Patent Application
20250092648
The present invention relates to the field of household appliances and specifically to a domestic water cooler designed for, but not limited to, houses in hot regions where municipality water is stored in rooftop tanks. In hot regions, the water stored in rooftop tanks can become excessively hot, making it uncomfortable for bathing or washing. The high water temperature is due to several reasons including high ambient temperature, direct sunlight and hot water supply from the source. Traditional methods of cooling, such as refrigeration or ice, may not be practical or cost-effective for cooling large quantities of water. One of the popular means is to leave tank uncovered or install exhaust fan on tank cover to circulate air to cool the water down. Those methods proven effective in cooling; however, they will contaminate the water inside the tank and vaporize disinfectant chlorine.
Evaporative cooling has been described in prior art patents. For example, U.S. Pat. No. 7,234,309 discloses dividing the cooling fluid, which has been evaporatively cooled by outside air as it passed through an evaporative cooling section, into a first cooling fluid and a second cooling fluid, and re-circulating the first cooling fluid in an apparatus to be cooled. U.S. Pat. No. 10,712,031 describes a system comprising an evaporative cooling water source, a water-to-water heat exchanger in fluid communication with the evaporative water source, an air-to-water heat exchanger in fluid communication with the water-to-water heat exchanger and positioned to received heated air from a group of electronic devices.
However, evaporative cooling has not been effectively applied to water storage devices for home use. There is a need for an economical domestic water cooler specifically designed for houses in hot regions, which can effectively cool the stored water without the need for refrigeration or additional energy consumption.
The present invention provides a device to cool the water supplied from the hot source (rooftop tank or municipality water supply network) and supply relatively cold water for household use. This invention is to avoid the mix of the contaminated water used for evaporative cooling and the fresh water supplied to the house.
According to an aspect of the present invention, there is provided a tank inside the main tank with the inner tank water open to the outside air/wind and cooled by natural evaporative cooling. The cold water in the inner tank then cools the fresh water in the outer main tank by conduction heat transfer. The design ensures that the inner tank contaminated water does not mix with the fresh water in the outer main tank. The device presented here in three embodiments, all based on the same concept, which cover a standalone cooling tank, a retrofit to an existing tank and a dual-purpose tank for water storage and cooling.
This invention described in three embodiments, namely, standalone cooling tank, retrofit to existing tank and dual-purpose tank for water storage and cooling. They all based on the same concept.
This embodiment is a dedicated cooling tank which comprises of a sealed tank 1 shaped to integrate inner tank 2 and outer tank 3 in one piece with outside thermal insulation 4. The water in the inner tank 2 is exposed to the outside air, which will cool the water in the inner tank 2 by evaporative cooling. The cold water in the inner tank 2 in turn cools the fresh water in the outer sealed tank 3 by heat conduction. The water in inner tank 2 will be topped up as needed through a float valve 5 with shut off valve 6 for cleaning and maintenance, allowing water to enter from the outer tank 3 without return flow.
The outer tank 3 is equipped with inlet 7 from a slightly higher head pressure such as from a taller or higher tank. This inlet directs the water flow upward where the hotter water is, while the exit port 8 tends to take the water from the bottom colder water.
The tank can also be equipped with air vent valve 9 to provide relief for trapped air if any. It can also be equipped with a well-vented cover 10 for shade and free air/wind circulation. The cover also prevents birds and animals from entering. The cover 10 can include a fan 11 of any type to enhance cooling if needed, fan not shown.
The inner tank also has a drain 12 with a screen and plug for periodical cleaning.
The function is as follows. Fresh water enters the inlet 7 from a taller or higher tank or directly from municipality supply. Hot water will fill the outer tank 3 and then will fill the inner tank 2 through the float valve 5 to the set level. The water in the inner tank 2 will evaporate and cool and in turn will cool the water in the outer tank 3 by heat conduction. The thermal insulation 4 avoids reheating from outside ambient temperature. Relatively cold water is supplied to the house through exit port 8.
This embodiment offers a retrofit solution for existing tanks using the same concept of evaporative cooling. A separate tank 14 designed to fit into an existing tank 13 through the cover opening, extending well below the full water level. This tank 14 is equipped with a low-pressure one-way valve 15, shown in
It is important to thermally insulate the outer tank 13 (insulation not shown) to avoid reheating from the sun or the high ambient temperature.
A third embodiment is a specially made dual-purpose tank for water storage with cooling feature, as shown in
The outer tank is thermally insulated (not shown) to avoid reheating from the sun or the high ambient temperature.
All embodiments of the water cooler provide an efficient and cost-effective solution for cooling stored water. The design allows for easy installation and maintenance, ensuring a constant supply of relatively cold water for household use. Other embodiments could also be adapted for commercial and industrial use.
Having thus described a few particular embodiments of the invention, various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this description though not expressly stated herein, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only of several of many potential embodiments, and not limiting. The claims are not intended to import any limitations from the description in the specification of the exemplary embodiments.
In particular, the schematics of the embodiments described could be altered such that inner tank and outer tank could be reversed, the tanks could be side-by-side, above and below, or positioned in any number of configurations while still falling within the core concept of evaporative cooling described herein.
