FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION
"DEMIST DUCT FOR INCREASING STIFFNESS OF INSTRUMENT PANEL"
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
Maneesh Arora , Sangeet Hari Kapoor
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
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FIELD OF INVENTION
The present invention relates to demist duct for increasing the stiffness of instrument panel in automobiles.
BACKGROUND
Demist / defrost mechanisms are employed in automobiles to clear the windscreen of the automobile of frost and mist. Demist / defrost mechanisms clear the frost and mist from a certain portion of the windscreen surface or the entire windscreen based on their arrangement. Demist / defrost mechanisms provided in automobiles need to meet international standards such as European homologation standard EEC 78/317.
The HVAC placed under the instrument panel occupy all the space available under the instrument panel and no stiffness member can be packaged below the instrument panel. The instrument panel, without any stiffness member to reinforce its strength, may not meet the reliability as required in an automobile.
But due to space occupied by the duct no stiffness member can be packaged below the instrument panel hence instrument panel might not meet the reliability as required in an automobile.
Hence there is need for designing a duct which will serve duel purpose; that is, not only it will remove the frost from the windscreen but also for provide stiffness to the instrument panel, thus increasing its strength.
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Objects of the Invention:
An object of the present invention is to provide a demist duct for giving strength to the instrument panel.
Another object of the present invention is to effectively remove frost and mist from the wind screen to meet the international standards.
Another object of the present invention is to target the hot air from the HVAC to the portion of the windscreen from which the frost or mist is to be cleared.
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:
Although demist duct 100 as shown in figure 1, figure 2 and figure 3 is simple in shape can not on its own provide strength to instrument panel. Figure 1 gives sectional line view of the demist duct. Figure 2 provides isometric pictorial view of the demist duct as seen from outlet side. Figure 3 provides isometric pictorial view of the demist duct as seen from inlet side. The air flow outlet 102 has wide cross section as compared to the cross section of the inlet 104. The increase in cross-section of the duct as depicted in figure 1, figure 2 and figure 3 results in a decrease in the air velocity instead of keeping the outlet air velocity either the same or more than the input air velocity. This reduces the effect of the hot air over the misty surface. It is desirable that the design of the demist
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duct should enable the hot air to be targeted to the windscreen. The demist duct should act as a nozzle and increase the velocity of the air coming from the HVAC as it hits the surface of the windscreen thereby clearing the fog and mist.
Further due to increase in outlet, the demist duct can not sufficiently provide the strength to instrument panel.
In order to improve the duct performance of its basic function and also to add stiffness to the duct at the outlet section, a baffle plate assembly 220 as shown in figure 4 with a plate 202 with baffles 210 is used. The plate 202 and the baffles 210 are made of the same or different material as that of the demist duct. The plate and the baffle assembly 220 are assembled with the duct 100 and the assembled condition is shown in figure 5, figure 6 and figure 7.
The use of the plate 202 with baffle assembly, attached to the duct 100, reduce the effective area for air flow keeping the outside geometry of duct same thereby adding strength to the instrument panel. Addition of extra material to the demist duct 100 enhances the strength of the demist duct 100.
Further, as depicted in figure 5, figure 6 and figure 7, the baffle leads to reduction in area at outlet. Figure 5 provides the details of the duct and baffle plate assembly in the sectional view. Figure 6 is a pictorial isometric view of the duct and baffle plate assembly as seen from inlet side. Figure 7 is a pictorial isometric view of the duct and baffle plate assembly as seen from inlet side. The baffles and plate assembly 220 divide the air flow only at source and hence cause it to hit the designated portion of the wind screen. As the area at outlet of the duct is reduced, velocity at the outlet gets amplified. Due to reduced
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outlet of the duct is reduced, velocity at the outlet gets amplified. Due to reduced outlet area, the hot air hits the surface of the windscreen at increased velocity thereby clearing the fog and mist more effectively.
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
The Controller of Patents
The Patent office at Mumbai
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