Abstract:
A diffuser for a heating and air conditioning system includes a body portion and an adapter. The body portion includes a flange with a cylindrical portion. Flexible arms having projections are located about the cylindrical portion. Clamp guides are positioned about the cylindrical portion as well. The adapter includes multiple, different size cylindrical sections. One of the sections includes openings for receiving the projections on the arms to secure the adapter to the body. A tear-away strip is provided to remove unneeded sections of the adapter. Two attachment mechanisms are provided for securing the diffuser to a ceiling. The diffuser further includes a removable vane unit. The vane unit includes multiple projections for engaging prongs on the base to secure the vane unit to the base. A ribs on the projections contact the prongs to limit vibrations. The diffuser baffles include a collar for reducing vibrations.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an air diffuser for heating and air conditioning systems and, in particular, to an air diffuser including an adapter for attaching the diffuser to duct work of varying sizes. 
     2. Discussion of the Prior Art 
     Numerous types of air diffusers for heating and air conditioning systems are known in the prior art. Such diffusers are used to deflect the flow of air from the heating and air conditioning duct such that it is not all directed to one location. Examples of various diffusers are shown in U.S. Pat. No. 2,977,869 to O&#39;Day, U.S. Pat. No. 3,110,242 to O&#39;Day, U.S. Pat. No. 3,866,950 to Shock et al., U.S. Pat. No. 4,473,000 to Perkins, U.S. Pat. No. 5,109,756 to Barboza et al., and U.S. Pat. No. 5,410,782 to Holyoake. 
     SUMMARY OF THE INVENTION 
     In one embodiment of the present invention, an air diffuser for a heating and air conditioning system includes a flange, a first cylindrical portion connected to the flange, a projection connected to the first cylindrical portion, an adapter and an opening in the adapter for receiving the projection. A flexible arm may be connected to the cylindrical portion and the projection may be connected to the arm. The adapter may include a second cylindrical portion that fits within the first cylindrical portion. Insertion of the second cylindrical portion into the first cylindrical portion causes movement of the projection. The opening may be located in the second cylindrical portion. The adapter may be rotated within the first cylindrical portion to align the opening and the projection. Further rotation of the adapter disengages the projection from the opening. The projection prevents movement of the adapter relative to the first cylindrical portion in at least one direction when the projection is located in the opening. In one embodiment, the projection includes a camming surface and further rotation of the adapter in one direction causes the camming surface to ride along the periphery of the opening and disengage the projection from the opening. 
     In another embodiment of the invention, a diffuser includes a body, a pair of prongs extending from the body, a vane unit and a projection extending from the vane unit. The projection includes an enlarged portion and a rib on the enlarged portion. The projection fits within a space between the prongs. Inserting the projection into the space between the prongs causes the prongs to move away from each other. The prongs are biased toward the projection when the projection is located between the prongs. 
     In another embodiment of the invention, a diffuser includes a first portion for connection to a duct, a plurality of baffles, a projection connected to the baffles and extending through the first portion and a collar located about the projection. The collar spaces the baffles from the first portion. 
     In yet another embodiment of the invention, a diffuser includes a first portion, a clamp for securing a duct to the first portion and a guide for locating the clamp. The guide includes a plurality of ridges extending from the cylindrical portion. 
     In another embodiment of the invention, a diffuser includes a flange, a first portion for connection to a duct, the first portion connected to the flange, a plurality of fins connected to the first portion and a seal located adjacent the fins. The fins include notches and the seal rests in the notches. The seal is a compressible member. 
     In another embodiment of the invention, a diffuser includes a first portion, an adapter, first means for preventing vertical movement of the adapter relative to the first portion, and second means for preventing rotation of the adapter relative to the first portion in at least one direction. 
     Other features of the present invention will be apparent to those skilled in the art from the following detailed description of the preferred embodiments and accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of an air diffuser according to one embodiment of the present invention. 
     FIG. 2 is a partial sectional view taken along line  2 — 2  in FIG.  1 . 
     FIG. 3 is a partial view of an adapter that is a component of the diffuser shown in FIG. 1, illustrating removal of a portion of the adapter. 
     FIG. 4 is an exploded perspective view of the opposite side of the diffuser shown in FIG.  1 . 
     FIG. 5 is a partial, sectional view showing engagement of a vane unit that is a component of the diffuser shown in FIG. 1 with the base of the diffuser. 
     FIG. 6 is a detailed view of the area shown in circle  6  in FIG.  1 . 
     FIG. 7 shows the adapter with a portion removed, secured to the base. 
     FIGS. 8 and 9 are sectional views taken along line  8 — 8  in FIG. 7 showing the manner in which the adapter is secured to the base. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 is an exploded perspective view of an air diffuser according to one embodiment of the present invention. The diffuser generally includes an adapter  10  and a base  20 . Adapter  10  includes a first cylindrical portion  11 , a second cylindrical portion  12 , and a third cylindrical portion  13 . Cylindrical portion  12  has a smaller diameter than cylindrical portion  11  and cylindrical portion  13  has a smaller diameter than cylindrical portions  11  and  12 . Cylindrical portion  11  includes a first end  11 A and an opposite, second end  11 B. A flange  11 C extends from second end  11 B. Cylindrical portion  11  further includes a plurality of openings  11 D located around the perimeter of cylindrical portion  11 . A plurality of openings  11 E is located around the perimeter of second end  11 B and communicates with openings  11 D. Second cylindrical portion  12  includes a first end  12 A secured to second end  11 B of cylindrical portion  11  and a second, opposite end  12 B. A dimple  12 C is located in second end  12 B. Dimple  12 C is adapted to permit removal of tear-away strip  12 D defined by indentations or scores  12 E (FIGS.  2  and  3 ), as described below. Third cylindrical portion  13  includes a first end  13 A attached to second end  12 B of cylindrical portion  12  and a second, opposite end  13 B. An opening  14  extends through cylindrical portions  11 ,  12 , and  13 . A plurality of clamp guides  15  are spaced about cylindrical portions  12  and  13 . In the embodiment shown, clamp guides  15  are a plurality of ridges formed on cylindrical portions  12  and  13 . 
     Base  20  generally includes a flange  30 , a cylindrical portion  40 , and locking assemblies  50 . Flange  30 , in the embodiment shown, is a generally square member including a first side  31 , a second side  32 , a plurality of mounting openings  33 , and a plurality of prongs  34  (FIGS. 4 and 5) extending from second side  32 . Prongs  34  each include a first inclined surface  35  and a second oppositely inclined surface  36 . 
     Cylindrical portion  40  includes a first end  41  connected to flange  30  and a second end  42 . Cylindrical portion  40  includes a first section  43  delineated from a second diameter section  44  by a ridge  45 . Cylindrical portion  40  has a central opening  46 . A plurality of clamp guides  47  is formed around section  44 . In the embodiment shown, clamp guides  47  are a plurality of ridges formed on section  44 . A plurality of arms  48  (FIGS. 1 and 6) are located around the perimeter of section  44  and are used to secure adapter  10  to base  20 , as described below. Each arm  48  includes a projection  48 A having a first sloped or camming surface  48 B adjacent the top portion thereof and a second sloped or camming surface  48 C adjacent one side thereof. Surfaces  48 B and  48 C extend inwardly toward opening  46  of cylindrical portion  40  and terminate in a face  48 D. Side  48 E of projection  48 A opposite surface  48 C is a generally flat surface. 
     Locking assemblies  50  generally include dogs  51 , screws  52 , studs  53 , and stops  54 . Screws  52  extend through flange  30 , through dogs  51  and into studs  53 . Dogs  51  are connected to screws  52  such that rotation of screws  52  causes rotation of dogs  51 . Movement of dogs  51  is limited in one direction by section  43  of cylindrical portion  40  and in the other direction by stops  54 . 
     A plurality of projections  60  having notches  61  are connected to first section  43  of cylindrical portion  40  and to first side  31  of flange  30 . A seal  62  (a portion of which is shown in FIG. 1) rests in notches  61 . Seal  62  is preferably a compressible foam or rubber member. 
     Vane unit  70  (FIGS. 4 and 5) includes a plurality of vanes  71  for diverting airflow out of the diffuser. Vane unit  70  further includes an opening  72  for operating the dampers of the diffuser, as described below. Vane unit  70  also includes a plurality of projections  73  for securing vane unit  72  of flange  30  as described below. Each projection  73  includes an enlarged portion  74  having a rib  75 . 
     Damper mechanism  80  (FIGS. 1 and 4) includes baffles  81  secured to cylindrical portion  40  by a projection  82  extending through cylindrical portion  40 . A standoff or collar  83  is formed on projection  82  to space it from section  43  of cylindrical portion  40 . A drive mechanism  84  is positioned in line with opening  72  on vane unit  70  to permit adjustment of baffles  81 . 
     To install the diffuser, a hole is cut in the ceiling, wall or other surface to which the diffuser is to be secured. A duct  90  is then extended through the opening and connected to the diffuser. Depending upon the size of duct  90 , adapter  10  may or may not be needed. If the adapter is not to be used, duct  90  is positioned around second section  44  of cylindrical portion  40  and secured with a tie-wrap or band clamp. The wrap or clamp is positioned about duct  90  between guides  47  and tightened to secure duct  90  to cylindrical portion  40 . Note that guides  47  (or  15  if adapter  10  is used) also grip duct  90  to help hold duct  90  in place. 
     If adapter  10  is to be used, cylindrical portion  11  is positioned over second section  44  of cylindrical portion  40 . Adapter  10  is then lowered into cylindrical portion  40 . As this occurs, first end  11 A of cylindrical portion  11  pushes against surface  48 B of projection  48 A causing arm  48  to flex away from the center of opening  46 . This continues until cylindrical portion  11  is inserted far enough such that face  48 D comes in contact with the outer surface of cylindrical portion  11 . Adapter  10  is further inserted until flange  11 C contacts end  42 A of section  42 . Adapter  10  is then rotated, in the embodiment shown, in a counter-clockwise direction. When projections  48 A are aligned with openings  11 D, they will snap inwardly into place to secure adapter  10 . Rotation can continue until the edges of openings  11 D contact sides  48 E of projections  48 A. 
     Note also that if openings  11 D are aligned with projections  48  when adapter  10  is inserted, arms  48 A will move into position so that the projections  48 A are engaged with openings  11 D upon full insertion of adapter  10  without the need to rotate adapter  10 . To remove adapter  10 , adapter  10  may be rotated in the opposite direction, clockwise in the embodiment shown, such that an edge of opening  11 D contacts surface  48 C of projection  48 A. Continued rotation causes arm  48  to move outwardly and release projection  48 A from opening  11 D. Adapter  10  may then be removed. 
     Once adapter  10  is fully inserted and engaged, duct  90  may be attached directly to cylindrical portion  13  by utilizing a band clamp or tie wrap in the manner described above. Alternatively, if an intermediate-sized duct is to be used by attaching it to cylindrical portion  12 , pliers or another tool are used to puncture dimple  12 C and grip tear-away strip  12 D (FIG.  3 ). The pliers are then used to remove tear-away strip  12 D from the remainder of adapter  10 , thereby separating cylindrical portion  13  from cylindrical portion  12 . Duct  90  is then secured to cylindrical portion  12  in the manner described above. 
     Once duct  90  has been secured to either cylindrical portion  40  or adapter  10 , duct  90  and the diffuser are pushed toward the ceiling until flange  30  abuts the ceiling. Screws  52  are then rotated to move dogs  51  into contact with stops  54 . Further rotation causes dogs  51  to travel downwardly along screw  52  toward flange  30 , ultimately clamping the ceiling between dogs  51  and flange  30 . Note that as this occurs, the ceiling will compress seal  62 , thereby reducing the possibility that air from above the ceiling will escape around adapter  10  or cylindrical portion  40 , will escape between the ceiling and flange  30  and into the room. Note that screws or similar fasteners can be inserted through opening  33  as an alternative to or in combination with use of dogs  51  to secure the diffuser to the ceiling. 
     To secure vane unit  70  to flange  30 , projections  73  are positioned adjacent prongs  34  and inserted so as to ride against surfaces  35  and cause prongs  34  to flex outwardly. This continues until rib  75  is positioned adjacent surface  34  as shown. Because prongs  34  are flexible, this biases prongs  34  inwardly and holds vane unit  70  in place. Contact between prongs  34  and ribs  75  reduces vibrations of vane unit  70 . Vane unit  70  may be removed by simply pulling on vane unit  70  to disengage projections  73  from prongs  34 . Note that various interchangeable vane units having different vane configurations may be provided for use with the diffuser. 
     Baffles  81  of damper  80  may be adjusted by inserting a screwdriver or similar tool through opening  72  in vane unit  70  and operating drive mechanism  84 . Collar or standoff  83  provides clearance for baffles  81  about the interior of cylindrical portion  40  and, because of their close proximity to the interior of cylindrical portion  40 , reduce vibrations. 
     Although the present invention has been shown and described in detail, the same is for purposes of example only and not intended to be a limitation on the invention. Numerous changes to the embodiments disclosed will be apparent to those skilled in the art. Accordingly, the scope of the present invention is to be limited only by the claims appended hereto.