FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION A System to Reduce Emissions of Vehicles
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
Dattatraya R Katkar and Deepak S Kulkarni 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:
This is invention relates to a device and an arrangement that helps in reducing emissions from the automobiles. More particularly, it relates to device that reduces the emissions during cold phase emissions of the vehicle by storing the cold phase engine out exhaust gases temporarily and releasing them when the catalytic converter is hot.
BACKGROUND OF INVENTION:
Rapid growth of economy coupled with growth in industry has resulted in growth in automotive population. This has also resulted considerable in emissions from the vehicles. Increase in the number & usage of vehicles concentrated in city area along with traffic congestion has resulted in even further increase in emissions. In order to address this problem automotive manufacturers are developing environmentally friendly vehicles, which will pollute less. However old & in use vehicles constitute a large portion of the vehicles. Similarly whether new or old vehicles, all the vehicles emit more amount of pollutants in cold phased of the engine. Hence, any attempts to improve the cold phase emissions will have a positive impact in reducing the vehicle out pollutants at a global scale.
PRIOR ART:
US patent 5419, 124 teaches a method for automotive internal combustion engine wherein, a hydrocarbon adsorber for the purpose of controlling the emissions of un burnt hydrocarbons from vehicle's tail pipe. Regeneration of adsorber achieved by an electronic engine controller operating an air pump and sample pump, using information from an exhaust gas oxygen sensor.
I IS patent 6263,666 Bl teaches a method in which exhaust emission control device of an engine comprises an NOx storage catalyst which traps and stores NOx in

exhaust gas and reduces the stored NOx according to an air fuel air fuel ratio of inflowing exhaust gas. A controller determines the conditions for discharging the SOx stored in the catalyst. When SOx discharge conditions are satisfied and the engine running conditions arc in a predetermined SOx discharge running region, the controller performs Sox discharge control of the catalyst. As lean air fuel ratio I is prohibited from when Sox discharge conditions are satisfied to when Sox discharge is complete , lean air fuel ratio control is prevented from taking place when the NOx trapping capacity of the catalyst is insufficient, and increase of exhaust emission is thereby prevented.
I, JS patent 5,746,984 teaches an exhaust system for a combustion system, comprising a device for collecling NOx , hydrocarbon , or particulate emissions, or mixture of these emissions and a plasma reactor for destroying the collected emissions is described. After the emission is collected in by the storage device for a period of time the, emission is then destroyed in a non thermal plasma generated by the plasma reactor. With respect to the direction of flow of the exhaust stream, the storage device must be located before the terminus of the plasma reactor, and it may be located wholly before, overlap with, or be contained within the plasma reactor. The above patents deal with storing one of more than one pollutant from the exhaust stream of an automotive exhaust. In the first case the unburnt hydrocarbon is adsorbed, where as in the second and the third patent, NOx, Sox are selectively stored. A separate and elaborate system is installed for this purpose. Even though these systems are useful these systems are costly. Similarly these systems can be sued only with certain new technology vehicles, and with minimum fuel requirements. Secondly, majority of vehicle population in any region is primarily in use vehicles. 1 he above mentioned techniques are not suitable for the in use vehicles with re old technology. The present patent aims at providing a system which helps in reducing the emissions for old as well as new vehicles which can be practically fitted on all vehicle irrespective of the fuel.


THEORY OF AUTOMOTIVE EMISSION CONTROL :
Modern automotive vehicles make use of advanced technologies such as common rail direct injection for Diesel & multipoint fuel injection for gasoline and gas applications. These vehicles essentially make use of a catalytic converter for the emission control. The size, specification & location of the catalytic converter are optimized for a given vehicle during the development phase. The cold phase engine out emissions primarily consist of un-burnt hydrocarbon and carbon monoxide due to incomplete combustion of the fuel. Any catalytic converter works satisfactorily and reduces pollution if,
1) The catalyst has attained a temperature higher than its light off temperature
2) Engine combustion system is function satisfactorily
3) Air-fuel ratio is maintained properly
4) Kngine combustion system is function satisfactorily
It also means that any vehicle will emit high amount of pollutants under cold conditions as well as during cranking. This effect is more serious for vehicles that are used for a short trips in which the distance traveled in catalyst cold condition is significant compared to total distance traveled in a trip.
Thus any attempt, in addition current automotive technology to reduce the cold phase duration during vehicle running will reduce the vehicle emissions
OBJECTS OF INVENTION:
The main object of the present invention is to store the exhaust gases in cold phase of vehicle operation and release the same when the catalytic converter is fully operational.


• Yet another object of the invention is to provide the exhaust gas storage device and an arrangement whose functioning and effectiveness is independent of engine condition and its parameters.
• Yet another object of the invention is to provide the exhaust gas storage device and an arrangement that improves the cold phase emissions and does not affect the engine and its control system.
• Yet another object of the present invention is to provide an add on device that can be retrofitted on in use vehicle.
• Yet another object of the present invention is to provide a simple and cost effective device to reduce the cold phase emissions from the vehicle.
SUMMARY OF INVENTION:
The present invention aims at reducing the vehicle out cold phase exhaust gases by storing the engine out exhaust gases temporarily in a separate chamber and releasing the same when the catalytic converter is fully functional. The storage chamber is located before the catalytic converter. The flow of exhaust gases into the chamber are controlled by an electronic controller through electrical solenoid valves. These gases arc released during engine idling, when the engine and the catalytic converter are warmed up. This ensures better conversion of the pollutants at the catalytic converter.
DESCRIPTION OF PREFFERED EMBODIMENTS:
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

The sketches showing details of the schematic and arrangement for the storage device
Tor cold exhaust gases for reducing the cold phase emissions from the vehicle are
given below.
Figure 1 shows the schematic arrangement of components of the exhaust system of
the vehicle.
figure 2 shows the schematic arrangement of exhaust system incorporating the
storage chamber for exhaust gases in accordance with this invention.
Figure 3 shows the schematic arrangement of exhaust system with exhaust gas storage
chamber and controlled recirculation.
Figure 4 shows the schematic details of the electronic controller which controls the
operation of external storage chamber for exhaust gases.
As shown in fig.l the exhaust system for an automotive vehicle comprises of an exhaust font pipe (1) to which the catalytic converter (2) is attached . The silencer (3) is connected to the downstream side of the catalytic converter. The location of the catalytic converter is decided based on vehicle packaging boundary conditions making every possible attempt to locate the catalytic converter as near the engine as possible. This is to ensure the faster warm up of the catalytic converter resulting in better conversion of the pollutants.
figure 2 shows the exhaust system for an automotive vehicle in accordance with the present invention. The system comprises of an exhaust font pipe (1) to which the catalytic converter (2) is attached. Silencer (3) is connected to the downstream side of the catalytic converter. The exhaust front pipe is provided with a Tee connection (21) which connects to a storage chamber (22). Exhaust gases coming out of the engine during cranking and during cold phase are stored into the storage chamber. Electrically operated butterfly valves (23) (24) & (25) are provided at the entry and exit of the storage chamber and just at the downstream of the Tee connection in the


main exhaust system, at the entry of the storage chamber and at the exit of the storage chamber respectively, control the storage and emptying operation of storage chamber. The operation of these solenoids is controlled by an electronic controller there by enabling filling and emptying of the exhaust gases.
figure 3 shows the schematic arrangement of exhaust system with exhaust gas storage chamber and controlled recirculation. The system is similar to the system as explained in fig. 2 and in addition, a connection is taken from the exhaust gas storage chamber (5) to the inlet manifold. This system functions similar to the system as explained in fig. 2 and in addition , allows a small fraction of the exhaust gas to be sent back to the engine enabling complete combustion of the un burnt hydrocarbons. The operation of these solenoids (),(),()&() is controlled by an electronic controller there by enabling filling emptying & recirculation of the exhaust gases.
figure 4 shows the schematic details of the electronic controller. The electronic
controller (41) is a microprocessor based unit capable of being programmed with
multiple variables and capable of receiving multiple inputs. It receives the following
inputs (42)
i) Engine stop signal
ii) Engine start signal
iii) Ambient air temperature
iv) Engine Coolant temperature
The engine stop signal triggers the electronic clock inside the controller and the clock counts the time since engine stop. Based on the engine coolant temperature, and the engine stop time, the electronic controller finds the temperature at the catalytic converter substrate. The temperature at the time of engine atop is treated as an initial temperature. Using these initial conditions, the electronic controller then predicts the


catalyst substrate temperature as a function of time since engine stop and the ambient temperature. A look up MAP is programmed into the electronic controller which helps in predicting the temperature at the catalyst substrate. The MAP uses a thermal cooling model for predicting the catalyst substrate temperature. The cooling of the catalyst substrate is also dependent on thermal mass of the catalyst and its surface area. These parameters decide values of variables in the MAP. The variables in the MAP are filled by experimental measurements and thus separate MAPs are required for different vehicle models.
Based on these inputs the controller checks whether, the instantaneous substrate temperature is lower than the light off temperature of the catalytic converter temperature. If the catalyst substrate temperature is lower than the light off temperature, the electronic controller opens butterfly () and closes butterfly (). Thus, the cold phase exhaust gases are stored in the storage chamber. After the engine is started the electronic controller slowly opens the butterfly valve () which is located in the main exhaust system. Thus the normal exhaust flow starts. Once the catalyst temperature goes beyond the light off temperature, the electronic controller opens the butterfly valve () and thus the storage chamber is emptied and the storage gases flow through the catalytic converter when the catalyst conversion efficiency is high, and if the catalyst substrate temperature is higher than the light off temperature, electronic controller closes the storage chamber and the cold phase exhaust gases are directly sent through the catalytic converter.
Similarly, if the system is configured as shown in fig. 3 , in such case, the electronic controller performs the exhaust gas storage operation as explained above and in addition, the electronic controller releases a small amount of stored exhaust gases in the inlet manifold when the engine becomes warm. Finally it also releases the remaining exhaust gases through the catalytic converter.


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.
Dated this 30th day of March 2009
TATA MOTORS LIMITED By their Agent & Attorney

Karuna Goleria of DePENNING & DePENNING