Abstract:
A bumper-stay structure for a vehicle, provided between a bumper back beam and a side member, for absorbing collision impact, may include a buffer member fixed to a front end of the side member and having a first impact absorbing member slidably absorbing the collision impact while the collision impact is applied to the bumper back beam, a support member, a front end of which is coupled to the bumper back beam and a rear end of which is telescopically mounted to a front end of the buffer member, wherein the rear end of the support member is pressingly coupled by the first impact absorbing member to the buffer member so that the first impact absorbing member maintains pressing contact with the support member while the collision impact is applied to the bumper back beam.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Korean Patent Application Number 10-2008-0093316 filed Sep. 23, 2008, the entire contents of which application is incorporated herein for all purposes by this reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a bumper-stay structure for a vehicle, and more particularly, to a bumper-stay structure for a vehicle, which can effectively absorb impact so as to cope with both low-speed and high-speed vehicle collisions. 
     2. Description of Related Art 
     In general, a vehicle is provided with a bumper installed on a front or rear part of a vehicle to protect a body, and the bumper serves to absorb impact when a vehicle collision occurs. 
       FIG. 1  is a perspective view illustrating an example of a conventional bumper stay for a vehicle, and  FIG. 2  is a perspective view illustrating another example of a conventional bumper stay for a vehicle. 
     In an example of a conventional bumper stay as illustrated in  FIG. 1 , side members constituting a body frame are provided on both sides of the body, and a bumper back beam  10  is provided on a front portion of the side member. Between the bumper back beam  10  and the side member, a bumper stay  20  for absorbing impact being transferred from the bumper back beam  10  is installed. 
     On the rear side of the bumper stay  20 , a plate  30  for coupling the bumper stay  20  to a front end of the side member is provided, and on the periphery of the bumper stay  20 , a deforming portion  20   a  for absorbing the impact is formed. 
     That is, when a high-speed vehicle collision occurs, the foaming portion  20   a  of the bumper stay  20  is deformed to absorb the impact which is transferred through the bumper back beam  10 , and thus passengers can be safely protected. 
     On the other hand, in another example of a conventional bumper stay as illustrated in  FIG. 2 , side members constituting a body frame are provided on both sides of the body, and a bumper back beam  10 ′ is provided on a front portion of the side member. Between the bumper back beam  10 ′ and the side member, a bumper stay  20 ′ for absorbing impact being transferred from the bumper back beam  10 ′ is installed. 
     On the rear side of the bumper stay  20 ′, a plate  30 ′ for coupling the bumper stay  20 ′ to a front end of the side member is provided. 
     The bumper stay  20 ′ includes a support plate  21  coupled to the bumper back beam  10 ′ by welding, a buffer member  22  coupled to the support plate  21 , and a coupling member  23  inserted by pressure into a front end of the buffer member  22  and coupled to the plate  30 ′. 
     That is, when a high-speed vehicle collision occurs, the buffer member  22  is deformed to absorb the impact which is transferred from the bumper back beam  10 ′, and thus passengers can be safely protected. 
     However, the examples of the conventional bumper stays  20  and  20 ′ as described above have the problems that, although the bumper stays  20  and  20 ′ can effectively absorb the impact when a high-speed vehicle collision occurs, they may not be deformed or may be bent when a low-speed collision occurs, and thus cannot effectively absorb the impact being transferred from the bumper back beam  10 . In this case, the impact is transferred to the body through the side members, and thus the safety of passengers is threatened. 
     The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art. 
     BRIEF SUMMARY OF THE INVENTION 
     Various aspects of the present invention are directed to provide a bumper-stay structure for a vehicle, which can effectively absorb an impact from a collision so as to cope with both low-speed and high-speed vehicle collisions, and thus can safely protect passengers with damage to the vehicle body being prevented. 
     In an aspect of the present invention, a bumper-stay structure for a vehicle, provided between a bumper back beam and a side member, for absorbing collision impact, may include a buffer member fixed to a front end of the side member through a plate and having a pressingly fixing portion formed on an inner periphery of the front end, and a support member having a front end coupled to the bumper back beam and a rear end inserted into the front end of the buffer member, and pressingly fixed by the pressingly fixing portion. 
     The pressingly fixing portion may project with a height greater than that of a deforming portion formed on the buffer member. 
     At least two pressingly fixing portions may be formed along a periphery of the buffer member. 
     A plurality of deforming portions may be formed on a periphery of the buffer member. 
     Guide grooves may be formed on a periphery of a through hole formed on a surface of the plate, and guide protrusions are formed on a periphery of the rear end of the support member to be slide ably inserted into the guide grooves. 
     In another aspect of the present invention, a bumper-stay structure for a vehicle, provided between a bumper back beam and a side member, for absorbing collision impact, may include a buffer member fixed to a front end of the side member and having a first impact absorbing member slidably absorbing the collision impact while the collision impact is applied to the bumper back beam, a support member, a front end of which is coupled to the bumper back beam and a rear end of which is telescopically mounted to a front end of the buffer member, wherein the rear end of the support member is pressingly coupled by the first impact absorbing member to the buffer member so that the first impact absorbing member maintains pressing contact with the support member while the collision impact is applied to the bumper back beam. 
     A guide protrusion may be formed on a periphery of the rear end of the support member, the buffer member is fixed to the front end of the side member through a plate formed on the front end of the side member, and the plate includes a through hole, so that the rear end of the support member is slidably insertable into the side member through the through hole when the collision impact is applied to the bumper back beam. 
     The guide protrusion may be cone-shaped. 
     A guide protrusion may be formed on a periphery of the rear end of the support member, the buffer member is fixed to the front end of the side member through a plate formed on the front end of the side member, the plate includes a through hole, and a guide groove is formed on inner periphery of the through hole so that the guide protrusion of the support member is slidably insertable into the guide groove of the side member when the collision impact is applied to the bumper back beam. 
     The first impact absorbing member may include a pressingly fixing portion protruding inwards from an inner periphery of the buffer member so as to pressingly contact outer periphery of the support member. 
     The support member may include a receiving groove at the rear end thereof to receive the pressingly fixing portion of the buffer member therein. 
     A second impact absorbing member may be formed along a periphery of the buffer member. 
     The second impact absorbing member may include deforming portion. 
     The first impact absorbing member may include a pressingly fixing portion protruding from an inner periphery of the buffer member so as to pressingly contact outer periphery of the support member. 
     The support member may include a receiving groove at the rear end thereof to receive the pressingly fixing portion of the buffer member. 
     The pressingly fixing portion may project inwards with a height greater than that of the deforming portion. 
     The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description of the Invention, which together serve to explain certain principles of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating an example of a conventional bumper stay for a vehicle. 
         FIG. 2  is a perspective view illustrating another example of a conventional bumper stay for a vehicle. 
         FIG. 3  is a side view illustrating an exemplary bumper-stay structure for a vehicle according to the present invention. 
         FIG. 4  is a sectional view illustrating an exemplary bumper-stay structure for a vehicle according to the present invention. 
         FIG. 5  is a sectional view taken along line A-A in  FIG. 4 . 
         FIGS. 6A and 6B  are views explaining the operation of an exemplary bumper-stay structure for a vehicle according to the present invention when a low-speed vehicle collision occurs. 
         FIGS. 7A to 7C  are views explaining the operation of an exemplary bumper-stay structure for a vehicle according to the present invention when a high-speed vehicle collision occurs. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims. 
     Hereinafter, a bumper-stay structure for a vehicle according to various embodiments of the present invention will be described in detail with reference to  FIGS. 3 to 7B . 
     A bumper-stay structure  1000  for a vehicle according to various embodiments of the present invention, as illustrated in  FIGS. 3 and 4 , is provided between a bumper back beam  1  and a side member  2 , and absorbs impact being transferred from the bumper back beam  1  to prevent the impact from being transferred to the side member  2  when a low-speed or high-speed vehicle collision occurs. 
     The bumper-stay structure  1000  for a vehicle according to various embodiments of the present invention includes a buffer member  200  fixed to a front end of the side member  2  through a plate  100 , and a support member  300  coupled to the bumper back beam  1  and a front end of the buffer member  200 . 
     The plate  100  is provided to couple the buffer member  200  to the side member  2 , and is attached to the front end of the side member  2  by welding. In the center of a front surface of the plate  100 , a through hole  110  is formed to connect with the side member  2 , and on an inner periphery of the through hole  110 , one or more guide grooves  120  are formed to stably guide the support member  300  to the inside of the side member  2  so that the support member  300  is inserted into the side member  2 . For example, three guide grooves  120  are formed at specified intervals on a periphery of the through hole  110 . 
     That is, the plate  100  fixes the buffer member  200  to the side member  2 , and guides the support member  300  so that the support member  300  is inserted into the side member  2  when a vehicle collision occurs. 
     The buffer member  200  is in the form of a cylinder so that it can effectively absorb the impact when a high-speed collision occurs. A rear end of the buffer member  200  is coupled to an outer periphery of the through hole  110  by bolts or welding, and a plurality of deforming portions  210  is formed along the circumference of the buffer member  200  to make the buffer member deformed during the vehicle collision. On the front end of the buffer member, a pressingly fixing portion  220  for pressingly fixing the support member  300  is formed. 
     The deforming portion  210  is a foaming groove depressed along the outer periphery of the buffer member  200 , and when the vehicle collision occurs, the deforming portions  210  are deformed inwardly and outwardly to absorb the impact. 
     In various embodiments of the present invention, the deforming portions  210  may be formed in the longitudinal direction of the buffer member  200  along the circumference thereof to increase efficiency to absorb the impact. 
     It is preferable that the pressingly fixing portion  220  that is formed to project inwardly of the buffer member  200  with a height greater than that of the deforming portion  210 . Accordingly, the support member  300  is prevented from being interfered with the deforming portion  210  while the support member  300  is moved. However the position of the pressingly fixing portion  220  is not limited to the front end of the buffer member  200 . It can be positioned in the middle or other place along the buffer member  200  so as to absorb the collision impact. 
     That is, as illustrated in an enlarged view of  FIG. 4 , the pressingly fixing portion  220  is formed to project as high as “a” from outer surface of the buffer member  200 , while the deforming portion  210  is formed to project as high as “b” from the outer surface of the buffer member  200 , and by a difference between “a” and “b”, the support member  300  is prevented from being interfered with the deforming portion  210  when the support member  300  is moved. 
     In various embodiments of the present invention, at least two, and preferably, four or more pressingly fixing portions  220  may be formed on the inner periphery of the front end of the buffer member  200  to achieve a stable fixing of the support member  300  and to prevent the rotation of the support member  300 . 
     In other embodiments of the present invention, the support member  300  may include a receiving groove  320  having substantially the same curvature as that of the pressingly fixing portion  220  of the buffer member  200  so that the support member  300  can be stably coupled to the buffer member  200 . 
     The support member  300  is provided to effectively absorb the impact when a low-speed vehicle collision occurs. The front end of the support member  300  is coupled to the end part of the bottom surface of the bumper back beam  1  by bolts or welding, and the other end of the support member  300  is inserted into and pressingly fixed to the front end of the buffer member  200  by the pressingly fixing portions  220 . 
     That is, the support member  300  is inserted into the buffer member  200  by the bumper back beam  1  when the low-speed vehicle collision occurs. At this time, since the support member  300  is inserted into the buffer member  200  in a state that it is pressingly fixed by the pressingly fixing portions  220 , it absorbs the impact being transferred to the bumper back beam  1 . 
     At the other end of the support member  300 , as illustrated in  FIG. 5 , guide protrusions  310  are formed to be slidably inserted into the guide grooves  120 . 
     That is, when a high-speed vehicle collision occurs, the guide protrusions  310  of the support member  300  are inserted into the guide grooves  120 , and thus the deforming portions  210  of the buffer member  200  are guided to be smoothly deformed by the bumper back beam  1 . 
     In various embodiments of the present invention, the guide protrusion  310  of the support member  300  may be a cone shape and the guide grooves  120  may not be formed at the plate  100  so that the guide protrusion  310  of the support member  300  may be slidably inserted into the through hole  110 . 
     Accordingly, when the low-speed vehicle collision occurs, the support member  300  slides into the buffer member  200  in a state that it is pressingly fixed to the front end of the buffer member  200 , and thus it absorbs the impact. 
     On the other hand, when a high-speed vehicle collision occurs, the support member  300  slides into the buffer member  200 , and then the whole deforming portions  210  of the buffer member  200  are deformed by the bumper back beam  1  to absorb the impact. 
     The operation of the bumper-stay structure for a vehicle having the above-described construction according to various embodiments of the present invention will be described with reference to  FIGS. 6A to 7C . 
     Low-Speed Vehicle Collisions 
     As illustrated in  FIGS. 6A and 6B , if a vehicle collision occurs during low-speed driving of the vehicle, impact is transferred to the bumper back beam  1  through a bumper, and the impact transferred to the bumper back beam  1  is effectively absorbed by the bumper-stay structure  1000  and cause most of the impact to vanish (See  FIG. 6A ). 
     That is, if a collision impact is transferred to the bumper back beam  1 , the support member  300  slides into the buffer member  200  in a state that the support member  300  is pressingly fixed by the pressingly fixing portions  220  of the buffer member  200  to absorb the impact, and thus the impact of the bumper back beam  1  is prevented from being transferred to the side member  2  (See  FIG. 6B ). 
     As described above, the impact being transferred to the bumper back beam  1  when a low-speed vehicle collision occurs is absorbed through the bumper-stay structure  1000 , and thus passengers can be safely protected. 
     High-Speed Vehicle Collisions 
     On the other hand, as illustrated in  FIGS. 7A to 7C , if a vehicle collision occurs during a high-speed driving of the vehicle, impact is transferred to the bumper back beam  1  through the bumper, and then transferred to the bumper-stay structure  1000  that supports the bumper back beam  1 . 
     That is, if a collision impact is transferred to the bumper back beam  1 , the support member  300  slides into the buffer member  200  in a state that the support member  300  is pressingly fixed by the pressingly fixing portions  220  of the buffer member  200  to firstly absorb the impact, and thus the impact of the bumper back beam  1  is firstly prevented from being transferred to the side member  2  (See  FIG. 7A ). 
     Then, the guide protrusions  310  formed at the front end of the support member  300  slide into the side member  2  as they are coupled to the guide grooves  120  formed on the plate  100  (See  FIG. 7B ). 
     Then, the deforming portions  210  of the buffer member  200  are buckled by the collision impact being transferred to the bumper back beam  1  to secondly absorb the impact being transferred from the bumper back beam  1 , and thus the impact of the bumper back beam  1  is secondly prevented from being transferred to the side member  2  (See  FIG. 7C ). 
     As described above, the impact being transferred from the bumper back beam  1  when a high-speed vehicle collision occurs is twice absorbed through the bumper-stay structure  1000 , and thus passengers can be safely protected. 
     For convenience in explanation and accurate definition in the appended claims, the terms, “front” and “rear”, are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures. 
     The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.