Patent Publication Number: US-6662800-B2

Title: Range hood fan spray dispenser

Description:
FIELD OF THE INVENTION 
     This invention relates to range hoods and more particularly to a spray dispenser for a range hood wherein a cleaning fluid is dispersed against the surfaces of a range hood fan in order to remove any accumulated grease from the fan. 
     BACKGROUND OF THE INVENTION 
     Range hoods are used above cooking surfaces to remove grease, common odors and hazardous gases created during the cooking process. Typically, range hoods have a pair of motors horizontally installed in a motor housing within the hood body. Each motor drives a fan. The fans draw air from the cooking area below and force it through the motor housing to ventilation piping. 
     As the vaporized grease contained in the entrained air travels through the motor housing, some of it condenses on the inside walls of the housing from where the shaping of the walls and floor of the housing directs the grease to a circular grease catcher mounted below each fan opening. Grease catchers are known in the art as illustrated in U.S. Pat. Nos. 6,216,686 B1 and 5,537,988. 
     Grease catchers are also adapted to capture any grease that drips off the fan blades when the motors are turned off. Typically, the grease catcher has radial inner and outer trays with a wall separating them. The wall extends vertically so as to be almost flush with the lower edge of the outer circumference of the fan. In this way air being drawn in by the fans is compelled to enter the motor housing rather than the hood body. The wall therefore acts to control the air currents of the range hood. 
     The grease catchers are usually provided with an inclined base or floor, so as to direct accumulated grease to a hole in the floor. A hose is attached to the hole to convey the grease to a grease receptacle outside the range hood. 
     The motor housing and grease catchers are mounted within the hood body. Openings in the lower surface of the hood body are positioned so as to match those of the motor housing. Typically the lower surface of the hood body is removably fitted into the main hood body. A protective grill is attached to the outside of each opening in the hood body so as to prevent the insertion of body parts when the fan is in operation. 
     Alternatively, as set out in my U.S. and Canadian patent applications, numbers 10/035,116 and 2,365,790 respectively, the motor housing may be adapted to act as a grease catcher itself. In this system, a circular wall defining the motor housing intake openings projects vertically into the motor housing, acting as a barrier to grease accumulated therein. The accumulated grease drains directly from the housing rather than to a grease catcher. Grease trays inserted into the intake openings provide a barrier for proper airflow into the housing and to capture any grease that should happen to drip from the fan. 
     Both of the foregoing designs rely on gravity to cause the accumulated grease to drain out of the range hood. However, gravity is not effective in removing all the grease with the result that some becomes caked on to the interior surfaces, thereby reducing the efficiency of the range hood. The foregoing systems of motor housing and grease catchers therefore require periodic cleaning to remove condensed grease accumulated on the fans, motor housing interior and grease catchers or trays. 
     Attempts have been made to overcome the necessity to manually clean the interior of a range hood exhaust system. It is known in the art to provide a washing fluid under pressure in order to clean the interior of the exhaust system. For example, U.S. Pat. No. 4,259,945 teaches an exhaust system in which a washing fluid under pressure is used to clean the flue and fan. Cleaning of the fan is possible as it is set back in the exhaust duct and is positioned such that fluid sprayed on the fan drains to an external receptacle. Similar washing fluid systems are taught in U.S. Pat. Nos. 3,795,181 and 4,085,735. However, these prior art cleaning systems are specific to their respective range hood/exhaust duct designs. 
     A cleaning system is also known in the art with respect to the range hood having a motor housing as described above. A fluid delivering nozzle is fitted into a hole in the side of the motor housing so as to deliver a spray of washing fluid to clean the interior. This is done while the motors are activated so that the force of the air being drawn into the motor housing forces the sprayed fluid against the interior surfaces of the motor housing and prevents any liquid from passing through the air intakes. However, while this system cleans the interior of the motor housing, it does not clean the fan. 
     It is therefore an object of an embodiment of the present invention to provide a spray dispenser for cleaning a fan in a range hood having a motor housing with at least one fan. 
     Other objects of the invention will be apparent from the description that follows. 
     SUMMARY OF THE INVENTION 
     According to the present invention there is provided a spray dispenser for use in a range hood comprising a motor housing having an interior and containing at least one motor and at least one fan, and a grease tray releasably attachable to the motor housing. The spray dispenser comprises a nozzle, a hose, and at least one source of cleaning fluid located externally to the motor housing. The nozzle is positioned so as to disperse cleaning fluid from the source of cleaning fluid against the fan and into the motor housing interior. 
     In one aspect of the invention, the nozzle and hose are located external to the motor housing. 
     In another aspect of the invention, the grease tray comprises an opening, first, second and third tray walls extending around the opening, a first trough formed between the first and second tray walls, a second trough formed between the second and third tray walls, and at least one drainage hole. Preferably, the nozzle extends through apertures in at least two of said first, second and third tray walls; 
     In another aspect of the invention the nozzle has a drip catcher. Preferably the drip catcher is seated in the first trough. 
     In an alternative embodiment of the invention, the grease tray comprises an opening, first and second tray walls extending around the opening, and a trough formed between the walls. 
     In another aspect of the invention, the nozzle is releasably connectable to the grease tray. 
     In another aspect of the invention, the grease tray further comprises a gap in the first and second tray walls, and is sized such that the nozzle may be positioned within the gap. 
     In another aspect of the invention the motor housing has a lower surface having at least one intake opening and at least one drain hole. The intake opening is defined by a wall depending from the lower surface of the motor housing and projecting into the interior of the enclosure. The tray comprises an opening, first and second tray walls extending around the opening, and a floor between the first and second tray walls. The nozzle is releasably connectable to the tray and the tray is releasably connectable to the intake opening. 
     The present invention is also directed a spray dispenser for use in a range hood generally defining an enclosure and comprising an upper panel and a lower panel, the lower panel having at least one air inlet and having a motor housing and tray. The motor housing is connectable to the range hood within the enclosure of the range hood. The motor housing generally defines a further enclosure and comprises a lower surface having at least one intake opening and at least one drain hole. A wall depending from the lower surface and projecting into the interior of the further enclosure defines the intake opening. The spray dispenser comprises a nozzle, a hose, and at least one source of cleaning fluid located externally to said motor housing. The nozzle being positioned so as to disperse cleaning fluid from the source of cleaning fluid against the fan and into the motor housing interior. 
     In another aspect of the invention, the tray comprises an opening, first and second tray walls extending around the tray opening and a trough formed between the walls; and the tray is releasably connectable to the intake opening; 
     In yet another aspect of the invention, the air inlet is defined by a third wall depending from the lower panel and projecting into the interior of the range hood enclosure. The air inlet and the intake opening are of identical shape, the air inlet being located directly below the intake opening. The tray may be releasably inserted into the air inlet and connected to the intake opening. 
     In another aspect of the invention the tray further comprises a gap in the first and second tray walls. The gap is sized such that the nozzle may be seated within the gap when the tray is inserted into the air inlet and connected to the intake opening. 
     Other aspects of the invention will be appreciated by reference to the detailed description of the preferred embodiment and to the claims that follow. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings wherein: 
     FIG. 1 is a sectional view of a range hood according to the preferred embodiment of the invention with the right hand portion of the figure providing a deeper sectional view than the left hand portion of the figure; 
     FIG. 2 is an exploded sectional view of portions of the range hood of FIG. 1; 
     FIG. 3 is a sectional view of a range hood according to an alternative embodiment of the invention with the right hand portion of the figure providing a deeper sectional view than the left hand portion of the figure; 
     FIG. 4 is an exploded sectional view of portions of the range hood of FIG. 3; 
     FIG. 5 is a sectional view of a further alternative embodiment of a range hood according to the invention with the right hand portion of the figure providing a deeper sectional view than the left hand portion of the figure; 
     FIG. 6 is a top plan view of the grease tray of the range hood of FIG. 5; 
     FIG. 7 is a sectional view of a further alternative embodiment of a range hood according to the invention with the right hand portion of the figure providing a deeper sectional view than the left hand portion of the figure; 
     FIG. 8 is an exploded sectional view of portions of the range hood of FIG.  7   
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The preferred embodiment of a range hood  100  with a spray dispenser according to the invention is illustrated in FIG.  1 . The spray dispenser is connected to a source of cleaning fluid. A pump forces the cleaning fluid to the spray dispenser where it is dispersed against grease coated surfaces of the range hood fans. This will be described in greater detail below by reference to the preferred and alternative embodiments. 
     In the preferred embodiment, the motor housing  110  defines an enclosure and is mountable within a further enclosure formed by the hood body generally indicated by the numeral  102 . The interior of the housing  110  may be coated with a non-stick material so as to facilitate grease removal and is separated into two substantially similar, separate chambers  4 , one of which is visible in FIG.  1 . Each chamber  4  has an intake opening  112  and ventilation hole (not shown). The ventilation holes project through the upper surface of hood body  102  when the housing  110  is attached to the interior of the hood body  102 . 
     A motor  125  is fitted in each chamber  4  of the motor housing  110  and is attached to the inside of the upper surface of the hood body  102 . A fan  120 , of the semi-impeller type, is secured to each of the motors  125  by fan caps  129 , acts to draw grease-laden air into the motor housing  110  and out the ventilation holes. The fans  120  are dimensioned so as to be removable from within the housing  110  through openings  112 . 
     The motor housing  110  acts as an integral grease catcher and includes walls  130  depending and rising vertically from the lower surface of the motor housing in each chamber  4 . An outwardly and downwardly projecting extension or lip  132  depends from wall  130 , so as to form a gap  134  between the lip  132  and wall  130 . Extension  132  may diverge from wall  130  such that gap  134  forms a wedge surface. A tray  140  is dimensioned such that its outer wall  142  may be releasably connected to gap  134 . This is discussed in greater detail below. 
     The lower surfaces of the chambers  4  of the motor housing  110  are each shaped such that any accumulated grease or other liquid is directed by gravity towards their respective drain holes  123  as shown in FIG.  1 . Holes  123  are therefore located at the lowest point of lower surface  118  of the motor housing  110 . As seen in FIG. 1, a drainage hose  127  is attached to each hole  123  (only one is visible). Accumulated liquid travels through drainage hoses  127  by way of gravity to external grease cups  126  (only one of which is shown in FIG.  1 ). Wall  130  acts as a barrier to any liquid that accumulates in the interior of the motor housing, preventing it from dripping through openings  112 . 
     As illustrated in FIGS. 1 and 2, for each chamber  4  the spray dispenser includes a hose  162  connected at one end to nozzle  160  and at the other end to a pump (not shown) through which cleaning fluid is pumped. Preferably nozzle  160  is equipped with a drip catcher  164 . The nozzle  160  is positioned so as to disperse a spray solution against the fans  120  so as to force grease accumulated on the fans  120  into the chambers  4  of the motor housing  110 . Preferably, the nozzle  160  is releasably connectable to a surface of the motor housing  110 . Once nozzle  160  is connected to the motor housing, hose  162  may be releasably attached to the nozzle by way of crip  290  or other means. 
     The tray  140  while also being releasably connectable to housing  110 , also connects to the lower panel  108 , which is removable from the remainder of main hood body  102 . Lower panel  108  has a pair of air inlets  109 , one of which is shown in FIG.  2 . Air inlets  109  are defined by circular vertical walls  101 , which depend, and rise vertically from, lower panel  108 . The circular vertical walls  101  can vary in height between a minimum height and a maximum height. The minimum height is the height at which the circular vertical walls  101  will remain in contact with the tray  140  when it is connected to the housing  110  as described below. The maximum height is the height at which the top of the circular vertical walls  101  abuts the bottom of the nozzle  160  when the lower panel  108  is connected with hood body  102 . 
     Tray  140  has a fan grill  138  and is connected to the range hood  100  by inserting it through intake opening  109  in lower panel  108  and into intake opening  112  in the motor housing  110  until outer wall  142  is firmly in place within gap  134 . Tray  140  may be releasably connected to housing  110  by wedging outer wall  142  into gap  134 . When connecting the tray  140 , it must be positioned so as to line-up gap  148  (shown in FIG. 2) formed in the tray walls  144 ,  142  with nozzle  162  such that the nozzle is seated, preferably tightly, within the gap  148 . When tray  140  is connected to the housing  110 , outer wall  142  is also in contact with lower panel  108  and acts to seal any space that may exist between the housing and the lower panel thereby preventing air from entering into any undesired area within the range hood body  102 . A clip or other form of suitable restraint (not shown) accessible on the outside surface of the range hood is used to hold the tray in place. In this way, lower panel  108  need not be removed in order to access the interior of the motor housing  110 . A user need simply remove the tray in order to access the interior of the housing. 
     Preferably, the nozzles are made of plastic. However, any solid material with suitable characteristics may be used. Drip catcher  164  is preferably made of plastic or rubber and is dimensioned such that when tray  140  is in place, drainage end  166  sits within the confines of trough  146  of the tray  140 . Drip catcher  164  is set at a downward angle, drainage end  166  being lower than the remainder of the drip catcher. Any cleaning fluid dripping from nozzle  160  is caught by drip catcher  164  where it drains into trough  146  where it eventually evaporates or is removed during regular maintenance. 
     It is contemplated that the spray dispenser will be used in conjunction with the cleaning system of the prior art wherein cleaning fluid is sprayed into the motor housing  110  through the sides of the motor housing. 
     An alternative embodiment is shown in FIGS. 3 and 4. Range hood  200  has motor housing  110  within hood body  202 . In this embodiment fan  220  is of the squirrel cage type and is attached to motor  125 . In order to remove grease from the fan  220 , a nozzle  260  is used. At one end nozzle  260  has twin heads  264  for greater dispersion of cleaning fluid against the fan  220 ; however, any number of heads is satisfactory provided there is at least one. One end of a hose  262  is attached to nozzle  260 , while the other end of hose  262  is attached to a pump (not shown). 
     Range hood  200  also has a different tray  240  and lower panel  208  design. In this embodiment, tray  240  has inner wall  244  and concentric outer wall  242 . Inner wall  244  defines an opening. Outer wall  242  is distal from the opening in relation to the inner wall  244 . Outer wall  242  is shaped and dimensioned to fit within gap  134  when tray  240  is connected with housing  110  so that a portion of outer wall  142  is in abutment with wall  130 . Preferably, the diameter of inner wall  244  is smaller than the diameter of lower fan edge  222 . The tray  240  is dimensioned such that when connected with the motor housing  110 , the top of inner wall  244  is just below the level of fan  220 , thereby directing air into the housing  110  by way of the fan  220 . 
     Nozzle  260  may be releasably or permanently attached to tray  240 , for example by connector  268 , such that when the tray is connected to motor housing  110 , hose  260  may then be attached to nozzle  262 . Connection means such as a crip  290  are used to connect hose  262  to one end of nozzle  260 . It is contemplated that other methods of connection would be equally viable. Cleaning fluid is pumped through hose  262  and is dispersed over a wide area by nozzle  260  against fan  220  thereby forcing any accumulated grease into the interior of the motor housing  110 . Because the twin heads  264  are situated overtop of trough  246 , any cleaning fluid that should happen to drip from them will land in tray  240  where it eventually evaporates or is removed during regular maintenance. 
     In order to access the interior of the range hood, one must remove lower panel  208 , which has integrated fan grill  238  to prevent insertion of objects into the fan  220 . 
     A further alternative embodiment of a range hood  300  is shown in FIG.  5 . Enclosed in hood body  302 , motor housing  310  is compartmentalized in a similar fashion to the housing  110  of the preferred embodiment. However, the lower surface  313  of motor housing  310  is shaped such that grease accumulated in the housing interior drains into tray  340 . 
     An integrated fan nozzle  360  passes through apertures in each of walls  342 ,  348  and  344  as shown in FIGS. 5 and 6. Hose  362  attached to a pump (not shown) may be releasably attached to the fan nozzle  362  by way of crip  290 . Cleaning fluid travelling through hose  362  is directed by fan nozzle  360  against the fan  120  thereby forcing any accumulated grease into the interior of the motor housing where it then drains down to tray  340 . Drip catcher  364  acts to prevent any cleaning fluid that drips from nozzle  360  from falling on the cooking surface below, instead directing any cleaning fluid to the confines of the inner trough  345 . As shown in FIG. 7, channel  395  travels from inner trough  345  through wall  348  and outer trough  346  to wall  342  where it combines with drainage hole  380 . Drainage hole  382  is located on the opposite side of a partition wall  390 , thereby allowing grease on that side of the tray to drain out of the range hood. Grease and used cleaning fluid drains through drainage holes  380  and  382  through hoses  327  (only one is shown) to external grease cups  326  (only one shown). 
     To access the motor housing interior, first lower panel  308  with integrated fan grill  338  must be removed from the remainder of the hood body  302 . Using crips  290 , hose  362  is removed from nozzle  360  before removing tray  340 . 
     As is apparent from the three embodiments described above, the spray dispenser of the present invention may be adapted for various range hood and tray designs. This is shown in FIGS. 7 and 8, where a further alternative embodiment is shown. Motor housing  410  is similar in all respects to motor housing  110  except with respect to its size in relation to the motor  125  and fan  120 . Motor housing  410  is compressed vertically, such that fan  120  sits approximately half in and half out of the motor housing  410  when it is connected to motor  125  by way of fan cap  129 . 
     The tray  440  is similar to that of FIGS. 1 and 2, but is-simply dimensioned differently. Outer wall  444  extends a much greater distance vertically than does inner wall  442 . Nozzle  460  may be releasably or permanently connected to the bottom of tray  440  by connector  468 . Hose  462  may be connected to nozzle  460  by crip  290  and to a pump providing a source of cleaning fluid. 
     Further alternative embodiments of the invention are contemplated by combining different fan types with different motor housing and grease tray designs. 
     The spray dispenser may be activated in one of two ways. First, the range hood may be adapted such that the pump connected to the spray dispenser is automatically activated for a set period of time during range hood use. The duration of activity may be varied, however it preferably lasts for approximately 15 seconds. Alternatively, the pump of the fan cleaner may be activated manually. In this way, if the range hood is subjected to particularly greasy vapour on a given day, the fan cleaner may be activated manually in order to ensure that sufficient cleaning fluid is sprayed against the fans to force off all the accumulated grease. 
     Typically only a very small amount of grease accumulates on a fan as most is dispersed by means of the centripetal force of the rotating fan. However, any grease or liquid that remain on the fan will be forced to the interior of the housing by the cleaning fluid as discussed with respect to the various embodiments above. As a result of the grease being removed from the fan, very little grease accumulates in the trays, and they need only be checked, and cleaned if necessary, during regular maintenance of the range hood. 
     It will be appreciated by those skilled in the art that the preferred and alternative embodiments have been described in some detail but that certain modifications may be practiced without departing from the principles of the invention.