FORM 2
THE PATENT ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
PROVISIONAL SPECIFICATION
(See section 10 and rule 1:


1. TITLE OF THE INVENTION
AN AIR COOLING SYSTEM WITH SELF IRRIGATING PADS
2. APPLICANT
MAHINDRA & MAHINDRA LTD.
1, GATEWAY BUILDING, APOLLO BUNDER, MUMBAI - 400001. AN INDIAN COMPANY.


The following specification describes the invention.

Field of the Invention
The present invention relates to a compact air cooling system with self irrigating pads for diverse applications including for use in off-road vehicles. In particular, the present invention relates to evaporative cooling system for providing conditioned air for the comfort of a tractor operator.
Background of the Invention
Properties of air such as temperature and humidity are changed in any air cooling system for human comfort. There are diverse types and means to regulate temperature and / or humidify of air to achieve desired condition of air for comfort. In one of the means, known as evaporative cooling, latent heat of evaporation of water which is introduced into a stream of air is used to cool the air stream. Either water is introduced in the air stream or air stream is passed through the contacting device generally known as evaporative pads that are irrigated with water. A flow of air is directed into the wetted pad to cause evaporation of the water absorbed by the pad. The evaporated water is carried in the air passing through the pad element thus humidifying and further cooling air.
Conventional used evaporator working mechanism comprises of water storage tank wherein the water is circulated using water pump to the cooling pads. The water circulation mechanism keeps the pads wet during operation of the system. To control and operate these mechanisms other supportive mechanisms are used such as the water float sensors to control the water level, switch to on-off the water pump. However, a water pump is necessary in these conventional systems to irrigate the said pads. It is necessary to supply water to the said pads consistently in tandem with flow of air across the pads. This needs water pump.
Off road vehicles such as tractors and construction equipment operate extensively in the field. Generally, these vehicles are not provided with operator enclosed cabin due to which the operator is subjected to adverse climate conditions. Similarly, stationary applications or work such as operation, maintenance/ repair work for genset and such equipment, requires operator to work for considerably

longer periods in open, hot areas or adverse climate conditions. There is a need to provide comfort conditions to the operator by using air cooling system. Though conventional air cooling systems may be used, it would need extensive ducting and redesigning of the cabin to accommodate and operate conventional air-cooling systems under such operating conditions.
It is therefore desirable to provide compact air cooling systems especially for off-road vehicles that have to be operated under varying field conditions. Further the air-cooling system should ideally be installable in existing vehicles without substantial modification of the vehicle cabin design.
Prior art provides a host of examples of air cooling systems that may be adapted for use in applications indicated above.
US Patent 5775580 discloses an evaporative cooling system The device includes psychrometric sensors installed in the air stream at an evaporation pad which provide signals to a control device. The stream of air is cooled by one or more mist nozzles in the incoming air stream, the flow of water to which is controlled through analog or digital control devices, enabling cooling of the stream of air to the maximum permitted by psychrometric relationships without unnecessarily high humidity or overwetting of the evaporative pad.
US Patent 6895772B2 discloses an evaporative cooler that has multi sided cabinet with individual evaporative cooling pads These cooling pads are sandwiched between the door and the wire mesh. This makes the replacement very difficult. Due to involvement of oscillating and rotatable spout on the top, separate water sump and mechanism to deliver the water on the cooling pads makes the overall system very complex, heavy and not a stand alone system.
US Patent 2,223,884 discloses an evaporative cooling unit used on an automobile. There is no driven cooling fan of any kind because stream of the moving automobile creates the air flow through a wetted cooling pad. There is a movable air duct to direct cooled air to a predetermined location.

JP2006310766A/2006-10-19 describes an indirect type of evaporative cooling device for air-conditioner that has corrugated boards joined through plastic films such that water drawn into the stack of boards from a water sump, is vaporized by supplying dry air through holes in specific locations in the stack of boards. The construction is fairly complex. If such a system is to be used especially in an off-road vehicle, the cabin will need to be modified extensively due to the inflexibility of the directions of the air flows specifically dictated by the geometry of the construction of the assembly of the stacked boards..
US 6,895,772 discloses an evaporative cooling device. It comprises of evaporative pads, blower and water pump that delivers water from the water tank to channels provided on each cooling pads to sprinkle the water on each cooling pads fixed vertically in each opening of housing.
US Patent 2,793,015 utilizes a spray nozzle to inject water from a reservoir into the incoming warm air. The spray may also wet a pad formed into vertical separated wafers, with the incoming air flowing between. A device disclosed in US Patent No. 2,342,841 discloses the concept of using spray nozzles to introduce water for evaporation.
United States Patent 6112538 discloses a portable evaporative cooling system that includes a liquid storage tank, a pump coupled to the tank and a power source coupfed to the pump. In addition, the system includes one or more nozzles coupled to the pump for converting a liquid to a relatively fine mist. The pump pumps the liquid from the tank to the one or more nozzles in a substantially non-pulsating manner, thereby providing a substantially continuous misting.
United States Patent 3583174 discloses evaporative air cooler for cabs. It includes a tank for water to be evaporated by a cylindrical porous pad which is pumped to a self-operated circulating nozzle; air to the vehicle cab being drawn through the pad and into the cab along a conduit in heat-exchanging relationship to the water supply.

United States Patent 4360368 discloses Air-conditioner employing the evaporation of water for a cab of a machine or vehicle. It comprises a turbo-fan unit directly mounted against an evaporation chamber. Inside the latter, a box facing the air inlets conditions the air distributed toward water injection nozzles and ensures the seal on the upstream side of the chamber.
United States Patent 4968457 discloses a Non-circulating water system for evaporative coolers. It incorporates a timing means in conjunction with a valve means, to control the flow of water to the pads. It applies measured amounts of water to the pad and allows measured amounts of time between applications so that most of the water is used in the evaporation process and minimal amounts of water are discharged though a drain.
US Patent 6575436 discloses evaporative cooler. It comprises of a fan, evaporative pad, a conduit and flow control system that is provided to supply evaporation water to the evaporative pad at a rate substantially equal to the rate at which the water evaporates from the pad.
The study of the related aforementioned prior art reveals that each of the system needs water circulating means such as water pump to irrigate water on the cooling / evaporative pads. A water control system is necessary to control flow of water to the pads. Some of the systems that do not use water pump to irrigate the cooling pads, the construction is rather complex with inflexibilities in the directions of the airflow thereby necessitating design changes of the vehicle cabin especially in the case of off-road vehicles such as tractors making their adaption unsuitable.
There is an unfulfilled need in the industry to provide compact energy efficient air cooling systems especially for use in off-road vehicles such tractors ideally be installable in existing vehicles without substantial modification of the vehicle cabin design that have to be operated under varying field conditions.

Object of the Invention
The main object of the invention is to provide energy efficient, easy to
install and use air-cooling systems without the use of mechanically or electrically
driven water circulating means.
Another object of the invention is to provide energy efficient, easy to
install and use air-cooling systems without the use of mechanically or electrically
driven water circulating means for off-road vehicle such as tractors.
Yet another object of the invention is to provide air-cooling systems with self irrigating cooling pads.
Another object of the invention is to provide a system obviating the use of water control system for irrigation of the pads in air cooling systems.
Yet another object of the invention is to provide self irrigating evaporative cooling system for cooling driver's cabin of tractor.
Another object of the invention is to provide self irrigating evaporative cooling system that is adaptable and installable in existing off-road vehicle without substantial modification of the driver cabin design.
Thus in accordance with the invention, the system comprises of
an air circulating means, water storage means adapted to remain in contact with
self irrigated evaporative pad;
wherein the said pad comprises of wicking material configured so as to produce
high rate of capillary effect to rise water to substantially wet the pad;
wherein
the said air circulating means that is disposed in front of the said pad induces air
through the said pad to cause evaporation of the water from the contacting
surface of the pad resulting in cooling air;

wherein
the said pad with the fast capillary action is so selected to ensure the wetting of
the pad during the air circulation;
inlet and outlet headers for air stream wherein the said headers are adapted to fit
on the said water storage means; optional louvers adapted to be fitted on the
outlet of air stream;
mounting means.
Description of the Invention
Features and advantages of this invention will become apparent in the following detailed description and the preferred embodiments with reference to the accompanying drawings.
Figure f Schematic of trie system (Sheet 1)
Figure 1 illustrates the system configuration. The system comprises of an air circulating means 4 disposed in front of the self irrigated evaporative pad 5 which is immersed in water storage means 1. The said means 4 induces air through the said pad 5. The said pad comprises of layers of wicking material (not shown) configured such as to produce high rate of capillary effect to rise water to wet entire portion of the pad. In one of the embodiment the said means 4 is disposed on the back side of the said pad so as to force air through the pad. Air direction is indicated by arrow 6. The water from the storage means 2 is raised (indicated by arrow 7) due to the capillary effect so as to wet th§ said pad. The contact of air with the surface of the irrigated pad causes evaporation of the water resulting in cooling the air. Inlet header 3 is adapted to fit on the said storage means 1. The outlet header portion 8 is adapted so as to provide conditioned air to the chamber / region to be cooled.
In one of the embodiments the said cooling pads are made of cellulose fibers configured in honeycomb structure. The inner layers are provided with wave structure which plays two important roles simultaneously .It absorbs the water and

keeps in the pockets of the cellulous paper and allows the air to pass through easily after evaporating the water and reducing the temperature of the air.
In one of the embodiments the air circulating means is a twin shaft axial type blower.
In another embodiment hand operated \ouvers are adapted to be fitted on the said outlet header portion 8.
Thus it is evident from the present invention that the synergistic combination of the self irrigating pad that uses wicking material to produce capillary effect so as to wet the pad along with the air circulating means and water storage means obviates the use of water pump to provide energy efficient, simple and easily mountable evaporative cooling system that is adaptable on existing off road vehicles. Further the low weight, compactness and adaptability for use with batteries, makes it amenable to being mobile for flexible use in any environment such as vehicles, offices, homes, etc.