Patent Publication Number: US-10323853-B2

Title: Ventilation system and method

Description:
BACKGROUND 
     Ventilating exhaust fans, such as those typically installed in bathrooms, draw air from within an area and pass the exhausted air out to another location, such as through a vent in the gable or roof of a home or other building structure. The exhaust fan is usually positioned adjacent an aperture in a wall or ceiling, and secured in a number of conventional manners, such as by being attached to wall or ceiling joists, or by being attached to another other structure in the wall or ceiling. Centrifugal exhaust fans typically include a rotating fan wheel having a plurality of vanes that create an outward airflow which, in turn, is directed out of an outlet opening. The fan wheel is typically coupled to a motor supported within the fan housing, and the motor drives the fan wheel, thus providing ventilation to an area. In some cases, a curved fan scroll is employed to channel air around the fan, and can be defined by a housing wall of the fan or by a separate element within the fan housing. During operation, most modern ventilating exhaust fans do not run silently. The noise emission and audible noise can depend on a variety of factors, including but not limited to the size and type of motor, the fan wheel and/or scroll design and the size, and shape of the ventilation inlet and outlet. 
     SUMMARY 
     Some embodiments of the invention provide a ventilation assembly including a discharge grid. In some embodiments, the discharge grid comprises an outlet restriction, including a restriction wall with an inner surface and a first edge and a second edge. In some embodiments, the discharge grid comprises a plurality of vertical fins and horizontal fins. In some embodiments, the discharge grid includes a main wall coupled to the first edge and the inner surface. The main wall includes a first end and a second end and first and second surfaces. 
     In some embodiments, the plurality of vertical fins includes a first vertical fin including a top edge and a bottom edge. In some embodiments, the bottom edge of the first vertical fin is coupled to the restriction wall at the second edge and the inner surface. In some embodiments, a plurality of horizontal fins are coupled to the second surface of the main wall and the inner surface of the restriction wall and the first vertical fin. In some embodiments, at least one of the plurality of horizontal fins extends from the outlet restriction to couple with at least one other vertical fin and form at least one aperture. Some embodiments also include a base wall coupled to the second end of the main wall and the bottom edge of the first vertical fin. 
     Some embodiments provide a ventilation assembly including a scroll assembly. In some embodiments, the scroll assembly comprises a scroll housing including an inner scroll surface. In some further embodiments, the scroll assembly includes a scroll crescent including a first crescent end and a second crescent end. In some embodiments, the scroll crescent can include a substantially incurvated surface, and a substantially convex surface coupled to the inner scroll surface of the scroll housing. In some embodiments, the substantially convex surface is coupled to the first crescent end and the second crescent end and the substantially incurvated surface. Some embodiments include a ventilation assembly with a scroll crescent that is integrally formed with the inner scroll surface of the scroll housing. In other embodiments, the scroll crescent comprises a discrete component coupled to the inner scroll surface of the scroll housing. Some further embodiments of the ventilation assembly include a blower assembly including a motor coupled to a blower wheel. 
     In some embodiments of the ventilation assembly, at least a portion of at least one of the plurality of vertical fins includes a flared surface. In some other embodiments, at least a portion of at least one of the plurality of horizontal fins includes a flared surface. Some embodiments include one or more flared surface surfaces that include a flare bottom surface comprising a flare bottom length, and a flare top surface comprising a flare top length. In some embodiments, the flare top surface and flare bottom surface is at least partially curved. In some embodiments, the flare top length and flare bottom length is substantially equal, whereas in other embodiments, the flare top length and flare bottom length are unequal. 
     Some embodiments include a discharge grid comprising at least one coupling pin. In some embodiments, the discharge grid is configured and arranged to be coupled to the scroll by coupling the at least one coupling pin with at least one scroll pin coupling hole. 
     Some embodiments include a discharge grid with at least one fastener coupling hole and the scroll includes at least one scroll fastener coupling hole. In some embodiments, the discharge grid is further configured and arranged to be coupled to the scroll using at least one fastener secured through the at least one fastener coupling hole and through at least one scroll fastener coupling hole. 
     Some embodiments include a discharge grid that further includes a flange coupled to the main wall. In some embodiments, the flange includes a coupling edge including at least one snap tab. Some embodiments also include a base wall that includes at least one snap tab. In some embodiments, the scroll includes at least one snap slot and at least one vertical slot and at least one snap slot. In some embodiments, the discharge grid is secured to the scroll by coupling the at least one snap tab with the at least one snap slot. In other embodiments, the discharge grid is secured to the scroll by coupling the coupling edge with the vertical slot. In some further embodiments, the discharge grid is secured to the scroll by coupling the at least one snap tab with the at least one snap slot and by coupling the coupling edge with the vertical slot. 
     In some embodiments, the scroll crescent is positioned within the scroll so that the scroll crescent is positioned within the scroll with the first crescent end substantially 80° or more from the first wall of the inner scroll surface. In some further embodiments, the scroll crescent is positioned within the scroll so that the second crescent end is substantially 170° or less from the first wall of the inner scroll surface. In some other embodiments, the scroll crescent is positioned within the scroll so that the first crescent end is positioned substantially at 90° from the first wall of the inner scroll surface, and the second crescent end is substantially at 180° from the first wall of the inner scroll surface. 
     Some embodiments include a ventilation assembly where at least one of the plurality of vertical fins and at least one the plurality of horizontal fins form at least one perpendicular intersection. In some embodiments, the discharge grid is configured and arranged to guide air exiting the scroll housing in at least two different directions. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A-D  show perspective views of a scroll assembly according to one embodiment of the invention. 
         FIG. 1E  shows an assembly view of a scroll assembly according to one embodiment of the invention. 
         FIGS. 2A-C  shows perspective views of a scroll assembly according to another embodiment of the invention. 
         FIGS. 3A-C  show perspective views of a scroll assembly according to one embodiment of the invention. 
         FIG. 3D  shows an assembly view of a scroll assembly according to one embodiment of the invention. 
         FIG. 4A  is a perspective view of a discharge grid according to one embodiment of the invention. 
         FIG. 4B  is a perspective view of a discharge grid according to one embodiment of the invention. 
         FIG. 4C  is a perspective view of a discharge grid according to one embodiment of the invention. 
         FIG. 5  is side perspective view of a discharge grid according to one embodiment of the invention. 
         FIG. 6A  is a partial perspective view of a discharge grid with snap-feature according to one embodiment of the invention 
         FIG. 6B  is a partial perspective view of a scroll showing a snap-feature receptacle according to one embodiment of the invention. 
         FIG. 7A  is a partial perspective view of a discharge grid assembled into a scroll according to one embodiment of the invention. 
         FIG. 7B  is a partial perspective view of a discharge grid assembled into a scroll according to one embodiment of the invention. 
         FIG. 8A  is a top perspective view of a discharge grid according to one embodiment of the invention. 
         FIG. 8B  is a bottom perspective view of a discharge grid according to one embodiment of the invention. 
         FIG. 9A  is a front perspective view of a discharge grid according to one embodiment of the invention. 
         FIG. 9B  is a perspective view of a discharge grid showing snap-features according to one embodiment of the invention. 
         FIG. 9C  is a partial perspective view of a discharge grid snap-feature according to one embodiment of the invention. 
         FIG. 9D  is a partial perspective view of a scroll assembly with a discharge grid snap feature attachment region according to one embodiment of the invention. 
         FIGS. 9E-9H  illustrates various perspective views of a discharge grid according to another embodiment of the invention. 
         FIG. 10A  illustrates a perspective view of a blower assembly according to one embodiment of the invention. 
         FIG. 10B  illustrates a perspective view of a ventilation assembly according to one embodiment of the invention. 
         FIG. 10C  illustrates a front perspective view of the ventilation assembly according to one embodiment of the invention. 
         FIG. 11  shows a graph of noise level as a function of noise pressure for a conventional ventilation assembly versus the ventilation assembly according to one embodiment of the invention. 
         FIG. 12A  illustrates a plot of a fluid dynamic simulation showing a velocity profile at a fan exit without fluid flow modifiers. 
         FIG. 12B  illustrates a plot of a fluid dynamic simulation showing a velocity profile at a fan exit with fluid flow modifiers. 
     
    
    
     DETAILED DESCRIPTION 
     Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. 
     The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention. 
     In some embodiments, the ventilation assembly  10  can be used to ventilate any room, area or space. In some embodiments, the ventilation assembly  10  can be secured within a wall, ceiling, or other building structure in a partially, or fully recessed position. In some embodiments, the ventilation assembly  10  can be installed within an intermediate space, outside of the room, area or space, and coupled with one or more ventilation duct assemblies to extract a fluid from the room, area or space. In some other embodiments, the fluid may comprise air, or other gases, or vapor, such as water vapor. In some embodiments, the fluid may comprise smoke, ash, or other particulate in addition to air or other gases. 
     In some embodiments, the ventilation assembly  10  can be installed as a new, original equipment installation in a room or building where none had previously existed, whereas some embodiments of the invention provide a ventilation assembly  10  that can replace a pre-existing ventilation system. In some embodiments, the assembly  10 , can be installed as a new, or a replacement ventilation system, and in some embodiments, the assembly  10  can replace an existing assembly  10 . 
     Some embodiments of the ventilation assembly  10  can include several components and devices that can perform various functions. In some embodiments, the ventilation assembly  10  can include a housing  20 , which can house the various components and devices of the ventilation assembly  10 . For example, in some embodiments the ventilation assembly  10  can generally include the blower assembly  15  as shown in  FIG. 10A . In some embodiments, the blower assembly  15  can be substantially housed within the housing  20 , and positioned and anchored to the housing  20  aided by at least one retention feature  34 . In some embodiments, the blower assembly  15  can generally include motor  52  (for example a permanent split capacitor motor), and may include a conventional motor capacitor (not shown). Some embodiments provide a blower assembly  15  that can also include a scroll  30  comprising a scroll housing  31  including an inner surface  44  formed between a first wall  45   a  and a second wall  45   b , and a blower wheel  50  positioned substantially within the scroll  30  and mechanically coupled to the motor  52 . In some embodiments, the motor  52  is electrically coupled to a conventional motor power harness (not shown). 
     In some embodiments, the ventilation assembly  10  includes a duct connector assembly  58  (shown in  FIG. 10B ) configured and arranged for coupling with a conventional ventilation orifice (not shown). In some embodiments, the duct connector assembly  58  can include a damper flap  60  that is coupled with the ventilation orifice  62 . Some embodiments can include a duct connector assembly  58  including a damper flap  60  that is capable of being moved within the ventilation orifice  62  to substantially control the backflow of a fluid into the ventilation orifice  62 . Furthermore, in some embodiments, the duct connector assembly  58  is further capable of substantially controlling the flow of fluid from a space into the ventilation of a duct of building (not shown) when the motor  52  is unpowered. 
     In some embodiments, the scroll  30  can be formed into any shape, but generally is shaped to provide a substantially laminar fluid flow towards a discharge outlet  35 . In one embodiment, the discharge outlet can be defined at least partially by a first wall  35   a  and a second wall  35   b  opposing the first wall  35   a . In some embodiments, the first and second opposing walls  35   a ,  35   b  can extend from a top  35   d  of the discharge outlet  35  to a bottom  35   c  of the discharge outlet  35 . The scroll  30  may be formed from any material that is readily shaped, including, but not limited to, polymers, polymer-composites, metal, ceramic, or wood, or paper-based composite or laminate. Furthermore, the use of injection-molded or thermo-formed polymeric materials conveniently allows a variety of functional or aesthetic components to be included into the structure of the scroll  30 . In some embodiments, one or more functional or aesthetic components can be integrally formed within the scroll  30  using one or more thermoplastic polymers and injection-molding technology, thermo-molding or other molding technology. In other embodiments, one or more thermosetting polymer precursors may be used with a thermo-molding or other molding technology. 
     In some other embodiments, the use of injection-molded or thermo-formed polymeric materials conveniently allows a variety of functional or aesthetic components to be included and formed as discrete components, and then attached to the scroll  30  using adhesive, fasteners, thermo-molding or other melt-attachment process. In some embodiments, one or more functional and/or aesthetic components can be formed and then later attached to the scroll  30  using one or more thermoplastic polymers and injection-molding technology, thermo-molding or other molding technology. In other embodiments, one or more thermosetting polymer precursors may be used with a thermo-molding or other molding technology to form a component and then later attached to the scroll  30 . In some other embodiments, the scroll  30  may utilize a combination of integrally formed and discrete components attached to the scroll  30 . 
     In some embodiments, the main housing  20  may be formed into any shape, included but limited to, a rectangular box-like shape, an oval shape, a hemispherical shape, a spherical shape, a pyramidal shape, or any other shape. In some embodiments the main housing  20  is formed from a sheet metal, including, but not limited to an aluminum-based metal, a steel or iron-based metal, a zinc-based metal, or a nickel and tin-based metal. In some other embodiments, the main housing  20  may be formed from injection molded polymers, thermo-formed polymers, thermosetting polymers, or sheet metal, or any other suitable material. In some other embodiments, the housing  20  may comprises a wood-based product, such as wood, or particle-board or wood laminate. In some other embodiments, the housing  20  can form a base or a similar support structure of the ventilation assembly  10 . 
     Some embodiments can include at least one component suitable for modifiying a flow of fluid within the scroll assembly  25 . In some embodiments, this can include the addition of at least one component that can reduce noise creation with the main housing  20 . For example, some embodiments include at least one noise reduction feature  65 ,  300 ,  305 . For example, some embodiments of the scroll assembly  25  include a discharge grid  65 . For example, as shown in the various perspective views of a scroll assembly according to one embodiment in the  FIGS. 1A-1B and 2A-2B , in some embodiments, a discharge grid  65  can be positioned at the discharge outlet  35  and attached to the scroll  30  to form a scroll assembly  25 . In some embodiments, the discharge grid  65  may be formed from any material that is readily shaped, including, but not limited to, polymers, polymer-composites, metal, ceramic, or wood, or paper-based composite or laminate, or metals. In some embodiments, the use of injection-molded or thermo-formed polymeric materials conveniently allows a variety of functional or aesthetic features to be included into the structure of the discharge grid  65 . In some embodiments, one or more functional or aesthetic components can be integrally formed within the discharge grid  65  using one or more thermoplastic polymers and injection-molding technology, thermo-molding or other molding technology. In other embodiments, one or more thermosetting polymer precursors may be used with a thermo-molding or other molding technology. In some other embodiments, the use of injection-molded or thermo-formed polymeric materials conveniently allows the discharge grid  65  to be formed integral with the scroll  30 . In some other embodiments, the discharge grid  65  can be formed as a discrete component and then later attached to the scroll  30 . 
     In some embodiments the discharge grid  65  can include one or more structures designed to at least partially obstruct fluid flow. For example, in some embodiments, the discharge grid  65  can include an outlet restriction  67 . In some embodiments, the outlet restriction  67  can be integrally formed with the discharge grid  65 , and in other embodiments, the the outlet restriction  67  can be formed as a discrete component and assembled with the discharge grid  65 . 
     As shown in  FIGS. 1A-1C , in some embodiments, the discharge grid  65  can be coupled to the scroll using at least one pin  66 . Further, as shown in  FIGS. 9E-9H , in some embodiments, the grid  65  can include at least one coupling pin  66 . As shown, in some embodiments, the first horizontal fin  90  and the second horizontal fin  100  can include a coupling pin  66 . In some embodiments, the discharge grid  65  can be secured to the scroll  30  by inserting the pins  66  of the grid  65  into pin coupling holes  66   a  within the body of the scroll  30  (see for example the holes  66   a  in  FIG. 1E ). 
     Some embodiments include a scroll gasket  28 . In some embodiments, one or more scroll gaskets  28  can be applied to the scroll housing  31  to at least partially surround the discharge outlet  35  as shown in  FIG. 1D-1E . In some embodiments, the one or more scroll gaskets  28  can provide a seal for coupling with at least one other component of the ventilation assembly  10 , such as the duct connector assembly  58  and/or the housing  20 . In some embodiments, the scroll gaskets  28  can provide vibration isolation and reduce noise. 
     In some embodiments, as fluid flows within the scroll  30  and approaches the outlet  35 , the outlet restriction  67  can at least partially impede the flow of fluid within the scroll  30 . Some embodiments include an outlet restriction  67  with a restriction wall ( 130  in  FIGS. 4A-4C ) that can at least partially change the flow of fluid within the scroll  30 . 
     Some embodiments of the invention include a discharge grid  65  including an outlet restriction  67  that includes a main wall  150 , including a first end  150   a , a second end  150   b , and several surfaces including a first surface  150   c , and a second surface  150   d . In some embodiments, the outlet restriction  67  includes a restriction wall  130 . In some embodiments, the restriction wall  130  includes a first wall  135  coupled to a second wall  140 . In some embodiments, the second wall  140  is further coupled to the main wall  150 . A base wall  170  is coupled to the main wall  150  and the restriction wall  130  in some embodiments. In some embodiments, the base wall includes a first end  170   a , a second end  170   b , a top base edge  170   c , and a bottom base edge  170   d . In some embodiments, the first end  170   a  is coupled with the second end  150   b  at the second surface  150   d , and the bottom base edge  170   d  is coupled with the restriction wall  130 . In some further embodiments, the second end  170   b  of the base wall  170  is coupled to a first vertical fin  80 . As depicted, for example, in  FIG. 4B , the first vertical fin  80  comprises a top edge  81   a  and a bottom edge  81   b . As can be seen, for example, in  FIG. 7A , the bottom edge  81   b  of the first vertical fin  80  is configured to be located upstream of the top edge  81   a  of the first vertical fin  80  when the discharge grid  65  is located in the discharge outlet  35 . The first wall  135  of the restriction wall  130  extends from the bottom edge  81   b  of the first vertical fin  80  to the second wall  140  of the restriction wall  130 , which extends to the main wall  150 . As depicted in  FIGS. 3C and 7A , because the first wall  135  extends from the upstream, bottom edge  81   b  of the first vertical fin  80  the first wall  135  of the restriction wall  130  is located at the upstream edge of the first vertical fin  80 . Therefore, when the discharge grid  65  is located in the discharge outlet  35 , the first wall  135  of the restriction wall  130  is located upstream of the discharge outlet  35 . Moreover, when the discharge grid  65  is located in the discharge outlet  35 , the restriction wall  67  extends from adjacent one of the first and second opposing walls  35   a ,  35   b  defining the discharge outlet  35  and substantially between the top  35   d  and bottom  35   c  of the discharge outlet  35 . 
     In some embodiments, as fluid flows within the scroll  30  and approaches the outlet  35 , the outlet restriction  67  can at least partially substantially block the flow of fluid within the scroll  30 . In some embodiments, the outlet restriction wall  67  can extend inward from the discharge outlet  35  of the scroll  30  toward the blower wheel  50  as depicted, for example, in  FIGS. 1A, 1C, 1D, 7A . In other embodiments, the outlet restriction  67  can at least partially redirect and/or modify the velocity profile of the flow of fluid within the scroll  30 . In embodiments where the scroll  30  at least partially impedes, blocks, or redirects and/or modifies the velocity of fluid flow within the scroll, the outlet restriction  67  can at least partially prevent or reduce fluid vortices  505  within the scroll  30 . 
     Some embodiments can include other features designed to change, or otherwise guide the flow of fluid within the scroll  30 . In some embodiments, one or more structures can be included in the scroll  30  to change the flow of a fluid prior to contact with the discharge grid  65 . For example,  FIGS. 1A-D  show perspective views of a scroll assembly  25  according to one embodiment of the invention, and  FIGS. 2A-C  shows perspective views of a scroll assembly  25  according to another embodiment of the invention. In some embodiments, one or more structures as illustrated in  FIGS. 1A-D  and  2 A-C can reduce the noise emitted by the flow of fluid within the scroll  30  either alone, or in combination with the discharge grid  65  including the outlet restriction  67 . 
     As shown in  FIG. 3A , in one embodiment of the invention, a scroll  30  can include a scroll housing  31  comprising an inner scroll surface  44  and an outer surface  42 , and can include a scroll crescent  300 . Some embodiments include at least one scroll crescent  300  located within the scroll  30  substantially integral with the inner scroll surface  44  (for example, see  300  in  FIG. 1B, 2C, 3A-3B ). In other embodiments, the scroll  30  can include at least one scroll crescent  305  substantially adjacent to the inner scroll surface  44  as a discrete component coupled to the scroll  30  (for example, see the scroll crescent  305  in  FIGS. 1A and 3C ). As shown in  FIG. 3D , in some embodiments, the scroll crescent  305  includes studs  307 , and the scroll  30  includes holes  307   a . In some embodiments, the scroll crescent  305  is coupled to the scroll  30  by inserting the studs  307  into the holes  307  as depicted by the assembly view shown in  FIG. 3D . Further, in some embodiments, after the studs have been inserted into the holes  307 , push-nuts  307   b  are pushed over the studs  307  to prevent the scroll crescent  305  from moving or rattling. 
     In some embodiments, the scroll crescent  300 ,  305  is positioned within the scroll  30  so that the first crescent end  320  and the second crescent end  325  are substantially within a quadrant  350  at least partially diagonally opposite a discharge out  35  of the scroll  30 . For example, as shown in  FIG. 3C , in some embodiments, the scroll crescent  305  (and equally applying to the scroll crescent  300  shown in  FIG. 3B ) can be substantially within the quadrant  350  of the scroll housing  31 . As shown, the quadrant  350  is substantially diagonally opposite a discharge outlet  35 . In some embodiments, the first crescent end and the second crescent may extend to encompass about 90 degrees of the quadrant  350 , whereas in other embodiments, the first crescent end and the second crescent may extend to less than 90 degrees of the quadrant, but may be positioned anywhere within the quadrant  350 . Moreover, as shown in  FIGS. 3A and 3C , the scroll crescent be positioned substantially within the scroll  30  so that the first crescent end  320  is substantially 80° or more from the first wall  45   a  of the inner scroll surface  44 , and the second crescent end  325  is substantially 170° or less from the first wall  45   a  of the inner scroll surface  44 . In some other embodiments, the first crescent end  320  can be positioned substantially at 90° from the first wall  45   a  of the inner scroll surface  44 , and the second crescent end can be positioned 180° from the first wall  45   a  of the inner scroll surface  44 . 
     In some embodiments, the scroll crescent  300 ,  305  may be formed from any material that can be readily shaped, including, but not limited to, polymers, polymer-composites, metal, ceramic, or wood, or paper-based composite or laminate, or metals. In some embodiments, the use of injection-molded or thermo-formed polymeric materials conveniently allows the scroll crescent  300  to be integrally formed with the scroll housing  31 . In other embodiments, one or more thermosetting polymer precursors may be used with a thermo-molding or other molding technology of the scroll housing  31  with scroll crescent  300 . In some further embodiments, the scroll crescent  305  can be formed as a discrete component and then later attached to the scroll  30 . Some embodiments include a scroll crescent  305  formed from substantially the same material as the scroll housing  31 . In some embodiments, the scroll crescent  305  may be formed from polymers, polymer-composites, metal, ceramic, or wood, or paper-based composite or laminate, or metals. In some embodiments, the scroll crescent  305  can be injection-molded or thermo-formed, thermo-molding or otherwise formed separately from the formation of the scroll  30 , and later secured to the inner scroll surface  44  of the scroll housing  31 . 
     As shown in  FIGS. 3A-3C , some embodiments include a scroll crescent  300 ,  305  including a first crescent end  320  and a second crescent end  325 . In some embodiments, the first crescent end  320  and the second crescent end  325 , are coupled to the inner scroll surface  44  of the scroll housing  31 . Some embodiments include a scroll crescent  300 ,  305  that includes a substantially incurvated surface  310 , and a substantially convex surface  315  coupled to the inner surface  44  of the scroll housing  31 . In some embodiments, the substantially convex surface  315  is coupled to the first crescent end  320 , the second crescent end  325 , and the substantially incurvated surface  310 . 
     Some embodiments can include some other features designed to change, or otherwise guide the flow of fluid within the scroll  30 . For example, in some embodiments, one or more structures can be included in the scroll  30  to change the flow of a fluid during exit from the scroll  30  through the discharge outlet  35 . In some embodiments, these features can reduce the noise emitted by the ventilation assembly  10  as it leaves the scroll  30  either alone, or in combination with the other features within the scroll  30 , such as the scroll crescent  300 ,  305 . 
     In some embodiments, as fluid flows within the scroll  30  and approaches the outlet  35 , one or more fins  70 ,  80 ,  90 ,  100  of the discharge grid  65  can at least partially straighten the air and just prior to discharge from the scroll  30  through the outlet  35 . For example, as detailed in  FIGS. 4A-4C  showing various perspective views of a discharge grid  65  according to one embodiment of the invention, some embodiments can include a plurality of vertical fins  70 ,  80  and a plurality of horizontal fins  90 ,  100 . In some embodiments, the coupling of the plurality of vertical fins  70 , 80  and a plurality of horizontal fins  90 ,  100  can create at least one aperture  110 . 
     As described earlier, in some embodiments of the invention, a base wall  170  is coupled to the main wall  150  and the restriction wall  130 . In some embodiments, the first end  170   a  of the base wall  170  is coupled with the second end  150   b  at the second surface  150   d  of the main wall  150 , and the bottom base edge  170   d  is coupled with the restriction wall  130 . Some embodiments include the first vertical fin  80  which includes a first end  82   a  and a second end  82   b . In some further embodiments, the second end  170   b  of the base wall  170  is also coupled to the first vertical fin  80  second end  82   b.    
     Some embodiments include a plurality of horizontal fins  90 ,  100 . As shown in  FIGS. 4A-4B , in some embodiments, the discharge grid  65  includes a plurality of horizontal fins  90 ,  100 . Some embodiments include at least one the plurality of horizontal fins  90 ,  100  coupled to the second surface  150   d  of the main wall  150  and an inner surface  130   a  of the restriction wall and the first vertical fin  80 . Some embodiments include a first horizontal fin  90  and a second horizontal fin  100 . Some embodiments can include additional horizontal fins (not shown) substantially identical in structure to horizontal fins  90 ,  100 . In some embodiments, any additional horizontal fins can be spaced substantially similarly to the horizontal fins  90 ,  100 . In some other embodiments, any additional horizontal fins can be spaced substantially differently to the horizontal fins  90 , 100 . 
     In some embodiments, the first horizontal fin  90  can include a first end  95 , a second end  97 , a top edge  94  and a bottom edge  92 . In some embodiments, the second end  97  can be coupled to the second surface  150   d  of the main wall  150 . In some further embodiments, the bottom edge  92  can be coupled to the inner surface  130   a  of the restriction wall  130 . In some further embodiments, the first horizontal fin  90  can couple with the first vertical fin  80 . In some further embodiments, the first horizontal fin  90  can couple with a second vertical fin  70 . In other embodiments, the first horizontal fin  90  can couple with at least one other vertical fin (not shown). Some embodiments can include additional horizontal fins. For example, some embodiments include a second horizontal fin  100 . 
     In some embodiments, the second horizontal fin  100  can include a first end  105 , a second end  107 , a top edge  104  and a bottom edge  102 . In some embodiments, the second end  107  can be coupled to the second surface  150   d  of the main wall  150 . In some further embodiments, the bottom edge  102  can be coupled to the inner surface  130   a  of the restriction wall  130 . In some further embodiments, the second horizontal fin  100  can couple with the first vertical fin  80 . In some further embodiments, the second horizontal fin  100  can couple with a second vertical fin  70 . In other embodiments, the horizontal fin  100  can couple with at least one other vertical fin (not shown). 
     As described and shown in  FIGS. 4A-4C , at least one of the plurality of horizontal fins  90 , 100  can couple with the main wall  150  and the outlet restriction  67  to couple with at least one other vertical fin (at least vertical fins  80  or  70 ), and by doing so, can form at least one aperture  110 . Furthermore, as shown in  FIGS. 1A-1D, 2A-2C, and 3B , in some embodiments, when the discharge grid is coupled with the scroll  30 , further apertures  110  can be form as a result of coupling at least one of the plurality of vertical fins  70 ,  80  and at least one of the plurality of horizontal fins  90 ,  100  with one or more surfaces of the scroll  30 . Moreover, as shown, in some embodiments, the coupling of the discharge grid  65  with the scroll housing  31  can for a plurality of apertures  110 . In some embodiments, at least one of the plurality of apertures  110  can at least partially guide a flow of fluid emerging from the scroll  30  through the discharge outlet  35 . 
     Some embodiments include further features designed to change, or otherwise guide the flow of fluid within the scroll  30 . For example, in some embodiments, one or more structures can be included in the scroll  30  to change the flow of a fluid during exit from the scroll  30  through the discharge outlet  35 . For example, as shown in  FIGS. 4A-4C , in some embodiments one or more of the at least one of the plurality of vertical fins  70 ,  80  and at least one of the plurality of horizontal fins  90 ,  100  can include a flared surface. For example, as shown in  FIG. 4B , some embodiments include a first horizontal fin  90  including a flared surface  93 . In some embodiments, the flared surface  93  includes a flare bottom  96   a  with a flare bottom length  95   a  and a flare top  96   b  with a flared top length  95   b . In some embodiments, the flared surface  93  includes a flare bottom  96   a  with a flare bottom length  95   a  that comprises a surface that is at least partially curved. For example, in some embodiments, the flare bottom  96   a  includes a flare bottom length  95   a  that comprises a substantially rounded surface. In some other embodiments, the flared surface  93  includes a flare top  96   b  with a flare top length  95   b  that comprises a surface that is at least partially curved. For example, in some embodiments, the flare top  96   b  includes a flare top length  95   b  that comprises a substantially rounded surface. In some embodiments, one or more of the curved surfaces of flare top  96   b  or flare bottom  96   a  can at least partially direct, or otherwise modify a flow of fluid emerging from the scroll  30  through the discharge outlet  35 . 
     Some embodiments include further features designed to change, or otherwise guide the flow of fluid within the scroll  30 . For example, as shown in  FIG. 4B  and  FIG. 5 , some embodiments include a second horizontal fin  100  including a flared surface  103 . In some embodiments, the flared surface  103  includes a flare bottom  106   a  with a flare bottom length  105   a  and a flare top  106   b  with a flared top length  105   b . In some embodiments, the flared surface  103  includes a flare bottom  106   a  with a flare bottom length  105   a  that comprises a surface that is at least partially curved. For example, in some embodiments, the flare bottom  106   a  includes a flare bottom length  105   a  that comprises a substantially rounded surface. In some other embodiments, the flared surface  103  includes a flare top  106   b  with a flare top length  105   b  that comprises a surface that is at least partially curved. For example, in some embodiments, the flare top  106   b  includes a flare top length  105   b  that comprises a substantially rounded surface. In some embodiments, one or more of the curved surfaces of flare top  106   b  or flare bottom  106   a  can at least partially direct, or otherwise modify a flow of fluid emerging from the scroll  30  through the discharge outlet  35 . 
     Some embodiments include further features designed to change, or otherwise guide the flow of fluid within the scroll  30 . For example, in some embodiments, one or more structures can be included in the scroll  30  to change the flow of a fluid during exit from the scroll  30  through the discharge outlet  35 . For example, as shown in  FIGS. 4A-4C , in some embodiments one or more of the at least one of the plurality of vertical fins  70 ,  80  can include a flared surface. For example, as shown, some embodiments include a first vertical fin  80  including a flared surface  83 . In some embodiments, the flared surface  83  includes a flare bottom  86   a  with a flare bottom length  85   a  and a flare top  86   b  with a flared top length  85   b . In some embodiments, the flared surface  83  includes a flare bottom  86   a  with a flare bottom length  85   a  that comprises a surface that is at least partially curved. For example, in some embodiments, the flare bottom  86   a  includes a flare bottom length  85   a  that comprises a substantially rounded surface. In some other embodiments, the flared surface  83  includes a flare top  86   b  with a flare top length  85   b  that comprises a surface that is at least partially curved. For example, in some embodiments, the flare top  86   b  includes a flare top length  85   b  that comprises a substantially rounded surface. In some embodiments, one or more of the curved surfaces of flare top  86   b  or flare bottom  86   a  can at least partially direct, or otherwise modify a flow of fluid emerging from the scroll  30  through the discharge outlet  35 . 
     Some embodiments include further features designed to change, or otherwise guide the flow of fluid within the scroll  30 . For example, in some embodiments, one or more structures can be included in the scroll  30  to change the flow of a fluid during exit from the scroll  30  through the discharge outlet  35 . For example, as shown in  FIGS. 4A-4C , in some embodiments one or more of the at least one of the plurality of vertical fins  70 ,  80  can include a flared surface. For example, as shown, some embodiments include a second vertical fin  70  including a flared surface  73 . In some embodiments, the flared surface  73  includes a flare bottom  76   a  with a flare bottom length  75   a  and a flare top  76   b  with a flared top length  75   b . In some embodiments, the flared surface  73  includes a flare bottom  76   a  with a flare bottom length  75   a  that comprises a surface that is at least partially curved. For example, in some embodiments, the flare bottom  76   a  includes a flare bottom length  75   a  that comprises a substantially rounded surface. In some other embodiments, the flared surface  73  includes a flare top  76   b  with a flare top length  75   b  that comprises a surface that is at least partially curved. For example, in some embodiments, the flare top  76   b  includes a flare top length  75   b  that comprises a substantially rounded surface. In some embodiments, one or more of the curved surfaces of flare top  76   b  or flare bottom  76   a  can at least partially direct, or otherwise modify a flow of fluid emerging from the scroll  30  through the discharge outlet  35 . 
     In some embodiments as shown in  FIGS. 4A-4C , the lengths of the flare bottom lengths  75   a ,  85   a  and flare top lengths  75   b ,  85   b  of the vertical fins  70 ,  80  are substantially equal. In other embodiments, one or more of the flare bottom lengths  75   a ,  85   a  and flare top lengths  75   b ,  85   b  can be substantially unequal (not shown). In some embodiments, as shown in  FIGS. 4A-4C , the flare bottom lengths  95   a ,  105   a  and flare top lengths  95   b ,  105   b  of the horizontal fins  90 ,  100  are substantially unequal. As shown, the flare bottom lengths  95   a ,  105   a  are longer than the flare top lengths  95   b ,  105   b . In some other embodiments, the flare bottom lengths  95   a ,  105   a  may be substantially equal in length to the flare top lengths  95   b ,  105   b  (not shown), whereas in other embodiments, the flare bottom lengths  95   a ,  105   a  may be less than the flare top lengths  95   b ,  105   b  (not shown). 
     As described earlier, in some embodiments, the discharge grid  65  can be formed as a discrete component and assembled with the scroll  30  by coupling to the scroll housing  31 . Some embodiments include one or more features to enable coupling of the discharge grid  65  with the housing  31 . For example,  FIG. 6A  is a partial perspective view of a discharge grid  65  with a base snap tab  177  according to one embodiment of the invention. As shown, the base snap tab  177  is coupled to the base wall  170  adjacent a slot  175  in the top base edge  170   c . Some embodiments can include additional base snap tab  177  and slots  175  as required (not shown). In some embodiments, the discharge grid  65  can be coupled to the scroll  30  by coupling the base snap tab  177  with the scroll housing  31 . For example,  FIG. 6B  is a partial perspective view of a scroll showing a snap-feature receptacle (snap slot  178 ) according to one embodiment of the invention. In some embodiments, the discharge grid  65  is secured to the scroll  30  by coupling the base snap tab  177  with the snap slot  178  (see for example  FIGS. 7A and 7B  showing partial perspective views of a discharge grid  65  assembled into a scroll  30  and scroll housing  31  according to one embodiment of the invention). In some other embodiments, other fasteners can be used in addition to, or in place of the base snap tab  177  and snap slot  178  coupling. 
     Some embodiments include additional features for coupling the discharge grid  65  with the scroll  30 . For example, referring to  FIGS. 8A and 8B  showing top and bottom perspective views of a discharge grid  65  according to one embodiment of the invention, as well as  FIG. 9A-9D  showing various full and partial perspective views of a discharge grid  65  according to one embodiment of the invention, in some embodiments, the discharge grid can include additional edge snaps  200 . As shown, in some embodiments, the main wall  150  can include a flange  160 . In some embodiments, the discharge grid  65  can further include a coupling edge  165  coupled to the flange  160 . In some embodiments, the flange  160  and coupling edge  165  can be coupled to a vertical slot  32  in the scroll housing  31  (see  32  in  FIG. 6B ). For example, as show in  FIGS. 8A-8B and 9A-9B , in some embodiments, the coupling edge  165  can include a plurality of edge snaps  200 , and as depicted in  FIG. 9D , the discharge grid  65  can be at least partially coupled to the scroll housing  31 . 
       FIGS. 9E-9H  illustrates various perspective views of another embodiment of a discharge grid  65  according to another embodiment of the invention. As shown, in some embodiments the discharge grid  65  can include an alternative main wall  155  without a coupled base wall  170 . Moreover, in some embodiments, the main wall  155  can be coupled to an alternative flange  163 . In some embodiments, the flange  163  can include at least one coupling hole  163   a . As shown in  FIG. 1D  and the assembly view of  FIG. 1E , in some embodiments, the discharge grid  65  can be coupled to the scroll  30  using fasteners  63  coupled through the flange  163  and coupling holes  163   a , and through fastener holes  66   b  within the scroll  30 . The example shown in  FIGS. 1D and 1E  provide just one embodiment of a grid  65  coupled to the scroll  30  using two fasteners  63 . In some other embodiments, more or less fasteners  63  may be used with more or less fastener holes  66   b  and coupling holes  163   a . In some embodiments, the coupling holes  163   a  may be placed in other locations on the flange  160  and may be coupled with fastener holes  66   b  positioned corresponding to the fastener holes  66   b.    
       FIG. 10A  illustrates a perspective view of a blower assembly  15  according to one embodiment of the invention, and  FIG. 10B  illustrates a perspective view of a ventilation assembly  10  according to one embodiment of the invention. As described earlier, some embodiments of the ventilation assembly  10  can include various components and devices that can perform different functions. For example, in some embodiments the ventilation assembly  10  can include the blower assembly  15  as shown in  FIG. 10A . In some embodiments, the blower assembly  15  can be substantially housed within the housing  20 , and positioned and anchored to the housing  20  aided by at least one retention feature  34 . In some embodiments, the blower assembly  15  can generally include a motor  52  and a blower wheel  50  positioned substantially within the scroll  30  and mechanically coupled to the motor  52 . In some embodiments, a duct connector assembly  58  can be coupled to the ventilation assembly  10 . For example, as shown in  FIGS. 10B and 10C , in some embodiments, the duct connector assembly  58  is coupled to the housing  20  so as to be generally aligned with the discharge outlet  35  of the scroll  30 .  FIG. 10C  for example illustrates a front perspective view of the ventilation assembly  10  according to one embodiment of the invention where the damper flap  60  has been removed from view. As shown, the discharge grid  65  is positioned within the scroll  30  so as to be capable of directing and/or otherwise influencing a flow of fluid forced from the blower wheel  50  within the scroll  30  through the ventilation orifice  62 . 
     As shown in  FIG. 10B , some embodiments can include a duct connector assembly  58  that includes a moveable damper flap  60  coupled with a ventilation orifice  62 . In some embodiments, the damper flap  60  can control the backflow of a fluid into a ventilation orifice  62  and the blower assembly  15 . In some embodiments, a ventilation assembly  10  that includes a duct connector assembly  58  with a moveable damper flap  60  as shown can be capable of substantially controlling the flow of fluid from a space, such as a room, into the ventilation duct of a building, or structure or space. 
     In some embodiments, the ventilation assembly  10  can be operable to discharge fluid from a space to another location. For example, in some embodiments, when power is provided to the blower assembly  15 , a motor  52  can rotate a blower wheel  50  positioned substantially within the scroll  30 . In some embodiments of the invention as described and illustrated, fluid flow is moved substantially towards the duct connector assembly  58 . In some embodiments, the moveable damper flap  60  coupled with a ventilation orifice  62  will open, allowing fluid to be expelled from the ventilation assembly  10 . In some embodiments, the damper flap  60  can control the backflow of a fluid into the ventilation orifice  62  and the blower assembly  15 . 
     In some embodiments, the ventilation orifice  62  can be capable of substantially controlling the flow of fluid from a space, such as a room, into the ventilation duct of a building, or structure, to an outside location. Furthermore, the duct connector assembly  58  is further capable of substantially controlling the flow of fluid from a space into the ventilation of a duct of a building when the motor  52  is unpowered. For example in some embodiments, the moveable damper flap  60  can at least partially seal, or provide a substantially sealed ventilation orifice  62 . In some embodiments, when the motor  52  is unpowered, the damper flap  60  can at least partially prevent, or substantially prevent, a flow of fluid into the blower assembly  15  when the atmospheric pressure outside the ventilation assembly  10  (i.e. within a vent or duct of a home or other building structure to which the duct connector assembly  58  is fluidly coupled) is higher than the pressure within the space to be ventilated. 
     Some embodiments provide a ventilation assembly  10  that can be installed as a new, original equipment installation in a room or building where none had previously existed. In some other embodiments, the ventilation assembly  10  can replace a pre-existing ventilation system. In some further embodiments, the blower assembly  15  can be installed as a new, or a replacement ventilation system, and in some embodiments, the assembly  15  can replace an existing assembly  15 . In some embodiments, the assembly  15  can be installed in a pre-existing cavity or housing  20  in a room or building in order to substantially reduce the level of noise emitted from the ventilation assembly  10  during operation. In some embodiments, the inclusion of either the discharge grid  65 , or the scroll crescent  300 ,  305 , or both within the ventilation assembly  10  as illustrated in  FIG. 1A-1D, 3A, 3C, 10A, 10B , or  10 C and described earlier, can at least partially reduce the level of noise emitted from the ventilation assembly  10  during operation, and therefore at least partially reduce the level of audible noise emitted from the ventilation assembly  10 . In some embodiments, the ventilation assembly  10  as illustrated in  FIG. 1A-1D, 3A, 3C, 10A, 10B , or  10 C and described earlier can reduce the audible noise emitted from the ventilation assembly  10  and therefore reduce the level of audible noise perceived by one or more individuals within the area to be ventilated, or an adjacent room or space. 
     In some embodiments, the ventilation assembly  10  including discharge grid  65  and scroll crescent  300 , 305  as described earlier and illustrated in various embodiments shown at least in  FIGS. 1A-1D, 2A-2C, 3B-3C, 10A and 10B  can reduce the level of audible noise emitted from the assembly  10 . For example,  FIG. 11  shows a graph  400  of noise level (SONES) as a function of pressure Ps (in.w.g) for a conventional ventilation assembly (plot  410 ) versus the ventilation assembly  10  (plot  415 ) according to one embodiment of the invention. As shown, the ventilation assembly  10  including improvements in accordance with some embodiments herein described provide significant reductions in noise level. 
     As described, some embodiments can include at least one component suitable for modifying a flow of fluid within the scroll assembly  25 , which in some embodiments can include the addition of at least one component that can reduce noise creation with the main housing  20 . By applying computer aided fluid dynamic calculations, it is possible to visualize the fluid velocity profile of a fluid within the ventilation assembly  10 . For example,  FIG. 12A  illustrates a plot of a fluid dynamic simulation  500  showing a velocity profile at a fan exit (for example the discharge outlet  35 ) without fluid flow modifiers. As shown, the fluid dynamic simulation  500  includes substantially variable velocity profiles that include high velocity regions including vortices  505 . Conversely,  FIG. 12B  illustrates a plot of a fluid dynamic simulation  600  showing a velocity profile at a fan exit with fluid flow modifiers. As shown, the fluid dynamic simulation  600  includes a velocity profile with minimal variation. 
     The plot of a fluid dynamic simulation  500  in  FIG. 12A  showing a velocity profile at a fan exit with substantially variable velocity profiles that include high velocity regions including vortices  505  provides an example where high pressure gradients may create fluid-induced noise. As shown, the fluid-induced noise may also create structure borne noise transmitted through the structural elements of the ventilation assembly  10 .  FIG. 12B  illustrates that the inclusion of either the discharge grid  65 , or the scroll crescent  300 , 305 , or both, within the ventilation assembly  10  as illustrated in  FIG. 1A-1D, 2A-2C, 3A, 3C, 10A, 10B , or  10 C and described earlier, can at least partially reduce velocity gradients within the ventilation assembly  10 , and therefore can at least partially reduce the level of noise emitted from the ventilation assembly  10  during operation. 
     It will be appreciated by those skilled in the art that while the invention has been described above in connection with particular embodiments and examples, the invention is not necessarily so limited, and that numerous other embodiments, examples, uses, modifications and departures from the embodiments, examples and uses are intended to be encompassed by the claims attached hereto. The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein. Various features and advantages of the invention are set forth in the following claims.