FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION "System & Method of Heating of Engine oil Sump for subzero starting"
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
Vishal V Gaikwad and Chandrashekhar V Kotulkar
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 THE INVENTION
The invention relates to a system and method of heating an engine and engine oil sump, more particularly for subzero temperatures.
BACKGROUND OF THE INVENTION
Many vehicles working in remote areas or in no mans land at different atmospheric conditions. In the Himalayan Mountains, Alaska, Siberia, Greenland, etc the temperature frequently drops below minus 35 degree centigrade, particularly during the nighttime. At such low temperatures the engine block and engine oil sump of a vehicle also drops into the subzero region. At such cold temperatures engines often fail to start and engine block heating is not sufficient to start the engine. Currently electrical oil sump heaters are available in the market. These heater, however, have numerous drawbacks.
AC current heaters are available, but require an external electrical supply, which is not available in remote areas. These heaters can be used where the electrical supply is there and is undisturbed.
The other available systems utilize DC current heaters. The available DC heaters which operate by means of a battery, but consume large amounts of power and therefore require additional batteries to be installed on the vehicle to make them operable. The additional weight of such batteries increases the load on the vehicle. Packaging of multiply batteries is also an issue, more space being required to for storage thereof. Consumption of power being high means the batteries drain faster.
Furthermore, in the currently available similar systems numerous modifications to the existing engine parts are necessary, which leads to additional space being required and a change in size of the oil sump.

With a view therefore to overcome the problems associated with conventional systems and methods of heating engine oil sump the inventors felt the need to develop a novel system and method for heating engine oil sump.
The basic errand of the present invention is to provide a novel system and method to heat engine oil sump and the engine block and engine head in cold starting application by utilizing the maximum amount of heat generated by a liquid.
In prior methods lots of modifications were required to be made to the existing engine parts, which will lead to extra space consumption in engine oil sump and requires change in dimension of the oil sump.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides a system of heating engine and engine oil sump, comprising a primary liquid heating circuit conveying a liquid coolant, said primary liquid heating circuit comprises,
- a liquid coolant heater having an inlet end and outlet end, for heating liquid coolant to a predetermined temperature,
- a primary pressure pump connected to said outlet end of said liquid coolant heater to facilitate circulation of a liquid coolant,
- a HVAC heater fed with said liquid coolant from said primary pressure pump to maintain said predetermined temperature,
- a secondary pressure pump for pumping the liquid coolant coming out from said HVAC heater through the engine and,
- a heat exchanger disposed between the said engine outlet and said inlet end of primary liquid heating heater for establishing a thermal connection with the engine oil sump.
The liquid coolant heater heats the coolant and circulates it through the engine when the engine is not running. Initially the coolant will be heated in the liquid

heater which will be then circulated through engine to heat the engine block, remaining heat in the coolant will be utilized to heat the engine oil sump before the coolant will again go back to the liquid coolant heater.
Preferably said primary liquid heating circuit is a closed circuit.
According to a particular embodiment of the invention, said system is provided with a secondary liquid cooling circuit, disposed between said outlet end of said engine and inlet end of said HVAC heater, for regulating the temperature of said liquid coolant within said engine sump when said liquid coolant exceeds said predetermined temperature.
According a preferred embodiment of the invention, said secondary liquid cooling circuit comprises, a thermostatic valve and a radiator, having inlet and outlet ends, said inlet end of said thermostatic valve being connected to said coolant outlet end of said engine, said thermostat outlet end being connected to a said radiator inlet end and said radiator outlet end being connected to said primary liquid cooling circuit at inlet end of said HVAC heater, said thermostatic value is configured to become active when temperature of said primary liquid heating circuit exceeds a predetermined temperature.
Desirably said secondary liquid cooling circuit is a closed circuit. The liquid contained within said liquid in said liquid coolant circuits may be water.
According to another embodiment of the invention said heat exchanger is disposed internally to the engine oil sump.
According to yet another embodiment of the invention said heater exchanger is integrally formed with said engine oil sump base.
A further embodiment of the invention provides that said heater exchanger is disposed around the engine oil sump.

According to still yet another embodiment of the said heater exchanger is formed of cooper.
According to still a further embodiment of the invention provides that said heat exchanger is in the form of a coil tube having an inlet and outlet end.
The present invention also provides a method for heating engine and engine oil sump to a predetermined temperature comprising the steps of; heating a coolant, circulating said coolant through a circuit thermally connected to said engine oil sump and regulating the temperature of said liquid coolant within the engine sump when temperature of said liquid coolant exceeds a predetermined temperature.
According to a particular embodiment of the invented method said coolant is circulated through a primary liquid cooling circuit for raising the temperature of said oil sump and through a secondary liquid cooling circuit when temperature of said liquid coolant exceeds a predetermined temperature.
According to a preferred embodiment of the invention said coolant is circulated through said primary liquid cooling circuit repeatedly until the coolant temperature reaches said predetermined temperature.
Preferably in the invented method said primary liquid cooling circuit comprises; a primary liquid heating circuit conveying a liquid coolant, said primary liquid heating circuit comprises;
a liquid coolant heater having an inlet end and outlet end, for heating liquid
coolant to a predetermined temperature,
- a primary pressure pump connected to said outlet end of said liquid coolant heater to facilitate circulation of a liquid coolant,
- a HVAC heater fed with said liquid coolant from said primary pressure pump to maintain said predetermined temperature,
- a secondary pressure pump for pumping the liquid coolant coming out from said HVAC heater through the engine,

- a heat exchanger disposed between the said engine outlet and said inlet end of primary liquid heating heater for establishing a thermal connection with the engine oil sump.
According to yet another embodiment of the invented method said secondary liquid cooling circuit comprises; a thermostatic valve and a radiator, having inlet and outlet ends, said inlet end of said thermostatic valve being connected to the coolant outlet end of the engine, said thermostat output end being connected to a said radiator inlet end and said radiator outlet end being connected to said primary liquid cooling circuit at inlet end of said HVAC heater, said thermostatic value is configured to become active when temperature of said primary liquid heating circuit exceeds a predetermined temperature.
Preferably said predetermined temperature is 60 degrees centigrade.
BRIEF DESCRIPTION OF THE DRAWINGS
For better understanding the illustrative embodiments of the invention will now be described with reference to the accompanying drawings. It will, however, be appreciated that the embodiments exemplifies in the drawings are merely illustrative and not limitative to the scope of the invention, because it is quite possible, indeed often desirable, to introduce a number of variations in the illustrative embodiment that has been shown in the drawings. It the accompanying drawings:
Figure 1 - schematically shows assembly of engine oil sump and portion of heat exchanger passing through the oil sump according to a particular embodiment of the invention.
Figure 2 - schematically a front view and a top view of the complete installation of portion of the heat exchanger within the oil sump according to the embodiment illustrated in figure 1.

Figure 3 - schematic exploded view showing arrangement of the portion of the
liquid cooling circuit and the oil sump base with fixtures according to the
embodiment illustrated in figures 1 and 2.
Figure 4 - schematically shows another embodiment of the heat exchanger,
disposed around the engine oil sump.
Figure 5 - schematically shows an exploded view of the embodiment of the heat
exchanger and engine oil sump as illustrated in figure 4.
Figure 6 - schematically shows a perspective view of the embodiment of the heat
exchanger, disposed integral to the engine oil sump.
Figure 7 - schematically shows an exploded view of the embodiment of the heat
exchanger and engine oil sump as illustrated in figure 6.
Figure 8 - is the hydraulic block diagram of the complete circuit illustrating the
working of the invented system according to a preferred embodiment.
DETAILED DESCRIPTION OF THE DRAWINGS
Figure 1 of the accompanying drawings shows assembly of engine (1) and oil sump (2) along with a portion of the heat exchanger i.e. a coil tube (3). The oil sump (2) is provided below said engine (1), and said coil tube is provided in said oil sump (2).
According to a particular embodiment illustrated in figure 2 said coil tube (3) is disposed within said oil sump (2). The coil tube (3) has an inlet port 5 and an outlet port (6). The inlet port (5) and outlet port (6) are provided on the same side of said oil sump (2). The inlet port (5) is provided above said outlet port (6) so that heating fluid can flow due to gravitation and heat up the oil easily. The coil tube (3) is rigidly mounted on the bracket (7-a) which is joined on the base of oil sump (2). Said joining can be the way of bolting or welding or any suitable method.
In another embodiment of the invention as illustrated in figures 4 and 5, said coil tube (3) is located externally to said oil sump (2), while in a further embodiment, as

illustrated in figures 6 and 7 said coil tube (3) is integrally formed with said oil sumps' 2 base part.
Referring to figure 3 of the accompanying drawing, the coil tube (3) is made up of three parts, wind tube (3-a), adapter boss (3-b) and hose connector (3-c). Coil tube (3-a) is made up of copper or aluminum as thermal conductivity of both these material is excellent and transfer heat with good rate. The adapter boss (3-b) and hose connector (3-c) is made up of stainless steel or carbon steel as thermal conductivity of both these material is very bad and transfer heat at very slow rate.
Shape of coil tube 3 has been designed in such a way that no pressure drop should occur due to bending, sudden enlargement or contraction of pipe or variation in cross section area.
Figure 3 shows the exploded view of the oil sump (2). All the assembled parts are shown in this diagram. The basic assembly consists of oil sump (2) with a base bracket (7-a), coil tube (3), a metallic clamp (7-b) which is bolted with bracket (7-a) with the bolt (7-c).
The oil sump (2) along with the copper tube (3) is installed on the engine (1) as shown in figure 1. As shown in figure 8 an external heater (8) is installed on the vehicle to heat the coolant from the engine cooling circuit. This heater can be of any type either fuel fired or electrical type. A coolant pump (9) is installed after heater to circulate hot coolant through engine circuit as well as through HVAC circuit.
The coil tube 3 is installed in the engine oil sump (2) to heat the oil sump at subzero temperature.
The working of the invention will now be explained with the aid of figure 8. Hot coolant will go to the engine block (1) as well as through HVAC heater (10) and return back to heater (8). The copper tube coil (3) is installed in the oil sump is

added in series in the same circuit. The hot water will circulate through the copper tube coil (3) to heat the engine oil sump utilizing maximum energy available in the hot coolant. This coolant will again go to the heater 8 and the cycle continuous till coolant temperature rises to 60° C and remains constant for few seconds. This circuit is the primary liquid heating circuit (14). Another circuit, the secondary liquid cooling circuit (15), disposed parallel to the primary liquid heating circuit (14), which consists of radiator (11) having thermostat (12) and an engine driven coolant pump (13). The coolant pump (13) functions only when engine (1) is running. This secondary liquid cooling circuit (15), i.e. the radiator circuit, starts functioning when coolant temperature rises to 80°C. Under such circumstance when the coolant temperature becomes as high as 80° C it is desirable to reverse the heating mechanism and engine oil temperature is reduced by circulating coolant through radiator (11). This reduces engine heat loss and increases engine efficiency or performance. To avoid direct heat transfer between oil sump and atmosphere at subzero temperature oil sump is painted with plastic or PVC paint.
The instant disclosure does not require any change in the shape of oil sump, rather utilizes the available space in the oil sump only. The disclosure put forth is designed not limited for heating of engine oil sump of the internal combustion engine. Advantageously the present disclosure can also be used to heat the remote oil tank or fuel tank.
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. A system of heating engine and engine oil sump, comprising a primary liquid heating circuit conveying a liquid coolant, said primary liquid heating circuit comprises:
- a liquid coolant heater having an inlet end and outlet end, for heating liquid coolant to a predetermined temperature,
- a primary pressure pump connected to said outlet end of said liquid coolant heater to facilitate circulation of a liquid coolant,
- a HVAC heater fed with said liquid coolant from said primary pressure pump to maintain said predetermined temperature,
- a secondary pressure pump for pumping the liquid coolant coming out from said HVAC heater through the engine and,
- a heat exchanger disposed between the said engine outlet and said inlet end of primary liquid heating heater for establishing a thermal connection with the engine oil sump.
2. The system of heating engine and engine oil sump as claimed in claim 1, wherein said primary liquid heating circuit is a closed circuit.
3 The system of heating engine and engine oil sump as claimed in any of the claims, wherein said system is provided with a secondary liquid cooling circuit, disposed between said outlet end of said engine and inlet end of said HVAC heater, for regulating the temperature of said liquid coolant within said engine sump when said liquid coolant exceeds said predetermined temperature.
4. The system of heating engine and engine oil sump as claimed in claim 3; wherein said secondary liquid cooling circuit comprises, a thermostatic valve and a radiator, having inlet and outlet ends, said inlet end of said thermostatic valve being connected to said coolant outlet end of said engine, said thermostat outlet end being connected to a said radiator inlet end and

said radiator outlet end being connected to said primary liquid cooling circuit at inlet end of said HVAC heater, said thermostatic value is configured to become active when temperature of said primary liquid heating circuit exceeds a predetermined temperature.
5. The system of heating engine and engine oil sump as claimed in claims 3 and 4, wherein said secondary liquid cooling circuit is a closed circuit.
6. The system of heating engine and engine oil sump as claimed in any of the above wherein the liquid in said liquid coolant circuit is water.
7. The system of heating engine and engine oil sump as claimed in any of the above claims, wherein said heat exchanger is disposed internally to the engine oil sump.
8. The system of heating engine and engine oil sump as claimed in any of the above claims, wherein said heater exchanger is integrally formed with said engine oil sump base.
9. The system of heating engine and engine oil sump as claimed in any of the above claims, wherein said heater exchanger is disposed around the engine oil sump.
10. The system of heating engine and engine oil sump as claimed in any of the above claims, wherein said heater exchanger is formed of cooper.
11. The system of heating engine and engine oil sump as claimed in any of the above claims 7 to 9, wherein said heat exchanger is in the form of a coil tube having an inlet and outlet end.
12. A method for heating engine and engine oil sump to a predetermined temperature comprising the steps of; heating a coolant, circulating said coolant through a circuit thermally connected to said engine oil sump and

regulating the temperature of said liquid coolant within the engine sump when temperature of said liquid coolant exceeds a predetermined temperature.
13. The method as claimed in claim 12; wherein said coolant is circulated through a primary liquid cooling circuit for raising the temperature of said oil sump and through a secondary liquid cooling circuit when temperature of said liquid coolant exceeds said predetermined temperature.
14. The method as claimed in claim 13; wherein said coolant is circulated through said primary liquid cooling circuit repeatedly until the coolant temperature reaches said predetermined temperature.
15. The method as claimed in claims 13; wherein said primary liquid cooling circuit comprises; a primary liquid heating circuit conveying a liquid coolant, said primary liquid heating circuit comprises;
a liquid coolant heater having an inlet end and outlet end, for heating liquid coolant to a predetermined temperature,
- a primary pressure pump connected to said outlet end of said liquid coolant heater to facilitate circulation of a liquid coolant,
- a HVAC heater fed with said liquid coolant from said primary pressure pump to maintain said predetermined temperature,
- a secondary pressure pump for pumping the liquid coolant coming out from said HVAC heater through the engine,
- a heat exchanger disposed between the said engine outlet and said inlet end of primary liquid heating heater for establishing a thermal connection with the engine oil sump,
16. The method as claimed in any of the claims 13 and 14; wherein said
secondary liquid cooling circuit comprises; a thermostatic valve and a
radiator, having input and output ends, said inlet end of said thermostatic
valve being connected to the coolant outlet end of the engine, said

thermostat output end being connected to a said radiator input end and said radiator output end being connected to said primary liquid cooling circuit at input end of said HVAC heater, said thermostatic value is configured to become active when temperature of said primary liquid heating circuit exceeds a predetermined temperature.
17. The method as claimed in any of the above claims; wherein said predetermined temperature is 60 degrees centigrade.