Abstract:
An air diffuser is adapted to be fluidly connected to an air duct. The air diffuser comprises a face and a unitary valve assembly. The face comprises a number of openings separated by louvers, which are preferably of a fixed angular orientation. The unitary valve assembly comprises vanes that are rotatably attached to a body by a deformable web that is integral to the valve assembly body and the vanes. The vanes are adjusted by means of an adjustment arm that extends from each vane through the openings in the face. The unitary valve assembly is preferably constructed of a single piece of material that is shaped so that it will attach to the face. The valve assembly is unitary, requiring no assembly except to the face. The deformable webs are sized so as to give a high cycle life to the assembly, and allow the vanes to be fixedly adjusted.

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Ser. No. 60/137,409 filed on Jun. 3, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to an air diffuser for regulating and directing the flow of conditioned air from a supply duct or ventilation system into a room or other adjoining space; and, more specifically, a closable floor diffuser having a unitary valve assembly, improving and simplifying the diffuser construction. 
     2. Related Art 
     Air diffusers are commonly used to control the flow of conditioned air from an air duct into a room. A typical air duct extends from a heating/cooling unit and terminates in an outlet at the interior surface of a structural panel, such as a floor, wall or ceiling. The duct outlet is enclosed by the air diffuser. 
     Contemporary air diffusers generally comprise a housing having one portion that is sized to be received within the duct outlet while extending through the structural panel and another portion that overlies a portion of the structural panel surrounding the panel opening and air duct outlet. Air is generally diffused by a constriction of the air passage through the diffuser, often in the form of a plurality of alternating ribs and openings. 
     Many contemporary air diffusers have a series of openings or vents that are closable by a moveable valve assembly to control the flow of conditioned air into the room. The moveable valve assembly can include a fixed grid and a moveable grid. Each grid is formed by a series of alternating ribs and openings. In the open position, the openings of each grid are aligned. In the closed position, the ribs of one grid are aligned with the openings of the other grid. 
     Another common moveable valve assembly includes a plurality of generally planar rotatable vanes, each having a longitudinal shaft, so they may be rotatably mounted within opposing openings, transversely aligned to the direction of air flow, in the air diffuser face. The vanes are then rotated about their shaft, from a generally parallel configuration, allowing maximum air flow, to a generally coplanar configuration, producing maximum constriction of the air flow. The vanes are generally planar, as stated above, but may display some degree of curvature transverse to their longitudinal axis. 
     The prior art air diffusers are relatively complex in the number of parts, the movement of parts, and their assembly. Given that, in general, air diffusers are mass produced products, any reduction in the assembly time and complexity, such as reducing the number of parts, results in a significant improvement in cost. There is a continuing need to reduce the cost of these articles. 
     SUMMARY OF THE INVENTION 
     The invention relates to an improved air diffuser for controlling the flow of air from a duct to a room. The air diffuser comprises a cover and a valve assembly. The cover has multiple spaced louvers, with openings between adjacent louvers, whereby air is directed into the room by the louvers. The valve assembly comprises a frame defining a valve opening in which is positioned a vane connected to the frame by a deformable web. The vane is rotatable an axis between a closed position where the vane substantially blocks the valve opening to substantially prevent the flow of air through the valve opening, and an open position where the vane permits the flow of air through the valve opening. The improvement relates to the vane being mounted to the frame by a deformable web, connecting the vane to the frame along the axis, whereby as the vane is rotated between the closed and open positions, the deformable web is twisted about the axis. 
     The web is preferably integrally formed with the frame and the vane. For example, the frame, vane and web can be stamped from a metal blank. The deformable web has a length to width ratio range of 2:1 to 10:1. 
     The vane can have an elongated shape with opposing ends, with a web connecting one of the opposing ends to the frame and another web connecting the other of the opposing ends to the frame. Both webs are preferably on the axis. The vane can also have a longitudinal strengthening rib. 
     The vane can further include an adjustment arm extending normally from the vane and terminating in a tip extending beyond the cover whereby the arm can be moved to rotate the vane about the axis. The arm preferably extends from the vane at a location spaced away from the axis. 
     The vane assembly can have multiple vanes, each of which can have a different axis. The vanes can be oriented such that some or all of the axes are parallel, oblique, or transverse relative to each other. 
     The frame preferably comprises a mounting flange that is generally co-planar relative to the cover and a skirt extending from the mounting flange and substantially circumscribing the valve opening to define a well, wherein the web connects to the skirt of the frame. The skirt terminates in an inwardly directed flange and the web connects to the flange. 
     In another aspect, the invention relates to a blank for forming an air diffuser valve assembly. The blank comprises a generally planar perimeter portion comprising opposing sides connected by opposing ends to define an opening in which is positioned a plate having opposing ends adjacent the perimeter portion ends and opposing sides adjacent the perimeter portion sides. The vane is connected to the planar perimeter portion by a deformable web. 
     Preferably, the vane substantially fills and is co-planar with the perimeter portion of the opening. The perimeter portion sides and the perimeter portion opposing ends each have an upper edge and a lower edge, with the lower edges intersecting to define the opening and the perimeter portion further having lower bend lines spaced from the lower edges. The perimeter portion opposing ends and perimeter portion opposing sides have an upper bend line parallel to the lower bend lines and located between the lower bend line and the upper edge. 
     The body opening preferably includes an extension projecting into one of the perimeter portion opposing sides and perimeter portion opposing ends and the plate further comprises a finger received within the body opening extension whereby when the finger is bent normally relative to the plate it forms an arm for rotating the plate about the deformable web, which has a length to width ratio of 2:1 to 10:1. 
     Other objects, features, and advantages of the invention will be apparent from the ensuing description in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings: 
     FIG. 1 is an exploded perspective view of an air diffuser according to the invention and illustrating a face with parallel louvers and openings and a valve assembly with a plurality of adjustable vanes with adjustment arms co-located at one end of the air diffuser; 
     FIG. 2 is a plan view of the assembled air diffuser of FIG. 1 showing the valve assembly beneath in phantom; 
     FIG. 3 is a sectional view taken through line  3 — 3  of FIG. 2; 
     FIG. 4 is a sectional view taken through line  4 — 4  of FIG. 2; 
     FIG. 5 is a sectional view taken through line  5 — 5  of FIG. 4; 
     FIG. 6 is a plan view of a blank from which the valve assembly of FIGS.  1 — 5  is formed; 
     FIG. 7 is a perspective view of an alternative embodiment of the valve assembly of FIGS. 1-6, with the adjustment arms located on opposing ends of the air diffuser; and 
     FIG. 8 is a perspective view of a “four-way” embodiment of the air diffuser, including transverse sets of parallel louvers and openings in the face, and incorporating the opposing adjustment arms of FIG.  7 . 
    
    
     DETAILED DESCRIPTION 
     FIGS. 1-5 illustrate a first embodiment of an air diffuser  10  comprising a face  12  and a unitary valve assembly  14  according to the invention. The face  12  is preferably of stamped or punched metal manufacture and comprises a peripheral lip  51  bound by a peripheral edge  52 , which is adapted to rest flush with a receiving, usually planar surface such as a floor or wall. The lip  51  further comprises a peripheral mounting surface  54  that is connected to the peripheral edge  52  by a transition section  53 . The peripheral mounting surface  54  is elevated relative to the peripheral edge  52  to form a gap with the receiving surface. The face  12  further comprises substantially parallel elongate face openings  56  in an upper surface of the face and separated by generally parallel elongate louvers  58  formed during the stamping process of the face  12 . The elongate louvers  58  are preferably oriented at an angle relative to the plane of the face  12  for air flow directional control. 
     The unitary assembly  14  is preferably stamped from a single piece of sheet metal, and the components bent into a configuration so that it may be assembled with the face  12  into an air diffuser  10 . The valve assembly  14 , in its use configuration, comprises a well  15  formed by opposing parallel ends or end skirts  22  and, substantially perpendicular to the end skirts  22 , opposing parallel sides or side skirts  24 . The bottom of the well is formed by substantially flat, elongate vanes  16 , which are surrounded by perimeter portions  18 . The vanes  16  each have a raised longitudinal strengthening rib  36 . The perimeter portions  18  comprise the bottom end of each of the end and side skirts  22 , 24 . Each skirt  22 , 24  is substantially perpendicular to its perimeter portion  18 , with the perimeter portions  18  extending inwardly from the skirts  22 , 24  to form the flat perimeter of the bottom of the well, with the skirts  22 , 24  forming a wall of the well. Again, interior to the perimeter portions  18 , at the bottom of the well, lie the vanes  16 . The vanes  16  are separated from the perimeter portion  18  of the end skirts  22  by an end gap  62 , and are spaced from the perimeter portion  18  of the side skirts  24  by a side gap  64 . The vanes  16  are attached to the perimeter portion  18  at each end skirt  22  by a deformable web or pivot link  26 . 
     Preferably, the width of the gaps  62 , 64  will be minimized, to allow movement of the vanes  16  while minimizing air passage when the valve assembly is closed, i.e., when the vanes  16  are aligned with the bottom of the well. The width of the gaps  62 , 64  will be determined by the method of manufacture of the unitary valve assembly  14 . 
     Each of the end skirts  22  and side skirts  24  terminates at the top in a mounting flange  20 , which extends perpendicularly to its respective skirt  22 , 24 , and to the outside of the well formed by the skirts, so as to form a substantially flat perimeter mounting flange around the top of the well. The mounting flange  20  may be then attached to the peripheral mounting surface  54  by any conventional means such as welding or mechanical affixation. 
     An adjustment arm  28  is formed at an end of each vane  16 . The arms  28  are co-located at an end of the valve assembly  14 . Each adjustment arm  28  extends generally perpendicularly from the plane of the vane  16  so as to extend up through the well beyond the plane formed by the mounting flanges  20 , and through one of the face openings  56  of the assembled air diffuser  10 , as best seen in FIG.  3 . The adjustment arm  28  has an adjustment arm opening  40  by which either a remote means of controlling the adjustment arm  28  may be used, or multiple adjustment arms  28  may be simultaneously controlled. 
     In the first embodiment illustrated in FIGS. 1-4, the pivot link  26  is depicted as extending from the longitudinal center of the vane  16 . However, this is not a strict limitation as to the location of the pivot link  26 , which, depending on the desired rotation, can be placed at any longitudinal location. 
     The preferred embodiment of the air diffuser and the unitary valve assembly  14  is made from a metal stamping, typically steel. The unitary valve assembly  14  is preferably stamped from flat stock sheet metal, resulting in a unitary construction. The flat stamping is then bent to form the well  15  as has been described above in FIGS. 1-4. When the unitary valve assembly is first stamped, the vanes  16  are substantially coplanar with the perimeter portion  18 . Upon shaping of the valve assembly, the vanes  16  and perimeter portion  18  will initially remain coplanar to each other, perpendicular to the skirts  22 , 24 , and parallel to the mounting flanges  20 . 
     FIG. 6 is an example blank for making the unitary valve assembly  14 . The figure shows that each of the end skirts  22  and side skirts  24  have upper edges  22   a ,  24   a  and lower edges  22   b ,  24   b , which are connected by side edges  22   c ,  24   c , respectively. The side edges  22   c ,  24   c  of adjacent end skirts  22  and side skirts  24  overlap and form intersections  70 . The lower edges  22   b ,  24   b  form intersections  72  and collectively define the perimeter of the opening in which the vanes  16  lie. 
     In this embodiment, the adjustment arms  28  are cut out of one end  22 , but this is not a strict limitation, as the adjustment arms may be situated on opposing ends of the vanes  16 . 
     The pivot links  26  comprise a web extending from the plate or vane  16  to the adjacent end  22 . 
     Bend lines  74  extend between the intersections  70  for each skirt end  22  and side  24 . The sides  24  overlap the ends  22  so that when the ends  22  and sides  24  are bent along bend lines  74 , the perimeter  18  of the well  15  is formed. Bend lines  76  extend across the span of each end  22  and side  24 . When the ends  22  and sides  24  are bent along the mounting flanges  20  are formed around the perimeter of the stamping. Bend lines  78  are located at the intersection of the arms  28  with the plate forming the vanes  16 . 
     The manufacture of the vane assembly will now be described. It should be noted that the manufacture includes many steps, especially the bending steps, whose sequence is unimportant to the invention. Therefore, the sequence described is merely for illustration purposes and not limiting to the invention. During the manufacture of the vane assembly, a planar sheet is stamped to form the blank shown in FIG.  6 . The arms  28  are formed by bending the arms along the bend line  78  until the arms  28  are approximately perpendicular to the plane of the blank. The ends  22  and sides  24  are then bent downwardly relative to the blank as seen in FIG. 6 along bend lines  76  to form the mounting flanges  20 . The ends  22  and sides  24  are then bent upwardly relative to the blank along bend lines  74  until they are substantially perpendicular to the plane of the blank to form the ends and sides and the perimeter  18 . 
     Once the vane assembly is bent into its desired shape as described, the vane assembly is positioned relative to the cover  12  such that the arms  28  pass through the one of the openings in the cover  12  and the mounting flanges  20  abut the lip  51  if the cover  12 . The mounting flanges  20  are then welded or otherwise secured to the cover  12  to complete the assembly. 
     The pivot link  26  has a pivot link length  30 , and a pivot link width  32 . The pivot link length  30  and pivot link width  32  must be selected carefully so as to provide sufficient stiffness to fixedly adjust the vanes  16 , while providing sufficient malleability to allow manual adjustment and cycle life for the material used in the stamping. A ratio of the pivot link length  30  to the pivot link width  32  ranging from 2:1 to 10:1, depending upon the thickness and properties of the material used, has been found to provide satisfactory performance, but is not strictly limiting as to the proportions which will provide satisfactory performance. 
     The adjustment arms  28  have an adjustment arm length  34 . It is desirable to have an adjustment arm length  34  such that the mounting flange  20 , adjacent to the end skirt  22 , does not have a gap where it will be attached to the peripheral mounting surface  54 . The adjustment arms  28  have a length  34  so that the arms will extend through one of the face openings  56 . The adjustment arms are spaced a predetermined distance from the pivot links to form a lever arm  35 , whose length is selected to provide a sufficient lever arm to enable adjustment at a predetermined force, preferably a force capable of being applied by the weakest of the anticipated users. The various dimensions of the vanes  16  (the link width  32 , the link length  30 , the arm length  28 , lever arm  35 ) are all selected in combination with the material properties to provide the predetermined minimum force for rotating the vane  16  about the links for a desired life cycle. 
     FIG. 7 depicts an alternative embodiment of the unitary valve assembly  14  wherein the adjustment arms  28  on adjacent vanes  16  are on opposing ends. Since the arms are located near the closest skirt  24 , the greatest vane rotation occurs by moving the arm away from the nearest skirt, resulting in the counter-rotation of the vanes  16 . In some applications, it is desirable to have the vanes  16  rotated in opposing directions and independently. By placing the adjustment arms on the opposing ends, the vanes  16  may be adjusted inwardly in an opposing manner without interference between the adjustment arms  28 . 
     FIG. 8 is a perspective view of a “four-way” embodiment of the air diffuser  10 ′. The face openings  56 ′ and louvers  58 ′ in this alternative embodiment are grouped in subsets that are not all substantially parallel to each other, providing for air flow in multiple directions. It should be borne in mind that the array of vanes  16 ′ may vary in length and width and in the number of vanes  16 ′ in the array. The square array of FIG. 8 would likely have more than the two vanes  16 ′ depicted in the first and second embodiments. It could likely have them adjustable in an opposing manner, as described in FIG. 7, or in any manner so as to facilitate the smooth flow of air through the unitary valve assembly  14 ′ and between the fixed louvers  58 ′. This embodiment further comprises mounting holes  55 ′ for mounting the air diffuser  10 ′ to a planar surface. 
     While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. 
     Examples of alternate embodiments that may be foreseen are dimensional and configurational alterations of the preferred embodiments, and the substitution of materials used in the unitary valve assembly, such as certain suitable plastics or other materials. 
     While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.