Abstract:
A bathtub whirlpool toy and educational device has a bottom and gasket designed to allow the device to fit over the drain of a household fixture such as a bathtub or sink. The device has a generally cylindrical interior space having inlet slots set at an angle, so that water entering the interior from the bath will begin to rotate immediately. A central outlet leads to a recuperation chamber having an offset recuperation chamber outlet allowing the recuperation chamber outlet to sit directly over a bathtub drain. The recuperation chamber may have a plurality of vanes/fins designed to reduce water circulation and increase water flow. An adapter may allow the user to alter the size and shape of the interior space outlet aperture, and may be fixable in place or movable during use so as to allow the user to alter the vortex/whirlpool dynamically.

Description:
COPYRIGHT NOTICE 
     A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. 37 CFR 1.71(d). 
     CROSS-REFERENCE TO RELATED APPLICATIONS 
     N/A 
     FIELD OF THE INVENTION 
     This invention relates generally to toys, and specifically to bathtub toys. 
     STATEMENT REGARDING FEDERALLY FUNDED RESEARCH 
     This invention was not made under contract with an agency of the US Government, nor by any agency of the US Government. 
     BACKGROUND OF THE INVENTION 
     Toys for bathtub use tend to fall into a small number of types. There are floating devices such as rubber ducks. There are squirting devices like squirt guns. There are small numbers of animals which absorb water to expand from a tiny size to a small size. However, there are a limited number of scientific toys. 
     Scientific toys for the bath tend to be demonstrations of buoyancy: submarines and the like. One typical item would be U.S. Pat. No. 4,206,565 issued Jun. 10, 1980 to Goldfarb. 
     The applicant is unaware of any prior art relevant to the concept of a bathtub whirlpool toy. Searching in the database of the United States Patent and Trademark Office reveals numerous references to “whirlpool bathtubs”, which are not toys at all but rather bathtubs with jets to provide a massage to a user of the tub. U.S. Design Pat. No. D428,155 issued to Chalberg et al Jul. 11, 2000 is an example of this, as is U.S. Design Pat. No. D310,717 issued to Heiligenstein on Sept. 18, 1990. 
     Another irrelevant category of items concerns water park and amusement park rides. A number of such devices have whirlpools, waves, tubes or the like. U.S. Pat. No. 5,616,083 issued to Subbaraman et al on Apr. 1, 1997 is an example of this, as is U.S. Pat. No. 586,718 issued Jul. 20, 1897 to Wharton, Jr. 
     Another un-related category of items are devices for use in creating an air vortex using a fan, air jets, and similar items. U.S. Pat. No. 5,096,467 issued to Matsui on Mar. 17, 2002 is an example of this. 
     Yet another type of item un-related to the toy field is material handling apparatus for scientific or production work, for example, U.S. Pat. No. 3,372,873 issued to Weiss on Mar. 12, 1968. 
     Finally, a number of display items having clear cylindrical sides and machinery for creating a whirlpool in a standing body of liquid within the cylinder are known. None of these relate to bathtubs, drain powered vortexes or the like. Examples include: U.S. Pat. No. 4,258,912 issued Mar. 31, 1981 to Reighart, II and U.S. Pat. No. 5,272,604 to Lin on Dec. 21, 1993, and U.S. Pat. No. 6,241,359 issued Jun. 5, 2001 to Lin and U.S. Pat. No. 6,295,749 issued Oct. 2, 2001 to Lin and U.S. Pat. No. 6,681,508 issued Jan. 27, 2004 to Unger et al. 
     None of these devices teach that an ordinary, non-jetted bathtub drain may be used to power a whirlpool for education and amusement of children. 
     None of these devices teach a cylindrical body having a drain dimensioned and configured to sit atop a household bath or sink drain, a recuperation chamber, a gasket sized to secure the device to a bathtub surface, and a hole having liquid access to a household drain. 
     SUMMARY OF THE INVENTION 
     General Summary 
     A bathtub whirlpool toy and educational device has a bottom and gasket designed to allow the device to fit over the drain of a household fixture such as a bathtub or sink, even though such drains may be set quite close to the edge of the bathtub, and most bathtubs do not have flat bottoms. 
     The device has a generally cylindrical interior space with a clear or open top, and further having inlet slots set at an angle, so that water entering the interior from the bath will begin to rotate immediately upon entrance. A centrally placed outlet in the bottom of the interior space leads to a recuperation chamber having an offset recuperation chamber outlet allowing the recuperation chamber outlet to sit directly over a bathtub drain and thus allowing water to exit the recuperation chamber directly to the bathtub drain. The recuperation chamber may have a plurality of vanes/fins designed to recover rotational kinetic energy content within the vortex, thus reducing the resistance to the flow of liquid within the toy, which in turn increases the flow rate and the size of the whirlpool formed. 
     An optional adapter may allow the user to alter the size and shape of the interior space outlet aperture, and may be fixable in place or movable during use so as to allow the user to alter the vortex/whirlpool dynamically. The adapter may have a shield portion blocking a portion of the vortex and an arm portion allowing the adapter to be moved or adjusted while a vortex/whirlpool is in progress. The arm portion may bend upwards, may pass through an inlet slot, or may pass through a special arm adjustment slot in the side of the side walls of the cylindrical interior. 
     Summary in Reference to Claims 
     It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide whirlpool toy for use in a partially enclosed household fixture having water therein and having a drain, the whirlpool toy comprising:
         a generally cylindrical body having a first generally cylindrical interior space, the body having a top allowing a clear view of the first interior space and at least one generally vertical side wall;   a first outlet aperture in a bottom of the first interior space, the first outlet aperture located near a center of the bottom of the first interior space;   a first recuperation chamber connected to the first interior space by the first outlet aperture, the first recuperation chamber having an open bottom of the first recuperation chamber offering a flow connection to the exterior of the device; and   at least one inlet slot extending vertically up a substantial portion of the at least one generally vertical side wall.       

     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the first recuperation chamber further comprises:
         fins located within the first recuperation chamber and disposed so as to produce turbulent flow of water within the first recuperation chamber, whereby flow out of the first recuperation chamber is increased.       

     It is therefore yet another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the inlet slot further comprises:
         first and second edges of the slot, wherein the first edge is set further from a center of the interior space than the second edge, whereby the slot is disposed at along a chord line of the generally cylindrical body, whereby water entering the first interior space from such household fixture does not move in a straight line towards the center of the interior space.       

     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy, wherein the cylindrical side wall and the inlet slot and the bottom of the first interior space are substantially smooth, whereby water moving within the first interior space travels in a laminar flow. 
     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy further comprising:
         at least one gasket dimensioned and configured to secure the device to the bottom of such household fixture.       

     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the first recuperation chamber is located, dimensioned and configured to offer unimpeded water flow from the first recuperation chamber to such drain. 
     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the first recuperation chamber is defined by the bottom of the first interior space and the side wall of the body. 
     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the top allowing a view of the interior of the device further comprises: an open top. 
     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the top allowing a view of the interior of the device further comprises: a transparent top. 
     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy further comprising:
         a vortex control adapter having a hand grip extension, a shield disposed at end of the hand grip extension, and at least one shield aperture passing through the shield, the shield being larger than the first outlet aperture and the first shield aperture being smaller than the first outlet aperture.       

     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the vortex control adapter further comprises: a second shield aperture passing through the shield, the second shield aperture being a different size than the first outlet aperture. 
     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy, wherein the edges of the slot are substantially streamlined to reduce turbulent flow. 
     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the inlet slot further comprises:
         at least one entry vane directing water flowing through the inlet vane in a direction substantially perpendicular to the center of the first interior space.       

     It is therefore another aspect, advantage, objective and embodiment of the invention to provide a whirlpool toy wherein the hand grip extension further extends a sufficient distance to extend out of the first interior space, whereby the user may manipulate the adapter while the toy is generating a vortex. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partially transparent perspective view of a first embodiment of the device. 
         FIG. 2  is a perspective view of the first embodiment in use in a household fixture such as a bathtub. 
         FIG. 3   a  is a cross-sectional diagram of a second embodiment of the device, showing a preferred water flow and a first possible vortex pattern. 
         FIG. 3   b  is a cross-sectional diagram of a third embodiment of the device, showing an undesirable water flow and a second possible (desirable) vortex pattern. 
         FIG. 4  is a cross sectional diagram of a fourth embodiment of the device, showing details of the recuperation chamber. 
         FIG. 5  is partially transparent bottom view of the device showing details of a fifth embodiment and the recuperation chamber. 
         FIG. 6  is a planform view of an adapter according to the device, allowing interactive and dynamic user control of the vortex. 
         FIG. 7  is a perspective view of a seventh embodiment of the device. 
         FIG. 8  is a side view of an eighth adapter embodiment of the device, showing details of the device. 
         FIG. 9  is a perspective view of a ninth adapter embodiment of the invention, showing details of the adapter. 
         FIG. 10  is a bottom planform view of a tenth embodiment recuperation chamber. 
         FIG. 11  is a bottom planform view of an eleventh embodiment recuperation chamber. 
     
    
    
     INDEX OF THE REFERENCE NUMERALS 
     
         
         Device  100   
         Lower recuperation chamber  102   
         Inlet slot  104   
         Slot wall  106   
         Lip/gasket  108   
         Recuperation fin/vane  110   
         Interior space outlet aperture  112   
         Desirable vortex flow  114   
         Inlet flow  116   
         Upper vortex chamber wall  118   
         Household fixture  202   
         Bottom of household fixture  204   
         Device  206   
         Device/sidewall with gasket  304   
         Recuperation/lower chamber  306   
         Interior space outlet aperture  308   
         Household fixture drain  310   
         Water  312   
         Possible vortex  314   
         Possible vortex  320   
         Household fixture bottom  322   
         Side wall  402   
         Interior space  404   
         Top  406   
         Inlet slot  408   
         Inlet slot edges  410 ,  412   
         Interior outlet aperture  414   
         Interior bottom  416   
         Recuperation chamber  418   
         Recuperation vane/fin  420   
         Household fixture bottom  422   
         Gasket  424   
         Household fixture drain  426   
         Recuperation chamber  502   
         Side wall of recuperation chamber  504   
         Interior outlet aperture  506   
         Vanes  510   
         Adapter shield  602   
         Adapter shield hand grip extension  604   
         First aperture  606   
         Second aperture  608   
         Third aperture  610   
         Interior space  702   
         First side wall  704   
         Second side wall  706   
         Interior bottom  708   
         Inlet slots  710 ,  712   
         First slot edge  714   
         Second slot edge  716   
         Gasket  722   
         Aperture  800   
         Lip  802   
         Adapter handle extension  804   
         Aperture and lip  900   
         Shield  902   
         Handle extension  904   
         Interior outlet aperture  1000   
         Vane/fin  1002   
         Gasket/lip  1004   
         Recuperation outlet aperture  1006   
         Flow  1008   
         Interior outlet aperture  1100   
         Vane/fin  1102   
         Gasket/lip  1104   
         Recuperation outlet aperture  1106   
         Flow  1108   
       
    
     DETAILED DESCRIPTION 
       FIG. 1  is a partially transparent perspective view of a first embodiment of the device  100 . Lower recuperation chamber  102  and upper recuperation chamber (defined by wall  118 ) are separated by a floor into two different chambers, connected only by interior space outlet aperture  112 . A vortex may be easily formed in the upper chamber, while the lower chamber (defined by the bottom of the bathtub and the bottom of the interior vortex chamber) aids in speeding flow and preventing water from developing undesirable back pressure by means of recuperation fin/vane  110 , which recovers kinetic energy from the vortex. 
     Inlet slot  104  is defined by inner slot wall  106  and accepts inlet flow  116 , water which comes in from a large sink or bathtub partially full of water. Inner slot wall  106  channels and directs the flow to produce a desirable vortex flow  114 . 
     Lip/gasket  108  helps seal the recuperation chamber from the ambient water in the household fixture so as to aid in preventing water from bypassing the upper chamber. 
       FIG. 7  is a perspective view of a first embodiment of the device. In this perspective view, the center of the bottom, and the outlet therefrom is not visible, nor is the recuperation chamber located thereunder. 
     Interior space  702  has interior bottom  708  and first and second side walls  704 ,  706 . Interior bottom  708  and side walls  704 ,  706  define the interior space, which is generally a regular cylinder having a round planform. (In alternative embodiments, the interior space could conceivably be shapes other than a circular column, such as an elliptical planform, or a frustum or conical shape, so long as water flow in enhanced by the shape.) Thus the overall device takes on the aspect of an open topped or clear topped barrel. The body of the device may be molded of plastic or other polymer, made of metal, wood, composites and other similar materials. The materials selected may be wholly or partially transparent. 
     Inlet slots  710 ,  712  allow water to flow into the interior space  702  from the water-filled household fixture in which it is placed. Inlets  710 ,  712  are defined by edges such as first slot edge  714  and second slot edge  716 . It will be seen that the slot edges  714 ,  716  may be streamlined in shape so as to promote smooth water flow within the device in order to minimize pressure loss within the inlet vanes and promote even flow within the upper chamber. Importantly, slots  714 ,  716  may be set at an angle to the straight radial path to the center (not seen in  FIG. 1 ) of the interior space. The angle of the slots will make a chord with the overall circular planform of the device, so water entering the device will enter traveling sideways, and the slots will tend toward the exact orthogonal so as to provide the largest angle possible to the flow within the barrel shaped interior space. Any number of such slots may be used, and the size and placement may be varied. The slots may also take the form of rows of apertures or rows of jets, which rows may be arrayed either vertically or horizontally or a combination of both, and this definition of slot is specifically included within the scope of the invention. 
     Handles may provide a convenient grip on other alternative embodiments of the device, and may further provide a location at which a lanyard, string, chain or the like may be secured. 
     Gasket  722  may be a relatively soft and conformable material which allows the device to conform to the bottom of typical household water fixtures like sinks and bathtubs. The conformance to the shape of the bottom of the bathtub or sink is important so as to force water exiting the fixture to pass through the device. 
     It will be appreciated that the dimensions of the device, especially the height and width, will alter the characteristics of the vortex created therein. For a single example, greater height provides a greater “head” of pressure to generate sideways motion and the vortex. It will be appreciated that the dimensions of the slots will dramatically alter the characteristics of the vortex in a similar manner. 
       FIG. 2  is a perspective view of the first embodiment in use in a household fixture such as a bathtub. Household fixture  202  may have a bottom of household fixture  204 , which may not be entirely flat nor regular. Device  206  may be set into the fixture at a location over the drain from the device (drain not seen due to device  206 ). It will be appreciated that the central axis of the generally cylindrical device may be offset from the drain of the bathtub, thus allowing formation of a wider body and vortex within. 
     In use, the fixture is filled with water and the drain is opened. Gaskets and the body of the device  206  will impede water from directly exiting via the drain, and force it through the slots/apertures on the side of the device at which point, the laminar and rotating water within the device will swiftly organize into a well defined vortex, a result confirmed by testing. 
       FIG. 3   a  is a cross-sectional diagram of a second embodiment of the device, showing a preferred water flow and a first possible vortex pattern, while  FIG. 3   b  is a cross-sectional diagram of a third embodiment of the device, showing an undesirable water flow and a second possible (desirable) vortex pattern. Device/sidewall  304  defines both the upper/vortex interior space and also lower recuperation chamber  306 , which recuperation chamber is fed by water flowing out from interior space outlet aperture  308 . Water may then exit the recuperation chamber  306  via the recuperation chamber&#39;s open bottom, or via any opening if the chamber has a bottom with an aperture. A bottom of the chamber is felt to be less desirable in terms of forming a large vortex, as an open bottom would appear to offer the best possible flow. A gasket may be provided on sidewall  304  or may be omitted, depending on embodiment, construction techniques and materials of the sidewall and other considerations. 
     Water flow paths are crucial to the invention. Water  312  may have within it either possible vortex  314 , possible vortex  320 , or any other myriad shapes including vortices which are not straight (see vortex  314 ) or are conical (vortex  320 ), and so on. 
     Water flow arrows mark desirably speedy water flow from the recuperation chamber  306 . It will be understood that slow moving water near or at the first aperture (the interior space outlet/recuperation chamber inlet  308 , that is, the aperture in the bottom of the interior space and the top of the recuperation chamber) will impede the flow of water in the interior chamber, which water  312  desirably moves quite quickly. Thus undesirable water flow may in embodiments be avoided: swirling water in the recuperation chamber should have the energy removed so that it quickly exits via household fixture drain outlet  310 . The household fixture bottom  322  may define the bottom of the recuperation chamber  306 . 
       FIG. 4  is a cross sectional diagram of a fourth embodiment of the device, showing details of the recuperation chamber. Side wall  402  defines interior space  404  having top  406 . In the presently preferred embodiment and best mode now contemplated, top  406  is an opening allowing users to experiment and play with the vortex, for example by feeling it, placing water toys into it, or using an adapter (explained in reference to  FIG. 6 ) in a dynamic/interactive mode. In alternative embodiments, however, top  406  may be transparent, a smaller aperture, screened and so on. 
     Inlet slot  408  is defined by inlet slot edges  410 ,  412 , while interior outlet aperture  414  may be clearly seen in the center of the interior bottom  416 . The interior outlet aperture  414  may be placed at locations other than the center of the interior bottom  416  (that is, locations away from the center of the interior space  404 ) in alternative embodiments. 
     Recuperation chamber  418  (again defined by household fixture bottom  422 ) may have therein vane/fin  420  or a plurality thereof, which may function to remove kinetic energy from the water entering the chamber via aperture  414 . Water may then flow more quickly to household fixture drain  422  and thus may exit more rapidly. 
     Gasket  424  may be seen more clearly as well. Note that the gasket  424  may in embodiments be eliminated, if the material of the device or the shape of the device allows a workable seal with the bottom of the bathtub/fixture. 
     It may be seen once again that the bathtub drain may be offset from the drain of the interior space/vortex chamber, and that the bathtub surface combines with the side walls of the body and the bottom of the vortex chamber to define the recuperation chamber. 
       FIG. 5  is partially transparent bottom view of the device showing details of a fifth embodiment and the recuperation chamber. Recuperation chamber  502  is defined by side wall of recuperation chamber  504  and has interior outlet aperture  506  (which of course functions as an inlet for the recuperation chamber  502 ) and further has recuperation outlet aperture  508 . Vanes/fins  510  may be straight and still function to recover kinetic energy from the water, or may be shallow curves, angled, bent and other shapes. Fins as used herein includes patterns of posts or pins, bumps, ridges, irregularities, and so on. The vanes/fins may extend entirely across the chamber from top to bottom, or may extend partially from either the top or bottom of the chamber, or may extend from the sides or center of the chamber, may be irregular, and may vary in number. 
       FIG. 6  is a planform view of an adapter according to the device, allowing interactive and dynamic user control of the vortex. 
     Adapter shield  602  may be a three dimensional shape or, as in the best mode now contemplated, may be substantially flat, and somewhat larger in size (radius) than the size (radius) of the interior space outlet aperture, on which it may optionally sit. Adapter shield hand grip extension  604  may allow easy manipulation of the adapter shield, especially during the time a vortex is actually being generated, so that the user may move the base of the vortex, switch to a smaller or larger opening or switch to an opening of different shape. Extension  604  may pass through one of the device&#39;s water inlet slots or may pass through a special slot made for the extension in the side walls of the body of the device. 
     First aperture  606  and second aperture  608  may be different sizes and may be different sizes (radii) from the size (radius) of the outlet aperture. Third aperture  610  may be a different shape than other apertures. In embodiments, the adapter may “plug in” or be otherwise secured in place in the bottom of the interior space. In such embodiments, the extension may be omitted, and the device may screw in or have attachments to secure it to the interior bottom. 
     Screens may be employed at diverse locations within the device, for example at the top, at the apertures, or as a bottom of the recuperation chamber, at the inlet slots and so on. 
     The device may have an “open bottomed” recuperation chamber, that is, the recuperation chamber may have no bottom, allowing water which flows into the recuperation chamber via the interior space outlet aperture to fall directly to the bottom of the bathtub. 
       FIG. 8  is a side view of an eighth adapter embodiment of the device, showing details of the device aperture  800 , which may have a lip  802  or gasket  802  allowing the aperture to be loosely seated within the interior space outlet aperture, whereby motions of the adapter handle extension  804  may move the vortex about. A gasket as the lip forces a larger portion of the water to pass through the vortex in order to escape the interior space. 
       FIG. 9  is a perspective view of a ninth adapter embodiment of the invention, showing details of the adapter. Aperture and lip/gasket  900  penetrate shield  902 , which otherwise blocks exit of the water. Handle extension  904  may be as previously discussed. 
       FIG. 10  is a bottom planform view of a tenth embodiment recuperation chamber, and  FIG. 11  is a bottom planform view of an eleventh embodiment recuperation chamber. Interior outlet apertures  1000 / 1100 , gasket/lip  1004 / 1104 , and household fixture drain  1006 / 1106  may be substantially as previously described in reference to  FIGS. 1 through 9 . However, it may be seen that vane/fin  1102 / 1002  may arc in two different directions, resulting in flow  1008 / 1108  going in either one of two different directions, depending upon the embodiment. It is obvious that different rates of drainage from the recuperation chamber may be achieved in this way, with resulting differences in back pressure and thus differences in the flow and vortex in the interior space (not shown). 
     The disclosure is provided to allow practice of the invention by those skilled in the art without undue experimentation, including the best mode presently contemplated and the presently preferred embodiment. Nothing in this disclosure is to be taken to limit the scope of the invention, which is susceptible to numerous alterations, equivalents and substitutions without departing from the scope and spirit of the invention. The scope of the invention is to be understood from the appended claims.