Abstract:
A vehicle front body structure including a front end module attached to a body front end. The front end module includes a frame member and a headlamp unit supported on the frame member. The headlamp unit is provided with a mounting device which is configured to flexibly support the headlamp unit on the frame member, and to provide a tendency to move the headlamp unit to its attachment position, upon application of a force exceeding a predetermined threshold to the headlamp unit.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a vehicle front body structure, particularly to a structure for obtaining a uniform gap of a predetermined size between a headlamp unit of a front end module and a front fender at assembly. 
   2. Description of Related Art 
   In vehicle body manufacturing process, a front end module including a radiator support and headlamp units and the like mounted thereon is sub-assembled in a sub-assembly line, and fed to a main assembly line to be mounted on to a body flowing therethrough. In this mounting process, a gap between the headlamp unit of the front end module and a front fender of the body is adjusted to a predetermined size. 
   Japanese Patent Application Laid-Open Publication No. 2003-267123 discloses a mounting structure of a headlamp unit allowing a screw adjustment of a gap between the headlamp unit and a front fender, providing inclined slidable contact faces on a projected portion of the headlamp unit housing and on an attachment portion of a radiator support. 
   SUMMARY OF THE INVENTION 
   However, in the mounting structure described above, it is difficult to obtain a uniform and constant gap between the headlamp unit and the front fender. If fastening torque of the screw is too large, the headlamp unit becomes so close to the front fender that the headlamp unit may interfere with the front fender. Meanwhile, if the fastening torque of the screw is too small, the gap between the headlamp unit and the front fender may become too large. 
   It is an object of the present invention to provide a vehicle front body structure which enables to obtain a uniform gap of a predetermined size between the headlamp unit and the front fender, and provides an easy mounting of the headlamp unit. 
   An aspect of the present invention is a vehicle front body structure comprising a front end module attached to a body front end, the front end module including a frame member and a headlamp unit supported on the frame member, wherein the headlamp unit is provided with a mounting device which is configured to flexibly support the headlamp unit on the frame member, and to provide a tendency to move the headlamp unit to its attachment position, upon application of a force exceeding a predetermined threshold to the headlamp unit. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described with reference to the accompanying drawings wherein: 
       FIG. 1  is an exploded perspective view of a vehicle front body structure according to an embodiment of the present invention. 
       FIG. 2  is a perspective view of the vehicle body front structure according to the embodiment of the present invention, viewed from obliquely above, in which a front end module is bolt-fastened to a hood ledge member, and a headlamp unit is temporarily supported on a frame member of the front end module. 
       FIG. 3  is an enlarged cross-sectional view of an attachment portion of the headlamp unit taken along a line III-III of  FIG. 2 . 
       FIG. 4  is an enlarged cross-sectional view of the attachment portion of the headlamp unit, showing a state where the headlamp unit is being moved rearward relative to the front end module. 
       FIG. 5  is an enlarged cross-sectional view of the attachment portion of the headlamp unit, showing a state where the headlamp unit has moved to an attachment position thereof. 
       FIG. 6  is an enlarged cross-sectional view showing a state where the headlamp is fastened to the frame member of the front end module with a bolt. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   An embodiment of the present invention will be explained below with reference to the drawings, wherein like members are designated by like reference characters. 
   As shown in  FIG. 1 , a front end module  1  to which a headlamp unit  5  is mounted on is connected to a hood ledge member  3  and a front fender  7  in a body front end. 
   The front end module  1  includes a radiator support  9  extending in a vehicle transverse direction as a frame member of the front end module, and a pair of headlamp units  5  supported on both of the transversely outer sides of the radiator support  9 . This radiator support  9  constitutes a structural frame member of the body front end. The radiator support  9  has an upper rail  11  extending in the vehicle transverse direction on an upper portion thereof, and on a lower portion thereof, an armature portion  17  substantially parallel to the upper rail  11 . These upper rail  11  and armature portion  17  are connected with each other by vertical hood lock stays  19  therebetween. 
   On each of the transversely outer sides of the front end module  1 , an upper attachment piece  21  is extended rearward from an upper end thereof, and a lower attachment block  23  is extended rearward from a lower end thereof. Bolt holes  25  and  27  are provided through the upper attachment piece  21  and lower attachment block  23 , respectively. As shown in  FIGS. 1 and 2 , the upper attachment piece  21  is put on an upper face of the hood ledge member  3  and fastened thereto with bolts  29  inserted through the bolt holes  25 , and the lower attachment block  23  is placed on a lower front end of the front fender  7  and fastened thereto with bolts  31  inserted through the bolt holes  27 . The front end module  1  is thus mounted on to the vehicle body. In this state, the headlamp unit  5  is supported in a position in front of the front fender  7 , with a gap of a predetermined size δ 1  provided between the front fender  7  and headlamp unit  5 . 
   Moreover, as shown in  FIGS. 2 and 3 , the headlamp unit  5  is flexibly supported on the front end module  1  by a support piece  15  and an elastic member  41 , which collectively constitute a mounting device  13 , provided on a rear side of the headlamp unit  5 . 
   The support piece  15  is extended rearward from a rear side of the headlamp unit  5 . The support piece  15  is provided on a rear portion thereof with a slotted hole  33  extending along a longitudinal direction thereof. The support piece  15  is formed to have, on a lower side of the support piece  15 , a convex portion  35  protruding downward, which has an inclined face  37   a  facing frontward (whose normal vector has a frontward component), an inclined face  37   b  facing rearward (whose normal vector has a rearward component), and a ridge portion  37   c  where these inclined faces intersect with each other. Specifically, the convex portion  35  is formed into a substantially triangular shape in a vertical cross section parallel to the longitudinal direction of the support piece  15 , whose width in the longitudinal direction thereof becomes narrower as it goes downward. 
   The elastic member  41  is fixed to an upper face of an upper corner portion of the radiator support  9 . The elastic member  41  is arranged under the support piece  15 , and has a base portion  43  set on the upper face of the radiator support  9 , and an elastic portion  47  extended frontward from the base portion  43 . The elastic portion  47  is formed into a substantially triangular wave shape in a vertical cross section parallel to the body longitudinal direction. The elastic portion  47  is formed to have, in a rear base portion thereof, a V-shaped concave portion  45  open upward, which has an inclined face  45   a  facing rearward (whose normal vector has a rearward component), an inclined face  45   b  facing frontward (whose normal vector has a frontward component), and a valley line portion  45   c  where these inclined faces intersect with each other. This concave portion  45  is engaged with the convex portion  35  of the support piece  15 . Further, the elastic member  41  is formed to have, on a distal end side portion in front of the concave portion  45 , an inclined face  39  facing frontward, and a ridge portion  39   a  where the inclined face  39  and the inclined face  45   a  intersect with each other. The elastic member  41  is a spring plate formed to be elastically deformable in a vertical direction. Specifically, the elastic portion  47  swings in the vertical direction about a support point  49  between the base portion  43  and the elastic portion  47 . 
   A procedure for mounting the front end module  1  described above on to the body will be described. 
   First, as shown in  FIG. 2 , both left-and-right ends of the front end module  1  are attached to the hood ledge member  3  and the front fender  7 . Specifically, as shown in  FIG. 1 , the upper attachment piece  21  of the front end module  1  is fastened to the hood ledge member  3  with the bolts  29 , and the lower attachment block  23  is fastened to the lower front end of the front fender  7  with the bolts  31 . At this time, as shown in  FIG. 3 , a bolt  53  for attachment of the headlamp unit  5  is not completely tightened or screwed into a nut  51  which is welded to a rear side of the radiator support  9 , and a bottom face  53   a  of a head of the bolt  53  is arranged above an upper face of the support piece  15  with a predetermined space interval δ 2  therebetween. 
   The support piece  15  of the headlamp unit  5  is thus put on an upper face of the elastic member  41  which is fastened to the radiator support  9 , and the headlamp unit  5  is temporarily supported so as to be movable in the longitudinal direction of the support piece  15 , or in the vehicle longitudinal direction. At this time, the convex portion  35  of the support piece  15  is set in a position in front of the concave portion  45  on the upper face of the elastic member  41 , with the inclined face  37   b  facing rearward thereof being in contact with the frontward-facing inclined face  39  of the elastic member  41 , so that the headlamp unit  5  can move rearward relative to the front end module  1 , when a thrust equal to or more than a predetermined threshold is applied rearward to the headlamp unit  5 . 
   Subsequently, as shown in  FIG. 4 , when the headlamp unit  5  is pushed rearward, the support piece  15  thereof moves rearward relative to the elastic member  41 , and the convex portion  35  of the support piece  15  ascends along the inclined face  39  of the elastic member  41 , whereby the support piece  15  is pushed up by the elastic member  41  and moves upward, and the elastic member  41  is elastically deformed downward (in a direction shown by a solid arrow in  FIG. 4 ). Then, the support piece  15  is lifted up and an upper face  15   a  thereof reaches a height of the bottom face  53   a  of the bolt head. Specifically, as shown by an arrow of  FIG. 4 , the headlamp unit  5  moves upward while moving rearward. 
   Thereafter, the headlamp unit  5  is further pressed rearward. Then, as shown in  FIG. 5 , the convex portion  35  of the support piece  15  comes in engagement with the concave portion  45  formed on the base side of the elastic member  41  of the ridge portion  39   a , and the headlamp unit  5  is prevented from moving rearward any further. As shown in  FIG. 6 , even if the convex portion  35  is not completely received in or engaged with the concave portion  45  and the support piece  15  is in a floated condition above the attachment portion of the radiator support  9 , the support piece  15  can be pressed against the elastic member  41  and given a rearward thrust by tightening the bolt  53 . Then, the inclined face  37   a  or ridge portion  37   c  of the convex portion  35  slides down on the inclined face  45   a  of the concave portion  45  of the elastic member  41 . Accordingly, the headlamp unit  5  further moves rearward. Specifically, as shown by an arrow of  FIG. 5 , the headlamp unit  5  moves downward while moving rearward. 
   Functions and effects of the embodiment of the present invention will be described below. 
   The mounting device  13  described above includes the support piece  15  which is provided on the rear side of the headlamp unit  5  and has the convex portion  35  protruded thereon, and the elastic member  41  which is provided on the radiator support  9  and has the concave portion  45  to be engaged with the convex portion  35  of the support piece  15 . These convex portion  35  and concave portion  45  are formed to engage with each other, thus securing the headlamp unit  5  to the radiator support  9 . Moreover, the convex portion  35  includes the inclined faces  37   a  and  37   b , and the concave portion  45  includes the inclined faces  45   a ,  45   b  and  39 . Therefore, when the headlamp unit  5  is pressed rearward, the ridge portion  37   c  of the convex portion  35  of the support piece  15  ascends along the inclined face  39  of the elastic member  41 , and climbs over the ridge portion  39   a  thereof. After the headlamp unit  5  is moved rearward by a predetermined amount δ 3  relative to the radiator support  9 , the convex portion  35  of the support piece  15  slides down along the inclined face  45   a  of the concave portion  45  of the elastic member  41 . This sliding motion provides the headlamp unit  5  with the rearward thrust. In such a way, mounting work of the headlamp unit  5  is performed efficiently. 
   The convex portion  35  of the support piece  15  is formed into the substantially triangular shape in cross section. Moreover, the concave portion  45  of the elastic member  41  is formed into the substantial V shape in cross section. Accordingly, the headlamp unit  5  is given a rearward thrust smoothly, and the mounting work of the headlamp unit  5  is performed more efficiently. 
   The elastic member  41  is the spring plate formed to be elastically deformable in a vertical direction or in a direction substantially orthogonal to a direction of the rearward movement of the headlamp unit  5  toward the attachment position thereof, and the support piece  15  of the headlamp unit  5  is flexibly supported on the elastic member  41 . Accordingly, the gap between the headlamp unit  5  and the front fender  7  can be constantly set to a predetermined size. Moreover, even when the headlamp unit  5  is put in a position in the rear of the attachment position thereof, the rearward-facing inclined face  37   b  of the convex portion  35  of the support piece  15  slides down along the frontward-facing inclined face  45   b  of the concave portion  45  of the elastic member  41 , while the elastic member  41  recovers its original shape, and thus the position of the headlamp unit  5  is automatically adjusted. Accordingly, interference between the headlamp unit  5  and the front fender  7  can be prevented, thus eliminating scratches of the front fender  7 . Furthermore, the headlamp unit  5  can be given a rearward thrust by the spring force of the elastic member  41 , whereby the mounting work of the headlamp unit  5  can be performed efficiently. 
   Furthermore, by tightening the bolt  53  for fastening the support piece  15  of the headlamp unit  5  to the elastic member  41  of the radiator support  9 , the headlamp unit  5  is further moved rearward to its final attachment position, thus reducing the variations in the attachment position of the headlamp  5  depending on workers. Even in the case that the headlamp unit  5  is pushed too much to the rear side, the headlamp unit  5  can be returned to the final attachment position thereof, using the spring force of the elastic member  41  and the fastening force of the bolt  53 , whereby the gap between the headlamp unit  5  and the front fender  7  is adjusted to a predetermined size. 
   The preferred embodiment described herein is illustrative and not restrictive, and the invention may be practiced or embodied in other ways without departing from the spirit or essential character thereof. The scope of the invention being indicated by the claims, and all variations which come within the meaning of claims are intended to be embraced herein. 
   The present disclosure relates to subject matters contained in Japanese Patent Application No. 2004-030569, filed on Feb. 6, 2004, the disclosure of which is expressly incorporated herein by reference in its entirety.