FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
& THE PATENS RULES, 2003
PROVISIONAL SPECIFICATION
[See section 10, Rule 13]
COOLING OR FREEZING DEVICES;


BLUE STAR LIMITED, A COMPANY
INCORPORATED UNDER
COMPANIES ACT 1956, WHOSE ADDRESS IS KASTURI BUILDINGS, MOHAN T. ADVANI CHOWK, JAMSHETJI TATA ROAD, MUMBAI-400 020 MAHARASTRA, INDIA;
THE FOLLOWING SPECIFICATION DESCRIBES THE INVENTION:

FIELD OF THE INVENTION
The present invention generally relates to cooling or freezing devices such as water coolers, chest freezers, chest coolers, chiller tanks, etc.
BACKGROUND ART OF THE INVENTION:
Generally, cooling/freezing devices such as water coolers, chest freezers, chest coolers, chiller, comprises a tank and a refrigeration system to cool/chill the said tank in order to cool or chill the contents in the said tank. The refrigeration system (Figure 1) in these devices generally includes a compressor, a condenser, the expansion device and an evaporator coil. These tanks are generally made of materials like pre painted galvanized Iron or Stainless Steel sheets. Referring Figure 2 and 3, the tanks (1) are wound with copper or aluminum or zinc coated mild steel tube (4) which is circular or semicircular in cross section. This coil serves as evaporator for these devices.
The evaporator coil is responsible for extraction of heat from the cooling cabinet/ tank. This tank (1) on which coil (4) is wound is further covered with insulation (5) to prevent cooling loss from evaporator coil (4) to the outside ambient. In this devices, the heat transfer from the content of tank (product to be cooled or frozen) to refrigerant is as follows:
a) Product to be cooled to tank wall
b) Tank wall to evaporator tube

c) Evaporator tube to refrigerant
In this process, the heat transfer is mainly due to conduction and natural convection. This heat transfer occurs due to the temperature difference between the tank contents and the refrigerant in the evaporator tube. The refrigerant absorbs the heat from the contents in the tank. Several factors are responsible for heat transfer between the refrigerant and the tank for a given length of evaporator tube. Those include th§ total internal surface area of the tube in contact with the refrigerant, turbulence in the flow of refrigerant, area of the evaporator tube in contact with the tank, the method of attaching the tube to the tank etc. Generally, coil used as evaporator has a circular, semiclrcufar or D-type cross section. Therefore, the contact of evaporator tube with the tank is only a line or small area for a given length of evaporator. Further, generally tube is soldered to the tank for improving the heat transfer efficiency from tube to tank. However, this process is expensive and complicated. Also, total surface exposed to the flowing refrigerant for a given length of evaporator and the turbulence in the refrigerant is less.
DESCRIPTION OF FIGURES
Figure 1 show a typical refrigeration circuit used in the cooling/freezing
devices such as water coolers, chest freezers, chest coolers, chiller tanks,
etc.
Figure 2 shows a prior art evaporator coil wound around the tank of the
cooling/freezing devices;
Figure 3 shows cross sectional view of the tank shown in Figure 2;

Figure 4 shows a multiple vein evaporator tube wound around the tank
according to the present invention;
Figure 5 shows cross sectional view of the tank shown in Figure 4.
DESCRIPTION OF THE INVENTION
An object of the present invention is to obviate the shortcomings of the prior art evaporator used in the cooling or freezing devices such as water coolers, chest freezers, chest coolers, chiller tanks, etc.
The present invention provides a cooling or freezing device comprising a tank for contents to be cooled or froze and a refrigeration system including a compressor, a condenser, the expansion and an evaporator coil for cooling/chilling the said tank in order to cool or chill the contents in the said tank wherein evaporator coil consists of multiple veins and manifolds are adapted at inlet and outlet of the evaporator coil for connection of the evaporator coil with the refrigeration system to increase the heat transfer between the tank and evaporator coil.
Referring to Figure 5 and 6, the tank (1) in the applications like water coolers chest freezers, chest coolers, chillers, etc. with the multiple vein evaporator tube (7) assembled in a foamed cabinet (2). Foam Insulation (5) is filled between the tank (1) and the outer body. The refrigeration system (3) includes a compressor (7), a condenser coil (8), an expansion device (9), evaporator coil or cooling coil (4). The condenser coil is cooled by natural convection in case of skin condenser or by the condenser fan (10) in case of forced convection.

According to the present invention, the cooling coil or evaporator coil is a
multiple vein tube (6) which is wound around the tank (1).
According to one embodiment of the present invention shown in Fig 5 and 6,
the evaporator tube (6) has an extended cross-section with multiple veins
(11). The tube has a rectangular cross-section which reduces the length of
the evaporator coil.
The multiple vein evaporator tube (6) can be wound on the tank (1) so that
the longer flat side faces the tank (1) surface to ensure the maximum surface
area in contact with the tank (1).
According to one of the embodiment of the present invention, the inside of
each vein (11) may be a square or circular or combination of any such
shapes. In addition to that, additional ribs/fins can be provided in the veins in
the inner side to create more turbulence to the refrigerant.
According to the present invention, the multiple vein evaporator tube (6) can
be retained by means of soldering or adhesion with appropriate conducting
adhesive so as to insure the maximum physical contact between the tank (1)
and the evaporator tube (6).
The multiple vein evaporator tube (6) is connected to the refrigerant circuit
(3) which consists of circular type cross sections with the help of manifold at
the inlet (12) and outlet (13). The manifolds can be soldered or joined at the
inlet and outlet sides. The manifold (13) from one side makes a place for
multiple vein evaporator tube and the other side for circular tube of the
refrigeration cycle.
The present invention provides effective area of the evaporator coil in
contact with the cooling tank for a given length of the evaporator tube.

Further, as the cross section being divided into multiple zones, the area in contact with the given amount of refrigerant is more and also increases turbulence resulting in the high amount of the heat transfer. Further, less amount of refrigerant is required for refrigeration. Because of better utilization of refrigerant liquid and improved efficiency of the system the power consumed by the system will be reduced. This further helps in reducing the scale of Global Warming Potential (GWP) and Ozone Depleting Potential (ODP). Dated this 22nd day of Januarv. 2009