FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION
(See section 10 and rule 13)
TITLE OF THE INVENTION
«
An enclosure for a storage water heater tank
APPLICANTS
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai - 400 030, Maharashtra, India, an Indian Company
INVENTORS
Sathe Mahesh Kashinath and Katti Sudarshan of IDC, Global R&D Centre, Crompton Greaves Limited, Kanjur (E), Mumbai- 400042, Maharashtra, India, both Indian Nationals.
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the nature of this invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
This invention relates to a storage water heater.
BACKGROUND OF THE INVENTION
Storage water heaters running on electricity operate to provide the full load of heated water to the user. The water heating tank in a storage water heater is usually enclosed within pre-casted front and a back enclosure made up of Acrylonitrile Butadiene Styrene (ABS plastic) and is provided support with the enclosures by means of metallic brackets. The space between the enclosures and the water tank is filled with polyurethane foam which acts as an insulating medium to reduce convectional heat losses. The joint between front and back enclosures is fortified by some bolts running perpendicularly between the enclosures. In spite of the insulation provided, over a period of usage the pre-casted enclosures tend to get deformed/bulged due to the inherent lateral forces involved in the heat expansion of the enclosures. Such a deformation results in the aesthetic damage and can also cause an electric hazard in case of a water leakage from the water tank. There is a need for providing an enclosure to a water heater tank which can resist deformation over a long period of usage.
OBJECTS OF THE INVENTION
An object of the invention is to provide an enclosure to a storage water heater tank.
Several aspects of the invention are described below with reference to examples for illustration. It should be understood that numerous specific details, relationships, and

methods are set forth to provide a full understanding of the invention. One skilled in the relevant art, however, will readily recognize that the invention can be practiced without one or more of the specific details, or with other methods, etc. In other instances, well known structures or operations are not shown in detail to avoid obscuring the features of the invention.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention a storage tank-type water heater enclosure is provided which comprises of a set of pre-casted front and back enclosures defining an interior space for receiving a water storage tank. The joint between the front and back enclosure is tightened with bolts running across in an inclined manner covering a large surface area formed by the enclosures. The front enclosure is cast-molded in a manner such as to provide a plurality of screw threaded bosses in which the bolts are screwed to provide a tight support between the enclosures.
The following is a detailed description of the invention with reference to the accompanying drawing, in which:
Figure 1 is an isometric cut section view of a storage water heater along the bolting plane in prior art.
Figure 2 is a top cut section view of a storage water heater along the bolting plane in prior art.

Figure 3 is an isometric cut section view of a storage water heater along the bolting plane according to an embodiment of the invention.
Figure 4 is a top cut section view of a storage water heater along the bolting plane according to an embodiment of the invention.
In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements.
Figure 1 is an isometric cut section view of a storage water heater along the bolting plane in prior art. Figure 1 is shown containing the front enclosure 1, back enclosure 2 and the bolt 3. As can be seen the bolt support both the front enclosure and back enclosure perpendicular to the vertical central axis of the water heater.
Figure 2 is a top cut section view of a storage water heater along the bolting plane in prior art. Figure 2 additionally illustrates the tank 4 as supported between front enclosure 1 and back enclosure 2 by means of metal bracket 6. The area between the enclosures and the tank is usually filled up with insulating material like polyurethane foam. The back enclosure 2 has wall mounting means 6 and can be fitted on to a side wall.
As may be appreciated by one skilled in the relevant arts, the enclosures have a tendency to bulge along the line of contact/joint because of the lateral forces caused by heat expansion.

Figure 3 is an isometric cut section view of a storage water heater along the bolting plane according to an embodiment of the invention. Compared to Figure 1, it can be noticed that the bolt 3 is running at an inclination and ensures a firm support between the front enclosure 1 and back enclosure 2. Screw threaded bosses 7 are provided in the front enclosure 1, in to which the bolt 3 can be screwed in.
Figure 4 is a top cut section view of a storage water heater along the bolting plane according to an embodiment of the invention. Figure 4 illustrates the manner in which the tank 4 is supported between the front enclosure 1 and back enclosure 2. Figure 4 clearly shows how the bolts 3 running across the surface area at an inclination. The bolts 3 when provided with inclination causes a greater lateral force component to get exerted and restrict deformation to the enclosures caused by the heat expansion.

We claim:
1. A storage tank-type water heater enclosure, comprising:
a set of pre-casted front and back enclosures defining an interior space for receiving a water storage tank, wherein the joint between the front and back enclosure is tightened with a plurality of bolts running across in an inclined manner covering a large surface area formed by the enclosures, wherein the front enclosure is cast-molded in a manner such as to provide a plurality of screw threaded bosses in which the plurality of bolts are screwed to provide a tight support between the enclosures.
2. A storage tank-type water heater enclosure as claimed in 1, wherein the angle of inclination formed by the plurality of bolts with the vertical central axis formed by the enclosures is between 20 and 40 degrees.
3. A storage tank-type water heater enclosure as claimed in 1, wherein the back enclosure is wall-mountable.