[0056]The orientation and position of slots can be varied as per the performance
requirement.
[0057]
En
ergy absorbing bracket help to significantly reduce the pedestrian head
injury (approx. 23%) in the event of collision of pedestrian head with vehicle
hood.
5
[0058]
The present deformable reinforcement reduces
Head Injury Criteria (HIC)
value
at the hood hinge reg
ion. The structure of the present deformable
reinforcement allow better energy absorbing capabilities during head impact at the
hood hinge region. The deformable reinforcement plastically deforms in a
specified manner according to the plurality of slots an
d
bending
portion to provide
10
better HIC values.
[0059]
It is easy to manufacture and assemble the present
deformable
energy
absorbing bracket
in the existing vehicles. There is no requirement to change the
current structure of the existing vehicles so there is n
o modification cost. Further,
there is no requirement to change the current layout. The present
deformable
15
energy absorbing bracket
can be implemented in the existing vehicle to make the
existing vehicles safe for pedestrian. The present
deformable
energy
absorbing
bracket
in the vehicle hood assembly meets the required HIC
value
for complying
pedestrian safety regulations. The present
deformable
energy absorbing bracket
is
light weighted
so addition of
deformable
energy absorbing bracket
does not add
20
too m
uch
extra weight to the vehicle. Further, the present
deformable
energy
absorbing bracket
does not need
any special welding facilities. Therefore, the
present
deformable
energy absorbing bracket
can be implemented in the existing
vehicle using existing fac
ilities.
[0060]
It will be further appreciated that functions or structures of a plurality of
25
components or steps may be combined into a single component or step, or the
functions or structures of one
-
step or component may be split among plural steps
or componen
ts. The present invention contemplates all of these combinations.
Unless stated otherwise, dimensions and geometries of the various structures
depicted herein are not intended to be restrictive of the invention, and other
30
18
dimensions or geometries are possi
ble. Plural structural components or steps can
be provided by a single integrated structure or step. Alternatively, a single
integrated structure or step might be divided into separate plural components or
steps. In addition, while a feature of the present
invention may have been
described in the context of only one of the illustrated embodiments, such feature
5
may be combined with one or more other features of other embodiments, for any
given application. It will also be appreciated from the above that the
fabrication of
the unique structures herein and the operation thereof also constitute methods in
accordance with the present invention. The present invention also encompasses
intermediate and end products resulting from the practice of the methods herein.
10
The use of “comprising” or “including” also contemplates embodiments that
“consist essentially of” or “consist of” the recited feature.
[0061]
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,
15
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 vehicle hood assembly (1300) for absorbing pedestrian head impact energy during collision of vehicle with pedestrian head, the vehicle hood assembly (1300) comprising:
a vehicle hood (1302);
a cowl panel (1303);
a hinge arm is mounted on the cowl panel (1303) from one end through hinge mounting bracket and other end is connected with the vehicle hood (1302), the vehicle hood moves up and down about horizontal pivot axis;
characterized in that
a deformable energy absorbing bracket (1304, 500) is mounted on the cowl panel (1303) in proximity of the hinge bracket to avoid direct impact of the pedestrian head on the hinge bracket under the vehicle hood (1302).
2. The vehicle hood assembly (1300) as claimed in claim 1, wherein the deformable energy absorbing bracket (1304, 500) is positioned behind fender and the vehicle hood (1302).

3. The vehicle hood assembly (1300) as claimed in claim 1, wherein the deformable energy absorbing bracket (1304, 500) has hat section profile with variable stiffness side walls (501, 502), the side walls (501, 502) have horizontal bent flanges (501a, 502a) extend from the side walls (501, 502) respectively for mounting the deformable energy absorbing bracket (1304, 500) on the cowl panel (1303).

4. The vehicle hood assembly (1300) as claimed in claim 1, wherein impact receiving surface (503) of the deformable energy absorbing bracket (1304, 500) has a slope (?) in downward direction to avoid interaction with the vehicle hood (1302).
5. The vehicle hood assembly (1300) as claimed in claim 1, wherein the side wall (502) of the deformable energy absorbing bracket (1304, 500) has atleast one horizontal slot (502d) and bending profile (502b) to allow plastic deformation of the deformable energy absorbing bracket (1304, 500) during collision to absorb impact energy and deflect the pedestrian head away from hinge bracket.

6. A deformable energy absorbing bracket (500) for absorbing pedestrian head impact energy during collision of vehicle with pedestrian head at vehicle hood hinge bracket region, the deformable energy absorbing bracket (500) comprising:
a first side wall (501) having a plurality of vertical beads (501b), wherein the plurality of beads (501b) provides stiffness to the first side wall (501);
a second side wall (502); and
an impact receiving surface (503) joining the first side wall (501) and the second side wall (502) to form a hat section;
wherein the second side wall (502) has atleast one slot (502d) along length near the impact receiving surface to initiate deformation of the second side wall (502);
wherein the second side wall (502) has a bending profile (502b) to initiate bending of the deformable energy absorbing bracket (500) during collision of the vehicle with the pedestrian head to absorb impact energy.

7. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the second side wall (502) has atleast one notch (502c) to allow additional deformation of the deformable energy absorbing bracket (500) during collision.
8. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the bending profile (502b) of the second side wall (502) allows bending and deformation of the deformable energy absorbing bracket (500) towards the second wall (502) to absorb the impact energy and to deflect the pedestrian head away from the vehicle hood hinge bracket.

9. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the deformable energy absorbing bracket (500) has horizontal bent flanges (501a, 502a) extend from the first side wall (501) and the second side wall (502), respectively, for mounting on cowl panel of the vehicle behind fender and vehicle hood.

10. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the first side wall (501) is stiffer than the second side wall (502) to avoid complete deformation of the deformable energy absorbing bracket (500) in vertical downward direction during collision and to deflect pedestrian head away from the vehicle hood hinge bracket.

11. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the impact receiving surface (503) matches with inner profile of the vehicle hood and does not interact with the inner profile of the vehicle hood before collision.

12. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the deformable energy absorbing bracket (500) is manufactured by combination of stamping, punching, and bending operations.

13. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the deformable energy absorbing bracket (500) can be made from one of steel, aluminum, and thermoplastic.

14. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the deformable energy absorbing bracket (500) can be positioned at any place under the vehicle hood on the cowl panel.

15. The deformable energy absorbing bracket (500) as claimed in claim 6, wherein the deformable energy absorbing bracket (500) is mounted on the cowl panel by means of bolts, spot welding, and CO2 welding.
, Description:A DEFORMABLE ENERGY ABSORBING BRACKET IN VEHICLE HOOD HINGE REGION FOR PEDESTRIAN SAFETY
FIELD OF INVENTION:
[001] The present subject matter described herein, relates to an impact energy absorber for hood of vehicle, and, in particular, to an impact energy absorber in vehicle hood hinge region to absorb impact energy thus protecting head of pedestrian and reducing injury to pedestrian upon impact. In more particularly, the present subject matter relates to structure of an impact energy absorber provided in the region of the vehicle hood hinge for reducing pedestrian head injury during collision of pedestrian head with hood/bonnet of the vehicle.
BACKGROUND AND PRIOR ART:
[002] A hood of vehicle is provided at front end of the vehicle to cover the engine compartment of the vehicle. The hood contributes in adding aesthetics to the vehicle. Generally, the hood is mounted on the front portion of the vehicle with hinges at two ends, i.e., right side and left side. There can be two types of hinges, i.e., single joint hinge and multi joint hinge.
[003] The hood protects head of pedestrian from direct hitting with hard components, such as engine, battery, etc. in the engine compartment. When the vehicle hits the pedestrian from front, the vehicle impacts knee, leg, and femur region of the pedestrian. The frontal impact may elevate and/or flip the pedestrian such that the pedestrian's head strikes the vehicle's hood or windshield. The head impact with the hood or windshield may be fatal if the head suffers high energy impact. When the pedestrian is flipped on the hood of the vehicle, head of the pedestrian hits indirectly via the hood against a hard member, such as an engine, battery, cooling system, junction box, and hood hinge that is provided at least partly below the hood of the vehicle. Magnitude of the head impact injury depends on the area of impact on the front part of the vehicle. Further, the area of impact is influenced by many components, such as outer panel of hood, inner panel of hood, hinge reinforcement of hood, hinge region, fender, wiper system, and cowl area.
[004] Fig. 1 and 2 illustrate hood hinge assembly of hood hinge region of the vehicle as known in the art. The hood of vehicle is generally a closure which is placed over engine compartment. Further, rear end of the vehicle hood is connected to the vehicle body by special hood hinges. The hinge assembly has collapsible hinge bracket 101 and hinge arm 102. The collapsible hinge bracket 101 is mounted on lower front base 105 of the vehicle body, specifically cowl panel. The hinge arm 102 is attached to the lower part of the vehicle hood 104. The hinge arm 102 is mounted on the inner panel of the hood 104 with mounting bolts 103 at plurality of locations, specifically, at two locations. The collapsible hinge bracket 101 is pivotally connected with the hinge arm 102 to allow up and down movement along the pivot axis. During the head impact of the pedestrian on the area of hinge on the hood of vehicle, the impact force pushes the hood in downward direction for absorption of impact force. The collapsible bracket 101 collapse to absorb the impact energy.
[005] Fig. 3 illustrates hood hinge assembly with space between hood and vehicle body to absorb impact energy during head impact of the pedestrian with hood hinge region of the vehicle as known in the art. In another structure of the vehicle hood, the hood of vehicle is generally mounted to the vehicle body by normal hood hinge assembly. The hinge assembly has non-collapsible hinge bracket 201 and hinge arm 202. The non-collapsible hinge bracket 201 is mounted on lower front base 205 of the vehicle body, specifically cowl panel. The hinge arm 202 is positioned in between upper and lower part of the vehicle hood 204. The hinge arm 202 is mounted on the inner panel of the vehicle hood 204 with mounting bolts 203 at plurality of locations, specifically, at two locations. The non-collapsible hinge bracket 201 is pivotally connected with the hinge arm 202 to allow up and down movement along the pivot axis. During the head impact of the pedestrian near the area of hinge on the hood of vehicle, the impact force pushes the hood in downward direction for absorption of impact force. In order to absorb the head impact energy, there is a gap 206 provided in between the lower surface of the inner panel of vehicle hood 204 and the vehicle body 205. However, the gap 206 with vehicle body 205 is very less and it restrict downward movement of the hinge arm 202 and head of the pedestrian hits the hard component with high impact force magnitude. Due to low impact energy absorbing capabilities of the present hinge assembly, the head of the pedestrian incurs injuries with high injury values.
[006] Nowadays, the regulation on pedestrian protection mandates that the vehicle hood be configured to attenuate injury to the pedestrian when the pedestrian is struck by the vehicle and fallen on the hood.
[007] Figure 4a, 4b, and 4c illustrates situation when pedestrian head hits the vehicle hood in conventional vehicle hood region. When the pedestrian head 404 strikes the vehicle at hood hinge location 403 over the vehicle hood 402 at vehicle front end 401, the contact of the pedestrian head 404 with high kinetic energy on the hood hinge bracket causes high head injuries. Figure 4a shows the pedestrian head 404 at first contact point with the vehicle hood 402 at 0ms of impact. Figure 4b shows contact between the pedestrian head 404 and the hood hinge location 403 at 9ms of the impact. As shown in the figure 4c, the pedestrian head 404 hits the hood hinge location 403 and cowl area with high kinetic energy which causes severe injuries to the pedestrian head 404.
[008] In order to satisfy the regulation, several systems have been proposed for protecting the pedestrian head during the impact. In one system, a sufficient gap between the vehicle hood member and its underlying components is suggested to absorb impact energy. However, the gap between the vehicle hood and vehicle body above the threshold limit is difficult and gives the vehicle design constraints, such as aerodynamics and styling. In another suggested system, a deformable collapsible hinge bracket is provided in the hinge assembly for reducing the impact of the pedestrian head on area of the vehicle hood hinge.
[009] Pedestrian safety being an important concern with an ever increasing number of vehicles on roads which thereby forces government to bring Pedestrian safety regulation norms. Hood hinge area is one of the most critical areas to meet the HIC (Head Injury Criteria). It becomes more challenging when the same is to be incorporated in existing vehicle structure ensuring minimum changes to surrounding part structure. The current structure of the hood does not comply with required HIC in hinge region. Further, there is no sufficient space available for hinge arm movement on impact. Due to small gap between the lower part of the hood and the vehicle body, the head of the pedestrian directly hits the hinge arm onto the panel leading to increased injury values. The biggest problem in the existing vehicle structures is to make them safe for pedestrian without changing the layout and structure of the vehicle. Another challenge is to maintain the cost and weight of the vehicle while ensuring safety of the pedestrian head.
[0010] To reduce or eliminate the possibility of severe injury resulting from a pedestrian hood strike or to reduce head injury, several systems have been suggested to increase the gap between the lower part of the hood and the vehicle and provide a collapsible bracket in the hinge assembly. However, these systems require changes in aerodynamics/styling intent as well as the rigidity of the vehicle hood. Further, these systems require structural changes in the vehicle which increases the cost and rigidity of the vehicle. There is a small gap between the vehicle hood and the hinge bracket. Therefore, it is required to divert the impactor away from the hinge bracket location to avoid hitting with stiff hinge bracket. Accordingly, it is desirable to develop an impact energy absorber that overcomes the foregoing and other problems and disadvantages as mentioned. Therefore, there is a need in the art to provide an impact energy absorber that can be more simple and inexpensive, and which can be placed in the existing structures of the vehicle to fulfill the regulations of the pedestrian safety.
OBJECTS OF THE INVENTION:
[0011] The principal object of the present invention is to provide an impact energy absorber to absorb head impact energy on hood of the vehicle and reduces injuries to pedestrian head.
[0012] Another object of the present subject matter is to provide a deformable energy absorber or energy absorbing bracket which deforms in specified manner/controlled manner/predetermined manner to absorb the impact energy during head impact with the hood of the vehicle.
[0013] Another object of the present subject matter is to provide a deformable energy absorbing bracket adjacent to mounting area of hinge bracket in between cowl panel and the vehicle hood.
[0014] Another object of the present subject matter is to provide an impact energy absorber which deforms in a specified manner to absorb head impact energy and prevents direct hitting of the pedestrian head on the hinge bracket assembly of the vehicle hood and reduce the magnitude of injuries to the pedestrian head.
[0015] Yet another object of the present invention is to provide an impact energy absorber which is simple and inexpensive, and efficiently absorbs the head impact energy on hood hinge area without causing major injury to the pedestrian head.
[0016] Yet another object of the present invention is to provide an impact energy absorber which can be implemented in existing vehicles without any major structural modifications.
[0017] Yet another object of the present invention is to make existing vehicles pedestrian safe by implementing the impact energy absorber.
SUMMARY OF THE INVENTION:
[0018] The subject matter disclosed herein relates to a deformable energy absorbing bracket under vehicle hood assembly for reducing the impact of pedestrian head injuries during impact of the pedestrian head with vehicle hood, in particularly, to vehicle hood hinge bracket region which is one of the hardest joint on the vehicle hood area. The vehicle hood assembly has vehicle hood, two hood hinge assemblies and a deformable energy absorbing bracket. The vehicle hood is pivotally connected with the vehicle body through the hinge assembly for up and down movement about horizontal pivot axis to open and close position of engine compartment in the vehicle, respectively. The hinge assembly has hinge arm and non-collapsible hinge bracket. The non-collapsible hinge bracket is mounted on the vehicle body, specifically cowl top panel. The hinge arm is mounted on the vehicle hood inner panel from one end through hinge mounting bracket and pivotally connected with the non-collapsible bracket at other end. Similarly, another hinge assembly is provided on the other end of the vehicle hood to allow pivot movement of the vehicle hood. The deformable energy absorbing bracket is mounted on the cowl panel behind fender and the vehicle hood. The deformable energy absorbing bracket is provided in between the vehicle hood and the cowl panel. When head of the pedestrian hits the hood hinge area, the deformable energy absorbing bracket receives impact energy from the fender and the vehicle hood and deforms in specified manner to absorb impact energy applied by the head. While absorbing the head impact energy during collision, the deformable energy absorbing bracket deforms and absorbs impact energy and prevents hitting of head to hinge bracket, thereby reducing the magnitude of head injuries. The deformable energy absorbing bracket has a hat section profile with one side wall having high stiffness compared to other. The side wall having low stiffness has horizontal slot and bending profile to initiate bending and deformation of the deformable energy absorbing bracket in one direction to absorb head impact energy efficiently and to deflect the pedestrian head away from the hard points. The deformable energy absorbing bracket absorbs the head impact energy at the hood hinge bracket region and reduces the injuries cause to head of the pedestrian.
[0019] In another embodiment of the present subject matter, structure of the deformable energy absorbing bracket is illustrated. The deformable energy absorbing bracket is in ‘n’ shape or in hat section shape and made from a single sheet material. The deformable energy absorbing bracket has two vertical side walls, i.e., first side wall and the second side wall and one horizontal impact receiving surface which joins the two side walls to define the hat section. In the deformable energy absorbing bracket structure, the first side wall has high stiffness as compared to the second side wall. The second side wall has horizontal slot along length of the deformable energy absorbing bracket and a bending profile to initiate bending of the second side wall upon impact. During the collision, the second side wall collapse/deform to absorb initial impact due to horizontal slot and further bends according to bending profile to absorb impact energy. The first side wall has a plurality of beads which provide stiffness to the first side wall. The first side wall avoids complete and immediate deformation of the deformable energy absorbing bracket in vertical downward direction during collision. Further, one side wall with less stiffness and other side wall with high stiffness guides bending of the deformable energy absorbing bracket in one direction to allow deflection of the pedestrian head from the hard point under the vehicle hood.
[0020] 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
[0021] 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:
[0022] Fig. 1, and 2 illustrate hood hinge assembly with collapsible bracket to absorb head impact energy during head impact of pedestrian with hood hinge region of the vehicle as known in the art;
[0023] Fig. 3 illustrates hood hinge assembly having non-collapsible hinge bracket with space between hood and vehicle body to absorb impact energy during head impact of the pedestrian with hood hinge region of the vehicle as known in the art;
[0024] Fig. 4a, 4b, and 4c illustrate impact of pedestrian head on the existing vehicles;
[0025] Fig. 5 and 6 illustrate structure of deformable energy absorber, in accordance with an embodiment of the present subject matter;
[0026] Fig. 7 illustrates front view of the deformable energy absorber, in accordance with an embodiment of the present subject matter;
[0027] Fig. 8 illustrates top view of the deformable energy absorber, in accordance with an embodiment of the present subject matter;
[0028] Fig. 9 and 10 illustrate side views showing side faces of the deformable energy absorber, in accordance with an embodiment of the present subject matter;
[0029] Fig. 11 illustrates cross section along AA of the deformable energy absorber of Fig. 10, in accordance with an embodiment of the present subject matter;
[0030] Fig. 12 illustrates mounting of the deformable energy absorber at hood hinge assembly, in accordance with an embodiment of the present subject matter;
[0031] Fig. 13 illustrates pedestrian head impact with the hood hinge assembly having the deformable energy absorber adjacent to hood hinge bracket , in accordance with an embodiment of the present subject matter;
[0032] Fig. 14 illustrates structure of the deformable energy absorber before impact and after impact, in accordance with an embodiment of the present subject matter;
[0033] Fig. 15 illustrates energy absorbed by the deformable energy absorber during impact of the pedestrian head with the hood hinge assembly, in accordance with an embodiment of the present subject matter; and
[0034] Fig. 16 illustrates pedestrian head acceleration comparison with and without the deformable energy absorber, 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 deformable energy absorbing bracket in vehicle hood assembly for reducing the impact of pedestrian head injuries during impact of the pedestrian head with vehicle hood, in particularly, to vehicle hood hinge bracket region which is one of the hardest joint on the vehicle hood area. The vehicle hood assembly has vehicle hood, two hood hinge assemblies and a deformable energy absorbing bracket. The vehicle hood is pivotally connected with the vehicle body through the hinge assembly for up and down movement about horizontal pivot axis to open and close position of engine compartment in the vehicle, respectively. The hinge assembly has hinge arm and non-collapsible hinge bracket. The non-collapsible hinge bracket is mounted on the vehicle body, specifically on cowl top panel. The hinge arm is mounted on the vehicle hood inner panel from one end through hinge mounting bracket and pivotally connected with the non-collapsible bracket at other end. Similarly, another hinge assembly is provided on the other end of the vehicle hood to allow pivot movement of the vehicle hood. The deformable energy absorbing bracket is mounted on the cowl panel behind fender and the vehicle hood. The deformable energy absorbing bracket is provided in between the vehicle hood and the cowl panel. When head of the pedestrian hits the hood hinge area, the deformable energy absorbing bracket receives impact energy from the fender and the vehicle hood and deforms in specified manner to absorb impact energy applied by the head. While absorbing the head impact energy during collision, the deformable energy absorbing bracket deforms and prevents hitting of head to hinge bracket, thereby reducing the magnitude of head injuries. The deformable energy absorbing bracket has hat section profile with one side wall having high stiffness compared to other. The side wall having low stiffness has horizontal slot and bending profile to initiate bending and deformation of the deformable energy absorbing bracket in one direction to absorb head impact energy efficiently and to deflect the pedestrian head away from the hard points. The deformable energy absorbing bracket absorbs the head impact energy at the hood hinge region and reduces the injuries caused to head of the pedestrian.
[0037] In another embodiment of the present subject matter, structure of the deformable energy absorbing bracket is illustrated. The deformable energy absorbing bracket is in ‘n’ shape or in hat section shape and made from a single sheet metal. The deformable energy absorbing bracket has two vertical side walls, i.e., first side wall and second side wall and one horizontal impact receiving surface which joins the two side walls to define the hat section. In the deformable energy absorbing bracket structure, the first side wall has high stiffness as compared to the second side wall. The second side wall has horizontal slot along length of the deformable energy absorbing bracket and a bending profile to initiate bending of the second side wall upon impact. During the collision, the second side wall collapse/deform to absorb initial impact due to horizontal slot and further bends according to bending profile to absorb impact energy. The first side wall has a plurality of beads which provide stiffness to the first side wall. The first side wall avoids complete and immediate deformation of the deformable energy absorbing bracket in vertical downward direction during collision. Further, one side wall with less stiffness and other side wall with high stiffness guides bending of the deformable energy absorbing bracket in one direction to allow deflection of the pedestrian head from the hard point under the vehicle hood.
[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. 5 illustrates structure of deformable energy absorbing bracket, in accordance with an embodiment of the present subject matter. The present deformable energy absorbing bracket 500 is in hat section and made from a single sheet metal. The deformable energy absorbing bracket 500 has two side walls, i.e., first side wall 501, second side wall 502 and one impact receiving surface 503 in between two side walls 501, 502. The impact receiving surface 503 connects the first side wall 501 and the second side wall 502 at upper end portion and defines/forms a hat section. The first side wall 501 is stiffer than the second side wall 502. Therefore, the deformable energy absorbing bracket 500 has variable stiffness at two vertical side walls 501, 502. As shown in the figure 6 and 10, the first side wall 501 has a plurality of vertical beads 501b to provide stiffness to the first side wall 501 in the vertical direction. The plurality of vertical beads 501b is provided to prevent vertical deformation in direction of impact so that the pedestrian head is deflected during the impact and avoid hitting the hinge bracket directly.
[0041] As shown in the figure 5 and 9, the second side wall 502 has atleast one slot 502d in longitudinal direction along length of the deformable energy absorbing bracket 500 to initiate collapsing/deformation of the second side wall 502 during initial impact of the pedestrian head on the vehicle hood. Further, the number of longitudinal slot 502d can be any number depending on the required stiffness of the second side wall 502 and the vertical height of the deformable energy absorbing bracket 500. After the atleast one slot 502d in longitudinal direction, the second side wall 502 has a bending profile 502b in vertical downward direction of the slot 502d to initiate bending of the deformable energy absorbing bracket 500 during impact. The second side wall 502 has atleast one notch 502c in vertical downward direction of the bending profile 502b. The atleast one notch 502c is provided to increase deformation of the deformable energy absorbing bracket 500. Further, number of the notches can be increased depending upon the required stiffness of the second side wall. The combination of the slot, bending profile, and notch on the second side wall 502 and vertical beads on the first side wall 501 allows deformation of the deformable energy absorbing bracket 500 in one direction, i.e., towards the second side wall 502 having low stiffness and deformation of the deformable energy absorbing bracket 500 in one direction allows deflection of the pedestrian head from the hard point under the vehicle hood.
[0042] As shown in the figure 5, 6, 7, and 8, the deformable energy absorbing bracket 500 has hat section profile with variable stiffness side walls 501, 502. The first side wall 501 has horizontal bent flange 501a which extend from side wall 501 in horizontal direction for mounting the deformable energy absorbing bracket 500 on cowl panel of the vehicle. Similarly, the second side wall 502 has a horizontal bent flange 502a which extend from the second side wall 502 in horizontal direction for mounting the deformable energy absorbing bracket 500 on the cowl panel.
[0043] As shown in the figure 9, the impact receiving surface 503 has slope ‘?’ to prevent interaction of hood inner with the deformable energy absorbing bracket 500. Further, the angle ‘?’ of the slope is dependent on the hood inner profile. It matches with the hood inner profile and guides deformation of the deformable energy absorbing bracket 500 upon impact on the vehicle hood. During the impact, the vehicle hood inner transfers impact load on the sloped profile of the deformable energy absorbing bracket 500 for deformation.
[0044] Figure 10 shows side view of the first side wall 501 with cross section AA. Figure 11 illustrates the cross section view along AA line of the figure 10. The cross section view clearly illustrates the longitudinal slot 502d, the bending profile 502b, and the horizontal flange 502a on the second side wall 502. As shown in the figure 11, the second side wall 502 deforms according to the slot and bending profile in one direction. The first side wall 501 has vertical beads which prevent bending and deformation of the first side wall upon impact. As shown in the figure, the structure of the deformable energy absorbing bracket 500 is divided in two parts, i.e., side wall 501 and side wall 502. The second side wall 502 of bracket is designed with the intention of achieving higher deformation to increase energy absorption capabilities whereas the first side wall 501 is intended to be stiff and should be able to prevent direct pedestrian head hitting with the stiff hinge bracket.
[0045] However to prevent hitting of pedestrian head on hinge bracket, side wall 501 of absorber bracket is made stiffer by addition of beads in vertical direction. In case side wall 501 is not made stiffer, the energy absorbing bracket will collapse completely and this will result in hitting of pedestrian head on hinge bracket. Stiffening of side wall 501 helps to deflect the impactor away from the hinge bracket thereby preventing the head from hitting the hinge bracket.
[0046] Figure 12 illustrates positioning and mounting of the deformable energy absorbing bracket 500 on the cowl panel, in accordance with an embodiment of the present subject matter. The deformable energy absorbing bracket 500 is designed to prevent head injury in the event of pedestrian collision with motor vehicle. Further, location of the energy absorbing bracket is shown in fig.12. The deformable energy absorbing bracket 500 is mounted to the cowl panel via the horizontal flanges 501a, 502a. Further, the one flange can be spot welded and other flange can be bolted with cowl panel.
[0047] As shown in the figure 13, the vehicle hood assembly 1300 is explained. The vehicle hood assembly 1300 has a fender 1301, vehicle hood 1302, a cowl panel 1303, and deformable energy absorbing bracket 1304 (as of deformable energy absorbing bracket 500). Further, the vehicle hood 1302 is mounted on the cowl panel 1303 by a hinge arm assembly or hinge bracket on both sides. The vehicle hood 1302 moves up and down about the horizontal pivot axis. The hinge bracket is a hard part which causes severe injuries to the pedestrian head if no protection is provided. The present subject matter provides a deformable energy absorbing bracket 1304 which is positioned in between the vehicle hood 1302 and the cowl panel 1303 to absorb the impact energy and deflect the pedestrian head away from the hinge bracket. The deformable energy absorbing bracket 1304 is mounted on the cowl panel 1303 in proximity of the hinge bracket under the vehicle hood 1302. The deformable energy absorbing bracket 1304 is positioned behind fender and the vehicle hood 1302. The deformable energy absorbing bracket 1304 is positioned such that the impact energy is directly transferred to the bracket through fender thus preventing head from contacting hard points, such as hinge bracket under the hood.
[0048]
[0049] Figure 14 illustrates structure of the deformable energy absorber before impact and after impact, in accordance with an embodiment of the present subject matter. Under the impact, the deformable energy absorbing bracket deforms and absorbs the impact energy exerted by the head impactor or the pedestrian head. Before the impact, the deformable energy absorbing bracket (1502) is straight and after the impact, the deformable energy absorbing bracket (1504) is deformed in one direction towards the side having low stiffness.
[0050] Fig 15 shows the impact energy absorbed by the present deformable energy absorbing bracket. The deformable energy absorbing bracket absorbs approximate 24% of the total energy absorbed by the vehicle which has helped to reduce the pedestrian head injury.
[0051] Fig. 16 illustrates pedestrian head acceleration comparison with and without the deformable energy absorber, in accordance with an embodiment of the present subject matter. In the absence of energy absorbing bracket, the pedestrian head deforms the fender and vehicle hood and hits the hinge bracket causing severe head injury. 1701 indicates the sharp rise in acceleration due to head impacting the hinge bracket, due to sharp rise in acceleration, the pedestrian head receives severe injuries. With the addition of the deformable energy absorbing bracket, the impact energy is transferred from fender to energy absorbing bracket. The second side wall 502 of the deformable energy absorbing bracket 500 deforms gradually and absorbs the impact energy whereas the first side wall 501 of the deformable energy absorbing bracket 500 resists impactor from hitting the hinge bracket.
[0052] The deformable energy absorbing bracket can be manufacture easily by combination of stamping, punching and bending operation.
[0053] The deformable energy absorbing bracket can be made of steel (any grade), Aluminum or thermoplastics with equivalent stiffness. Stiffness can also be managed by varying the thickness of energy absorbing bracket, size and shape of holes and position of beads.
[0054] The deformable energy absorbing bracket can be mounted to the vehicle by means of bolts, spot weld or CO2 welding.
[0055] The deformable energy absorbing bracket is compact in design and can easily be accommodated in vehicle.
[0056] The orientation and position of slots can be varied as per the performance requirement.
[0057] Energy absorbing bracket help to significantly reduce the pedestrian head injury (approx. 23%) in the event of collision of pedestrian head with vehicle hood.
[0058] The present deformable reinforcement reduces Head Injury Criteria (HIC) value at the hood hinge region. The structure of the present deformable reinforcement allow better energy absorbing capabilities during head impact at the hood hinge region. The deformable reinforcement plastically deforms in a specified manner according to the plurality of slots and bending portion to provide better HIC values.
[0059] It is easy to manufacture and assemble the present deformable energy absorbing bracket in the existing vehicles. There is no requirement to change the current structure of the existing vehicles so there is no modification cost. Further, there is no requirement to change the current layout. The present deformable energy absorbing bracket can be implemented in the existing vehicle to make the existing vehicles safe for pedestrian. The present deformable energy absorbing bracket in the vehicle hood assembly meets the required HIC value for complying pedestrian safety regulations. The present deformable energy absorbing bracket is light weighted so addition of deformable energy absorbing bracket does not add too much extra weight to the vehicle. Further, the present deformable energy absorbing bracket does not need any special welding facilities. Therefore, the present deformable energy absorbing bracket can be implemented in the existing vehicle using existing facilities.
[0060] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. Plural structural components or steps can be provided by a single integrated structure or step. Alternatively, a single integrated structure or step might be divided into separate plural components or steps. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.
[0061] 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.