Abstract:
The present invention is an improved AHU that can be easily architecturally disguised, made in a modular unit, have increased overall efficiency and ease of servicing, reduce radial noise emissions and allow for the direct adjacent placement of additional AHU&#39;s. This AHU has a cuboid structure with smooth side walls that are insulated and adapted for the attachment of aesthetic surface treatments, roof inset fans louvered end walls with door access. Heat removal can accomplished through angled heat exchangers also housed within the enclosure. Air filtration is also accomplished with angled filters. The improved aesthetic appearance of these units also eliminates the use of surrounding architectural parapet walls or screening units. The improved space effectiveness and modularity shall provide greater flexibility in building construction.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an architecturally advanced and more space efficient design for air handling units with or without an accompanying heat rejection unit. 
     Large capacity air handling units are a necessity for most large buildings whether residential, commercial or industrial in nature. These units being noisy, large and requiring a moderate amount of access space, are generally located on the rooftop, or on ground level, about the perimeter of the building. Herein lies part of the problem with the prior art. These packaged outdoor units are in visible locations yet form architectural eyesores. To remedy this situation, architects go to great lengths to make aesthetically appealing disguises. Walls, fences and flora are used to hide ground units whereas parapet wails and screening are used on roof units. 
     Where more than a single air handling unit (AHU) is required, additional units are generally located near rather than adjacent the first AHU because the prior art AHU&#39;s side airflow and side service requirements. 
     This new design of AHU is a modular style unit that has a compact footprint due to angled heat exchangers and filters, utilizes a floor/louvered end wall air intake and employs roof air exhaust, therein eliminating any unsightly appurtenances and allowing for the utilization of a smooth walled enclosure. This modular smooth walled enclosure is highly space efficient, and capable of being positioned directly adjacent to a substantially similar AHU. From an aesthetic standpoint the present design will have a cuboid configuration with smooth side walls allow for the attachment of architecturally appealing wall exterior surface treatments such as stucco, brick, tile, exterior wallboard or siding. The AHU also has a full length service corridor that doubles as an exhaust air pathway. 
     The heat rejection fans shall have vertical up discharge and shall serve multiple functions including operation as condenser fans, waste heat rejection fans, and a exhaust/relief air fans. The air handler shall be supported by a roof curb which shall fully enclose the supply and return ducting. Should the air handler be equipped with a condenser section, this portion of the unit will likely have open bottom to allow combination of louvered end wall and bottom air intake. With this design multiple units can be mounted side by side in adjacent configuration with only an increase in curb and pedestal height. This curb and pedestal height is required to offset the loss of air flow to competing AHU&#39;s. 
     Henceforth, an improved AHU unit would fulfill a long felt need in the building industry, especially in larger application that require multiple units and where space is at a premium. This new invention utilizes and combines known and new technologies in a unique and novel configuration to overcome the aforementioned problems and accomplish this. 
     SUMMARY OF THE INVENTION 
     The general purpose of the present invention, which will be described subsequently in greater detail, is to present an enhanced AHU that can be easily architecturally disguised, applied as a modular unit, increase overall efficiency and ease of servicing, reduce radial noise emissions and allow for the direct adjacent placement of additional AHU&#39;s. 
     It has many of the advantages mentioned heretofore and many novel features that result in a new AHU design which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof. In accordance with the invention, an object of the present invention is to provide an architecturally improved AHU design that does not have visible fans, compressors or heat transfer surfaces. 
     It is another object of this invention to provide an improved an improved AHU design that can be architecturally mated or configured to the building it is utilized with. It is a further object of this invention to provide an improved AHU that has minimal side accesses and protrusions. 
     It is a further object of this invention to reduce the level of noise radiated outward from the improved AHU. 
     It is still a further object of this invention to provide for an improved AHU that looks like a cuboid having the heat rejection heat transfer media and heat rejection fans usually serviceable from the unit&#39;s top. 
     It is yet a further object of this invention to provide an AHU that is assembled and shipped as few sections as possible and wherein multiple units can be mounted side by side in adjacent modular configuration. 
     The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. Other objects, features and aspects of the present invention are discussed in greater detail below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the exterior of a conventional AHU; 
         FIG. 2  is a perspective view of a conventional AHU disguised by an external architectural enclosure; 
         FIG. 3  is a perspective view of the improved AHU; 
         FIG. 4  is a perspective view of the improved AHU with an architecturally patterned façade designed to match it&#39;s building; 
         FIG. 5  is a perspective view of an improved AHU with a aesthetic brick façade; 
         FIG. 6  is a top cross section view of the improved AHU unit with cooled water or refrigerant used as a cooling medium; 
         FIG. 7  is side cross section view of the improved AHU with cooled water or refrigerant used as a cooling medium; 
         FIG. 8  is top cross section view of the second alternate embodiment AHU with a conventional air conditioning unit; 
         FIG. 9  is a side cross section view of the second alternate embodiment AHU with a conventional air conditioning unit; 
         FIG. 10  is a top cross section view of the first alternate embodiment AHU with a refrigerant based heat recovery system; 
         FIG. 11  is side cross section view of an the first alternate embodiment AHU with a refrigerant based heat recovery system; 
         FIG. 12  is top cross section view of the third alternate embodiment AHU with a full outside air supply and a heat pump; 
         FIG. 13  is a side cross section view of the third alternate embodiment AHU with a full outside air supply and a heat pump; 
         FIG. 14  is top view of the spacing of two conventional AHUs; and 
         FIG. 15  is a is top view of the spacing of three improved AHUs. 
     
    
    
     DETAILED DESCRIPTION 
     There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. 
     In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of descriptions and should not be regarded as limiting. An air handling unit (AHU) is the grouping of mechanical components into a single location, that condition and/or adjust the flow, pressure, temperature and humidity of a building&#39;s interior air. The AHU can have various mechanical and or refrigeration components and may accomplish its heating/cooling by utilizing various different methods including, but not limited to conventional refrigerant air conditioning, chilled water air conditioning and heat pumps. 
     Outside air is the eventual heat transfer media that the heat from the cooling system is rejected into, although this may be done in stages or through the use of other heat transfer media loops whether liquid or gas. The AHU is typically located outside the building, on the roof or on ground level. 
     Looking at  FIG. 1  and  FIG. 2  the conventional AHU  2  can be seen isolated and encased in an external architectural enclosure  4 . The conventional AHU  2  has a plethora of aesthetically unappealing appurtenances such as intake air rain hoods  6 , equipment enclosures  8 , exhaust air flow isolation hoods  10  and side louvers  12 . Hence, the need for the external architectural enclosure  4  to hide these unsightly structures. Not only to they look unappealing, they are dangerous to walk around, have increased overall footprints and cannot be adjacently located because of the appurtenances. Although not illustrated, these conventional AHUs are generally mounted about their lower periphery  13  directly onto similarly sized curbs on the rooftop to allow for the interconnection of building ducting, power and services. This complete periphery connection to the building necessitates the need for side air intakes/exhausts. 
       FIG. 3  shows a perspective view of an improved air handling unit (IAHU)  14  wherein it can be seen that the generally cuboid structure has smooth long side walls  16  of a planar, physically uninterrupted configuration such that there are no air vents, physical projections, or mechanical appurtenances therefrom. The proximate end wall is formed of a set flush louvers  30 . The distal end wall (not illustrated) has an access door, no appurtenances and either a smooth wall or a wall formed of a set flush louvers, depending upon the application. Only a lower base  18  of the IAHU forms a base and resides atop a rooftop curb. This lower base  18  serves as the interface between the building and the IAHU  14  through which service connections and ducting passes. The heat rejection end of the IAHU  20  (where the heat rejection occurs) contains the heat transfer media and heat rejection fans  25 , and resides on pedestal legs  22  although this section has no solid floor but rather a simple open frame so as to allow ambient, outside air, access up into the heat rejection end of the IAHU  20  or through the louver end wall  30 . This IAHU is a modular, contained package that can be easily shipped. The heat transfer media and flush mounted heat rejection fans  25  may be serviceable from the roof  27  of the IAHU. Each fan  25  can simply lifted out, unplugged and removed for service or replacement. Even the exhaust/relief air fans are serviced from the top or the service corridor. 
     With the smooth side wall  16  design, the IAHU  14  can have aesthetic surface adornments  24  applied that match or compliment the aesthetic surface adornments  26  of the building  28  they reside atop, as depicted in  FIG. 4 . In  FIG. 5  the surface adornment chosen resembles brick. 
       FIGS. 6 ,  8 ,  10 , and  12  are top cross sectional views taken through their respective embodiment of the IAHU as indicated by the sectional arrows B on their respective side cross sectional views shown on  FIGS. 7 ,  9 ,  11  and  13 . 
       FIGS. 7 ,  9 ,  11  and  13  are side cross sectional views taken through their respective embodiment of the IAHU as indicated by the sectional arrows A on their respective top cross sectional views shown on  FIGS. 6 ,  8 ,  10 , and  12 . 
       FIGS. 6 and 7  illustrate top cross sectional and side cross sectional views of the preferred embodiment IAHU  14  with cooled water or refrigerant utilized as cooling medium. This is the situation where the heat rejection from the air conditioning cycle occurs remotely. The structure can best be explained by detailing the air flow patterns. Here the outside air enters the IAHU  14  through the distal louvered end wall  34  as indicated by arrow  35  into the intake room  39  and a regulated flow passes through outside air damper  36 , as indicated by arrow  37  into plenum  38  where it mixes with building return air entering the IAHU though lower base  18  as indicated by arrow  19  and a regulated flow passes through return air damper  40  as indicated by arrow  41 . The resultant mixed air passes through slant filters  42  and slant cooling coils  44  as indicated by arrow  43 . The prime mover for both the building air and the outside air is the supply air fans  46  which reside in fan room  45  and which circulate the conditioned, supply air back down into the building through the lower base  18  as indicated by arrow  43 . A portion of the building return air passes through exhaust damper  56 , and traverses along access corridor  58  to heat rejection room  52  as indicated by direction arrow  60 . In this way the excess amount building exhaust air is mixed with the unwanted byproduct heat from fan motors  50 , electrical control panels  59  (mounted in the access corridor  58 ) and the reject heat from the air conditioning equipment  48  in heat rejection room  52  is exhausted via the roof through roof fans  25  in the direction indicated by arrow  61 . There is an access door  62  that allows entry into the IAHU&#39;s access corridor  58  from which access can be gained into the intake room  39 , plenum  38  and fan room  45  by any of the internal doors  71 . The proximate end wall  26  is not louvered. 
       FIGS. 8 and 9  illustrate top cross sectional and side cross sectional views of a first alternate embodiment IAHU  70  with a conventional refrigerant based air conditioning system wherein the refrigerant coils  66  are located inside the alternate embodiment IAHU  70 . Here it can be seen that the general outlay differs from the preferred embodiment IAHU  14  by the addition of a heat exchanger chamber  72  adjacent the heat rejection room  52  so as to house the slant heat exchangers  66  that remove the heat from the air conditioning system  48 . This heat exchanger chamber  72  resides held elevated relative to lower base  18  by pedestal legs  19  as does heat rejection room  52 . Here, it can be seen that additional rooftop fans  25  draw outside air into heat exchanger chamber  72  from louvered distal end wall  74  as well as up through the open floor and across slant heat exchangers  66  as indicated by indication arrows  75  and  76 . All other internal elements and flow patterns remain identical to the preferred embodiment IAHU  14 . 
       FIGS. 10 and 11  illustrate top cross sectional and side cross sectional views of an alternate embodiment IAHU  78  with a refrigerant based heat recovery system. Here it can be seen that additional slant filters  42  and slant cooling coils  44  have been added above the outside air damper  36  to allow additional cooling and filtration capacity of the air while not increasing the outside dimensions of the second embodiment IAHU  78  over those of the preferred embodiment IAHU  14 . The air conditioning components  48  reside over an extended lower base  18  and share a common heat rejection room  52  with the slant heat exchangers  66 . The floor  80  beneath the slant heat exchangers may be open to allow additional rooftop fans  25  draw outside air into heat rejection room  52  up through the open floor  80  and across slant heat exchangers  66  as indicated by indication arrows  82  and  84 . The proximate end wall  26  may be louvered. Note that depending upon the specific components installed in the AHU the floor may be open or closed. 
       FIGS. 12 and 13  illustrate top cross sectional and side cross sectional views of a third embodiment IAHU  86  with full outside air supply and a heat pump. This embodiment does not condition and return any of the building air but rather continually intakes fresh air (as indicated by direction arrow  90 ) and conditions it through slant filters  42  and slant cooling coils  44  for cycling through the building (as indicated by direction arrow  92 ) and then out of the building as exhaust air via heat rejection room  52  and roof fans  25  as indicated by direction arrows  94  and  96 . As such, this embodiment does not have a plenum  38  but rather just an intake room  39 . Again the prime mover is supply air fans  46  which reside in fan room  45  and draw the outside air through the distal louvered end wall  34  and pushes it, once conditioned, into the building through ducting in the lower unit  18 . The floor  80  beneath the slant heat exchangers  66  maybe open to the rooftop fans  25  to draw outside air into heat rejection room  52  up through the open floor  80  and across slant heat exchangers  66  as well as draw the building exhaust air up through exhaust duct  100  and into heat rejection room  52  for eventual exhaust to atmosphere. 
       FIG. 14  shows the acceptable placement of two conventional AHUs  2 . Note, that these cannot be located adjacent one another because of the interference with the side wall appurtenances such as air rain hoods  6 , equipment enclosures  8 , exhaust air equipment enclosures  8 , and because they exhaust and intake significant quantities of air through their air rain hoods  6 , and exhaust air flow isolation hoods  10 . The IAHU  14  can be mounted directly adjacent a substantially similar unit because of the smooth long wall design and their modularity. 
     Note, that all embodiments of the invention utilizes slant filters  42 , slant cooling coils  44  and slant heat exchangers  66  as this design allows a more efficient heat transfer and particle entrapment than their conventional counterparts. The slant cooling coils  42  and slant heat exchangers  66  are of the conventional tube and fin design which is well known by one skilled in the art. By residing at an angle in the IAHUs, and by virtue of their oblique prismatic construction, more tubes can be used, more plate thermal conductive surface area can incorporated onto the coil, a larger coil face area can be realized, and more filter media can be used in the filter. When residing in the IAHUs at angles less than 90 degrees, there is a significant increase in coil heat transfer area and particulate entrapment area. More importantly, the face velocity and resultant air friction of the passing air decrease significantly, thereby reducing the amount of work the prime mover exhaust/relief air fans  46  have to do. While this slant design requires more linear space than single, normally situated conventional elements do, when multiple units are stacked a significant increase in efficiency can be realized with a decrease in spacial utilization. 
     Although depicted in four embodiments, the novel features of the present invention are common to all embodiments and include smooth solid exterior walls adapted for the attachment of aesthetic surface treatments and to reduce the sound level of radial emitted noise, an elevated heat rejection room with an open bottom floor adapted to allow under floor routing of refrigerant/fluid piping and/or electrical conduit as well as location for wet wells, fans adapted for topside accessibility, slant filters and slant cooling/heat rejection coils, isolated byproduct heat removal capability and end access doors leading into access corridors that serve as exhaust air ducts and locations for the mounting of unwanted heat byproduct generating equipment and from which the intake room, plenum and fan room can be accessed, such that the IAHU is adapted to allow the side by side placement of two or more units without sacrificing heat rejection efficiency. Access to heat rejection heat exchangers may be from top or via removable panels. The improved aesthetic appearance of these units eliminates the use of surrounding architectural parapet walls or screening units. 
     The above description will enable any person skilled in the art to make and use this invention. It also sets forth the best modes for carrying out this invention. Those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention now that the general principles of the present invention have been disclosed. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.