portion 11.

The floor frame 12 has a substantially hat-shaped cross section, and extends in the vehicle front-rear direction at substantially the center of each of the driver seat side and the passenger seat side. The flange 12a is joined to the floor panel 11 by spot welding.

The cross member 13 has a substantially hat-shaped cross section, extends in the vehicle width direction so as to intersect with the floor frame 12 in a plan view, and is provided with two rows each on the driver side and the passenger side. There is. As with the floor frame 12, the flange 13d is joined to the floor panel 11 by spot welding.

One of the side ends of these cross members 13 contacts the flange 11c of the floor panel 11,
The other is in contact with a slope 11b forming the tunnel portion 11a of the floor panel 11.

Further, seat attachment portions (joint portions) 13c to which the driver seat (not shown) and the base portion 21 of the passenger seat 20 are fastened are formed in the vicinity of both end portions of the upper surface of each cross member 13. There is.

A portion of each cross member 13 that intersects with the floor frame 12 in a plan view (hereinafter simply referred to as "intersecting portion"), that is, substantially the center of the cross member 13, is divided in the width direction. There is. This divided portion 13e makes the vertical displacement of the seat mounting portion 13c of each seat 20 independent of the vertical displacement of the floor frame 12 and allows the seat mounting portion 1 of each seat 20 to be separated.
3c has a displacement independent structure that suppresses displacement in the vertical direction.

The sub-cross members 13a and 13b are provided.
The lengths L1 and L2 from the divided portion 13e to the seat mounting portion 13c are substantially equal to each other, and with respect to the divided portion 13e,
The left and right seat mounting portions 13c are formed at substantially symmetrical positions.

Next, the operation of the floor structure of this embodiment will be described.

Here, when an impact load is applied to the vehicle provided with the floor structure 10 of the present embodiment from the front-rear direction of the vehicle body, the floor frame 12 is vertically moved as in the conventional floor structure shown in FIG. Transformed into a cross member 13
It is displaced upward at the intersection with.

This state is shown in FIG. 3 corresponding to the arrow A in FIG. The figure (a) shows the state before the impact load is input, and the figure (b) shows the state after the impact load is input.

In a state before the floor frame 12 is displaced, the upper surface of the cross member 13 has the floor panel 1
It is located at a constant height H1 with respect to 1.

When an impact load is input and the floor frame 12 is displaced upward in the direction of arrow U, the upper surface of the cross member 13 is located at a position higher than the height H1 with respect to the floor panel 11 in the divided portion 13e. It is displaced up to H3 and greatly rises like the height position H2 of the cross member in the conventional floor structure shown in FIG.

However, the entire cross member 13 is not uniformly displaced in the upward direction, and two sub cross members 13a, 13 obtained by dividing the cross member 13 are obtained.
The height position H4 of the seat mounting portion 13c with respect to the base portion 21 of the seat 20 of b is lower than the height position H3 of the divided portion 13e, and there is no great difference from the height position H1 before the impact load input. ing.

As described above, the displacement of the floor frame 12 with respect to the seat mounting portion 13c is suppressed by the divided portion 13e.

Therefore, the height position of the occupant seated on the seat 20 hardly changes before and after the impact load is input. Therefore, the change in restraint on the occupant is small.

Further, each sub cross member 13a, 13b
Since the lengths L1 and L2 from the divided portion 13e to the seat mounting portion 13c are substantially equal and substantially symmetrical, the height positions of both seat mounting portions 13c are substantially equal to H4.

Therefore, the seat 20 is kept substantially horizontal in the vehicle width direction, and the change in the restraint property in the vehicle width direction for the occupant seated on the seat 20 is reduced.

As described above, according to the floor structure 10 for a vehicle body of the present embodiment, a change in restraint with respect to an occupant when an impact load in the vehicle front-rear direction is input can be reduced as compared with the conventional floor structure. it can.

Further, changes in restraint in the vehicle width direction can be reduced.

Furthermore, the floor structure 10 of this embodiment is
As the displacement independent structure, the cross member 13 is divided into the divided portions 13
Since e is formed, an increase in manufacturing cost can be suppressed.

[0071]

[Modification 1] In the floor structure of the above-mentioned embodiment, the seat member 1 is formed by forming the divided portion 13e in the cross member 13.
Although the displacement independent structure in 3c is adopted, this divided portion 13
FIG. 4 shows a modified example 1 in which portions of e, which are close to each other between the sub cross members 13a and 13b, are joined by a connecting plate 14 which is thinner than the cross member.

In the illustrated modified example 1, a connecting plate 14 is joined to the front surfaces 13f of both sub cross members 13a and 13b.

Thus, the divided portion 13e is connected to the connecting plate 14
According to the structure joined by, in addition to the effect of the floor structure shown in FIGS. 1 and 2, the strength against a load input from the side of the vehicle body can be improved.

[0074]

[Modification 2] FIG. 5 shows the reinforcing plate 14 shown in Modification 1.
Shows a modified example 2 in which the above is joined to the upper surfaces 13g of both the sub cross members 13a and 13b.

Thus, the divided portion 13e is connected to the connecting plate 14
According to the structure joined by, in addition to the effect of the floor structure shown in FIGS. 1 and 2, the strength against a load input from the side of the vehicle body can be improved as in the first modification.

[0076]

[Modification 3] Similar to Modifications 1 and 2, FIG. 6 shows Modification 3 in which parts of the divided portion 13e of the cross member 13 which are adjacent to each other between the sub cross members 13a and 13b are joined together. It is a thing.

In this modified example 3, the floor frame 12 is
A first floor frame 12b corresponding to the vehicle body front side of the cross member 13 and a second floor frame 12c corresponding to the vehicle body rear side of the cross member 13 are provided. The first floor frame 12b is the same as in the above-described embodiments. The flange 12a is spot-welded on the lower surface of the floor panel 11, and the second floor frame 12c is spot-welded on the upper surface of the floor panel 11.

Then, as shown in FIG. 6 and FIG. 7 which is a sectional view taken along the line BB, the second floor frame 1
The front end face 12e of 2c has both sub-cross members 13a, 13
Second floor frame 12c joined to front surface 13f of b
12d of the front end upper surface of both sub cross members 13a, 13b
13g, and the side surface 12f of the second floor frame 12c is joined to a flange 13h formed by bending the rear surface of each sub-cross member 13a, 13b rearward.

As described above, according to the structure in which the divided portion 13e is joined by the second floor frame 12c which is a part of the floor frame 12, an impact load is applied in the front-rear direction of the vehicle body so that the first floor frame 12b becomes the floor panel 11. The second floor frame 12c is independent of the first floor frame 12b even when it is displaced upward with respect to the second floor frame 12c.
The impact load is not directly transmitted to the floor frame 12c from the first floor frame 12b.

Further, similar to the first and second modifications, in addition to the effect of the floor structure shown in FIGS. 1 and 2, the strength against a load input from the side of the vehicle body can be improved.

Moreover, since the second floor frame 12c for joining the divided portions 13e replaces a part of the floor frame 12 installed on the lower surface of the floor panel 11 conventionally, the number of members is substantially increased. This can be avoided, and the increase in manufacturing cost can be suppressed.

[0082]

[Modification 4] In Modification 4 shown in FIG. 8, similarly to Modification 3, the floor frame 12 corresponds to the first floor frame 12b corresponding to the front side of the vehicle body with respect to the cross member 13 and the rear frame corresponding to the rear side of the vehicle. The first floor frame 12b is installed by spot welding the flange 12a to the lower surface of the floor panel 11 like the above-described embodiments, and the second floor frame 12g is composed of two floor frames 12g.
The flange 12a is spot-welded and installed on the upper surface of the floor panel 11.

The side surface 12f of the second floor frame 12g is joined to a flange 13h formed by bending the rear surface of each sub cross member 13a, 13b rearward.

Further, a bulkhead (reinforcing material) 15 for closing the hat-shaped cross-section opening of the second floor frame 12g and preventing the deformation of the second floor frame 12g is joined to the front end surface of the second floor frame 12g. ing.

In this way, according to the structure in which the divided portion 13e is joined by the second floor frame 12g which is a part of the floor frame 12, as in Modifications 1 to 3, FIG.
In addition to the effect of the floor structure shown in and 2, it is possible to improve the strength against a load input from the side of the vehicle body.

Further, since the second floor frame 12g is reinforced by the bulkhead 15, it is possible to further improve the strength against the impact load from the side of the vehicle body.

Moreover, as in the third modification, the divided portion 13
The second floor frame 12g that joins e has been
Since it replaces a part of the floor frame 12 installed on the lower surface of the floor panel 11, an increase in the number of members can be substantially avoided and an increase in manufacturing cost can be suppressed.

In the modified examples 3 and 4 described above, the second floor frames 12c and 12g are installed on the upper surface side of the floor panel 11, but the floor structure of the vehicle body of the present invention is not limited to this form. is not.

That is, in the structure in which the second floor frames 12c and 12g are provided on the upper surface side of the floor panel 11 as in the modified examples 3 and 4, the second floor frame 12c is used.
Alternatively, the sub floor members 12a and 12b can be directly joined to each other by the second floor frame 12
In the structure in which c and 12g are installed on the lower surface side of the floor panel 11, the second floor frame 12c or 12g and both the sub cross members 12a and 12b may be joined with the floor panel 11 interposed therebetween.

In such a configuration, the flange of the second floor frame 12c or 12g and the floor panel 1
1 and the flanges of both sub-cross members 12a, 12b may be joined by hitting three sheets by spot welding, for example.

Also, the second floor frames 12c and 12g
Contrary to the structure in which is installed on the lower surface side of the floor panel 11,
As shown in FIG. 9, the entire floor frame 12 is installed on the upper surface of the floor panel 11, and the floor frame 12h installed on the upper surface allows the front and rear two rows of the cross members 1 to be installed.
It is also possible to adopt a structure in which the respective divided portions 13e of No. 3 are joined, and even with such a configuration, the same operation and effect as those of the above-described embodiment can be obtained.

[0092]

According to the floor structure of the vehicle body of the present invention, for example, even if the floor frame is displaced upward or downward with respect to the floor panel due to an impact load in the vehicle front-rear direction, Since the displacement independent structure formed on the cross member makes the displacement at the joint portion of the occupant seat coupled to the cross member independent of the displacement of the floor frame, the occupant is seated on the occupant seat. It is possible to reduce a change in restraint with respect to the occupant, which may be caused by the displacement of the occupant in the vertical direction.

Further, according to the floor structure of the vehicle body of the present invention as defined in claim 2, in addition to the effect according to claim 1, the displacement is suppressed more than displacement when the cross member is not divided, and the floor frame structure The displacement in the vertical direction can be suppressed, and the change in the restraint property for the occupant, which may be caused by the displacement in the vertical direction of the occupant seated on the occupant seat, can be reduced.

Moreover, in this displacement independent structure, since the cross member is simply divided at a predetermined position, it is possible to suppress an increase in manufacturing cost.

Further, according to the floor structure of the vehicle body of the present invention as defined in claim 3, in addition to the effect according to claim 2, the two adjacent cross members have mutually adjacent parts. Since the members are joined by the connecting member, it is possible to improve the strength against the load input from the side of the vehicle body, as compared with a cross member that is simply divided and divided into two parts.

Further, according to the floor structure for a vehicle body of claim 4 of the present invention, in addition to the effect according to the corresponding claim of claims 2 and 3, two cross members obtained by division are obtained. Since the adjacent parts are joined by a part of the floor frame installed on the upper surface of the floor panel, compared to a cross member that is simply divided and divided into two parts, from the side of the vehicle body The strength against the input load can be improved.

Further, as compared with the floor structure joined by the thin plate connecting member, since it is further joined by a part of the floor frame installed on the upper surface of the floor panel, the load applied from the side of the vehicle body The strength against it can be further improved.

Further, it is possible to avoid an increase in the number of members and suppress an increase in manufacturing cost.

According to the floor structure for a vehicle body of claim 5 of the present invention, in addition to the effects according to the corresponding claims of claims 1 to 4, a larger vertical direction generated on the rear side of the vehicle body Since the displacement is preferentially suppressed, it is possible to reduce a change in restraint with respect to the occupant, which may occur due to a vertical displacement of the occupant seated on the occupant seat.

According to the floor structure for a vehicle body of claim 6 of the present invention, in addition to the effects according to the corresponding claims of claims 1 to 5, the displacement independent structure is provided in the vertical direction of the floor frame. Even when the displacement of is not completely absorbed,
The occupant's seat is kept substantially horizontal in the width direction of the vehicle body,
The practically useful effect that the change in the restraint property in the vehicle width direction for the occupant seated on the occupant seat can be reduced is exhibited.

[Brief description of drawings]

FIG. 1 is a perspective view showing a floor structure of a vehicle body according to an embodiment of the present invention.

FIG. 2 is a perspective view showing details of the floor structure according to the embodiment.

FIG. 3 is a rear view of the seat corresponding to FIG. 12 in the floor structure of the embodiment.

FIG. 4 is a perspective view showing a floor structure of Modified Example 1.

FIG. 5 is a perspective view showing a floor structure of Modification 2;

FIG. 6 is a perspective view showing a floor structure of Modification 3;

7 is a cross-sectional view showing a cross section taken along the line BB in FIG.

FIG. 8 is a perspective view showing a floor structure of Modification 4;

FIG. 9 is a perspective view showing a modified example in which the entire floor frame is installed on a floor panel.

FIG. 10 is a perspective view showing a conventional floor structure of a vehicle body.

FIG. 11 is a schematic diagram showing deformation of the floor frame when an impact load is applied in the vehicle front-rear direction.

12 is a rear view of the seat as seen from the direction of arrow A in FIG.

[Explanation of symbols]

10 Car body floor structure 11 floor panels 11a tunnel section 11b slope 11c flange 12 floor frame 12a flange 12b First floor frame 12c Second floor frame 12d upper surface 12e Front end face 12f side 12g 2nd floor frame 12h floor frame 13 cross members 13a Sub cross member 13b Sub cross member 13c Seat mounting part (joint part) 13d flange 13e Divided part (displacement independent structure) 13f front 13g upper surface 13h flange 14 Connection plate 15 Bulkhead 20 seats (passenger seats) 21 base

Claims (6)

[Claims] 1. A floor panel of a vehicle body, a floor frame installed on the lower surface of the floor panel so as to extend in the front-back direction of the vehicle body, and the floor frame extending in the width direction of the vehicle body so as to intersect the floor frame. A floor structure of a vehicle body, which is installed on an upper surface of a panel and has a cross member to which a base portion of each occupant seat is joined, wherein vertical displacement of a joined portion of the occupant seat A floor structure for a vehicle body, wherein the cross member is formed with a displacement independent structure that is independent of vertical displacement in a portion intersecting with the cross member. 2. The floor structure for a vehicle body according to claim 1, wherein the displacement independent structure is a structure for dividing the cross member in a width direction at a portion intersecting with the floor frame. 3. The floor structure of a vehicle body according to claim 2, wherein adjacent portions of the divided cross members are joined together by a connecting member that is thinner than the cross member. . 4. At least part of the floor frame is installed on the upper surface of the floor panel, and adjacent parts of the divided cross members are part of the upper surface of the floor panel. The floor structure for a vehicle body according to claim 2 or 3, wherein the floor structure is joined by a floor frame. 5. The occupant seat base is formed in two rows in front of and behind the vehicle body, and the cross members are installed in two rows corresponding to the occupant seat base. Of the two rows of cross members, The vehicle floor structure according to any one of claims 1 to 4, wherein the displacement independent structure is formed on at least a cross member corresponding to the rear of the vehicle body. 6. The cross member extends from substantially the center of the floor panel to a side edge, and the intersecting portions are substantially central in the vehicle body width direction of the cross member and the vehicle body width direction of the occupant seat. 6. The substantially central portion, wherein a connecting portion between the cross member and the base portion of the occupant seat is arranged substantially symmetrically with respect to the intersecting portion. The floor structure of the vehicle body according to item 1.