Claims:We claim:

1. A method for controlling temperature of cabin (Tcabin) of a vehicle, the method comprising:
determining, by a control unit (4) of the vehicle, parked condition of the vehicle based on a signal received from a locking module (3) associated with the vehicle;
determining, by the control unit (4), a difference in temperature between cabin temperature (Tcabin) and an ambient temperature (Tambient) based on signals received from one or more sensors (2), upon determining the parked condition of the vehicle;
comparing, by the control unit (4), the cabin temperature (Tcabin) with a predetermined threshold temperature (Tthreshold), when the difference in temperature between cabin temperature (Tcabin) and an ambient temperature (Tambient) is greater than a set temperature (Tset);
determining, by the control unit (4), state of charge of a power source (1) in the vehicle when the cabin temperature (Tcabin) is greater than that of the predetermined threshold temperature (Tthreshold);
operating, by the control unit (4), an exhaust fan (5) provided in the cabin of the vehicle for venting the air in the cabin to lower the cabin temperature (Tcabin), when the state of charge of the power source (1) is greater than a predetermined value of the state of charge of the power source (1).

2. The method as claimed in claim 1, wherein the operation of the exhaust fan (5) is terminated by the control unit (4) based on at least one pre-set parameters including lapse of pre-set time, state of charge of power source (1) falling below the predetermined value of the state of charge of the power source and drop in cabin temperature (Tdrop) below pre-determined temperature limit (Tlimit).

3. The method as claimed in claim 2, wherein the drop in temperature (Tdrop) of the cabin is a difference in temperature between a first cabin temperature and a second cabin temperature, wherein the first cabin temperature is determined before the operation of exhaust fan (5) and thesecond cabin temperature is determined after operation of the exhaust fan (5) is initiated.

4. The method as claimed in claim 2, wherein the predetermined temperature limit (Tlimit) ranges from 7 to 10 degree Celsius.

5. The method as claimed in claim 2, wherein the pre-set time for operating the exhaust fan (5) ranges from 25 to 35 minutes.

6. The method as claimed in claim2, wherein the pre-set threshold value of charge in the power source (1) ranges from 75% to 85%.

7. The method as claimed in claim 1, wherein the predetermined threshold temperature (Tthreshold) is 30 to 40 degree Celsius.

8. The method as claimed in claim 1, wherein the control unit (4) is configured to delay upcoming cycle of controlling the temperature of the cabin of the vehicle for a predetermined time after terminating operation of the exhaust fan (5).

9. The method as claimed in claim 8, wherein the pre-determined time ranges from 8 to 12 minutes.

10. A system for controlling a temperature of a vehicle cabin (Tcabin), the system comprising:
an exhaust fan (5) provided in the cabin of the vehicle;
a control unit (4) communicatively coupled to one or more sensors (2), a locking module (3) and power source (1) sensor, wherein the control unit (4) is configured to:
determine, parked condition of the vehicle based on a signal received from a locking module associated with the vehicle;
determine, a difference in temperature between cabin temperature (Tcabin) and an ambient temperature (Tambient) based on signals received from one or more sensors (2) upon determining the parked condition of the vehicle;
compare, the cabin temperature (Tcabin) with a predetermined threshold temperature (Tthreshold) when the difference in temperature between cabin temperature (Tcabin) and an ambient temperature (Tambient) is greater than set temperature (Tset);
determine, state of charge of a power of source (1) in the vehicle when the cabin temperature (Tcabin) is greater thanthat of the predetermined threshold temperature (Tthreshold);
operate, an exhaust fan (5) provided in the cabin of the vehicle for venting the air in the cabin and lowering the cabin temperature (Tcabin) when the state of charge of the power source (1) is greater than the predetermined value of the state of charge of the power source (1).

11. The system as claimed in claim 10, wherein the operation of the exhaust fan (5) is terminated by the control unit (4) based on at least one pre-set parameters including lapse of pre-set time, state of charge of power source (1) falling below the predetermined value of the state of charge of the power source and drop in cabin temperature (Tdrop) below pre-determined temperature limit (Tlimit).

12. The system as claimed in claim 11, wherein the drop in temperature (Tdrop) of the cabin is a difference in temperature between a first cabin temperature and a second cabin temperature, wherein the first cabin temperature is determined before the operation of exhaust fan (5) and the second cabin temperature is determined after operation of the exhaust fan (5) is initiated.

13. The system as claimed in claim 11, wherein the predetermined temperature limit (Tlimit) ranges from 7 to 10 degree Celsius.

14. The system as claimed in claim 11, wherein the pre-set time for operating the exhaust fan (5) ranges from 25 to 35 minutes.

15. The system as claimed in claim 11, wherein the pre-set threshold value of charge in the power source (1) ranges from 75% to 85%.

16. The system as claimed in claim 10, wherein the predetermined threshold temperature (Tthreshold) is 30 to 40 degree Celsius.

17. The system as claimed in claim 10, wherein the control unit (4) is configured to delay upcoming cycle of controlling the temperature of the cabin of the vehicle for a predetermined time after terminating operation of the exhaust fan (5).

18. The system as claimed in claim 17, wherein the pre-determined time ranges from 8 to 12 minutes.

19. A vehicle comprising a system for controlling temperature of cabin (Tcabin) as claimed in claim 1.

Dated 28th day of September2020

GOPINATH A S
IN/PA 1852
OF K&S PARTNERS
AGENT FOR THE APPLICANT
, Description:FORM 2
THE PATENTS ACT 1970
[39 OF 1970]
&
The Patents Rules, 2003

COMPLETE SPECIFICATION
[See section 10 and rule 13]

TITLE: “A METHOD FOR CONTROLLING TEMPERATURE OF A VEHICLE CABIN AND A SYSTEM THEREOF”

Name and address of the Applicant:
TATA MOTORS LIMITED, an Indian company having its registered office at Bombay House, 24 HomiMody Street, Hutatma Chowk, Mumbai 400 001, Maharashtra, INDIA.

Nationality: INDIAN

The following specification particularly describes the invention and the manner in which it is to be performed.

TECHNICAL FIELD

Present disclosure generally relates to the field of automobiles. Particularly, but not exclusively, the present disclosure relates to a method and a system for monitoring and controlling temperature of the vehicle cabin when the vehicle is in a parked condition. Further embodiments of the present disclosure disclose the method of controlling the temperature of the vehicle cabin by means of a fan mounted in the air extractor area of the vehicle cabin.

BACKGROUND OF THE INVENTION

When a vehicle is parked outdoors in the sun, the interiors or the cabin of the vehicle may be heated up to very high temperatures.The vehicle gets heated up from the outside as well as the inside when exposed to direct sun light for a prolonged period of time. The fundamental reason for the rise in temperature inside the cabin of a stand still vehicle is greenhouse effect. The sun rays entering through window panes and windshield cause the cabin of the vehicle to be heated up. Further, heat transfer from the surrounding to cabin through vehicle body conduction also leads to rise in temperature inside the cabin of the vehicle. Due to lack of ventilation, the air is stagnant and trapped inside cabin and the trapped air gets heated as mentioned above due to the sun rays and the heat transfer from the surroundings of the vehicle. Consequently, the trapped air results in rise of temperature of interior surfaces of the vehicle.

Further, when the driver or occupant enters the cabin of the vehicle, the hottrapped air in the cabin of vehicle imparts a scorching and unpleasantfeeling to the occupant. The hot trapped air in the cabin of the vehicle also transfers the heat to all the surfaces in the cabin of the vehicle. For instance, the steering wheel, the dashboard, the seats etc. in the cabin of the vehicle are heated to very high temperatures due to the trapped hot air. Further, the areas inside the cabin which are exposed directly to sun rays like the top surface of instrument panel and top area of steering wheel are likely to be the hottest and temperature of these surfaces may reach up to 90 degree Celsius. The temperature of surfaces of armrest, gear shifter knob and seat which are likely not subjected to direct sunrays but come in direct contact with occupant rise up to 65 to 75 degree Celsius.Consequently, the occupants find it difficult to touch theses surfaces and it becomes extremely uncomfortable for the occupants to be seatedin the cabin ofthe vehicle.

Under the above-mentioned circumstances, the occupants often tend to operate the air conditioning at maximum with openwindows or open doors. The occupants have to habituallywait for a couple of minutes till the temperature inside the cabin of the vehicle drops to a comfortable level, this may not be desirable.

Though the user may operate the air conditioning system for cooling the cabin, the various surfaces inside the cabin are already exposed to high temperatures. For instance, before the user turns on the air conditioning to cool the cabin, the various surfaces such as the dashboard, the steering, the seat are all subjected to endure very high temperatures from the hot trapped air. Consequently, the surfaces inside the cabin including the plastic/leather dashboard and various other surfaces of the cabin might lose their aesthetical appeal due to the high temperatures that the trapped air imparts on theses surfaces. Thus, the operational life of these materials in the cabin of the vehicle is drastically reduced by high temperatures.

The patent application “JP2005203135A” states that when vehicle is parked in summer, the temperature near instrument panel and windshield goes up to 90 degree Celsius. A ventilation device disclosed in the patent application forcibly exhausts the stagnant air inside instrument to outside of the vehicle panel that will further decrease the temperature of instrument panel surface. The device consists of switching box which switches the direction of flow when the air inside instrument panel is to be blown out and when the outer air is to be blown in. Further, the patent application discloses that the ventilation device operates on the basis of inputs from door lock release determining the approaching passenger, engine start/stop signal and temperature sensor determining the temperature inside vehicle.

Furthermore, US20170225541A discloses a forced-ventilation device using a smart entry system, which opens and closes vehicle door window panes. The system detects the presence of the user with help of mobile device/remote key and then only gets activated. The system uses existing HVAC blower in order to blow out the vehicle interior hot air by lowering the window glass. The system turns off the blower after predetermined time gets elapsed.

The above-mentioned documents disclose configurations where the cooling of the cabin is initiated only when the driver is approaching the vehicle or when the driver is inside the cabin of the vehicle. Therefore, the driver may have to wait for the cabin to be cooled to adequate temperatures before being seated inside the vehicle or the driver may have to temporarily endure the heat from the trapped air before the cabin is cooled. Further, the above-mentioned documents disclose the aspect of engaging the HVAC to cool the cabin of the vehicle. Consequently, the performance of the vehicle including mileage and battery is also affected due to initiation of the HVAC system for cooling of the vehicle.

The present disclosure is directed to overcome one or more limitations stated above, or any other limitation associated with the prior arts.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the conventional system or deviceare overcome, and additional advantages are provided through the provision of the method as claimed in the present disclosure.

Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In one non-limiting embodiment of the disclosure, a method for controlling temperature of in a vehicle is disclosed. The method includes the aspect of determining the parked condition of the vehicle by a control unit. The parked condition is determined based on a signal received from a locking module associated with the vehicle. A difference in temperature between cabin temperature and an ambient temperature is determined by the control unit, based on signals received from one or more sensors upon determining the parked condition of the vehicle. Further, the cabin temperature is compared with a predetermined threshold temperature when the difference in temperature between cabin temperature and an ambient temperature is greater than the set temperature. A state of charge of a power of source in the vehicle is determined whenthe cabin temperature is greater than that of the predetermined threshold temperature. Further, the control unit operates an exhaust fan provided in the cabin of the vehicle for venting the air in the cabin and lowering the cabin temperature when the state of charge of the power source is greater than a predetermined value of the state of charge of the power source.

In an embodiment of the disclosure, the operation of the exhaust fan is terminated by the control unit based on at least one of the pre-set parameters including lapse of pre-set time, state of charge of power source falling below the predetermined value of the state of charge of the power sourceand drop in temperature of the cabin below pre-determined limit.

In an embodiment of the disclosure, the drop in temperature of the cabin is a difference in temperature between a first cabin temperature and a second cabin temperature, wherethe first cabin temperature is determined before the operation of exhaust fan (5) and the second cabin temperature is determined after operation of the exhaust fan (5) is initiated.

In an embodiment of the disclosure the predetermined temperature limit ranges from 7 to 10 degree Celsius.

In an embodiment of the disclosure the pre-set time for operating the exhaust fan (5) ranges from 25 to 35 minutes.

In an embodiment of the disclosure, the pre-set threshold value of charge in the power source ranges from 75% to 85%.

In an embodiment of the disclosure, the predetermined threshold temperature is 30 to 40 degree Celsius.

In an embodiment of the disclosure the control unit is configured to delay upcoming cycle of controlling the temperature of the cabin of the vehicle for a predetermined time after terminating operation of the exhaust fan.

In an embodiment of the disclosure the pre-determined time ranges from 8 to 12 minutes.

In one non-limiting embodiment of the disclosure, a system for controlling the temperature of a vehicle cabin is disclosed. The system comprises of an exhaust fan provided in the cabin of the vehicle. A control unit is communicatively coupled to a plurality of temperature sensors, a vehicle parked condition sensor and a state of charge of the power source sensor, wherethe control unit is configured todetermine the parked condition of the vehicle. The parked condition is determined based on a signal received from a locking module associated with the vehicle. A difference in temperature between cabin temperature and an ambient temperature is determined by the control unit, based on signals received from one or more sensors upon determining the parked condition of the vehicle. Further, the cabin temperature is compared with a predetermined threshold temperature when the difference in temperature between cabin temperature and an ambient temperature is greater than the set temperature. A state of charge of a power of source in the vehicle is determined when the cabin temperature is greater than that of the predetermined threshold temperature. Further, the control unit operates an exhaust fan provided in the cabin of the vehicle for venting the air in the cabin and lowering the cabin temperature when the state of charge of the power source is greater than a predetermined value of the state of charge of the power source.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES

The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives,and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Fig. 1 is a schematic representation of a system for controlling the temperature of the vehicle cabin, in accordance with an embodiment of the present disclosure.

Fig. 2 and Fig. 3is a flowchart of the method of controlling the temperature of the vehicle cabin, in accordance with an embodiment of the present disclosure.

Fig. 4 is a graphical representation of the cabin temperature in the vehicle versus the ambient temperature, in accordance with an embodiment of the present disclosure.

Fig. 5 and Fig. 6 are graphical representation of the temperature at various different surfaces inside the cabin of the vehicle when an exhaust fan is in “ON” and ”OFF” condition, in accordance with an embodiment of the present disclosure.

The figure depicts embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the method for controlling the temperature of the vehicle cabin without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other system for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure. The novel features which are believed to be characteristic of the disclosure, as to its organization, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.

In the present document, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described below. It should be understood, however that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a system that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such mechanism. In other words, one or more elements in the device or mechanism proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the mechanism.

Embodiments of the present disclosure discloses a method for monitoring and controlling the temperature of the vehicle cabin. When a vehicle is parked outdoors in the sun, the interiors or the cabin of the vehicle may be heated up to very high temperatures.Further, when the driver or occupant enters the cabin of the vehicle, the hot trapped air in the cabin of vehicle imparts a scorching and unpleasant feeling to the occupant.Various surfaces such as the dashboard, the steering, the seat are all subjected to endure very high temperatures from the hot trapped air. Consequently, the surfaces inside the cabin including the plastic/leather dashboard and various other surfaces of the cabin might lose their aesthetical appeal due to the high temperatures that the trapped air imparts on theses surfaces. Thus, the operational life of these materials in the cabin of the vehicle is drastically reduced by high temperatures.

Accordingly, the present disclosure discloses a method for controlling the temperature of a vehicle cabin when the vehicle is in parked condition. The method includes the aspects of determining the parked condition of the vehicle by a control unit. The parked condition is determined based on a signal received from a locking module associated with the vehicle. Further, a difference between cabin temperature of the vehicle and an ambient temperature of the vehicle is determined by the control unit, based on signals received from one or more sensors upon determining the parked condition of the vehicle. Further, the cabin temperature is compared with a predetermined threshold temperature when the difference in temperature between cabin temperature of the vehicle and an ambient temperature of the vehicle is greater than the set temperature. A state of charge of power source in the vehicle is determined based on comparison of the cabin temperature and the predetermined threshold temperature upon determining that the cabin temperature is greater that the predetermined threshold temperature. Further, the control unit operates an exhaust fan provided in the cabin of the vehicle for circulating air in the cabin to lower the cabin temperature when the state of charge of the power source is greater than the predetermined value of the state of charge of the power source. The operation of the exhaust fan is terminated by the control unit when drop in temperature of the cabin is greater than or equal to the pre-determined temperature limit.

The following paragraphs describe the present disclosure with reference to Figs. 1 and 6.

Fig. 1 is a schematic representation of a system (100) for monitoring and controlling the temperature of the vehicle cabin. All the vehicles are defined with an air extractor area and the air extractor area allows the pressurized air inside the cabin of the vehicle to escape out to the atmosphere. Thus, the air extractor area inside the cabin of the vehicle allows for a suitable pressure to be maintained inside the cabin of the vehicle. The air extractor area may be positioned in one of the pillars or in the cargo compartment of the vehicle’s cabin. The dimensions and the positioning of the air extractor area largely depends on the volume of the vehicle’s cabin. The air extractor area/cut out may be suitably positioned inside the vehicle’s cabin depending on the air flow direction, the total volume of the cabin and other variables known in the art. The present disclosure discloses a configuration where an exhaust fan (5) is provided in the air extractor area of the cabin. The exhaust fan (5) operatesfor circulating air inside the cabin of the vehicle. In an embodiment, the rated power of the exhaust fan (5) may be 12 V and 0.5 Amp. Further, the exhaust fan (5) may operate at a speed of around 3000 rpm.The exhaust fan (5)may provide an air flow of 105 cubic feet/minute inside the cabin of the vehicle.The exhaust fan may forcibly blow stagnant and heated air inside the vehicle cabin, hence preventing the cabin temperature (Tcabin) to rise beyond a certain temperature.This way, there is also reduction in the rise in temperature of the interior surfaces.It should be noted that the specifications of the exhaust fan (5)mounted in the air extractor area may be varied based on various parameters including the volume of the cabin, the required rate of air circulation, the required rate of cooling for the cabin etc. without deviating from the scope of the present disclosure.

In an embodiment, any forced ventilation system known in the art may be provided in the air extractor area for circulating air inside the cabin of the vehicle.

The exhaust fan (5) may be communicatively coupled to a control unit (4) and the control unit (4) may initiate and terminate the operation of the exhaust fan (5). The control unit (4) may operate the exhaust fan (5) based on inputs from a plurality of sensors. Each of the plurality of sensors may indicate various parameters including the signals corresponding tostate of charge of a power source (1), the temperature signals from various temperature sensors (2) and the signals from a vehicle locking module (3).

The control unit(4) may be communicatively coupled to the power source (1) and a sensor or other suitable means may be coupled with the power source (1) such that the sensor transmits the signals corresponding to the state of charge of the power source (1). The power required for the operation of the exhaust fan (5) may be drawn from the power source (1) of the vehicle. In an embodiment, the power source (1) may be a solar panel or any other suitable source known in the art.

Further, the control unit (4) is coupled to a plurality of temperature sensors (2). The vehicle may be configured with at least one primary temperature sensor inside the cabin of the vehicle and the primary temperature sensor may transmit signals corresponding to the temperature of the cabin (Tcabin) to the control unit (4). Further, at least one secondary temperature sensor may be configured outside the cabin of the vehicle such that the secondary temperature sensor transmits the signals corresponding to the temperature of the atmosphere outside the cabin of the vehicle. The secondary temperature sensor may transmit signals of the temperature in the vehicle’s surroundings. This temperature may be referred to as the ambient temperature (Tambient). In an embodiment, the temperature sensors (2) may be mounted on multiple surfaces inside the cabin of the vehicle. The temperature sensors (2) may be mounted on door arm rest, the seat, parking brake lever, steering, gear knob, instrument panel and other suitable parts of the cabin.

The control unit (4) is communicatively coupled to a locking module (3) to check if the vehicle is in a parked condition. The locking module (3) consists of door lock/unlock sensor which may determine whether key is present inside/outside of the vehicle. The signals from the sensors of the locking module (3) are transmitted to the control unit (4) and the control unit (4) determines whether the vehicle is in a parked condition or not based on the received signals. When the signals corresponding to the door being locked and the key being outside the vehicle are received by the control unit (4), then the control unit (4) understands that the vehicle is in the parked condition. Any other combination of signals like door is unlocked and key is outside the vehicle or door is unlocked and key is inside the vehicle or door is locked and key is inside the vehicle, causes the control unit (4) to interpret that the vehicle is not in the parked condition. In an embodiment, any other means known in the art for detecting if the vehicle is in parked state should be considered as part of the present disclosure.

The control unit (4) receives the input signals from the above-mentioned plurality of sensors and accordingly initiates or terminates the operation of the exhaust fan (5) based on the input signals form the plurality of sensors. The method of cooling the cabin and maintaining suitable temperatures insidethe cabin by the control unit (4) of the vehicle is explained in greater detail below.

Fig. 2 and Fig. 3illustrate a flowchart of the method of monitoring and controlling the temperature of the vehicle cabin. Firstly, the control unit (4) at stage 21 of the flowchart, determines if the vehicle is in the parked condition or not. If the control unit (4) determines that the vehicle is not in the parked condition, then the condition at stage 21 (vehicle is parked) is concluded as false andthe system will wait till the condition at stage 21 is true. If the vehicle is found to be in parked state, the condition at stage 21 is true and the control unit (4) proceedsto stage 22.

At stage 22, the control unit (4) receives signals from the primary and the secondary temperature sensors. The corresponding cabin temperature (Tcabin) and the ambient temperature (Tambient) are determined by the control unit (4).Thecontrol unit (4) further calculates the difference in temperature between the cabin temperature (Tcabin) and the ambient temperature (Tambient), and the calculated difference temperature is further compared with a pre-determined temperature limit (Tlimit). The pre-determined temperature limit (Tlimit) may range from 7 to 10 degree Celsius.The pre-determined temperature limit (Tlimit) is preferably set to 8 degree Celsius. Further, the calculated temperature difference between the cabin temperature (Tcabin) and the ambient temperature (Tambient) is compared with the pre-determined temperature limit (Tlimit) at the stage 22. If the condition at stage 22 i.e. the calculated temperature difference between the cabin temperature (Tcabin) and the ambient temperature (Tambient) is greater than the pre-determined temperature limit (Tlimit) of 8 degree Celsius, then the control unit (4) proceeds to the stage 23. Further, if the condition at stage 22 is false, then the control unit (4)re-starts the cycle of controlling the temperature of the cabin by starting with stage 21 again. In an embodiment, the pre-determined temperature limit (Tlimit) may vary depending on the season and the location where the vehicle is operated. The above-mentioned condition at stage 22 is critical for preventing the exhaust fan (5) from being operated when the surrounding temperature or the ambient temperature (Tambient) is low. For instance, when the vehicle is in a parked condition after sunset, the ambient temperature (Tambient) or the temperature in the vehicle’s surrounding would be low and consequently, the cabin temperature (Tcabin) would also be low. Under such circumstances, there is no requirement for the cabin to be cooled. Further, if the ambient temperature (Tambient) is around 27 degree Celsius and the cabin temperature (Tcabin) is around 30 degree Celsius, the temperature difference between the cabin temperature (Tcabin) and the ambient temperature (Tambient) is3 degree Celsius. With further reference to the condition at stage 22, the calculated difference in temperature of 3 degree Celsius is not greater than the pre-determined temperature limit (Tlimit) of 8 degree Celsius, thus, the condition at stage 22 is concluded as false and the control unit (4) refrains from operating the exhaust fan (5). Therefore, the above-mentioned condition at stage 22 becomes critical in preventing the operation of the exhaust fan (5) when the ambient temperature (Tambient) is already low and when no cooling is required for the cabin of the vehicle.

Further, once the condition at stage 22 is true, the control unit (4) compares the cabin temperature (Tcabin) with a pre-determined threshold temperature (Tthreshold). The pre-determined threshold temperature (Tthreshold) may range from 30 to 40 degree Celsius and the threshold temperature (Tthreshold) is preferably set at 35 degree Celsius. Further, when the control unit (4) compares the cabin temperature (Tcabin) with a pre-determined threshold temperature (Tthreshold) and when the cabin temperature (Tcabin) is lesser than the pre-determined threshold temperature (Tthreshold) of 35 degree Celsius, the condition at the stage 23 is concluded as false and the control unit (4) restarts the cycle of controlling the temperature of the cabin by starting with stage 21 again. Further, if the cabin temperature (Tcabin) is greater than the pre-determined threshold temperature (Tthreshold) of 35 degree Celsius, the condition at stage 23 is concluded as true and the control unit (4) proceeds to the stage 24.

At the stage 24, the control unit (4) receives signals from a sensor coupled to the power source (1) and thecontrol unit (4) determines the state of charge in the power source (1). Further, the determined state of charge from the control unit (4) is compared with a pre-set threshold charge of the power source (1). The pre-set threshold charge of the power source (1)may range from 75% to 85% of the total state of charge of the power source (1). The pre-set threshold charge of the power source (1) is preferably set at 80%.If the current charge of the power source (1) is lesser than the pre-set threshold charge of the power source (1) at 80%, the condition at the stage 24 is concluded as false and the control unit (4) re-starts the cycle of controlling the temperature of the cabin by starting with stage 21 again. If the current charge of the power source (1) is greater than the pre-set threshold charge of the power source (1) at 80%, the condition at the stage 24 is concluded as true and the control unit (4) proceeds to the stage 25 where the operation of the exhaust fan (5) is initiated by the control unit (4). When the exhaust fan (5) is on, the trapped hot air inside the cabin is forced to move out of the cabin and fresh ambient air enters the cabin, thereby reducing the temperature inside the cabin.

The operation of the exhaust fan (5) is terminated by the control unit (4) based on at least one of the following three pre-set parameters.

With reference to the stage 26, the operation of exhaust fan (5) is terminated after a pre-set time. The pre-set time may range from 25 to 35 minutes and is preferably set at 30 minutes. Further, the pre-set time is calculated on the basis of cabin volume and air flow rate that may vary with respect to the vehicle. As indicated in the stage 26 of the flowchart, the operation of the exhaust fan (5) is terminated when the pre-set time of 30 minutes is reached. When the exhaust fan (5) operates for a time period greater than or equal to the pre-set time of 30 minutes, the control unit (4) terminates the operation of the exhaust fan (5).The control unit (4) at stage 27, checks for the state of charge of the power source (1) after the operation of the exhaust fan (5) is initiated. In an embodiment, if the current state of charge of the power source (1) drops below a pre-set threshold value of charge in the power source (1), the operation of the exhaust fan (5) is terminated by the control unit (4). As mentioned above, the pre-set threshold value of charge in the power source (1) may range from 75% to 85% of the total state of charge of the power source (1). The pre-set threshold charge of the power source (1) is preferably set at 80%. Further, if the current state of charge in the power source (1) drops below the pre-set threshold value of 80%, the control unit (4) terminates the operation of the exhaust fan (5). The condition at stage 27 ensures that the state of charge in the power source (1) is not excessively drained by the operation of the exhaust fan (5).

Further, the control unit (4)at stage 28, compares a drop in temperature (Tdrop) inside the cabin with the pre-determined temperature limit (Tlimit).As mentioned above, the pre-determined temperature limit (Tlimit) may range from 7 to 10 degree Celsius and the pre-determined temperature limit (Tlimit) is preferably set to 8 degree Celsius.The drop in temperature (Tdrop) of the cabin is a difference in temperature between a first cabin temperature and a second cabin temperature. The first cabin temperature is the temperature of the cabin before the operation of exhaust fan (5) is initiated and the second cabin temperature is the temperature of the cabin after the operation of the exhaust fan (5). When the calculated drop in temperature (Tdrop) is greater than or equal to the pre-determined temperature limit (Tlimit) of 8 degree Celsius, the control unit (4) terminates the operation of the exhaust fan (5). The operation of the exhaust fan (5) is initiated by the control unit (4) when temperature of cabin (Tcabin) is greater than the threshold temperature (Tthreshold) of 35 degree Celsius (first cabin temperature). Further, the operation of the exhaust fan (5) is terminated by the control unit (4) when the drop in temperature (Tdrop) is greater than or equal to the pre-determined temperature limit (Tlimit) of 8 degree Celsius. For instance, the operation of the exhaust fan (5) is initiated when the temperature of cabin (Tcabin) is around 35 degree Celsius (first cabin temperature) and the operation of the exhaust fan (5) will be terminated only when the temperature of cabin (Tcabin) reaches to around 27 degree Celsius(second cabin temperature) as the temperature drop (Tdrop) from 35 degree Celsius to 27 degree Celsius is 8 degree Celsius and this temperature drop (Tdrop) is equal to the pre-determined temperature limit (Tlimit) of 8 degree Celsius. Further, the operation of the exhaust fan (5) may also be terminated when the temperature of cabin (Tcabin) drops to a value lower than 27 degree Celsius as the value of the temperature drop (Tdrop) would be lesser than the pre-determined temperature limit (Tlimit).

If any one of the above-mentioned conditions at stages 26, 27 and 28 are true, the control unit (4) proceeds to the stage 29 where the operation of the exhaust fan (5) is terminated.

Once, the operation of the exhaust fan (5) is terminated, the control unit (4) proceeds to stage 30. The control unit (4) at stage 30 is configured to delayupcoming cycle of controlling the temperature of the cabin of the vehicle by a pre-set time delay. The pre-set time delay may range from 8 to 12 minutes and is preferably 10 minutes. The cycle of controlling the temperature of the cabin is re-initiated once the time delay of 10 minutes is achieved.

Fig. 4 is a graphical representation of the cabin temperature (Tcabin) in the vehicle versus the ambient temperature (Tambient).The temperature of the various surfaces inside the cabin e.g. steering wheel (b), gear knob (d) etc. is always higher than the ambient temperature (Tambient) due to the trapped air (h). The trapped air (h)inside the cabin absorbs the heat from the surroundings and the heat from the trapped air (h) is further transferred to the various surfaces in the cabin of the vehicle. For instance, when the ambient temperature (Tambient) is around 38 degree Celsius, the temperature of the cabin (Tcabin) would be around 60 degree Celsius as clearly seen from the graph and this significant difference in temperature between the cabin air (h) and the ambient temperature (Tambient) is due to the trapped air (h). The graph from Fig. 3 also shows the temperature of various surfaces such as the steering wheel (b), gear knob (d), driver’s seat (c), door arm rest (e) etc. for a particular given ambient temperature (Tambient). It is evident from the graph that the temperature inside of the cabin (Tcabin) and the temperature of various different surfaces of the cabin are drastically high when compared with any particular given value of the ambient temperature (Tambient).

Fig. 5 and Fig. 6 are graphical representation of the temperature at various different surfaces inside the cabin of the vehicle when the exhaust fan (5) is in “ON” and ”OFF” condition. The temperature curve of the cabin and various other surfaces inside the cabin are indicated by “X” when the exhaust fan (5) is in OFF condition. The temperature curve of the cabin and various other surfaces inside the cabin are indicated by “Y” when the exhaust fan (5) is in ON condition. It is evident from the graphs that the temperature of the cabin air is lesser when the exhaust fan (5) is in ON condition. A temperature difference of almost 8 degree Celsius is observed when the exhaust fan (5) is ON and when the exhaust fan (5) is OFF. Further, a significant difference in temperature is also observed on various surfaces of the cabin when the exhaust fan (5) is ON and when the exhaust fan (5) is in OFF condition. For instance, the temperature of the surface of the parking brake lever is found to be around 68 degree Celsius when the exhaust fan (5) is in OFF condition and the temperature of the parking brake lever is found to be around 57 degree Celsius when the exhaust fan (5) is in ON condition. It is therefore observed that operating the exhaust fan (5) in the above-mentioned method reduces the temperature of the cabin air and the temperature of the various surfaces inside the cabin of the vehicle. The Fig. 4 and Fig. 5 also illustrate the temperature comparison of various surfaces such as instrument panel, door arm rest, gear knob, steering wheel, driver’s seat when the exhaust fan is in ON and OFF condition. It is observed in these graphs that the above-mentioned method allows for a significant reduction in cabin temperature (Tcabin).

In an embodimentof the disclosure, the above-mentioned method reduces thetemperature of cabin (Tcabin) andenables the occupants or the driver to comfortably access the cabin of the vehicle.

In an embodiment of the disclosure, the above-mentioned method of controlling the temperature of cabin (Tcabin) prevents the premature deterioration of the various surfaces inside the cabin.

In an embodiment of the disclosure, the above-mentioned method reduces the temperature of cabin (Tcabin) without the requirement for lowering the windows or opening the doors of the vehicle for cooling of the cabin.

In an embodiment of the disclosure, the above-mentioned method reduces the temperature of cabin (Tcabin) without the activation of the HVAC system and thereby improves the overall performance of the vehicle.

In an embodiment of the disclosure, the above-mentioned method reduces the temperature of cabin (Tcabin) without having the user to wait for the cabin to be cooled.

Equivalents

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding the description may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated in the description.

Referral Numerals:

Referral numerals Description
1 Power source
2 Temperature sensors
3 Locking module
4 Control unit
5 Exhaust fan
Tcabin Cabin temperature of the vehicle
Tambient Ambient temperature
Tthreshold Threshold temperature
Tlimit Pre-determined temperature limit
Tdrop Drop in temperature of the cabin