Abstract:
Disclosed is a ventilation device for removing offensive odors from within and near the toilet bowl, incorporating a modular asymmetrical exhaust airway to permit retrofitting onto a variety of toilet designs. The device may be used with a specially-designed toilet seat containing an internal duct and air outlets on its lower surface, or it may be used with a standard toilet seat by drawing gases from the bowl, through the space between the seat and the rim of the bowl, yet above the flood rim level specified in many plumbing codes. The invention also includes an easily disassemble design for sanitary cleaning.

Description:
RELATED APPLICATION DATA 
     This application is a continuation of U.S. application Ser. No. 09/070,103, filed Apr. 28, 1998, abandoned. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to the fields of plumbing and ventilation, and more particularly, to the ventilation of toilets and bathrooms. 
     BACKGROUND OF THE INVENTION 
     The need to remove unpleasant odors from the toilet areas has been with us since long before the invention of the flush toilet. To date, no one has developed a commercially successful method improving upon whole-room ventilation systems (i.e.. whole-room exhaust fans). Yet the need persists. Ventilation proximal to the source of odoriferous emissions would yield may benefits, including inter alia improved evacuation of odors and energy savings. This invention provides a device which overcomes the disadvantages of prior attempts to achieve toilet bowl ventilation, while improving on the currently predominant technology of exchanging large volumes of room air merely to eliminate a relatively small volume of methane. The device, unlike earlier attempts by others, meets all the present-day plumbing, fire and building codes in the United States of which the inventor is aware. 
     Modern building codes require exhaust systems in rooms housing toilets. Exhaustion of room air, typically from the ceiling, requires the exchange of large quantities of air, and does not necessarily protect occupants from unpleasant odors. This particularly true in public rest rooms and hotel bathrooms. Moreover, the exhaustion of a sufficient quantity of room air to create an acceptably odor-free environment created increased energy loads on buildings due to the influx of un-heated or un-air-conditioned air from the outdoors. Additionally, exhaustion at the source will eliminate the vast majority of methane and associated odors from the building&#39;s heating ventilation and air conditioning system. 
     While there has been a steady stream of inventive activity related to methods, of locally ventilating a toilet, none have yet met commercial success. This may be partly due to the difficulty in manufacturing and installing such devices, but also due to the fact that many, if not most, fail to meet applicable building codes. In addition, prior technology fails to effectively deal with the variety of existing toilet configurations and designs. The present invention incorporates a modular integrated design to permit retrofitting onto a wide variety of toilet conformations, while providing an aesthetically pleasing, and sanitary finishing installation. 
     Several patents have been awarded for inventions incorporating exhaust pathways into the toilet seat itself. For example, U.S. Pat. No. 3,916,459 granted to Ivancevic teaches a hollow hinge mechanism drawing contaminated air from the rear portion of the top surface of a toilet seat. Ivancevic also claims a switch mechanism to automatically switch on electronically-powered exhaust fan when the user is seated. In addition, Ivancevic teaches exhausting the gaseous waste into the plumbing system via specialized plumbing adapters. This design presents significant electrical and plumbing code compliance problems, as well as being highly complex to fabricate and install. Such a design would be difficult to retrofit into an existing laboratory. 
     U.S. Pat. No. 4,125,906 granted to Weiland also described a special toilet seat incorporating exhaust pathways. Weiland&#39;s toilet seat contains an inner conduit communicating to the interior of the bowl through a series of ports, and venting to an exhaust fan through a specialized hinge containing an articulating air passageway. Such a mechanism would be difficult to fabricate so as to fit existing toilet designs, and would create a sanitary problem in that no means is provided for cleaning the interior of the vented toilet seat. 
     U.S. Pat. No. 1,794,635 granted to Mills described a similar mechanism to Weiland, having an exhaust port incorporated into a hinge mechanism but also incorporating a mechanical cut-off to the air flow when the seat is raised. However, the Mills invention requires specialized manufacture of the porcelain china bowl to accommodate the mechanism. This is considered impractical for most applications. 
     U.S. Pat. No. 4,251,888 granted to Turner also incorporates ventilation ducts within the toilet seat, connected to an exhaust fan. However, the invention described by Turner places the electrical exhaust fan motor below the flood rim level of the fixture, violating building codes and creating a potential electrical hazard. Additionally, the Turner patent describes an electrical switch when built into the lower portion of the seat designed to turn the exhaust fan on automatically when the weight of a person is placed upon the seat. This adds an additional electrical hazard and code violation. The spring-loaded switch itself would also present a significant sanitary cleaning problem as it would accumulate filth and be difficult to sanitize. 
     U.S. Pat. No. 4,556,999 granted to Lindley incorporates internal exhaust airways, but adds a means to intake fresh, turbulent air. However, the Lindley invention teaches the use of a vacuum source rather than an exhaust fan, and utilizes a relatively small diameter exhaust passageway. As a result, the Lindley invention would be quite noisy if operated so as to remove a sufficient quantity of air ti effectively remove unpleasant odors and noxious methane. Additionally, it would consume significantly more electricity than a system using wider ducts and an exhaust fan. 
     Several patents have also been awarded which describe exhaust systems external to the seat itself. For example, U.S. Pat. No. 3,386,109 granted to Christian describes an elongated intake member attached to the underside of the seat, collecting air to be deodorized by a filter external to the toilet. However, the activated charcoal filter described in the Christian patent requires periodic replacement. Further, while it may remove unpleasant odors, it would not necessarily effectively remove noxious and flammable methane from the interior of the building. It further occupies significant space within the room housing the toilet, and may present an electrical hazard. 
     U.S. Pat. No. 4,175,293 granted to Stephens described a exhaust hood projecting into the toilet bowl, beneath the seat, and a seat-hinge mechanism incorporated into the sides of the hood. However, in the Stephen&#39;s invention, the intake is blow the flood rim, violating plumbing codes and presenting the hazard of causing over-flowing water to be drawn into the described system. 
     Similarly, U.S. Pat. No. 3,824,637 granted to Hunnicutt describes a collector unit essentially consisting of a generally flat airway protruding below the seat, intended to draw air into a separate activated charcoal unit. However, since the Hunnicutt invention draws from a single location at the rear of the bowl, like some of the other patents discussed, it will not effectively eliminate all odors from escaping from the front and sides of the bowl. 
     U.S. Pat. No. 4,701,966 granted to Schafer describes a plastic disposable duct located between the toilet seat and the rim of the bowl, with vacuum ports in a protruding lip on the inner portion of the ring. The ring is connected to a T-shaped vacuum base member with scored segments on the T-outlets to permit shortening. While the Ellis device is an attempt to solve the ineffective collection problems of such devices as Schafer and Hunicutt, it fails to meet plumbing code requirements because it draws air from below the flood rim level. Additionally, by raiding the seat, it introduces structural instability. 
     Other attempts at designing odor-eliminating systems have approached the problem by using the existing plumbing elements of a toilet in a manner to exhaust air. See, for example U.S. Pat. No. 3,192,539 granted to Marz and U.S. Pat. No. 4,165,544 granted to Barry. These approaches fail to meet plumbing code restrictions because they introduce what is considered sewer gas into potable water systems. Therefore, they may not be implemented in most locations in the United States because they pose the threat of contaminating the domestic potable water. 
     None of the foregoing attempts at solving the toilet ventilation problem has ever met with the commercial success because each wither requires specialized manufacture of conmmodes, or, if not retrofitted onto existing designs, is difficult to install, aesthetically displeasing and does not meet applicable plumbing, electrical and building codes. Moreover, prior art retrofit approaches will not fit an adequately broad range of existing toilet designs and configurations. Nor are any of the prior are designs conductive to sanitary cleaning. Only the &#39;966 patent described a disposable device aimed at sanitary concern. 
     One of the physical limitations related to retrofitting an exhaust system having an element such as an exhaust manifold located between the toilet seat and the toilet tank is the lack of physical space due to the presence of toilet seat mounting hardware, normally hinges. It would be desirable to provide an exhaust pathway which would physically fit directly behind a standard toilet seat without the need to specially manufacture a commode with additional clearance between the rear seat and the tank. 
     It is therefore an object of this invention to provide a system for directly ventilating a toilet bowl without the need to manufacture a specialized commode. 
     It is a further object of the present invention to provide a system for easily retrofitting a wide variety of existing toilet designs with a bowl-ventilation device. 
     It is a further object of the present invention to provide a system for retrofitting a toilet bowl ventilation device in an aesthetically-pleasing way. 
     It is a further object of the present invention to provide a toilet bowl ventilation device which will meet the majority of present-day plumbing, fire, electrical and other building codes. 
     It is a further object of the present invention to provide a toilet bowl ventilation device which can be effectively cleaned. 
     It is a further object of the present invention to provide a toilet bowl ventilation device which is both suitable for both retrofitting and new construction. 
     It is a further object of the present invention to provide a toilet bowl ventilation device which permits clearance for a toilet seat mounting hardware while providing a manifold between the ear of the toilet seat and the toilet tank. 
     SUMMARY OF THE INVENTION 
     This invention relates to a toilet bowl ventilation system which can be retrofit on a variety of toilet bowl configurations. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     This invention may be best understood by reference to the drawings, in which: 
     FIG. 1 is a perspective view of a toilet having a ventilation system embodying the present invention. 
     FIG. 2 is a perspective view of an exhaust plenum of the type described herein. 
     FIG. 3 is an enlarged elevational cross-sectional view of toilet incorporating an exhaust system embodying the present invention, specifically showing the toilet in an “up position.” 
     FIGS. 4 a  and  4   b  show two perspective views of a modular unit in association with a seat hinge. 
     FIG. 5 is a cross sectional view of the present invention showing the seat in the “down” position. 
     FIG. 6 is a perspective view of the hollow air plenum showing an alternative embodiment. 
     FIG. 7 is a cross sectional view of an alternative embodiment showing incorporation of an airway within the toilet communicating with the lower surface of the hollow air plenum. 
     FIG. 8 is a cross sectional view of an alternative embodiment showing the use of a solid (rather than hollow) toilet seat. 
     FIG. 9 is an exploded view of an alternative embodiment showing openable hollow toilet seat assembly. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIGS. 1 and 2 there is illustrated a toilet  10  comprising a toilet bowl  14  having an upwardly extending rim  18 , an upper rear horizontal plate  20 , a toilet seat  22  fastened to the bowl  14  by means of hinges  26  and an exhaust manifold  30  retained by the hinges  26 . The exhaust manifold is generally T-shaped. 
     In FIG. 2 it may be seen that the exhaust manifold  30  is fastened to the bowl by inserting mounting arms  32  under the hinge bolt shoulder  33  and then tightening the hinge mounting bolt-nut  34 . The exhaust manifold  30  comprises several-molder plastic pieces as follows: The hollow air plenum  38  is a combination of a base plate  42  and an upper cap piece  46  forming thereby a hollow space with an intake orifice  50 . The lower plate  42  of the hollow air plenum  38  is a minimum of ⅜″ thick to keep the lowest margin  47  of the intake orifice  50  above the “flood rim level” defined by many plumbing codes. The base plate  42  also incorporates the mounting arms  32  as integral extensions of the lower plate. The upper cap piece  46  defines the sides and top of the air intake or orifice  50  and contains an exit port  54  on each side. The outside vertical dimension of the hollow air plenum  38  at the front end (which is location of the intake orifice  50 ) is approximately ⅜″ excluding the thickness of the base plate  42 , and nominally 1⅝″ to 2″ at the back end  62  (see FIG.  3 )opposite the intake orifice  50 . The upper cap piece  46  may be separated from the base plate  42  and exhaust ducts  70 , 72  for ease of cleaning. The base plate  42  may be attached to the upper piece  46  by means of snaps  70   a  incorporated into the components parts. Alternatively, rotationally-engaging fasteners  70   b  may be employed. 
     Each of the two vertical sides  71  of the hollow air plenum  38  incorporates one port  54  adapted to accept an exhaust duct  70 , 72 . As illustrated in FIG. 2, one or more of the modular units  75 , 76  are connected to one another to form each of the ducts  70 , 72 , which when assembled, appear as illustrated in FIG.  1 . Also illustrated, one of the modular units  75 , 76  is connected to the cap piece  46  at the port  54 , thus connecting the duct  70 , 72  to the remainder of the manifold  30 . In this manner, each duct  70 , 72  is of modular design to permit it to be assembled in a multiplicity of lengths and thus fit a wide variety of toilet bowl designs. The modular units  75 ,  76  may be rotated in relation to one another to provide flexibility of installation. Specifically, a 90 degree elbow normally terminates at least one of the air ducts, and may be rotated to adjust the height above floor level the air ducts enter the wall  78  behind the toilet  10 . If desired, one of the exhaust air ducts may be omitted and the port  54  in the side of the hollow air plenum  38  plugged with a specially adapted terminating plug  82 . 
     FIG. 3 illustrates that the upper cap piece  46  provides clearance for the toilet seat  22  when in the position. The width of the hollow air plenum is approximately 3½ to 4″ to permit its location between the seat hinges  26 . 
     FIGS. 4 a  and  4   b  show two views of the asymmetrical exhaust duct modular units  75 , 76  which are specially adapted to permit clearance for the toilet seat hinge bolt shoulder  33 . 
     FIG. 5 illustrates that the present invention communicates with a hollow toilet seat  100 . When the seat is in the lowered position, the intake orifice  50  of the hollow air plenum  38  aligns with a matching orifice  104  in a hollow seat  100  to permit the contained movement of air from within the seat into a hollow air plenum  38 . Additional intake orifices  108  are incorporated into the lower surface of the seat so that air may be drawn from the interior of the bowl  14 , into the hollow seat  100 , through the intake orifice  50 , through the hollow air plenum  38 , through the exit ports  54 , through the exhaust ducts  70 , and, ultimately, to the outdoors. 
     FIGS. 6 and 7 illustrate a variation of the invention incorporates a third exhaust port  120  in the lower surface of the exhaust manifold  30 . The third exhaust port  120  mates to a specially provided exhaust orifice  122  in the upper surface of the toilet bowl, generally behind and between the toilet seat mounting hinges  26 . Reference to FIG. 7 illustrates that the special exhaust orifice  122  must normally be incorporated in the manufacture of the toilet bowl due to the great difficulty in retrofitting such a hole. Additionally, to meet plumbing codes, an upwardly extending lip  124  must be provided to keep the opening port  120  above the “flood rim level.” To provide flexibility on different installation configurations, the third exhaust port  120  may be created by removing a preformed punch-out plug  126  incorporated into the lower surface of the exhaust manifold  30 . In this embodiment, one or both sides of the port  54  may be plugged off to permit a broader range of installation options and improve aesthetic appeal. 
     FIG. 8 shows that, in an alternative embodiment, a standard solid toilet seat  112  may be used in place of a special hollow seat  100 . In such installation, the seat height above the bowl rim  18  is adjusted with shims or spacers  116  to a minimum of approximately ½″ to ⅝″, permitting the intake orifice  50  to draw air from between the bowl rim  18  and the lower surface of the toilet seat  112 . 
     FIG. 9 illustrates an alternative embodiment incorporating a hollow toilet seat  150  capable of being opened for ease of cleaning. The seat is formed by a lower portion  156  attached to an upper portion  160  by means or rotationally engaging fasteners  166 , snap fasteners  168 , or the like. 
     While this invention has been described by examples of the specific embodiments, it will be understood that it is not intended to limit the invention to the examples described. To the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. It is clear that this invention is susceptible to numerous modifications and embodiments within the ability of those skilled in the art and without the exercise of the inventive process. Accordingly, the invention should not be limited by the foregoing description, but should be defined only be the appended claims.