Patent Abstract:
A duct system has at least one duct for communicating air or fluid within a building and a plurality of openings along the top of the duct along the central axis. An ingress pipe is coupled to the openings along the top of the duct along the central axis, A plurality of openings are also provided along the bottom of the duct along the central axis of the duct. A drain pipe is coupled to the opening along the bottom of the duct along the central axis, where a user may inject a fluid into the duct using the ingress pipe and where the fluid is drained and collected from the duct using the drain

Full Description:
RELATED APPLICATION 
       [0001]    This application claims the benefit of priority from U.S. patent application Ser. No. 11/890,764, filed on Aug. 7, 2007, the entirety of which is incorporated by reference, 
     
    
     BACKGROUND 
       [0002]    1. Field of Invention 
         [0003]    The present invention is in the field of ducts. More particularly, the present invention is in the field of ducts with improved cleaning capabilities. 
         [0004]    2. Background 
         [0005]    Ducts provide transport passageways for a wide variety of applications, For example, ducts provide passageways for transporting gases for heating and ventilation in vehicles and buildings. Likewise, water distribution systems often use ducts for fluid transport. Ducts for the foregoing and other applications can be formed of metal, plastics, ceramics, composites, and other materials. 
         [0006]    In HVAC (Heat Ventilation and Air Conditioning) systems, air passes through enclosed channels referred to as air ducts that communicate supply air from a central air handler via a centrifugal fan or blower to the various rooms of the building. Other ducts communicate return air from the rooms back to the central air handler for filtering, cooling, heating, and so forth. The supply air and even more so the return air ultimately contains dust, debris, and microbial contaminates, Gradually over time, some of these particulates accumulate on the interior walls of the air ducts. Excessive accumulation of these particulates degrades the performance of the air duct system by impeding necessary air flow. Similarly, significant portions of these contaminants can be redistributed to the air supply. Regular cleaning and maintenance activities eliminate a portion of the contaminants. Routinely changing the filters in an HVAC system will help remove air borne particles, but only to the degree that the filter is rated and only until the filter becomes loaded with debris. 
         [0007]    The return duct is the dirtiest and most germ filled duct in air duct systems. All dirt gets stuck in the bottom, sides, and top of the duct. When some of the particles finally reach the filter, then they get trapped in the filter. The benefit of cleaning out the duct system that by washing and decontaminating the ducts, germs, dustmites and other harmful bacteria are flushed out. In addition, when there is a good filter the heat and air conditioning system can perform better, reducing energy costs. There are some filters claiming that they can dean the air up to 99.9%, provided that the user maintains it, however, such claims belie the fact that the ducts remain full of contaminants without regular thorough cleanings. 
       OBJECTS AND SUMMARY 
       [0008]    A main objective of this system is to disinfect the germs and bacteria that develop in duct systems, or in systems that just cannot be maintained properly. 
         [0009]    The present system provides a novel duct system with integrated nozzles for ingress and egress of washing fluids that reduces and/or eliminates the need for the time consuming process of manually cleaning the ducts. 
         [0010]    To this end, the present invention provides for a duct system having at least one duct for communicating air or fluid within a building and a plurality of openings along the top of the duct along the central axis. An ingress pipe is coupled to the openings along the top of the duct along the central axis. A plurality of openings are also provided along the bottom of the duct along the central axis of the duct 
         [0011]    A drain pipe is coupled to the opening along the bottom of the duct along the central axis, where a user may inject a fluid into the duct using the ingress pipe and where the fluid is drained and collected from the duct using the drain pipe. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is an underside view of a duct system in accordance with one embodiment; 
           [0013]      FIG. 2  is an illustration of an intake coupler according to one embodiment; 
           [0014]      FIG. 3  is an underside view of a drain line on the duct of  FIG. 1  in accordance with one embodiment of the present invention. 
           [0015]      FIG. 4  is a top view of the duct system of  FIG. 1  in accordance with one embodiment; 
           [0016]      FIG. 5  is a top view of the duct of  FIG. 1 , in accordance with one embodiment; 
           [0017]      FIG. 6A  is an illustration of a nozzle inserted into a duct of  FIG. 1  in accordance with one embodiment; 
           [0018]      FIG. 6B  is an illustration of a multiple tube ingress pipe with the duct of  FIG. 1 , in accordance with one embodiment; 
           [0019]      FIG. 7  is an illustration of a duct system control panel in accordance with one embodiment; and 
           [0020]      FIG. 8  illustrates a duct system with separate zones, in accordance with one embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    In one embodiment, a duct system  10  is shown in  FIG. 1  according to the present invention. This duct system employs features for allowing self-cleaning and draining of the cleaning fluid without the need for mechanical scrubbing. For the purposes of illustrating the salient features of the present invention, a simple cross-duct intersection is shown. However, it is understood that modifications and expansions may be employed along an entire duct system, such as those typically employed in a commercial or residential structure. 
         [0022]      FIG. 1  illustrates an HVAC return duct system  10  from the underside showing an HVAC Unit  12  attached to a round central duct  14 , A round side duct  16  intersects with round central duct  14 . Air intake ports  18  extend from round side duct  16  and central duct  14  at various locations. 
         [0023]    Duct system  10  and its component parts are preferably dimensioned according to industry standards and to accommodate the required air flow (CFM) for the systems they support, For example, a typical HVAC unit may require duct system  10  to handle 1200CFM such that central and side ducts  14  and  16  are dimensioned to between 10″ and 20″ in diameter, It is noted that the system, although shown with round ducts may be equally employed with square or rectangular ducts as well. 
         [0024]      FIG. 2  shows an additional intake coupler  20  which connects a round intake port  18  to the typically square vents in the wall of the building. The top of intake coupler  20  is flat and the sides are pitched, so that water will drain back into the duct for removal if any collects outside of ducts  14  and  16 . The length of intake coupler  20  is preferably 12 inches but other dimensions may be employed. The connection between intake coupler  20  and round intake port  18  may be flanged, gasketed, and screwed together so as to prevent unwanted water leakage. 
         [0025]    Returning to  FIG. 1 , a series of drain openings  22  are illustrated, located along central axis of ducts  14  and  16 . Drain openings  22  are connected by a drain pipe  24  that is attached to/built into ducts  14  and  16 . Drain pipe  24  leads to a central waste pipe  26  which is connected to check valve  28 . Piping  24  and  26  may be made from any desirable piping material including but not limited to PVC, metal and rubber/polymer; and braided (non-burst) flexible lines, It is understood that drain openings  22 , pipe  24  and waste pipe  26  are all dimensioned according to the desired liquid flow and pressure that is used, as described in more detail below. 
         [0026]      FIG. 3  depicts a close up of drain openings  22  with an attached drain coupling unit  29  which connects opening  22  with drain pipe  24 . 
         [0027]      FIG. 4  is a top view of duct system  10  from  FIG. 1 . There are inlet openings  50  along the top central axis of ducts  14  and  16 . Inlet openings  50  are connected by ingress piping  52 . Ingress piping  52  is connected to both a water supply system  60  and a cleaner system  70 . 
         [0028]    Water supply system  60  is connected to a main water supply pipe  62 , a back flow preventer (Le, one way valve)  64 , a filter  66 , a solenoid  68  (main on/off switch) and check valve  69 . Backflow preventer  64  prevents chemicals from entering the drinking water if such systems use the same main water supply pipe  62 . 
         [0029]    Cleaner system  70  has cleaner reservoir  72  which contains chemical disinfectants or other such cleaners, a pump  74  and solenoid  76 . It is understood that the present invention, may operate with a water only arrangement (not shown) or with both water system  60  and cleaner system  70 . It is noted that water supply system  60  and cleaner system  70  may each alone, or combined by coupled to an additional pumping system for extra pressurization during the below decribed cleaning process. 
         [0030]      FIG. 5  shows an up close top view of ducts  14  and  16 . Nozzle  80  may be constructed as a multidirectional nozzle for an easy and effective spray around the entire nearby surface of the duct  14 / 16 . A t-connector  82  connects ingress piping  52  to nozzle  80  through opening  50  in the duct  14 / 16 . 
         [0031]    In one embodiment, nozzle  80  may be constructed as any one of a rotating head, fixed pattern heads, spinning heads, multi functional heads, computer managed heads, moisture sensing heads, multi pattern heads, fixed heads, removable heads, different size (volume) heads, electrostatic heads which electrically remove dust particles, As with the piping in system  10 , nozzle  80  is dimensioned according to the desired flow rate and pressures required by water supply system  60  and cleaner system  70 . 
         [0032]    Nozzles can also be installed in the HVAC  12  cooling coil to keep the coil clean automatically and keep the water that builds up on the drain pan clean and free of any bacteria or legionaries disease. 
         [0033]    In another embodiment of the present invention,  FIGS. 6A  illustrates a multi purposes nozzle inserted into the duct system. T connect or  102  is attached through the upper opening  50  of duct  14 / 16 . A dual mode nozzle  104  maintains two sprayers  106  and  108  with sprayer  106  being a chemical sprayer  106  and bottom sprayer  108  being a wash/ water sprayer  108 .  FIG. 6B  depicts an alternative ingress piping  110  having both a water channel  112  coupled to water sprayer  108  and a chemical channel  114  attached to chemical sprayer  106 . 
         [0034]    In another arrangement, above described nozzles, such as nozzles  80  may be included not only in duct system  10  but up to and including the HVAC unit  12 , and in particular the cooling cons, such that the below described cleaning cycles may additional dean components of the HVAc that are in contact with airborne pollutants. Such nozzles  80  may further include a rotating head (powered externally or internally from fluid flow pressure) to ensure full coverage of the coils. 
         [0035]    It is understood that the connections between the nozzles and ducts in system  10  may be either fixed or replaceable, allowing nozzle changes for different applications or maintenance on broken or dirty nozzles. 
         [0036]    Regarding all above connection in duct system  10 , it is contemplated that all connections between duct/nozzle/drain components are water tight, which may be arranged through any manner of water tight arrangements including but not limited to physical pressure sealed gaskets, permanent water proof cement/epoxy, water tight caulking/sealants etc . . . 
         [0037]    In one embodiment as portrayed in  FIG. 7  that both embodiments would use a control panel  200  which is connected to main water supply  60  and cleaner system  70 . The control panel contains of a power source  202  and a processor  204  for operating the pumps and solenoids. Processor  204  may employ calendar module  206 , timer wash module  208 , timer chemical module  210 , chemical dispenser (volume) module  212 , wash cycle module  214 , and over ride switch  216 . The various modules may be used for scheduling and executing cleaning cycles using the above described components. Override switch may be a manual switch or may alternatively/jointly be coupled directly to check valve  69 . An optional touch screen display may be employed for a user interface. 
         [0038]    In operation, upon a scheduled cleaning, water and/or chemicals are sprayed into the ducts via ingress piping  52  and nozzles  80  from water and cleaning systems  60  and  70 . After the requisite amount of fluid is dispensed and an appropriate wait time elapses, the water is collected via exit openings  22  and drain piping  24  to the main waste collection tank  26 . In one arrangement an added blower system may be used to energize the solenoids  68  and  76  so that the water from system  60  starts flowing and may be later used for drying once the wash cycles are complete. 
         [0039]    In one arrangement, the first wash through of ducts  14  and  16  is with the chemicals from system  70 . Then, system  10  may be washed again to dean all water lines ( 52 ) and nozzles  80  in order to prevent dogging. 
         [0040]    In an exemplary wash cycle implemented by control panel  200  and duct system  10  a first water rinse may be scheduled for a 1 minute rinse. Next a 3 minute water/cleaner cycle may be employed for washing the system, followed by a 3 minute water only rinsing. 
         [0041]    It is understood that durations of such washing/rinsing cycles may be adjusted along a wide range of times, and scheduled for daily, weekly, monthly etc . . . cleanings. Such wash cycles are completely programmable through control system  200  with optional manual changes or overrides if necessary. 
         [0042]    In another embodiment, as illustrated in  FIG. 8 , duct system  10 , when being employed in larger installations, may employ a zone system whereby portions of system  10  are subdivided into smaller zones to ensure complete coverage. 
         [0043]    For example, as shown in  FIG. 8  duct system  10  maintains five zones  300 ,  302 ,  304 ,  306  and  308 . Within each zone, ducts  14  and  16  and their associated ingress piping  52  are coupled to water supply system  60  and cleaner system  70 . 
         [0044]    In a first option a single water supply system  60  may be employed with step-up pumps  310  for each zone  300 - 308  or alternatively, (not shown) individual water supply systems  60  can be employed for each zone. Control panel  200  as described above may be utilized in a similar manner controlling the cleaning/rinsing schedules for each zone. 
         [0045]    Such an arrangement is advantageous when long sections of ducts  14  and  16  may result in poor coverage of cleaner and water in areas near the ends of ingress piping  52 . The present arrangement remedies such a situation and prevents the need for very high pressure to reach the ends of system  10 . 
         [0046]    System  10  may be employed in all indoor and outdoor heating and HVAC systems, including rooftop HVAC applications. Other applications for plastic ductwork with adaptable nozzle parts could be used to purge aft through nozzle systems for various reasons with fragrances of different scents, 
         [0047]    In an alternative embodiment, system  10  may be retrofitted with any tight fitting duct system. For example, in an existing watertight duct system, a hole may be drilled into the upper section of the duct to allow for a water nozzle to be inserted. A drainage opening can be made in the duct oppose the water nozzle to allow for removal of the cleaning fluid. 
         [0048]    While only certain features of the invention have been illustrated and described herein, many modifications, substitutions, changes or equivalents will now occur to those skilled in the art. It is therefore, to be understood that this application is intended to cover all such modifications and changes that fall within the true spirit of the invention,

Technology Classification (CPC): 5