Abstract:
A portable toilet chemical additive charging system comprises a restroom cabana containing a toilet bowl which opens into a waste-holding tank. A water source, such as a separate water tank, is connected by a conduit to the toilet bowl for delivering flush water to the bowl when a flush pump, that is connected to the conduit, is actuated. The flush water passes through a control valve in the conduit. A chemical additive container is removably positioned near the toilet bowl and is connected by a tube to the control valve. The control valve injects a pre-determined amount of additive to the flush water when flush water is flowed through the control valve to the bowl. Preferably, the container is shaped to closely fit within a space between a vent pipe extending upwardly from the waste-holding tank and the adjacent interior surface of a wall of the cabana. A portion of the container is substantially transparent and exposed so that an observer may view the level of additive content in the container, while the remainder of the container is substantially concealed by the vent pipe.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     This invention relates to a system which provides a chemical additive to the flush water used in a portable restroom toilet. Portable restrooms, which are also referred to as portable chemical toilets or portable restroom toilets, in general, comprise a cabana or housing within which a toilet bowl and a waste storage tank is positioned. In some of these types of toilets, the toilet opening or bowl is formed in the upper surface of the waste-holding tank so that the bodily waste drops into and is stored within the waste-holding tank. The waste is removed from the tank from time to time as necessary. In some portable restroom toilets, rather than simply operating to drop bodily waste by gravity through the toilet opening into the waste-collecting tank, the waste may be deposited in a bowl, and a bowl flushing system is provided. In such a system the bodily waste is collected within the toilet bowl, which may have a trap or flap upon which waste is deposited. Then flush water is pumped into and through the bowl so that the waste is flushed past the trap into the waste-holding tank.  
         [0002]     Examples of portable restroom toilets, and constructions of their cabanas and toilets and waste tank components are disclosed in U.S. Pat. No. 3,447,167, issued Jun. 3, 1969 to David B. Harding, for a portable toilet cabana; U.S. Pat. No. 3,835,480, issued Sep. 17, 1974 to George W. Harding for a chemical toilet cabana; U.S. Pat. No. 4,031,572, issued Jun. 28, 1977 to George W. Harding for a chemical toilet cabana shell section; U.S. Pat. No. 4,577,351, issued Mar. 25, 1986 to George W. Harding for a portable toilet cabana; U.S. Pat. No. 4,831,671, issued May 23, 1989 to George W. Harding for a portable toilet cabana; U.S. Pat. No. 4,918,765, issued Apr. 24, 1990 to George W. Harding for a portable toilet cabana; U.S. Pat. No. 5,500,960, issued Mar. 26, 1996 to Richard L. Tagg for a flush system for outdoor portable toilets; and U.S. Pat. No. 5,560,050, issued Oct. 1, 1996 to Richard L. Tagg for a portable combined toilet and waste-holding tank.  
         [0003]     As shown by the examples, the portable restroom toilets were typically made of large sheets of plastic materials formed into walls, a base or floor, and a roof which were assembled together into the restroom cabana or housing. The waste-holding tank was formed to fit within the cabana and an opening formed in the upper surface of the tank served as a toilet opening into the waste-holding tank. In some prior constructions, a toilet bowl was provided below the opening. The bowl had an open lower end which opened into the waste-holding tank. In some of such restrooms, a urinal was also mounted within the cabana with a suitable pipe extended from the urinal into the waste-holding tank. In some, more luxurious types of portable restrooms, a sink, to which a tank of water was connected, provided hand-washing facilities within the cabana. Waste water from the sink flowed through a drain pipe into the waste-holding tank.  
         [0004]     These portable restrooms typically were carried from location to location on suitable trucks and positioned for use on a temporary basis. The waste-holding tanks were periodically emptied by means of a suitable tank truck having a pipe which could be inserted in the waste-holding tank for pumping the contents from the waste-holding tank into a tank on the truck for later disposal, such as into a municipal sewerage system.  
         [0005]     For sanitary reasons, as well as for aesthetic reasons, waste-flushing systems are desirable for flushing the bodily waste out of the toilet bowl area and into the waste-holding tank. Flushing systems have included either a separate water tank containing or storing flush water or a connection to a local running water supply system through a hose or pipe. In some such systems, “grey” water was used for flushing. This involved using some of the liquid contained in the waste tank as at least part of the flushing water. In those systems some liquid is drained from the waste tank and is re-circulated, which reduces the amount of fresh water required and the frequency of refilling a fresh water storage tank.  
         [0006]     An example of a flushing system is illustrated in U.S. Pat. No. 5,500,960, issued Mar. 26, 1996 to Richard L. Tagg for a “flush system for outdoor portable toilets.” This patent illustrates a system in which water contained in a storage tank that is positioned adjacent the exterior of the cabana can be pumped by a simple hand- or foot-operated pump into a conduit which carried water from the water storage tank into a bowl-shaped toilet receptacle that opens into the waste-holding tank. The water is sprayed into the upper area of the bowl by means of a perforated pipe arranged around the interior of the perimeter of the bowl.  
         [0007]     Other available flush systems have had a flap or closure at the lower end of the bowl-shaped toilet for temporarily supporting deposited bodily waste material. That material is dropped into the waste tank during the flushing of the toilet. The flap or “trap” may be arranged, for example, to either tip or swing downwardly under the weight of flush water to permit the waste to fall into the tank.  
         [0008]     In some portable restrooms, the waste-holding tanks are provided with a sump area where the fluids in the tank drain to a common location for facilitating pumping the contents out of the tank when the tank is emptied or to facilitate collecting grey water. Because of the nature of the restroom constructions and their uses, they typically exude obnoxious odors from their waste or sewage contents. To reduce the unpleasant atmosphere caused by odors, it is common to provide vent pipes which extend from the waste-holding tanks upwardly through the roofs or through one of the walls of the cabana. Nevertheless, obnoxious odors and the unaesthetic impression of insanitariness due to odors is a common problem in portable restrooms.  
         [0009]     In an attempt to reduce the problem of odors and to provide a more sanitary atmosphere, it is common for the personnel who service or maintain such restrooms to add an additive chemical to the toilet bowls and sumps and waste-holding tanks. Typically, these chemicals are blue in color which mask and inhibit any unsightly appearance of a bowl and, also, these chemicals neutralize the odors to a considerable extent. The additive may be referred to as a “charge.” 
         [0010]     As an example, the serviceperson may mix approximately five gallons of water with a pre-determined amount of a commercially available additive and pour this charge into the toilet bowl from which the charge flows into the waste-holding tank. Further as an example, the effect of such a charge might last, depending upon weather conditions and the type and amount of chemical additives, for as many as seven days. However, warm weather may require stronger chemical additives and more frequent “charges.” 
         [0011]     Because of intermittent maintenance of the restrooms and variations in the amount of time between applying charges, the effect of any particular charge varies and, also, too much or too little amounts of the additives may be applied. Since the amount or volume of a charge is discretionary with the serviceperson who manually applies the charge when servicing a restroom, a better control of the timing between charges and the amount of additives used are needed.  
         [0012]     The time required to mix and to add the “charges” and, also, the waste due to applying excessive amounts of the chemicals, contribute to increasing the operating costs. And insufficient amounts of additive or long periods between applications of successive additive charges suggest poor service quality or lack of maintenance as manifested by strong sewage odors.  
         [0013]     Thus, there is a need for a simple, inexpensive, system for providing an adequate “charge” or amount of chemical additive on a consistent, periodic, basis, without depending upon the manual service calls and the manual applications, particularly with toilets which have a water-flush system. In the case of a water-flush system, which may use fresh water or gray water, there is also a need to reduce unsanitary appearances and odor problems, which frequently arise by the failure of a toilet user to flush the toilet after use.  
         [0014]     Hence, the invention herein is concerned with providing an additive charge system which operates during the normal flushing of the toilet so as to minimize or alleviate the foregoing problems.  
       SUMMARY OF THE INVENTION  
       [0015]     The invention herein contemplates a simplified chemical additive charging system which is installed in a portable restroom toilet for injecting small, pre-determined, amounts of chemicals into the water which flushes the toilet. In general, the system is applicable to portable restroom toilet systems involving a cabana or housing containing a waste-holding tank having an upper surface opening formed as a toilet seat or bowl. Thus, bodily waste is deposited into the waste-holding tank through the opening. A fresh water or gray water flush system conveys water into the bowl area for flushing waste material into the tank. A trap or flap within the bowl area may temporarily hold deposited waste until the water flush operates. Alternatively, a direct gravity drop system may be used. In either event, a flush pump is activated to flush urine and feces into the waste-holding tank. Simultaneously, the chemical charging system injects some chemical additive into the flush water. Conventional chemical additives that are used, typically are blue in color so that the additives mask the flushed materials for aesthetic purposes and, simultaneously, inhibit or neutralize odors emanating from the waste sewerage.  
         [0016]     It is contemplated to operate the system by providing a source of water which may be a separate water storage tank or a hook-up to a nearby running water supply system. The water tank may be positioned either within the housing or at the exterior of the housing and connected through a conduit to the toilet bowl area. The water may be pressure-flowed into the bowl area by means of a suitable pump. The pump may be manually operated so that the toilet may be manually flushed by the toilet user at appropriate times. Meanwhile, the additive, which is provided in a separate container, is drawn into the water-flushing system, through a control valve, which controls or passes a pre-determined amount of the additive into the water flow or into the toilet bowl during the flushing actuation.  
         [0017]     It is further contemplated to provide the chemical additive in an enlarged bottle-like container which may be loosely placed upon the upper surface of the waste-holding tank near the toilet opening. In typical toilet systems, a vent pipe extends upwardly from the waste tank and then extends outwardly of the housing either through a sidewall or through the roof of the housing. Hence, the container may be shaped to fit in the space between the vent pipe and the wall of the housing. Preferably, it is shaped to fit within a space at the corner area that is formed between the juncture of the rear wall and a side wall and the vent pipe of the housing. With that construction, the bottle-like container may be filled, as necessary, by maintenance personnel who periodically service the portable toilets. Otherwise, the container may be shaped to fit behind the vent pipe and the wall adjacent the vent pipe. Preferably, the container is shaped to fit closely within the corner space at the rear of the vent pipe so that it is not conspicuous. The container has a front wall which is formed with a vertical channel or depression that partially receives or envelops the adjacent portion of the vent pipe. Thus, the container is inconspicuous, that is, it is sufficiently concealed by the pipe so as to be visually less noticeable to users of the restroom.  
         [0018]     In order to facilitate servicing the charge system, the container may be formed with a transparent portion or a portion which is at least sufficiently transparent to permit a serviceperson to view the level of the contents in the container. That portion would be arranged along the side of the vent pipe, substantially clear of obstruction by the pipe, so as to be visible to a serviceperson who is standing within the housing and looking rearwardly towards the pipe at the back wall. Thus, the amount of fluid within the container can be readily observed and the container may be either removed and replaced with a fresh filled container or, alternatively, the container may be refilled by the serviceperson at that time.  
         [0019]     Consequently, an objective of this invention is to provide a system wherein chemical additives are positioned within a typical portable restroom toilet, in a manner that the container holding the additive is substantially inconspicuous and yet its contents may be easily observed by a serviceperson who can quickly and efficiently remove and replace, or can refill, a container when necessary.  
         [0020]     Another object of this invention is to provide a chemical charging system which will automatically inject relatively small, pre-measured amounts, of chemical additives into the flush water when the flush water is pumped through the toilet bowl area for flushing purposes. Similarly, this system would operate to provide additives within a sump area of the waste-holding tank at the time flush water is passed into the tank by the actuation of the flush pump.  
         [0021]     Yet another object of this invention is to provide a simplified system for enhancing the flush system in a portable chemical toilet by substantially reducing obnoxious odors and masking unaesthetic appearing materials in the toilet.  
         [0022]     It is a further object of this invention to provide a relatively inexpensive, simplified system which requires minimal labor for installation and servicing, for automatically injecting into the flush water system chemical additives each time that the flush system is operated for flushing waste material into the waste-holding tank.  
         [0023]     These and other objects and advantages of this invention will become apparent upon reading the following description, of which the attached drawings form a part.  
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0024]      FIG. 1  is a schematic, perspective view of a portable restroom with an additive container.  
         [0025]      FIG. 2  is a fragmentary, perspective view showing an additive container placed behind a vent pipe in the corner area formed by the intersection of the rear and a side wall.  
         [0026]      FIG. 3  is a schematic, cross-sectional, plan view taken in the direction of arrows  3 - 3  of  FIG. 1 .  
         [0027]      FIG. 4  is a fragmentary, schematic, cross-sectional view of the toilet and lower portion of the cabana.  
         [0028]      FIG. 5  is a perspective view of a chemical additive container.  
         [0029]      FIG. 6  is a top, plain view showing the container positioned against a vent pipe.  
         [0030]      FIG. 7  is a schematic diagram showing the flushing system and including the water flush and additive charging system.  
         [0031]      FIG. 8  is a schematic diagram showing the flushing system with a top plan view of the toilet bowl and bowl flush conduit.  
     
    
     DETAILED DESCRIPTION  
       [0032]     Referring to the drawings,  FIG. 1  illustrates schematically, in perspective, a conventional portable restroom  10 . The restroom comprises a cabana or housing  11  formed with sidewalls  12 , a rear wall  13  and a front wall  14 . The front wall is provided with an entry opening which is closed by a door  15  connected by hinges (not shown) along one of the jambs of the opening. The door is provided with conventional door handles or knobs  16  which may include a latching device for fastening the door in close position when the restroom is in use.  
         [0033]     The door is provided with screened openings  17 . Similarly, the sidewalls are provided with screened openings  18 .  
         [0034]     The floor of the cabana is formed by a floor panel  19  which is supported upon structural beams  20  (see  FIG. 2 ). Further, a roof  21  is positioned over the upper edges of the walls. The walls  12 ,  13  and  14 , and the floor panel  19  and the roof  21  are secured together in conventional manners to form the substantially rigid, small cabana or housing  11 . A typical vent pipe  22  extends upwardly through the roof  21 , to assist in removing odors from the unit, as will be described below. The vent pipe may, alternatively, be extended, somewhere along its length, horizontally through one of the adjacent side or rear walls and then upwards and outwardly for venting purposes.  
         [0035]     The cabana is mounted upon skids  23 , which enable supporting the cabana upon ground and sliding it short distances as may be necessary for properly locating the cabana in a usable position.  
         [0036]     A waste-holding tank  25  is arranged within the cabana for the receipt and storage of bodily waste materials. A toilet opening  26  is formed on the upper surface of the tank. As illustrated in the drawings at  FIGS. 1-3 , a portion of the upper surface of the holding tank may be depressed or recessed to form a recessed part  27  within which the toilet opening  26  is formed. A suitable toilet seat  28  may be mounted above and around the opening in the tank surface. The seat may be hinged for lifting it upwardly out of the way or may be statically mounted on the tank.  
         [0037]     In many conventional portable restroom toilets, a toilet bowl  29  (see  FIG. 4 ) may be positioned below the opening in the tank surface and extended beneath that opening. In turn, the bowl has a lower opening  30  into the waste-holding tank. In some such toilet units, a hinged trap or flap  31  is arranged to normally close the lower opening in the bowl. The trap or flap may be weight-operated so that upon deposit of waste material upon the trap, along with flush water, the flap or trap will swing downwardly to open the bowl into the tank. Conventional mechanisms may be used for the purpose of holding the flap or trap in a closing position and for permitting it to swing downwardly upon use and to return to its upper closing position.  
         [0038]     In portable restroom toilet constructions where water is provided for flushing purposes, a water tank  33  may be positioned, for example, at the outside of the rear wall of the cabana. The water tank normally has a water tank refill nozzle or opening  34 , which may be closed with a suitable cover or cap, so that the tank may be refilled with water periodically, as needed, during the normal maintenance or servicing of the unit. Alternatively, where available, a separate water source (not shown) may be hooked up by a hose to the cabana for providing flush water. Since these types of portable toilets are frequently used in areas where a continuous running water supply is not nearby, a separate water tank is necessary.  
         [0039]     A flush system which provides flush water, on demand, to flush the toilet bowl, is schematically illustrated in  FIGS. 7 and 8 . The system includes a water line  35  from the water tank or water source to the toilet bowl. The water line includes one or more check valves  36  which prevent the water from backing from the bowl into the water tank. These are conventional valves, that are commercially available. The water line also includes a mix valve  37  and a check valve  38  within or adjacent the mix valve, again to prevent water from flowing backwards to the mix valve and then into the water tank.  
         [0040]     A section  39  of the water line extends to a water distribution pipe  40  which is installed within the bowl along the upper portions of the bowl. The pipe, for example, may be U-shaped and perforated so as to distribute streams of water into the bowl for flushing purposes when the flushing system is operated. Other types of distribution devices may be used for distributing water within the bowl for flushing. Various commercially available or conventional devices are used for this purpose and the particular device utilized is not pertinent to the invention herein.  
         [0041]     In order to flush the toilet, a conventional pump  42  is provided. The pump may be a foot-operated device located on the floor of the cabana adjacent the front of the waste-holding tank. Alternatively, a hand-operated pump which may be provided, for example, upon the upper surface of the waste-holding tank for manual operation of the pump. The pump may be manually operated or, alternatively, an electrically-operated pump may be used where electrical connections are available. A line  43  from the pump connects the pump to the mix valve or the water line  35  which extends from the water-holding tank  33  to the water-flushing distribution device  40 .  
         [0042]     The flushing system described above is known and is available in various versions. The invention herein contemplates adding to the known flushing system within a conventional portable restroom toilet arrangement, a chemical charging system for injecting chemical additives into the flushes when the flush system is operated. The chemical charging system includes a container  45  or bottle within which the chemical additive material is stored and is removed in increments as each flush is activated.  
         [0043]     The container  45 , preferably includes a front wall which is provided with a groove or indentation  46  of the size and shape to receive an adjacent portion of the vent pipe  22  (see  FIG. 6 ). The container also includes angled rear walls  47  which may fit adjacent to or in contact with the corner  47  formed by the connected edges of the rear and a sidewall of the cabana. Thus, it is contemplated to position the container within the space between the vent pipe and the adjacent portions of the side and rear walls, that is, in the corner space rearwardly of the vent pipe. Thus, the container is relatively inconspicuous within the cabana.  
         [0044]     Preferably, the container may be removed, when empty, and replaced with a filled container during routine servicing or maintenance of the restroom. Alternatively, it may remain in place and be refilled with chemical additive materials as needed.  
         [0045]     To facilitate the refilling or the determination as to when the container requires more material, the front wall  48  of the container includes a vertical, panel-like, portion  49  adjacent the groove  46 . That portion of the container may be transparent or translucent to provide a window through which the contents of the container may be visibly determined by an observer. The entire container may be formed of a translucent or relatively transparent material or only that one portion of the container may be formed as the viewing window. Index markings  50  on the portion  49  may be provided to visibly indicate the quantity of liquid additive remaining in the container.  
         [0046]     The container is provided with a refill spout  52  which is covered by a cap  53 . For security, a lock (not shown) may be mounted on the cap to keep the cap from being removed by an unauthorized person. The particular lock may vary, where a lock is used.  
         [0047]     The container also is provided with a discharge spout  54  which may be in the form of a conventional tube coupling and a short tubular extension positioned in either a side or front or rear wall section of the container. Alternatively, a threaded opening instead of a coupling, may be formed in the wall of the container for that purpose. A conduit or discharge line  55  is connected to the tube coupling spout or discharge tube or connected to the threaded opening to deliver additive from the container to a metering or measuring dispenser  56  and then through a check valve  57  to the mix valve  37 . The volume of the additive is controlled by the metering or measuring dispenser. The chemical additive is mixed with the flush water and carried into the toilet bowl along with the flush water.  
         [0048]     Mixing and metering control devices which control the amount of fluid passing through the dispenser when actuated, are commercially available. Various available devices can be utilized for this purpose, depending upon the cost and the durability of the device. Thus, the particular metering dispenser which is utilized here can be varied and can be selected by those skilled in the art to fulfill the purpose of passing a measured, pre-determined, amount of additive liquid from the container into the flush water line when the flush water line is actuated by operating the pump.  
         [0049]     As mentioned above, the container is fitted within the corner space  59  behind the vent pipe which is conventionally used to remove odors from the waste storage tank. The pipe obscures the container. Hence, because the container is inconspicuous, most users of the restroom will not observe or pay attention to the container, leaving it undisturbed. The container, during a service call by a serviceperson, can be visually observed from a position located within the housing in front of the waste tank. Particularly, the markings  50  on the exposed front edge portion of the container can be viewed to determine the level of additive within the container. That would easily indicate to the maintenance person when the additive level in the container should be restored by adding more additive to the container or that the container should be removed and replaced with a filled container.  
         [0050]     When the toilet bowl is flushed by activating the pump, urine and feces collected within the toilet bowl upon the bowl trap will slide off and dump into the waste-holding tank. By way of example, the trap may be calibrated to close under the flushing action and, in addition, may be calibrated to retain a small amount, as for example, four fluid ounces of chemical additive either with or without some flush water so that the toilet bowl contains a small amount of liquid between flushes, That will provide a more pleasant fragrance and a more aesthetic appearance to the users of the restroom.  
         [0051]     The line from the additive container may be arranged to supply the chemical additive, through the connection conduit, to the flush device within the toilet bowl, separately from the flush water tank that is entering the bowl when the flush is operated. That is, by a direct connection, additive may be placed within the bowl by the distribution device during or immediately after the flushing has occurred, in which case, a pre-determined, small amount of additive will enter the toilet bowl, after the flap or trap is closed following flushing, and the additive will remain within the bowl. That limited amount of additive will provide a liquid covering of the trap within the bowl. Because of a blue or other coloring, the chemical odor will mask sewerage odors from the tank as well as any unsightly appearances of the bowl to the user.  
         [0052]     The particular chemical additive used may be selected by those skilled in the art from available toilet chemicals. By way of example, a fluid ounce of a commercial additive chemical may be mixed with a much larger amount of water, such as an ounce of chemical to 64 fluid ounces of water, in the container. That volume may be sufficient, for example, to treat 30 gallons of sewerage generated from 20 gallons of water from the fresh water reservoir that is used to flush the bowl. Hence, a limited, relatively small and exact amount, of chemical additives may be consistently used. That helps to control the costs of operating the restroom. By using a limited amount of additives, the bowl can have a fresh smell or odor each time the bowl is flushed and the effects of the additive will last a longer time because of the regular small amounts of additive injected into the system. That is, the effects of the chemicals will not dissipate or dilute in the waste tank during interims between servicing the portable restroom.  
         [0053]     Different types of additive injector valves or measuring or metering valves are commercially available. Thus, the selection of the valves depends upon obtaining a commercially available valve of a size to fit within the unit, which will reliably dispense pre-determined quantities of additive needed on a regular basis, and a valve that is economical and easily installable by conventional plumbing methods. Thus, the particular metering or dispensing valve selected is not significant, other than that it be properly selected from those that are available on the market.  
         [0054]     Having fully described an operative embodiment of this invention, it is desired that the foregoing description be read as merely illustrative of preferred embodiments of this invention and not in a limiting sense. Thus, the invention may be further developed within the scope of the following claims.