Abstract:
A floating dispenser is provided for dispensing a solid, dissolvable water treatment chemical into ambient water. The dispenser includes a bucket having top and bottom ends, a top wall covering the top end, an opening for admitting ambient water into the bucket interior, and a floatation ring that keeps only the top end above water such that the interior is water filled when the dispenser floats. A basket is disposed in the interior of the bucket for carrying a solid, dissolvable water treatment chemical, such as calcium hypochlorite. The basket is buoyant and movable vertically toward the top wall of the bucket. The dispenser includes a refill indicator that indicates when most of a full load of said chemical has dissolved. The refill indicator includes a pair of tabs that are connected to the basket and slidably mounted in slots in the top wall. The tabs extend above the top wall when the buoyant basket floats upwardly, providing a visual indication of the need for a refill that can easily be seen from a side angle.

Description:
FIELD OF THE INVENTION 
     This invention generally relates to chemical dispensers, and is specifically concerned with a floating dispenser for dispensing a solid, dissolvable water treatment chemical into ambient water, such as a swimming pool. 
     BACKGROUND OF THE INVENTION 
     Devices for dispensing water treatment chemicals into swimming pools are known in the prior art. Many of these devices include a cylindrical housing for containing a single stack of dissolvable tablets of, for example, calcium hypochlorite. The upper end of the housing is circumscribed by a buoyant material so that the device floats in an upright orientation with its upper end above the water line when placed in a pool. One or more openings are provided at the lower end of the housing to allow ambient water to enter the housing, dissolve the tablets, and provide a stream of halogen solution that disinfects and otherwise treats the ambient water. 
     In operation, the size, number or path length of water-admitting openings in the housing of such dispensers is first adjusted to a size commensurate with the size of the pool or other body of water to be treated. Next, the solid, dissolvable water treating tablets are stacked or otherwise placed into the interior of the housing. Finally, the device is placed in the body of water. Ambient water circulates through the opening or openings in the lower end of the housing and dispenses a halogen solution at a rate consistent with the size of the pool or other body of water until all of the water treating chemical has dissolved. 
     While such devices have proven to be generally satisfactory for their intended purpose, the applicants have observed a number of areas in which improvement is desirable. For example, many of these floating devices provide no indication when a refill of water treatment chemical is due, which can result in a substantial hiatus in the treatment of the water. While one floating chemical dispenser is known wherein the buoyant housing lists over to one side when all of the water treatment chemical has dissolved, the visual signal is provided in an inelegant way which compromises the aesthetics of the device. While a skimmer-basket type chemical dispenser is known which includes a buoyant plate within a cylindrical container that floats to the top when all of the chemical is dissolved, the resulting visual signal (i.e. the portion of the plate visible through a top-mounted dispenser opening) is visible only within a narrow, vertical cone circumscribing a central axis of the cylindrical container. Hence such a signaling mechanism would be ineffective in a floating dispenser located in a central portion of the pool, as the signal generated would be difficult if not impossible to see from a side angle. Additionally, in all known prior art devices, no signal is generated until substantially all of the chemical has dissolved, thereby providing no “lead time” for refilling, which often results in a hiatus in the dispensing of the water treatment chemical. 
     Clearly, what is needed is a floating dispenser for dispensing water treatment chemicals that provides a visual indication that a refill of chemical is needed before all of the chemical has been dissolved. Ideally, the signal generated can be easily seen from all angles around the perimeter of the pool or other body of water. It would be desirable if the signal did not compromise the aesthetics of the device in the water. Finally, the dispenser should be easy to use and simple and inexpensive to manufacture. 
     SUMMARY OF THE INVENTION 
     Generally speaking, the invention is a floating dispenser for dispensing a solid, dissolvable water treatment chemical into a pool or other body of water. The dispenser includes a bucket having top and bottom ends, a top wall covering the top end, an opening for admitting ambient water into the bucket interior, and a floatation portion that keeps only the top wall above water such that the bucket interior is water filled when the dispenser floats. 
     The dispenser has a refill indicator including a pair of tabs that are connected to a basket disposed in the interior of the bucket that carries a solid, dissolvable water treatment chemical, such as calcium hypochlorite. The tabs are slidably mounted in slots in the top wall. The basket is buoyant and moves upwardly toward the top wall of the bucket upon the dissolution of an amount of water treatment chemical indicative of a refill condition. The tabs extend above the top wall when the buoyant basket floats upwardly toward the top wall, providing a visual indication of the need for a refill that can easily be seen from a side angle. In the preferred embodiment, the basket moves upwardly into engagement with the underside of the top wall when most of a full load amount of water treatment chemical has dissolved, for example 90% of the maximum load capacity of treatment chemical of the basket. The ability of the refill indicator to indicate that a refill condition is imminent before all the water treatment chemical has dissolved advantageously allows the operator to refill the dispenser before it becomes completely empty, thus avoiding any significant hiatus in water treatment. 
     The tabs and the slots in the top wall are slidably connected throughout the entire range of movement of the basket within the bucket, thereby providing the refill indicator with a high degree of mechanical reliability. Preferably, the bucket interior and the basket exterior have a non-round shape and a plurality of guide ribs on one that slidably interfit with elongated recesses on the other so as to insure alignment between these two components at all positions of the basket within the bucket, thereby preventing misalignment between tabs and the slots in the top wall and further enhancing the mechanical reliability of the refill indicator. 
     The floatation portion of the bucket may include a buoyant material, such as a polymeric foam, that surrounds the upper end of the bucket such that most of the mass of the dispenser below the top wall is submerged, and both the bucket and basket are shaped so that the center of mass of the dispenser is located along a central axis. The resulting buoyancy configuration causes the dispenser to float in a vertical orientation with the top wall always a little above the water line such that the indicator tabs of the refill indicator can always be easily seen, and further allows the dispenser to be self-righting when exposed to waves or other water turbulence. 
     The bucket may also include a bottom wall having an opening for admitting ambient water, and a flow adjustment mechanism that adjusts the size of the opening. Preferably, the flow adjustment mechanism provides a plurality of discrete sizes of the opening, and a tactile click associated with each opening size so the operator of the dispenser can easily select among the opening sizes without having to invert or turn the dispenser on its side, which could disadvantageously re-distribute the solid chemical in an unbalanced pattern within the basket. A screen mesh may be provided in the flow adjustment mechanism to prevent precipitates or particulates from the solid water treatment chemical from falling out of the dispenser and bleaching or otherwise harming the floor of the pool. 
     The top wall includes a detachably removable lid that provides access to the interior of the basket. The lid includes a covering member having a bayonet-type coupling that engages a complementary-shaped opening in the top wall with a tactile click when twisted into a secure position. The lid further includes a handle connected to the covering member at three points to allow the floating dispenser to be easily and securely carried by the handle without fear of breakage. 
     Finally, the dispenser may include snap-fit fasteners for securing the top wall to the top end of the bucket, thereby reducing both the time and expense associated with assembling the dispenser. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the floating dispenser of the invention from a top side angle; 
         FIG. 2A  is an exploded side view of the dispenser of  FIG. 1  along the line  2 - 2 ; 
         FIG. 2B  is an enlarged side, cross sectional view of the dispenser, illustrating the slidable connection between the tabs on the basket and the slots in the top wall of the bucket; 
         FIG. 3  is a perspective view of the floating dispenser from a bottom side angle, illustrating the flow control mechanism in exploded perspective view; 
         FIG. 4  is a top perspective view of the basket of the dispenser, illustrating in exploded form how the pair of floats that render the basket buoyant are attached thereto; 
         FIG. 5A  is a side cross sectional view of the dispenser after a full load of calcium hypochlorite tablets has been loaded into the basket, illustrating how the weight of the tablets presses the basket downwardly against the bottom wall of the bucket such that the tabs of the refill indicator are not visible, and 
         FIG. 5B  is a side cross sectional view of the dispenser after about 90% of the calcium hypochlorite tablets has dissolved, illustrating how the buoyant basket floats upwardly such that the tabs of the refill indicator visibly extend above the top wall of the bucket of the dispenser, signaling a refill condition. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference now to  FIGS. 1 and 2A , wherein like numbers designate like components throughout all of the several Figures, the floating dispenser  1  of the invention generally comprises a bucket  3  that contains a basket  4  for holding a solid, dissolvable pool treatment chemical such as tablets of calcium hypochlorite. 
     Bucket  3  has a top portion  5   a  that includes a radially protruding wall  8 . Wall  8  contains an elliptical ring  9  of a buoyant, water and chemical resistant polymeric foam, such as closed cell expanded polystyrene that functions as a floatation component when the dispenser is immersed in water. The bucket  3  further has a top wall  11  mounted over its top end  5   a  that includes a detachably removable lid  13 . The buoyancy and positioning of the ring  9  relative to the top wall  11  are selected so that when the dispenser  1  is placed in a pool or other body of water in a fully loaded condition, the dispenser  1  will float in an upright orientation with only the top wall  11  extending above the water line, the rest of the dispenser  1  being submerged. The inner rim  14  of the top wall  11  includes several pairs of wedge-shaped projections  15   a - c  (not all of which are shown) uniformly spaced around its perimeter. These wedge-shaped projections  15   a - c  are registrable with complementary-shaped openings  17  present on flanges  19   a - c  extending from the top of the wall  8 . The bucket walls  8  and flanges  19   a - c  are integrally formed from a resilient, high density polyethylene which is advantageously moldable, resistant to water, caustic chemicals and degradation from sunlight. The resulting resiliency of the flanges  19   a - c  causes the pairs of wedge-shaped projections  15   a - c  to snap-fit into the complementary-shaped openings  17  when the upper wall  11  is aligned with and pressed down over the top of wall  8 . Additionally, opposing bores  21   a,b  are present in end flanges  20   a,b  and are registrable with opposing bores  23   a,b  present in the inner rim  14  of the top wall  11 . To complete a secure attachment between the top wall  11  and the rest of the bucket  3 , expandable pins (not shown) are inserted through the bores  21   a ,  23   a  and  21   b ,  23   b.    
     The lid  13  of the top wall  11  includes a plate-shaped, circular covering member  27  that is detachably mountable within a circular opening  31  by way of a bayonet-type coupling  29 . Coupling  29  includes a detent  32  that provides a tactile and audible click when the lid  13  is turned into secure engagement with the circular opening  31 . Lid  13  further includes a handle  33  having three connecting struts  35   a - c  equidistantly positioned around covering member  27  as shown. The handle  33 , struts  35   a - c  and covering member  27  are preferably integrally formed from the same high density polyethylene as the bucket walls  8 . The provision of three struts  35   a - c  advantageously provides three points of secure contact between the handle  33  and covering member  27 , thus reducing the chance that the handle will break away from the covering member  27  as a result of the tensile loads applied to the handle during the carrying of the dispenser  1  or the torque loads applied during removal or attachment of the lid  13   
     Finally, as is best seen in  FIGS. 1 and 2B , top wall  11  includes a refill indicator  36  that provides a visual signal to the operator as to when the dispenser  1  requires a refill of a solid, dissolvable water treatment chemical carried by the basket  4 . Refill indicator  36  comprises pair of opposing slots  37   a,b  integrally connected to tab receivers  41   a,b  that extend down from the bottom surface of the top wall  11 . Tab receivers  41   a,b  each include elongated openings  42   a,b  of the same size and shape of the slots  37   a,b . Refill indicator  36  further comprises indicator tabs  69   a,b  that extend from the top rim  67  of buoyant basket  4  and are received in the elongated openings  42   a,b . The specific operation of the refill indicator  36  is discussed in detail hereinafter with respect to  FIGS. 5A and 5B . 
     With reference now to  FIG. 3 , bucket  3  further includes a bottom wall  44  where a flow adjustment mechanism  46  is centrally located. Flow adjustment mechanism  46  includes a circular, recessed wall portion  48  in the bottom wall  44  having alternating vanes  50  and openings  51 . A circular valve plate  53  is receivable over the circular recessed wall portion  48  and has a substantially identical pattern of vanes  54  and openings  55 . A hub  56   a  in the center of the valve plate  53  fits onto a journal  56   b  at the center of the recessed wall portion  48  to rotatably mount the plate  53  over the wall portion  48 . A screen mesh  57  (shown in  FIG. 2A ) is disposed over the circular, recessed wall portion  48  on the side that faces the inside of the bucket  3 . The screen mesh is preferably formed from an inert plastic material such as polypropylene  57  and prevents particulate calcium hypochlorite larger than about 0.025 inches resulting from the dissolution of the calcium hypochlorite tablets from falling through the openings in the flow adjustment mechanism  46  and bleaching the surface of the pool bottom. A detent pin  58  is provided on the outer periphery of the valve plate  53  that is registrable, in discrete “click” fashion, with five uniformly spaced detent holes  60  on the bottom wall  44 . The resulting five, discrete positions that the detent pin provides for the valve plate  53  correspond to a completely closed position where the vanes  54  of the plate  53  completely cover the openings  51 , three intermediate positions where the vanes  54  of the plate  53  partially overlap (to a diminishing extent) the openings  51 , and a completely open position where the vanes  54  in the plate do not overlap with the openings  51  in the bottom wall portion  48  and the openings  55  and  51  are mutually aligned with one another. Ribs  62   a - c  protrude from the bottom face of the valve plate  53  to facilitate the grasping and turning of the plate  53  by the operator of the dispenser  1 . Finally, valve plate  53  includes three flanges  63   a - c  uniformly spaced around its perimeter which are insertable into three slots  64   a - c  located around the perimeter of the circular, recessed wall portion  48  to form a bayonet-type joint between the plate  53  and the wall portion  48 . 
     With reference now to  FIG. 4 , the basket  4  of the dispenser  1  includes a top rim  67  onto which a pair of opposing tabs  69   a,b  are integrally connected to. Tabs  69   a,b  are preferably of a color different from the color of the top wall  11  to provide visual contrast therebetween. Tabs  69   a,b  are offset with respect to major axis A as shown, but are still located on the curved end portions of the rim  67 . Such offsetting facilitates assembly of the top wall  11  over the top end  5   a  of the bucket  3  by affording clear access, from the inside of the dispenser, to the pin-receiving bores  21   a,b  and  23   a,b  located along the major axis A of both the bucket  3  and the top wall  11 . Such positioning on the curved end portions of the rim  67  provides some curvature to the tabs  69   a,b  which in turn enhances their visibility when viewed at a side angle in alignment with the side edges of the tabs. Basket  4  further includes an oval-shaped side wall  72  which terminates in a figure-eight bottom wall  74 . Both the side wall  72  and bottom wall  74  includes a number of flow slots  76  to allow ambient water to flow freely through the basket  4 . To render the basket buoyant, a pair of floats  78   a,b  likewise formed from expanded polystyrene are provided on either side of the wall  72  at the bottom of the basket  4 . Each float  78   a,b  includes a recess  80   a,b  for receiving pins  82   a,b  integrally molded on the outer surface of the side wall  72 . The buoyancy of the floats  78   a,b  is carefully selected so that the basket sinks against the bottom wall  44  of the bucket  3  when a full load of calcium hypochlorite tablets is loaded therein, but floatingly rises against the underside of the top wall  11  when about 90% of the full load of tablets has dissolved in the ambient water. Finally, the side wall  72  of the basket  4  includes four elongated recesses  84   a - d  (of which only  84   b  is visible in  FIG. 4 ). These recesses  84   a - d  receive guide ribs  88   a - d  located at the bottom portion of the bucket (and shown in  FIG. 2A ) when the basket is placed into the bucket  3  prior to the installation of the top wall  11 . The co-action between the recesses  84   a - d  and the guide ribs  88   a - d  maintains the basket  4  in alignment with the interior of the bucket  3  during the operation of the dispenser  1 . 
     The operation of the dispenser will now be described with respect to  FIGS. 5A and 5B . In the first step of the operation, the lid  33  is removed from the circular opening  31  in the top wall  11 . Next, a full load of a solid, dissolvable water treatment chemical is loaded into the basket  4  by the operator. In this example, such a full load is constituted by two stacks  90  of calcium hypochlorite tablets  92 , wherein the diameter of each tablet  92  is substantially complementary in shape to one-half of the figure-eight shaped bottom wall  44  of the basket  4 . The lid  33  is re-installed over the circular opening by inserting and twisting the lid approximately one-quarter turn until the bayonet-type coupling makes an audible and tactile “click” that signifies that the lid  33  is securely engaged within the circular opening  31 . Net, the flow adjustment mechanism  46  is adjusted to one of the four settings corresponding to either a partial or complete opening of the openings  51  in the circular, recessed wall portion  48  of the bucket bottom wall  44 . The operator may make such an adjustment by grasping the ribs  62  on the valve plate  53  and turning the valve plate until the clicks produced by the detent pin  58  in the detent holes  60  inform the operator that the appropriate flow adjustment setting has been achieved. Such an adjustment may be conveniently accomplished “blind” without the necessity of turning the dispenser over, which could have the effect of re-arranging the tablets  92  in an unbalanced configuration. Next, the operator positions the loaded dispenser  1  in a pool or other body of water. The buoyancy and positioning of the expanded polystyrene ring  9  causes the dispenser, when placed in a pool or other body of water in a fully loaded condition, to float in an upright orientation with only the top wall  11  and perhaps a small amount of the upper end  5   b  of the bucket to extend above the water line  95 , the rest of the dispenser being submerged. The buoyancy and positioning of the ring  9 , in combination with the uniform distribution of the tablets  92  with respect to both the major and minor axes of the dispenser  1 , further renders the dispenser self-righting when exposed to waves or other sources of turbulence in the pool. 
     As is specifically shown in  FIG. 5B , when about 90% of the full load of tablets shown in  FIG. 5A  dissolves, the buoyancy of the floats  78   a,b  of the basket  4  overcomes the weight of the remaining solid chemical contained therein, and causes the basket to vertically rise distance D within the bucket  3 . Consequently, the tabs  69   a,b  of the refill indicator  36  slidably move from their position flush with the upper wall  11  to a position above the upper wall, where they provide a visual indication to the operator of a refill condition. The aforementioned color contrast between the tabs  69   a,b  and the top wall  11  renders the signal easier to see. As indicated previously, a smooth and reliable slidable movement between the tabs and the slots  37   a,b  in the top wall is insured by the combination of the tab receivers  41   a,b  shown in detail in  FIG. 2B  and the cooperation between the elongated recesses  84   a - d  in the basket  4  and the ribs  88   a - d  in the interior of the bucket  3 . It should be noted that the refill indicator will give the operator the same amount of time to refill the dispenser  1  if a less than full load of tablets  92  is placed into the basket  4 . The ability of the refill indicator to generate a visual signal indicative of a refill condition before all of the tablets  92  have been completely dissolved advantageously allows the dispenser to treat water substantially continuously without any significant hiatus. 
     Different modifications, additions, and variations of this invention may become evident to the persons in the art. For example, the indicator tabs  69   a,b  may be of any one of a number of different shapes, and different mechanisms between the basket and the bucket may be used to convert the vertical, floating movement of the basket  4  within the bucket  3  into a visual signal. Also, the solid, dissolvable water treatment chemical is not confined to calcium hypochlorite, and may be any one of a number of different water treatment compounds. All such variations, additions, and modifications are encompassed within the scope of this invention, which is limited only by the appended claims, and the equivalents thereto.