Front body structure for vehicle

A front body structure is provided to restrain a collision load, which has been applied on a front wheel by a vehicle front collision, to be concentrated on a front end of a side sill excessively. In the structure, a front energy absorbing member 23 is attached to a back face of a lateral end of a bumper 21. A recess 18 is formed by a front end of the side sill 7 and a front face of an outrigger 15. A rear energy absorbing member 19 is attached into the recess 18. The outrigger 15 connects the side sill 7 with a front side member extension 5 joined to the rear end of a front side member 3. At the vehicle front collision, the front energy absorbing member 23 interferes with the right-and-front part of the front wheel 1 to allow the left-and-front part of the front wheel 1 to interfere with the side face of the front side member 3 and also allow the rear part of the wheel 1 to interfere with the rear energy absorbing member 19.

TECHNICAL FIELD

The present invention relates to a front body structure for vehicle.

BACKGROUND ART

Japanese Patent Publication (kokai) No. 11-342869 discloses a front body structure for vehicle. This front body structure includes a pair of side sills arranged on both sides of a lower part of a vehicle body to extend in the vehicle's fore-and-aft direction. Further, a front pillar is arranged to stand on a front end of each side sill. The front body structure is adapted so as to disperse a collision load, which has been transmitted through the front wheel at the vehicle front collision, by the side sill itself.

In the above-mentioned front body structure, however, there is a tendency that when the vehicle has a front collision, at least one front wheel interferes with only the front end of the side sill directly, so that a collision load is concentrated on the side sill excessively, causing its great deformation. Additionally, when the front wheel is steered inwardly in the vehicle's width direction since the vehicle has a collision from oblique forward, a problem arises in that the front wheel cannot always interfere with any vehicle-body structural member disposed inside the front wheel, for example, a side member. Such a subject is caused since the above front body structure is not controlled a traverse of the front wheel(s) subsequent to the vehicle collision.

DISCLOSURE OF INVENTION

Under the above circumstance, it is an object of the present invention to provide a front body structure which is capable of avoiding a concentration of a collision load, which has been exerted to a front wheel (or front wheels) by the vehicle front collision, on the front end of the side sill.

According to the present invention, the above-mentioned object is accomplished by a front body structure for vehicle, comprising;a front wheel arranged in each side of the vehicle;a vehicle-body structural member arranged at least behind the front wheel in a vehicle's fore-and-aft direction or inside the front wheels in a vehicle's width direction; anda front-wheel traverse controller provided on the vehicle-body structural member, for controlling the traverse of the front wheel at a vehicle front collision and transmitting a collision load from the front wheel to the vehicle-body structural member.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring to accompanying drawings, embodiments of the present invention will be described below.

In the figures,FIG. 1is a plan view of a front structure of a vehicle body in accordance with the first embodiment of the invention.FIG. 2is a perspective view ofFIG. 1, whileFIG. 3is a perspective view of an automobile equipped with the front structure of FIG.1. In common withFIGS. 1 and 2, a direction shown with an arrow Fr designates a front side of the vehicle body. Note,FIGS. 1 and 2only show the front structure on the right side of the vehicle body; nevertheless the front structure on the left side of the vehicle body is identical to the same on the right side of the vehicle body because of its symmetrical arrangement. Therefore, the following descriptions will be represented by an example of the front structure on the right side of the vehicle body.

Inside a front wheel1in the vehicle width direction, there is a front side member3(as the vehicle-body structural member) extending in the fore-and-aft direction of the vehicle body. The front side member3has its rear end joined to an extension5of the front side member3, which will be referred—front side member extension5—, hereinafter. Behind the front wheel1, a side sill7(as the vehicle-body structural member) is arranged to extend in the fore-and-aft direction of the vehicle body. On the top of a front end of the side sill7, a front pillar9stands so as to cover the front end of the side sill7.

A floor panel11is arranged inside the side sill7. A dash panel13is arranged on a front end of the floor panel11. The dash panel13is also provided, at a lower end thereof, with a dash-lower cross member17. The above front side member extension5is welded to an under face of the floor panel11, passing around a lower part of the dash-lower cross member17. As shown inFIG. 1, the front side member extension5is connected to the front end of the side sill7through an outrigger15.

In the embodiment, the above front side member3, the front side member extension5, the side sill7, the outrigger15and the dash-lower cross member17correspond to “vehicle-body” structural members that form a framework for the vehicle body.

On the side of the side sill7, the outrigger15has one end closer to the vehicle's rear than the outrigger's other end on the side of the front side member extension5, providing a slanted face15a(guide part) which is inclined toward the vehicle's rear as shifting outward in the vehicle width direction. The front end of the side sill7is shaped with an outside face (in the vehicle width direction) projecting toward the vehicle's front, providing a projecting part (projecting portion)7a.Therefore, the front end of the side sill7is provided with a slanted face7bwhich is inclined toward the vehicle's rear as shifting inwardly in the vehicle width direction. In the vehicle width direction, the outside face of the projecting part7ais positioned outside the outer face of the front wheel1when traveling straight.

A rear energy absorbing member19of hard urethane foam is fitted to a recess18defined by the slanted face15aof the outrigger15and the slanted face7bof the side sill7.

A bumper21(one of the “vehicle body” structural members) is attached to the front end of the front side member3. A front energy absorbing member23of hard urethane foam is fitted to the rear face of the bumper21, at its outer end in the vehicle width direction. As similar to the rear energy absorbing member19, the outside face (in the vehicle width direction) of the front energy absorbing member23is positioned outside the outer face of the front wheel1when traveling straight. The front energy absorbing member23is shaped with an outside face (in the vehicle width direction) projecting toward the vehicle's rear, providing a projecting part23afor covering the outer part of the front wheel1.

In the embodiment, all of the slanted face15a,the outrigger15, the slanted face7bof the side sill7and the front/rear energy absorbing members19,23form a front-wheels' traverse controller of the invention. A subframe29is fitted on both under faces of the front side member3and the front side member extension5. The subframe29is provided with a suspension arm25linked to the front wheel1at a joint27. Between the under face of the front side member3and the under face of the dash-lower cross member17, the subframe29is provided with the bending parts (see FIG.8A).

The front end of the subframe29is fastened to the under face of the front side member3at a front fastening part31, while the rear end of the subframe29is fastened to the under face of the front side member extension5at a rear fastening part33. The subframe29is provided, on its corner at the rear fastening part33, with a brace member35.

The subframe29includes a front slanted part29ainclining from the front fastening part31toward the vehicle's rear downward, a horizontal part29bextending from the rear end of the part29atoward the vehicle's rear horizontally and a rear slanted part29cinclining from the rear end of the part29btoward the rear fastening part33somewhat upward. The suspension arm25is connected to the horizontal part29b.

The above-mentioned front structure operates as follows.FIG. 4shows a situation where an automobile having the above front structure has a front collision with an opponent vehicle35obliquely from front on the right side. Then, an oblique load F is applied on the front face of the bumper21on its right side.FIG. 5illustrates the sequential traverse of the front wheel1and the sequential deformation of respective vehicle parts, with partial diagrams (a) to (f).

First, when the load F is applied to the bumper21obliquely from front on the right side, the right end of the bumper21begins to be deformed with internal folding, as shown in the partial diagram (a). With this internal folding, the front energy absorbing member23on the back of the bumper21interferes with the front-and-right part of the wheel1. Successively, the front energy absorbing member23is deformed to produce a load F1allowing the wheel1to retreat and another load F2allowing the wheel1to be steered (deformed) inwardly.

Then, the front energy absorbing member23operates to moderate an impact at the interference of the bumper21with the front wheel1, thereby preventing the bumper21from being folded locally. Additionally, since the deformation of the member23allows its contact area with the wheel1to be increased, it is possible to improve an efficiency to transmit the load from the bumper21to the front wheel1, permitting the reliable control in the traverse of the front wheel1to steer inwardly.

Further, since the front energy absorbing member23includes the projecting part23acovering the front wheel1and also the outside face (in the vehicle's width direction) positioned outside the outer face of the front wheel1, the member23guides the front wheel1so as to steer inwardly, ensuring the wheel's traverse control.

Next, as shown with the diagram (b) ofFIG. 5, the front wheel1interferes with the side wall of the front side member3due to the inwardly steering of the front wheel1, so that a lateral load is applied on the front side member3.

Simultaneously with the situation shown with the diagram (b), the deformation of the vehicle body progresses with the application of an oblique load from the opponent vehicle35to the front ends of the front side member23and the subframe29. Consequently, as shown with two-dot chain lines in the diagram (d) in side view, the subframe29is folded downward. Simultaneously, due to the additional application of the lateral load, the subframe29is further deformed inwardly (left side ofFIG. 5) together with energy absorption by the deformation of the brace member35.

As a result of the above traverse of the subframe29, the suspension arm25is shifted inwardly while moving backward. Then, the front wheel1is of the same traverse. Thereafter, due to an additional load applied on the inward-steered front wheel1, it further moves backward to interfere with the rear energy absorbing member19mounted on both front ends of the side sill7and the outrigger15, as shown in the diagram (f). Owing to this deformation of the rear energy absorbing member19, it is possible to effect the energy absorption at the vehicle front collision.

Subsequently, when the deformation of the vehicle body progresses together with the deformation of the rear energy absorbing member19, the rear end of the front wheel1is guided, at its inside corner, into the recess18defined by the slanted face7bof the side sill7and the slanted face15aof the outrigger15, so that the front wheel1has a steering posture shown in FIG.4.

Again, the outside face of the projecting part7aof the side sill7is positioned outside the outer face of the front wheel1in the vehicle's width direction. Thus, when the front wheel1moves back at the vehicle front collision, it is possible to prevent the front wheel1from being forced out of the side sill7and also possible to transmit the collision load to the front side member3and the side sill7certainly.

As mentioned above, owing to the accomplishment of the situation (a), it is possible to control the traverse of the front wheel1in the steering direction before the rear end of the front wheel1comes in contact with the rear energy absorbing member19, thereby allowing the rear end of the front wheel1to be guided by the recess18with ease.

Further, owing to the accomplishment of the situation (b), since the front wheel1interferes with the front side member3at a designated position before the member3is folded inwardly and greatly, it is possible to ensure a route to transmit a load from the front wheel1to the front side member3.

Additionally, owing to the accomplishment of the situations (c) and (d), the front wheel1is displaced backward by both of the downward-folding of the subframe19and the front input while maintaining a substantial constant steering angle as a result of that the front wheel1has its left-and-front end guided by the sidewall of the front side member3.

Subsequently, owing to the accomplishment of the situation (f), the position (in the vehicle's width direction) of the front wheel1is controlled by the guidance of the recess18at its substantial center while the impact energy at the vehicle front collision is absorbed by the rear energy absorbing member19. Consequently, it is possible to transmit the collision load on the front wheel1to the outrigger15and the side sill7certainly.

As to the whole effect brought by the above-mentioned traverse of the front wheel1, the load applied on the vehicle obliquely from front can be received by the front wheel1from the beginning of the collision and furthermore, it is possible to efficiently transmit the load from the front wheel1to the vehicle-body structural members forming a body framework, for example, the front side member3, the side sill7, the outrigger15, etc. Consequently, without greatly deforming elements forming a vehicle cabin space, such as the front pillar9and the side sill7, it is possible to perform the energy absorption at the vehicle front collision efficiently.

FIGS. 6A and 6Billustrate the situations at the vehicle collision in side view. As shown inFIG. 6A, when an oblique load F is applied on the front wheel1from the vehicle's front, the front wheel1moves back with the above-mentioned steering movement, so that the wheel1interferes with the rear energy absorbing member19with the deformation of a rubber part of the wheel1, as shown in FIG.6B. Owing to this deformation of the rear energy absorbing member19, the impact energy is absorbed.

Since the collision load inputted to the front wheel1is transmitted to the front end of the side sill7and the outrigger15through the rear end of the wheel1, the great deformation is not exerted on the front pillar9having door hinges37,39attached thereto directly, thereby facilitating the opening/closing of the doors even after the collision.

As shown inFIGS. 7,8A and8B, when the vehicle collides with the opponent vehicle straightforwardly, a load F in the vehicle's fore-and-aft direction is exerted throughout the whole bumper21. Therefore, the front side member3and the subframe29are subjected to a collision load in the vehicle's fore-and-aft direction from the beginning of collision.

Consequently, as shown inFIGS. 7 and 8B, the bumper21is compressively deformed as a whole and simultaneously, the front side member3is axially deformed in compression and the subframe29is folded downward. Then, the front energy absorbing member23on the bumper21interferes with the front part of the front wheel1to start the deformation of the rubber part of the front wheel1and its retreat. Further, with the progress in the retreat of the front wheel1, the rear end of the front wheel1interferes with the rear energy absorbing member19arranged on the side sill7and the outrigger15. In this way, owing to the deformation of the rear energy absorbing member19, it is possible to increase an amount of energy to be absorbed.

According to this embodiment, the outside face (in the vehicle's width direction) of the projecting part7aat the front end of the side sill7is positioned outside the front wheel1. Therefore, when the retreat of the front wheel1at the vehicle front collision causes the rear energy absorbing member19to be deformed, the wheel's traverse is controlled by the projecting part7athereby to prevent the side sill7from projecting outward.

That is, according to the embodiment, even when the vehicle collides with the opponent vehicle35not only obliquely but also straightforwardly so that the front wheel1retreats simply, the front wheel1is guided by the recess18formed by the projecting part7aof the side sill7and the outrigger15. Consequently, the front end of the front wheel1interferes with the front side member3, while the rear end of the wheel1interferes with the front end of the side sill7and the outrigger15through the rear energy absorbing member19, whereby the collision load from the front wheel1can be dispersed to the vehicle-body structural members forming the framework for vehicle-body, efficiently.

In place of the projecting part23a,the front energy absorbing member23may be formed so that its rear surface inclines toward the vehicle's rear side as shifting outward in the vehicle's width direction. Alternatively, instead of the inclined rear face of the member23, the bumper21may be formed with a rear surface facing the front wheel1, which is inclined in the above manner. In a further modification, as shown inFIG. 9, the bumper21may be formed so that its end projects toward the vehicle's rear thereby to cover the front wheel1.

In the above-mentioned embodiment, all of the lateral end (in the vehicle's width direction) of the bumper21, the front energy absorbing member23, the recess18in front of the side sill7and the outrigger15, and the rear energy absorbing member19form a front-wheel traverse controller which controls the traverse of the front wheel1and further transmits the collision load from the front wheel1to the vehicle-body structural members when the vehicle has a front collision.

FIGS. 10A and 10Billustrate the second embodiment of the present invention. According to this embodiment, there is provided, at a position of the section X—X of the front pillar9ofFIG. 6, a plate member41(as external reinforcing member) between a “front pillar” lower-and-outer member9aand the rear energy absorbing member19. In the figures, reference numeral9bdenotes a “front pillar” lower-and-inner member.

Corresponding to the front pillar9, the rear energy absorbing member19is shaped so as to have a notch face19aallowing a triangular space43to be defined between the member19and the “front pillar” lower-and-outer member9a.The above plate member41is arranged so as to cover the notch face19a.The plate member41has one end welded to the “front pillar” lower-and-outer member9aat its connection with the “front pillar” lower-and-inner member9band also has the other end welded to an inner face of a panel member45.

Therefore, according to the second embodiment, even when the front collision load is applied to the rear energy absorbing member19through the front wheel1, the deformation on so-called “body's side part” (e.g. the “front pillar” lower-and-outer member9aforming a cabin space) can be reduced by the plate member41, whereby it is possible to ensure the deformation-prevention of the door hinges39,37.

FIGS. 11A and 11Bshow the third embodiment of the invention. According to the embodiment, the triangular space43of the second embodiment is replaced with a rectangular space which is filled up with a filling member47made of resin or light metals. Then, in addition to the similar effects of the second embodiment, it is possible to efficiently reinforce the front body structure since the filling member47can be accommodated in the rectangular space with ease.

FIGS. 12A and 12Bshow the fourth embodiment of the invention. According to the embodiment, the rear energy absorbing member19in front of the side sill7is formed in such a manner that the same member's thickness in the vehicle's fore-and-aft direction gradually increases as directing from the member's upper part corresponding to the front pillar9to the member's lower part corresponding to the side sill7.

As shown inFIG. 12B, at the vehicle front collision, the rear energy absorbing member19is apt to be deformed mainly at the member's lower part corresponding to the side sill7. Therefore, by increasing the thickness of the member's lower part, the collision load on the front wheel1can be transmitted as an axial force to the side sill7mainly, whereby it is possible to reduce a load on the front pillar9and also a bending moment generating in the base of the front pillar9.

FIGS. 13A and 13Bshow the fifth embodiment of the present invention. According to the embodiment, the “hollow” front side member3is provided with a recessed reinforcement49for acceptance of the front part of the front wheel1being deformed at the vehicle front collision. The reinforcement49is fitted on an inside face of the member's outside portion in the vehicle's width direction. Consequently, at the collision, the front wheel1interferes with the recessed reinforcement49after the sidewall of the front side member3has been deformed by the front-and-left corner of the front wheel1, as shown in FIG.13B. Thus, the collision load applied on the front wheel1can be converted into a force on the front side member3in the fore-and-aft direction through the reinforcement49, whereby it is possible to improve an efficiency to transmit a load to the vehicle-body structural members forming the framework of vehicle body.

FIG. 14shows the sixth embodiment of the present invention. According to the embodiment, the rear energy absorbing member19has its side facing the front wheel1, formed so as to correspond to a steering locus (tracks of traverse) of the front wheel1moving at the vehicle front collision. In other words, corresponding to the profile of the recess18defined by the slanted face7bof the side sill7and the slanted face15aof the outrigger15, the rear energy absorbing member19is shaped so as to have a generally-uniform thickness in the vehicle fore-and-aft direction.

Owing to the formation of the rear energy absorbing member19, even if the steering angle of the front wheel1at the vehicle front collision varies slightly, it is possible to ensure the energy absorption of collision load exerted to the front wheel1sufficiently.

FIG. 15shows the seventh embodiment of the present invention. According to the embodiment, a projecting member51in place of the above projecting part7ais fitted to the front end of the side sill7. Owing to the provision of the member51different from the side sill7, by altering the member51to another member so as to accord with the modifications in both vehicle sorts and the front wheel's shape appropriately, it is possible to prevent the front wheel1from projecting outward in the vehicle's width direction while treating in contact with the front end of the side sill7, without altering the frame structure for vehicle body greatly.

FIGS. 16A and 16Bshow the eighth embodiment of the present invention. According to the embodiment, the “hollow” front pillar9is provided, at a position of the section XVI—XVI of the front pillar9ofFIG. 6A, with a plate member53as an internal reinforcement. The plate member53has one end welded to the inner face of the “front pillar” lower-and-outer member9aand the other end welded to a joint between the member9aand the “front pillar” lower-and-inner member9b,thereby forming a space55between the front part of the member9aand the plate member53.

In this way, as shown inFIG. 16B, since the space55operates to absorb the front collision load, it is possible to prevent the deformation of the front pillar9in the vicinity of the door hinge37.

Japanese patent application No. 2001-52736 is expressly incorporated herein by reference.

The scope of the invention is defined with reference to the following claims.

Industrial Applicability

A front body structure is provided to restrain a collision load, which has been applied on a front wheel by a vehicle front collision, to be concentrated on a front end of a side sill excessively. This front body structure is capable of avoiding a concentration of a collision load, which has been exerted to a front wheel (or front wheels) by the vehicle front collision, on the front end of the side sill.