Abstract:
A cabinet comprising an access panel having a first end and a first tongue formed proximate the first access panel end, and a top panel having a first end with a first slot formed therein; wherein the first tongue is configured to cooperate with the first slot to fasten the top panel to the access panel. In one embodiment, the cabinet may be a heating, ventilation and air conditioning (HVAC) system cabinet. A method of manufacturing the cabinet is also provided.

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    The present invention is directed, in general, to equipment cabinetry and, more particularly, to a cabinet for HVAC applications such as air filters, photocatalytic oxidation (PCO), and electronic air cleaners (EAC). 
       BACKGROUND OF THE INVENTION 
       [0002]    Heating, ventilating and air conditioning (HVAC) systems require ducting to route conditioned air to the served area and return air back to the HVAC equipment for further conditioning. These ducts may be rigid and constructed of sheet metal or flexible and constructed of a variety of materials including several plastics. Among the conditioning processes performed on return air is filtration, photocatalytic oxidation (PCO), and electronic air cleaner (EAC). Typically, these processes are done in sequential stages to the air and therefore require some form of cabinet to house the equipment that performs the process while the return air passes through the cabinet. Historically, these cabinets have been constructed of sheet metal and may be shipped from the manufacturing plant to the sales or installation site in assembled form. Especially in the case of the filter cabinet, this results in a bulky, but light-weight cabinet, because the filters are generally packaged separately. The filter cabinet is fully assembled and only needs to be installed in the return air duct and a filter inserted. This traditional approach may result in higher shipping costs as well as requiring more storage space because of the size. 
         [0003]    Accordingly, what is needed in the art is a filter cabinet that can be stored and shipped in a knocked-down state, thereby saving storage and shipping bulk, but that is readily assembled at the installation site and of sufficient strength to be functional for many years. 
       SUMMARY OF THE INVENTION 
       [0004]    To address the above-discussed deficiencies of the prior art, the present invention provides, in one aspect, a cabinet comprising an access panel having a first end and a first tongue formed proximate the first access panel end, and a top panel having a first end with a first slot formed therein; wherein the first tongue is configured to cooperate with the first slot to fasten the top panel to the access panel. In one embodiment, the cabinet may be a heating, ventilation and air conditioning (HVAC) system cabinet. A method of manufacturing the cabinet is also provided. 
         [0005]    The foregoing has outlined preferred and alternative features of the present invention so that those skilled in the pertinent art may better understand the detailed description of the invention that follows. Additional features of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the pertinent art should appreciate that they can readily use the disclosed conception and specific embodiment as a basis for designing or modifying other structures for carrying out the same purposes of the present invention. Those skilled in the pertinent art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    For a more complete understanding of the invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which: 
           [0007]      FIG. 1  illustrates an exploded isometric view of one embodiment of an equipment cabinet constructed according to the principles of the present invention; 
           [0008]      FIG. 2A  illustrates an exploded, close up vertical sectional view of the first top panel end and the first access panel end along line  2 - 2  of  FIG. 1 ; 
           [0009]      FIG. 2B  illustrates a close up vertical sectional view of the first top panel end coupled to the first access panel end along line  2 - 2  of  FIG. 1 ; 
           [0010]      FIG. 3  illustrates an isometric view of the cabinet of  FIG. 1  as assembled with the door panel installed; 
           [0011]      FIG. 4  illustrates an exploded isometric view of a second embodiment of an equipment cabinet constructed according to the principles of the present invention; 
           [0012]      FIG. 5  illustrates an isometric view of the cabinet of  FIG. 4  as assembled with the door panel installed; and 
           [0013]      FIG. 6  illustrates an exploded isometric view of another alternative embodiment of a cabinet constructed according to the principles of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Referring initially to  FIG. 1 , illustrated is an exploded isometric view of one embodiment of an equipment cabinet  100  constructed according to the principles of the present invention. In one embodiment, the equipment cabinet may be a heating, ventilation, and air conditioning (HVAC) system filter cabinet. While this description will discuss the application of the present invention to an air filter cabinet, one who is skilled in the art will recognize that the cabinet construction and assembly may also be used for other HVAC processes such as: photocatalytic oxidation (PCO), and electronic air cleaner (EAC). Of course, the cabinet construction as detailed below may also be applicable to cabinets other than HVAC. 
         [0015]    The equipment cabinet  100  comprises an access panel  110 , a top panel  120 , a back panel  130 , a bottom panel  140  and a cover panel  150 . The access panel  110  comprises a first end  111 , a second end  112 , an access opening  113  therethrough, a first outer flange  114   a , a first inner flange  114   b , a second outer flange  115   a  (not visible), a second inner flange  115   b , a plurality of locking nibs  116  formed in the first inner flange  114   b , a plurality of female fasteners  117 , and an outer side flange  118 . In a preferred embodiment, the access opening  113  allows service access to the equipment within the cabinet once the cover panel  150  is removed. A single locking nib  116   a , i.e., a projection of material above or below the surface in which it is located, is also formed at each corner of the outer side flange  118 . In the illustrated embodiment, the first inner flange  114   b  is configured as a first tongue  114   b . The first tongue  114   b  and the outer side flange  118  are substantially normal a face  119  of the access panel  110 . 
         [0016]    The top panel  120  comprises a first end  121 , a second end  122 , a first slot  123  formed in the first end  121 , a second tongue  124  formed at the second end  122 , a top edge panel  125 , a plurality of locking apertures  126  formed in the first end  121  at the first slot  123 , and a plurality of locking nibs  127  formed in the second tongue  124 . The second tongue  124  and the top edge panel  125  are substantially normal a face  128  of the top panel  120 . The back panel  130  and bottom panel  140  are configured in a like manner as the top panel  120  having first and second ends  131 ,  132  and  141 ,  142 , respectively. The first and second back panel ends  131 ,  132  comprise third and fourth slots  133 ,  134 , respectively. The bottom panel first end  141  has a third tongue  143  and the bottom panel second end  142  has a fourth slot  144 . The cover panel  150  comprises a plurality of male fasteners  151  configured to cooperate with the plurality of female fasteners  117  to removeably couple the cover panel  150  to the access panel  110  and to cover the access opening  113 . 
         [0017]    Referring now to  FIG. 2A , illustrated is an exploded, close up vertical sectional view of the first top panel end  121  and the first access panel end  111  along line  2 - 2  of  FIG. 1 . The first tongue  114   b  and the first slot  123  are visible in the section. The first slot  123  is formed by bending the sheet metal of the top panel  120  to create a doubler  210  and a tripler  220  leaving a sufficient gap (first slot  123 ) to accept the first tongue  114   b . The tripler  220  has sufficient flex to allow the first tongue  114   b  to be pushed in, thereby aligning the locking nibs  116  with the locking apertures  126 . 
         [0018]      FIG. 2B  illustrates a close up vertical sectional view of the first top panel end  121  coupled to the first access panel end  111  along line  2 - 2  of  FIG. 1 . In general, the first tongue  114   b  and the first slot  123  may be mated without tools. However, if they resist mating, a rubber mallet may be used to make the connection. Once mated, as with most HVAC installations, disassembly is not anticipated; although it may be performed carefully without damaging the panels. 
         [0019]    Referring now to  FIG. 3 , illustrated is an isometric view of the cabinet  100  of  FIG. 1  as assembled with the door panel  150  installed. As can be seen, this embodiment provides a sleek external appearance from the perspective of the access area. The cabinet  100  may further comprise a foam seal  310  installed to seal between the access panel  110  and the cover panel  150 . The cabinet  100  may also include structure (not shown) fastened to the panels  110 ,  120 ,  130 ,  140  to customize the cabinet  100  for its intended use. These structures may be guides for holding a filter, support for an electronic air cleaner, etc. 
         [0020]    Referring now to  FIG. 4 , illustrated is an exploded isometric view of a second embodiment of an equipment cabinet  400  constructed according to the principles of the present invention. The equipment cabinet  400  comprises an access panel  410 , a top panel  420 , a back panel  430 , a bottom panel  440  and a cover panel  450 . The access panel  410  comprises a first end  411 , a second end  412 , an access opening  413 , and a plurality of female fasteners  414 . The top panel  420  comprises a first end having a first slot  423  formed therein, and a second end  422  having a second slot  424  formed therein. The access panel first end  411  and the top panel first end  421  couple in a like manner as in the embodiment of  FIG. 1 . The back panel  430  comprises a first end  431  having a first tongue  432 , and a second end  433  having a second tongue  434 . The first and second tongues  432 ,  434  are substantially normal a face  435  of the back panel  430 . The bottom panel  440  comprises a first end  441  having a first slot  442 , and a second end  443  having a second slot  444 . The back panel first tongue  432  couples to the top panel second slot  424  while the back panel second tongue  434  couples to the bottom panel first slot  442 . The bottom panel  440  couples to the access panel  410  in a manner similar to the coupling of the bottom panel  140  and the access panel  110  of  FIG. 1 . 
         [0021]    The cabinet  400  further comprises a top trim panel  460 , a pair of upper filter guides  470 , and a pair of lower filter guides  480 . The top trim panel  460  is optional and may be used to give an even more finished outer appearance to the cabinet  400 . The top panel  420  further comprises first and second longitudinal slots  425 ,  426  formed along a long side of the top panel  420 . The upper filter guides  470 ,  471  comprise vertical tabs  472 ,  473 , respectively, that fit in the first and second longitudinal slots  425 ,  426 , respectively. The bottom panel  440  further comprises first and second longitudinal slots  445 ,  446  formed along a long side of the bottom panel  440 . The lower filter guides  480 ,  481  comprise vertical tabs  482  (not visible),  483 , and filter flanges  484 ,  485 , respectively. The lower filter guide vertical tabs  482  (not visible),  483 , respectively, fit in the first and second longitudinal slots  445 ,  446 , respectively. 
         [0022]    Referring now to  FIG. 5 , illustrated is an isometric view of the cabinet  400  of  FIG. 4  as assembled with the door panel  450  installed. As can be seen, this embodiment provides a sleek external appearance both from above and from the perspective of the access area. Filter flanges  484 ,  485  can be seen as they would appear without a filter installed. The top trim panel  460  may be held in place with screws  561 . 
         [0023]    Referring now to  FIG. 6 , illustrated is an exploded isometric view of another alternative embodiment of a cabinet  600  constructed according to the principles of the present invention. The cabinet  600  comprises an access panel  610 , a top panel  620 , a back panel  630 , a bottom panel  640  and a cover panel  650 . The access panel  610  comprises a first end  611 , a second end  612 , an access opening  613  therethrough, a first outer flange  614 , a second outer flange  615 , a plurality of locking nibs  616  formed in the first outer flange  614 , a plurality of female fasteners  617 , and an outer side flange  618 . A single locking nib  616   a  is also formed at each corner of the outer side flange  618 . In the illustrated embodiment, the first outer flange  614  is configured as a first tongue  614 . The first tongue  614  and the outer side flange  618  are substantially normal a face  619  of the access panel  610 . 
         [0024]    The top panel  620  comprises a first end  621 , a second end  622 , a first slot  623  formed in the first end  621 , a second tongue  624  formed at the second end  622 , a plurality of locking apertures  626  formed in the first end  621  at the first slot  623 , and a plurality of locking nibs  627  formed in the second tongue  624 . The second tongue  624  is substantially normal a face  628  of the top panel  620 . The back panel  630  and bottom panel  640  have first and second ends  631 ,  632  and  641 ,  642 , respectively. The first and second back panel ends  631 ,  632  comprise third and fourth slots  633 ,  634 , respectively. The bottom panel first end  641  has a third tongue  643  and the bottom panel second end  642  has a fourth slot  644 . The cover panel  650  comprises a plurality of male fasteners  651  configured to cooperate with the plurality of female fasteners  617  to removeably couple the cover panel  650  to the access panel  610 . The cabinet  600  may further comprise upper and lower equipment panels  660 ,  670 , respectively, located inside of the upper and lower panels  620 ,  640 , respectively. The upper and lower equipment panels  660 ,  670 , respectively, may be fastened to the upper and lower panels  620 ,  640 , respectively, with screws  680 . The upper and lower equipment panels  660 ,  670  may be custom configured for any one of a variety of equipment such as: photocatalytic oxidation (PCO), and electronic air cleaner (EAC). 
         [0025]    Therefore, a cabinet has been described that can be stored and shipped in a knocked-down state, thereby saving storage and shipping bulk. The cabinet may be especially useful for HVAC applications involving a variety of equipment such as: air filters, photocatalytic oxidation (PCO), and electronic air cleaners (EAC) Nonetheless, the cabinet is readily assembled at the installation site and of sufficient strength to be functional for many years 
         [0026]    Although the present invention has been described in detail, those skilled in the pertinent art should understand that they can make various changes, substitutions and alterations herein without departing from the spirit and scope of the invention in its broadest form.