FORM 2
THE PATENTS ACT 1970
(39 of 1970)
AND
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION (See Section 10; rule 13)
TITLE OF THE INVENTION Improved lower bodystructure for a vehicle
APPLICANTS
TATA MOTORS LIMITED, an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
INVENTORS
Mahendrakumar M S, Anilkumar C, Rajendra G.Patil
and Ravindra G. Rajhans all Indian national
of TATA MOTORS LIMITED an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.


FIELD OF INVENTION
This invention relates to bodystructure of a vehicle and more particularly relates to lower part of bodystructure.
BACKGROUND OF INVENTION
In case of a vehicle, bodystructure is very important to provide the required rigidity and robustness. Vehicle bodystructure is a combination of structural members viz. vertical members such as A pillar, B pillar, C pillar etc, cross members at floor and at roof, and longitudinal members. Floor, roof, firewall are the other membranes which connect these members to form the enclosure of a bodystructure. Arrays of long members and cross members, provided at floor level, are used primarily for supporting forces generated by the seat, seat belt anchorages during crash collisions. One of the most significant structural members is the long member which supports the body structure across its length. These long members are known as door sills and floor long members. Cross members are provided to connect these longitudinal members to obtain robustness to the structure. Partial long members up to firewall membrane are provided on the floor to support the seat mountings.
OBJECTS OF INVENTION
The main object of this invention is to provide lower bodystructure for vehicle having adequate strength to react the forces generated during collisions.
Yet another object of this invention is to provide lower bodystructure for vehicle which is having minimal structural members.

Another object of this invention is to provide lower bodystructure for vehicle which is simple in construction and cost effective.
STATEMENT OF INVENTION
Lower bodystructure for a vehicle comprising of sill long members, floor long members, at least one central long member and plurality of cross members, wherein said members are connected to each other to provide rigidity to the lower bodystructure, said central long member is provided in between said floor long members.
BRIEF DESCRIPTION OF INVENTION
Lower bodystructure of a vehicle in accordance with this invention basically
comprises of sill long members, floor long members and cross members. Said
members are connected to each other to provide rigidity to the lower
bodystructure. At least one central long member is provided in between said floor
long members to provide sufficient rigidity to the lower bodystructure and support
various components of vehicle such as seats, seat belts, parking brake etc.
Said central long member is made in one piece or made in plurality of pieces to
constitute as a central long member.
Said floor long members and central long member/s are provided to cover the
entire length of the vehicle to provide the required strength to the vehicle when the
vehicle front and/or rear end collide with other objects.
BRIEF DESCRIPTION OF DRAWING
Fig 1 shows the vehicle lower bodystructure in accordance with this invention.

DETAILED DESCRIPTION OF INVENTION
Referring now to the drawing wherein the showings are for the purpose of
illustrating a preferred embodiment of the invention only, and not for the purpose
of limiting the same
Referring to Fig 1, floor long members (1) are connected to each other through
plurality of cross members (2). Sill members (4) are connected to said floor long
members through plurality of gussets (5). At least one central long member (3) is
provided between the said floor long members and is connected to said cross
members. Said floor long members (1) and central long member/s (3) are provided
to cover the entire length of the vehicle to provide the required strength to the
vehicle when the vehicle front and/or rear end collide with other objects.
Said central long member (3) provides sufficient rigidity to the lower
bodystructure and supports various components of vehicle such as seat, seat belt,
parking brake etc.
Said central long member (3) is made in one piece or made in plurality of pieces to
constitute as a central long member.
Said central long member (3) can be oriented symmetrically or asymmetrically to
the floor long members (1) depending on the vehicle construction and packaging.
Said central long member (3) is provided across the entire length of the vehicle.
However as per requirement it can be provided only at select locations in the
vehicle structure at passenger compartment or engine compartment or combination
of them.
Said central long member (3) can also be provided with crumple zone in order
control the vehicle crash pulse in the event of crash.
Floor long members (1) and central long member (3) provide the required support
when the vehicle front and/or rear end collide with other objects.
Said sill long members (4) can be connected to the extended cross members (2) if
the provision of gussets is not feasible.

The accompanying figure describes vehicle lower bodystructure typical of a monocoque vehicle. However central long member can also be provided on a chassis frame of a body-over-chassis vehicle to improve the chassis frame structural performance.
The advantages associated with said body structure in the event of crash are -
a) This requires less structural material on lower structure of the bodyshell to react to the forces generated.
b) This body structure results in less intrusion in the passenger compartment.
The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.

WE CLAIM
1. Lower bodystructure for a vehicle comprising of sill long members, floor long members, at least one central long member and plurality of cross members, wherein said members are connected to each other to provide rigidity to the lower bodystructure, said central long member is provided in between said floor long members.
2. Lower bodystructure for a vehicle as claimed in claim 1 wherein said sill long members and floor long members are connected through plurality of gussets.
3. Lower bodystructure for a vehicle as claimed in claim 1 wherein said sill long members are connected to extended cross members.
4. Lower bodystructure for a vehicle as claimed in claim 1 to 3 wherein said central long member is provided symmetrically or asymmetrically to said floor long members.
5. Lower bodystructure for a vehicle as claimed in claims 1 to 4 wherein said central long member and /or floor long members are made in one piece or plurality of pieces.
6. Lower bodystructure for a vehicle as claimed in claims 1 to 5 wherein said central long member is provided across the entire length of the vehicle.

7. Lower bodystructure for a vehicle as claimed in claims 1 to 5 wherein said central long member is provided in selective zone/s along the length of vehicle.
8. Lower bodystructure for a vehicle as claimed in claims 1 to 7 wherein said central long member is provided with crumple zone.
9. Vehicle having monocoque or body over chassis construction with lower bodystructure as claimed in claims 1 to 8.
10. Lower bodystructure for a vehicle substantially as herein described with reference to accompanying drawing.
Dated this 29th day of March 2007