Patent Application
20060096638
The present invention relates to a chemical delivery system for the condensate drain tray of air conditioners, which dispenses chemicals to inhibit microbial growth.
The condensation of water in air conditioning equipments requires the constant collection and disposal of water through drainage pipes or lines. The water standing still encourages the growth of microbials, such as algae, bacteria and other organisms that clog the pipes. Various designs for chemical delivery systems have been designed in the past.
U.S. Pat. No. 5,976,364 (to Williams) discloses an apparatus for treating air conditioner condensate with algicide. The apparatus provides dissolving biotic growth composition into air conditioner condensate fluid. The apparatus includes a housing for holding the inhibitor and a container, located within the housing. The container allows contact between the inhibitor and condensate while retaining undissolved inhibitor in the housing. Williams' device relies on moving parts, and it cannot use liquid chemicals, as they would be washed out with the condensate.
U.S. Pat. No. 6,651,690 B1 (to Coogle) discloses a chemical delivery system having an inlet and an outlet for connecting in the drain line downstream of the condensate drain tray to dispense chemicals into the drain line. This device is not used for connecting to the condensate drain tray to control microbial growth in the tray.
It is preferred to control microbial growth in the condensate drain tray, because it is the starting point of the condensate drainage system. Any growth in the tray can become the seed for growth in the downstream drain line. Currently, there are solid tablets available for placing into the condensate drain tray. However, direct contact of concentrate chemicals with the tray can be corrosive. Furthermore, one can not use liquid chemicals in the tray, because the chemicals will be washed out by the condensate water.
Therefore, there exists a need for chemical delivery system suitable for dispensing growth control chemicals, either liquid or solid, to the condensate drain tray.
In one embodiment, the present invention is directed to a chemical delivery system for an air conditioner, which comprises an elongated reservoir body having an open upper end, a closed lower end, and a central cavity; a tubular connector having a first end connected perpendicularly to the reservoir body, and connection means at a second open end for connecting to a drainage system of the air conditioner; the tubular connector being in fluid communication with the central cavity; a basket removably disposed within the central cavity; and a top cap removably connected to the open upper end of the reservoir body for closing the central cavity. The basket has an elongated basket body having an open upper end, a closed lower end, and a plurality of apertures disposed around a middle portion of the basket body for providing a fluid communication between inside and outside of the basket.
The upper portion of the reservoir body can have the same geometry and dimension as the other parts of the reservoir body. Alternatively, the upper portion of the reservoir body and the upper portion of the basket body can also have a funnel shape with enlarged openings for facilitating liquid dispense.
In a further embodiment, the chemical delivery system can have an open lower end and a bottom cap removably connected to the open lower end, which eases the cleaning of the reservoir body when desired. The chemical delivery system can further include a liquid level sensor in the tubular connector to sense potential damaging water level caused by drain line clogging.
It is noted that the like parts are labeled by the like numbers throughout the drawings.
In one embodiment, the present invention provides a chemical delivery system for controlling microbial growth inside condensate drain tray of an air conditioner and downstream thereof.
Referring now to
Basket 40 has an elongated basket body 42 which has an open upper end 44, a closed lower end 46, and a plurality of apertures 48 disposed around a middle portion 45 of elongated basket body 42. Preferably, middle portion 45 is more than one third of the total length of elongated basket body 42. Upon disposed within central cavity 26, the lower part of middle portion 45 extends vertically below tubular connector 30, and the upper part of middle portion 45 extends vertically above tubular connector 30, as shown in
As shown in
Preferably, the outer dimension of closed lower end 46 of basket 40 is complementary to the inner dimension of closed lower end 24 of reservoir body 20, to reduce the potential for debris accumulation in between. In the embodiment shown, closed lower ends 24 and 46 are semispherical. However, closed lower ends 24 and 46 can also have other suitable shapes and geometries. Optionally, basket 40 can further comprise a nipple 54 protruding from closed lower end 46, for preventing closed lower end 46 sticking on to the interior surface of closed lower end 24 by debris.
Furthermore, basket 40 can have retainer means 50 to maintain the vertical position of basket 40 within central cavity 26. In the embodiment shown in
The chemicals that can be placed in chemical delivery system 10 include liquid and solid forms of antimicrobials. Growth control tablets, such as Frost King Pan-Tablets manufactured by Thermwell Products, Co., Inc., New Jersey, can be conveniently dropped into basket 40. Any insoluble material from the tablet is accumulated inside basket 40, and can be easily cleaned as described above for cleaning the debris.
As shown in
Preferably, top cap 60 has a venting opening 62 as shown in
Chemical delivery system 10 can further include a liquid level sensor 70 disposed in the tubular connector for sensing water level increase caused by clogging of the drain line. Liquid level sensor 70 has a sensing portion disposed within tubular connector 30 between first end 32 and second end 34 and a connection portion 78 outside of tubular connector 30 for connecting to a control system. In the embodiment shown in
In an alternative embodiment as shown in
In a further embodiment as illustrated in
It is noted that the structure of the other parts of reservoir body 20b, tubular connector 30 and top cap 60 of chemical delivery system 80 are the same as those corresponding components of chemical delivery system 10 described previously.
In the embodiments shown in
Once chemical delivery system 10, 10a or 80, connects to the condensate drain tray, condensate water will enter into the chemical delivery system, and the water level will be in equilibrium between the condensate drain tray and the chemical delivery system. If the antimicrobial placed in the chemical delivery system is solid tablets, it dissolves gradually. The antimicrobial in the chemical delivery system will enter into condensate drain tray by diffusion, which can control the growth of microbials, particularly algae, in the tray and downstream drain line. Liquid chemicals function in the same way. Using the chemical delivery system of the present invention, one does not need to add concentrate chemicals directly into the condensate drain tray, which can be corrosive to the tray. Furthermore, the instant chemical delivery system also provides a time release mechanism for dispensing a small amount of antimicrobials for long term control and maintenance.
Reservoir bodies 20, 20a and 20b, tubular connector 30, baskets 40 and 40a, top cap 60 and bottom cap 90 are preferably injection molded of a plastic material, such as polyethylene, polyvinyl chloride (PVC), and polyamide.
It is noted that although chemical delivery systems 10, 10a, or 80 of the present invention are to be connected to the condensate drain tray for growth control inside the condensate drain tray, chemical delivery system 10 can also be connected to downstream air conditioner drainage system for preventing clogging of the drain line.
The invention has been described with reference to particularly preferred embodiments. It will be appreciated, however, that various changes can be made without departing from the spirit of the invention, and such changes are intended to fall within the scope of the appended claims. While the present invention has been described in detail and pictorially shown in the accompanying drawings, these should not be construed as limitations on the scope of the present invention, but rather as an exemplification of preferred embodiments thereof. It will be apparent, however, that various modifications and changes can be made within the spirit and the scope of this invention as described in the above specification and defined in the appended claims and their legal equivalents. All patents and other publications cited herein are expressly incorporated by reference.
