Abstract:
A baffle filter for a ventilator has first and second frames with end and side walls, face to face and releasably attached. First and second baffles are mounted in the first and second frames, parallel and spaced apart. Each baffle has a base and two sides forming a U shaped channel open towards the other frame. The sides of each second baffle are angled towards the first frame and away from each other. The second and first baffles overlap and alternate to define serpentine paths into the filter between two first baffles, into the channel of a second baffle, back between the second baffle and one of those two first baffles, into the channel defined by that first baffle, and out between that second baffle and an adjacent second baffle. The channels of the first baffles extend toward drain holes in an end wall of the first frame.

Description:
RELATED APPLICATION 
       [0001]    This application claims priority to U.S. Provisional Application No. 62/012,611 filed on Jun. 16, 2014, the disclosure of which is incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to ventilator hoods and, more particularly, to an improved baffle assembly for catching grease in a ventilator hood assembly. 
       BACKGROUND 
       [0003]    When cooking on a stove, significant amounts of grease may be released into the air. When a ventilator or extractor fan is used to remove air from above the stove through an exhaust duct, the grease may be drawn into the ventilator system. This may result in a build-up of grease in the exhaust duct, and/or the discharge of grease through an outlet of the exhaust duct, with undesirable effects in either case. 
       SUMMARY 
       [0004]    According to an aspect of the invention, there is provided a baffle filter for a ventilator, comprising a first frame having two end walls and two side walls, a second frame face to face with the first frame and releasably attached to the first frame, the second frame having two end walls and two side walls, a plurality of first baffles, generally parallel to and spaced apart from one another, mounted in the first frame,  each first baffle comprising a base and two sides forming a generally U shape, each first baffle defining a channel open towards the second frame, the first baffles extending substantially parallel to the side walls of the first frame, a plurality of second baffles, generally parallel to one another and to the first baffles and spaced apart from one another, mounted in the second frame, each second baffle comprising a base and two sides, the sides of each second baffle angled towards the first frame and away from each other, each second baffle defining a channel open towards the first frame, the second baffles extending substantially parallel to the side walls of the second frame, the second baffles and the first baffles overlapping and alternating so as to define serpentine air flow paths extending into the filter between two adjacent ones of the first baffles and into the channel defined by one of the second baffles, back between one of the sides of said one of the second baffles and one of the sides of one of said two adjacent ones of the first baffles and into the channel defined by said one of the first baffles, and out of the filter between said one of the second baffles and an adjacent one of the second baffles; and drain holes formed in at least one end wall of the first frame, the channels of the first baffles extending toward the drain holes. 
         [0005]    In an embodiment, the sides of each first baffle may be bent to form proximal portions angled towards the second frame and away from each other and distal portions angled towards the second frame and towards each other. Alternatively, the sides of each first baffle may be curved so that portions nearest the base curve towards the second frame and away from each other and portions furthest from the base curve towards the second frame and towards each other. In an embodiment, the baffle filter further comprises at least one additional baffle, comprising a base joined to a side wall of the first frame or the second frame and one side wall, and defining an additional serpentine flow path with an outermost one of said first baffles and an outermost one of said second baffles. 
         [0006]    In an embodiment, free edges of the sides of the first baffles and free edges of the sides of the second baffles are generally coplanar. 
         [0007]    According to another aspect, a baffle filter assembly for a ventilator comprises a housing defining an opening; and a baffle filter according to any of the mentioned aspects and embodiments. The baffle filter is positioned across the opening with the second frame above the first frame and an end wall having the drain holes lower than an opposite end wall, and a receptacle for flowable materials under the drain holes outside the baffle filter. 
         [0008]    In an embodiment, the receptacle for flowable materials may comprise an elongate trough extending along said end wall, further comprising a transverse member extending across the elongate trough and supporting an end of the baffle filter comprising said end wall. 
         [0009]    In an embodiment, the baffle filter may occupy substantially an entire area of the opening. In an alternative embodiment, there is at least one additional baffle filter according to any of the mentioned aspects and embodiments, and both or all of the filter may then together occupy substantially an entire area of the opening in the housing. 
         [0010]    In an embodiment, the assembly may further comprise a ventilator operative to draw air upwards through the opening in the housing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    For the purpose of illustrating the invention, the drawings show a form of the invention which is presently preferred. However, it should be understood that this invention is not limited to the precise arrangements and instrumentalities shown in the drawings. 
           [0012]      FIG. 1  is a perspective view of a baffle assembly according to the present invention for use in a ventilator hood. 
           [0013]      FIG. 2  is a perspective view of the reverse side of the baffle assembly of  FIG. 1  with an optional charcoal filter kit. 
           [0014]      FIG. 3  is a perspective view of the baffle assembly of  FIG. 1  installed in a ventilator hood. 
           [0015]      FIG. 4  is a perspective view of the baffle assembly of  FIG. 1  disassembled for cleaning. 
           [0016]      FIG. 5A  is a bottom view of the baffle assembly of  FIG. 1 . 
           [0017]      FIG. 5B  is a cross-sectional view of the baffle assembly of  FIG. 5A  taken along line  5 B- 5 B. 
           [0018]      FIG. 5C  is a top view of the baffle assembly of  FIG. 5A . 
           [0019]      FIG. 6A  is a side schematic view of the baffle assembly of  FIG. 1  installed in an embodiment of a ventilator hood assembly. 
           [0020]      FIG. 6B  is a side schematic view of the baffle assembly of  FIG. 6A  in the process of being removed from or installed into the ventilator hood assembly. 
           [0021]      FIG. 7A  is a bottom view of the ventilator hood assembly of  FIG. 6A  with three baffle assemblies of  FIG. 1  mounted adjacent to one another. 
           [0022]      FIG. 7B  is a cross-sectional view of the ventilator hood assembly in  FIG. 7A  taken along line  7 B- 7 B. 
           [0023]      FIG. 8  is an enlarged portion of the cross-section of the baffle assembly of  FIG. 5B  illustrating the airflows and capture of grease. 
           [0024]      FIG. 9A  is a top view of an embodiment of a drainage trough. 
           [0025]      FIG. 9B  is a cross-sectional view of the drainage trough in  FIG. 9A  taken along line  9 B- 9 B. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0026]    Referring to the drawings, an embodiment of a baffle assembly  10  as presently preferred is illustrated. The baffle assembly  10  includes a lower baffle section  12  and an upper baffle section  14  that are removably attached to one another. The lower baffle section  12  includes a frame  16  and a plurality of linear spaced apart lower baffle channels  18  that are secured to the frame  16 , such as through fasteners, welding or brazing. The channels  18  could be removably secured to the frame  16 , such as through the use of clips. The channels  18  have an open side  20  that faces toward the back of the lower baffle section  12  (i.e., to the upper baffle section  14 ). The spacing  22  between the channels  18  defines open areas for air to flow from one side of the lower baffle section to the other as will be discussed in more detail below. In the illustrated embodiment, each lower baffle channel  18  has a base wall  18 A and two curved or bent side walls  18 B extending away from the base wall  18 A so as to form a substantially U-shaped cross section. The lower baffle channel  18  is designed to capture and provide a conduit for grease that is released from the passing airstream. The curved or bent side walls  18 B are configured to facilitate insertion and removal of the baffle assembly by providing a comfortable contour for a user to grasp. Since during use the lower baffle channels  18  will likely have some grease or other captured contaminants on their outer surface, providing a contoured outer surface of the channel  18  permits a user to grasp the channel firmly when removing the baffle assembly  10  without risk of being cut. 
         [0027]    The frame  16  includes sidewalls  16 A preferably on all four sides of the lower baffle section  12 . At least one drainage hole  19  is formed in at least one sidewall  16 A so as to permit drainage from the lower baffle channels  18 . More preferably there is a drainage hole  19  associated with each lower baffle channel  18  and in close proximity to the base wall  18 A. 
         [0028]    The upper baffle section  14  is similar to the lower baffle assembly  12  and includes a frame  24  and a plurality of linear spaced apart upper baffle channels  26  that are secured to the frame  24 , such as through fasteners, welding or brazing, or could be removable attached. Each upper baffle channel  26  has a base wall  26 A with one or more sloping side walls  26 B extending outwardly away from the base wall so as to form a substantially straight walled U-shaped channel. It is noted that the baffle channels closest to the frame  24  may form a portion of a U-shaped channel the other side of which is formed by the frame, as shown in  FIG. 5B . The open side  28  of the channel faces toward the front of the upper baffle section  14  (i.e., toward the lower baffle section  12 ). The spacing  30  between the channels defines open areas for air to flow from one side of the baffle section to the other for directing the air flow as will be discussed below. 
         [0029]    The frame  24  includes sidewalls  24 A preferably on all four sides of the upper baffle section  14 . At least one drainage hole  27  is formed in at least one sidewall  24 A so as to permit drainage from the upper baffle channels  26 . More preferably, there is a drainage hole  27  associated with each upper baffle channel  26  and away from the base  26 A as shown in  FIG. 5B . 
         [0030]    The mounting and spacing of the upper baffle channels  26  to the frame  24  is such that that open side  28  of each upper baffle channel  26  is positioned so as to be aligned with the spacing  22  between the lower baffle channels  18  in the lower baffle section  12 . This configuration results in the spacings between the lower and upper baffle sections defining a serpentine flow path though the baffle assembly  10  as illustrated by the arrows in  FIG. 5B . 
         [0031]    As shown in  FIG. 2 , an optional charcoal filter assembly  32  may be included. the filter assembly  32  includes a bracket  34  that is attached to the rear face (the top) of the upper baffle section  14 . The bracket  34  is designed to removably secure a charcoal filter  36  to the top (exhaust side) of the upper baffle section  14 . In the illustrated embodiment, the bracket includes three flanges that define an open slot on the side for the charcoal filter to slide into. The charcoal filter  36  includes a charcoal filter media  37  mounted within a metal or plastic frame  38 . The bracket  34  can be attached to the upper baffle section  14  through any conventional means, including through use of one or more screws. 
         [0032]    As discussed above, the lower baffle section and upper baffle section are removably attached to one another. The removable attachment can be through various mechanisms, such as thumb screws, quarter-turn fasteners, clamps, for example, so as to permit a user to separate the two sections  12 ,  14  without the need for tools. It is also contemplated that one of the sections  12 ,  14  may include a bracket similar to the charcoal filter bracket  34  which is sized to receive the other section  12 ,  14 , thus permitting one section to be slid into engagement with the other. The separation of the baffle sections  12 ,  14  permits the two baffle sections to be easily cleaned.  FIG. 4  illustrates the baffles separated from one another. Preferably the baffle sections  12 ,  14  are made from a material that is capable of withstanding moisture and heat without deteriorating, such as stainless steel or high temperature plastic. The material is preferably selected to be dishwasher safe so that the separate sections can be placed into a dishwasher for cleaning. 
         [0033]    Referring to  FIGS. 3 ,  7 A and  7 B, the baffle assembly  10  is shown mounted to the bottom of a ventilator hood assembly  40 . The ventilator hood assembly  40  includes an exhaust duct  42 , a blower assembly  44  and a hood  46 . In the illustrated embodiment there are preferably multiple baffle assemblies  10  mounted to the hood  46  adjacent to one another. 
         [0034]    Referring to  FIGS. 6A and 6B , the mounting of the baffle assembly  10  to the cooktop hood  46  is shown in one embodiment. The hood  46  includes a housing  50  with a rear bracket  52  and a front bracket  54 . The front bracket  54  includes a flange  56  that extends upward into the housing  50  and terminates at a lip  58 . The rear bracket  52  also has a vertical flange  60  that extends into the housing  50 . As shown, the upper end of the vertical flange  60  of the rear bracket  52  is located below the upper end of the vertical flange  56  and lip  58  of the front bracket  54 . The vertical flange  60  of the rear bracket  52  is designed to contain one or more removable drainage troughs  62 . 
         [0035]    The removable drainage trough  62  is shown in detail in  FIGS. 9A and 9B . The trough includes a bottom and four sidewalls  62 A for capturing grease and other contaminants. A center rib  63  extends at least partially between the two long sidewalls and is shorter than the sidewalls  62 A. 
         [0036]    The baffle assembly  10  is installed on the hood  46  by inserting a first side edge  47 A of the baffle assembly into the opening on the bottom of the hood  46  as shown, and sliding it upward and forward until a second side edge  47 B of the baffle assembly  10  (opposite from the first side edge  47 A) clears the rear bracket  52  as shown in  FIG. 6B . The second side edge  47 B is then moved upwards until it clears the top of the vertical flange  60  and the top of the sidewall  62 A of the drainage trough  62 . The baffle assembly  10  is then slid backwards until the back edge of the frame  16  of the lower baffle section  12  sits on the center rib  63  of the drainage trough  62 . As should be apparent from the figures, the height difference between the flange  56  and the center rib  63  results in the baffle assembly  10  resting at an angle tilted rearward and downward toward the back of the hood  46 . This angle is designed to cause grease that is captured by the baffle assembly  10  to drain down the lower baffle channels  18  and out of the drainage holes  19 , and down the upper baffle channels  26  and out of the drainage holes  27 . The height of the center rib  63  prevents the flange  60  of the rear bracket  52  and the sidewall  62 A from blocking the drainage of the grease. As shown in  FIG. 7B , the drainage trough  62  extends perpendicular to the orientation of the channels  18  so as to capture all the grease being drained. In the illustrated embodiment, the drainage trough  62  is slightly larger than the width of the lower baffle section  12  of a single baffle assembly  10 , so that the lower baffle section  12  fits between the sidewalls  62 A. As such, if there are multiple baffle assemblies  10  in the hood assembly  40 , then there would be a drainage trough  62  associated with each baffle assembly  10 . However, it is also contemplated that the drainage trough  62  may extend the width of the several or all of the baffle assemblies  10 . By making the drainage trough removable, it can be easily cleaned by the user. 
         [0037]    Referring to  FIG. 8 , as discussed above, the channels in the upper and lower baffle sections are designed to direct and capture grease that is entrapped within the air stream as it is being exhausted. During use, when the motor assembly  44  is activated, a negative pressure (vacuum) is created along the top of the upper baffle section  14 . This causes air from the cooktop to be drawn first through the spacing  22  between the lower baffle channels  18  and into the open side  28  of the upper baffle channels  26 . The grease laden air hits the base  26 A of the upper baffle channel  26  and is then directed to the lower baffle channel  18 , contacting its base  18 A. Due to surface tension and the physical properties of the grease, the grease is retained on bases  26 A and  18 A as the air continues to flow as shown in the figure by the solid arrow. As the grease builds up on channel  26 , gravity and the pressure caused by the flowing air will cause the grease to slide along the side walls  26 B of the upper baffle channel. This is shown by the stippling in  FIG. 8 . The grease will eventually drain down onto the base  18 A of the lower baffle channel  18  where it will collect. As discussed above, the baffle assembly  10  is mounted on an angle in the hood  46 . As such, the grease will flow along the base  18 A of the lower baffle channel  18  to the drainage holes  19 . Once the grease reaches the holes  19 , the grease will drain into the drainage trough  62 . 
         [0038]    In the interests of clarity, the embodiment has been described with reference to an ordinary orientation in use. However, the baffle assembly may be stored and transported in any orientation, and could in some circumstances be used in an orientation other than that described, and terms of orientation should not be interpreted as excluding such other orientations.