DESC:FIELD
The present invention generally relates to automobiles and in particular to an impact absorbing vehicular hood, which facilitates protection to a body colliding with the vehicle.
DEFINITIONS
Vehicle hood: A hood or bonnet is a hinged cover over the engine of motor vehicles, which facilitates selective access to the engine compartment (or trunk in case of rear-engine and mid-engine vehicles), for maintenance and repair.
Collapsible bracket: It refers to a bracket/structure that is intentionally made to deform during a collision, and hence assist in energy absorption by means of axial crush and bending phenomena.
Bump stop: A “bump-stop” is an arrangement that prevents a hood assembly from over slam and from damaging interface parts such as head lamp. Moreover, this arrangement prevents the hood assembly from hard hitting while closing the vehicle hood. It also helps in maintaining gap values of the hood assembly with interface parts.
Colliding body: An external object, such as a pedestrian, colliding with the vehicle is referred to as a colliding body.
Secondary collision: After a moving vehicle has collided against a colliding body, the colliding body may sometimes collide against a hood of the vehicle. This collision of the colliding body with the hood of the vehicle is called a “secondary collision”.
Head Injury Criteria (HIC): The Head Injury Criterion (HIC) is a measure of the likelihood of head injury arising from an impact/collision. The HIC can be used to assess the safety related to vehicles, personal protective gear, and sport equipment.
SPCC material: SPCC is a quality symbol that applies to a cold rolled steel. SPCC designates the steel for commercial use according to Japanese Industrial Standards (JIS). SPCC quality steel sheets and coils are used in automotive and electrical applications.
EC 78/2009: EC 78/2009 (Protection of Pedestrians and Other Vulnerable Road Users) is a regulation on the type-approval of Motor Vehicles with regard to the Protection of Pedestrians and Other Vulnerable Road Users.
BACKGROUND
Vehicles have become a very important part of our daily life. However, vehicle related accidents are also on the rise. Around 12 lakh people are killed annually in vehicular crashes worldwide, of which about 75% of the people killed are pedestrians.
One way to reduce vehicle related accidents is by educating people. Another way is to focus on traffic control systems and make them robust. Still another way may be by developing vehicles that reduce the likelihood of fatal injuries to pedestrians in the event of a collision. Attempts have been made to design and redesign various parts of a vehicle that come into contact with an external colliding body during an accident, such as the bumper, the hood (bonnet), and the windshield, so that the energy of collision could be better absorbed and dissipated during an accident, without compromising too much on the structural integrity of the vehicle.
To launch a vehicle (such as a car) in any country, the vehicle has to adhere to crash regulations laid down by the country laws. More specifically, the vehicle to be launched has to adhere to pedestrian safety norms as an integral part of the vehicle. EC 78/2009, laid down by the European Union, is one such important regulation that caters to the safety of pedestrians. In accordance with EC 78/2009, the ‘Head Injury Criteria’ (HIC) is used to assess the severity of pedestrian injury when an impacting body that resembles closely to a human head is forced to collide onto the vehicle, specifically on the hood and windscreen of the vehicle. A high value of HIC indicates higher injury severity and vice-versa.
It is observed that the HIC value is comparatively higher when the colliding body strikes against the hood of the vehicle, at and around the hinge area and the bump stop area. Higher HIC value can be attributed to the relatively rigid nature of these areas on the hood. More specifically, high HIC value on the hood around these regions can be due to the rigid nature of the bump stop, the limited space for deformation, and absorption and dissipation of the energy by the hood, in the event of a collision. Because of this, it is difficult to reduce the HIC value at and around these regions.
It is observed that by altering the stiffness of the hood (inner hood and outer hood), by varying the thickness and material properties, there is a marginal decrease in the HIC value. In accordance with EC 78/2009, the HIC value should be less than 1700. Attempts have been made to reduce the HIC value of the hood at and around the bump stop area and the hinge area. In particular, these impact zones can be avoided by configuring the vehicle hood such that the impact zone is relocated towards the center of the hood, thereby achieving an HIC value of less than 1700 at and around the bump stop and the hinge areas on the vehicle hood.
Another solution towards the aforementioned HIC issue is to increase clearance between a hood inner and the bump stop, thereby configuring sufficient space for the hood inner to absorb and dissipate the energy of collision by causing controlled deformation thereof. Nonetheless, none of the above solutions have provided an effective and fool-proof solution to the issues discussed above.
Therefore, there is a need to provide a vehicle hood that can absorb and dissipate the collision energy comparatively more effectively.
OBJECTS
Some of the objects of the present invention are aimed to ameliorate one or more problems of the prior art or to at least provide a useful alternative are described herein below:
It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
An object of the present disclosure is to provide a vehicle hood that is configured to absorb and dissipate the collision energy during a collision with an external colliding body;
Still another object of the present disclosure is to provide a vehicle hood that is configured to absorb and dissipate the collision energy due to a secondary collision of the colliding body;
Yet another object of the present disclosure is to provide a vehicle hood that is configured to absorb and dissipate the collision energy, thereby lessening the impact reaction received by the colliding body;
Another object of the present disclosure is to provide a vehicle hood with reduced HIC value;
Another object of the present disclosure is to provide a vehicle hood with a reduced HIC value at and around the bump stop area of the hood;
Another object of the present disclosure is to provide a vehicle hood with a reduced HIC value at and around the hinge area of the hood; and
Other objects and advantages of the apparatus of the present disclosure will be more apparent from the following description, which are not intended to limit the scope of the present disclosure.
SUMMARY
Described herein is a vehicle hood for a vehicle comprising a hood inner and a hood outer, wherein a cavity is formed between an operative outer surface of said hood inner and an operative inner surface of said hood outer, and a collapsible bracket disposed on said hood inner inside said cavity, around at least one of a bump stop area and a headlamp area of said vehicle, wherein said collapsible bracket has a proximal end attached to said hood inner towards a free moving end of said vehicle hood and a distal end attached to said hood inner towards a hinged end of said vehicle hood.
In one embodiment, said collapsible bracket comprises a central substantially flat region ‘a’, a first transition region ‘b’ extending from said central region and sloping downwards when viewed from an operatively above position, a first flange ‘c’ extending from said transition region ‘b’ having a substantially curved sub-profile, a second transition region ‘d’ extending from said central region ‘a’ and sloping downwards when viewed from an operatively above position, and a second flange ‘e’ extending from said second transition region ‘d’ having a substantially flat sub-profile.
In yet another embodiment, said collapsible bracket includes two grooves extending inwardly from a surface of said central region ‘a’ and orthogonal to a longitudinal axis of said collapsible bracket.
In one more embodiment, said first transition region ‘b’ includes a first pair of dimples ‘i’ extending inwardly from an operative top surface of said transition region ‘b’.
In one embodiment, said second transition region ‘d’ includes a second pair of dimples ‘ii’ extending inwardly from an operative top surface of said transition region ‘d’.
The collapsible bracket can be made of SPCC material such as commercial quality cold rolled steel. However, any other similar material may also be used.
In accordance with one embodiment, said first flange ‘c’ is welded on a horizontal and curved surface of said hood inner, while said second flange ‘e’ is welded on a flat vertical wall of said hood inner, wherein said sub-profiles of said first flange ‘c’ and said second flange ‘e’ are complimentary to a profile of said hood inner.
In another embodiment, said central region ‘a’ of said collapsible bracket is glued to said hood outer, wherein a sealant is applied in said two grooves.
In one embodiment, said sealant is applied in said two grooves such that a gap is formed between said central region ‘a’ of the collapsible bracket and said inner surface of the hood outer.
BRIEF DESCRIPTION OF DRAWINGS
The vehicle hood with a collapsible bracket will now be described with the help of the accompanying drawings in which:
FIG. 1 illustrates a top view of a conventional vehicle hood;
FIG. 2A illustrates a top view of a vehicle with a vehicle hood provided with collapsible brackets on a hood inner on the bump stop areas or on the headlamp areas, in accordance with an embodiment of the present disclosure;
FIG. 2B illustrates an isometric view of the vehicle of FIG. 2A showing a hood inner of the vehicle hood provided with a collapsible bracket on the bump stop areas or on the headlamp areas, in accordance with an embodiment of the present disclosure;
FIG. 2C illustrates a detailed view of a section of the hood inner of the vehicle hood with a collapsible bracket in accordance with an embodiment of the present disclosure;
FIG. 3A illustrates an isometric view of the collapsible bracket in accordance with an embodiment of the present disclosure;
FIG. 3B illustrates another isometric view of the collapsible bracket of FIG. 3A in accordance with an embodiment of the present disclosure;
FIG. 4 illustrates a cross-sectional side view of a vehicle with a vehicle hood with a collapsible bracket disposed on the hood inner, below the hood outer, and its position relative to other parts of the vehicle;
FIG. 5A to FIG. 5D illustrate finite element (FE) simulation images of a colliding body against the collapsible bracket disposed on the hood inner of the vehicle hood;
FIG. 6 illustrates a cut section of the finite element model of a vehicle along with a colliding body positioned on the headlamp or bump stop area of the vehicle;
FIG. 7A is a graph depicting the Head Injury Criteria (HIC) comparison between vehicles with and without the collapsible bracket on the bump stop area of the vehicle; and
FIG. 7B is a graph depicting the Head Injury Criteria (HIC) comparison between vehicles with and without the collapsible bracket on the headlamp area of the vehicle.
DETAILED DESCRIPTION
A vehicle hood with a collapsible structure/bracket will now be described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
FIG. 1 illustrates a top view of a vehicle 100 with a conventional vehicle hood 105. The conventional vehicle hood 105 as depicted in FIG. 1 is shown in a closed position and covers the engine compartment (not shown in the figure). Typically, a hinged end 101 of the vehicle hood 105 near the windshield is provided with hinges (not shown in the figure) so that the vehicle hood 105 pivots about the hinged end 101 and can be opened by lifting a free moving end 102 of the hood to access the engine of the vehicle for maintenance and repair thereof. Further, numerals 103a and 103b indicate the bump stop area and/or the headlamp area of the vehicle. It is observed that in this conventional vehicle hood design, the HIC value is high when a colliding body collides against the vehicle hood 105 at and around the bump stop area 103a and the headlamp area 103b, which is attributed to the relatively rigid nature of these areas. Moreover, the HIC value at and around these locations of the vehicle hood 100 is difficult to reduce owing to the inherent rigidity of these areas of the hood.
FIG. 2A illustrates a top view of a vehicle 200 with a vehicle hood 205 with collapsible structures or brackets 204a and 204b disposed on a hood inner 205 on the bump stop areas 203a, and/or the headlamp areas 203b in accordance with an embodiment of the present disclosure. The vehicle hood 200 covers the engine compartment (not shown in the figure). Typically, a hinged end 201 of the vehicle hood 200 near the windshield is provided with hinges (not shown in the figure) so that the vehicle hood 200 pivots about the hinged end 201 and can be opened by lifting a free moving end 202 of the hood to access the engine of the vehicle for maintenance and repair thereof. Further, numerals 203a and 203b indicate the bump stop area and/or the headlamp area of the vehicle. More specifically, in accordance with the present disclosure, the vehicle hood 200 of the vehicle comprises of a hood outer and a hood inner (illustrated in FIG. 4), wherein the profiles of the hood outer and the hood inner are such that a cavity S is formed between an operative inner surface of hood outer and an operative outer surface of the hood inner. In accordance with the present disclosure, the collapsible brackets 204a and 204b are disposed in the cavity S formed between the operative inner surface of hood outer and the operative outer surface of the hood inner, and on the bump stop areas and/or the headlamp areas (203a, 203b).
FIG. 2B illustrates an isometric view of the vehicle of FIG. 2A showing a hood inner 205' provided with the collapsible bracket 204a on the bump stop areas and/or the headlamp areas 203a and 203b, in accordance with an embodiment of the present disclosure. Likewise, FIG. 2C illustrates a detailed view of the hood inner 205' with the collapsible brackets 204a or 204b, collectively referred to as brackets 204, disposed thereon in accordance with an embodiment of the present disclosure. Each of the collapsible brackets 204 has a proximal end P, that is proximal to the free moving end 202, and a distal end D that is disposed away from the free moving end 202 towards the windshield (see FIGS. 2A and 2B).
FIG. 3A illustrates an isometric view of a collapsible bracket 204 in accordance with an embodiment of the present disclosure. The collapsible bracket 204 has a unique characteristic profile along the ends D and P. In accordance with the present disclosure, the collapsible bracket 204 comprises a central substantially flat region ‘a’, a first transition region ‘b’ extending from the central region ‘a’ such that when the collapsible bracket is viewed from above, the transition region ‘b’ appears to be sloping downwards, a first flange ‘c’ that extends from the transition region ‘b’ having a substantially curved sub-profile, a second transition region ‘d’ extending from the central region ‘a’ such that when the collapsible bracket is viewed from above, the transition region ‘b’ appears to be sloping downwards, and a second flange ‘e’ that extends from the second transition region ‘d’ and having a substantially flat sub-profile.
In an embodiment, the central region ‘a’ of the collapsible bracket 204 includes two grooves ‘f’ extending inwardly from the surface of the central region ‘a’ and orthogonal to the longitudinal axis of the collapsible bracket 204. In accordance with an exemplary embodiment of the present disclosure, the collapsible bracket 204 is made of SPCC grade material, such as SPCC steel. Further, in an embodiment, the first transition region ‘b’ features a first pair of dimples ‘i’ extending inwardly from the operative top surface of the transition region ‘b’ for providing strength to the collapsible bracket. Likewise, the second transition region ‘d’ features a second pair of dimples ‘ii’ extending inwardly from the operative top surface of the transition region ‘d’ for providing strength to the collapsible bracket.
FIG. 3B illustrates another isometric view of the collapsible bracket 204 of FIG. 3A in accordance with an embodiment of the present disclosure.
FIG. 4 illustrates a cross-sectional side view of the vehicle 200 with a vehicle hood 205 having the collapsible bracket 204 disposed on the hood inner 205' and below the hood outer 205? and its position being relative to other parts of the vehicle. More specifically, the collapsible bracket 204 is disposed in the cavity S formed between the operative inner surface of the hood outer (205?) and the operative outer surface of the hood inner 205' and on the bump stop areas and/or the headlamp areas 203a and 203b.
In accordance with an embodiment of the present disclosure, the first flange ‘c’ is welded on a horizontal and curved surface of the hood inner 205' whereas the second flange ‘e’ is welded on a flat vertical wall of the hood inner 205', wherein profiles of the first flange ‘c’ and the second flange ‘e’ of the collapsible bracket 204 are complimentary to a profile of the hood inner 205'.
In accordance with the present disclosure, the central region ‘a’ of the collapsible bracket 204 is glued to the hood outer 205? by means of glue, preferably a mastic sealant. More specifically, the central region ‘a’ of the collapsible bracket 204 is glued to the hood outer 205? by means of the mastic sealant, wherein the sealant is applied in the two grooves ‘f’ extending inwardly from the surface of the central region ‘a’ and orthogonal to the longitudinal axis of the collapsible bracket 204.
In accordance with one embodiment of the present disclosure, the sealant is applied in the two grooves such that a gap of 1 mm to 10 mm, preferably a gap of 3 mm is formed between the central region ‘a’ of the collapsible bracket 204 and the inner surface of the hood outer 205?.
Thus, the hood outer 205? is reinforced by the central region ‘a’ of the collapsible bracket 204. Further, a space is configured below the central region ‘a’ of the collapsible bracket 204 that facilitates a controlled deformation of the collapsible bracket 204 when the colliding body collides with the hood outer 205?. This controlled deformation permits absorption of the collision energy by the collapsible bracket 204. This feature of the collapsible bracket 204 lessens the damage and/or injury to the colliding body that may be a head of a pedestrian.
FIG. 5A to FIG. 5D illustrate simulation images of a colliding body ‘O’ against the collapsible bracket disposed on the hood inner 205' of the vehicle hood in accordance with the embodiments of the present disclosure. It is evident from the images that the central region ‘a’ of the bracket absorbs the collision energy by getting deformed in a controlled manner.
FIG. 6 illustrates a cut section of the finite element model of a vehicle along with a colliding body ‘O’ positioned on headlamp/bump stop area of the vehicle.
FIG. 7A is a graph depicting the Head Injury Criteria (HIC) comparison between a vehicle with the collapsible bracket (shown by line B) and without the collapsible bracket (shown by line A) on the bump stop area of the vehicles; and FIG. 7B is a graph depicting the Head Injury Criteria (HIC) comparison between a vehicle with the collapsible bracket (shown by line B) and without the collapsible bracket (shown by line A) on the headlamp area of the vehicles, the collapsible bracket being disposed between the hood outer and hood inner on headlamp/bump stop area of the vehicles. It was observed in the first case (FIG. 7A) that there is a considerable reduction in the HIC value (around 127 points), while in the second case (Fig. 7B), the HIC value is decreased sufficiently (around three points), showing good improvement towards the objective of achieving lower HIC.
In particular, the simulation shows that the HIC value of the hood with the collapsible bracket disposed on the hood inner, on the bump stop and/or headlamp area is less than 1700 and is typically found to be 1503 as compared to the hood without collapsible bracket, wherein the HIC value is found to be 1681. Thus, the provision of the collapsible bracket aids in reducing the HIC value far below the cutoff value of 1700, as specified by EC 78/2009 regulation.
Though, the present disclosure recites a specific profile of the collapsible bracket, any other possible shape of the collapsible bracket is possible subject to the condition that the collapsible bracket has a profile that facilitates the absorption and dissipation of the collision energy, when the colliding object collides with the hood of the vehicle, by getting deformed in a controlled manner. Further, the collapsing bracket has sufficient space so that it can get deformed in a controlled manner.
The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
TECHNICAL ADVANCES AND ECONOMICAL SIGNIFICANCE
The vehicle hood with a collapsible bracket in accordance with the present disclosure described herein above has several technical advantages including but not limited to the realization of the following:
• High tendency to absorb collision energy during a collision with an external colliding body;
• Low HIC value at critical points on the hood, such as at and around the bump stop area or the headlamp area of the hood; and
• Avoids serious injuries to pedestrians.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. ,CLAIMS:1. A vehicle hood (205) for a vehicle (200) comprising:
a hood inner (205') and a hood outer (205?), wherein a cavity (S) is formed between an operative outer surface of said hood inner and an operative inner surface of said hood outer; and
a collapsible bracket (204) disposed on said hood inner inside said cavity (S), around at least one of a bump stop area (203a) and a headlamp area (203b) of said vehicle, wherein said collapsible bracket has a proximal end (P) attached to said hood inner towards a free moving end (202) of said vehicle hood and a distal end (D) attached to said hood inner towards a hinged end (201) of said vehicle hood.
2. The vehicle hood as claimed in claim 1, wherein said collapsible bracket (204) comprises a central substantially flat region (a), a first transition region (b) extending from said central region and sloping downwards when viewed from an operatively top position, a first flange (c) extending from said transition region (b) having a substantially curved sub-profile, a second transition region (d) extending from said central region (a) and sloping downwards when viewed from an operatively top position, and a second flange (e) extending from said second transition region (d) having a substantially flat sub-profile.
4. The vehicle hood as claimed in claim 1, wherein said collapsible bracket (204) includes two grooves (f) extending inwardly from a surface of said central region (a) and orthogonal to a longitudinal axis of said collapsible bracket.
5. The vehicle hood as claimed in claim 1, wherein said first transition region (b) includes a first pair of dimples (i) extending inwardly from an operative top surface of said first transition region (b).
6. The vehicle hood as claimed in claim 1, wherein said second transition region (d) includes a second pair of dimples (ii) extending inwardly from an operative top surface of said second transition region (d).
7. The vehicle hood as claimed in claim 1, wherein said collapsible bracket (204) is made of SPCC material.
8. The vehicle hood as claimed in claim 1, wherein said first flange (c) is welded on a horizontal and curved surface of said hood inner and said second flange (e) is welded on a flat vertical wall of said hood inner (205'), wherein said sub-profiles of said first flange (c) and said second flange (e) are complimentary to a profile of said hood inner.
9. The vehicle hood as claimed in claim 1, wherein said central region (a) of said collapsible bracket (204) is glued to said hood outer (205''), wherein a sealant is applied in said two grooves.
10. The vehicle hood as claimed in claim 9, wherein said sealant is applied in said two grooves such that a gap is formed between said central region (a) of the collapsible bracket (204) and said inner surface of the hood outer (205'').