FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10; rule 13)
TITLE OF INVENTION An Arrangement To Improve Engine Warm Up
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
Mr. Dattatraya R. Katkar, Mr. Deepak S. Kulkarni
Both are 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 invention relates to a device and an arrangement that improves the warm up performance of the engine after a cold start. More particularly, it deals with the auxiliary means of heating engine oil and engine coolant so that engine warm up is achieved faster
BACKGROUND OF INVENTION
Automotive engines and vehicles are designed and optimized to deliver optimum performance under certain operating conditions. One such condition from engine point of view is engine operating temperature. When the engine coolant temperature and the engine oil temperature is within a specific temperature range the engine delivers optimum performance from power delivery and fuel economy point of view. The engines out emissions are also optimum under this operating condition. However, the engines and vehicles can not operate under warm up conditions for all the time. When the vehicle is long soaked for a long time the engine oil and coolant attain ambient temperature. When the vehicle is started in such condition, the engine takes certain finite time to warm up and attain the steady state where in the engine performance is optimum. When the ambient is cold or in extreme winters the engine warm up period is prolonged. Engine warm up is also prolonged under short trips.
During the warm up period the engine performance and fuel economy is sub optimum. The engine performance can be improved if the engine warm is achieved faster.
Theory Of Engine Cold Phase Operation
Automotive vehicles are designed by deliver optimum performance during warmed up condition. The engine performance in terms of power and fuel consumption is sub optimum when the engine is running under cold conditions. Engine power is less since the friction is high. This also results in higher fuel

consumption. The engine emissions are also high during cold phase operation. The engine cold operation results in penalty in terms of fuel consumption and emission. The engine gets warmed up due to heat generated due to combustion inside the engine. The rate of engine warm up depends upon the rate of heat generation & the thermal inertia of the system. The warm up of an engine can be increased if any auxiliary heating is provided to the engine systems, the warm up of the engine will be faster. The present invention aims at using engine exhaust heat to warm up the engine.
PRIOR ART
US patent 4391235 teaches a method of heating liquid coolant of liquid cooling system of an engine in motor vehicle is heated by using hot exhaust gas emitted by the engine. The heat exchanger transfers the heat from the hot exhaust gases to the coolant. A portion of the coolant is transferred from the engine cooling system to the heat exchanger & back to the engine. A diverted valve actuated by the temperature sensing device diverts the exhaust gas from an exhaust system to the heat exchanger. The temperature sensing device actuates a diverter valve at a predetermined coolant temperature diverting the exhaust gas to the heat exchanger when the coolant is cold & shut off the flow of the exhaust gas to the heat exchanger when coolant is sufficiently warm.
US patent 4685430 teaches a method of providing a heat exchanger comprising a fluid box having the ends of tubes opening out therein, said tubes constituting a heat exchange bundle located inside an envelope. Engine exhaust gases flow the said box and said tubes and the engine cooling liquid or cabin heating air flow through said envelope. The envelope is connected to the fluid box by a tubular element and a perforated plate. The envelope is made up pf light weight material which need not be capable of withstanding exhaust gas temperatures.
It is clear from the above description that, the first patent makes use of the heat energy of the exhaust gas to heat the engine coolant. A separate heat exchanger provided outside the engine for this purpose & part of coolant is circulated through

heat exchanger. Such an arrangement calls for transferring a part of engine coolant out of the engine cooling circuit. Similarly such an arrangement introduces extra hoses, hose joints which may to leakage, additional pumping work.
The second patent also makes use of a separate U tube type heat exchanger to a heat the engine coolant and or cabin heating air. The engine coolant and or the cabin heating air is transferred to the heat exchanger.
Both these arrangements call for transferring a part of engine coolant out of the engine cooling circuit. Similarly such an arrangement introduces extra hoses, hose joints which may to leakage, additional pumping work. Similarly, these patents do not deal with heating of engine oil which has significant contribution on engine warm up, friction etc.

These limitations can be overcome if the heating is carried out in situ (without involving movement of engine fluids). Such an arrangement results in faster & efficient heating of cold engine coolant. The present invention aims at heating cold engine coolant & cold engine oil in situ using heat from exhaust gas which directly transfers the heat to engine fluids through a heat exchanger.
OBJECTS OF INVENTION
Main ob ect of the present invention is to provide a device & an arrangement that increase the rate of engine warm up by supplying heat to the engine oil and engine coolant during engine cold operation.
Yet another object of present invention is to provide the heating to the
engine coolant & water from the engine exhaust heat which otherwise goes

waste.
Yet another object of present invention is to provide a system & an
arrangement that does not draw power from the engine for its operation.

. Vet another object of the present invention is to provide a device & an arrangement that comes into action automatically and did not enter with engine operation.
• Yet another object of the present invention is to provide a device & an arrangement that is simple and cost effective.
SUMMARY OF INVENTION
The present invention aims at providing an external heating to the engine oil & engine coolant during cold running of the engine. The external heating is provided using heat from the engine exhaust gases. A part of exhaust gases are diverted from the front pipe to heat engine oil & engine coolant and then finally discharged into the exhaust system before catalytic converter. The exhaust gases are passed through heat exchangers which are suitably fabricated to has heat transfer to engine oil & engine coolant. The flow of exhaust gases into the engine oil and coolant heat exchanger is controlled through electrically operated solenoid, which are controlled by an electronic controller.
STATEMENT OF INVENTION
Accordingly the invention provides an arrangement to improve engine warm up by heating engine coolant comprising;
a thermostat configured for mounting on engine coolant outlet to sense engine coolant temperature;
solenoids configured to control the flow of exhaust gas in the heat exchanger through controlling device;
an engine coolant heating system configured for heating engine coolant comprising;
heat exchanger with fins facilitated for optimizing heat transfer rate which is constructed on water bypass pipeline carrying said engine coolant.
Accordingly the invention further discloses an arrangement to improve engine warm up by heating engine oil comprising;

an oil sump modified to adapt the tubes carrying exhaust gas configured to be immersed in oil completely;
solenoids configured to control the flow of exhaust gas in said tubes through controlling device;
at least two headers located outside oil sump configured for distribution and collection of exhaust gas through said tubes of oil sump.
BRIEF DESCRIPTION OF DRAWINGS
The sketches showing details of the arrangement of the instant invention given
herewith.
Fig. 1 shows the oil & coolant heating system in accordance with the present
invention. Fig. 2 shows the details of the oil heating arrangement in accordance with the present
invention. Fig. 3 shows the engine coolant heating system in accordance with the present
invention. Fig. 4 shows the schematic details of the electronic controller that controls the engine
oil & coolant heating device.
DETAILED DESCRIPTION OF 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.
As shown fig. 1, the water pump (1) is mounted on the cylinder block (2). Thermostat (3) is mounted at the outlet of engine coolant from the engine. Water by pass line (4) carries the engine coolant back to the water pump. Engine coolant flows through the water by pass line when the engine coolant temperature is low and the thermostat has not opened. The engine coolant heating system comprises

of a tube in tube heat exchanger (5) fabricated on the water by pass line (4) . The construction of heat exchanger is such that the water by pass line forms the inner tube & exhaust gas carrying tube forms outer tube. Exhaust gas inlet (6) and outlet (7) are provided on the outer tube. The engine coolant gets heated due to heat transfer from exhaust gases. The flow of exhaust gases into the heat exchanger is controlled by the electrically operated solenoids (not shown) through an electronic controller.
The oil sump (8) stores engine oil. The oil sump is modified to receive tubes (9) which carry exhaust gases. The tubes are located in such way that they are dipped into the oil completely even with minimum oil quantity in the sump & do not cause any obstruction to normal oil flow. Headers (11) & (12) are provided at the entry and exit of these tubes outside the oil sump. The engine oil gets heated up due to heat transfer from exhaust gases. The flow of exhaust gases into these tubes is controlled by an electronic controller through electrically operated solenoids.
The other functioning of engine cooling circuit and engine lubricating circuit remains unchanged.
As shown in fig. 2 the engine oil heating arrangement comprises of an oil sump (8) which is modified to carry the tubes(9). These tubes are curved in shape so as to increase the exhaust gas residence time. The tubes are provided with fins (10) finned from outer side so as to improve the heat transfer to the oil. These fins are of detachable type. Headers (11) & (12) are provided at the inlet and outlet of the tubes. These headers facilitate distribution and collection of the exhaust gas.
As shown in figure 3, the engine coolant heat exchanger comprises of a tube in tube heat exchanger which is formed on the water bypass tube. Water bypass tube (4) forms the inner tube of the heat exchanger. The outer tube (31) carries exhaust gas. Inlet connection (32) and outlet connection (33) is provided on the outer tube considering the vehicle packaging. The inlet and outlet are located in such a way that it forms a counter flow heat exchanger. Baffles (34) are provided on the inner side of the outer tube so that the residence time of the exhaust gas is increased. The

water bypass tube ( in the portion of the heat exchanger) carries fins (35)on the outer side so that the heat transfer rate is improved.
Fig. 4 shows the schematic details of the electronic controller that controls the engine oil & coolant heating using heat of the exhaust gas. The electronic controller (41) receives following inputs (42).
• Engine start signal.
• Engine coolant temperature.
• Engine Stop signal.
After receiving the engine start signal, the electronic controller checks the engine coolant temp. The controller has engine thermal model (43) built in it. It predicts the engine oil temperature based on the engine coolant temperature. Based on these inputs and programmed parameters, the electronic controller decides the operation of exhaust gas flow control solenoids (44).
If the engine coolant temperature is less than a set threshold, the electronic controller operates the exhaust gas supply solenoids & starts the exhaust gas supply to engine coolant as well as engine oil heat exchangers. Once the engine coolant temperature and in turn the engine oil temperature reaches the threshold, the exhaust gas supply is stopped.
Once the engine is topped, the electronic controller predicts the engine coolant and engine oil temperature based as a function of time and the ambient air temperature. This thermal mode is engine & vehicle dependent and needs to be validated for vehicle model and entered as a programmed parameter (43) into the controller.
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.

WE CLAIM
1. An arrangement to improve engine warm up by heating engine coolant
comprising
a thermostat configured for mounting on engine coolant outlet to sense engine
coolant temperature;
solenoids configured to control the flow of exhaust gas in the heat exchanger
through controlling device;
an engine coolant heating system configured for heating engine coolant
comprising;
heat exchanger with fins facilitated for optimizing heat transfer rate which is
constructed on water bypass pipeline carrying said engine coolant.
2. An arrangement to improve engine warm up by heating engine oil comprising;
an oil sump modified to adapt tubes carrying exhaust gas configured to be
immersed in oil completely;
solenoids configured to control the flow of exhaust gas in said tubes through
controlling device;
at least two headers located outside oil sump configured for distribution and
collection of exhaust gas through said tubes of oil sump.
3. The arrangement as claimed in claim 1, wherein said heat exchanger is a counter flow type of heat exchanger having a outer concentric tube for carrying exhaust gas having exhaust gas inlet and outlet ports.
4. The arrangement as claimed in claim 1, wherein said outer concentric tube is provided with baffles from inner side to increase residence time of said exhaust gas in said heat exchanger.
5. The arrangement as claimed in claim 1, wherein said water bypass line portion covered with said concentric tube is finned from outer side for optimizing heat transfer rate.

6. The arrangement as claimed in claim 2, wherein said tubes are curved to increase the exhaust gas residence time and increase heat transfer.
7. The arrangement as claimed in claim 2, wherein said tubes are finned for optimizing heat exchange process and headers are provided at the inlet and outlet.
8. The arrangement as claimed in claim 1 and 2, wherein said exhaust gas controlling through controlling device is controlled on basis of the engine coolant temperature inputs.
9. The arrangement as claimed in claim 1 and 2, wherein said controlling device is provided with engine thermal model configured to sense engine coolant temperature to operate said solenoids.
10. The arrangement to improve engine warm up by heating engine coolant substantially as herein above described and as illustrated in accompanying drawings
Dated this 17th day of March 2009
TATA Motors Limited By their Agent & Attorney

(Karuna Goleria) of De PENNING & De PENNING