Patent Publication Number: US-2022219632-A1

Title: Bumper attachment device

Description:
FIELD OF THE INVENTION 
     The present invention relates to a bumper attachment device. 
     BACKGROUND OF THE INVENTION 
     A bumper attachment device for attaching a bumper face to a vehicle body is known (for example, Patent Document 1). The bumper attachment device includes a main body attached to a vehicle body, and elastic claws for engaging engagement holes formed in the bumper face. The elastic claw of the bumper attachment device includes an elastic beam, and a claw portion formed at the beam, and the claw portion enters the engaging hole by elastic deformation of the beam. 
     PRIOR ART DOCUMENT 
     Patent Document 
     
         
         Patent Document 1: Japanese Patent No. 4518406 
       
    
     SUMMARY OF THE INVENTION 
     The Subject to be Solved by the Invention 
     In order to prevent detachment of the bumper face to a bumper fixing portion, it is considered to increase rigidity of the beam. However, if the rigidity of the beam is increased, when the bumper face is attached to the bumper attachment device, the beam is hard to bend, so that there is a trouble of decreasing the operation ability in attachment. 
     The present invention has been made in view of the above background, and it is an object of the present invention to surely prevent detachment without losing operation ability. 
     Means for Solving the Problems 
     In order to solve the above problems, one aspect of the invention is a bumper attachment device ( 1 ) for attaching a bumper face ( 3 ) to a vehicle body ( 4 ), comprising a main portion ( 18 ), vehicle body connection portions ( 19 ) provided at the main portion and adapted to be connected to the vehicle body, elastic claws ( 20 ) provided at the main portion and adapted to engage engaging holes ( 15 ) formed at the bumper face, wherein the elastic claw extends from the main portion, and includes a beam ( 35 ) having elasticity and a claw portion ( 36 ) projecting from a tip portion of the beam to a side portion, the claw portion includes a check face ( 41 ) engaging a hole wall ( 65 ) of the engagement hole, and the check surface has a dent and projection shape ( 51 ). 
     In the aspect, by the dent and projection shape, a friction force acting between the check face and the hole wall of the engagement hole can be increased. Thereby, sliding of the check face relative to the hole wall of the engagement hole is suppressed, and it is possible to keep a state where the claw portion hangs on the hole wall of the engagement hole. In the aspect, since the rigidity of the cantilever is not increased, the operation ability at the time of assembly is not lost, and detachment of the bumper attachment device is surely prevented. 
     Also, in the above aspect, the dent and projection shape has a plurality of projections ( 54 ) extending parallel to each other, and each of the projections extends perpendicular to a projecting direction relative to the beam of the claw portion, and perpendicular to an extending direction of the beam. 
     In the aspect, since the projection engages the opening edge of the engagement hole, sliding of the check surface relative to the hole wall of the engagement hole is further suppressed. 
     Also, in the above aspect, the check surface extends to a base end side of the beam toward a tip end side of the claw portion. 
     In the aspect, when the claw portion enters the engagement hole at the time of assembly, it is possible to avoid contact between the dent and projection shape and the hole wall of the engagement hole. Accordingly, it is possible to enter the claw portion to the proper position relative to the engagement hole. 
     Also, in the above aspect, a surface of the dent and projection shape is preferably roughened. 
     In the above aspect, it is possible to increase frictional force formed between the dent and projection shape and the hole wall of the engagement hole. 
     In the above aspect, it is preferable to have an inclination surface ( 40 ) extending in a projection direction of the claw portion toward an end side, and a connection surface ( 44 ) smoothly connecting the inclination surface and the check surface. 
     In the aspect, the claw portion can smoothly enter the engagement hole. 
     In the above aspect, preferably, the main portion extends along the outer surface of the vehicle body, and the body connection portion is formed to project on the rear surface of the main portion and engages the engagement hole ( 9 ) of the vehicle body. 
     In the aspect, the body connection portion is engaged with the engagement hole of the vehicle body, so that the bumper attachment device can be attached to the front surface of the vehicle. 
     Also, in the above aspect, the bumper face includes a bumper face main portion ( 10 ) forming an outer surface of the vehicle body, and edge wall portions ( 13 ) projecting substantially perpendicularly from an end ( 11 ) of the bumper face main portion relative to the bumper face main portion, and the engagement holes are formed in the edge wall portion. 
     In this aspect, the bumper face is pushed perpendicular to the vehicle body, so that the bumper face is attached to the vehicle body through the bumper attachment device. 
     In the aspect, a front end portion ( 5 ) of the vehicle body includes a bumper connection portion ( 7 ) connecting to the bumper face, and a step portion ( 8 ) defining a dent portion of the vehicle body by connecting to the bumper connection portion, and the edge wall portion enters the dent portion and is located to face adjacent to the step portion. 
     In this aspect, by pushing the edge wall portion of the bumper face to the dent portion of the body portion, the outer surface of the bumper face is flush with the outer surface of the body portion. Thereby, design of the vehicle is enhanced. 
     In the above aspect, the beam portion is provide at a side surface portion ( 23 ) of the main portion, and extends from a rear surface portion ( 22 ) side to a front face portion ( 21 ) side of the main portion, and the side surface portion of the main portion includes grooves ( 58 ) receiving the edge wall portion. 
     In the aspect, the bumper face can be fixed to the edge wall portion by the beam of the bumper attachment device and the groove. 
     Advantages of the Invention 
     In the above structure, in the bumper attachment device, it is possible to surely prevent detachment without losing operation ability at the assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view showing an attachment structure of a bumper face to a front fender using a bumper attachment device of the present invention. 
         FIG. 2  is a perspective view showing the bumper attachment device. 
         FIG. 3  is a perspective view showing the bumper attachment device. 
         FIG. 4  is a perspective view showing the bumper attachment device. 
         FIG. 5  is a plan view showing the bumper attachment device. 
         FIG. 6  is a perspective view showing a check face of a claw portion. 
         FIG. 7  is a sectional view showing an attachment structure of the bumper face to a front fender using the bumper attachment device. 
         FIG. 8  is a sectional view showing an attachment structure of the bumper face to the front fender using the bumper attachment device. 
         FIG. 9  is a sectional view showing an attachment structure of the bumper face to the front finder using the bumper attachment device in a state that a removing force is applied to the bumper face. 
     
    
    
     EMBODIMENTS OF THE INVENTION 
     Hereinafter, with reference to the drawings, embodiments of the bumper attachment device  1  of the invention will be explained. In  FIG. 1 , the bumper attachment device  1  is used to attach a bumper face  3  to a vehicle body. The bumper face  3  may be either one of a front bumper face and a rear bumper face. In the following explanation, an example of the bumper attachment device  1  where the bumper face  3  as the front bumper face is attached to a front fender  4  as a vehicle. 
     The front fender  4  which is a part of the vehicle forms front portions of left and right side portions of the vehicle. The front fender  4  is formed of a steel plate. A front end  5  of the front fender  4  is provided with a bumper connection portion  7  connected to the bumper face  3 . The bumper connection portion  7  is dented through a step portion  8  at an inside in the vehicle width direction relative to other portions of the front fender  4 . Namely, the bumper connection portion  7  and the step portion  8  define a dent. The bumper connection portion  7  of the vehicle extends along a front edge of the front fender  4 . The bumper connection portion  7  is formed with a plurality of engagement holes  9  penetrating therethrough in a thickness direction. 
     The bumper face  3  is a member covering a front side of the front bumper extending in the left and right directions of the front end  5  of the vehicle. The bumper face  3  includes a bumper face main portion  10  in a plate shape, and an edge wall portion  13  provided at an end  11  of the bumper face main portion  10 . The bumper face  3  is formed of a resin material. The bumper face main portion  10  extends in the left and right directions, and both end portions bend in the rear direction. The left and right ends  11  of the bumper face main portion  10  face, from an outer side, the bumper connection portion  7  of the front fender  4  at the left and right corresponding thereto. The left and right of the end  11  of the bumper face main portion  10  extend along the step portion  8 , and are connected to the bumper connection portion  7 . The edge wall portion  13  projects about perpendicularly from an edge  14  of the bumper face main portion  10  to a rear side of the bumper face main portion  10 . Namely, the edge wall portion  13  enters the dent portion of the vehicle. The respective portions of the edge wall portion  13  provided at the left and right of the end face the step portion through a small gap. Namely, the wall portion  13  is adjacent to the step portion. The respective portions of the wall portion  13  provided at the left and right of the end  11  are formed with a plurality of engaging walls  15 . 
     The bumper attachment device  1  is connected to the bumper connection portion  7 , and by engaging the edge wall portion  13  of the bumper face  3 , the bumper face  3  is fixed to the front fender  4 . 
     As shown in  FIG. 1  and  FIGS. 2-5 , the bumper connection device  1  includes a main portion  18 , body connection portions  19  connecting with the front fender  4 , and elastic claws  20  engaging the bumper face  3 . The bumper attachment device is formed of resin. 
     The main portion  18  is formed with an elongated shape in a cubic form, The main portion  18  includes an outer surface portion  21  forming a main face, a rear surface portion  22  formed at a side opposite to the front surface portion  21 , and side face portions  23  extending generally perpendicularly to the rear face portion  22  and the front face portion  21  and also extending in the longitudinal direction of the main portion  18 . Thickness reduce portions  24  are formed at appropriate positions of the rear face portion  22  and the front face portion  21 . 
     The body connection portions  19  are plural portions formed at the rear face portion  22  of the main portion  18 . Some of the body connection portions  19  may be first connection portions  27 , for example, having a plurality of open pieces  25  projecting with a space on the rear surface portion  22 . Namely, the body connection portion  19  preferably has projections. The plurality of open pieces  25  opens respectively with respect to each other by inserting a pin or screw between the open pieces. Some of the body connection portions  19  may be second connection portions  30  each having a leg portion  28  projecting from the rear face portion  22  and a claw portion  29  projecting in a side direction with respect to the leg portion  28 . The claw portion  29  has elasticity and is provided to be able to proceed and recede sideward relative to the leg portion  28 . Also, some of other body connection portions  19  may be third connection portions  31  which are through holes. Connecting members for connecting the main body portion  18  to the front fender  4  are installed in the third connection portions  31 . The connecting members may be, for example, fastener or screws connecting to the third connecting portions  31  penetrating through the front fender  4 . 
     A plurality of elastic claws  20  is formed along an elongated direction of the main portion  18  on one of the side face portions  23 . Each of the elastic claws  20  is formed in each of a plurality of dents  33  formed in the side face portions  23  of the main portion  18 . The dent  33  is dented from a side surface portion  23  of the main portion  18  inward of the main portion  18 , and opens at the front surface portion  21 . An end on the rear face portion  22  of the dent  33  includes an end face  34  facing the front face portion  21 . The plurality of dents  33  is arranged to be spaced apart from each other along an extending direction of the main portion  18 . Each elastic claw  20  is arranged in each of the dents  33  corresponding thereto, and is arranged along the extending direction of the main portion  18  to be spaced apart from each other. Each elastic claw  20  includes a beam  35  (cantilever) extending from the end face  34  of the dent  33  to the front face portion  21 , and a claw portion  36  projecting from a front end of the cantilever to an outer side (side direction) relative to the main portion  18 . 
     The cantilever is a plate piece having a parallel outer surface relative to the side surface portion  23  of the main portion  18 . The outer surface of the cantilever is arranged on a plane substantially same as the side surface portion  23  of the main portion  18 . The cantilever has elasticity, and can deform in the projecting direction of the claw portion  36  and a direction opposite to the projecting direction. Each end face  34  of each dent  33  includes a through hole  39  penetrating through a thickness direction. The through hole  39  reduces rigidity of the end face  34 , and facilitates swinging movement of the cantilever. The through hole  39  preferably extends along an inner edge of a base portion of the cantilever. 
     As shown in  FIG. 6 , the claw portion  36  includes an inclined surface  40  at a tip side of the cantilever, and a check surface  41  at a base end side of the cantilever. The inclined surface  40  is a plane surface extending from the end side of the outer surface of the cantilever to the base end side in the direction of projection of the claw portion  36 , Namely, the check surface  41  is a face connecting the inclined surface  40  and an outer surface of the cantilever, and is provided on the base end side of the cantilever relative to the inclined surface  40 . The check surface  41  may be arranged substantially perpendicularly to the cantilever. The claw portion  36  includes, on both ends. a first side portion  42  and a second side portion  43  opposite to each other. The first side portion  42 , the second side portion  43  are connected respectively to the inclined surface  40 , the check surface  41  and the cantilever. The second side portion  43  includes a first surface portion  45  formed on the base end side of the claw portion  36 , and a second surface portion  46  formed on a tip side of the claw portion  36 . The first surface portion  45  and the second surface portion  46  incline to the first side portion  42  toward the tip side of the claw portion  36 . An inclination angle of the second surface portion  46  toward the first side portion  42  is set greater than an inclination angle of the first surface portion  45  to the first side portion  42 . By the inclination of the second side portion  43 , the inclination surface  40  and the check surface  41  become narrow in width to the end side of the claw portion  36 . A border (ridge portion) between the inclined surface  40  and the check surface  41  is smoothly connected by a connection surface  44 . The connection surface  44  is preferably a curved surface. 
     In the present embodiment, the check surface  41  extends toward the tip side of the claw portion  36  at the base side of the cantilever. Namely, the check surface  41  inclines at the base side of the cantilever. In other words, the check surface  41  overhangs relative to the outer surface of the cantilever, and forms an acute angle relative to the outer surface. 
     The check surface  41  includes a plurality of dent and projection shapes  51 . The dent and projection shapes  51  include at least one of a plurality of projections projecting relative to a standard surface of the check surface  41  and a plurality of dents denting relative to the standard surface. The plurality of dents and projections may be formed independently, or may be formed continuously. The plurality of dents and projections may be formed regularly to have a desired shape with respect to the check surface  41 , for example parallel to each other or in a grid shape. The size and shape of the respective projections and dents may be different from each other. The outer surfaces of the dents and projections may be roughened. For example, the outer surfaces of the dents and projections may be roughened by applying roughening processing, such as blast processing or texture treatment on an outer surface of the mold forming the bumper attachment device  1 . 
     In the present embodiment, preferably, the dent and projection shapes  51  are projections  54  which are a plurality of projections extending respectively parallel to each other and projecting on the check surface  41 . Preferably, the projections  54  respectively extend in a direction perpendicular to the projecting direction relative to the cantilever of the claw portion  36 , and perpendicular to the extending direction of the cantilever. Between the adjacent projections  54 , a groove  55  which is a dent extending parallel to the projections  54  is formed. In other embodiment, preferably, the dent and projection shapes  51  are a plurality of grooves  55  dented on the check surface  41 . 
     As shown in  FIG. 1  to  FIG. 5 , on the side surface portion  23  provided on a side where the elastic claw  20  of the main portion  18  is formed, grooves  58  for receiving the edge wall portion  13  of the bumper face  3  are formed. The groove  58  is defined by the side surface portion  23  of the main portion  18 , a plurality of bottom wall portions  59  projecting sideward from the side surface portion  23 , and a plurality of vertical wall portions  60  extending respectively from the tip end of the bottom wall portion  59  to a front surface portion  21  side of the main portion  18 . The groove  58  opens toward a front face side of the main portion  18 , and extends intermittently in the longitudinal direction. Preferably, the vertical wall portions  60  incline inwardly toward the tip end side. 
     On the side surface portion  23  of the main portion  18 , a plurality of projecting abutment portions  61  is formed. The projecting abutment portion  61  is, for example, a projection extending from a rear side of the main portion  18  to a front side. Preferably, the projecting abutment portion  61  is provided along an open edge toward the side surface portion  23  of each of the dents  33 . The projection end of the projecting abutment portion  61  is located on the main portion  18  side more than the inner surface side of the vertical wall portion  60 . 
     Next, an assembling structure and assembling method of the front fender  4  and the bumper face  3  using the bumper attachment device  1  are explained. First, to the plurality of engagement holes  9  provided in the bumper connection portion  7  of the front fender  4 , the corresponding body connection portions  19  of the bumper attachment device  1  are engaged, so that the bumper connection portion  7  of the front fender  4  is connected to the bumper attachment device  1 . When the first connection portion  27  is engaged with the engagement hole  9 , the plurality of open pieces  25  are opened by inserting pins or screws between the plurality of open pieces  25  from the front surface portion  21  side of the main portion  18  of the bumper attachment device  1 . Thereby, the first engagement portion  29  is prevented from disengagement to the engagement hole  9 . Also, the second engagement portion  30  is engaged with the engagement hole  9  by inserting the leg portion  28  to the engagement hole  9 . Namely, the projections of the body connection portions  19  are engaged with the engagement holes  9 . 
     In the state that the front fender  4  is engaged with the bumper attachment device  1 , in the bumper connection portion  7 , the bumper attachment device  1  extends along the step  8  of the front fender  4 . The bumper attachment device  1  is arranged such that the side surface portion  23  where the elastic claws  20  and the grooves  58  are provided faces the step portion  8  through the gap. The grooves  28  open in a direction opposite to a direction of the bumper connection portion  7 . 
     Next, as shown in  FIGS. 7-9 , the edge wall portion  13  provided at the end  11  of the bumper face main portion  10  is entered to the groove portions  58  of the bumper attachment device  1 , so that the bumper attachment device  1  is engaged with the bumper face  3 . At this time, the edge wall portion  13  abuts the respective claw portions  36  of the bumper attachment device  1 , and presses the claw portions  36  to the groove portion  33  side. Thereby, the cantilever elastically deforms and inclines inside the groove portions  33 . Thereafter, along with the movement into the groove portions  58  of the edge wall portion  13 , the tip portions of the claw portions  36  move on the surface of the edge wall portion  13  and arrive at the engagement holes  15 . The engagement hole  15  is defined by a hole wall  65 . When the claw portions  36  arrive at the engagement holes  15 , the cantilevers return and the claw portions  36  enter the engagement holes  15 . Thereby, the check surfaces  41  of the claw portions  36  face the hole walls  65  of the engagement holes  15 . Namely, the elastic claws  20  engage the engagement holes  15 . At this time, it is good that the extending direction of the cantilever is substantially parallel to the insertion direction of the edge wall portion  13 . In a state that the edge wall portion  13  is received in the groove portions  58 , the edge wall portion  13  is held by the vertical wall portions  60  and the abutting portions  61  shown in  FIG. 3 , and is set in position. 
     As shown in  FIG. 7  to  FIG. 9 , in a state that the bumper attachment device  1  is engaged with the bumper face  3 , the edge wall portion  13  at the left and right end portions  11  of the bumper face main portion  10  faces the step portion  8  of the front fender  4 . The edge portion  14  of the bumper face main portion  10  faces the boundary between the outer surface of the front fender  4  and the step portion  8 . The bumper face main portion  10  is arranged to be substantially flush with the outer surface of the front fender  4 . 
     Next, the operation of the bumper attachment device  1  when an extraction force is applied to the bumper face  3  is explained. Herein, the extraction force is a force applied in a direction to extract the bumper face  3  from the bumper attachment device  1 , and is applied outside of the front fender  4  along the edge wall portion  13  of the bumper face  3 . When the extraction force is applied to the bumper face  3 , the edge wall portion  13  moves to the extraction direction, and the hole wall  65  of the engagement hole  15  abuts the connection surface  44  provided at the tip end of the claw portion  36 . Thereafter, when the edge wall portion  13  further moves in the extraction direction, the hole wall  65  pushes the connection surface  44  of the tip portion of the claw portion  36 , and the claw portion  36  rotates and the cantilever elastically deforms to incline to the dent  33 . Thereby, an angle between the check surface  41  of the claw portion  36  and the hole wall  65  of the engagement hole  15  becomes small. At this time, the claw portion  36  moves, at the connection surface  44 , on the hole wall  65  of the engagement hole  15 . 
     Thereafter, when the edge wall portion  13  further moves to the extraction direction, the claw portion  36  further rotates, so that the dent and projection shape  51  of the check surface  41  of the claw portion  36  abuts the hole wall  65  of the engagement hole  15 . By the abutment of the dent and projection shape  51  against the hole wall  55  of the engagement hole  15 , a friction force between the check surface  41  of the claw portion  36  and the hole wall  65  of the engagement hole  15  increases, so that the movement of the claw portion  36  relative to the hole wall  65  is suppressed. At this time, the dent and projection shape  51  bites the corner portion  66 , so that the friction force between the hole wall  65  of the engagement hole  15  and the opening surface increases. Also, the dent and projection shape  51  engages the corner portion  66  between the hole wall  65  of the engagement hole  15  and the opening, so that the movement of the claw portion  36  relative to the hole wall  65  is further suppressed. Especially, when the dent and projection shape  51  has the projections  54 , since an area where the dent and projection shape  51  engages the corner portion  66  increases, the movement of the claw portion  36  relative to the hole wall  65  is further suppressed. 
     Since the movement of the claw portion  36  relative to the hole wall  65  is suppressed, the claw portion  36  is hardly disengaged from the engagement hole  15 , so that disengagement of the bumper face  3  from the bumper attachment device  1  for the removal force is hard. 
     Hereinafter, the advantages of the bumper attachment device are explained. When the extraction force is applied to the bumper face  3 , the dent and projection shape  51  of the check surface  41  at the claw portion  36  of the elastic claw  20  engages the hole wall  65  of the engagement hole  15 , so that the friction force operating between the check surface  41  and the hole wall  65  increases, so that the sliding movement of the claw portion  36  relative to the hole wall  65  is suppressed. Accordingly, the bumper face  3  is hardly removed, and the detachment of the bumper attachment device  1  is surely prevented. Also, the dent and projection shape  51  engages the corner portion  66  between the hole wall  65  of the engagement hole  15  and the opening, so that the sliding movement of the claw portion  36  relative to the hole wall  65  is further suppressed. Especially, in case the dent and projection shape  51  has the projections  54 , since the area at the portion where the dent and projection shape  51  engages the corner portion  66  increases, the sliding movement of the claw portion  36  relative to the hole wall  65  is further suppressed. Accordingly, the friction force acting between the check face  41  and the corner portion  66  is increased. Accordingly, the sliding of the check face  41  relative to the engagement hole  15  is suppressed, and it is possible to keep a state where the check face  41  hangs on the corner portion  66 . Thus, the bumper face  3  is hardly removed, and it is possible to surely prevent the detachment of the bumper attachment device  1 . In this structure, it is not necessary to increase the rigidity of the cantilever in order to increase the resisting force to the extraction force. Thus, it is not required to increase a force required to insert the elastic claw  20  to the engagement hole  15 , and the operation ability at the time of assembly is not lost. 
     Also, in the present embodiment, the dent and projection shape  51  is formed of a plurality of projections  54  which extends perpendicular to the projecting direction relative to the cantilever and perpendicular to the extending direction of the cantilever. Therefore, the extending direction of the projections  54  and the extending direction of the corner portion  66  of the engagement hole  15  are parallel to each other, so that it is possible to increase engaging area of the projections  54  and the corner portion  66 . Thereby, sliding between the check face  41  and the engagement hole  15  is further suppressed. 
     Also, in the present embodiment, the outer surface of the dent and projection shape  51  is roughened. Thereby, friction formed between the dent and projection shape  51  and the hole wall  65  of the engagement hole  15  is increased. Accordingly, sliding between the check surface  41  and the engagement hole  15  is further suppressed. 
     Further, the inclination surface  40  of the claw portion  36  of the elastic claw  20  of the bumper attachment device  1  and the check face  40  are connected smoothly by the connection surface  44 . Thereby, at the time of assembly of the bumper face  3 , the claw portion  36  can smoothly enter the engagement hole  15 . Therefore, the assembly can be made easily. Also, the check face  41  of the claw portion  36  extends to the base end side of the cantilever toward the tip side of the claw portion  36 . Accordingly, when the claw portion  36  enters the engagement hole  15  at the time of assembly, it is possible to prevent contact of the dent and projection shape  51  with the hole wall  65  of the engagement hole  15 . Thus, the claw portion  36  can enter to the suitable position in the engagement hole  15 . Accordingly, the assembly can be made easily. 
     As above, the explanation of the concrete embodiments is completed, but the present invention is not limited to the above embodiments, and can be modified widely. In the present embodiment, the beam  35  (cantilever) of the elastic claw  20  extends from the rear surface portion  22  side of the main portion  18  to the front surface portion  21  side, but in another embodiment, a cantilever may extend from the front face portion  21  side of the main portion  18  to the rear surface portion  22  side. In this case, the check surface  41  of the claw portion  36  may be provided on the tip side of the cantilever relative to the inclination surface  40 , i.e. on the rear surface  22  side of the main portion  18 . 
     Also, in the present embodiment, the beam  35  is a cantilever extending from the rear surface  22  side to the front surface portion  22  side of the main portion  18 , but in another embodiment, the beam  35  may be a double side beam. In this case, the double side beam is provided in the dent portion  33  to connect the rear surface portion  22  side and the front surface side  21  side of the main portion  18 . Also, the double side beam may be formed to elastically deform in a direction opposite to the projection direction of the claw portion  36 . 
     The dent and projection shape  51  may be formed at least partially on the check surface  41 , or formed entirely on the check surface  41 . The dent and projection shape may be set appropriately according to a shape of the hole wall  65  and the corner portion  66 . For example, the dent and projection shape  51  may include dents engageable with the corner portion  65 . Also, the tip portion of the projection in the dent and projection shape is preferably formed sharply. Accordingly, the projection of the dent and projection shape  51  easily bites the hole wall  65  of the engagement hole  15 , so that the sliding of the check surface  41  relative to the hole wall  65  is further suppressed. The projection of the dent and projection shape  51  may be formed, preferably, with a circular column shape or rectangular column shape with a sharp tip. Also, in order to prevent sliding of the hole wall  65  with the check face  41 , the dent and projection shape may be formed at the hole wall  65 , or the hole wall  65  may be roughened. 
     In the present embodiment, the bumper attachment device  1  is attached to the front fender  4  of the vehicle, in another embodiment, and the bumper attachment device  1  may attach the bumper face to a rear fender of the vehicle. Also, in a further embodiment of the invention, the bumper attachment device  1  may attach the bumper face  3  to a bracket provided on a vehicle. 
     EXPLANATION OF NUMERALS 
     
         
         
           
               1 : Bumper attachment device 
               3 : Bumper face 
               4 : Front fender (vehicle body) 
               5 : Front end portion 
               7 : Bumper connection portion 
               8 : Step portion 
               9 : Engagement hole 
               10 : Bumper face main portion 
               11 : End 
               13 : Edge wall portion 
               15 : Engagement hole 
               18 : Main portion 
               19 : Vehicle connection portion 
               20 : Elastic claw 
               21 : Front surface portion 
               22 : Rear surface portion 
               23 : Side surface portion 
               31 : Third connection portion 
               35 : Beam portion 
               36 : Claw portion 
               40 : Inclination surface 
               41 : Check surface 
               44 : Connection surface 
               51 : Dent and Projection shape 
               58 : Groove portion 
               65 : Hole wall