Abstract:
The pillar structure to which the passenger cabin end of the hood ridge panel is connected, is arranged have different localized structural deformation resistances which buckle/deform in a manner which causes the hood ridge panel to reorient in response to a vehicle structure deforming force being applied to the front of the vehicle during a collision, and results in the force, which passes through the hood ridge panel, being redirected by a load-converting and transmitting member included in the pillar, up and along an upper rearwardly angled upper portion of the pillar. This force redirection produces sufficient resistance to induce compressive bucking in the structure forward of the passenger cabin and thus attenuate damage to the cabin structure.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates generally to an automotive body structure. More specifically, the present invention relates to the structure of a front pillar section of an automobile body that includes a reinforcement/structural deformation resistance control arrangement that achieves impact force re-direction and improvement in frontal impact safety.  
           [0003]    2. Description of the Related Art  
           [0004]    Japanese Unexamined Patent Publication (kokai) No. 10-7020 discloses an automotive body structure that is equipped with an arrangement for absorbing collision/impact energy. In this structure, the energy absorbing arrangement is located at the lower ends of each front pillar and at a level that is opposite each of the front wheels. With the arrangement, energy is absorbed in the event that the forward wheels are forced back under the impact to the degree that they deformingly engage the forward surfaces of the lower ends of the front pillars.  
           [0005]    In the above-mentioned structure, while it will be expected that this energy absorbing arrangement would contribute to impact energy absorption at the time of the interference with the front wheels and the other automotive front members. However, it may not contribute to the absorption of the impact energy before the front wheel contacts the lower pillar. Accordingly, there still exists a need for a structure that can improve the impact energy provided by the vehicle cabin in the event of a severe head-on collision or the like.  
         SUMMARY OF THE INVENTION  
         [0006]    It is an object of the present invention to provide a body structure for a vehicle that is capable of effectively inducing predetermined amounts of buckling (structural) deformation of the structural member(s) located immediately in front of the passenger compartment and which redirects the impact force through an upper portion of the front pillar in a manner that improves collision energy absorbing characteristics of the automotive vehicle.  
           [0007]    These and other objects of the invention are satisfied by an embodiment of the invention, which provides a body structure for a vehicle, comprising: a front pillar having a lower pillar portion and an upper pillar portion, the upper pillar portion merging with an upper end of the lower pillar, the upper pillar portion being angled toward a rear of the vehicle with respect to the lower pillar portion; a hood ridge member extending longitudinally along a side of the vehicle structure, the hood ridge member having a rear end portion joined to an upper end of the lower pillar portion; and a load-converting and force transmitting arrangement comprising: a first structural feature which forms part of the front pillar, the first structural feature being arranged to induce structural deformation of a predetermined portion of the lower front pillar portion upon a predetermined amount of force being transmitted thereto through the hood ridge member as a result of a frontal collision of the vehicle, the first structural feature re-orienting at least a rear end portion of the hood ridge member, with respect to the front pillar, to an orientation where the rear end portion of the hood ridge member is at least partially aligned with the angled upper pillar portion and so that force is transmitted from the hood ridge member toward the upper front pillar portion, and a second structural feature which forms part of at least one of the upper and lower pillar portions and which is arranged to receive force from the hood ridge member and to direct the received force along the upper front pillar portion. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    The various features and advantages of the embodiments of the present invention will become more clearly appreciated as a detailed description thereof is given with reference to the appended drawings wherein:  
         [0009]    [0009]FIG. 1 is a perspective view of a body structure for a vehicle to which the embodiments of the present invention are applicable;  
         [0010]    [0010]FIG. 2 is a perspective view depicting the essential body structural elements according to a first embodiment of the invention;  
         [0011]    [0011]FIG. 3 is a schematic side view of body structure, which demonstrates various aspects of the first embodiment of the invention;  
         [0012]    [0012]FIG. 4 is a sectional view taken along section line  4 - 4  of FIG. 3 showing structural deformation which occurs in accordance with the first embodiment;  
         [0013]    [0013]FIG. 5 is a perspective view of vehicular body structure showing the effect of the first embodiment and the initial type of deformation, which occurs as a result of a severe head-on type collision:  
         [0014]    [0014]FIG. 6 is a perspective view showing the deformation, which develops in accordance with the first embodiment during subsequent stages of vehicle deformation;  
         [0015]    [0015]FIG. 7 is a perspective view of a door hinge employed in the first embodiment of the invention;  
         [0016]    [0016]FIG. 8 is a perspective view showing a second embodiment of the invention;  
         [0017]    [0017]FIG. 9 is a schematic side view of the body structure showing zones of localized reduced structural strength and the provision of reinforcement member in accordance with a third embodiment of the invention;  
         [0018]    [0018]FIG. 10 is a perspective view of a reinforcement member used in the third embodiment of the invention; and  
         [0019]    [0019]FIG. 11 is a perspective view showing a further embodiment of the invention wherein a reinforcing portion is secured to one or both of the upper side of the hood ridge and upper pillar. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     First Embodiment  
       [0020]    In FIG. 1, reference numerals  1  designate left and right front pillars each of which comprises of a substantially-upright lower pillar portion  1 A and rearwardly obliquely angled upper pillar portion  1 B which merges with and upper end of the lower pillar portion  1 A.  
         [0021]    Hood ridge members  2  are provided on each lateral side of the illustrated automotive body. In this arrangement, the rear or inboard ends of each hood ridge member  2  is abutted against and welded to a front face of an upper end of a lower pillar portion  1 A.  
         [0022]    Reference numeral  3  denotes a dash cross member while  4  designates front side members which are respectively coupled a side of the dash cross member  3 . In order to strengthen the hood ridge members  2 , the dash cross member  3  and the front side members  4 , strut tower members  5  are respectively combined with these elements.  
         [0023]    The front ends of the left and right front side members  4  are connected with each other through a first cross member  6  and a bumper armature  7 . The front side members  4 , the first cross member  6 , the bumper armature  7 , the hood ridge members  2 , and the strut tower members  5  constitute the framework of a front compartment FC.  
         [0024]    The respective lower ends of the left and right lower pillars  1 A are joined to left and right side sills  9 , respectively. These side sills  9  constitute a floor framework and extend down both sides of a floor member  8 . The respective upper ends of the left and right upper pillars  1 B are joined to left and right side roof rails  12  and a front roof rail  13 . These elements  12 ,  13  constitute a roof framework of a roof panel  11 .  
         [0025]    In FIG. 1, reference numerals  14  denote center pillars,  15  one of the two rear pillars, and  16  one of the two rear fenders of the automotive body.  
         [0026]    In this embodiment, each front pillar  1  is, as best seen in FIG. 4, formed of a substantive outer member  1 OUT and an inner member lIN shown in two dot phantom. Both members of the pillar are each formed as single integral or unitary body via casting of a corrosion resistant lightweight material, such as an aluminum alloy. In FIG. 1, the front end of the side sill  9 , the front end of the side roof rail  12  and the lateral end of the front roof rail  13 , are hatched for ready identification.  
         [0027]    Additionally, as shown in FIGS. 2 and 3, each lower pillar  1 A is provided with a load-converting and transmitting member  21  which converts and transmits a front and rear direction&#39;s force that the hood ridge member  2  has been subjected at the vehicle&#39;s collision, into a force in the axial direction of the upper pillar  1 B.  
         [0028]    The load-converting and transmitting member  21  includes a load-receiving part  22  which is arranged to extend from a site where the upper end of the lower pillar  1 A to the hood ridge member  2  join, and which is inclined with respect to the lower pillar  1 A for receiving a longitudinally acting collision force in a manner which will be described in more detail hereinafter.  
         [0029]    A “weakened part” (viz., a portion or zone of relatively reduced structural deformation resistance)  23  (or first structural member) is provided forward and below the load-receiving part  22 , and a reinforcement part  24  which supports the load-receiving part  22 .  
         [0030]    The load-receiving part  22  in this embodiment includes a slanted or angled rib  22   a  that is integrally or unitarily formed with the lower pillar  1 A. The slanted or angled rib  22   a  has its upper edge joined to an upper wall of the hood ridge member  2  that is connected to the front pillar  1 . On the other hand, the reinforcement part  24  has a reinforcement rib  24   a,  which is unitarily formed with both sidewalls of lower pillar  1 A and upper pillar  1 B. Additionally, the reinforcement rib  24   a  is continuously formed so as to extend from the center of the back face of the slanted rib  22   a  into the interior of the upper pillar portion  1 B. In this way, the load-receiving part  22  and the reinforcement part  24  are respectively provided in the form of “rib” structures.  
         [0031]    As shown in FIG. 4, the weakened part  23  is provided by the local control of the wall thickness of the lower pillar  1 A. That is, according to this embodiment, the portion of the lower pillar which is located in front of the slanted rib  22   a  is formed so as to have a wall thickness which is less than that of the remaining upper portion of the lower pillar  1 A. In this manner the area of relatively reduced structural deformation resistance is provided through the reduced structural strength inherent with the reduced wall thickness. Further, at the lower end of the lower pillar  1 A, another (second) “weakened” part  31  is provided on the front or forward side of the pillar at a location opposite the front wheel  17 . Behind this weakened part  31 , another (second) load-receiving member  32  is formed for receiving the longitudinally acting collision force, while another (second) reinforcement part  33  is formed there behind for supporting the load-receiving part  32 . Note, these additional parts  31 ,  32 ,  33  are referred to the second weakened part  31 , the load-receiving part  32  and the reinforcement part  33  to distinguish the same from the corresponding parts  23 ,  22 ,  24 , located above.  
         [0032]    Similarly to the load-receiving part  22  (or second structural feature) and the reinforcement part  24  of the load-converting and transmitting member  21 , the load-receiving part  32  and the reinforcement part  33  which are located in the lower portion of the lower pillar  1 A, has “rib” structures unitarily formed with the lower pillar  1 A. For example, in the embodiment, the load-receiving part  32  has a vertical rib  32   a  that is formed integrally with the lower pillar  1 A and merges with the lateral and bottom wall surfaces (faces) thereof. Similarly, the reinforcement part  33  is also constituted by a reinforcement rib  33   a  that is formed integrally with the lower pillar  1 A and the side sill  9 . The reinforcement rib  33   a  is, as will become more evident hereinbelow, also configured span the respective side faces of the lower pillar  1 A and the side sill  9 , and to extend from the substantial center of the back face of the vertical rib  32   a  into the interior of the side sill  9 . The vertical rib  32   a  is, in this embodiment, arc-shaped so as to facilitate its surface-acceptance for the front wheel  17 .  
         [0033]    The reinforcement rib  33   a  comprises a first rib member  33   a,  which substantially horizontally connects the back face of the vertical rib  32   a  with a stepped shelf  9   a  formed on the side face of the side sill  9 , and a second obliquely angled rib  33   a   2  which intersects with the first rib  33   a   1  and also connects the back face of the vertical rib  32   a  with the bottom face of the side sill  9 .  
         [0034]    Although not shown in detail, the second weakened part  31  at the lower end of the lower pillar  1 A can be also be provided by controlling a localized portion of the wall thickness of the lower pillar  1 A, as similar to the previous weakened part  23 . For example, the forward wall of the portion of the lower pillar which is located in front of the vertical rib  32   a  is formed so as to have a wall thickness which less than that of adjacent wall portions and thus establish the so called weakened part  31 .  
         [0035]    The lowermost end of the slanted rib  22   a  of the load-converting and transmitting member  21  is continuously integrated with the uppermost end of the vertical rib  32   a  of the lower pillar  1 A through the intermediary of a vertically extending connecting rib  34  formed unitarily with the inner face of the lower pillar  1 A.  
         [0036]    Note, although the above ribs  22   a,    24   a,    32   a,    33   a,    34  have been described as being unitarily formed with the outer member  1 OUT, it will be noted that, as an alternative, the ribs can be unitarily formed with the inner member  1 IN if so desired.  
         [0037]    According to the above-mentioned embodiment, when the collision force which acts in the longitudinal fore-and-aft direction of the vehicle, acts on the hood ridge member  2  during a vehicular collision, the collision force is effectively re-oriented and transmitted from the lower pillar  1 A of the front pillar  1  to the inclined upper pillar  1 B by the load-converting and transmitting member  21 . The thus transmitted force is then dissipated into the roof framework members, i.e., the side roof rail  12  and the front roof rail  13 .  
         [0038]    Consequently, while maintaining the reactive force of the hood ridge member  2  against compressive crushing at a higher level, the hood ridge member  2  can be positively deformed in it buckling mode to accomplish the effective buckling deformation of the front compartment FC, thereby improving the collision energy absorbing characteristics of the vehicle.  
         [0039]    In more detail, when the longitudinally acting collision force acts on the hood ridge member  2 , the slanted or angled rib  22   a  having the load-receiving part  22  of the load-converting and transmitting member  21 , receives the collision force and, due to the disposition of the weakened part or zone  23  in front of the slanted rib  22   a,  induces deformation of this zone with the attendant reduction in resistance to forward motion of the lower portion of the hood ridge member  2 . Accordingly, in response the bucking of the weakened part  23 , the relative high structural deformation resistance which exist at the upper level of the hood ridge member  2  causes the hood ridge member  2  to pivot downwardly so that it becomes re-oriented and tends to become aligned with the upper pillar  1 B in the manner illustrated in FIG. 5. In this way, it is possible to achieve load transmission to the upper pillar  1 B effectively.  
         [0040]    Again, as shown in FIG. 6, even if the buckling deformation of the weakened part  23  permits the rear end of the member  2  to butt against the bottom of the slanted rib  22   a,  the load transmission to the side of the upper pillar  1 B is still maintained during the latter stages of hood ridge buckling deformation since the slanted or angled rib  22   a  is reinforced by the reinforcement rib  24   a.  Therefore, due to the controlled buckling deformation induced in the lower pillar  1 A through the provision of the weakened part  23 , it is possible to improve the collision energy absorbing characteristics of the vehicle due to the buckling deformation of the front compartment FC including the hood ridge member  2  and thus increase the amount of collision energy absorbed.  
         [0041]    Above all, since the reinforcement rib  24   a  is formed integrally with the upper pillar  1 B from the back face of the slanted rib  22   a  to the inside of the upper pillar  1 B in addition to the integral casting of the lower pillar  1 A with the upper pillar  1 B, it is possible to remarkably enhance the efficiency of load transmission in the axial direction of the upper pillar  1 B.  
         [0042]    Additionally, the slanted or angled rib  22   a  has an upper end or edge joined to the upper wall of the hood ridge member  2 . Thus, if the strut tower  5  is subjected to an upwardly acting thrust or force, it is possible to maintain the resistance of the strut tower  5  to such a force due to the tensile strength of the slanted rib  22   a.    
         [0043]    With the provision of the second lower weakened part  31 , wherein the vertical rib  32   a  acts in the same manner as the load-receiving part  32  and the reinforcement rib  33   a  acts in the same manner as the reinforcement part  33 , when the buckling deformation of the front compartment FC progress to the degree that the front wheel  17  engages and interferes with the lower end of the lower pillar  1 A, collision energy can be further absorbed by the buckling deformation thereof, in the manner depicted in FIGS. 5 and 6.  
         [0044]    It is to be furthermore noted that the buckling deformation of the weakened part  31  is restricted by the vertical rib  32   a,  as shown in FIG. 6. That is to say, when the wall structure which defines the weakened part  31  is forced back into contact with the vertical rib  32   a  by tire impact, the longitudinally acting force is received by the rib  32   a  and is then transmitted into the side sill  9  thus reducing the load bearing burden on the lower pillar  1 A.  
         [0045]    Since the reinforcement rib  33   a  is formed integrally with the lower pillar  1 A and extends from the back face of the vertical rib  32   a  into the interior of the side sill  9 , in addition to integral casting of the lower pillar  1 A and the side sill  9  as a single body, the connecting rigidity between the lower pillar  1 A with the side sill  9  is enhanced.  
         [0046]    Additionally, the reinforcement rib  33   a  comprises a first substantially horizontal rib  33   a   1  which is connected with a shelf section  9   a  formed on the side face of the side sill  9 , and thus exhibits a high surface rigidity, and the second rib  33   a   2  which is connected with the back face of the side sill  9  while obliquely intersecting with the first rib  33   a   1  in order to distribute the load into the side face and the bottom face of the side sill  9 . Accordingly, it is possible to remarkably enhance the load transmissibility from the lower pillar  1 B to the side sill  9 .  
         [0047]    Further, since the slanted/angled rib  22   a  located at the upper end of the lower pillar  1 A is connected with the vertical rib  32   a  at the lower end of the lower pillar  1 A through the connecting rib  34  formed integrally with the lower pillar  1 A, the load transmissibility in the vertical direction of the lower pillar  1 A is improved to enhance the load transmissibility to the upper pillar  1 B and the side sill  9  even further.  
         [0048]    The above-mentioned lower pillar  1 A is equipped with door hinges of the type illustrated in FIG. 7. These door hinges  35  are fastened to upper and lower points on an outboard side face of the lower pillar  1 A through respective mounts or seat parts  36 . However, if the door hinges  35  are fastened in a manner wherein their seat parts  36  are located at the same level as, and/or overlap either of the weakened parts or zones  23 ,  31 , a problem may arise in that the “positive” (viz., controlled) requisite buckling deformation of the parts  23 ,  31  is modified by the existence of the seat parts  36 . In this embodiment however, each door hinge  35  is provided, between front and rear fastening holes  37 ,  37 , with an elongate hole  38  or the like. This feature reduces the structural reinforcing effect of the portion of the door hinge  35  (viz., the seat  38 ), and obviates the problem wherein the desired deformation of the “weakened” parts  23 ,  31  is inhibited.  
         [0049]    Further, the weakened parts  23 ,  31  of this embodiment are respectively established by controlling the wall thickness of the lower pillar  1 A and the load-receiving parts  22 ,  32  and the reinforcement parts  24 ,  33  are together provided in the form of “rib” structures. Therefore, these elements can be easily formed by means of casting and additionally, the distribution of plate/wall thickness and the rigidity of ribs can be adjusted to exhibit optimum characteristics through the control of wall thickness while taking advantage of the ease with which the products are cast.  
         [0050]    Since the lower pillar  1 A and the upper pillar  1 B are cast into one body including the load-receiving parts  22 ,  32 , the reinforcement parts  24 ,  33  and so on, it is possible to reduce the number of components, realizing the rationalization of vehicle body.  
       Second Embodiment  
       [0051]    [0051]FIG. 8 shows the second embodiment of the present invention. According to this embodiment, the reinforcement part  24  of the load-converting and transmitting member  21  is formed as a separate a reinforcement plate  24   b  which is connected to essentially the center of the rear face of the slanted or angled rib  22   a,  and arranged to extend back through the interior of the upper pillar  1 B. The reinforcement plate  24   b  is secured in place by means of welding, bonding, etc.  
         [0052]    Therefore, according to the second embodiment, it is possible to achieve essentially the same collision energy absorbing characteristics as the first embodiment. Additionally, owing to the provision of the reinforcement plate  24   b  which is separate (viz., not unitarily formed) from the upper pillar  1 B, it is possible to achieve an increase in the freedom of design with respect to the front pillar  1  and the reinforcement part  24 . Of course, by controlling both profile and thickness of flanges  24   c  and a bead  24   d  of the plate  24   b  in a suitable manner, it is also possible to control the characteristics of the reinforcement part  24  in terms of its reaction generating effect (viz., its force resisting/directing effect).  
       Third Embodiment  
       [0053]    [0053]FIGS. 9 and 10 show a third embodiment of the invention. According to this embodiment, the angled rib  22   a  of the load-converting and transmitting member  21  is arranged so as to extend from a junction of the upper wall of the hood ridge member  2  and the front pillar  1  to the rear face or wall of the lower pillar  1 A. A reinforcement part or portion  24  is defined by a thickened wall portion  24   c  which is either integrally formed on, or secured to, a portion of the rear wall of the lower pillar  1 A to which the slanted rib  22   a  is integrated.  
         [0054]    According to this embodiment of the invention, a reinforcement member  39  is additionally disposed in the lower pillar intermediate of the upper end which is connected to the hood ridge member  2  and the lower end which is connected to the side sill  9 . The provision of the reinforcement member  39 , renders it possible to provide both areas of the lower pillar portion which are faced by the slanted or angled rib  22   a  and the vertical rib  32   a  (shown by vertical hatching in FIG. 9), with lower relative levels of structural rigidity as compared with that portion which exhibits enhanced structural rigidity due to the provision of the reinforcement member  39 . This, in effect, allows these portions to undergo initial deformation and thus provides the weakened parts  23 ,  31  of the previous embodiments without actually reducing the structural strength of the two zones.  
         [0055]    As shown in FIG. 10, the reinforcement member  39  is shaped so as to have a substantially V-shaped configuration. The member  39  has an abutment surface  39   a  formed at the apex of the V-shaped member and flanges  39   b,    39   c  formed on the upper and lower terminal ends. The abutment surface  39   a  is welded to the front face of the lower pillar  1 A. The upper flange  39   b  of the member  39  is welded to the base of the thickened part  24   c  connected to the slanted rib  22   a,  while the lower flange  39   c  is welded to the upper end of the vertical rib  32   a.    
         [0056]    Therefore, also in this embodiment, it is possible to effect the similar characteristics of absorbing the collision energy to that of the first embodiment. Furthermore, since the slanted or angled rib  22   a  is arranged so as to extend from the upper wall of the hood ridge member  2  to the rear face of the lower pillar  1 A in the junction zone between the lower pillar  1 A and the upper pillar  1 B, the rigidity of integration therebetween can be enhanced to improve the transmissibility of load from the hood ridge member  2  to the upper pillar  1 B.  
         [0057]    In addition, since the reinforcement part  24  is constituted by the thickened part  24   c  on the rear face of the lower pillar  1 A, it is possible to establish the appropriate distribution of plate thickness owing to the characteristics of casting products.  
         [0058]    Further, since the weakened parts (viz., the areas of relatively lower structural deformation resistance)  23 ,  31  are established by the addition of the reinforcement member  39 , the overall rigidity of the pillar can be enhanced as compared with the previously described embodiments wherein both weakened parts are provided through the use of wall structures wherein the thickness of the walls are deliberately reduced to lower the strength thereof.  
         [0059]    Additionally, since the reinforcement member  39  connects the slanted rib  22   a  with the vertical rib  32   a  in this embodiment, the reinforcement member  39  provides the same function as the connecting rib  34  of the first embodiment, whereby it is possible to enhance the load-transmission performance of the lower pillar  1 A in the vertical direction of the vehicle.  
       Fourth Embodiment  
       [0060]    [0060]FIG. 11 shows a fourth embodiment of the invention. This arrangement, similar to the third embodiment, establishes a location of increased structural strength which automatically renders other portions relatively lower in resistance to structural deformation and thus achieves the same effect as the previously described embodiments. To increase the strength of the lower portion of the upper pillar portion  1 B and/or an upper end portion of the hood ridge member  2 , a reinforcement member or gusset  40  is welded or otherwise secured to an inboard edge of these two members in the manner shown in FIG. 11. This gusset  40  in this embodiment is located along and edge of the upper pillar  1 B. In addition, another reinforcement member or gusset  41  is secured to an inboard edge of the lower pillar  1 A.  
         [0061]    The gusset  41  is attached to the upper part of the front pillar and gusset  41  is attached to the lower part of the front pillar. The gussets  40 ,  41  form more rigid portions, which have a relatively higher rigidity, in the front pillar and center part C. A weakened portion is thus formed between the high rigidity portions. Because gussets  40 ,  41  are attached to the outer panel of the front pillar, the body structure is constructed rather easily. Moreover, the rigidity is readily adjustable due to the gussets  40 ,  41  being attached to the outer panel of the front pillar.  
         [0062]    Japanese Patent Application No. 2000-66478 upon which this application is based and on which the claim to priority is founded, is incorporated herein by reference thereto.  
         [0063]    Although the invention has been described above with reference to only a limited number of embodiments, the invention is not limited thereto and the various modifications and changes which can be made without departing from the scope of the invention will be self-evident to those skilled in the art to which the invention pertains.