Abstract:
A whirlpool skimming device removes surface debris from a pool by creating a whirlpool having an upper bound at the surface of the pool. The uppermost portion of the whirlpool is free standing and is not bounded by the device. The device includes an outer cup-shaped portion and an inner cup-shaped portion coaxially disposed therein. An opening is disposed in the bottom of the inner cup-shaped portion which communicates with a source of suction which is preferably a Venturi tube feeding the outlet water to a filter bag. There is a first nozzle supplying water at an upper, inner edge of the inner cup-shaped portion at a slightly downward angle in a first direction, and there is a second nozzle supplying water at a lower, outer edge of the inner cup-shaped portion and mounted on an opposite side of the inner cup-shaped portion. The device causes coaxial rotational flow patterns relative to the inner cup-shaped portion, in which the outer rotational flow takes an upwardly spiral path outside the inner cup-shaped portion, and the inner rotational flow takes a downwardly spiral path inside the inner cup-shaped portion of the device.

Description:
CLAIM OF PRIORITY 
       [0001]    This patent application is a continuation in part, claims priority from, and hereby incorporates by reference U.S. patent application Ser. No. 13/136,987 titled “WHIRLPOOL SKIMMER” filed on Aug. 16, 2011. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to a device for skimming liquid and debris from the surface of a pool. 
       BACKGROUND OF THE INVENTION 
       [0003]    Pool cleaning devices are known in the prior art. For example, a skimmer and filter bag are shown in U.S. Pat. No. 5,919,359. 
         [0004]    A pool cleaning system with multiple cleaning heads is shown in U.S. Pat. No. 6,022,481. 
         [0005]    Further, a liquid surface skimmer with filter bag is shown in U.S. Pat. No. 6,027,641. 
         [0006]    A pool skimmer with filter bag and support is shown in U.S. Pat. No. 6,086,759. 
         [0007]    A telescopic arrangement is shown in a pool skimmer in U.S. Pat. No. 7,146,658. 
         [0008]    A canister filter for a swimming pool is shown in U.S. Pat. No. 7,384,544. 
         [0009]    A pool skimmer having a spray head is shown in U.S. Pat. No. 7,455,767. 
         [0010]    A circulatory swimming pool cleaning system is shown in U.S. Pat. No. 7,862,712. 
         [0011]    There is a need in the art for an efficient, effective pool cleaning device that is capable of readily removing debris such as leaves or insects from the surface of a pool. 
         [0012]    There is a need for such an efficient, effective pool cleaning device which is powered by water flow and does not need an external source of power. 
         [0013]    Further, there is a need for such an efficient, effective pool cleaning device which operates without requiring large amounts of water flow, and which can operate in conjunction with other pool cleaning equipment such as water pumps and water circulatory systems. 
       SUMMARY OF THE INVENTION 
       [0014]    From the foregoing, it is seen that it is a problem in the art to provide a device meeting the above requirements. According to the present invention, a device and process are provided which meets the aforementioned requirements and needs in the prior art. 
         [0015]    Specifically, the device according to the present invention is a whirlpool skimming device for removing surface debris from a pool, by creating a whirlpool having an upper bound at the surface of the pool and where the uppermost portion of the whirlpool is free standing and is not bounded by the device. 
         [0016]    The whirlpool skimming device according to the present invention removes surface debris from a pool by creating a whirlpool having an upper bound at the surface of the pool. The uppermost portion of the whirlpool is free standing and is not bounded by the device. The device includes an outer cup-shaped portion and an inner cup-shaped portion coaxially disposed therein. Open opening is disposed in the bottom of the inner cup-shaped portion which communicates with a source of suction. The source of suction is preferably a Venturi tube feeding the outlet water to a filter bag. There is a first nozzle supplying water at an upper, inner edge of the inner cup-shaped portion at a slightly downward angle in a first direction, and there is a second nozzle supplying water at a lower, outer edge of the inner cup-shaped portion and mounted on an opposite side of the inner cup-shaped portion. The second nozzle directs fluid in an approximately opposite direction relative to the first nozzle as viewed from the top of the device, and the second nozzle can be angled slightly downwardly. The first and second nozzles are supplied by tubes communicating with a source of water, and can optionally include valves in the tubes for adjustably controlling the amount of water flowing through the nozzles. 
         [0017]    The device of the present invention causes coaxial rotational flow patterns relative to the inner cup-shaped portion, in which the outer rotational flow takes an upwardly spiral path outside the inner cup-shaped portion, and the inner rotational flow takes a downwardly spiral path inside the inner cup-shaped portion of the device. It is believed that the rising outer rotational flow is an important feature of the present invention, which is believed—from inspection of the mass flows from the first and second jets - to narrow and focus the inner vortical flow of the inner rotational flow and thereby direct the force of the vortex above the topmost portion of the funnel portion to the surface of the pool. This beneficial and useful effect is achieved in the working embodiment when the topmost portion of the funnel portion is disposed below the water surface by a distance preferably ranging from one to four inches. 
         [0018]    Other objects and advantages of the present invention will be more readily apparent from the following detailed description when read in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is a top elevational view of a funnel portion of the device according to the present invention. 
           [0020]      FIG. 2  is a side schematic elevational view of the device according to the present invention, showing hydraulic connections as well as fluid flow through a Venturi section. 
           [0021]      FIG. 3  is a schematic side elevational view of the device of the present invention in operation in a pool, with a vortex or whirlpool caused by the device extending to the upper surface of the pool. 
           [0022]      FIG. 4  is an enlarged top elevational view of an inner cup-shaped portion with oppositely directed nozzles, with fluid flow indicated. 
           [0023]      FIG. 5  is a schematic side sectional view taken along line  5 - 5  of  FIG. 1 , showing the interior structure of the outlet portion of the device. 
           [0024]      FIG. 6  is a schematic side sectional view similar to  FIG. 5 , showing coaxial rotational flow patterns relative to the inner cup-shaped portion, in which the outer rotational flow takes an upwardly spiral path outside the inner cup-shaped portion, and the inner rotational flow takes a downwardly spiral path inside the inner cup-shaped portion of the device. 
           [0025]      FIG. 7  is a schematic view of the coaxial rotational flow patterns shown in  FIG. 6 , omitting the structural elements for the sake of clarity, in which the outer rotational flow takes an upwardly spiral path outside the inner cup-shaped portion, and the inner rotational flow takes a downwardly spiral path inside the inner cup-shaped portion of the device. 
           [0026]      FIG. 8  is a schematic top elevational view of the coaxial rotational flow patterns shown in  FIGS. 6 and 7 , schematically showing just the inner cup-shaped portion and the funnel portion, omitting other structural elements for the sake of clarity, in which the outer rotational flow is seen to flow in the same rotational direction as the inner rotational flow. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0027]      FIG. 1  is a top elevational view of a funnel portion  110  of a whirlpool skimming device  100 . The funnel portion  110  is generally cup-shaped with an inner, tapering funnel-shaped portion  120  terminating at an opening  140  formed in the lowermost portion of the inner, tapering funnel-shaped portion  120 . In this view, an inner cup-shaped portion  130  is generally coaxially disposed within the funnel-shaped portion  120  of the funnel portion  110 , and is open at its bottom so as to communicate with the opening  140 . 
         [0028]    As shown in  FIG. 1 , a pair of nozzles  150  and  160  are disposed adjacent the inner cup-shaped portion  130 , with the nozzle  150  being disposed adjacent the outside edge of the inner cup-shaped portion  130  while the nozzle  160  is disposed adjacent the inside edge of the inner cup-shaped portion  130 . Fluid flow from these nozzles is depicted in  FIG. 4  below. 
         [0029]      FIG. 2  is a side schematic elevational view of the whirlpool skimming device  100 , showing pipes  170  and  190  along with hydraulic connections  162  and  164 , and an inner coaxial pipe section  180  shown in dashed outline. Arrows F 1 , F 2 , and F 3  indicate the direction of fluid flow through the pipes  170 ,  180 , and  190 . The pipes  170 ,  180 , and  190  have a fluid flow which creates a type of Venturi effect to draw water or other liquid as a fluid flow F 2  through the opening  140  powered by the incoming fluid flow F 1  through the pipe  190 , while discharging the combined liquid as discharge flow F 3  through the open end of the pipe  170 . 
         [0030]    As shown in  FIG. 2  in dashed outline, the nozzle  160  is disposed adjacent an upper edge of the inner cup-shaped portion  130 , also shown in dashed outline. The nozzle  150 , shown in dashed outline, is disposed near a lowermost end of the inner cup-shaped portion  130 . The nozzle  150  is disposed along the outside of the inner cup-shaped portion  130 , while the nozzle  160  is disposed along the interior side of the inner cup-shaped portion  130 . A valve  163  is optionally disposed in the line  162  to regulate fluid flow, and a valve  165  is optionally disposed in the line  164 . The valves  163  and  165  can be omitted, and are not necessary to the present invention. 
         [0031]    The nozzles  150  and  160  are oppositely directed, so as to direct fluid flow either in a clockwise direction or in a counterclockwise direction. The nozzle  160  is preferably angled slightly downwardly a few degrees. The relative disposition of the nozzles  150  and  160 —both vertically and relative to the interior and exterior of the inner cup-shaped portion  130 —is important for the highly efficient vortex effect generated by the present invention. However, such disposition can be varied while still creating a vortex effect, albeit with less efficiency, and such variations would be understood by any one having skill in the hydraulic arts. 
         [0032]    The conduits  162  and  164  must pass through wall portions of the funnel portion  110 , and this preferably should be done to minimize the length of conduits  162  and  164  in the interior of the funnel portion  110  so as to avoid significantly disrupting the vortical flow. 
         [0033]    In  FIG. 2 , the lowermost edge of the inner, tapering funnel-shaped portion  120  is sealed against the lowermost edge of the inner cup-shaped portion  130 , such that no fluid can flow out of the bottom of the inner, tapering funnel-shaped portion  120  except via the uppermost opening of the inner cup-shaped portion  130 . This fluid flow is shown in  FIG. 3 . Thus, the fluid jet introduced by the nozzle  150  necessarily cannot exit except by rising. The fluid jet from the nozzle  150  causes a rising, spiral-shaped flow which—due to centrifugal force—presses against the interior wall of the tapering funnel-shaped portion  120 . All of the fluid flow from the funnel portion  110  of the whirlpool skimming device  100  is represented by the flow F 2 , and the total output flow including that introduced by the Venturi portion is F 3 , as shown in  FIG. 2 . 
         [0034]      FIG. 3  is a schematic side elevational view of the whirlpool skimming device  100  in operation in a pool  400 , with a vortex or whirlpool  300  caused by the device extending to the upper surface  410  of the pool. As seen in  FIG. 3 , an important feature of the present invention is that the uppermost edge of the funnel portion  110  of the whirlpool skimming device  100  lies a distance S below the surface of the pool  400 , so that the uppermost portion of the vortex or whirlpool  300  is not bounded in any way by the whirlpool skimming device  100 . 
         [0035]    The whirlpool skimming device  100  removes surface debris from a pool by creating a whirlpool having an upper bound at the surface of the pool. The uppermost portion of the vortex or whirlpool  300  is free standing and is not bounded by the device  100 . The vortex or whirlpool  300  is created by the vortical flow caused by the directed water jets from the nozzles  150  and  160  (either clockwise or anticlockwise) together with the suction created by the Venturi from the pipes  170 ,  180 , and  190  which draws the flow F 2  through the opening  140  in the funnel portion  110 . The liquid in the pipe  190  flows under pressure from a source of pressure such as a pump or a city water main supply, for example. 
         [0036]    Since the device would work to skim a liquid surface, it can also be used to clean oil slicks, or for industrial uses, and is not limited to use with water and is not limited to use with pools. 
         [0037]    As shown in  FIG. 3 , the flow through the device  100  exits through a filter bag  210  as shown by the arrows W, so that the leaves and insects, and other debris, are caught in the filter  210 . In  FIG. 3 , supports would be provided to keep the device  100  at the predetermined depth S below the surface; various supports are known in the mechanical support arts and in the swimming pool arts, such as mechanical arms, rigid pipes, floats, and anchors, among others. All such supports are contemplated as being within the scope of the present invention. 
         [0038]    While the drawings show that the source of suction is preferably a Venturi tube, the suction in the pipe  180  could instead be directly produced by a water pump hydraulically connected to the outlet of the pipe  180 . In that case, the pipes  170  and  190  could be omitted. 
         [0039]      FIG. 4  is an enlarged top elevational view of the inner cup-shaped portion  130  with oppositely directed nozzles  150  and  160 , with fluid flow jets from the nozzles indicated as G 1  and G 2  respectively. The funnel portion  110  is also indicated, and is not to scale but shown in reduced size for clarity of illustration. 
         [0040]      FIG. 5  is a schematic side sectional view taken along line  5 - 5  of  FIG. 1 , showing the interior structure of the device  100 . Here, the parts are as described hereinabove, and the space between the pipes  170  and  180  is shown and is indicated by numerals  196 ,  196 . The space  196  is an annular cylindrical volume through which the water flows that arrives via the pipe  190  (not shown in this view). A lowermost end  181  of the pipe  180  is well within the pipe  170  having a distal end  171 , and this feature is important to the production of the Venturi effect to draw water from the end  181  of the pipe  180 . The opening  140  is clearly seen in this view. 
         [0041]      FIG. 6  is a schematic side sectional view similar to  FIG. 5 , showing coaxial rotational flow patterns Z 1  and Z 2  relative to the inner cup-shaped portion  130 , in which the outer rotational flow Z 2  takes an upwardly spiral path outside the inner cup-shaped portion  130 , and the inner rotational flow Z 1  takes a downwardly spiral path inside the inner cup-shaped portion  130  of the device  100 . It is believed that the rising outer rotational flow is an important feature of the present invention, which is believed—from inspection of the mass flows Z 1  and Z 2 —to narrow and focus the inner vortical flow of the inner rotational flow Z 1  and thereby direct the force of the vortex above the topmost portion of the funnel portion  110  to the surface  410  of the pool  400 . This beneficial and useful effect is achieved in the working embodiment (discussed hereunder) when the topmost portion of the funnel portion  110  is disposed below the surface  410  by a distance preferably ranging from 1 to 4 inches. This is necessary for the usefulness of the vortex, since the topmost edge of the funnel portion  110  would tend to block the flow of water from the surface of the water, and such flow from the surface is necessary to carry leaves, insects, and other debris into the vortex  300 . 
         [0042]    It is important to keep the whirlpool skimming device  100  oriented so that the topmost edge of the funnel portion  110  lies in a plane parallel to the water surface  410 , so that the vortex  300  draws in leaves and debris. If the funnel portion  110  is tilted, the vortex  300  may become less effective; if the tilt is substantial the vortex can even drive away the floating leaves and floating debris rather than drawing them into the vortex  300 . 
         [0043]      FIG. 7  is a schematic view of the coaxial rotational flow patterns shown in  FIG. 6 , omitting the structural elements for the sake of clarity, in which the outer rotational flow takes an upwardly spiral path outside the inner cup-shaped portion, and the inner rotational flow takes a downwardly spiral path inside the inner cup-shaped portion of the device. 
         [0044]      FIG. 8  is a schematic top elevational view of the coaxial rotational flow patterns Z 1  and Z 2  shown in  FIGS. 6 and 7 , schematically showing just the inner cup-shaped portion  130  and the funnel portion  110 , omitting other structural elements for the sake of clarity. In this view, the outer rotational flow Z 2  is seen to flow in the same rotational direction as the inner rotational flow Z 1 . Thus, the rotational flows Z 1  and Z 2  are parallel and together initially form, and thereafter reinforce, the flow of water forming the vortex  300 . The flow outer rotational flow Z 2  is initially rising in the vertical direction as described hereinabove, and at some distance above the upper surface of the inner cup-shaped portion  130  the flow Z 2  may be pulled into the vortex  300  (shown by the dashed path in  FIG. 7  of the flow Z 2 ) to join the downward flow F 2  through the inner cup-shaped portion  130 . 
       Working Embodiment 
       [0045]    In a working embodiment, the dimensions of the parts are preferably as follows. The pipe  170  can be composed of standard PVC pipe with a 2 inch diameter, and the pipe  180  a similar pipe but with a 1.25 inch diameter. The pipe  190  is preferably similar to the pipe  170 , or can be larger or smaller, for example 1.5 inches, as long as it can supply a sufficient water flow. The diameter of the inner cup-shaped portion  130  is three inches in the working embodiment, while the diameter of the funnel portion  110  is nine inches in the working embodiment. The conduits  162  and  164  in the working embodiment are formed by flexible plastic tubing having a one-quarter inch diameter. The length of the funnel portion  110  is ten inches in the working embodiment, and the inner, tapering funnel-shaped portion  120  begins to taper at a point six inches below the uppermost edge of the funnel portion  110  as viewed in  FIG. 2 . The depth (length) of the inner cup-shaped portion  130  is four inches. 
         [0046]    The uppermost edge of the inner cup-shaped portion  130  in the working embodiment is spaced approximately 1.5 inches in a horizontal direction from the side of the funnel-shaped portion  120 , and the lowermost edge of the inner cup-shaped portion  130  is spaced approximately ⅛ inch in a horizontal direction from the side of the funnel-shaped portion  120 . These dimensions can be varied, and are merely exemplary of the working embodiment. The venturi portion of the pipe, i.e. the coaxially extending pipes  170  and  180 , have the following dimensions. The pipe  180  has an inside diameter of 1.25 inches and an outside diameter of 1 and 9/16 inches. The inside diameter of the pipe  170  is approximately 2.0 inches in the working embodiment. The inner pipe  180  may have a smooth outer surface or a threaded outer surface; in the working embodiment the outer surface is threaded. 
         [0047]    In use, the working embodiment has been tested with respect to distance of the uppermost edge of the funnel portion  110  below the water surface  410 . For an effective vortex  300  sufficient to perform the tasks of removing surface debris and leaves, the minimum distance below the water surface  410  should be about 1 inch, with an optimal depth ranging between about 1 inch to about 3 inches below the water surface  410 . The maximum depth for an effective vortex  300  is about 6 inches, with a weaker yet discernible vortex  300  existing even to depths of about 7 to 8 inches below the water surface  410 . 
         [0048]    The invention being thus described, it will be evident that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention and all such modifications are intended to be included within the scope of the claims.