FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION
Improved Stabiliser Bar of Twist Beam Structure For Rear Suspension And Method of Mounting Thereof
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
Balamurugan Janarthanam and Samir K Ghodekar
Both Indian Nationals
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
The present invention is related to suspension system of vehicles and more particularly this invention is related to improved stabiliser bar of twist beam structure for rear suspension and method of mounting thereof.
BACKGROUND OF INVENTION
Generally to increase the strength and the stiffness of the rear suspension twist beam structure, it is conventional to incorporate a tubular element called stabiliser bar in the structure. This hollow tubular bar is welded at the ends of the trailing arm.
Cold drawn Electric resistance Welded (CEW)/ Electric Resistance Welded (ERW) tubes are subjected to an operation to increase the thickness locally and to increase the strength thereof; a metallic cover is either press fitted or welded at the ends to prevent foreign particle entry in that region and subsequently corrosion is prevented.
When the section of the tubular bar is to be increased considerably for achieving higher roll stiffness of the suspension, the stresses at the joint location of the stabilizer bar increases considerably. So in order to reduce the stress at the joinery of stabilizer bar, alternate solutions are required.
OBJECT OF INVENTIONS
The main object of the present invention is to provide the improved stabiliser bar of twist beam structure for rear suspension.


Another object of the present invention is to provide the method of mounting of improved stabiliser bar of twist beam structure for rear suspension.
Another object of the present invention is to provide the improved stabiliser bar of twist beam structure for rear suspension, which increases the strength of the rear suspension structure.
Another object of the present invention is to provide the improved stabiliser bar of twist beam structure for rear suspension, which reduces the stress at the joinery of the stabiliser bar in the twist beam structure.
Still another object of the present invention is provide improved stabiliser bar of twist beam structure for rear suspension, which provides the sealing means to prevent the entry of foreign particles.
STATEMENT OF INVENTION
Improved stabiliser bar of twist beam structure for rear suspension comprises;
Hollow tubular member connected to the twist beam structure,
Trailing arm structure at both the ends connects the said hollow tubular
member by joinery means.
Pin member having circular cross-section configured to be disposed at both
ends of the said hollow tubular member.
Improved stabiliser bar of twist beam structure for rear suspension in accordance with this invention, wherein said pin member is press fitted at both ends of the said hollow tubular member.
Improved stabiliser bar of twist beam structure for rear suspension in accordance with this invention, wherein said joinery means is used to join said


trailing arm structure and said hollow tubular member is conventional joinery means.
Method of mounting improved stabiliser bar of twist beam structure for rear suspension comprises;
Selecting hollow tubular member for connecting to the twist beam structure, Disposing the pin member at both ends of the said hollow tubular member, Joining the said hollow tubular member to the said trailing arm structure
BRIEF DESCRIPTION OF INVENTION
In accordance with the novel embodiment of the present invention, improved stabiliser bar of twist beam structure for rear suspension of vehicles comprises hollow tubular member (1) having suitable diameter connected to the twist beam structure, trailing arm structure (2) having hollow structure, pin member (3) having circular cross section configured to be fitted in to the said hollow tubular member (1) to minimize the stresses in the joinery means formed between the said trailing arm structure (2) and said hollow tubular member. Said pin member (3) is press fitted to both ends of the hollow tubular member (1) for providing a structure similar to the homogeneous structure.
This arrangement, apart from reducing the stresses in the joinery means formed between the said trailing arms structure (2) and said hollow tubular member, pin member acts as a sealing means for preventing entry of foreign particles unlike other structures.
BRIEF DESCRIPTION OF DRAWINGS
Figure - 1 shows the pin member fitted to the ends of the hollow tubular member.


Figure—2 shows an isometric view of the twist beam welded structure. Figure - 3 shows the complete assembly twist beam welded structure of rear suspension.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings 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,
Now referring to figure-1, in accordance with the first embodiment of the present invention, the improved stabiliser bar of twist beam structure for rear suspension of vehicles comprises; hollow tubular member (1) having suitable diameter which is connected to the twist beam structure of vehicles, trailing arm (2) having hollow structure, pin member (3) having circular cross section configured to be fitted in to the said hollow tubular member (1). Trailing arm (2) which is joined to the said hollow tubular member (1) by joining means such as weld, nut and bolt, or any other joining means.
Said pin member (3) is press fitted to both end of the said hollow tubular member (1) to provide a structure similar to the homogeneous structure to the said hollow tubular member (1) which enables to reduce the stress in the joining means used to connect the said trailing arm (2) and said tubular member (1).
Pin member (3) having circular cross section which is configured to be fitted in to the said hollow tubular member (1) acts as the sealing member or sealing means to prevent the entry of foreign particles or dust inside the said hollow tubular member (1) unlike the other structures.


Now referring to figure 2, in accordance of the present invention, which shows the isometric view of the assembly of twist beam structure comprises; hollow tubular member which is inside of the cross beam (not shown in figure), trailing arm structure (2) and the pin member (3) with other components like spring seat, reinforcements, damper mounting brackets, wheel mounting bracket, pivot sleeve, etc.
Further referring to figure 3, in accordance with the present invention, which shows complete assembly of twist beam welded structure comprises; hollow tubular member (1) inside the cross beam (5),trailing arm structure (2) , pin member (3) with other components like spring seat (6), reinforcements(7), damper mounting brackets(4), pivot sleeve (.8) , wheel mounting bracket(9), etc.
Method of mounting of improved stabiliser bar of twist beam type rear suspension of vehicles, in accordance with this invention comprises; Selecting hollow tubular member (1) for connecting to the twist beam structure, Disposing the pin member (3) to both ends of the said hollow tubular member (1), joining the said hollow tubular member to said trailing arm (2) structure.
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 in so far as they come within the scope of the invention as claimed or the equivalents thereof.


WE CLAIM
1. Improved stabiliser bar of twist beam structure for rear suspension
comprises;
Hollow tubular member connected to the twist beam structure,
Trailing arm structure at both the ends connects the said hollow tubular
member by joinery means.
Pin member having circular cross-section configured to be disposed to
the said hollow tubular member.
2. Improved stabiliser bar of twist beam structure for rear suspension as claimed in claim 1 wherein said pin member is press fitted at both ends of the said hollow tubular member.
3. Improved stabiliser bar of twist beam structure for rear suspension as claimed in claim 1, wherein said joinery means is used to join said trailing arm structure and said hollow tubular member is conventional joinery means.
4. Method of mounting of improved stabiliser bar of twist beam structure for rear suspension comprises;
Selecting hollow tubular member for connecting to the twist beam
structure,
Disposing the pin member at both ends of the said hollow tubular
member,
Joining the said hollow tubular member to the said trailing arm
structure.
5. Vehicle comprising improved stabiliser bar of twist beam structure for
rear suspension as claimed in any of the preceding claims.


6. Improved stabiliser bar of twist beam structure for rear suspension and
method of mounting improved stabiliser bar of twist beam structure for rear suspension as herein described with reference to accompanying drawings.
Dated this 27th day of November 2007.



Abstract
Improved stabilizer bar of twist beam structure for rear suspension and method of mounting thereof
The present invention is related to improved rear suspension twist beam structure mounting and method of mounting thereof.
In accordance with the present invention, improved rear suspension twist beam structure mounting comprise; hollow tubular member for connecting to the twist beam structure, trailing arm having hollow structure, pin member having circular cross section to be fitted at both ends of the said hollow tubular member to provide a structure similar to the homogeneous structure. Said pin member is press fitted to the hollow tubular member.