[001] The present subject matter described herein, relates to an impact energy absorber for front end of vehicle, and, in particular, to an energy absorber for front bumper of the vehicle to absorb impact energy thus protecting leg of pedestrian and reducing injury to pedestrian upon impact. In more particularly, the present subject matter relates to a structure of a collapsible bracket and placement of the collapsible bracket above towing hook for reducing pedestrian leg injury during side collision of vehicle with the pedestrian.
BACKGROUND AND PRIOR ART:
[002] Current bumper systems are formed of plastic material to absorb impact energy during collision. Further, the bumper system has an energy absorber which absorbs energy during pedestrian impact with the vehicle. There are several zones, such as upper leg and lower leg where vehicle hit the pedestrian. Further, the pedestrian leg injury is much more severe during impact with front towing hook of the vehicle which is usually has very stiff structure. The upper leg energy absorber is provided at the upper side of the bumper where upper part of radiator is mounted. Further, the lower leg energy absorber is provided at lower side where lower part of the radiator is mounted.
[003] When vehicle hits the pedestrian directly from the front side at the towing hook location, the front bumper does not absorb the impact energy which causes high intensity injury to the leg of the pedestrian. Impact of the pedestrian with the towing hook may cause fracture in the bone of the lower leg at tibia location.
[004] To make the vehicle safe for pedestrians, safety regulations are to be followed. If any vehicle does not fulfill the safety regulations, it would be dangerous for pedestrians.
[005] Fig. 1a illustrates conventional design of the energy absorber to absorb the impact energy and protect the pedestrian from injuries. The energy absorber 104 is placed across width of frond end of the vehicle behind the bumper. The energy absorber 104 is used to limit the pedestrian leg injury by absorbing the impact energy. The energy absorber 104 is mounted on front bumper beam 102 of the vehicle. When the pedestrian legform 106 hits the vehicle from front side, the energy absorber 104 absorbs the impact energy and saves the pedestrian leg from injury. Figure 2 illustrates the structure of the energy absorber 104. As illustrated from the figure 2, the energy absorber 104 has complex structure. Figure 3 illustrates the mounting of energy absorber 104 across the width of the vehicle at the front side. The energy absorber 104 induces huge tooling as well as material cost. Further, the energy absorber 104 has complex design and high weight.
[006] Figure 4 illustrates the front view of the vehicle and section A-A illustrates the side section where towing hook is located in the vehicle. Figure 5 illustrates the impact test with leg model or impact. In the figure 5, front side 504 of the vehicle collides with leg model 502. The leg model 502 has upper leg and lower leg. Portion above the knee is considered as upper leg and the lower portion is considered as the lower leg. The lower leg has several points, such as tibia 1, tibia 2, tibia 3, and tibia 4 where lower part of the vehicle causes injuries during impact of the pedestrian with the vehicle. At the lower front side of the vehicle a towing hook 506 at one side of the vehicle is given, the towing hook 506 causes more injury to the tibia 3 location of the lower leg during collision.
[007] Figure 6 illustrates the bending of the lower leg at the tibia 3 location during collision. In the absence of absorbers as mentioned above lead to increase in the Pedestrian leg injury value beyond the permissible limit at towing hood location. Injury value at Tibia-3 section which is near the towing hook 506 exceeds the permitted limit and hence, it was required to bring down the Tibia injuries. The reason for high Tibia 3 injury value is mainly due to the leg model 502 interaction with the towing hook 506 directly. Towing hook 506, which possess high stiffness applies high resistive forces to Leg model at Tibia 3 location resulting in high Tibia bending causing high Tibia bending moment at Tibia 3 location as shown in Figure 6.
[008] In order to improve the energy absorbing efficiency of the front bumper, sometime foam based absorbers are position in between the bumper and the vehicle mounting rails. Adding of these absorbers results in the cost increase of the bumper assembly of the vehicle. Further, the leg energy absorbers are not efficient which can protect the lower leg from the impact. Furthermore, the existing energy absorbers are expensive and complex in designing and manufacturing. Therefore, there is a need in the art to provide an energy absorber that can be more simple and inexpensive, and which can be placed over the towing hook to absorbs the impact energy and reduce the injury to the pedestrian's lower leg.
OBJECTS OF THE INVENTION:
[009] The principal objective of the present invention is to provide an energy absorber which absorbs impact energy and reduces injuries to lower leg of pedestrian.
[0010] Another object of the present subject matter is to provide a collapsible bracket for reducing pedestrian leg injury during vehicle collision.
[0011] Another object of the present subject matter is to provide collapsible bracket above towing hook location to reduce impact of hard towing hook on the pedestrian leg during vehicle collision with the pedestrian.
[0012] Yet another object of the present invention is to provide an energy absorbing collapsible bracket which is simple and inexpensive, and efficiently absorbs the impact energy above the towing hook without causing major injury to lower leg of the pedestrian.
SUMMARY OF THE INVENTION:
[0013] The subject matter disclosed herein relates to a collapsible bracket for reducing pedestrian leg injuries and damages during impact of the pedestrian leg with front side of the vehicle, in particularly to towing hook of the vehicle. The collapsible bracket is positioned in between the front radiator support member and front bumper of the vehicle. The collapsible bracket is placed above towing hook to reduce the impact of the towing hook on the pedestrian leg. The collapsible bracket is mounted over the radiator support member. The collapsible bracket is in U shape and, front overhanging portion of the U shaped collapsible bracket extend towards the front bumper. The overhang portion of the collapsible bracket extends in forward direction towards the front bumper a head of the towing hook. The overhang extended portion deforms during the collision to minimize the magnitude of the impact on the pedestrian leg from the towing hook. The collapsible bracket absorbs the impact energy and reduces the injuries cause to the lower leg.
[0014] In another embodiment of the present subject matter, structure of the collapsible bracket is illustrated. The collapsible bracket is in U shape and made of a single sheet material. Where one bent portion overhangs the towing hook and other end is mounted on radiator member support. The collapsible bracket has three zones, i.e., first zone, second zone, and third zone. The first zone which overhangs over the towing hook is bent in downward direction. The first zone is in proximity of back surface of the front bumper of the vehicle. There is small distance between the first zone of the collapsible bracket and the back surface of the front bumper which helps to engage the absorber at initial stage of impact and absorb higher impact energy. The first zone receives the impact from the pedestrian at first. The second zone starts immediately after the first zone. The second zone has a curvature in between the first zone and the second zone to initiate bending of the collapsible bracket upon impact from the pedestrian on the first zone. The third zone is the last zone which starts immediately after the second zone. The third zone has two extended flanges which attached with the front end, specifically radiator support member of the vehicle. The third zone is mounted on the front end of the vehicle, where the first zone and the second zone overhang ahead of the towing hook. The collapsible bracket has plurality of beads in longitudinal direction to provide adequate stiffness in direction of the impact. The first zone receives the impact of the leg form from the back surface of the front bumper and transfers the impact to the second zone through bent curvature. The bent curvature allows bending of the first zone and the second zone in downward direction to absorb impact energy. The collapsible bracket deforms to absorb the impact energy and reduces the impact of injuries on the pedestrian leg.
[0015] In order to further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit scope of the present subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0017] Fig. 1 illustrates placement of energy absorber across width of the vehicle as known in the art;
[0018] Fig. 2 illustrates structure of the energy absorber as known in the art;
[0019] Fig. 3 illustrates placement of the energy absorber over the crash boxes of front end of the vehicle as known in the art;
[0020] Fig. 4 illustrate front end of the vehicle;
[0021] Fig. 5 illustrates cross section of the front end of the vehicle with leg model to explain impact of collision on tibia 3 location, in accordance in accordance with an embodiment of the present subject matter;
[0022] Fig. 6 illustrates bending of the leg model near the tibia 3 location during collision of the vehicle with the pedestrian, in accordance with an embodiment of the present subject matter;
[0023] Fig. 7 illustrates front part of the vehicle, in accordance with an embodiment of the present subject matter;
[0024] Fig. 8 illustrates structure of the collapsible bracket, in accordance with an embodiment of the present subject matter;
[0025] Fig. 9 illustrates plurality of beads on the surface of the collapsible bracket, in accordance with an embodiment of the present subject matter;
[0026] Fig. 10 illustrates location of the towing hook where collapsible bracket can be placed over the towing hook in the vehicle, in accordance with an embodiment of the present subject matter;
[0027] Fig. 11 illustrates location and mounting of the collapsible bracket over the towing hook in the vehicle, in accordance with an embodiment of the present subject matter;
[0028] Fig. 12 illustrates side view of the collapsible bracket over the towing hook, in accordance with an embodiment of the present subject matter;
[0029] Fig. 13 illustrates cross section B-B of the collapsible bracket mounted on the front side of the vehicle above the towing hook, in accordance with an embodiment of the present subject matter;
[0030] Fig. 14 illustrates cross section B-B before collision, in accordance with an embodiment of the present subject matter;
[0031] Fig. 15 illustrates cross section B-B before collision of the mounted collapsible bracket over the towing hook, in accordance with an embodiment of the present subject matter;
[0032] Fig. 16 illustrates cross section B-B during collision of the mounted collapsible bracket over the towing hook and illustrate deformation of the collapsible bracket, in accordance with an embodiment of the present subject matter;
[0033] Fig. 17 illustrates test result of the tibia bending moment before and after implementation of the collapsible bracket over the towing hook, in accordance with an embodiment of the present subject matter; and
[0034] Fig. 18 illustrates the energy absorbed by the collapsible bracket during vehicle collision, in accordance with an embodiment of the present subject matter.
[0035] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0036] The subject matter disclosed herein relates to a collapsible bracket for reducing pedestrian leg injuries and damages during impact of the pedestrian leg with front side of the vehicle, in particularly to towing hook of the vehicle. The collapsible bracket is positioned in between the front radiator support member and front bumper of the vehicle. The collapsible bracket is placed above towing hook to reduce the impact of the towing hook on the pedestrian leg. The collapsible bracket is mounted over the radiator support member. The collapsible bracket is in U shape and, front overhanging portion of the U shaped collapsible bracket extend towards the front bumper. The overhang portion of the collapsible bracket extends in forward direction towards the front bumper. The overhang extended portion deforms during the collision to minimize the magnitude of the impact on the pedestrian leg from the towing hook. The collapsible bracket absorbs the impact energy and reduces the injuries cause to the lower leg.
[0037] In another embodiment of the present subject matter, structure of the collapsible bracket is illustrated. The collapsible bracket is in U shape and made of a single sheet material. Where one bent portion overhangs the towing hook and other end is mounted on radiator member support. The collapsible bracket has three zones, i.e., first zone, second zone, and third zone. The first zone which overhangs over the towing hook is bent in downward direction. The first zone is in proximity of back surface of the front bumper of the vehicle. There is small distance between the first zone of the collapsible bracket and the back surface of the front bumper which helps to engage the absorber at initial stage of impact and absorb the impact energy. Initially, the first zone receives the impact from the pedestrian legform. The second zone starts immediately after the first zone. The second zone has a curvature in between the first zone and the second zone to initiate bending of the collapsible bracket upon impact from the pedestrian on the first zone. The third zone is the last zone which starts immediately after the second zone. The third zone has two extended flanges which attached with the front end, specifically radiator support member of the vehicle. The third zone is mounted on the front end of the vehicle, where the first zone and the second zone over hang the towing hook. The collapsible bracket has plurality of beads in longitudinal direction to provide adequate stiffness in direction of the impact. The first zone receives the impact of the legform from the back surface of the front bumper and transfers the impact to the second zone through bent curvature. The bent curvature allows bending of the first zone and the second zone in downward direction to absorb impact energy. The collapsible bracket deforms to absorb the impact energy and reduces the impact of injuries on the pedestrian leg.
[0038] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures.
[0039] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0040] Fig. 7 illustrates front portion of the vehicle. In the front portion, the collapsible bracket can be placed over the towing hook to reduce the impact of towing hook on the pedestrian leg. The collapsible bracket overhangs over the towing hook and deforms during collision and absorbs the impact energy. Fig. 8 illustrates the structure of the collapsible bracket, in accordance with the present subject matter. The collapsible bracket 800 is in U shape and made of a single sheet material. The collapsible bracket 800 is divided into three zones, i.e., first zone 802, second zone 804, and third zone 806. The first zone 802 is bent in downward direction and overhangs over the towing hook. It should be noted that first zone 802 may be bent in upward direction to achieve the same objective. Front surface of the first zone 802 is in proximity of back surface of the front bumper of the vehicle. There is small distance between the first zone 802 of the collapsible bracket 800 and the back surface of the front bumper. The small distance between the first zone 802 and the front bumper helps to engage the absorber at early stage of impact and absorb higher impact energy. At first, the first zone 802 receives the impact from the pedestrian through the front bumper.
[0041] The second zone 804 starts immediately after the first zone 802. As illustrated in the figure 8 and 9, the second zone 804 has a curvature 810 in between the first zone 802 and the second zone 804 to initiate bending of the collapsible bracket 800 upon impact from the pedestrian on the first zone 802. The second zone 804 is the area which absorbs the impact energy of the collision and deforms to protect the leg of the pedestrian. The third zone 806 is the last zone which starts immediately after the second zone 804. The third zone 806 has two extended flanges 806a and 806b that can be attached with the front end, specifically radiator support member of the vehicle. The third zone 806 is mounted on the front end of the vehicle, where the first zone 802 and the second zone 804 over hang over the towing hook in forward direction of the vehicle.
[0042] The collapsible bracket 800 has plurality of beads 808 in longitudinal direction to provide adequate stiffness in direction of the impact. Further, the number of beads 808 can be optimized as per the stiffness requirement of absorber. Further, the size of the collapsible bracket can be optimized as per the requirements of the vehicle. For example, the vehicles which are big in size and shape accordingly the size of the towing hook increases, based on the size of the towing hook and front bumper profile of the vehicle, number of beads and size of the collapsible bracket can be optimized. The first zone 802 receives the impact of the Legform from the back surface of the front bumper and transfers the impact energy to the second zone 804 through bent curvature 810. The bent curvature 810 allows bending of the first zone 802 and the second zone 804 in downward direction to absorb impact energy of the collision. The collapsible bracket 800 deforms to absorb the impact energy and reduces the impact of injuries on the pedestrian leg.
[0043] Figure 10 illustrates the location of the towing hook in the lower front part of the vehicle where collapsible bracket can be mounted or placed. Figure 11 illustrate the mounting of collapsible bracket on the front cross member of the vehicle. In the figure 11, the collapsible bracket 1102 is mounted over the towing hook 1106. The collapsible bracket 1102 is mounted on front cross member 1104 of the vehicle. The collapsible bracket 1102 can be mounted anywhere on the front end of the vehicle which is hard enough to stop the motion of the collapsible bracket 1102 in backward direction during collision. More particularly, the collapsible bracket 1102 is mounted on the radiator support member 1104 of the vehicle where radiator is mounted. Generally, radiator is mounted on the upper cross member and the lower cross member of the vehicle. The collapsible bracket 1102 is mounted on the radiator cross member 1104 through the spot welding. It should be note that collapsible bracket 1102 can be mounted by any other joining means, such as gas welding, screw and bolt. Further, the alternate joining means depend on the vehicle requirement and strength of the front cross member. figure 12 illustrates the side view of the mounted collapsible bracket 1102 on the front cross member 1104 of the vehicle (mounting of collapsible bracket not visible in Fig-12 better will be to refer Fig-11). The collapsible bracket 1102 is placed over the towing hook 1106. Front portion, i.e., first zone and the second zone over hangs the towing hook 1106 to absorbs the impact energy during the collision and avoid impact of the pedestrian leg with the towing hook 1106.
[0044] Figure 13 illustrates cross section B-B of top view of the front bumper where towing hook is mounted. Figure 14 illustrates the cross section B-B view of the mounted collapsible bracket and towing hook. In the cross section, 1402 illustrates placement of front bumper, collapsible bracket, and towing hook. Figure 15 illustrates the enlarged view of cross section 1402. As illustrated in the enlarged view of cross section.
[0045] 1402, the collapsible bracket 1502 is mounted on the front cross member 508 of the vehicle over towing hook 1506. The extended portion of the collapsible bracket 1502 is in proximity of back surface of the front bumper fascia 1504. There is a small gap 1510 between the extended portion of the collapsible bracket 1502 and the back surface of the front bumper fascia 1504. The distance 1510 helps to engage collapsible energy absorber in initial stage of impact thereby increasing the energy absorption capability during collision of the vehicle with the pedestrian.
[0046] Fig. 16 illustrates the cross section B-B after the collision of the vehicle with the pedestrian, in accordance with the present subject matter. During the collision, impact force from the pedestrian legform pushes the front bumper towards inward direction. After absorbing some energy, the back surface of the front bumper transfers the impact energy on the collapsible bracket. The collapsible bracket deforms while absorbing the impact energy and reduces the impact of towing hook on the pedestrian leg. From the present collapsible bracket and placement of the collapsible bracket over the towing hook, injury to pedestrian leg during collision with vehicle can be reduced.
[0047] Fig. 17 illustrates a graph showing increase in the initial resistance to impact which help to reduce the peak tibia bending moment, in accordance with an embodiment of the present subject matter. In the figure 17, the red line/bold line indicates the tibia bending moment when no bracket was present. Where the green line/light line indicates the graphs of tibia bending moment when collapsible bracket was present on the towing hook. As illustrated by 1702, the initial resistance increased due to addition of collapsible bracket and 1704 illustrates peak tibia bending moment reduced with addition of collapsible bracket. Peak Tibia bending moment is the primary reason for fracture of tibia bone. The present collapsible bracket has helped to reduce peak tibia bending moment by 11.2 % and now the Tibia injury values are within acceptable levels.
[0048] Fig. 18 illustrates the energy absorbed by collapsible bracket in the graph. The collapsible bracket absorbs impact energy by undergoing plastic deformation when hit by pedestrian leg. This eventually helped to reduce the Tibia injury values.
[0049] It is easy to manufacture and assemble the present collapsible bracket in the vehicle. The present collapsible bracket can be easily manufactured using simple forming operation and can be assembled to vehicle using spot-welding, bolting or any other attachment method based on vehicle requirement. The present collapsible bracket is light weighted compared to the typical lower absorbers used across the industry. Further, the material, thickness, and bead pattern can be optimized based on specific vehicle requirement. The present energy absorber is simple and inexpensive.
[0050] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.

Claims:We claim:
1.A collapsible bracket (800, 1102, 1502) for reducing pedestrian leg injuries by absorbing impact energy during collision of vehicle with the pedestrian leg,
wherein the collapsible bracket (800, 1102, 1502) is in U shape and mounted on front end of the vehicle above towing hook (1106, 1506) to absorb the impact energy during collision.
2. The collapsible bracket (800, 1102, 1502) as claimed in claim 1, wherein the collapsible bracket (800, 1102, 1502) comprising:
a first zone (802) which bends in downward direction;
a second zone (804) which starts after the first zone (802); and
a third zone (806) which is the last zone that starts after the second zone, wherein the first zone (802), the second zone (804) and the third zone (806) are zones of single sheet.

3. The collapsible bracket (800, 1102, 1502) as claimed in claim 2, wherein the first zone (802) extends in forward direction and receives impact from front bumper.

4. The collapsible bracket (800, 1102, 1502) as claimed in claim 2, wherein the second zone (804) has a curvature (810) in between the first zone (802) and the second zone (804) to initiate bending of the U shaped collapsible bracket (800, 1102, 1502) upon impact.

5. The collapsible bracket (800, 1102, 1502) as claimed in claim 2, wherein the third zone (806) is attached with front cross member (1104) of the vehicle.

6. The collapsible bracket (800, 1102, 1502) as claimed in claim 1, wherein the collapsible bracket (800, 1102, 1502) is made from the single sheet material.
7. The collapsible bracket (800, 1102, 1502) as claimed in claim 1, wherein the collapsible bracket (800, 1102, 1502) has a plurality of bead (808) in longitudinal direction to provide adequate stiffness in direction of impact.

8. The collapsible bracket (800, 1102, 1502) as claimed in claim 1, wherein the collapsible bracket (800, 1102, 1502) is mounted in between front bumper and front cross member (1104) of the vehicle, wherein a distance is provided in between the collapsible bracket (800, 1102, 1502) and back surface of the front bumper fascia (1504).

9. The collapsible bracket (800, 1102, 1502) as claimed in claim 2, wherein the first zone (802) and the second zone (804) deforms upon impact from the pedestrian and reduce the pedestrian leg injury.

10. The collapsible bracket (800, 1102, 1502) as claimed in claim 2, wherein the first zone (802) and the second zone (804) extends in forward direction and overhangs in front of the towing hook (1106, 1506) in impact direction, the extended and over hanged portion of the collapsible bracket (800, 1102, 1502) deforms during collision to minimize magnitude of impact of the pedestrian leg with the towing hook (1106, 1506).