FORM 2
THE PATENT ACT 1970
[39 OF 1970]
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
[See Section 10 and Rule 13]
“AN ADAPTABLE ENEGRY ABSORBING STRUCTURES FOR FRONT END OF
VEHICLE AND THE METHOD THEREOF”
Name and Address of the Applicant: TATA MOTORS LIMITED, Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai – 400001, Maharashtra, India.
Nationality: Indian
The following specification particularly describes the nature of the invention and the manner in which it is to be performed.

TECHNICAL FIELD
The present invention relates to chassis long member of a vehicle, particularly relates to front/rear end crash longitudinal members or long members provided in the vehicle chassis for absorbing the crash impact energy.
BACKGROUND OF THE DISCLOSURE
The long members or the chassis members form an important structure which supports the complete vehicle. The chassis or the long members is analogous to an animal skeleton over which all the other parts of the vehicle are mounted like vehicle body frame, engine, transmission etc. The chassis or a long member of the vehicle is the most crucial part of the entire vehicle which provides stability and rigidness for the vehicle. In the event of a crash or accident, these members act as energy absorbers which dissipate the kinetic energy of the vehicle and ensure safety to the vehicle occupants seated inside the vehicle.
The long members have been provided with crush initiators in the front or in the rear end of the long members. The main aim of the crush initiators is to initiate deformation and absorb the impact energy by crushing which will reduce the decelerations that would be generated on the rest of the vehicle structure. The long member ends are designed for a predetermined energy absorption. The crush initiators have a progressive crush pattern for a controlled collapse of the structure. The vehicle front/rear end structures are provided with crush initiators for taking up frontal impacts as well as impacts from the rear end of the vehicle.
As a part of a platform strategy during vehicle development, variants of vehicles are built around the same long members. However, the energy absorption factor of the long member would vary depending on the vehicle mass and the target speed or impact speed.
An existing front/rear end vehicle chassis long member is illustrated in Figure 2. Figure shows primary long member (1’) of the chassis of a vehicle having plurality of crush initiators (2’) on the surface of the primary long member (1’). A Secondary long member (3’) having plurality of crush initiators (2’) with an engaging plate (5’) fixed at one end and the other end of the secondary long member (3’) has a support plate (4’) fixed to it and is in turn fixed to one end of the primary long member (1’). The support plate (4’) differentiates primary long member (1’) from the secondary long member (3’) by acting as a barrier between the two long members. The engaging plate (5’) provided at the front end of the secondary long member (3’) acts as a first contact member during the time of an impact. The

plurality of crush initiators (2’) provided on the surface of the primary long member (1’) and secondary long member (3’) helps in progressive crush behaviour. The secondary long member (3’) is designed to absorb impact energy in the event of slow speed impact and the said primary long member is designed for absorbing impact energy at high speeds. However, during the event of a high impact crash, the primary long member (1’) has no reinforcements provided and hence leads to additional deformation on the primary long member which causes serious damage to the vehicle chassis. Hence there exists a requirement to resist the impact forces generated during the event of a crash and to prevent serious damages to the vehicle chassis.
Modifications to an already established long member design for higher energy absorption is generally quite expensive for various reasons. The press tools used in the manufacturing of the long members need to be changed in design and the press tools are quite expensive and it is a tedious process. The manufacturing facility would require maintaining variety of press tools leading to higher locked up inventory costs and higher budget for the manufacturing company to bear. Increase in product timeline due to change in vehicle styling and packaging with the increase in length of front/rear end structural members according manufacturing changes have to be made accordingly.
OBJECTS OF THE DISCLOSURE
The objective of the present invention is to provide an improved long member at the front/rear end of a vehicle which increases the impact energy absorption capacity easily with a controlled collapse of the structure by maintaining the progressive crush behaviour.
Another objective of the present invention is to provide an improved long member at the front/rear end of a vehicle which is simple in construction and cost effective to increase the effective absorption of the impact energy during the event of a crash of the vehicle.
SUMMARY OF THE DISCLOSURE
The shortcomings of the prior art are overcome and additional advantages are provided through the provision as claimed in 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 claimed disclosure.

In an embodiment of the disclosure the vehicle chassis long member of a vehicle is described. At least one primary long member fixed to either ends of the chassis having plurality of crush initiators on surface of the primary long members and at least one secondary long member having plurality of crush initiators on surface of secondary long member is connected to the Primary long member. Wherein, at least one support plate is provided in between the secondary long member and the primary long member, and first engaging plate is fixed to the free end of the secondary long member. At least one tertiary long member having plurality of crush initiators on surface of tertiary long member, with a second engaging plate fixed to one end of the tertiary long member placed within the primary long member at a predetermined distance from the support plate, and the other end of the tertiary long member is fixed to the inner walls of the primary long member.
In an embodiment of the disclosure the chassis long member of a vehicle is described, wherein the second engaging plate of the tertiary long member is connected to the support plate by means of a connecting link placed in between the tertiary long member and the support plate.
In an embodiment of the disclosure the chassis long member of a vehicle is described, wherein the support plate is provided with a cut out.
In an embodiment of the disclosure, the chassis long member of a vehicle is described, wherein the first engaging plate of the secondary long member is connected to the second engaging plate of the tertiary long member connected by means of a connecting link and one end of the connecting link passes through the cut out provided on the support plate.
In an embodiment of the disclosure, the chassis long member of a vehicle is described, wherein the first engaging plate of the secondary long member is fixed with a connecting link and the other end of the connecting link protrudes out through the cut out provided on the support plate and is fixed to the third engaging plate.
In an embodiment of the disclosure, the chassis long member of a vehicle is described, wherein the third engaging plate fixed to one end of the connecting link is placed at a predetermined distance from the second engaging plate of the tertiary long member.
In an embodiment of the disclosure, the chassis long member of a vehicle is described, wherein a cover plate is fixed over the primary long member forming an enclosure.

In an embodiment of the disclosure, the chassis long member of a vehicle is described, wherein shape of the primary long members, secondary long member and tertiary long member is selected from a group comprising rectangular-shape hollow tubes, square-shape hollow tubes and cylindrical shape tubes.
In an embodiment of the disclosure, the chassis long member of a vehicle is described, wherein plurality of crush initiators are selected from a group comprising ridge shape initiators, V-groove shape initiators, U-shape initiators and trapezoidal shape initiators.
In an embodiment of the disclosure, a method of providing impact absorbers in a vehicle chassis is described, said method comprising acts of providing primary long member having plurality of crush initiators on surface of the primary long member at either ends of vehicle chassis; connecting atleast one secondary long member having plurality of crush initiators on surface of the secondary long member to the primary long member wherein, at least one support plate is provided in between primary and secondary long members and first engaging plate is connected to the free end of the secondary long member and placing a tertiary long member having plurality of crush initiators on surface of the tertiary long member within the primary long member wherein, one end of the tertiary long member is fixed to inner walls of the primary long member and the free end of the tertiary long member is connected to a second engaging plate.
In an embodiment of the disclosure, a method of providing impact absorbers in a vehicle chassis is described, wherein a connecting link is provided in between the second engaging plate and support plate to transfer the impact energy from the support plate to the tertiary long member.
In an embodiment of the disclosure, a method of providing impact absorbers in a vehicle chassis is described, wherein a connecting link is provided in between first engagement plate and second engagement plate by passing the connecting link through a cut out provided in the support plate to transfer the impact energy from the first engagement plate to the tertiary long member.
In an embodiment of the disclosure, a method of providing impact absorbers in a vehicle chassis is described, wherein a third engagement plate is provided within the primary long member at a predetermined distance from the second engagement plate and providing a

connecting link between third engagement plate and first engagement plate such that the connecting link passes through the cut out provided on the support plate.
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.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The novel features and characteristic of the disclosure are set forth in the appended claims. 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 an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:
Figure 1 shows side view of a vehicle with partial cut out showing the location of the front end of the vehicle highlighted.
Figure 2 shows isometric view of existing front/rear end of the chassis long member (prior art).
Figure 3 shows the exploded view of the front/rear end of a vehicle chassis long member in accordance with the invention.
Figure 4 shows isometric transparent view of front/rear end of a chassis long member in accordance with the invention.
Figure 5 shows the dynamic crushing of the front/rear end of a chassis long member used in state of the art vehicle.
Figure 6 shows the dynamic crushing of the front/rear end of a chassis long member in accordance with the invention.
Figure 7 to 9 shows various alternate arrangements of the front/rear end of a chassis long member in accordance with the invention.

Figure 10 shows graphical representation of Energy absorption vs time for the proposed and conventional long member.
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 structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION OF 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. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.
Referring now to the drawings wherein the drawings are for the purpose of illustrating a exemplary embodiment of the disclosure only, and not for the purpose of limiting the same.
Figure 1 is an exemplary embodiment of the disclosure and illustrates a partial cut out of the front end of the vehicle showing the location of the chassis long member highlighted at the front end of the vehicle.

Figure 3 shows an exploded view of the said vehicle chassis long member in accordance with the invention. Exploded view shows various parts included in the assembly of a vehicle chassis long member. The primary long member (1) has an opening at the top as shown having plurality of crush initiators (2) on its surface and acts as a primary impact energy absorber in the event of a high impact crash. The assembly further includes a secondary long member (3) having plurality of crush initiators (2) with an engaging plate (5) fixed to one end of the secondary long member (3) and a support plate (4) fixed to the other end of the primary long member (3). The engaging plate (5) provided on the secondary long member (3) is the first to come in contact to during an impact and equally distributes the impact energy across its surface area. The support plate (4) acts as a barrier between the primary long member (1) and secondary long member (3). The assembly also includes a tertiary long member (7) having plurality of crush initiators (2) provided on the surface which acts as an additional reinforcement member to the primary long member for increasing the resistive force of the entire chassis long member. A connecting link (6) and a cover plate () are included in the assembly, wherein the connecting link (6) is used to connect the tertiary long member (7) and the secondary long member (3) for transmission of impact energy forces from secondary long member (3) to tertiary long member (7) in the event of a high speed crash. The cover plate (8) is provided to cover the primary long member (1) forming an enclosure.
Figure 4 shows a transparent isometric view of a front/rear end of a vehicle chassis long member in accordance with the invention. The front/rear end of a vehicle chassis includes a tertiary long member (7) which is placed within the primary long member (1). One end of the tertiary long member (7) is fixed to the inner walls of the primary long member (1) by suitable fasteners (9). The other end of the tertiary long member (7) has an engaging plate (5) fixed to it. Plurality of crush initiators (2) is provided on the surface of tertiary long member (7) for progressive crush behaviour during a crash. The stiffness of the tertiary long member (7) can be varied accordingly to achieve progressive crush behaviour for controlled collapse. Variation in stiffness of the long members can be achieved by varying the distance between each crush initiator. For example, when the distance between the crush initiators is more, stiffness reduces in contrary to this stiffness increases with the reduction in the distance between the crush initiators. In general, stiffness of a chassis is inversely proportional to the distance between the crush initiators. The tertiary long member (7) and the support plate (4) are connected by a connecting link (6) provided in between the tertiary long member (7) and support plate (4). Also a covering plate (8) is provided on the primary long member (1)

which forms an enclosure. During the event of a high speed crash the secondary long member
(3) crushes and transfers the rest of the impact force to the connecting link (6) connected in between the support plate (4) and engaging plate (5) of the tertiary long member (7). The connecting link (6) provided in between the tertiary long member (7) and the support plate
(4) acts as an impact energy distributer.
Figures 5 & 6 show the dynamic crush modes of the prior art long member & the improved long members respectively. In the prior art, a primary long member (1) having plurality of crush initiators (2) is fixed to the secondary long member (3) having plurality of crush initiators (2) on its surface. A support plate (4) divides the two primary long member (1) and secondary long member (3). During the event of a low speed crash, progressive crush occurs only to the secondary long member (3) and stops at the support plate (4). The primary long member (1) comes into the picture only when a high speed crash occurs. The secondary long member (3) after getting progressively crushed transfers rest of the impact energy to the primary long member (1). The impact energy is absorbed by the crush initiators (2) provided on the primary long member (1) and deformation of the primary long member (1) initializes as shown in the Figure 5.
In the vehicle chassis long member as developed in the present invention as shown in figure 6 includes an additional tertiary long member (7) which is placed within the primary long member (1) fixed to the inner walls of the primary long member (1). A connecting link (6) placed in between the support plate (4) and the tertiary long member (7) helps transfer the impact energy forces evenly onto the tertiary long member (7) and helps in a progressive crush. Also, the resistive force offered by the improved chassis long member is much higher than it is described in the prior art and the energy absorption is also high.
Figure 7 illustrates a possible variation of the instant invention. A tertiary long member (7) is placed within the primary long member (1) and one end of the tertiary long member (7) is fixed to the inner walls (10) of the primary long member (1) using suitable fasteners (9). In the present variation there is an absence of a connecting link (6). The tertiary long member (7) is placed at a predetermined distance from the support plate (4). The distance between the support plate (4) and the engaging plate of the tertiary member is less which enables early participation of the tertiary long member (7) during a high speed impact. During the event of a high speed crash the secondary long member (3) crushes progressively and again progressive crush occurs to the tertiary long member (7). This kind of arrangement offers

impact force resistance at the starting of the long member and deformation of the long member occurs in the starting only.
Figure 8 shows another possible variation in which, the support plate (4) has a cut out (11). One end of a connecting link (6) passes through the cut out (11) of the support plate (4) and is fixed to an engaging plate (5). There is an increased gap between the engaging plate (5) of the connecting link (6) and the engaging plate (5) of the tertiary long member (7). This gap helps in the late participation of the tertiary long member (7) in the case of a high speed crash. It also manages the time of engagement in the event of a crash and also helps in positioning the tertiary and the connecting link within the primary long member.
Figure 9 shows another possible variation of the chassis long member in which, one end of the connecting link (6) is fixed to the engaging plate (5) of the secondary long member (3) and the other end passes through the cut out (11) provided on the support plate (4) and fixed to the engaging plate of the tertiary long member (7). This helps in simultaneous involvement of the tertiary long member (7) during the event of a high speed crash.
Figure 10 shows graphical representations showing the difference in energy absorption levels between conventional and proposed long members. The energy absorption level of the conventional long member is comparatively less when compared with the energy absorption level of the proposed long member.
REFERENCE NUMERALS

1’ Primary Long Member (prior art)
2’ Crush Initiators
3’ Secondary Long Member
4’ Support Plate
5’ Engaging Plate
1 Primary Long Member
2 Crush Initiators

3 Secondary Long Member
4 Support Plate
5a First Engaging Plate
5b Second Engaging Plate
5c Third Engaging Plate
6 Connecting Link
7 Tertiary Long Member
8 Cover Plate
9 Fasteners
10 Inner Walls
11 Cut Out
A Vehicle
B Chassis long member
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

limiting, with the true scope and spirit being indicated by the following claims. embodiments disclosed herein are for purposes of illustration and are not intended to be

WE CLAIM:
1. The chassis of a vehicle comprising:
at least one primary long member (1) fixed to either ends of the chassis having plurality of crush initiators (2) on surface of the primary long members (1);
at least one secondary long member (3) having plurality of crush initiators (2) on surface of secondary long member (3) is connected to the Primary long member (1); wherein, at least one support plate (4) is provided in between the secondary long member (3) and the primary long member (1), and first engaging plate (5a) is fixed to the free end of the secondary long member (3);
at least one tertiary long member (7) having plurality of crush initiators (2) on surface of tertiary long member (7), with a second engaging plate (5b) fixed to one end of the tertiary long member (7) placed within the primary long member (1) at a predetermined distance from the support plate (4), and the other end of the tertiary long member (7) is fixed to the inner walls (10) of the primary long member (1) using fasteners (9).
2. The chassis of a vehicle as claimed in claim 1, wherein the second engaging plate (5) of the tertiary long member is connected to the support plate (4) by means of a connecting link (6) placed in between the tertiary long member (7) and the support plate (4).
3. The chassis of a vehicle as claimed in claim 1, wherein the support plate (4) has a cut out (11).
4. The chassis of a vehicle as claimed in claim 1, wherein the first engaging plate (5a) of the secondary long member (3) is connected to the second engaging plate (5b) of the tertiary long member (7) by means of a connecting link (6) and one end of the connecting link (6) passes through the cut out (11) provided on the support plate (4).
5. The chassis of a vehicle as claimed in claim 1, wherein the first engaging plate (5a) of the secondary long member (3) is fixed with a connecting link (6) and the other end of the connecting link (6) protrudes out through the cut out (11) provided on the support plate (4) and is fixed to the third engaging plate (5c)

6. The chassis of a vehicle as claimed in claim 1, wherein the third engaging plate (5c) fixed to one end of the connecting link (6) is placed at a predetermined distance from the second engaging plate (5b) of the tertiary long member (7).
7. The chassis as claimed in claim 1, wherein a cover plate (8) is fixed over the primary long member (1) forming an enclosure.
8. The chassis of a vehicle as claimed in claim 1, wherein shape of the primary long members (1), secondary long member (3) and tertiary long member (7) is selected from a group comprising rectangular-shape hollow tubes, square-shape hollow tubes and cylindrical shape tubes.
9. The chassis of a vehicle as claimed in claim 1, wherein plurality of crush initiators (2) are selected from a group comprising ridge shape initiators, V-groove shape initiators, U-shape initiators and trapezoidal shape initiators.
10. A method of providing impact absorbers in a vehicle chassis, said method comprising acts of:
providing primary long member (1) having plurality of crush initiators (2) on surface of the primary long member (1) at either ends of vehicle chassis;
connecting atleast one secondary long member (3) having plurality of crush initiators (2) on surface of the secondary long member (3) to the primary long member (1); wherein, at least one support plate (4) is provided in between primary and secondary long members (3) and first engaging plate (5a) is connected to the free end of the secondary long member (3); and
placing a tertiary long member (7) having plurality of crush initiators (2) on surface of the tertiary long member (7) within the primary long member (1); wherein, one end of the tertiary long member (7) is fixed to inner walls of the primary long member (1) and the free end of the tertiary long member (7) is connected to a second engaging plate (5b).
11. The method as claimed in claim 10, wherein providing a connecting link (6) between the
second engaging plate (5b) and support plate (4) to transfer the impact energy from the
support plate (4) to the tertiary long member (7).

12. The method as claimed in claim 10, wherein providing a connecting link between first engagement plate (5a) and second engagement plate (5b) by passing the connecting link through a cut out (11) provided in the support plate (4) to transfer the impact energy from the first engagement plate (4) to the tertiary long member (7).
13. The method as claimed in claim 10, providing a third engagement plate (5c) within the primary long member (1) at a predetermined distance from the second engagement plate (5b) and providing a connecting link (6) between third engagement plate (5c) and first engagement plate (5a) such that the connecting link (6) passes through the cut out (11) provided on the support plate (4).