Patent Publication Number: US-2007101985-A1

Title: Kitchen range hood

Description:
FIELD OF THE INVENTION  
      This invention relates to kitchen range hoods. In particular, this invention relates to the mounting of an exhaust chamber housing within a range hood body and the connection between the two.  
     BACKGROUND OF THE INVENTION  
      Kitchen range hoods are used for venting gases from above a cooking surface. The body of a kitchen range hood typically comprises a top panel, two side panels, a rear panel and a bottom panel to accommodate one or more air intakes and fan grills. The panels are generally joined at their edges by welding and form an enclosure.  
      An exhaust chamber housing is mounted within the hood body. At least one motor and one fan are mounted within the exhaust chamber for venting gases drawn in through the air intake(s) and expelled through an exhaust vent to an exterior location. During the process of venting grease-laden air, grease accumulates on the inside of the exhaust chamber.  
      At its most basic, the exhaust chamber is defined by the top panel of the range hood body and the sides and bottom of the exhaust chamber housing. This exhaust chamber configuration for range hoods is taught in U.S. Pat. Nos. 5,228,428 and 5,537,988.  
      For ease of reference, this type of prior art design is shown in  FIG. 1 . Range hood  100  has a top panel  44  and an exhaust chamber housing  46  connected thereto forming an exhaust chamber  45  within which motor  8  and fan  10  are mounted. The exhaust chamber housing  46  has a peripheral wall  47  terminating in a flange  48  at the top and terminating in a bottom surface  49  at the bottom, the bottom surface having at least one intake opening defined therein. The intake opening in the exhaust chamber housing is aligned with the air intake defined in a bottom panel  14  of the range hood. A grease tray  42  is releasably connectable to the bottom surface  49  to capture any grease that may drain into it from the exhaust housing interior or that may drip from the fan  10  after the motor  8  has been shut off and to help direct the airflow into the exhaust chamber. A grill  16  is connected to the bottom panel  14  to prevent accidental contact with the fan when in operation. Grease within the grease tray  42  having sufficient liquidity drains towards a drain hole at the bottom rear of the grease tray and travels through conduit  43  to external grease receptacle  20  for disposal.  
      The exhaust chamber housing  46  is connected to the top panel  44  of the range hood, preferably by welding flange  48  to top panel  44 . While the welded junction between the exhaust housing  46  and top panel  44  is sufficient from the standpoint of structural connectivity, achieving a suitable seal between the flange  48  and the top panel  44  is difficult. The lack of a sufficient seal results in poor ventilation—with gases to be vented from the exhaust chamber  45  instead passing through the junction between flange  48  and top panel  44  into the range hood interior  41 . This reduces the efficiency of the range hood. In addition, accumulated grease within interior  41  is hard to get at in order to clean the interior. This connection is especially ineffective in those range hoods having cleaning systems where cleaning fluid is injected into the exhaust chamber in order to flush out any accumulated grease. The pressure of the fluid itself and the added force from the spinning fan cause fluid and grease to pass through any openings between the flange  48  and the top panel  44  leaking out into the range hood interior  41  contaminating it.  
      Different designs have been developed in order to overcome the problems associated with an ineffective connection between the exhaust chamber housing and the top panel of the range hood body. One such design is a range hood having a fully enclosed exhaust chamber housing having top, bottom and side surfaces. An example of this type of range hood is disclosed in U.S. Pat. No. 6,732,729. The motor housing of the &#39;729 patent is formed of two halves, a top half and a bottom half. The two halves are joined together in such a fashion that no liquid can pass between the connection. While the range hood of the &#39;729 patent overcomes the problem of undesirable leakage of fluid out of the exhaust chamber, it is more costly to make as it requires increased materials as compared to the exhaust chamber of the prior art range hood shown in  FIG. 1  and takes more time to assemble.  
      A further design is taught in U.S. Pat. No. 6,719,622. In the &#39;722 patent, the range hood (or smoke exhaust structure as it is described therein) has an exhaust chamber formed of two part construction, comprising a first face connected to the hood body and a wind chamber releasably connectable to the first face. The wind chamber has a peripheral wall and a second face (a bottom) opposite the first face. The top edge of the peripheral wall fits into a channel in the first face and the wind chamber is latched to the first face. Once again, the problem of undesirable leakage of fluid between the connection between the top panel of the range hood body and the exhaust chamber is overcome by adding a top surface to the exhaust chamber so as to have a fully enclosed exhaust chamber mounted within the range hood enclosure. As above, this design is more costly to make as it requires increased materials as compared to those range hoods having a “topless” exhaust chamber housing connected directly to the top panel of the range hood.  
      Accordingly, there is an ongoing need for a range hood having an improved connection between the motor housing and the range hood while minimizing the amount of material used.  
      This and other objects of the invention will be better understood by reference to the detailed description of the preferred embodiment which follows.  
     SUMMARY OF THE INVENTION  
      According to the present invention there is provided a kitchen range hood comprising a hood body having a top panel and defining an enclosure and having an exhaust chamber housing mounted within the hood body. The exhaust chamber housing has a peripheral wall terminating in a flange at one end and a bottom surface having at least one intake opening at the opposite end. The flange is connected to the top panel. A pocket is formed between the flange and the top panel, the pocket being filled with a seal.  
      In another aspect, the top panel has a raised portion within which the flange is seated.  
      In another aspect, the flange has a stepped portion defining the pocket. The stepped portion can be located at the outer end of the flange or proximal to the peripheral wall.  
      In another aspect, the flange has a recessed mid-portion defining the pocket.  
      In another aspect, the top panel has a raised portion defining the pocket.  
      The foregoing was intended as a broad summary only and of only some of the aspects of the invention. It was not intended to define the limits or requirements of the invention. Other aspects of the invention will be appreciated by reference to the detailed description of the preferred embodiment and to the claims. 
    
    
     BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT  
      A detailed description of the preferred embodiment will be provided by reference to the drawings thereof and of the prior art, in which:  
       FIG. 1  is a partial cross-sectional view of a kitchen range hood as known in the prior art;  
       FIG. 2  is a partial cross-sectional view of a kitchen range hood according to a preferred embodiment of the invention;  
       FIG. 3  is a cross-sectional view of the connection between the exhaust chamber housing and range hood body shown in  FIG. 2  marked as  3 - 3 ;  
       FIG. 3A  is an exploded cross-sectional view of the connection shown in  FIG. 3 ;  
       FIG. 3B  is a cross-sectional view of the connection shown in  FIG. 3  also showing the insertion of sealant;  
       FIG. 4  is a cross-sectional view of an alternative embodiment of the connection between the exhaust chamber housing and range hood body;  
       FIG. 5  is a cross-sectional view of a further alternative embodiment of the connection;  
       FIG. 6  is a cross-sectional view of a further alternative embodiment of the connection;  
       FIG. 7  is a cross-sectional view of a further alternative embodiment of the connection;  
       FIG. 8  is a cross-sectional view of a further alternative embodiment of the connection;  
       FIG. 9  is a cross-sectional view of a further alternative embodiment of the connection;  
       FIG. 10  is a cross-sectional view of a further alternative embodiment of the connection;  
       FIG. 11  is a cross-sectional view of a further alternative embodiment of the connection;  
       FIG. 12  is a cross-sectional view of a further alternative embodiment of the connection; and  
       FIG. 13  is a cross-sectional view of a further alternative embodiment of the connection. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      The preferred embodiment of a range hood  2  according to the invention is shown in  FIG. 2 . Range hood  2  has a range hood body having a top panel  4 , a bottom panel  14  and a front, rear and sides forming an enclosure within which an exhaust chamber housing  6  is mounted. The connection between the exhaust chamber housing  6  and the top panel  4  will be described in greater detail below.  
      The exhaust chamber housing  6  and top panel  4  define an exhaust chamber  30  within which at least one motor  8  and fan  10  are mounted. The exhaust chamber housing has a perimeter side wall  7  terminating in an outwardly extending flange  5  at the top and terminating in a bottom surface  9  having at least one air intake opening defined therein. The intake opening in the exhaust chamber housing is aligned with the air intake defined in the bottom panel  14  of the range hood. A grease tray  12  is releasably connectable to the bottom surface  9  to capture any grease that may drip from the fan  10  after the motor  8  has been shut off and to improve air flow into the exhaust chamber through fan  8 . A grill  16  is connected to the bottom panel  14  to prevent accidental contact with the fan when in operation. Grease within the exhaust chamber housing interior having sufficient liquidity drains towards a drain hole (not shown) at the bottom rear of the exhaust chamber housing and travels through conduit  18  to external grease receptacle  20  for disposal.  
      Referring now to  FIG. 3 , the connection between the exhaust chamber housing  6  and the top panel  4  will now be described in greater detail. Top panel  4  has a raised portion  22 , preferably from pressing and/or machining, forming a recess  21  on the inner surface of top panel  4  as shown in  FIG. 3A . Raised portion  22  is sized and shaped to correspond to flange  5  of the exhaust chamber housing  6 . Flange  5  of the exhaust chamber housing  6  is dimensioned to fit within the recess  21  formed by raised portion  22 . Flange  5  extends substantially perpendicular to wall  7  and has a downwardly stepped end-portion  26  forming a step  25 . When flange  5  is seated in recess  21 , a pocket  70  is formed between downwardly stepped end-portion  26  and top panel  4 .  
      An o-ring  28  (suitably sized and dimensioned and adapted to be fitted in a potentially non-circular pocket, the exhaust chamber typically having a  FIG. 8  shape when viewed from above) or other suitable seal is placed in step  25  and is compressed in pocket  70  when flange  5  is seated in the recess  21  so as to form a tight seal. Preferably, a gap  32  is present between the outer edge  36  of the flange  5  and the bottom outer edge  34  of the raised portion  22  of top panel  4  providing an opening to the pocket  70 . The gap is sized so as to be sufficiently small that the o-ring cannot fit through, but so that sealant can be injected through the gap in addition to, or as an alternative to, the o-ring.  FIG. 3B  shows silicone sealant  27  being injected through gap  32  into the pocket  70  formed by step  25  between stepped end-portion  26  and raised portion  22 . The silicone sealant  27  is injected through gap  32  via a tube of sealant  29 .  
      Flange  5  is connected to top panel  4 , preferably by welding. The welding of the connection according to the invention is preferably performed by a form of spot welding as is known in the art. A broad, flat electrode is used for the top of the connection, namely the raised portion  22  of the top panel  4  that overlies flange  5 , while a point electrode is used on the bottom (hidden) surface of the connection. The use of a broad flat electrode on the top surface acts to distribute the current across the surface of the connection, while the point electrode concentrates the current. Preferably any silicone or other sealant to be used is injected after welding of the exhaust chamber housing  6  to the top panel  4 .  
      By machining the top panel  4  to form raised portion  22 , the structural rigidity of the top panel is increased. In addition, because raised portion  22  defines the recess  21  within which flange  5  is seated, it provides an easy reference for the initial placement of the exhaust chamber housing against top surface  4  during the manufacturing process. The seal provided by the o-ring  28  and/or sealant prevents the escape of any grease-laden gases, or cleaning fluid should it be injected into the exhaust chamber. Because the gap  32  is located on the exterior of the exhaust chamber housing  6 , it provides easier access for the insertion of sealant.  
      Alternative connections between the exhaust chamber housing and the top panel of the range hood are shown in  FIGS. 4-13 . Identical reference numbers have been used to refer to those portions of the alternative embodiments identical to the preferred embodiment described above. In particular, reference numeral  70  has been used in each figure to refer to the pocket formed between the exhaust chamber housing and the top panel.  
      In the alternative embodiment shown in  FIG. 4 , exhaust housing  106  terminates in a flange  110  having a stepped portion  108 . The stepped portion  108  forms the pocket  70  within which the seal is seated when flange  110  is connected to raised portion  22  of top panel  4 . The seal may take the form of an o-ring  28 , silicone sealant, or another suitable sealing material. Preferably, a gap  112  is present between top inner edge  109  of the exhaust housing  106  and the bottom inner edge  23  of the raised portion  22  of top panel  4  providing an opening to pocket  70 . The gap is sized so as to be sufficiently small that the o-ring cannot fit through, but so that sealant can be injected through the gap in addition to, or as an alternative to, the o-ring. While providing a suitable seal for preventing the leakage of grease-laden gases and fluids, placement of the gap  112  in the interior of the exhaust chamber housing  106  makes it more difficult to access for the insertion of sealant, should that be desired.  
      In the alternative embodiment shown in  FIG. 5 , flange  205  of exhaust chamber housing  206  extends substantially perpendicular to wall  207 , has a recessed mid-portion  226  forming a channel  229 , and terminates in a substantially horizontal end  224 . An o-ring  28  or other suitable seal is placed in the pocket  70  formed by channel  229  of recessed mid-portion  226  and top panel  4 . The o-ring  28  is compressed in pocket  70  when flange  205  is seated in the recess  21  formed by raised portion  22  thereby forming a tight seal. Flange  205  is connected to top panel  4 , preferably by welding on either or both sides of recessed mid-portion  226 .  
      In the alternative embodiment shown in  FIG. 6 , top panel  44  is substantially horizontal in the area of the connection with the exhaust chamber housing  206 . Exhaust housing  206  has a flange  205  having recessed mid-portion  226  and substantially horizontal end portion  224 . O-ring  28  (or other suitable sealing material) is seated in the pocket  70  formed by recessed mid-portion  226  and top panel  44 . The o-ring  28  is compressed to form a seal when flange  205  is connected to top panel  44 .  
      In the alternative embodiment shown in  FIG. 7 , top panel  54  has a raised portion  56  forming a pocket  70  within which an o-ring  28  may be seated. The flange  48  of the exhaust housing  46  is connected to top panel  54  so as to seal o-ring  28  within the pocket  70  between flange  48  and the raised portion  56  of top panel  54 . Preferably, flange  48  is connected to top panel  54  by welding on either or both sides of raised portion  56 .  
      In the alternative embodiment shown in  FIG. 8 , top panel  154  has a raised portion  156 . Exhaust chamber housing  146  has a flange  148 . When flange  148  is connected to top panel  154 , a pocket  70  is formed within which an o-ring  28  or other suitable seal may be seated. Flange  148  and raised portion  156  are sized and dimensioned such that a gap  142  is present as between the outer end  149  of flange  148  and the bottom outer edge  134  of the raised portion  156  of top panel  154  providing an opening to pocket  70 . The gap  142  is sized so as to be sufficiently small that the o-ring cannot fit through, but so that sealant can be injected through the gap in addition to, or as an alternative to, the o-ring.  
      In the alternative embodiment shown in  FIG. 9 , top panel  44  is substantially horizontal in the area of the connection with the exhaust chamber housing  6 . The downwardly stepped end-portion  26  of flange  5  forms a pocket  70  when flange  5  is connected to top panel  44 . An o-ring, silicone sealant or other suitable seal may be positioned in pocket  70  so as to form a seal between exhaust housing  6  and top panel  44 .  
      In the alternative embodiment shown in  FIG. 10 , top panel  44  is substantially horizontal in the area of the connection with the exhaust chamber housing  106 . Exhaust housing  106  terminates in flange  110  having stepped portion  108 . The stepped portion  108  forms the pocket  70  within which the seal is seated when flange  110  is connected to top panel  44 . Preferably, the seal will take the form of a silicone sealant or other suitable sealant material injected into the pocket  70 .  
      In the alternative embodiment shown in  FIG. 11 , top panel  154  has raised portion  156 , which, in conjunction with flange  148  of exhaust chamber housing  146  defines pocket  70 , within which an o-ring  28  or other suitable seal may be seated. In this embodiment, flange  148  and raised portion  156  are sized and dimensioned such that a gap  242  is present as between the inner edge  144  of flange  148  and the bottom inner edge  140  of the raised portion  156  of top panel  154 , the gap  242  providing an opening to pocket  70 . The gap  242  is sized so as to be sufficiently small that an o-ring cannot fit through, but so that sealant can be injected through the gap  242  in addition to, or as an alternative to, the o-ring.  
      In the alternative embodiment shown in  FIG. 12 , top panel  60  has a first raised portion  62 , a recessed portion  64  in the shape of a “V” and a second raised portion  74 . Exhaust housing  66  has a flange  69  having a first portion  68 , a recessed portion  70  in the shape of a “V” and a second portion  72 . Flange  69  is sized and dimensioned to correspond to the contour defined by the first and second raised portions  62 ,  74  and the recessed portion  64 . Preferably, flange  69  is welded to top panel  60  on either side of the recessed “V” portion. Top panel  60  and flange  69  can be shaped either before or after they are welded together by pressing the metal panels. The sharply pressed “V” portion acts as a barrier to grease laden gases, preventing grease (and other liquids, such as cleaning fluid) from getting into the range hood interior.  
      In the alternative embodiment shown in  FIG. 13 , an additional “V” has been pressed into the top panel  80  of the range hood body and the exhaust chamber housing  90 . Top panel  80  has a raised portion  88  having two recessed portions  82  and  86 , each recessed portion being substantially “V” shaped. Preferably the “V”-shaped recesses are adjacent to one another, meeting at peak  84 . Exhaust chamber housing  90  has a flange  99  shaped to correspond to the raised portion  88  of the top panel. Flange  99  has a first “V”-shaped recess  92  corresponding to recess  82 , and a second “V”-shaped recess  96  corresponding to recess  86 , with peak  94  corresponding to peak  84 . Welding of the flange  99  to the top panel  80  is preferably completed with the horizontal portion of the flange referred to with reference numeral  98 . Top panel  80  and flange  99  can be shaped either before or after they are welded together by pressing of the metal panels. The sharply pressed “V” portions act as a barrier to grease laden gases, preventing grease (and other liquids, such as cleaning fluid) from getting into the range hood interior.  
      The embodiments of the invention provide a seal as between the top panel of the range hood body and the exhaust chamber housing, thereby preventing the escape of grease-laden gases and fluids. Because the top panel forms the top of the exhaust chamber, the materials used are minimized.  
      The above description has been intended to illustrate the preferred and alternative embodiments of the invention. It will be appreciated that modifications and adaptations to such embodiments may be practiced without departing from the scope of the invention, such scope being most properly defined by reference to this specification as a whole and to the following claims.