DESC:FORM 2

THE PATENTS ACT, 1970 (as amended)
[39 OF 1970]
&
The Patents Rules, 2003

COMPLETE SPECIFICATION
[See Section 10 and rule 13]

TITLE: “A REAR UNDERRUN PROTECTION SYSTEM FOR A VEHICLE AND A METHOD OF ASSEMBLING THEREOF”

NAME AND ADDRESS OF THE APPLICANT:

TATA MOTORS LIMITED, an Indian company, having its registered office at Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001 Maharashtra, India.

Nationality: Indian.

The following specification particularly describes the invention and the manner in which it is to be performed.
TECHNICAL FIELD
The present disclosure generally relates to a crash protection system for a vehicle. Particularly but not exclusively, embodiments of the disclosure disclose an improved rear underrun protection system for the vehicle.

BACKGROUND OF THE DISCLOSURE
Vehicles such as, but not limiting to, heavy vehicles including, but not limiting to, trucks, trailers and lorries, are generally designed with relatively high ground clearance. One of the reasons for this high ground clearance is for facilitating ambient driving conditions in a rough terrain. The exemplary range of clearance for in all the ends of such vehicle is about 100 to about 120 cm above the ground. Generally, in such vehicles there will be a serious risk with respect to road traffic safety. The reason for this is that during a possible collision between a truck and a passenger vehicle or small vehicles such as, but not limiting to, compact vehicles and commercial vehicles, there is a risk that the small vehicle will penetrate into the truck and thus be jammed between the road surface and the underside of the frame or load carrier of the vehicle. The result may be that the rear end of the truck will enter the passenger compartment of the smaller vehicle with great force, which in turn may cause serious injuries to the passengers of the smaller vehicle. To prevent such situations generally an underrun protection system is provided in the locations such as, but not limiting to, rear end, sides and front end of the heavy vehicle.

In one such situation, during a rear end collision event, “A” pillar of the small vehicle (as shown in figure 2) is exposed to collide with rear end of the heavy vehicle. The “A” pillar of the small vehicle or any automobile is not designed to withstand or absorb impact. Upon impact of the small vehicle to rear end of the heavy vehicle, the “A” pillar of the small vehicle immediately breaks without absorbing any of the impact forces and the passengers in the cabin of the small vehicle are directly exposed to the impacting surface. Thus, posing a serious threat to the passengers in the small vehicle and may lead to fatal injuries. Also, another possibility of impact of the small vehicle with the rear end of the heavy vehicle is the intrusion of small vehicle below the rear end of the heavy vehicle. Upon intrusion, the small vehicle will be jammed between the ground surface and the underside of the frame of the truck. This intrusion of the small vehicle below the rear end of the truck again has high risks for causing critical to fatal injuries to the passengers of the small vehicle as the passenger compartment is directly exposed to interact with the chassis frame portion of the heavy vehicle / truck. To avoid instances, such as impact on “A” pillar of the small vehicle, intrusion of the small vehicle and to increase safety of the passengers in the small vehicles during the collision, rear underrun protection systems are provided to the heavy vehicles.

Conventionally, the rear underrun protection system comprises a chassis frame longitudinal member in the form of a beam or channel (as shown in figure 1) installed at the rear end of the chassis frame of a heavy vehicle / truck. This rear under protection system, would be placed at predetermined distance above the ground surface, and the height is configured such that the system does not hinder the driving conditions of the heavy vehicle / truck. Further, the underrun protection systems are adapted such that when the small vehicle collides at substantially middle portion of the rear end of the heavy vehicle, the underrun protection system prevents the small vehicle from entering into the rear end of the heavy vehicle by stopping the front end of the small vehicle. However, upon a rear end collision at the overhanging ends of the rear underrun protection system, the overhanging end deforms/bends due to the impact of the small vehicle. Hence, allows penetration of the small vehicle into the rear end structure of the heavy vehicle (6), leading to A pillar interactions (as shown in figure 3a and figure 3b, with the point of contact of the transverse member indicated by a circle) and leading to fatal to maximum injuries to the passengers. [Also, another mechanism of the rear underrun protection system is configured with an adjustable mechanism to adjust the height of the rear underrun protection system, upon collision. The mechanism is configured such that upon collision, the height of the rear underrun protection system is reduced, so that the front structure of the small vehicle has structural engagement and hence prevents rear underrun. However, such mechanism is complicated due to requirement of many parts, and at the same time increases the cost of the underrun protection system. Even with such a system the rear under run protection system would bend during offset underride accident & the associated human risk continues].

In the light of the foregoing discussion, there is a need for an improved rear underrun protection system to overcome the limitations stated in the background.

SUMMARY OF THE DISCLOSURE
The shortcomings of the prior art are overcome and additional advantages are provided through the provision of the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the disclosure.

In one non-limiting embodiment of the present disclosure, there is provided a rear underrun protection system for a vehicle. The system comprises a first transverse member positioned at a predetermined distance below chassis frame longitudinal members of the vehicle, wherein the first transverse member is connectable to the chassis frame longitudinal members through a plurality of brackets. The system also comprises a second transverse member, connectable to rear ends of the chassis frame longitudinal members, which extends in either sides of the vehicle from centre of the vehicle, wherein, in an event of collision of a colliding small vehicle onto rear end of the vehicle, the first transverse member is configured to contact a bumper portion of the colliding small vehicle, and the second transverse member is configured to contact a bonnet portion of the colliding small vehicle, to refrain intrusion of the colliding vehicle, thereby preventing underrun into rear end of the vehicle.

In one embodiment of the present disclosure, the first transverse member is connectable to the second transverse member by a plurality of connecting members.

In one embodiment of the present disclosure, the system comprises at least one reinforcing element at the connecting junction between the second transverse member and each of the chassis frame longitudinal members.

In one embodiment of the present disclosure, the first transverse member and the second transverse member extend from one side to other side of the vehicle.

In one embodiment of the present disclosure, the system comprises a plurality of gusset member for supporting ends of the second transverse member, wherein one end of each of the plurality of gusset members are connected to the chassis frame longitudinal member, and the other end of each of the plurality of gusset members is connected to at least one end of the second transverse member. Further, each of the plurality of gusset members are provisioned at a predetermined angle with respect to chassis frame longitudinal axis of the vehicle.

In one embodiment of the present disclosure, one end of each of the plurality of connecting members is connected to the first transverse member and the other end is connected to the second transverse member. Further, the connecting members are provisioned perpendicular to the axis of the first transverse member and second transverse member.

In one embodiment of the present disclosure, a method for assembling a rear underrun protection system to a vehicle is disclosed. The method comprises acts of positioning a first transverse member at a predetermined distance below chassis frame longitudinal members of the vehicle, wherein the first transverse member is connectable to the chassis frame longitudinal members by a plurality of brackets. . The method further comprises act of connecting a second transverse member to rear ends of the chassis frame longitudinal members in transverse direction of the vehicle, wherein the second transverse member extends in either sides of the vehicle from centre of the vehicle, wherein in an event of collision of a colliding vehicle onto rear end of the vehicle, the first transverse member is configured to contact a bumper portion of the colliding vehicle, and the second transverse member is configured to contact a bonnet portion of the colliding vehicle, thereby refraining intrusion of the colliding vehicle, to prevent rear underrun into the vehicle.

In one embodiment of the present disclosure, the method comprises act of connecting each of the plurality of gusset members at ends of the second transverse member, wherein one end of each of the gusset member is connected to the each of the chassis frame longitudinal members and the other end is connected to each of the ends of the second transverse member.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BREIF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The novel features and characteristic of the disclosure are set forth in the appended description. The embodiments of the disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of the illustrative embodiment when read in conjunction with the accompanying drawings. One or more embodiments are now described, by way of example only, with reference to the accompanying drawings

Figure 1 illustrates perspective view of the conventional rear underrun protection system for the vehicle.

Figure 2 illustrates perspective view of the pillar arrangement in exemplary conventional automobile or colliding vehicle.

Figure 3a and 3b illustrates collision of colliding vehicle with the conventional rear underrun protection system of Figure 1.

Figure 4 illustrates wedging effect of a colliding vehicle onto rear end of a vehicle.

Figure 5 illustrates perspective view of rear underrun protection system in accordance with an embodiment of the present disclosure.

Figure 6 illustrates interaction of the rear end of the vehicle with the colliding vehicle due to the rear underrun protection system of Figure 5, in accordance with an embodiment of the present disclosure.

Figure 7 illustrates collision of colliding vehicle with the rear underrun protection system of Figure 5 in accordance with an embodiment of the present disclosure.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the assembly illustrated herein may be employed without departing from the principles of the disclosure described herein.

DESCRIPTION OF THE DISCLOSURE
The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the 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 disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosure, 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. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.

To overcome the limitations stated in the background, the present disclosure provides an improved rear underrun protection system for the vehicle. The system broadly comprises a first transverse member and a second transverse member. The first transverse member is provisioned at a predetermined distance below longitudinal members or chassis frame of a vehicle such as but not limiting to trucks or heavy vehicles. The first transverse member is configured to contact the bonnet portion of the colliding vehicle such as but not limiting to passenger vehicles or other small vehicles in the event of a collision. Also, the first transverse member is connected to the rear end of the chassis frame longitudinal members by a plurality of brackets. Further, the second transverse member is connected to the chassis frame longitudinal members of the vehicle in transverse direction and extends on either side from centre of the vehicle. In one embodiment of the present disclosure, the first transverse member extends to entire width of the vehicle. Also, the second transverse member is configured to contact the bonnet portion of the colliding vehicle in the event of a collision. In another embodiment of the present disclosure the first transverse member and second transverse member are connectable by plurality of connecting members. The plurality of connecting members are connected such that one end of each of the plurality of connecting members is connected to the second transverse member and the other end of each of the plurality of connecting members is connected to the first transverse member. The plurality of connecting members support the second transverse member to prevent intrusion of the small vehicle into the rear end of the vehicle, upon collision with the rear end of the heavy vehicle. Further, a plurality of gusset members are provisioned in between the chassis frame longitudinal members of the heavy vehicle and the second transverse member for providing additional support at the ends of the second transverse member.

In the event of collision of a colliding vehicle onto rear end of the heavy vehicle, the first transverse member contacts the bumper portion of the colliding vehicle. Due to the impact forces the first transverse member bends and thereby the front end of the colliding vehicle tries to intrude into the rear end of the vehicle. At this stage, the second transverse member contacts the bonnet portion of the colliding vehicle, typically much before the “A” pillar and locks the front end of the colliding vehicle. This is described as “wedging” or “wedge-locking”. Upon wedging of the colliding vehicle [as shown in Figure 4], the colliding vehicle stops immediately. Locking the front end of the colliding vehicle prevents further intrusion of the colliding vehicle into rear end of the vehicle and prevents the collision of ‘A’ pillar of the colliding vehicle with the rear end of the heavy vehicle. By avoiding the “A” pillar impact, fatal to maximum injuries to the passengers are prevented and thereby increase the safety of the passengers.

Henceforth, the present disclosure is explained with the help of one or more exemplary embodiments in conjunction with the drawings. However, such exemplary embodiments should not be construed as limitations of the present disclosure. A person skilled in the art can envisage various such embodiments without deviating from scope of the present disclosure.

Figure 5 is an exemplary embodiment of the present disclosure which illustrates perspective view of the rear underrun protection system (100). The rear underrun protection system (100) is provided to prevent the intrusion of a colliding vehicle (6) [shown in Figure 3a and 3b] into rear end of a heavy vehicle (1) in the event of collision. In one embodiment of the present disclosure, the colliding vehicle (6) referred herein above and below are small vehicles such as but not limiting to passenger vehicles, small pick-up trucks. In another embodiment of the present disclosure, the vehicle (1) is such as but not limiting to heavy vehicle including but not limiting to trucks, lorries and trailers.

The rear underrun protection system (100) of the present disclosure comprises a first transverse member (3) and a second transverse member (4), with the first transverse member (4) positioned at a predetermined distance below the chassis frame longitudinal members (2) of the vehicle (1) . The first transverse member (3) is connected to the chassis frame longitudinal members (2) of the vehicle (1) by a plurality of brackets (8), such that one end of the plurality of brackets (8) is connected to the chassis frame longitudinal members (2) and the other end of the plurality of brackets (8) is connected to the first transverse member (3). The plurality of brackets (8) supports the first transverse member (3) in the event of a collision. In one embodiment of the present disclosure, the plurality of brackets (8) are provided at substantially central portion of the first transverse member (3). Also, the first transverse member (3) is configured to contact a bumper portion (6b) [as shown in figure 6] of a colliding vehicle (6), in the event of collision of the colliding vehicle (6) with the rear end of the vehicle (1). Further, the second transverse member (4) is connectable to the chassis frame longitudinal members (2) and is configured such that the second transverse member (4) extends on either side from the centre of the vehicle (1). In one embodiment of the present disclosure, the second transverse member (4) extends to entire width of the vehicle (1). In another embodiment of the present disclosure, the second transverse member (4) extends from the centre of the vehicle (1) such that, overhanging ends (4a) are formed on either sides from centre of the vehicle (1). Also, the second transverse member (4) is configured to contact the bonnet portion (6a) [as shown in Figure 6] of a colliding vehicle (6), in the event of collision of the colliding vehicle (6) with the rear end of the vehicle (1). Further, the first transverse member (3) is connected to the second transverse member (4) by a plurality of connecting members (5), such that end (5a) of each of the plurality of connecting member (5) is connected to the first transverse member (3) and the other end (5b) of each of the plurality of connecting member (5) is connected to the second transverse member (4). The incorporation of the plurality of connecting members (5) along with plurality of brackets (8), provides additional strength to the first transverse member (3) in the event of an impact. Due to this system, the second transverse member (4) prevents intrusion of the colliding vehicle (6) in an event of collision. In one embodiment of the present disclosure, the first transverse member (3) is configured in the same length as that of the second transverse member (4).

Further, the cross-sections of the first transverse member (3) and second transverse member (4) are selected such that it is capable of withstanding the impact of the colliding vehicle (6). In an exemplary embodiment of the disclosure, the preferred cross section of the first and second transverse members (3 and 4) is an open section such as “C” shaped member. In another embodiment of the present disclosure, the first transverse member (3) and second transverse member (4) is a closed section member such as but not limiting to round section, square section etc. In one embodiment of the present disclosure, the cross-section of the first transverse member (3) and second transverse member (4) is selected from group such as but not limiting to C-section, square or any other cross-section which suffice the need to withstand the impact of the colliding vehicle (6). In one embodiment of the present disclosure, the plurality of connecting members (5) are provisioned perpendicular to the longitudinal plane of the vehicle (1). In another embodiment of the present disclosure, the cross-section of plurality of connecting members (5) is selected from group such as but not limiting to rectangular, C-section etc. Further, the first transverse member (3) is connected onto each of the chassis frame longitudinal members (2) by plurality of brackets (8), using fasteners such as nut and bolt. In an embodiment of the disclosure, the components of the rear under protection system (100) such as first transverse member (3), second transverse member (4), plurality of connecting member (5), the plurality of gusset members (7) and plurality of brackets (8)are fixedly connected to each other using a suitable mechanism such as welding, and brazing . In alternative embodiment of the disclosure, the components of the rear under protection system (100) such as first transverse member (3), second transverse member (4), plurality of connecting member (5), the plurality of gusset members (7) and plurality of brackets (8) are removably connected to each other using a suitable members such as fasteners. In one embodiment of the present disclosure, at least one reinforcing element (4b) is configured in between the connecting junctions of the second transverse member (4) and the chassis frame longitudinal members (2).

The rear under protection system (100) further comprises a plurality of gusset members (7) connected in between the second transverse member (4) and the chassis frame longitudinal members (2) of the vehicle (1). In an embodiment of the disclosure, the gusset members (7) are provided on either ends of the second transverse member (4), such that one end of each of the plurality of the gusset members (7) is connected to the chassis frame longitudinal member (2) and the other end is connected to the ends of the second transverse member (4), for supporting the ends (4a). The plurality of gusset members (7) support the ends (4a) by reducing bending of the ends (4a) upon collision, in other words, the plurality of gusset members (7) are configured to withstand the bending moment forces experienced by the second transverse member (4). The plurality of gusset members (7) are provisioned such that, they are inclined at a predetermined angle with respect to the longitudinal axis of the vehicle (1). For example, if the plurality of gusset members (7) are connected at extreme ends (4a), then the bending moment the second transverse member (4) can withstand, will be higher. Hence, the plurality of gusset members (7) prevents intrusion of the colliding vehicle (6) in the event of collision at the end portions of the first transverse member (3).

In the event of a collision of the colliding vehicle (6), at the centre portion of the rear under run protection system (100), the first transverse member (3) initially contacts the bumper portion (6b) of the colliding vehicle (6). The first transverse member (3) therefore absorbs maximum amount of impact force of the colliding vehicle (6). The plurality of connecting members (5) provides required support to the first transverse member (3) to withstand the impact of the colliding vehicle (6).

In the event of intrusion of colliding vehicle (6) at the ends of the rear underrun protection system, the end portions of the first transverse member (3) contacts the bumper portion (6a) of the colliding vehicle (6). The first transverse member (3) withstands the impact of the colliding vehicle (6),. During the process, the first transverse member (3) bends [as shown in figure 6], thereby the colliding vehicle (6) tries to further intrude into the rear end of the vehicle (1). At this stage, the second transverse member (4) contacts the bonnet portion (6b) of the colliding vehicle (6) [shown in figure 6 and figure 7]. Now, the second transverse member (4) with the support from the plurality of gusset members (7), locks the colliding vehicle (6) by forcing the colliding vehicle (6) to the ground. Thereby prevents further intrusion of the colliding vehicle (6) into the rear end of the vehicle (1).

Hence in the event of collision, only the front end of the colliding vehicle (6) is crumpled due to impact either at the centre or at the ends of the second transverse member (4), with the passenger cabin remaining safe.

In an embodiment of the disclosure, the rear underun protection system is fixedly connected to the vehicle using a suitable mechanism such as welding, and brazing. In alternative embodiment of the disclosure, the rear underun protection system is removably connected to the vehicle using a suitable members such as fasteners.

Advantages:
In one embodiment, the present disclosure provides an improved rear underrun protection system which prevents under ride of the small vehicle particularly, but not limited, in case of collision at the ends of the rear end of the heavy vehicle.

In one embodiment of the present disclosure an improved rear underrun protection system is provide which is simple in construction, easy to assemble and retrofit-table.

Equivalents
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Table of Referral Numerals
Referral Numerals Description
100 Rear underrun protection system
1 Vehicle
2 Chassis frame longitudinal members
3 First transverse member
4 Second transverse member
4a Ends of second transverse member
4b Reinforcement members
5 Connecting member
5a and 5b Ends of the connecting member
6 Colliding vehicle
6a Bumper portion of colliding vehicle
6b Bonnet portion of colliding vehicle
7 Gusset member
8 Plurality of brackets

,CLAIMS:We claim:
1. A rear underrun protection system (100) for a vehicle (1), the system (100) comprising:
a first transverse member (3) positioned at a predetermined distance below chassis frame longitudinal members (2) of the vehicle (1), wherein the first transverse member (3) is connectable to the chassis frame longitudinal members (2) through a plurality of brackets (8); and
a second transverse member (4) connectable to rear ends of the chassis frame longitudinal members (2) in transverse direction of the vehicle (1), wherein the second transverse member (4) extends in either sides of the vehicle (1) from centre of the vehicle (1);
wherein, in an event of collision of a colliding vehicle (6) onto rear end of the vehicle (1), the first transverse member (3) is configured to contact a bumper portion (6b) of the colliding vehicle (6), and the second transverse member (4) is configured to contact a bonnet portion (6a) of the colliding vehicle (6), to refrain intrusion of the colliding vehicle (6), thereby preventing underrun into rear end of the vehicle (1).

2. The system (100) as claimed in claim 1, wherein the first transverse member (3) is connectable to the second transverse member (4) through a plurality of connecting members (5).

3. The system (100) as claimed in claim 1 comprises at least one reinforcing element (4b) at the connecting junction between the second transverse member (4) and each of the chassis frame longitudinal members (2).

4. The system (100) as claimed in claim 1, wherein the first transverse member (3) and the second transverse member (4) extend from one side to other side of the vehicle (1).

5. The system (100) as claimed in claim 1 comprises a plurality of gusset member (7) for supporting ends (4a) of the second transverse member (4).

6. The system as claimed in claim 5, wherein one end of each of the plurality of gusset members (7) are connected to the chassis frame longitudinal members (2), and the other end of each of the plurality of gusset members (7) is connected to at least one end of the second transverse member (4).

7. The system (100) as claimed in claim 5, wherein each of the plurality of gusset members (7) are provisioned at a predetermined angle with respect to chassis frame longitudinal axis of the vehicle (1).

8. The system (100) as claimed in claim 1, wherein one end of each of the plurality of connecting members (5) is connected to the first transverse member (3) and the other end is connected to the second transverse member (4).

9. The system (100) as claimed in claim 1, wherein the connecting members (5) and the plurality of brackets (8) are provisioned perpendicular to the axis of the first transverse member (3) and second transverse member (4).

10. A method for assembling a rear underrun protection system (100) to a vehicle (1), the method comprises acts of:
positioning a first transverse member (3) at a predetermined distance below a chassis frame longitudinal members (2) of the vehicle (1), wherein the first transverse member (3) is connectable to the chassis frame longitudinal members (2) by a plurality of brackets (8); and
connecting a second transverse member (4) to rear ends of the chassis frame longitudinal members (2) in transverse direction of the vehicle (1), wherein the second transverse member (4) extends in either sides of the vehicle (1) from centre of the vehicle (1);
wherein, in an event of collision of a colliding vehicle (6) onto rear end of the vehicle (1), the first transverse member (3) is configured to contact a bumper portion (6b) of the colliding vehicle (6), and the second transverse member (4) is configured to contact a bonnet portion (6a) of the colliding vehicle (6), thereby refraining intrusion of the colliding vehicle (6), to prevent rear underrun into the vehicle (1).

11. The method as claimed in claim 10 comprises act of connecting a gusset member (7) at ends (4a) of the second transverse member (4).

12. The method as claimed in claim 10, wherein one end of each of the gusset member (7) is connected to the chassis frame longitudinal members (2) and the other end is connected to each of the overhanging ends (4a) of each of the second transverse member (4).

13. A vehicle comprising a rear underrun protection system (100) as claimed in claim 1.

Dated this 5th day of February, 2015 GOPINATH A.S.
OF K&S PARTNERS
IN/PA 1852
AGENT FOR THE APPLICANT