FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION
"EGR PIPE" 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
INVENTORS Kannappachetty Veeramani, Makarand Shrikrishna Kulkarni,
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 describes the invention
1

Field of Invention:
The present invention relates to a sealing bush on EGR pipe. The present invention particularly relates to a sealing bush for mating exhaust pipes, one of the pipes being an EGR (exhaust gas recirculation) pipe.
Background:
The EGR pipe connect exhaust manifold to intake pipe for transportation of exhaust gas. Thus exhaust gas recirculation is required for reducing emissions
Conventionally, as shown in Fig. 1, the sealing flange 101 is formed out of the EGR pipe 200. The formed sealing flange 101 acts as a sealing for the joint. A mounting flange 100 is fitted on the extreme end of pipe 200. A fitment gap 300 is present in order to achieve a float fitting with the pipe 200.
Typically, in the working state, this design of flange integrated with the pipe is very weak in the bend zones and prone to failure.
Thus, to overcome the aforementioned deficiencies it is desirable to improve on the flange and pipe arrangement to improve upon the strength of the flange.
Objects of the Invention:
An object of the present invention relates to strengthening of the sealing flange used on EGR pipe for sealing with mating point.
Another object of the present invention is to strengthen the sealing of the joints.
Yet another object of the present invention is to reduce the tendency of failure of the sealing between the joints.
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Various modifications of the disclosed objects, as well as alternate objects of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present invention as defined.
Description:
To overcome the above deficiencies present in the conventional sealing flange, stronger sealing flanges are used in EGR pipes.
The present invention relates to strengthening of the sealing flange on the EGR pipe which mates with adjoining parts like exhaust manifold and intake pipe etc. The use of stronger sealing flange improves the life of the flange.
Fig. 2 exemplarily illustrates an EGR pipe used in exhaust gas circulation in accordance with one embodiment of the present invention. The sealing bush 400 is welded to the EGR pipe 200. Sealing bush 400, which is having high thickness than the EGR pipe 200 and also is stronger than EGR pipe 200 is welded to EGR pipe 200 is welded to the EGR pipe 200. Before this welding, mounting flange 600 that is floating on the sealing bush 400 by means of an achieved fitment gap 700 is inserted on the sealing bush 400. This concept ensures a sealing bush 400 with phenomenal strength coupled with a floating mounting flange 600. This arrangement also retains the floating concept of flange which helps in easy assembly of EGR pipe. The two bolt holes 500 in the mounting flange 600 are used to connect EGR pipe with the adjoining components like exhaust manifold.
3

Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present invention as defined.
Dated This 18th Day of June 2007
To T SRINIVASAN
The Controller of Patents AGENT FOR THE APPLICANT
The Patent office at Mumbai
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