FORM 2
THE PATENT ACT, 1970,
(39 OF 1970)

THE PATENTS RULE, 2003
COMPLETE SPECIFICATION
(SEE SECTION 10; RULE 13)

"THE SIDE SILL REINFORCEMENT STRUCTURE FOR AUTOMOTIVE
VEHICLES"

MAHINDRA & MAHINDRA LIMITED
AN INDIAN COMPANY,
R & D CENTER, AUTOMOTIVE SECTOR,
89, M.I.D.C., SATPUR,
NASHIK - 422 007,
MAHARASHTRA, INDIA.

THE FOLLOWING SPECIFICATION DESCRIBES THE NATURE OF THE
INVENTION AND MANNER IN WHICH IT IS TO BE PERFORMED

FIELD OF INVENTION:

The present invention is related to the structure of body of an automotive vehicle. More particularly the present invention is related to the side sill reinforcement structure of an automotive vehicle.

BACKGROUND OF THE PRESENT INVENTION:

Body Side is critical subsystem in BIW (body in white) from crashworthiness performance point of view as well as in durability point of view and comprises of Roof rail, Side Sill, A-Pillar, B-Pillar, C-pillar & Quarter and D-Pillar. It has important function of distributing impact loads for various parts of the vehicle without getting deformed as its deformation may cause higher injuries to occupant due to intrusions.
Among these members, the Side Sill in particular has multiple roles in both
frontal impact (Full frontal and Offset deformable Barrier (ODB) impact) and
side impact Moving deformable barrier (MDB) and Dynamic side pole)
scenarios. In frontal impact sill has to effectively transfer impact loads to rear portion of vehicle without getting deformed (Local front end deformations due to tire intrusions or global column buckling due to Euler's column buckling effect) In MDB side impact sill has to, transfer loads into side body throughout its length maintaining section stability. The dynamic side pole impact requires side sill to have high moment carrying capacity.

Conventionally to increase the section modulus in sill section many reinforcement members in sill section are provided or the thickness of the existing reinforcement members is increased. One of the conventional way is to have formed parts of steel to reinforce sill section. But this forming process is at severe limitation when it comes to using UHSS materials due to formability and capacity requirement issues.

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PRIOR ART

US 2009/0261622A1 document describes a side sill of a vehicle comprising an outer shell, an inner shell coupled to the outer shell, a space located between the' outer and the inner shell and adopted to receive a roll profile, wherein the inner and outer shells are, after being coupled to each other, adapted to receive a roll profile into the space after body frame work for the vehicle is substantially completed.
In this invention no reinforcement means are provided to with stand deformation in case of accidental frontal impact and side impact.

OBJECTIVES OF THE PRESENT INVENTION:

The main object of the present invention is to provide a novel and torsionally stiff side sill reinforcement structure for automotive vehicles.
Another object of the present invention is to provide side sill reinforcement structure having the bulkheads throughout the length of Sill Inner.
Another object of the present invention is to provide side sill reinforcement structure that improves the crashworthiness of the vehicle.

Another object of the present invention is to provide side sill reinforcement structure comprising bulk heads with circular holes placed along length of sill which ensure section stability.

Still further object of the present invention is to provide a side sill structure for automotive vehicle that imparts high ground clearance, low step-in-height and specific styling requirement.

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STATEMENT OF INVENTION

Accordingly the invention provides The side sill reinforcement structure for
automotive vehicles comprises a longitudinal sill member, fixed to the vehicle body
by a front bracket and rear bracket means, having inner side and outer side; a
number of flanges, in the form bulkheads all round it with notches and a hole in the
centre, with one end welded to the said sill member to the inner panel at distance
and parallel to each other welded along the longitudinal direction of the vehicle.

DESCRIPTION OF THE FIGURES:

Figure 1 shows the perspective view of side sill reinforcement structure in
accordance with the present invention.

Figure 2 shows the bulkheads of reinforcement structure.

Figure 3 shows another embodiment of the present invention with circular
pipe member

Figure 4 shows the sill box section from the front end with circular pipe
member.

DETAILED DESCRIPTION OF THE PRESENT INVENTION:

The present invention comprises of reinforcements secured to the right and
left side sills (1) of an automotive vehicle. Each of the reinforcements has
flanges (2) in the form of bulkheads all around it with notches (3) at each
corner and hole (4) at centre of the bulkhead (2). The entire reinforcement
structure is welded with side Sill inner panel along the longitudinal direction of
the vehicle.

In case of frontal impact while running the vehicle, an overload in the
longitudinal direction is applied to the front enj q@tUiANd2Oqi The rigidity of
the sill section disperses the excessive compressive load to the C-Pillar

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disposed at the rear of the vehicle body. The failure modes here could be
local front end deformations caused by tyre intrusions (particularly ODB
impact load case) and Euler's column buckling. In this invention, Bulkheads
reinforces the Sill Inner and contributes major part in avoiding the Buckling
and hence effectively transfers axial compressive loads to rear portion of
structure.

In MDB (Moving deformable barrier) side impact the sill has to transfer the loads to side body throughout the length. This is particularly true for vehicles in which sill is placed relatively higher from the ground generally. This means sill will come in to contact with MDB directly (Unlike in passenger cars). The Bulk heads ensures delayed section collapse of sill in MDB load case and hence ensures better performance. The position of the Bulkheads is finalized by doing iteration in the Crash Simulation.
In dynamic side pole impact, the bulk head positions along the length of Sill are optimized to suit dynamic pole locations.

In another embodiment of this invention, the circular pipe member is inserted through the holes of Bulkheads as shown in Figure 3. The pipe member is Arc welded with the bulkheads. The ends of the pipe are welded with End brackets. Finally the entire reinforcement structure is welded with side Sill inner panel along the longitudinal direction of the vehicle through End brackets and Bulkheads.

ADVANTAGES OF THE PRESENT INVENTION:
• The structure is considerably light in weight.
• The structure is easy to assemble and easy to replace.
• The structure requires less material and no mechanical or permanent
fasteners are required.
• The system does not produce the rattle noise.

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WE CLAIM:-

1. The side sill reinforcement structure for automotive vehicles comprises
a longitudinal sill member, fixed to the vehicle body by a front bracket
and rear bracket means, having inner side and outer side; a number of
flanges, in the form bulkheads all round it with notches and a hole in
the centre, with one end welded to the said sill member to the inner
panel at distance and parallel to each other welded along the
longitudinal direction of the vehicle.
2. The side sill reinforcement structure as claimed in claim 1 wherein
circular pipe member is inserted through the said holes of said bulk
head and fixed rigidly therein with arc welding.
3. The side sill reinforcement structure as claimed in claim 2 wherein the
ends of the said pipe member is welded with end brackets.
4. The side sill reinforcement structure as claimed in claims 1 to 3
wherein the positioning of the said bulkheads on the inner side of sill
member is finalized by doing iteration in the Crash Simulation.
5. The side sill reinforcement structure for automotive vehicles as claimed
in claims 1 to 4 above and as herein described with reference to the
figures of the accompanying specification.