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BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates to deodorizer dispensers, chemical compounds for interfering with the formation of potassium phosphate, and more particularly, to an apparatus mountable within a urinal that both deodorizes and inhibits the formation of potassium phosphate urine calculus deposits in the urinal and in the drain pipes. 
         [0003]    2. Description of the Prior Art 
         [0004]    A urinal is a specialized toilet, or plumbing fixture, which receives only liquid body waste discharged almost always by a standing male, and conveys the waste through a trap seal into a gravity drainage system. A urinal is typically smaller and uses much less water than a full-function toilet, and can be installed at a convenient height to accommodate male users having a range of heights. Modern urinals generally are wall-mountable and feature an eliptical open bowl that is continuous with a rear wall of semi-eliptical cross section. Flush water is controllably dispensed through a plurality of flush apertures located in a ceiling of the urinal that is continuous with the rear wall. A drain, which is located at the bottom of the bowl, communicates with a trap that is, in turn, connected to the sewer system. 
         [0005]    Potassium phosphate is formed by the reaction of potassium, phosphoric acid and carbon dioxide. As urine typically contains all three compounds, urine calculus deposits, containing a combination of potassium phosphate and organic compounds eliminated by the body, are formed in urinals and in the drain pipes of urinals. As the organic compounds decay, the calculus deposits give off a characteristic foul odor that is present in poorly maintained men&#39;s rest rooms. Because urine calculus deposits do not readily dissolve in water, their removal is a challenge for janitorial staffs. After calcium, potassium and phosphorus is the third most abundant element found in the human body. Calcium, potassium and phosphorus are, respectively, the second and third most common elements found in the human body. The presence of potassium is essential for the regulation of the acid-base balance and water balance in the blood and the body tissues, for the synthesis of proteins from amino acids, for carbohydrate metabolism, for the building of muscle tissue, for normal body growth, and for the proper functioning of nerve cells, in the brain and throughout the body. With the proliferation of soft drinks, such as colas, which contain both phosphoric acid and carbon dioxide, these two ingredients are found in urine in increasing concentrations. 
         [0006]    In order to counteract the foul odor of decomposing urine, deodorant blocks are commonly placed inside urinals. For many years, deodorant blocks containing paradichlorobenzene and naphthalene were used to counteract odors in rest rooms. However, during the last several decades, it has been observed that exposure to that chemical is responsible for numerous health problems, including kidney and liver disease. Consequently, the use of paradichlorobenzene—particularly around children—has been prohibited in certain jurisdictions. Naphthalene has compiled a record of even greater toxicity than paradichlorobenzene. Other, less toxic aromatic compounds are now being used to combat foul odors in rest rooms. 
         [0007]    What is needed is an apparatus that is installable within the collector and flush receptacle a urinal that will not only release a refreshing aroma that counteracts urine odors, but also dispense a controlled amount of chemical compound that interferes with the formation of urine calculus deposits in the urinal and drain pipes of the urinal. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention provides a multi-function canister mountable within a urinal at the corner of the ceiling and rear wall thereof. The canister is held in place by a spring clip that is insertable in one of the flush apertures in the urinal ceiling. The spring clip biases the apparatus against the rear wall of the urinal, thereby maintaining it in place. As flush apertures near the center of some urinals are not sufficiently deep for insertion of the spring clip, due to their proximity to the central, fresh water inlet pipe, the spring clip is offset to one side of the apparatus so that the apparatus can be centered in the urinal for aesthetic reasons. For urinals having flush apertures that enter the top of the chamber on or about a 45-degree angle, a suction cup structure may be installed on the housing to assist with retention of the canister within the urinal chamber. 
         [0009]    The canister continually dispenses an odor counteracting aroma from an onboard fragrance tablet and, with each flush of the urinal, dispenses a controlled amount of a chemical compound that interferes with the formation of urine calculus deposits that installs within the urinal. The canister includes a housing having a reservoir containing the chemical compound in solid form. A deflector tray, which opens to the rear of the canister, is installed above the reservoir and is positioned near the base of the spring clip. Once the canister is installed within a urinal, with each flush, a stream of water exits the flush aperture in which the spring clip is installed and spills onto the deflector tray. A small opening in the deflector tray permits water to enter the reservoir. A layer of standing water in the reservoir slowly dissolves the supply of solid chemical compound and, with each flush, some of this dissolved compound in the standing water layer overflows from the reservoir into the deflector tray, and is expelled against the back wall of the urinal, whence it flows into the urinal bowl. For a currently utilized embodiment of the invention, the solid compound is sulfamic acid. In order to protect the sulfamic acid from moisture after the reservoir is filled and until it is installed, the sulfamic acid is covered with a layer of polyethylene glycol. After installation, the polyethylene glycol is quickly dissolved and the sulfamic acid exposed. The housing of the canister also includes a mounting location for the fragrance tablet. The canister may also include a grill which covers the reservoir and fragrance tablet and provides an attractive, finished appearance to the canister. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a front elevational view of the multi-function urinal canister; 
           [0011]      FIG. 2  is a rear elevational view of the multi-function urinal canister; 
           [0012]      FIG. 3  is an exploded, left-side elevational view of the housing showing the deflector tray positioned above and the fragrance tablet positioned to the right thereof; 
           [0013]      FIG. 4  is an exploded, left-side elevational view of the canister showing the housing assembled with the deflector tray and fragrance tablet, and the grill positioned to the right of the housing; 
           [0014]      FIG. 5  is a left-side elevational view of the fully-assembled canister; 
           [0015]      FIG. 6  is a top plan view of the deflector tray; 
           [0016]      FIG. 7  is a bottom plan view of the deflector tray; 
           [0017]      FIG. 8  is a rear elevational view of the deflector tray; 
           [0018]      FIG. 9  is a front elevational view of the deflector tray; 
           [0019]      FIG. 10  is a left-side elevational view of the deflector tray; 
           [0020]      FIG. 11  is a right-side elevational view of the deflector tray; 
           [0021]      FIG. 12  is a top plan view of the grill; 
           [0022]      FIG. 13  is a top plan view of the housing with the fragrance tablet installed thereon and the deflector tray removed; 
           [0023]      FIG. 14  is a top plan view of the housing with both the fragrance tablet and deflector tray installed thereon; 
           [0024]      FIG. 15  is a top plan view of the fully-assembled canister; 
           [0025]      FIG. 16  is a cross-sectional view of a urinal, taken through a flush aperture, and showing the spring clip of a canister installed therein; 
           [0026]      FIG. 17  is a front elevational view of a conventional, modern, auto-flush urinal in which a canister has been installed; 
           [0027]      FIG. 18  is an elevational view of a suction cup; 
           [0028]      FIG. 19  is a top plan view of a suction cup; 
           [0029]      FIG. 20  is a slide elevational view of the fully-assembled canister on which is installed the suction cup of  FIGS. 18 and 19 ; and 
           [0030]      FIG. 21  is a rear elevational view of the fully-assembled canister on which is installed the suction cup of  FIGS. 18 and 19 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0031]    The invention will now be described with reference to the included drawing figures. It is to be understood that the drawings are not necessarily drawn to scale, and that they are intended to be merely illustrative. 
         [0032]    Referring now to the front view of  FIG. 1 , the multi-purpose canister  100  has a fragrance tablet  101  with two elongated vertical apertures  102 A and  102 B that enable it to remain suspended on left and right hangers  103 A and  103 B, respectively. The fragrance tablet  101  is made of porous polymeric material that is impregnated with a volatile aromatic fragrance compound. A front cover  104  having a grill  105  formed from vertical ribs  106 A- 106 J snaps onto the canister housing, which is not visible in this view. A horizontal bar  107  that interconnects vertical ribs  106 D,  106 E,  106 F and  106 G provides a convenient space to mount a trademark. A spring clip  108 , which protrudes from the housing, is insertable in one of the flush apertures at the top of a urinal chamber. The spring clip  108  biases the canister  100  against the chamber rear wall, thereby maintaining it in place. As flush apertures near the center of some urinals are not sufficiently deep for insertion of the spring clip  108 , due to their proximity to the central, fresh water inlet pipe, the spring clip  108  is offset to one side (in this example, to the right) of the canister  100  so that the canister  100  can be centered in the urinal for aesthetic reasons. 
         [0033]    Referring now to the rear view of  FIG. 2 , the multi-purpose canister  100  includes a housing  201 . The outer edges of the snap-on front cover  104  are visible in this view. When installed in a urinal, that which is seen in this view faces the wall of the urinal chamber. The housing contains a reservoir filled with a water-soluble solid, a portion of which is dispensed with each flush to inhibit potassium phosphate scale formation on the interior surfaces, trap and drain of the urinal. The housing  201  has a central dispensing orifice  202 , from which the dissolved compound escapes from the reservoir. The orifice  202  communicates with a vertical channel  203  that directs the water into the urinal chamber. The spring clip  108  is attached to the housing  201 . 
         [0034]    Referring now to  FIG. 3 , this exploded view of the canister  100  shows the deflector tray  301  above the housing  201  and the fragrance tablet  101  to the right of the housing  201 . The left tablet hanger  103 A is visible in profile, as is a secondary left-side tablet support  302 A. A left upper front cover retainer projection  303 A is visible, as is a single center lower front cover retainer projection  304 . Aligning apertures (not shown in this view) in the front cover  104  snap over the projections  303 A,  303 B (not shown) and  304 , thereby retaining the front cover  104  in place on the housing  201 . 
         [0035]    Referring now to  FIG. 4 , this left-side view of the canister  100  shows the housing  201  assembled with the deflector tray  301  and fragrance tablet  101 , and the front cover  104  positioned to the right of the housing  201 . 
         [0036]    Referring now to  FIG. 5 , the canister  100  has been fully assembled. It will be noted that a portion of the housing  201  is exposed when the front cover  104  is installed thereon. It will also be noted that a lower panel  501  of the front cover  104  directs water that may flow over the fragrance tablet  101  to the rear of the canister. 
         [0037]    Referring now to  FIGS. 6 through 11 , the deflector tray  301  is shown from six different angles. It will be noted that the deflector tray  301  has a projecting tab  601  that fits into the central dispensing orifice  202  in the housing  201 , resting on the bottom edge thereof. It will also be noted that the deflector tray  301  has a bottom panel  602  that slopes to the rear of the canister, a front wall  603 , a left wall  604 , a right wall  605 , and a partial rear wall  606 . As a result of the sloping bottom panel  602  and partial rear wall  606 , water that flows into the deflector tray  301  is directed to the central dispensing orifice  202 . The deflector tray  301  also has a partial left rear flange  607  and a small right rear flange  608  that rest against the upper edges of the reservoir (not shown in this view) of the housing  201 , thereby supporting the deflector tray  301 . 
         [0038]    Referring now to  FIG. 12 , this top view of the front cover  104  shows the grill  105 , ten ribs  106 A- 106 J from which it is formed, and the horizontal bar  107  that interconnects vertical ribs  106 D,  106 E,  106 F and  106 G. It will be noted that a gap  1201  between a rear projection  1202  and a front projection  1203  provide a trap for the single center lower front cover retainer projection  304 . 
         [0039]    Referring now to  FIG. 13 , this top view of the housing  201  shows the reservoir  1301  that is filled with the water-soluble solid  1302 . It will be noted that the fragrance tablet  101  rests against three standoffs  1303 A,  1303 B and  1303 C, which are integral with the housing  201 . It will also be noted that the spring clip  108  is fixedly maintained between two vertical grooves formed by the rear wall  1305  of the housing  201  and first and second vertical strips  1306 A and  1306 B, which are integral with the housing  201 . For a currently utilized embodiment of the invention, the solid compound is sulfamic acid. In order to protect the sulfamic acid from moisture after the reservoir  1301  is filled and until it is installed, the sulfamic acid is covered with a layer of polyethylene glycol. After installation, the polyethylene glycol is quickly dissolved and the sulfamic acid exposed. 
         [0040]    Referring now to  FIG. 14 , it will be noted that the three standoffs identified in  FIG. 13  maintain the fragrance tablet  101  a distance from the front surface  1401  of the housing  201  for more effective fragrance dissipation. In this view, the deflector tray  301  has been installed above the reservoir  1301 . A portion of the water that escapes from the flush aperture in which the spring clip  108  is installed will enter the opening  1402  between the spring clip  108  and the right rear edge  1403  (looking from the front of the canister) of the bottom panel  602  of the deflector tray  301 . After several flushed, the water-soluble solid  1302  in the reservoir  1301  will be covered with water up to the level of the rear portion of the deflector tray  301 . Therefore water entering the opening  1402  will enter the reservoir  1301  and water containing a portion of the dissolved water-soluble solid  1302  will be expelled from the opening  1404  formed by the left rear edge  1405  of the bottom panel  602  and the rear wall  1305  of the housing  201 . The expelled water will then flow out the central dispensing orifice  202 , down the vertical channel  203  into the urinal chamber. 
         [0041]    Referring now to  FIG. 15 , the front cover  104  has been installed on the housing  201 . It will be noted that a rear portion of the deflector tray  301  is exposed. 
         [0042]    Referring now to  FIG. 16 , this cross-sectional view of a urinal  1601 , taken through a flush aperture  1602 , shows the spring clip  108  of a canister  100  installed therein. Flexing of the spring clip  108  biases the canister  100  against the rear wall  1603  of the urinal chamber  1604 . 
         [0043]    Referring now to  FIG. 17 , a multi-purpose canister  100  has been installed in this conventional, modern, auto-flush urinal  1701 . It will be noted that, as the canister  100  is centered in the urinal chamber  1702 , the clip  108  was necessarily inserted in a flush aperture  1602  that was offset from the center of the urinal chamber  1702 . As flush apertures near the center of some urinals are not sufficiently deep for full insertion of the spring clip  108 , due to their proximity to the central, fresh water inlet pipe  1703 , the spring clip  108  is offset to one side so that the canister  100  can be centered in the urinal chamber  1702  for aesthetic reasons. 
         [0044]    Unfortunately, there is a lack of standardization in the urinal manufacturing industry. Some urinals, for example, have flush apertures that enter the top of the chamber on a 45-degree angle. Such a design makes it difficult to bias the canister  100  against the rear wall of the urinal with the spring clip  108 . For this reason, a supplementary method must be used to secure the canister  100  within the urinal chamber. This supplementary method is shown and described with reference to drawing  FIGS. 18 to 21 . 
         [0045]    Referring now to  FIGS. 18 and 19 , an injection molded suction cup structure  1800  has a cup portion  1801 , a release tap  1802  continuous with the cup portion  1801 , and an attachment plug portion having a cap  1803  and a shank  1804 . Suction cups of this type are typically injection molded from transparent vinyl material. In  FIG. 21 , the suction cup structure  1800  is shown as having been molded from transparent material. 
         [0046]    Referring now to  FIGS. 20 and 21 , the suction cup structure  1800  of  FIGS. 18 and 19  has been installed within the central dispensing orifice  202  of the housing  201 . For installation within a urinal chamber having 45-degree-angled flush apertures, the spring clip  108  can be bent backwards to about a 90 degree angle, inserted within one of the flush apertures, and the suction cup structure can be used to assist retention of the canister  100  within the urinal chamber. 
         [0047]    Although only a single embodiment of the invention has been shown and described, it will be obvious to those having ordinary skill in the art that changes may be made thereto without departing from the scope and spirit of the invention as claimed.

Summary:
A multi-function canister, mountable within a urinal chamber, is held in place by a spring clip that is insertable in one of the flush apertures at the top of the chamber, and which biases the canister against the chamber rear wall. The canister includes an onboard fragrance tablet that continually dispenses an odor-counteracting aroma. The canister also includes a reservoir filled with a solid compound, a dissolved portion of which is released into the chamber with each flush by water flowing from the aperture in which the spring clip is installed. A deflector tray limits the amount of water flowing into the reservoir. The dissolved portion inhibits the formation of potassium phosphate scale (urine calculus) on the surfaces of the urinal chamber and drainage pipes. The solid compound may be sulfamic acid. The canister may also include a grill which covers and protects the fragrance tablet.