DESC:FIELD OF THE INVENTION

The present invention relates to car body improvement. In particular, the present invention relates to improvements in body-in-white (BIW) cross-member for cars. More particularly, the present invention relates to integrated energy absorber incorporated in the BIW for meeting the structural as well pedestrian lower leg requirements according to ECE statutory criteria.

BACKGROUND OF THE INVENTION

Body-in-white (BIW) is meant by that stage in car manufacturing, in which the sheet metal components of the car body are welded together. This is also the stage before various parts involving movements (doors, hoods, and deck lids as well as bumpers), motor, chassis sub-assemblies, or trim (glass, seats, upholstery, electronics, etc.) and the like have been assembled, particularly before painting them.

Almost two-thirds of 1.2 million people worldwide killed every year in road traffic crashes are the pedestrians. Despite the serious magnitude of this existing problem, most attempts at reducing the pedestrian deaths have focused solely on education and traffic regulation. Crash engineers have begun to use design principles that have proved successful in protecting the car occupants to develop vehicle the design concepts that reduce the likelihood of injuries to pedestrians in the event of car-pedestrian crashes. These design efforts involve redesigning car’s bumper, hood (bonnet), windshield and pillar in order to be energy absorbing (having softer impact) without compromising the structural integrity of the car. Further, most pedestrian crashes involve a forward moving car (as opposed to buses and other vehicles with a vertical hood/bonnet). In such a crash, a standing or walking pedestrian is struck and accelerated to the speed of the car and then continues forward as the car brakes to a halt. So, the pedestrian is impacted twice, first by the car and then by the ground. But, most fatal injuries occur due to the pedestrian’s interaction with the car.

The vehicle designers usually focus their attention on understanding the car-pedestrian interaction, which is characterized by the following sequence of events (see Figures 1a and 1b): the vehicle bumper first contacts the lower limbs of the pedestrian, the leading edge of the hood hits the upper thigh or pelvis, and the head and upper torso are struck by the top surface of the hood and/or windshield. Most limb injuries occur due to a direct blow from the bumper and the leading edge of the hood. This leads to contact fractures of the femur and the tibia/fibula and damage to the knee ligaments due to bending of the joint.

Thus, the attempts at reducing these injuries involve reducing the peak contact forces by making the bumper softer and increasing the contact area and also by limiting the amount of knee bending by modifying the geometry of the front end of the car. Various computer simulations and experiments with cadavers demonstrate that when cars have lower bumpers, the thigh and leg rotate together causing the knee to bend less and thus reducing the likelihood of ligament injuries. Deeper bumper profiles and structures under the bumper (such as the air dam) can also assist in limiting the rotation of the leg.

Shuler, S., Mooijman, F., and Nanda, A. "Bumper Systems Designed for Both Pedestrian Protection and FMVSS Requirements: Part Design and Testing", SAE Technical Paper 2004-01-1610, 2004, doi:10.4271/2004-01-1610 [in the article entitled: “Bumper Systems Designed for Both Pedestrian Protection and FMVSS Requirements: Part Design and Testing”] have observed in the abstract that in order to meet current FMVSS (Federal Motor Vehicle Safety Standard) and ECE42 legislation and European Enhanced Vehicle Safety Committee (EEVC) requirements for lower leg pedestrian impact protection, extensive research work was initiated in a number of automotive working areas.

A dual performance car bumper system, i.e. a 4 km/hr barrier and pendulum combined with lower leg impact protection is achieved through a combination of material properties and design. The difficulty in designing such a system arises from the conflicting bumper system requirements.

In order to achieve the lower leg protection, a relatively soft bumper system is required, while a relatively stiff system is typically needed to manage the barrier and pendulum impacts. Using computational analysis modelling, an injection molded energy absorber (EA) was designed and built to demonstrate the ability to achieve pedestrian protection requirements for knee bending angle, knee shear displacement, and tibia acceleration as well as 4 km/hr pendulum and barrier impacts (ECE42, FMVSS). The energy absorber was also tested to assess 8 km/hr pendulum and barrier impact performance (CMVSS - Canadian Motor Vehicle Safety Standard). The results have shown that an injection molded EA using polycarbonate/polybutylene terephthalate (PC/PBT) resin could meet both the FMVSS and the pedestrian safety requirements and could do so within a packaging space representative of the vehicle styling (typically 80 to 120 mm). However, this Energy Absorber is an additional part that needs to be attached to the car body with additional mountings / connections, which results in excess weight, cost and assembly time. Hence, a unique design has been considered for the BIW lower cross member as shown in the figure, which meets the structural requirement as well as the pedestrian lower leg requirement as per ECE-R78/AIS-100.

In the BIW, a bottom cross-member is used for providing the required Structural Stiffness and to connect the bumper mounting brackets. In order to meet the Pedestrian Lower Leg requirements, an Energy Absorber is conventionally used to meet the regulatory criteria of ECE-R78/AIS-100. This part (Figure 2b) was designed with a unique profile the necessary cross-sections for meeting the Stiffness requirements and with beads at specific locations for local weakening. It is attached to the car body by spot welds at the bottom of the headlamp panels and is also used for supporting the bumper and bumper mounting brackets.

PRIOR ART

Figures 2a and 2b show a baseline design of the BIW cross-member, which uses excess material and is also very complex to assemble. It was found by using Computer Aided Engineering (CAE) simulation processes that the baseline design does not meet the regulatory criteria for Pedestrian Lower Leg requirements and shows high acceleration and Knee Bending Angles at most of the points. For instance, the lower leg impact points at Y= 0 mm and Y = 400 mm, the acceleration values are 226.5 g and 350.2 g respectively, which are well above the acceptance limit of 170 g. Similarly, the Knee Bending Angles are typically 19.59 degrees and 23.75 degrees respectively for the above mentioned points, which are above the acceptance limit of 19 degrees.

DISADVANTAGES WITH THE PRIOR ART

There were several constraints noticed in the conventional automobile design, e.g. car design, wherein a front end beam runs across the vehicle for safety purposes. However, by taking into consideration of the pedestrian safety requirements, this main sub-assembly of the vehicle becomes a critical component, which also becomes the hard point in the car capable of causing pedestrian injuries.

Various studies were conducted to investigate the existing configurations of the integrated BIW cross-member and energy absorber assembly. The following conventional ways were found to reduce the pedestrian injury:

• Making the bumper softer
• Increasing the contact area
• Increasing space and
• Providing energy absorbers.

However, out of the above four, the first three cannot be changed, as they would obviously lead to greater engineering efforts and thus to incur huge additional costs.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide an optimized BIW bottom cross-member for cars.

Another object of the present invention is to provide a BIW cross-member, which meets the Structural Stiffness and Pedestrian Lower Leg requirements according to various regulatory criteria.

Still another object of the present invention is to provide an integrated energy absorber for a BIW cross-member, which is light-weight and is cost-effective.

A further object of the present invention is to provide a BIW cross-member which facilitates in reducing the accelerations to safely meet the regulatory requirements without compromising with the strength and bumper mounting connection thereof.

A still further object of the present invention is to provide a BIW cross-member which facilitates in reducing the Knee-Bending Angles without compromising with the strength and bumper mounting connection thereof.

Another object of the present invention is to provide an integrated BIW cross-member and energy absorber, which reduces material consumption.

Yet another object of the present invention is to provide an integrated BIW cross-member and energy absorber, which reduces the cost of manufacture.

Still further object of the present invention is to provide an integrated BIW cross-member and energy absorber, which reduces the assembly time.

Yet further object of the present invention is to provide an integrated BIW cross-member and energy absorber, which facilitates the ease of assembly.

A still further object of the present invention is to provide an integrated BIW cross-member and energy absorber assembly, which substantially promotes the pedestrian safety.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided an integrated energy absorber and body cross-member assembly for automobile BIW, wherein the integrated energy absorber and body cross-member assembly comprises:

(a) a plurality of local weakening provided at predetermined locations for meeting the structural requirements and the integrated energy absorber;

(b) a profiled shape with a plurality of profiles for maintaining the load flow path with respect to the crash loads as well as durability loads by utilizing significantly lesser material;

(c) a plurality of horizontal single beads of uniform depth configured for avoiding the crumping of the cross-structure and for facilitating the ease of formability and for providing structural stiffness;

wherein the integrated energy absorber and body cross-member assembly is attached to the BIW by means of a plurality of spot welds at the bottom of the head lights, i.e. close to the body mount, for providing a frontal crash protection.

Typically, each local weakening is configured as a depression in the cross-member structure for facilitating ease of assembly with other parts thereof.

Typically, the predetermined deformable crush space is configured in the cross-section of the integrated BIW body cross-member and energy absorber, the crush space extending both in horizontal and vertical directions to correspond to the position of the energy absorber.

Typically, the body cross-member is configured as the pedestrian lower leg energy absorber.

Typically, the assembly also supports the bumper and the brackets, whereby the acceleration is reduced at point Y = 0 mm to approximately 70 g to 80 g, preferably 75.8 g and the acceleration is reduced at point Y = 400 mm to approximately 95 to 105 g, preferably 99.8 g.

Typically, the knee bending angle is reduced at point Y= 0 mm to approximately 0.90 to 1.00 degree, preferably 0.96 degree and the knee bending angle is reduced at point Y= 400 mm to approximately 0.65 to 0.75 degree, preferably 0.69 degree.

Typically, the assembly comprises:

(i) a predetermined frontal cross-section for imparting the energy absorber adequate deformable crush space;

(ii) a crush space matching the position of the energy absorber;

(iii) a plurality of depressions configured for facilitating local weakening of the structure and for providing ease of assembly with other parts;

(iv) the shape is configured to maintain the load flow path with respect to crash as well as durability loads by using substantially lesser material and by considering the manufacturability constraints;

(v) a plurality of horizontal single beads of uniform depth for protection from crumping and for facilitating formability and for providing stiffness to the parts;

(vi) a uniform rear cross-section with smooth merger at the lateral ends; and
(vii) a predetermined shape for meeting the structural stiffness in Y direction and for facilitating ease of joinery by means of spot welds welded close to the body mount; and for providing frontal crash protection.

Typically, the acceleration Y is reduced at the point Y= 0 mm to approximately 70 g to 80 g, preferably 75.8 g and the acceleration is reduced at the point Y= 400 mm to approximately 95 to 105 g, preferably 99.8 g.

Typically, the knee bending angle is reduced at the point Y= 0 mm to approximately 0.90 to 1.00 degree, preferably 0.96 degree and the knee bending angle is reduced at the point Y= 400 mm to approximately 0.65 to 0.75 degree, preferably 0.69 degree.

Typically, the predetermined deformable crush space extends both in horizontal and vertical directions to correspond to the position of the energy absorber in the cross-section of the integrated BIW body cross-member and energy absorber; and wherein the body cross-member is configured as the pedestrian lower leg energy absorber.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described with reference to the accompanying drawings, wherein:

Figure 1a represents a car-pedestrian crash event (courtesy Wikipedia);

Figure 1b shows an event after the car-pedestrian crash of Figure 1a at a critical time (courtesy Wikipedia);

Figure 2a shows a perspective view of the conventional configuration of the front portion of an automobile, particularly illustrating the complex assembly of BIW bottom cross-member;

Figure 2b specifically shows the front view of the bottom cross-member of the conventional configuration of Fig. 2a, wherein use of excess material is quite evident;

Figure 3a shows a perspective view of an optimized integrated BIW body cross-member and energy absorber configured in accordance with the present invention, to be fitted at the front of the BIW body assembly;

Figure 3b specifically shows the front view of the integrated BIW body cross-member and energy absorber configured in accordance with the present invention, representing optimized configuration and offering ease of assembly;

Figure 4a shows a perspective view of the conventional BIW body configuration, illustrating the front end beam running across the vehicle for safety purposes;

Figure 4b shows a perspective view of the conventional energy absorber to be fitted on the front portion (bumper) of the vehicle, which gets deformed during a crash and thereby absorbs the impact and the energy thereof;

Figure 5a shows a front view of the conventional body-cross member assembly of a Toyota RAV4, one of the benchmark vehicles for the present invention;

Figure 5b shows a front view of the conventional body-cross member assembly of a Ford Kuga model 2008, another benchmark vehicle for the present invention;

Figure 5c shows a front view of the conventional body-cross member assembly of a Hyundai 2.7 model 2008, yet another benchmark vehicle for the present invention;

Figure 6 shows a perspective view of the structural configuration of the bumper of the vehicle, illustrating the integrated BIW body cross-member and energy absorber configured in accordance with the invention;

Figure 7a shows detailed isometric view of the integrated BIW body cross-member and energy absorber of the vehicle configured according to the invention;

Figure 7b shows detailed top view of the integrated BIW body cross-member and energy absorber of the vehicle configured according to the invention;

Figure 7c shows the front detailed view of the integrated BIW body cross-member and energy absorber of the vehicle configured according to the invention; and

Figure 7d shows an isometric view of the vehicle bumper incorporating the integrated BIW body cross-member and energy absorber configured in accordance with the invention.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The integrated BIW body cross-member and energy absorber in accordance with the present invention for a vehicle will now be described in more details with reference to the accompanying drawings, without limiting the scope and ambit of the present disclosure in any way.

Figure 1a shows an event of the car-pedestrian crash after a lapse of about 30 milliseconds which proves to be critical for the pedestrian leg injury. The vehicle bumper first contacts the lower limbs of the pedestrian; the leading edge of the hood hits the upper thigh or pelvis. A pedestrian P is hit by a car running on road G on the legs 2 by the bumper 4 and cross-member 6 of the car C. Within this small interval of 30 millisecond of the crash, the legs 2 are seen already bent to some degree.

Figure 1b shows another event after the event represented in Figure 1a, i.e. at the time of the impact of the pedestrian against the car bonnet / windshield, i.e. after a lapse of about 220 milliseconds, which also proves critical for the pedestrian injury. By this time, the head and upper torso of the pedestrian are hit against the top surface of the bonnet 8 and/or the windshield 10 of the vehicle C. Until now, the engineers have attempted to overcome this problem by using deformable mounts. The limb injuries occur due to a direct blow from the bumper and the leading edge of the hood. This leads to contact fractures of the femur and the tibia/fibula and damage to the knee ligaments due to bending of the joint. Further, various attempts have also been made for lowering the limb injuries by reducing the peak contact forces through making the bumper softer and increasing the contact area and also by limiting the amount of knee bending through modifying the geometry of the car’s front end.

Figure 2a shows the conventional baseline configuration of the front portion of an automobile, which particularly illustrates the complex assembly of BIW bottom cross-member, which is used for providing it the required structural stiffness and also facilitates it the connection to bumper mounting brackets.

Figure 2b specifically shows the front view of the bottom cross-member of the conventional baseline configuration shown in Fig. 2a, which clearly demonstrates use of excess material and requires longer time for the assembly to the BIW body, therefore resulting in a substantially higher material and assembly costs and which increases overall manufacturing costs. The conventional energy absorber is also shown, which is to be attached to satisfy the Pedestrian Lower Leg requirements according to the regulatory criteria under ECE-R78/AIS100 for safety reasons.

Figure 3a shows a preferred embodiment of the optimized configuration of the integrated cross-member and energy absorber in accordance with the present invention fitted at the front of the body assembly in the BIW. A unique profile was developed for this purpose, which has necessary cross-sections to meet the structural stiffness requirements. It also has beads at specific locations for allowing the local weakening.

Figure 3b specifically shows the front view of the integrated BIW body cross-member and energy absorber configured in accordance with the present invention. This represents an optimized configuration useful for ease of assembly. This integrated assembly is attached to the BIW body by means of a plurality of spot welds at the bottom of the head light panels. This assembly is also used for supporting the bumper and the brackets. This way, by integrating the BIW body cross-member and the lower leg energy absorber with the new configuration, the accelerations and knee bending angles could be easily controlled throughout the bumper width within the required regulatory limits. At points Y = 0 mm and Y = 400 mm, the acceleration was brought down to 75.8g and 99.8 g respectively. Similarly, the Knee Bending Angle was reduced to 0.96 degrees and 0.69 degrees respectively. Therefore, the reductions in accelerations and Knee Bending Angles are achieved by using this optimized configuration of the BIW body cross-member integrated with the energy absorber according to the present invention. This configuration successfully meets the regulatory criteria within the prescribed safety limits and that too without making any compromise with the BIW strength and bumper mounting connections. This novel configuration of the integrated cross-member and energy absorber in accordance with the present invention also reduces the overall material consumption, optimizes the cost of manufacturing, substantially reduces assembly time and facilitates ease of assembly of BIW. This concept has proven to be a cost effective and low weight design. It is a unique solution arrived at by combining the functionality of these two important parts of the BIW body. Therefore, this solution appropriately meets the Pedestrian Lower Leg performance according to prescribed regulatory criteria.

Figure 4a shows a perspective view of the conventional BIW body configuration, illustrating the front end beam running across the vehicle for safety purposes. This front cross-member is encircled and marked as 20. In the conventional automobile or car design, a front end beam runs across the vehicle for safety purposes. However, by taking into consideration of the pedestrian safety, this main sub-assembly of the vehicle becomes a critical component, which is also the hard point in the car capable of causing pedestrian injury. In order to investigate the existing configurations of the integrated BIW cross-member and energy absorber assembly, various studies were conducted. Accordingly, there are following conventional ways to reduce the pedestrian injury:

• To make the bumper softer
• To increase the contact area
• To increase space and
• To provide energy absorbers.

However, out of the above four, the first three cannot be changed, as they would obviously lead to greater engineering efforts and huge additional costs to implement. This also adds up to weigh more, increases the development (tuning) time, packaging and substantially raises the overall costs. In addition, in order to investigate the functioning of various configurations of the existing car BIW bodies, some of the conventional benchmark models of different manufacturers have been discussed in the following figures 5a, 5b and 5C.

Figure 4b shows the conventional energy absorber (bumper) assembly to be fitted on the front portion of the vehicle, e.g. 2003 and 2004 models of Marauder. This requires an energy bumper 22, which gets deformed during an accident and thereby absorbs the impact of the accident and the energy thereof. The assembly consists of an energy absorber 23 made of a soft material to be covered by a bumper cover 24, a reinforcement bar 26 carrying the energy absorber 23 and cover 24 on the BIW body (marked 20 in Figure 4a) by means of a plurality of bumper brackets 27 and their respective stud plates 28. Thus, further reconfiguring the bumper, bonnet, and windshield to make these more energy absorbing (softer) without compromising the structural integrity of the car is the still the need of the hour.

Figure 5a shows a front view of the body-cross member assembly of a Toyota RAV4, one of the benchmark vehicles for the present invention. In this model, the BIW body cross-member is present at a lower position and slightly rearwards, thereby it acts as a hard point for pedestrian in a frontal accident. This adversely affects the pedestrian leg, when the leg/s impact the BIW body structure, thereby resulting in a high knee bending and knee shear with more knee acceleration.

Figure 5b shows a front view of the body-cross member assembly of a Ford Kuga model 2008, another benchmark vehicle for the present invention. In this model, the BIW body cross-member is substantially flat and laid back, thereby this also acts as a hard point for the pedestrian. Since the cross-member is flat and has no deformable space, it adversely affects, when pedestrian leg/s impact/s the BIW body structure, thereby this also results in a high knee bending and knee shear with more knee acceleration.

Figure 5c shows a front view of the body-cross member assembly of a Hyundai 2.7 model 2008, yet another benchmark vehicle for the present invention. An extra cross-member is added in this model, which absorbs the impact energy. However, none of the above discussed prior-arts bench-marked models are not cost-effective.

Therefore, by keeping in mind the requirements of strength, safety and overall manufacturing costs of the BIW body structure of the applicants, the present inventors have configured the new structure, such that:

1. A minimal amount of extra material/parts/joineries is used.

2. The cross section helps to deform the structure thus reducing the knee deceleration and knee displacement.

3. Optimal position of the structure makes the bending angle under control.

4. Optimal use of material by not adding any extra foam, rubber or metal to absorb energy.

5. Tuned properly to meet the requirements of durability, crash and manufacturability.

Figure 6 shows a perspective view of the structural configuration of the bumper 40 of the vehicle, illustrating the integrated BIW body cross-member and energy absorber in accordance with the invention, which is made of steel. It requires no additional parts, as described in Figure 5c above. Moreover, the cross-member and energy absorber are made of an integrated configuration, thereby number of parts is reduced, making the assembly easier, thereby needing reduced development time and resulting in reduced overall costs of the BIW body structure.

One of the embodiments of the present invention is discussed below with reference to Figures 7a to 7c. This embodiment of the integrated cross-member and energy absorber has the following advantages:

1. Weight of the structure is reduced, since no new part is added.
2. Overall cost is also reduced, because no new part is added.
3. Development time of the part is reduced, as no new part is added.
4. No additional brackets or fitments for joining the energy absorber.
5. Statutory Pedestrian Lower Leg criteria are met successfully.
6. Durability criteria are also suitably met.
7. All the surrounding packing remains the same, thus no packing issues are envisaged.
8. Ease of assembly of the integrated cross-member and energy absorber on the BIW body structure, thus requiring less no. of parts.
9. Cross-member is made of steel and no separate materials, e.g. foam, rubber etc. are needed to be used, so development time and the overall cost of investment is required to be increased.

Figure 7a shows an isometric detailed view of the integrated BIW body cross-member and energy absorber of the vehicle configured in accordance with the invention. The energy absorber is provided with an adequate deformable crush space 41 in the cross Section 42 (Figure 7b) thereof. This crush space 41 is provided, both in horizontal (here) and vertical (Figure 7c) directions, to match with the position of the energy absorber. Further, depressions 43 are configured for local weakening of the cross-member structure in order to provide the ease of assembly with other parts thereof. The profiled shape 44 is configured for maintaining the load flow path w.r.t both the crash loads and durability loads, which utilizes much lesser material. Another profile 45 maintains the load flow path w.r.t both crash and durability loads by taking into account of the constraints of manufacture thereof. The horizontal single bead 46 of uniform depth is provided for avoiding the crumping of the cross-structure and for facilitating the ease of formability and to provide it structural stiffness. The uniform cross section 47 is provided with smooth merging at the side ends.

Figure 7b shows the detailed top view of the integrated BIW body cross-member and energy absorber of the vehicle configured in accordance with the invention. The energy absorber is configured with an adequate deformable crush space 41 in the cross Section 42 thereof. This crush space 41 is shown here in the vertical direction to match with the position of the energy absorber.

Figure 7c shows the front detailed view of the integrated BIW body cross-member and energy absorber of the vehicle in accordance with the invention. The depressions 43 are also shown here, which are provided for local weakening of the structure along with the ease of assembly with other parts. The shape 48 is configured, so as to meet the structural stiffness in Y direction by maintaining the ease of joining, i.e. requires only spot welds and no additional brackets. Since these joints are close to the body mount, they do not affect the strength of the overall cross-member structure. The configurations shown in Figures 7a, 7b and 7c facilitate a frontal crash protection, which refers to the structural function that it would perform by absorbing some energy and allow certain load path for the energy flow in case of the a frontal crash.

Figure 7d shows an isometric view of the structural configuration of the bumper 40 of the vehicle, incorporating the integrated BIW body cross-member and energy absorber made of steel and configured in accordance with the invention. The portions marked in single/double headed red arrows indicate the major components/features of the inventive features thereof, including a deformable crush space 41 in the cross section 42 (Figure 7b) thereof and provided both in horizontal (here) and vertical (Figure 7c) directions, local weakening or depressions 43, profiles 44, 45, horizontal single beads 46and uniform cross section 47.

WORKING PRINCIPLE OF THE INVENTION

In the case of an impact by the lower leg of a pedestrian, the lower limb parts (hereinafter referred as Lower Leg Impactor or simply Impactor) impacts against the front of the vehicle at a particular velocity. During the impact, the parts at the front of the vehicle start to deform by absorbing the energy from this impactor. The vehicle bumper being the front most part of the vehicle, it absorbs certain energy and transfers the remaining to the inner parts of the vehicle. If there are not any energy absorbing parts, the impactor would directly interact with the inner parts of the vehicle, thereby giving a higher injury values (measured in terms of the tibia deceleration, knee shear displacement and knee bending angle). So, there is a need for the energy absorbing parts in order to reduce these injury values. The device in accordance with the present invention, i.e. the energy absorbing means is so configured and positioned in front of the vehicle that during the impact by this impactor, the device in accordance with the invention gets deformed and the impact energy is appropriately absorbed, thus reducing the above-mentioned injury values. As the impactor may hit anywhere in the front of the vehicle, the details of the device in accordance with the invention, such as shape, cross sections etc. mentioned in Figures 7a,7b & 7c are so configured that they absorb the maximum impact energy, and thereby help in reducing these injury values.

TECHNICAL ADVANTAGES & ECONOMIC SIGNIFICANCE

Some of the technical advantages of the integrated BIW body cross-member and energy absorber proposed in accordance with the present invention are as under:

1. Reduction in Weight as no new part is being added.
2. Reduction in Cost as no new part is being added.
3. Reduction in Development time of the part as no new part is being added.
4. No addition of brackets or fitments for joinery of the energy absorber.
5. Pedestrian criteria met.
6. Durability criteria met.
7. All the surrounding packing is the same so no packing issues.
8. Ease of assembly. (less parts)
9. Made of steel, no separate material like foam, rubber, etc., used. So no development time & investment cost.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to implies including a described element, integer or method step, or group of elements, integers or method steps. However, it does not imply excluding any other element, integer or step, or group of elements, integers or method steps. In the claims and the description, the terms “containing” and “having” are used as linguistically neutral terminologies for the corresponding terms “comprising”.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention. Furthermore, the use of the term “one” shall not exclude the plurality of such features and components described.

The description provided herein is purely by way of example and illustration. The various features and advantageous details are explained with reference to this non-limiting embodiment in the above description in accordance with the present invention.

The descriptions of well-known components and manufacturing and processing techniques are consciously omitted in this specification, so as not to unnecessarily obscure the specification. In the previously detailed description, different features have been summarized for improving the conclusiveness of the representation in one or more examples.

However, it should be understood that the above description is merely illustrative, but not limiting under any circumstances. It helps in covering all alternatives, modifications and equivalents of the different features and exemplary embodiments.

Many other examples are directly and immediately clear to the skilled person because of his/her professional knowledge in view of the above description. Therefore, innumerable changes, variations, modifications, alterations may be made and/or integrations in terms of materials and method used may be devised to configure, manufacture and assemble various constituents, components, subassemblies and assemblies according to their size, shapes, orientations and interrelationships.

While considerable emphasis has been placed on the specific features of the preferred embodiment described here, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other changes in the preferred embodiment of the invention 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 invention and not as a limitation.

The exemplary embodiments were selected and described in order to be able to best represent the principles and their possible practical application underlying the invention. Thereby, the skilled persons can optimally modify and use the invention and its different exemplary embodiments with reference to the intended use. ,CLAIMS:We claim:

1. An integrated energy absorber and body cross-member assembly for automobile BIW, wherein the integrated energy absorber and body cross-member assembly comprises:

(a) a plurality of local weakening provided at predetermined locations for meeting the structural requirements and the integrated energy absorber;

(b) a profiled shape with a plurality of profiles for maintaining the load flow path with respect to the crash loads as well as durability loads by utilizing significantly lesser material;

(c) a plurality of horizontal single beads of uniform depth configured for avoiding the crumping of the cross-structure and for facilitating the ease of formability and for providing structural stiffness;

wherein the integrated energy absorber and body cross-member assembly is attached to the BIW by means of a plurality of spot welds at the bottom of the head lights, i.e. close to the body mount, for providing a frontal crash protection.

2. Integrated energy absorber and body cross-member assembly as claimed in claim 1, wherein each local weakening is configured as a depression in the cross-member structure for facilitating ease of assembly with other parts thereof.

3. Integrated energy absorber and body cross-member assembly as claimed in claims 1 to 2, wherein predetermined deformable crush space is configured in the cross-section of the integrated BIW body cross-member and energy absorber, the crush space extending both in horizontal and vertical directions to correspond to the position of the energy absorber.

4. Integrated energy absorber and body cross-member assembly as claimed in claims 1 to 3, wherein the body cross-member is configured as the pedestrian lower leg energy absorber.

5. Integrated energy absorber and body cross-member assembly as claimed in claims 1 to 4, wherein the assembly also supports the bumper and the brackets, whereby the acceleration is reduced at point Y = 0 mm to approximately 70 g to 80 g, preferably 75.8 g and the acceleration is reduced at point Y = 400 mm to approximately 95 to 105 g, preferably 99.8 g.

6. Integrated energy absorber and body cross-member assembly as claimed in claim 5, wherein the knee bending angle is reduced at point Y= 0 mm to approximately 0.90 to 1.00 degree, preferably 0.96 degree and the knee bending angle is reduced at point Y= 400 mm to approximately 0.65 to 0.75 degree, preferably 0.69 degree.

7. Integrated energy absorber and body cross-member assembly as claimed in claims 1 to 6, wherein the assembly comprises:

(i) a predetermined frontal cross-section for imparting the energy absorber adequate deformable crush space;

(ii) a crush space matching the position of the energy absorber;

(iii) a plurality of depressions configured for facilitating local weakening of the structure and for providing ease of assembly with other parts;

(iv) the shape is configured to maintain the load flow path with respect to crash as well as durability loads by using substantially lesser material and by considering the manufacturability constraints;

(v) a plurality of horizontal single beads of uniform depth for protection from crumping and for facilitating formability and for providing stiffness to the parts;

(vi) a uniform rear cross-section with smooth merger at the lateral ends; and

(vii) a predetermined shape for meeting the structural stiffness in Y direction and for facilitating ease of joinery by means of spot welds welded close to the body mount; and for providing frontal crash protection.

8. Integrated energy absorber and body cross-member assembly as claimed in claims 7, wherein the acceleration Y is reduced at the point Y= 0 mm to approximately 70 g to 80 g, preferably 75.8 g and the acceleration is reduced at the point Y= 400 mm to approximately 95 to 105 g, preferably 99.8 g.

9. Integrated energy absorber and body cross-member assembly as claimed in claim 8, wherein the knee bending angle is reduced at the point Y= 0 mm to approximately 0.90 to 1.00 degree, preferably 0.96 degree and the knee bending angle is reduced at the point Y= 400 mm to approximately 0.65 to 0.75 degree, preferably 0.69 degree.

10. Integrated energy absorber and body cross-member assembly as claimed in claims 7 to 9, wherein the predetermined deformable crush space extends both in horizontal and vertical directions to correspond to the position of the energy absorber in the cross-section of the integrated BIW body cross-member and energy absorber; and wherein the body cross-member is configured as the pedestrian lower leg energy absorber.

Dated this 27th day of January, SANJAY KESHARWANI
APPLICANT’S PATENT AGENT