Abstract:
A submersible apparatus, having at least one aperture formed in the body of the apparatus and one or more sanitizing or disinfecting tablets being contained within the apparatus, is placed into a swimming pool or other body of water. Initially, the combined mass of the apparatus and the chlorine tablets contained within the body of the apparatus will have slightly negative buoyancy and, as the apparatus sinks into the water, the position of the apparatus will stabilize (e.g., reach neutral buoyancy) at a position at or near the bottom of the swimming pool. As the chlorine tablets interact with the water in the swimming pool and slowly dissolve, the buoyancy of the apparatus increases (becomes more positive) and the apparatus gradually rises vertically until it reaches the surface of the swimming pool.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This non-provisional patent application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/267,428, under 35 U.S.C. §120, which application was filed on 7 Dec. 2009, which application is now pending and which application is incorporated by reference herein. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Technical Field 
         [0003]    The present invention relates generally to swimming pools and more specifically relates to disinfecting water contained in swimming pools. 
         [0004]    2. Background Art 
         [0005]    Chemicals used for swimming pool water disinfection must meet certain conditions in order to be useful. They should be relatively harmless and non-irritating to swimmers and attendants. They must be active in small concentrations and remain their activity for a relatively long period of time. Contrary to drinking water disinfectants, disinfectants used for swimming pool treatment must be active in the pool itself, because pollutions and pathogenic microorganisms are constantly added to the water. Therefore, it is necessary for the water to maintain a residual disinfectant concentration. The disinfectant should also be easily traced and measured and should be safe to store and use under normal operating circumstances. 
         [0006]    Chlorine-based disinfectants are among the most frequently applied disinfectants and oxidizers for swimming pool treatment. Generally, chlorine [hypochlorous acid (HOCl) or hypochlorite (OCl − )] in the form of liquid or tablets is introduced into a swimming pool or other body of water in order to minimize the growth of undesirable algae, bacteria, mold, etc. 
         [0007]    It is desirable to keep the concentration of chlorine in the swimming pool at a relatively stable level because either too much chlorine or too little chlorine can cause problems. The level of chlorine needs to remain relatively high because if the concentration of chlorine in the swimming is too low, the water will be unsafe for swimmers. However, if the concentration of chlorine is too high, the excess chlorine can cause eye and mucous membrane irritation, as a result of chloramine formation. 
         [0008]    Although standards for chlorine concentration in swimming pools vary, one typical threshold for available chlorine sets a minimum concentration for swimming pools at 0.5 mg/l. A typical maximum threshold level is set to 1.5 mg/l. When using cyanic acid as a stabilizer, atypical minimum and maximum threshold values might be set respectively at 2.0 mg/1 and 5.0 mg/L. For outdoor swimming pools and indoor pools smaller than 20 m 2 , the maximum chlorine concentration level may be set to 5.0 mg/l. 
         [0009]    While there are a number of devices and methods used for stabilizing the chlorine concentration in swimming pools, most fall short in one or more ways. For example, it is not uncommon to introduce liquid chlorine directly into the water. However, liquid chlorine can be very corrosive and caustic. Containers of liquid chlorine can also release chlorine gas when opened, so it is important to avoid breathing the fumes. Finally, liquid chlorine may be difficult to store over long periods of time. 
         [0010]    Another popular chlorination method involves the use of chlorine in the form of small tablets. This method uses a “floater” device to contain the tablets for use in the swimming pool. Often manufactured in the shape of a duck or small cylindrical device, this buoyant product is designed to hold one or more chlorine tablets and float on the surface when it is placed into a body of water (e.g., swimming pool). A number of apertures or openings are typically formed in the body of the floater device and water from the swimming pool is allowed to flow though the openings, contacting the chlorine tablets and, as the chlorine tablets dissolve, chlorine is introduced into the water contained in the body of water. 
         [0011]    While this device successfully adds chlorine to the water, there are a number of problems. Since the device floats on the surface of the water, the chlorine is added to the surface of the water where, depending on the ambient conditions, it may rapidly dissipate into the surrounding atmosphere. Additionally, the device is designed to float on the surface, making it an attractive target for young children who may view the device as a “toy” to be played with. Prolonged contact with the chlorine tablets may cause harm to any child who handles the device. Further, it is relatively difficult, if not impossible, to determine when or if the chlorine tablets contained inside the floating device have completely dissolved. This means that the floating device may be empty for some period of time and no chlorine will be added to the swimming pool until someone remembers to check the device to determine that the tablets have dissolved. So, while relatively simple to use, the floating chlorination device is far from perfect. 
         [0012]    Accordingly, without additional improvements in the equipment and methods used in swimming pool chlorination, the ability of swimming pool owners and operators to stabilize chlorine levels at desirable levels will remain suboptimal. 
       BRIEF SUMMARY OF THE INVENTION 
       [0013]    An apparatus for enhanced chlorination of bodies of water (e.g., swimming pools) is disclosed. The apparatus has a variable total mass (and buoyancy) based on the combination of the mass of at least one chlorine tablet placed into the body of the apparatus and the inherent mass of the apparatus itself. When the apparatus, with the chlorine tablet(s) inside, is placed into the swimming pool, the apparatus sinks towards the bottom of the swimming pool. As the chlorine tablet(s) dissolve, chlorine is released into the water contained into the swimming pool and the apparatus begins to rise towards the surface of the pool. Once all or substantially all of the chlorine tablet(s) have dissolved, the apparatus reaches the surface of the pool where it signals the need to place more chlorine tablet(s) into the apparatus. Once the apparatus has been refilled with chlorine tablets, it can be simply placed back into the swimming pool. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0014]    The preferred embodiments of the present invention will hereinafter be described in conjunction with the appended drawings, wherein like designations denote like elements, and: 
           [0015]      FIG. 1  shows an apparatus for chlorinating swimming pools in accordance with a preferred exemplary embodiment of the present invention; 
           [0016]      FIG. 2  shows an apparatus for chlorinating swimming pools in accordance with a preferred exemplary embodiment of the present invention; 
           [0017]      FIG. 3  shows an apparatus for chlorinating swimming pools in accordance with a preferred exemplary embodiment of the present invention; 
           [0018]      FIG. 4  shows an apparatus for chlorinating swimming pools in accordance with a preferred exemplary embodiment of the present invention; 
           [0019]      FIG. 5  shows an apparatus for chlorinating swimming pools in accordance with a preferred exemplary embodiment of the present invention; 
           [0020]      FIG. 6  shows a cap portion of an apparatus for chlorinating swimming pools in accordance with a preferred exemplary embodiment of the present invention; and 
           [0021]      FIG. 7  shows a method for chlorinating swimming pools in accordance with a preferred exemplary embodiment of the present invention; 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    In general, according to the fifth proposition of Archimedes, any object, wholly or partially immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object. In the real world, this principle is observed by noticing that an object tends to become more buoyant in water as it loses mass, due to the relationship between mass and weight. 
         [0023]    In accordance with the most preferred embodiments of the present invention, an apparatus is configured to accept one or more chlorine tablets into the body of the apparatus. When the apparatus, with the chlorine tablets inside, is placed into the swimming pool, the apparatus sinks towards the bottom of the swimming pool. The combined weight/mass of the chlorine tablet and the apparatus changes over time as the chlorine tablets inside the apparatus dissolve. As the chlorine tablets dissolve, chlorine is released into the water contained into the swimming pool and the apparatus begins to rise towards the surface of the pool. Once all or substantially all of the chlorine tablet(s) have dissolved, the apparatus reaches the surface of the pool where it signals the need to place more chlorine tablet(s) into the apparatus. 
         [0024]    Referring now to  FIG. 1 , an apparatus  100  for chlorinating swimming pools in accordance with a first preferred exemplary embodiment of the present invention is depicted. As shown in  FIG. 1 , apparatus  100  comprises a pair of caps  110  fitted onto a substantially cylindrical hollow body  120 . Apparatus  100  is substantially capsule-shaped, with the overall appearance of an elongated spheroid. Body  120  comprises a plurality of apertures  130 . The interior space of apparatus  100  can be accessed by removing one or more of caps  100 . Caps  120  may be attached to body  120  by compression fit. Alternatively, in at least one preferred embodiment of the present invention, body  120  and caps  110  may be manufactured with cooperating screw threads so that caps  110  may be screwed onto body  110 , similar to the process used in screwing nuts onto threaded bolts. The mass of apparatus  100  is calculated so that apparatus  100  will be buoyant and float on the surface of the water contained in a swimming pool when the interior space of apparatus  100  is empty. 
         [0025]    When apparatus  100  is to be deployed for chlorinating the water in the swimming pool, one or more of caps  110  may be removed and the interior space of body  120  is provided with one or more chlorine tablets (not shown this FIG.). The inner diameter of body  120  is manufactured to be compatible with the outer diameter of standard chlorine tablets, allowing the chlorine tablets to be positioned within the interior space of apparatus  100 . The addition of the chlorine tablets to the interior space of body  120  will increase the effective mass of apparatus  100 , thereby creating a less buoyant apparatus  100 . 
         [0026]    When placed into a body of water, apparatus  100  will gradually sink towards the bottom of the swimming pool by virtue of the combined mass of apparatus  100  and the chlorine tablets that have been positioned inside apparatus  100 . Further, once apparatus  100  has been placed into the water, water will enter body  120  via apertures  130 , allowing the water to contact the surface of the chlorine tablets. The chlorine tablets will gradually dissolve and release chlorine into the water via apertures  130 , thereby chlorinating and disinfecting the water. As the chlorine tablets dissolve, the combined mass of apparatus  100  and the chlorine tablets will be reduced and less water will be displaced by apparatus  100 . The result will be that apparatus  100  will gradually rise to the surface of the water, chlorinating the water as it rises. By controlling the number of apertures  130  formed in body  120  and by controlling the number of chlorine tablets placed into body  120 , the appropriate amount of chlorine for various amounts of water can be provided by apparatus  100 . In the most preferred embodiments of the present invention, apparatus  100  will be configured with some type of buoyant material in one cap  100 , thereby urging apparatus  100  to maintain a substantially vertical position in the water along a vertical axis  150 . 
         [0027]    Referring now to  FIG. 2 , an alternative preferred embodiment of an apparatus for chlorinating swimming pools is depicted. As shown in  FIG. 2 , apparatus  200  is similar to apparatus  100  of  FIG. 1  except that apparatus  200  has been fitted with a pair of skids  210 . Skids  210  are affixed to body  120  by struts  220 . Skids  210  may be substantially cylindrical and be fitted with ballast. This configuration will provide a horizontal orientation for apparatus  200  in the water. Skids  210  are configured to prevent body  120  from contacting the bottom surface of the swimming pool. As shown in  FIG. 2 , longitudinal axis  250  will be substantially parallel with the surface of the body of water into which apparatus  200  has been placed. In this configuration, body  120  may be configured as a two-part body  120 . The two pieces of body  120  may be defined as an upper body section and a lower body section where the upper body section and lower body section are each a half-cylinder, joined together at longitudinal axis  250 . Cap portions  110  will be sized so that the inner diameter of cap portions  110  will be just larger than the diameter of the upper body section and a lower body section. This will allow cap portions  110  to fit over the upper body section and a lower body section of body  120  and thereby hold upper body section and a lower body section together. 
         [0028]    Referring now to  FIG. 3 , a schematic diagram of a swimming pool  300  being chlorinated by apparatus  100  of  FIG. 1  is depicted. Apparatus  100  is placed into swimming pool  300  at position 1 and, due to the combined mass of apparatus  100  and the chlorine tablets placed inside apparatus  100 , apparatus  100  will gradually sink to position 2. The combined mass of apparatus  100  and the chlorine tablets placed within apparatus  100  will be calculated so as to ensure that apparatus  100  will be suspended slightly above the floor of swimming pool  300  at position 2, thereby preventing apparatus  100  from contacting the bottom surface of swimming pool  300 . As previously explained, the chlorine tablets inside apparatus  100  will gradually dissolve and, due to the reduced mass, apparatus  100  will gradually rise towards the surface of swimming pool  300  until it reaches position 3. Once apparatus  100  reaches position 3, the operator of swimming pool  300  will be visually notified that apparatus  100  has returned to the surface and apparatus can be filled with additional chlorine tablets and re-deployed. 
         [0029]    Referring now to  FIG. 4 , a schematic diagram of a swimming pool  400  being chlorinated by an alternative preferred embodiment of apparatus  100  of  FIG. 1  is depicted. As shown in  FIG. 4 , apparatus  100  of  FIG. 1  has been connected to a floatation device  410  by a flexible cord  420 . Floatation device  410  is buoyant enough to float on the surface of the swimming pool, even when apparatus  100  has been filled with chlorine tablets. Apparatus  100  is placed into swimming pool  400  at position 1 and, due to the combined mass of apparatus  100  and the chlorine tablets placed inside apparatus  100 , apparatus  100  will gradually sink to position 2. The length of flexible cord  420  is fixed so as to ensure that apparatus  100  will be suspended slightly above the floor of swimming pool  400  at position 2, thereby preventing apparatus  100  from contacting the bottom surface of swimming pool  400 . As previously explained, the chlorine tablets inside apparatus  100  will gradually dissolve and, due to the reduced mass, apparatus  100  will gradually rise towards the surface of swimming pool  400  until it reaches postion 3. Once apparatus  100  reaches position 3, the operator of swimming pool  400  will be visually notified that apparatus  100  has returned to the surface and apparatus can be filled with additional chlorine tablets and re-deployed. 
         [0030]    Referring now to  FIG. 5 , an cutaway exploded view of an apparatus  500  for chlorinating swimming pools in accordance with a preferred embodiment of the present invention is depicted. Apparatus  500  is similar to apparatus  100  of  FIG. 1 . As shown in  FIG. 5 , apparatus  500  has caps  110  and a body  120 . Additionally, floatation material  530  is contained within caps  110 . Floatation material  530  is a buoyant material (e.g., Styrofoam™) that provides the appropriate level of buoyancy for apparatus  500 . In the most preferred embodiments of the present invention, more floatation material  530  will be placed in one cap  110  than the other cap  110 . This configuration will ensure that, if desired, apparatus  500  remains in a substantially vertical orientation along its longitudinal axis. 
         [0031]    As shown in  FIG. 5 , one or more chlorine tablets  505  have been placed into body  120  of apparatus  500 . Additionally, one or more plugs  550  may be provided to plug one or more apertures  130 . By plugging one or more apertures  130 , the amount of water that enters body  120  can be controlled, thereby adjusting the amount of water that contacts the surface of chlorine tablets  505 . This allows the operator to increase or decrease the rate of dissolution for chlorine tablets  505 , to ensure that the rate of chlorination is always maintained at an optimal level for a given swimming pool. Spacers  510  may be positioned inside body  120  and between chlorine tablets  505  to hold tablets  505  in the desired orientation and position. End caps  520 , fitted with apertures  521 , may be used to hold chlorine tablets  505  and spacers  510  in position inside body  120 . In the most preferred embodiments of the present invention, spacers  510  may be circular disks with perforations, or simply “fingers” that extend from one edge of the interior space of body  120  to the other edge of the interior space of body  120 . Spacers  510  serve to keep chlorine tablets  505  in a vertical position (e.g., at approximately a 90° angle relative to longitudinal axis  250  of  FIG. 2 ). 
         [0032]    Referring now to  FIG. 6 , an alternative preferred embodiment of a cap or cap portion  110  is depicted. In this embodiment of the present invention, a plurality of capillary tubes  621  (e.g. straws) are positioned inside cap portion  110 . By varying the length of capillary tubes  621 , a desired amount of head space  630  (e.g. air pocket) may be maintained inside of cap  110 . This provides buoyancy for apparatus  100  of  FIG. 1  or apparatus  500  and may be used instead of floatation material  530  of  FIG. 5 . Additionally, one or more tubes  621  may extend above the uppermost part of cap  110 , thereby providing a conduit or pathway for chlorine to escape from the interior of body  120  into the surrounding water. 
         [0033]    Referring now to  FIG. 7 , a method  700  for chlorinating a swimming pool using an apparatus in accordance with a preferred exemplary embodiment of the present invention is depicted. As shown in  FIG. 7 , one or more chlorine tablets are placed inside the body of the apparatus (step  710 ). After the chlorine tablets are in place, the apparatus is placed into the swimming pool (step  720 ). Due to the combined mass of the apparatus and the chlorine tablets, the apparatus will gradually sink towards the bottom of the swimming pool until it reaches a point of near zero buoyancy close to the bottom of the swimming pool (step  730 ). 
         [0034]    Once in the water, the chlorine tablets in the interior space of the apparatus will gradually be dissolved via surface contact with the water in the swimming pool (step  740 ) and the chlorine from the dissolving tablet(s) will provide chlorination for the water in the swimming pool and, as that combined mass of the apparatus and the chlorine tablets is reduced, the apparatus will begin to rise towards the surface of the water (step  750 ). Once the apparatus is once again floating at or near the surface of the water, the operator of the swimming pool will be able to make visual contact with the apparatus and the cycle of method  700  can be repeated. 
         [0035]    From the foregoing description, it should be appreciated that an enhanced apparatus and methods for chlorinating swimming pools is provided by the various preferred embodiments of the present invention and that the various preferred embodiments offer significant benefits that would be apparent to one skilled in the art. Furthermore, while multiple preferred embodiments have been presented in the foregoing description, it should be appreciated that a vast number of variations in the embodiments exist. Lastly, it should be appreciated that these embodiments are preferred exemplary embodiments only and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description provides those skilled in the art with a convenient road map for implementing a preferred exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in the exemplary preferred embodiment without departing from the spirit and scope of the invention as set forth in the appended claims.