Device for the removal of foul air from toilet bowls
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part application of U.S. patent application Ser. No. 612,847 filed May 22, 1984 and entitled &#34;The Valarao Device for the Removal of Foul Air from Toilet Bowls&#34;, now abandoned. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a device for extracting objectionable odors from toilet bowls. 
     BACKGROUND OF THE INVENTION 
     Various odor extracting devices in combination with the toilet per se have been described in the prior art. Most of the systems described involve either drastic modifications on the toilet bowl or the installation of complicated power ventilation systems communicating with the sewage piping system. The majority of the structures are not readily attachable to the existing toilet bowl installation and are not provided with adequate controls against the sewer and gas backups. Further, many devices heretofor found in the prior art do not provide for recirculation and hence blower or fan overheating can occur. 
     SUMMARY OF THE INVENTION 
     There is, therefore, provided in the practice of the present invention, a device and system for a toilet or water closet which is easily installed on a conventional water closet without requiring modifications thereto, which provides for recirculation of ventilated air to prevent the fan from overheating and which is adaptable to many water tank component configurations. 
     Toward this end, the device is adapted to be used with a water closet of the type having a bowl with a rim, a water tank with a cover and a passageway providing communication between the tank and bowl. The passageway communicates with the bowl through a plurality of openings at the bowl rim to provide for a downward cascade when the toilet is flushed. Valve means are provided within the tank for opening and closing the passageway for flushing the toilet into a sewer pipe and for interchanging the water in the bowl. An overflow pipe disposed in the tank drains into the passageway and sewer pipe should the tank be overfilled. The device for use with this conventional water closet includes a power exhaust structure attachable to the water tan top between the tank and its cover. The structure includes a lower lip adapted to seal against the top of the water closet tank terminating opposite the lip at an upper border adapted to sealingly mate with the tank cover. A barrier wall is disposed in the housing to define, in combination with the cover, a closed chamber separated from the interior of the tank by the partition. The barrier wall includes a bore aligned closely about the overflow pipe for the water tank and filter means to pass air from the chamber into the tank while filtering orders therefrom. A portion of the air circulated through the filter means recirculates back to the bore to continuously provide the fan with a supply of air for cooling thereof. The filtered air not recirculating back to the fan is discharged from the structure to atmosphere through an opening preferably embodied as an undercut in the structure&#39;s lip. 
     To provide for arranging the overflow pipe closely adjacent the bore and fan an adjustable adapter is provided which slips over the overflow pipe. Opposite the overflow pipe, the adapter telescopes to be closely arranged relative to the bore and fan to direct air from the passageway and overflow pipe to the fan. The adapter further includes a telescopic dip leg. When the water tank is filled with water the dip leg is submerged whereby said fan draws odors from the passageway through the overflow pipe and adapter for filtering odors therefrom. When the toilet is flused, the water is directed through the passageway to the toilet bowl, the water level on the tank dropping. In that the passageway will be blocked by water, when the water in the tank drops below the dip leg air within the tank is supplied through the dip leg and adapter to the fan making sure that the fan has a continuous supply of circulating air. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features and advantages of the present invention will become appreciated as the same becomes better understood with reference to the specification, claims and drawings wherein: 
     FIG. 1 is a cross-section view of the water closet tank and of the device according to one embodiment of the invention; 
     FIG. 2 is a side section view of the water closet and tank and device of FIG. 1; 
     FIG. 3 is a bottom view of the device according to the embodiment of FIG. 1; 
     FIG. 4 is a front section view of yet another embodiment of the device according to the present invention shown mounted on a water closet tank, and 
     FIG. 5 is an exploded view of an adapter for use with the device shown in FIG. 4. 
    
    
     DETAILED DESCRIPTION 
     Referring now in detail to the drawings, FIGS. 1 and 2 illustrate a conventional toilet including a water tank 10 and toilet bowl 12 which incorporates one embodiment of a device 16 according to the present invention. As best shown in FIG. 1, the device 16 is adapted to be placed on top of the water tank 10 and is molded to include a bottom barrier wall 18 the periphery of which has a lip 20 adapted to closely mate with the top of the tank 10. Upstanding side walls 22 extend from the barrier wall 18 to an upper extremity to receive the tank top 24 and cooperate with the barrier wall 18 to define a generally closed upper chamber 26. The top 24 is preferably the conventional porcelain top found in most toilets having tanks 10. 
     The toilet bowl 12 includes a plurality of seat rim holes 28 disposed under the rim of the seat of the toilet bowl 12 which communicate with a lower chamber 30. Lower chamber 30 communicates in turn with the tank 10 through a flush valve assembly 32 and is vented by a conventional overflow tube 34. When the flush valve assembly 32 is opened during the flushing operation, water from the tank 10 drains through the open of flush valve assembly into the lower chamber 30 and through the toilet seat rim holes 28 into the bowl 12. In all other conditions, i.e., when the toilt is not being flushed, the holes 28 communicate via the lower chamber 30 and overflow the tube 34 directly into the tank 10. The device 16 according to the present invention is adapted to take advantage of this communication between the bowl 12 and tank 10 provided by the equipment already in place to remove foul odors therefrom. 
     The device 16 according to the embodiment shown in FIGS. 1-3, includes an exhaust fan 36 powered by an electric motor 38. The motor 38 is connected to a power source of 110 volts A/C which may be actuated either by a light switch or by a separate switch perhaps provided on the tank 10 or side walls 22. To support the fan 36 and motor 38, a fan support base 40 is provided to orient the motor 38 and fan 36 as to draw air through an opening 42 provided centrally in the barrier wall 18 as best shown in FIG. 3. When the fan motor 38 is energized, the fan 36 draws air from the tank 10 discharging it into the upper chamber 26. The relatively lower pressure in the tank 10 draws foul air from the toilet bowl 12 into the holes 28, lower chamber 30, up the overflow tube 34 and into the tank 10. The odorous air is then delivered by the fan into the upper chamber 26 to be purified and discharged from the device 16 as described hereinafter. 
     To maintain the above described air flow from the toilet bowl into the tank 10, the device 16 according to the present invention, as shown in FIGS. 1 and 2 includes an overflow tube adapter 44 which connects over the overflow tube 34 for the toilet flushing means. Adapter 44 includes a sleeve portion 46 which fits over the overflow tube 34 and further includes a portion defining a dip pipe 48 connected as a T to the sleeve portion 46. Dip pipe 48 has a C-shape terminating at a vent end 50 which, relative to the sleeve portion 46 is located medially. Coupled to the sleeve portion 46 is a suction tube 52 which acts to extend the overflow tube to vent to a location proximate the fan 36 as best shown in FIG. 1. Accordingly, the suction tube 52 is attached by a coupling 54 to the sleeve portion 46 and, opposite the coupling 44, includes an end 56 located through the opening 42 near the fan 36. As can be appreciated from FIG. 1, the suction tube 52 has a diameter smaller than the opening 42 to provide an open annulus 58 thereabout. To accomodate different styles of toilet flushing means, the suction tube 52 can have various configurations and lengths so as to locate its end 56 in the desired manner. A refill tube 60 is coupled between the suction tube 52 and water supply 62 for refilling of the tank 10. In a conventional manner, a float 64 controls the water supply 62. 
     In operation, the motor 38 is operated to cause the fan 36 to create a pressure differential between the tank 10 and the upper chamber 26 and toilet bowl 12. The foul air drawn from the toilet bowl up to the overflow tube 34 and through the adapter 44 is discharged into the upper chamber 26. The pressure differential between the upper chamber 26 at a higher pressure and the tank 10 at a lower pressure causes the foul air within the upper chamber 26 to be driven through at least one and preferably a pair of pourous filters 66 mounted and supported by the barrier wall 18. Apertures 68 are associated with the filters 66 to permit the air to pass through the barrier wall 18. Preferably, the filters 66 are of a charcoal type. The foul air discharged into the upper chamber 26 passes through the filters 66 which trap most if not all of the odorous vapors. In that the filters 66 are aranged closely to the water contained in the tank 10, the humidity provided thereby enhances the filtering action of the filters 66. The purified air after having passed through the filters 66 is discharged back into the tank 10. A portion of the filtered air passes from the device through an undercut 70 (FIG. 1) provided at one or both sides of the device 16. As shown, the undercut is made cooperatively at the lip 20 and side walls 22 for discharging of the purified air into the atmosphere. The remaining portion of the purified air within the tank is recirculated through the annulus 58 back to the fan 36. The continuous recirculation of purified air with the air supplied directly from the toilet bowl 12 is believed to enhance the filtering action of the device 16 in that a constant supply of air is provided to the fan 36. Further, the circulation of air is believed to enhance the life of the fan motor 38 since recirculation means that the fan will always have an adequate supply of suction air for cooling of the motor 38. 
     During the flushing operation, when the flush valve assembly 32 is open, a surge of water will block the overflow tube 34 as water is supplied to the toilet bowl. The water passing from the tank 10 through the lower chamber 30 blocks the supply of air from the toilet bowl 12. To provide a constant supply of air to the fan 36, as the water level in the tank 10 drops, the dip pipe 48 and more particularly its vent end 50 conveniently becomes exposed so that air within the tank 10 can be drawn therethorugh to the suction tube 52 and to the fan 36. Accordingly, even during flushing a constant supply of air is provided to the fan for recirculation thereof. When the tank is refilled with water and the level rises so as to submerge the vent end 50, suction air again becomes drawn through the holes 28 at the toilet bowl 12. 
     The foregoing operation of the device 16 continues until the device is turned off. 
     Turning to FIGS. 4 and 5, a further embodiment of the device is shown in detail. Similar parts will carry the same reference numeral. 
     The device 16 according to FIGS. 4 and 5, includes a modified base 40&#39; adapted to suspend the motor 38 and fan 36 over the opening 42. 
     To provide communication between the overflow tube 34 and the fan 36 and approved adapter 44&#39; is provided. The adapter 44&#39; is adjustable to accomodate different configurations and locations of overflow tubes and hence can easily be fitted to various styles of toilets. The adapter 44&#39; includes an S-tube 72 having one end 74 adapted to be closely fitted over the upper end of the overflow tube 34. The other end 76 of the S-tube 72 accommodates a first telescopic member 78. As best shown in FIG. 5, the one end 74 is coupled to the overflow tube via a coupling 75 which permits orientation of the S-tube 72 in a desired fashion. By providing the first telescopic member 78 should the configuration of the overflow tube 34 be such that the other end 76 positioned remote from the fan, the first telescopic member 78 may be positioned relative to the other end 78 so as to effectively extend S-tube 72 to a location proximate the fan 36. In this manner, the fan 36 can efficiently draw foul air from the toilet bowl as described above. 
     To provide a continuous supply of air to the fan 36, even during the flushing operation, the adapter 44&#39; further includes a dip leg 80 projecting downwardly from the S-tube 72 parallel to the overflow tube 34. The dip leg 80 accommodates a second telescopic member 82 having a vent end 50&#39;. For proper operation of the adapter 44&#39;, the second telescopic member 82 can be positioned relative to the dip leg 80 so as to contact and become submerged and sealed within the water contained in the tank 10 during most instances and when the toilet is flushed become open to provide a constant supply of air to the fan 36. 
     While I have shown and described certain embodiments of the present invention, it is to be understood that it is subject to many modifications without departing from the spirit and scope of the invention as set forth in the appended claims: