Abstract:
This circulation device is equipped with a water impeller that is larger than and tightly fitted over the top of the draft tube through which the water from the pond or reservoir is drawn. The water drawn up and directed outwardly over a large diffuser plate that is centrally located within the invention. The outer edge of the diffuser plate is equipped with a laminar flow diffuser lip which is specifically designed to inhibit the passage of water from the diffuser plate to the open water as little as possible. Additionally, a means of providing a floating water circulation apparatus with the ability to operate effectively in weather conditions in which a layer of ice is likely to form over the diffusor plat of the apparatus in the nighttime hours is provided.

Description:
This application is continuation-in-part of Ser. No. 09/315,736 filed May 20, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a circulation system for a body of liquid. More specifically, to a floating system for exchanging or displacing water or other liquids from lower levels and delivering them to the upper surface to allow for maximum exposure to the atmosphere. 
     In order for many bodies of water to develop and maintain a healthy eco-system, a non-specific amount of circulation is typically required. This is because many of the bacteria that are necessary for breaking down or digesting nutrients are immobile, and therefore, need to be placed in intimate contact with nutrients, necessary to thrive, by circulation of the water. Furthermore, in the majority of applications, bacteria also need oxygen to survive and flourish. The most readily available source of oxygen is from the atmosphere. 
     Oxygen can enter the water through contact with the atmosphere which may be accelerated through mixing, as happens in nature through waterfalls, streams, rain, and wind. It has been found that adding artificial aeration, to assist nature, to natural and man made ponds and lagoons can greatly increase the health of the ponds. This may be especially useful in sewage lagoons and the like as the decay process could be accelerated and unpleasant smells reduced. 
     In order to combine the movement of liquid and supplying of the oxygen, past prior art has typically used one of three methods: (1) a surface splashing action (2) an aspirator/boat prop effect which draws atmospheric air in and then forces air bubbles out or (3) compressing atmospheric air and then releasing it at the bottom of the body of liquid. In each of these actions two things are readily apparent (A) high energy input with corresponding high maintenance needs and (B) the action created is always turbulent. 
     The use of pond aerators on floating bases has been well establishe such as those shown by U.S. Pat. No. 4,179,243 granted to Aide and U.S. Pat. No. 4,030,859 granted to Henager. In these patents, devices are typically supplied with a draft tube placed just below the surface of the water. This tube houses a propeller or impeller that is connected to a drive means. A draft line is placed at a predetermined depth and connected to the draft tube. Thus, as the drive means turns, the impeller or propeller draws water from a certain depth and defuses it at the water surface. This process circulates and turns the water in the pond. As power to the pump can be a significant issue in remote areas, such as the middle of a pond or lake, the efficiency of the whole unit is crucial to its success. This has required that alternative means of driving the pump on pond mixers would be desirable. One solution has been to use wind power, however wind powered pumps are large in size, expensive, cumbersome, and create a need for complex and expensive anchoring systems. 
     From this discussion it can be seen that a low energy, circulation method is needed. Such a method or device should be designed to gently circulate (vs. turbulent mixing) a liquid from bottom-to-top with a minimum amount of energy and deliver that liquid to a major oxygen source (the atmosphere) in a manner which will maximize atmospheric absorption. Further it would be advantageous to make such a system so that it can be driven by an inexpensive renewable resource, and thus, able to be used in remote areas with a minimal amount of setup. 
     SUMMARY OF THE INVENTION 
     It is the primary objective of the present invention to provide a method of circulating bodies of water in a highly efficient manner that allows for the use of an extremely low horsepower pump. 
     It is an additional objective of the present invention to provide a method of circulating bodies of water and thus, increase their exposure to the atmosphere through the use of an alternative source of power, such as relatively small solar panels. 
     It is an additional objective of the present invention to combine these characteristics in a small, floating, portable device that can be placed in a desired location and left to circulate a liquid from a lower elevation to the surface. 
     It is an additional objective of the present invention to provide a method of delivering liquid, through a distribution dish or diffusor, in a non-turbulent manner that will maximize the amount of time the liquid remains on the surface. 
     It is an additional objective of the present invention to provide a means by which a water circulation apparatus can be used to constantly circulate a body of water during times where the surface of the body of water is prone to freezing during the nighttime hours which, with current water circulation apparatuses, tends to block the distribution of water from the diffusor of the apparatus to the surface of the body of water which in turn blocks circulation. 
     It is a further objective of the present invention to provide a such a method of anchoring such devices that will allow a water circulating device to ride up and down on the water&#39;s surface waves while being-subjected to continuously alternating cycles of tug and slack in high wind conditions without interfering with its floatation characteristics or its ability to move under normal weather conditions. 
     It is a still further objective of the present invention to provide such a water circulation apparatus which has a water pick up system that is designed in such a way so that the water pick up tube will not get tangled with the anchor line while the circulation apparatus is drifting around the surface of a body of water. 
     These objectives are accomplished by the use of a floating circulation apparatus that has as an on-board power system. This on-board power system may consist of a plurality of solar panels that produce the entirety of the power required to drive the water pump, however other power such as wind, electrical, gas or others may be used. This circulation device is equipped with a water impeller that is larger than, and tightly fitted over, the top of the draft tube through which the water from the pond or reservoir is drawn. By placing the impeller above and out of the draft tube, the efficiency of the pump will be greatly increased. Thus, the same amount of horsepower will move a much larger amount of liquid. 
     By having the impeller up and out of the draft tube, it is also possible to impart movement to the water in two different ways. First, the impeller moves water by a lifting action which is caused by the rotation of the auger-like impeller. Second, the impeller imparts a rotating motion to the water. This rotating motion will generate centrifugal force, causing even more water movement or mixing. Prior art circulation devices place the impeller down in the draft tube and thus, the rotating motion of the water is wasted as the water is trapped by the walls of the draft tube. 
     The present invention is also equipped with a large flow distribution or diffuser dish surrounding the impeller. The size and shape of the impeller works to allow the water to move directly away from the impeller, radially. Additionally, the flow diffuser is also equipped with a specially designed outer edge which does not impede the radial flow of water created by the impeller as it passes from the diffuser to the surface of the lake or pond. This allows the present invention to circulate a body of water more effectively, as the motion imparted to the water by the impeller is more efficiently passed outside of the diffuser. Thus, the centrifugal force phenomenon is utilized to create water movement at the surface which in turn operates to circulate the body of water. 
     The present invention is also equipped with freeze slots that work in conjunction with the flow diffusor of the water circulation apparatus in situations in which the flow of water from the diffusor to the body of water is interrupted or completely blocked by the formation of ice which is a common occurrence in fall and winter mornings. The slots alleviate this blockage problem and are a plurality of relatively long and narrow slots within the surface of the diffusor. These slots provide an avenue for water to pass from the interior of the diffusor to the body of water on the outside of the diffusor. Thus, when the normal flow of water has been blocked by the formation of ice, the slots allow the water inside of the diffusor to pass out to the body of water which in turn provides the desired circulation to the water despite the ice. 
     Additionally, the plurality of slots of the present invention do not interfere with the normal operation of the water circulation apparatus in normal, non-ice, weather conditions. This is true due to the fact that in normal operating conditions the water pressure inside of the diffusor is essentially the same as that outside and so the water will take the path of least resistence which is over the diffusor lip. Conversely, when there is ice blocking this normal route of passage, the rotation of the impeller creates water pressure within the diffusor which serves to force the water out of the slots and into the body of a water which effectively keeps the circulation of the body of water in progress despite the formation of ice. 
     The present invention also employs an anchoring apparatus that is made up of a pair of weighted blocks which are connected in line by means of an anchor line to either the frame of the circulation apparatus or to one of its plurality of floats. Each of the weighted blocks is most commonly made of a concrete or concrete-like material that is of the correct density that will allow the blocks to be used as an anchor at a size that is practical to handle. Additionally, the form of the concrete blocks in no way pose any threat to the integrity of the non-permeable pond liners as it contains no sharp points or edges that can puncture or tear the liner of some ponds. 
     The anchoring device for the a water circulation apparatus operates in normal weather conditions by simply sitting on the bottom of a typical pond or lagoon. In these conditions, there is no undue stress place on the line or the blocks and the most forward of the two blocks and the length of the anchor line between it and the circulation apparatus will control the position of the apparatus on the surface of the water. The problem in anchoring these types of devices is a result of less than perfect weather conditions when the wind is blowing hard and is creating waves on the surface of the water. The wave motions in these conditions operate on the circulation apparatus by constantly placing alternating tug and slack forces on the anchor. This can create a serious situation as these types of forces tend to draw the anchor across the bottom of the pond which allows the circulation apparatus to wander randomly around the surface of the pond. 
     The use of two anchor blocks in the present invention counteracts this potential problem and keeps the circulation apparatus within its desired range of motion. This occurs because as the wind speed increases and begins to move the apparatus away from the anchor, the forward anchor is pulled forward and upward on one of its edges by the anchor line. Once this has occurred, the intermediate anchor line is drawn tight and any remaining tug force is placed on the rear anchor. The weight of the front and rear anchors together along with the frictional resistance created by the rear anchor&#39;s flat position on the liner provide more than enough anchoring force to keep the circulation apparatus in the desired location. Conversely, when the tug force is released by the passage of the wave, the front anchor will return to its normal position on the liner and this action serves to absorb the slack created in the anchor line in windy weather. 
     Finally, the present invention is also equipped with a water pick up system that consists of a draft hose that is weighted towards its bottom end. This weight serves to keep the draft hose, and therefore the intake strainer head located at its terminus, on the bottom of the body of water directly below the center of the apparatus. As the anchor device for the present invention is attached through the anchor line on the outside edge of the body of the invention with the line extending outward therefrom, the anchor line can never come into contact with the centrally located draft hose. This design of the anchor and water pick up systems eliminate the possibility of encountering problems due to entanglement of the anchor line and the draft hose. 
     For a better understanding of the present invention reference should be made to the drawings and the description in which there are illustrated and described preferred embodiments of the present invention. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the present invention showing the orientation of its major components and the location of the water impeller and the water diffuser in relation to the body of the invention. 
     FIG. 2 is a top elevation view of the present invention showing the orientation of the impeller and the diffuser to the solar panels and the floats. 
     FIG. 3 is a side elevation cut-away view of the internal structure of the present invention showing the manner of construction of the impeller drive freeze sleeve and the draft tube and water flow divider. 
     FIG. 4 is a side elevation, cut-away view of the diffuser lip component of the present invention showing the manner in which it is constructed, so as to not interfere with the flow of water as it passes outside of the diffuser. 
     FIG. 5 is a side elevation view of the pivoting float component of the present invention illustrating its orientation as it fully supports the weight of the invention while it is in the water. 
     FIG. 6 is a side elevation view of the pivoting float component of the present invention illustrating its orientation when the body of the invention is out of the water and the floats are not used to support its weight. 
     FIG. 7 is a side elevation view of the impeller shaft housing body component of the present invention illustrating the manner in which it is designed that allows it to be quickly and easily removed from and installed on the frame members of the invention. 
     FIG. 8 is a side elevation view of the present invention diagraming the manner in which the water flows in a laminar fashion both from the flow diffuser on the surface of the water and to the draft tube below the surface of the water. 
     FIG. 9 is a top elevation view of the present invention diagraming the manner in which the water leaves the flow diffuser in concentric circles of laminar flowing water. 
     FIG. 10 is a side elevation view of the present invention illustrating the positioning of the flow diffuser just below the surface of the water when the invention is in use. 
     FIG. 11 is a side elevation cut-away view of a typical flow diffusor from which the flow of water has been blocked by the formation of ice. 
     FIG. 12 is a side elevation cut-away view of a flow diffusor that is equipped with freeze slots which allow for the passage of water from its interior to the body of water despite the formation of ice. 
     FIG. 13 is a top elevation view of a flow diffusor that is equipped with the present invention illustrating one possible orientation of the plurality of slots with the surface of the diffusor. 
     FIG. 14 is a side elevation cut-away view of a flow diffusor that is equipped with the present invention illustrating an individual slot&#39;s orientation in the diffusor and the manner in which it is formed in the body of the diffusor. 
     FIG. 15 is a side elevation representational view depicting the use of the present invention with a typical water circulation apparatus illustrating its orientation in normal, or non-windy, weather conditions. 
     FIG. 16 is a side elevation representational view depicting the use of the present invention with a typical water circulation apparatus illustrating its orientation in abnormal, or windy, weather conditions. 
     FIG. 17 is a side elevation view of the draft hose component of the present invention illustrating the orientation of the strainer head when on the bottom of the body of water in relation to the remainder of the draft hose. 
     FIG. 18 is a side elevation cut-away view of the strainer head portion of the draft hose illustrating the location of the strainer&#39;s internal components. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, and more specifically to FIGS. 1 and 2, the floating water circulation apparatus  10  is made up of a triangular frame member  28  which provides the structure to which the other components of the present invention are attached. The triangular frame member  28  has extending in an outwardly manner from each point of the triangle the pivoting float arms  38  which in turn provide the attachment point for the plurality floats  30 . These floats  30  are positioned at the outer edge of the triangular frame member  28  which provides a greater degree of stability for the present invention when placed in a body of water and also serves as lever arms to counteract any rotational forces applied to the present invention. The outward location of the floats  30  also serves to keep them from interfering with the flow of the circulated water. The floats  30  are pivotally attached to the lower surface of the pivoting float arms  38  and serve to hold the triangular frame member  28  of the present invention in a horizontal position above the surface of the body of water to be circulated. 
     The triangular frame member  28  provides for the mounting of the primary components of the present invention at its center. This is accomplished by having a plurality of inner support bars  29  extending inward from the triangular frame member  28  and attaching to the exterior of the impeller shaft housing body  16 . This attachment (which will be discussed in further detail below) serves to vertically suspend the impeller shaft housing body  16 , and all other components attached to it, within the central portion of the triangular frame member  28 . The result of this configuration is that the triangular frame member  28  and the floats  30  work in conjunction to hold the primary components of the present invention in the proper position relative to the body of water. 
     The primary components of the present invention are all attached to the triangular frame member  28  through the impeller shaft housing body  16 . The end of the electric drive motor  12 , which supplies the rotational force necessary to pump water, is mounted to the upper most end of the impeller shaft housing body  16 . The electric drive motor  12  is equipped with a gear reduction system that allows the electric drive motor  12  to spin at a high RPM, but reduces to a substantially lower RPM at the impeller  18 . This allows the use of a relatively low voltage electric drive motor  12  as the lower RPM of the gear reduction system provides sufficient torque at the impeller to rotate it even at slow speeds. 
     Directly below the electric drive motor  12  on the impeller shaft housing body  16  is the electronic control box  14  which is made up of a sealed box or “potted” to ensure that the electrical components contained within will operate in wet conditions and will continue to control the flow of water through the impeller  18 . The electronic control box  14  contains a linear current booster which takes the supplied voltage and amperage and varies their values to match the requirements of the electric drive motor  12 . The most common example of this is that the electronic control box  14  will convert excess voltage to amperage, which allows the electric drive motor  12  to run for a longer period of time or at a higher speed on cloudy or hazy days. 
     The power necessary to run the present invention is supplied by a plurality of solar panels  34  which are mounted along each edge of the triangular frame member  28 . The solar panels  34  are each mounted above the upper surface of the triangular frame member  28  at a slight downwardly facing angle of approximately 20 degrees which aids in keeping the face of the solar panels  34  free from debris and rain or heavy dew will have the effect of washing the surfaces clean. Additionally, the triangular orientation of the solar panels  34  ensures that the equivalent of two full panels are always producing power regardless of the present inventions position on the water with respect to the location of the sun. In one embodiment of the present invention, each of the solar panels  34  produces 55 watts of electric power and the electric drive motor  12  requires 110 watts to operate at its maximum capacity. The positioning of the solar panels  34  on the triangular frame member  28  ensures that the electric drive motor  12  will always have enough power to operate in an efficient  20  manner. It must be stated at this point that other sizes of solar panels  34  and electric motor  12  may be used to optimize the current invention for any given size pond. 
     The triangular frame member  28  of the present invention is also equipped with support legs  36  which extend downward into the body of water. These support legs are also individually attached to the outer most edge of the flow diffuser  20  which helps to secure the flow diffuser  20  in the proper orientation, within the body of the invention. Additionally, the support legs  36  also provide a means of support for the present invention in the event that the body of water is emptied or dries up or for storage purposes. 
     The impeller shaft housing body  16  extends downward from its point of attachment with the inner support bars  29  to a point just above the water impeller  18 . The water impeller  18  is located directly above the upper opening of the draft tube  22 . It is important to note that the opening of the draft tube  22  is slightly smaller in diameter than the outside diameter of the water impeller  18 . This configuration serves to create a more efficient pump as the larger diameter impeller  18  creates a partial seal over the smaller draft tube  22  opening which does not allow water to recirculate back down into the draft tube  22 . This configuration results in a more efficient pumping action. The draft tube  22  is then connected at its lower most end to the draft hose  24  which extends down into the body of water to the desired depth. The lowest end of the draft hose  24  is equipped with a debris strainer  26  which ensures that no unwanted debris will enter and clog the present invention. 
     As the impeller  18  is rotated by the electric drive motor  12  it draws up water from the bottom of the body of water through the draft hose  24  and draft tube  22 . Once the water passes through the water impeller  18  it enters the large bowl shaped flow diffuser  20  which is attached to the upper edge of the draft tube  22  and extends upward and outward therefrom. The flow diffuser captures the water as it leaves the draft tube  22  and gently directs the water, so as not to decrease overall efficiency, directly on to the surface of the water. The result of this is that an outward motion is created on the surface, which then causes induced flow, causing the entire body of water to go into motion. 
     Conversely, the rotating motion below the impeller  18  tends to diminish the efficiency of the pumping action. The present invention employs a device to counteract this effect which is illustrated in FIG.  3 . The draft tube  22  is equipped with a flow diverter vane  46  which dissects its interior into two equal parts. The flow diverter vane  46  limits the circular flow of water within the draft tube  22  and by this, increases the efficiency of the water impeller  18  as it rotates just above the flow diverter vane  46  with very little clearance between the two. This ensures that most of the energy used to generate motion in the water within the flow diffuser  20  is transferred through the water over the surface of the water being circulated. 
     The construction of the impeller shaft housing body  16  (along with other features of the present invention) is also illustrated in FIG. 3 which shows the location of the impeller drive shaft  44  within the impeller shaft housing body  16 . The water impeller  18  is connected directly to the impeller drive shaft  44 , not to the impeller shaft housing body  16 , and is suspended in a cantilever manner by the impeller drive shaft  44 . The connection of the impeller shaft housing body  16  to the triangular frame member  28  of the present invention (which is further detailed in FIG. 7) is accomplished by the use of the upper shaft attachment hook  48  and the lower shaft attachment hook  50  both of which are protrusions from the side of the body of the impeller shaft housing body  16  which have downwardly oriented slot-like openings. It is into these openings that the inner support bars  29 , which fit inside of the slot of the upper shaft attachment hook  48 , and the lower shaft attachment bars  42 , which fit into the slot of the lower shaft attachment hook  50 , slip into to hold the entire central assembly of the present invention in place. 
     On the other hand, to remove the impeller shaft housing body  16  (and therefore the impeller  18 , the electric motor  12 , and the electronic control box  14 ) one simply lifts up on the impeller shaft housing body  16  until the slots of the upper and lower shaft attachment hooks,  48  and  50 , are clear of the inner support bars  29  and the lower shaft attachment arms  42  respectively. This system of attachment for the impeller shaft housing body  16  and all of the components of the invention that are attached to it, allow for easy removal from the body of the invention for service or replacement. 
     The electronic control box  14 , which is mounted to the upper side of the impeller shaft housing body  16 , serves to contain all of the electronic controls for the present invention. In this capacity, there are a plurality of control wires that run to and from the electronic control box  14 . The first of these are the plurality of panel to control box feed lines  52  which connect the solar panels  34  to the electronic control box  14  and transmit the energy generated in the solar panels  34  to the electronic control box  14 . This energy is then processed by the electronic control box  14  and sent to the electric drive motor  12  by use of the box to motor feed wire  54 . Thus, the electric drive motor  12  uses energy created by the solar panels  34  to drive the impeller  18 , causing the body of water to be circulated. 
     The primary function of the present invention, to circulate the water contained in lakes or ponds, is best illustrated in FIG.  8 . As the impeller  18  of the invention rotates, it drives the process which circulates water throughout the body of the pond  70 , that eventually allows the water to become oxygenated naturally. This ensures that the body of water will remain in a healthy state by keeping the levels of algae in the proper ratio to the size of the pond  70 . 
     The process of oxygenating the water occurs as a result of a plurality of events occurring at the same time. The first of these is that the rotation of the impeller  18  forces water out of the flow diffuser  20  over the laminar flow diffuser lip  21  creating the surface laminar flow  66 . The surface laminar flow  66  is a very thin layer of water flowing on the surface at a very low velocity. Additionally, the surface laminar flow  66  occurs in a radial manner from the invention (an occurrence that is best illustrated in the diagram in FIG. 9) which ensures that it will eventually extend to all portions of the surface of the pond  70 . 
     While the surface laminar flow  66  is being forced out of the present invention at the surface of the pond  70 , an additional layer of water is being drawn into the draft hose  24  through the strainer  26  below the surface of the pond  70 . This layer of water, which acts in much the same manner as the surface laminar flow  66 , is called the under water laminar flow  68  and it is the water that is drawn up the draft hose  24  to be re-circulated by the impeller  18 . The under water laminar flow  68  is a very thin layer of water that is flowing at a very low velocity. Finally, as the draft hose  24  draws this layer of water equally from all portions of the pond  70 , the water is moving towards the draft hose  24  in a radial manner, which ensures that all the water in the pond  70  is involved in the circulation process. 
     The action of the surface laminar flow  66  and the under water laminar flow  68  creates an induced flow in the rest of the water contained in the pond  70 . The induced flow means that as water molecules that are contained within the surface and under water laminar flows,  66  and  68 , move away from or towards the present invention, they are replaced by other water molecules contained in the body of the pond  70 . This action causes all of the water to eventually be drawn into the circulating action driven by the impeller  18  of the invention. The result of this is that over time, all of the water in the pond  70  will reach the surface where it will come into contact with the atmosphere. Once the water contacts the atmosphere, it will absorb oxygen naturally, thus, oxygenating the entire pond  70 . 
     The water dispersion and circulation function of the present invention is also enhanced by the use of the laminar flow diffuser lip  21  which forms the outermost edge of the flow diffuser  20  and which is further detailed in FIG.  4 . The laminar flow diffuser lip  21  functions to lessen the difference between the water within the flow diffuser  20  and the water outside of it. This is accomplished by constructing a lip that is different than the body of the flow diffuser  20 . Additionally, the body of the flow diffuser  20  sits below the water line  62  when the present invention is placed in a lake or pond  70  which is illustrated in FIG.  10 . This relative position of the flow diffuser  20  in relation to the water line  62  further enhances the function of the laminar flow diffuser lip  21  as it allows waves of water moving outward from the impeller  18  to pass freely between the laminar flow diffuser lip  21  and the water line  62 . 
     Therefore, as water passes from the interior of the flow diffuser  20  to open water, the laminar flow diffuser lip  21  interacts with it as little as possible so that the motion imparted upon the water by the impeller  18  is not disrupted by the passing from the body of the diffuser  20  to the open water, which allows the present invention to operate at maximum efficiency. This function of the laminar flow diffuser lip  21  is further illustrated in FIG. 9 which clearly shows how the concentric waves  64  created by the rotation of the impeller  18  pass freely from the body of the flow diffuser  20  to the open water of the lake or pond. These features of the present invention ensure that the maximum amount of water possible is circulated by the rotation of the impeller  18 . 
     The floats  30  and float support apparatuses of the present invention are constructed in a manner that allows the floats  30  to pivot in regards to the central body of the invention and this mechanism is illustrated in FIGS. 5 and 6. The float  30  itself is pivotally attached at its most inward end (in relation to the body of the invention) to the most outward end of the pivoting float arm  38  which is in turn pivotally attached at its most inward end to the inner sections of the support legs  36  of the invention. Additionally, at the point of attachment of the floats  30  to the pivoting float arms  38 , the pivoting float arms  38  are formed into a downwardly oriented ninety degree bend. The purpose of this bend is that it allows the float  30  to pivot freely without any interference from the body of the pivoting float arm  38 . 
     The floats  30  and the pivoting float arms  38  are also equipped with a pivoting float arm support  40  which helps to keep the floats  30  in the proper position in relation to the body of the invention. The pivoting float arm supports  40  are made up of three components and span the distance between the outer portion of the support legs  36  and the most outward end of the pivoting float arm  38 . The portion of the pivoting float arms  38  that are attached to the support legs  36  are called the float arm support attachment bars  56 , they extend along a portion of the outer edge of the support legs  36  above the level that the floats  30  rest when they are in their upward position. The uppermost end of these float arm support attachment bars  56  have pivotally attached to them the upper pivoting float support bars  58  which extend outward from this point of attachment. Finally, the upper pivoting float support bars  58  have pivotally attached to them towards their outer ends the lower pivoting float support bars  60  which extend downward to the point where they are pivotally attached to the upper edge of the pivoting float arm  38 . 
     The function of the pivoting float arm support  40  is best shown in the differences between the illustrations in FIG.  5  and FIG.  6 . In FIG. 5 the floats  30  are in an upward position which most commonly occurs when the present invention is in the water and the floats  30  are supporting its entire weight. Conversely, when the invention is out of the water for storage the floats  30  drop down as illustrated in FIG.  6 . The pivoting float arm supports  40  help to guide the pivoting float arm  38  through this pivoting motion and ensure that the floats  30  remain in the correct orientation in relation to the body of the invention. 
     The manner in which a layer of ice  74  interacts with a floating water circulation apparatus  10  and how the freeze flow slots  72  of the present invention function to allow for the continued circulation of water in these circumstances are illustrated in FIGS. 11 and 12. In FIG. 11 a layer of ice  74  has formed over the diffusor  20  of the circulation apparatus  10  which has formed an ice dam  76  and has entirely closed off the interior of the diffusor  20  at the diffusor lip  21  from the open pond. This condition traps the water within the diffusor  20  which effectively renders the water circulation apparatus as ineffective as the water being drawn up through draft tube and hose,  22  and  24 , and driven by the impeller  18  cannot pass into and circulate through the pond. 
     Conversely, the diffusor  20  illustrated in FIG. 12 has been equipped with a plurality of freeze flow slots  72  which allow for a path from the interior of the diffusor  20  to the exterior. Thus, when there is an ice dam  76  formed over the diffusor  20  due to cold weather, the freeze slots  72  allow water to flow (the direction of this flow is indicated through the use of the arrows marked as number  78 ) from the diffusor  20  to the rest of the water in the pond. This direction of flow  78  is ensured because as the impeller  18  rotates in what is effectively a closed off space, pressure builds within the diffusor which forces the water out through the freeze slots  72 . Moreover, the presence of the slots  72  does not impair the effectiveness of the water circulation apparatus  10  in normal weather conditions as there is no build up of pressure within the diffusor so the water simply takes the path of the least resistence which is over the diffusor lip  21  and into the pond. 
     The orientation of the freeze flow slots  72  within the diffusor  20  and their manner of construction are further illustrated in FIGS. 13 and 14. As shown, the plurality of freeze slots  72  can be positioned radially in the body of the diffusor  20  around the centrally positioned impeller  18 . The freeze slots  72  pass entirely through the body of the diffusor  20  which allows for free water flow  78  from the interior of the diffusor  20  to its exterior. Additionally, it is important to note that this particular arrangement of the freeze slots  72  within the diffusor  20  is only one of many possible variations in size, location, and orientation all of which may work equally as well as the other and the one shown here is simply depicted for illustrative purposes. 
     The anchor for water circulation apparatus  80  is illustrated in FIGS. 15 and 16 and is made up of a pair of weighted blocks, the front anchor  82  and the rear anchor  84 , that are connected in sequence by means of an anchor line  86  and the intermediate line  88  to either the frame  28  of the circulation apparatus  10  or to one of its plurality of floats  30 . Each of the front an rear anchors,  82  and  84 , is commonly made of concrete, or of an alternate concrete-like material, and is of the correct structural density that will allow the blocks to be used as an anchor for the water circulation apparatus  10  at a size that is practical to handle. 
     Additionally, the front and rear anchor blocks,  82  and  84 , are formed in a manner so that they have no sharp points or edges. This is important to the function of the present invention in that a water circulation apparatus  10  is commonly used in a bodies of water  70 , such as lagoons and other water treatment facilities, which have-non-permeable liners  90  between the water and the earth. The purpose of these liners  90  is to ensure that any contaminates contained in the body of water  70  are not transferred to the surrounding earth or ground water. Therefore, the relatively smooth sharp of the front and rear anchors,  82  and  84 , ensures that the liner  90  will not be punctured or torn which would allow the water to enter the surrounding earth which makes a water circulation apparatus  10  that is equipped with the present invention completely safe to use in lined bodies of water  70 . 
     The dual anchor blocks operate as an anchor for use with a water circulation apparatus  10  in normal weather conditions by simply sitting on the bottom of the body of water  70  on top of the liner  90  of a typical pond or lagoon. In these conditions, there is no undue stress place on the anchor line  86  or the front anchor block  82  and the length of the anchor line  86  between it and the water circulation apparatus  10  will control the position of the circulation apparatus  10  on the surface of the water  62 . This configuration leaves the water circulation apparatus  10  to move freely about in the body of water  70  contained only by the anchor line  86  and the relative position of the front anchor  82  on the liner  90 . 
     The problem that is addressed herein comes about when the weather conditions are less than perfect and, more specifically, when the wind is blowing hard and is creating waves on the surface of the water  62 . The problem in these weather conditions is the wave motion operating on the water circulation apparatus  10  constantly places alternating tug and slack forces on the anchor  80 . This can create a serious situation as these types of forces tend to draw the anchor  80  across the bottom&#39;of the body of water  70  which can allow the water circulation apparatus  10  to wander outside of its intended confines. This is obviously an unwanted circumstance as the water circulation apparatus  10  may come into contact with the shore or other object which could result in damage to it. 
     The dual anchor  80  used with the present invention counteracts this potential problem and keeps the water circulation apparatus  10  within its desired range of motion on the surface of the body of water  70  which is being circulated. This occurs because as the wind speed increases and begins to move the circulation apparatus  10  away from the anchor  80 , the front anchor  82  is pulled forward and upward on one of its edges by the anchor line  86 . Once this has occurred, the intermediate anchor line  88  is drawn tight and any remaining tug force is then placed on the rear anchor  84 . The weight of the front and rear anchors,  82  and  84 , together along with the frictional resistance created by the rear anchor&#39;s  84  flat position on the liner  90  provide more than enough anchoring force to keep the water circulation  10  apparatus in the desired location. 
     Conversely, when the tug force on the anchor line  86  is released by the passage of the wave, the front anchor  82  will fall back to its normal position on the pond liner  90 . This action serves to absorb the slack created in the anchor line  86  as the water circulation apparatus  10  drops down the back side of the passing wave and moves back toward the position of the anchor  80 . Thus, the rocking action of the front anchor  82  works in conjunction with the frictional forces contained in the rear anchor  84  to hold a water circulation apparatus  10  in the desired location within any desired lagoon, pond, or other body of water  70 . 
     The manner of construction and the means of operation of the draft hose  24  and its related components are further illustrated in FIGS. 15,  16 ,  17 , and  18 . As previously stated, the draft hose  24  is the component of the invention through which water is drawn and channeled into the diffusor  20 . The draft hose  24  is connected to the diffusor  20  by means of the draft tube  22  which extends downward from the outside center of the diffusor  22 . The draft hose  24  extends down from the bottom terminus of the draft tube  22  to a specific orientation in relation to the bottom of the body of water  70  or the upper surface of the non-permeable pond liner  90 . 
     The draft hose  24  has attached to its lowest most end the strainer  26  which is the component of the draft hose  24  that sits just above the liner  90  and through which the pond water is initially drawn for circulation at the surface. The strainer is made up of the strainer head  94  and the strainer collar  92 . The strainer head  94  is a generally a closed off cylinder that is made of a mesh or similar material that will allow for the free flow of water through it but will keep larger items such as weeds from entering the draft hose. This filtering function of the strainer head  94  ensures that the workings of the invention will not be interfered with. Finally, the strainer collar  92  connects the strainer head  94  to the draft hose  24  and also serves as the point of attachment for the hose weight  96 . The hose weight  96  serves to keep the lower portion of the draft hose  24 , and therefore the strainer head, in the proper location in relation to the bottom of the pond. 
     The manner of construction of the draft hose  24  and its related components is important to the operation of the present invention in that their design ensures that the draft hose  24  will always hang straight down and directly below the diffusor  20 . This is accomplished through the use of the hose weight  96  which is a solid section of a relatively large diameter shaft that is mounted in the strainer collar  92 . This location of the hose weight  96  serves to hold the lower portion of the draft hose  24  on the bottom of the pond thus, acting much like a draft hose anchor. Additionally, the interior of the strainer head  94  (or that portion of the draft hose that is respectively below the hose weight  96 ) contains a hollow strainer head float  98 . The head float  98  adds a degree of buoyancy to the strainer head  94  which operates to raise the head  94  above the point where the hose weight  96  holds the draft hose  24  to the liner  90 . This is an important feature to the operation of the invention as the raised strainer head  94  ensures that water will be taken in from as close to the bottom of the pond as possible without encountering the problems of sucking in unwanted plant or waste material off the bottom. 
     The manner of construction of the draft hose  24  is also important because of the way it functions with regard to the anchoring system employed with the present invention. In windy conditions the water circulation apparatus  10  is pushed to the end of the anchor line  86  and generally held there. As the draft hose  24  normally hangs straight down below the diffusor  20  of the invention and is held in that position by the hose weight  96 , the draft hose  24  and anchoring line  86  never come into contact and there are therefore no resulting entanglement problems between the anchor line  86  and draft hose  24 . However, the rotational forces imparted to the body of the invention by the operation of the impeller  18  may lead to contact between the anchor line  86  and the draft hose  24  which in turn can result in anchor line  86  entanglement. This situation occurs during calm days and is a result of the circulation apparatuses  10  relative position to the anchor  80  and anchor line  86 . On a calm day the water circulation apparatus  10  is not held at the end of the anchor line  86  and so the line  86  is slack and the apparatus floats freely. This free floating mode allows the rotating impeller  18  of the invention to impart some of this rotational force to the body of the water circulation apparatus  10 . This causes the entire apparatus to spin slightly on the surface of the water which in turn can cause the anchor line  86  to wrap around the draft hose  24 . This, however, is not detrimental to the operation of the invention as it does not interfere with the flow of water through the draft hose  24 . Additionally, when the wind comes up enough to push the circulation apparatus  10  to the end of the anchor line  86 , the wrapped line  86  will freely uncoil and the invention will return to normal operation. 
     Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein.