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The present inventor claims the benefit of the filing dates of provisional patent applications No. 60/127,785, filed Apr. 1, 1999, and No. 60/126,811, filed Mar. 30, 1999, both of which are incorporated herein by reference. The present invention is a significant improvement on the inventor&#39;s previous patented pool cleaning systems, such as that described in U.S. Pat. No. 5,107,872, which is also incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a cleaning system for swimming pools and the like which preferably operates automatically according to a predetermnined timing sequence, and includes the possibility of employment of different types of cleaning devices. 
     BACKGROUND OF THE INVENTION 
     Historically, in the cleaning of swimming pools, suction has been used for the removal of dirt, leaves and other debris from the shell of swimming pools. Cleaning a pool manually is obviously time intensive and is generally considered a drawback to ownership of a pool. Manual cleaning involves attachment of a cleaning head to an elongated handle with wheels or the like received on the head to permit rolling along the bottom of the pool. A flexible hose is connected to the cleaning head at one end and to a skimmer at an opposite end, whereby water may be drawn through the cleaning head via the skimmer by the normal circulation system. The force of the water moving through the head creates a suction at the head which lifts trash, sediment and so forth from the bottom of the pool. Floating trash is conveyed by currents to the skimmer where it is retained in a perforated basket at the skimmer and precluded from passage to the filter system. Obviously, with such manual cleaning, and individual must move the cleaning head across the entire surface of the bottom of the pool for appropriate cleaning. 
     In an attempt to overcome the need for manual cleaning and thus make pool maintenance easier and keep the pool cleaner, various automatic cleaning systems have evolved. One such automatic cleaning system includes a cleaning device which is connectable to a source of water power which both supplies power for movement of the cleaning device and creates suction for the removal of the trash. While automatic cleaning systems of this type are generally successful in maintaining a clean pool, certain drawbacks are present. For example, water passed through the cleaning device for power must be pre-filtered to avoid the introduction of trash into the movement mechanism which could clog or otherwise render it inoperative. This type of automatic cleaning device also requires significant water pressure. In fact, water pressures in a range of 35 to 50 pounds per square inch are often necessary for proper operation. Normal filters used for cleaning pool water operate at significantly lower pressures, i.e. approximately 10 to 20 pounds per square inch. Also the normal pool filter media is retained in a housing designed for low pressure operation. Raising pressures in the normal filtration apparatus to the high levels mentioned above could therefore pose a hazard. Consequently, in order to avoid potential damage to the filter, including filter rupture, automatic cleaning systems of the type discussed above, normally go through the pool filtration system operating at lower pressure and include a jet booster pump located on the outflow side of the filter to raise the water pressures to the approximate 35 to 50 pounds per square inch range needed for the operation of the cleaning device. 
     A booster pump for this type of cleaner requires a capital expenditure for the pump. Likewise, the use of a booster pump in tandem with the normal pool pump requires additional electrical energy and, therefore, imposes an additional cost of operation. Still further, booster pumps of the type historically employed for the automatic cleaning system are merely jet pumps which receive water that has lost velocity after being forced through the filter media and they simply boost the pressure. They are short-lived, and require replacement every couple of years or so. Conversely it has been determined that in pools larger than 450 square feet of water surface area, a two pump system using two smaller horsepower pumps is actually more energy efficient and can pump more water than one larger higher horsepower pump. Moreover, when the type of pump used is identical to the pool filter pump, the life span of the pump is of longer duration than that of historically employed pressure cleaner booster pump. 
     It is therefore desirable to provide a cleaning system in which water is used to operate a cleaning device that moves along the bottom of the pool, but which does not require a booster water pump or energy in excess of that required for normal pool operation. 
     A further type of automatic cleaning that has historically been utilized for cleaning swimming pools is a total circulation system. Stationary cleaning heads are strategically located about the floor of the pool. Upon operation, water exiting from the heads dislodges trash from the surrounding pool area and moves it to a main drain in the deep end of the pool. The trash is then removed from the pool during normal water circulation to the filtration system. 
     Stationary cleaning heads include various designs. One design includes heads that are mounted flush with the bottom wall of the pool and, upon receipt of adequate water pressure, extend upwardly from the mounting location and rotate about an axis perpendicular to the local pool surface. Water thus exits from the head in a circular pattern to dislodge the trash and other contaminants as noted above. 
     A second type head mounted in a side wall of the pool in much the same fashion as a conventional water return line, but where a nozzle is provided to direct water flow in a predetermined direction for dislodging trash and contaminants and forcing them to a single area of the pool. 
     With both of the stationary type cleaning systems discussed above, there is a possibility that the bottom of the pool will not be completely cleaned. Additionally, the water force utilized to dislodge trash and contaminants from the side walls and bottom and move it to the main drain of the pool causes the contaminants to be suspended in the water. As a result, less than complete cleaning is experienced. After the cleaning cycle has run, the suspended matter will again settle to the bottom of the pool. 
     Furthermore, and perhaps most importantly, cleaning systems involving the stationary cleaning heads do not address the problem of the removal of large particles of trash such as leaves, which will not pass through a main or bottom drain in the pool. Accordingly, even with the stationary cleaning heads, a pool owner is often required to augment this cleaning system with an additional cleaning method for removal of leaves and other large contaminates. 
     Stationary cleaning systems of the rotary type discussed above, have been automated to permit certain of the cleaning heads to operate according to a pre-determined cleaning cycle. Still further a stationary system with both fixed and rotary heads has been employed that uses an in-deck canister with a large mesh strainer basket located between the pump and the main drain so that leaves and other large debris can be removed from the pool prior to reaching the pump strainer basket. This system utilizes a proprietary circulation configuration described as a “water curtain” which is designed to direct large objects to the area of the main drains. Unfortunately, this system often winds up with leaves and other large debris trapped in the main drain grate, also the mesh bag in the canister does little to alleviate obstruction of the filter with medium size debris such as sand and silt which greatly shortens filter cycles, and this system has extensive piping for cleaning return lines which are directly under the floor of the pool and thus inaccessible in the event any defects in the piping arise. Still further, the water curtain is difficult to maintain unless the filter is clean and water flows are optimal. 
     The two pump configuration used with this water curtain system pulls water through a conventional skimmer strainer basket and then sends it directly through the pump into the automatic six port hydraulic water valve and on into cleaning return lines with the strong potential for clogging and failure because of the medium sized debris such as sand and silt which passes through the skimmer strainer basket, leading to clogs either in the ports of the water valve or in the cleaning heads themselves. Additionally in large pools or pools with elaborate configurations or multiple planes of elevation, the water curtain system leaves areas that are not adequately swept with the flow currents or areas that become dead spots or trash accumulators. 
     Active main drains which may be employed in these type of systems have conventional main drain grates or raised slotted grates, which often cause mechanical failures of the aforementioned moveable cleaning units. The moveable cleaning units either become wedged in the grate of the main drain or between the grate and its housing. Furthermore larger leaves such as those from magnolias or oaks will usually not pass through these conventional grates. 
     As can be seen from the above representative or a available cleaning systems, no one system is without problems. The cleaning system of the present invention, however overcomes all of the disadvantages of the prior art systems, and is not taught or suggested thereby. 
     SUMMARY OF THE INVENTION 
     According to its preferred embodiments, the present invention is a cleaning system for a swimming pool that is characterized by plural active drains deployed about the bottom wall of a swimming pool which, when used in combination with plural stationary nozzles mounted in the side walls, receives debris swept by the wall nozzles to the active floor drains to clean the pool. Additionally, the active floor drains have a grid cover that admits larger debris and does not prohibit the use of mobile pool cleaners. The active floor drains are connected to in-deck, fine-mesh, cannister filters to remove medium and large size debris before it reaches the pump and pool filtration system. 
     An important feature of the present invention is the use of plural active floor drains in connection with sequenced side wall nozzles. By sequencing the nozzles, dirt and debris can be swept down the sides and toward nearby active floor drains where it can be sucked into cannister filters. This arrangement eliminates the need to sweep dirt and debris all the way from the bottoms of the side wall to the single drain in the deep end of the pool. It also eliminates the need for pop-up nozzles on the bottom of the pool in favor of active drains which are simpler and less expensive. 
     Another important feature of the present invention is the design of the active floor drain cover, which, by its design, curls large leaves to admit them into the drain and does not present sharp edges or obstacles to mobile cleaning systems. The present invention not only brings the main drains to the dirt but can be designed to locate main drains in planes of the pool that would ordinarily be dead spots. Additionally, not only can the flows from the cleaning return lines be sequenced or constant, so too can the flows from the active main drains also be sequenced or constant where desirable. 
     Obviously, the present invention also retains the feature of the inventor&#39;s past inventions whereby a mobile pressure driven or suction driven robot or robots can be added to the cleaning cycle to bring about complete cleaning coverage of all areas of the pool regardless of configuration or multiple elevation planes. 
     Still another feature of the present invention is the use of two or more sets of side wall nozzles, one just below the water line and one near the cove so that, when properly sequenced, dirt and debris can be moved down the wall and across part of the bottom wall to the active drains deployed there. This feature enables a complete sweep of the wall and part of the floor but without undue turbulence that would otherwise resuspend finer particulates. 
     Other features and their advantages will be apparent to those skilled in the art of pool cleaning technology from a careful reading of the Detailed Description of Preferred Embodiments, accompanied by the following drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings, 
     FIG. 1 is a perspective view of a typical swimming pool employing a cleaning system according to teachings of the present invention; 
     FIG. 2 is a top plan view of the pool as illustrated in FIG. 1; 
     FIG. 3 is a cross-sectional view taken along a line  3 — 3  of FIG. 2; 
     FIG. 4 a  is a perspective, partially cut-away view of a floor mounted stationary cleaning head for use with a cleaning system according to a preferred embodiment of the present invention; 
     FIG. 4 b  is a perspective view of a wall mounted stationary cleaning head for use with a cleaning system according to a preferred embodiment of the present invention; 
     FIG. 5 a  is a top view of a floor mounted active drain, according to a preferred embodiment of the present invention; 
     FIG. 5 b  is a cross sectional view of a floor mounted active drain, according to a preferred embodiment of the present invention; 
     FIG. 6 is a cross sectional view of a cannister filter for use with an active floor drain, according to a preferred embodiment of the present invention; 
     FIG. 7 a  is a schematic illustration of the plumbing connections, according to a preferred embodiment of the present invention; 
     FIG. 7 b  is a schematic illustration of the plumbing connections, according to an alternative preferred embodiment of the present invention; and 
     FIGS. 8 a,    8   b,    8   c,    8   d,  and  8   e  are schematic plumbing diagram of further embodiments according to teachings of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Making reference to FIGS. 1-3; preferred embodiments of the present invention will now be described in detail. A swimming pool generally indicated as  10  is illustrated in FIGS. 1-3 having side walls  12  and a bottom wall  14  with the depth of the pool  10  varying along the length of same, as indicated for example, in FIG.  3 . Also as indicated, a plurality of steps  20  are illustrated at one end of pool  10  for easy access to the shallow end of the pool. Likewise, at an opposite end of pool  10  a seat  22  is provided which extends downwardly along side wall  12  for a predetermined distance and provides a location where a swimmer may sit, rest or otherwise use same as a step for climbing out of the deep end of the pool. Obviously, other areas for spas or the like may likewise be provided. 
     Typically, such a pool installation is a gunite type pool, constructed of vertical and horizontal reinforcing bars (not shown} which line the pool shell and onto which a cementitious composition (gunite) is sprayed. With the shell excavated and prior to application of the gunite composition, plumbing lines are installed which become encapsulated by the gunite in either side walls  12  or bottom  14 . For example, as illustrated, a main drain  30  is shown in bottom  14  of pool  10  with an appropriate main drain suction line  32  connected thereto and extending outwardly therefrom. An opposite end of suction line  32  would be appropriately connected to a circulating pump  40  that pulls water from the pool and through a connector line  42  feeds same to an appropriate filter system  44 . Conventional water return line  50  extends from a discharge side of filter system  44  and returns water through one or more appropriate return lines  52  (see FIGS. 7 a  and  7   b ) to pool  10 . 
     Additionally, one or more skimmers  60  are conventionally mounted in side wall  12  of pool  10  with an appropriate suction line  62  likewise connecting skimmers  60  to pump  40 . Skimmers  60  are intended to remove water from the surface of the pool in order to collect leaves or other debris floating thereon. Generally, a conventional skimmer suction line  62  and main drain line  32  are brought together on the suction side of pump  40  into a common pump feed line  64  with appropriate valving to control whether water is removed from the bottom of the pool, the surface of the pool or both. 
     During normal operation therefore, water from pool  10  is pulled by pump  40  through main drain suction line  32  and skimmer line  62 , and is then pumped to filter system  44  where the water is filtered to remove contaminants and is then returned via return lines  50 ,  52  to the pool. Filter system  44  conventionally is a metal or polymer structure that contains sand or diatomaceous earth filter media and operates in a general range of from about 10 to 20 pounds per square inch of pressure. Any other type filter system could, however, be employed. 
     Referring to FIGS. 1 and 2, in a large pool or a pool with a configuration that otherwise defeats conventional circulation patterns, additional strategically placed active main drains  30  are placed so that, with appropriate valving or timed control of pump  40  and perhaps with an auxiliary pump  70  and the use of automatic valves banks of cleaning heads, could be activated in sequence to effectuate cleaning in several zones of the pool, thus alleviating the necessity for driving all dirt and debris to the deepest portion if the pool as is commonly done with other cleaning systems. 
     According to the present invention, stationary cleaning heads generally indicated as  72  (see FIG. 3) may be flush mounted on the planar surfaces of steps  20  and seat  22 . As illustrated in FIGS. 1,  2  and  3 , plural banks of stationary cleaning heads  72  are connected via individual cleaning return lines  76  to a common cleaning return line  78  such that water passing into common cleaning return line  78  will operate all stationary cleaning units  72  in communication therewith. 
     As can be seen in FIG. 4 a,  stationary cleaning unit  72  includes a housing  80  positioned within the gunite  82  of the appropriate surface and with a top of housing  80  being flush with an upper surface thereof. Located within housing  80  is a hollow body  84  having one or more tangential openings  86  therein. Upon receipt of water through return line  76 , body  84  will be forced upwardly by the force of the water until a flange  88  engages a portion  90  of housing  80 . Water exiting tangential openings  86  will impart a rotary motion to body  84 . A circular water pattern is thus created about head  72  immediately adjacent the surface thereabout which will dislodge and force away any debris or sediment thereon thus cleaning the surface. With an appropriate number of heads  72 , a set of steps  20 , a seat  22  or the like may thus be cleaned. 
     In order to clean side walls  12 , near the water line and lower, at the cove or the curved juncture between side wall  12  and bottom wall  14 , directional cleaning nozzles  74  are mounted in side wall  12 . As illustrated in FIG. 4 b,  directional nozzles  74  include a removable fitting  92  that is threadably secured to a coupling at an end of return line  76 , having a central opening  94  with a global shaped element  96  residing there within. Global element  96  includes a slot  98  through which water may be directed. The direction of water flow through directional nozzle  74  is thus determined by the position of slot  98  relative to side wall  12 . In like fashion, as with stationary mounted cleaning heads  72 , a plurality of directional nozzles  74  may be interconnected to form a bank of same via individual return lines  76  and common cleaning return line  78 . Directional nozzles  74  can thus be employed to direct water across the surface of walls  12  to dislodge and remove loose algae, sediment or other debris therefrom. For some applications directional nozzles  74  are preferably made to sweep cyclicly through an arc of side wall  12  to direct water at pressure over the whole arc. 
     Banks of directional nozzles  74  are operated in sequence (best seen in FIG. 3) with an upper bank operating first to dislodge dirt and debris from just below the water line and sweep it downwardly toward the cove where a second, lower bank of nozzles  74  receives the dislodged dirt and, upon being activated, dislodges dirt and debris in the vicinity of the cove and sweeps it, together with the dirt and debris from above, toward the nearest active drain  30 , or alternatively a bank can be comprised of a combination of upper and lower nozzles wherein the nozzles are activated simultaneously and as the flow from the upper nozzle begins to lose its velocity, the flow from the lower nozzle augments the flow over the cover towards the nearest active main drain. 
     Active drain  30  has a grate  110 , illustrated in FIG. 5 a  and  5   b,  configured to curl leaves and other larger debris so that it enters drain  30  and does not have to be removed by hand or using other cleaning methods. Main drain grate  110  and an associated main drain pot  112  are shown having tubular vanes  114  staggered so that on a horizontal plane the leading edge of each vane  114  and the dome  116  of grate  110  present a rounded edge to any and all objects that are forced into contact with it. Thus the finned disc of a suction cleaner or the whip tail of a pressure cleaner, for example, would be deflected upward and away from the main drain grate whereas, conversely, leaves and other debris since they are not moving under their own power would be drawn into one of the orifices by the underlying suction from the pump  40  and the rounded edges of vanes  114  and dome  116  would help a leaf or other large waterlogged debris to conform itself so that it would be drawn through the orifice between the vanes  114  and dome  116  of grate  110 . 
     Grate  110  would connect to pot  112  which as can be seen has a rounded raised edge  118  designed to protrude above pool floor  14  so that the aforemention staggering created by vanes  114  and dome  116  of grate  110  is furthered. Insert tabs  120  on grate  110  would seat in insert slots  122  thus locking main drain grate  110  into main drain pot  112 . Obviously screws or other fastening methods could be used to further secure this connection. 
     Referring to FIG. 6, an improved form of in-deck canister  128  is shown with a wider upper housing  130  which connects to a deep narrower vertical lower housing  132  containing a large fine mesh bag  134  which is kept from collapsing by form ring  136  and weight ring  138 . Mesh bag  134  is woven over form ring  136  which rests on mesh bag retention collar  140 . A removal chain  142  is connected to form ring  136 . A positive seal lid  144  locks has an “O” ring slot  146  and an “O” ring  148  which is seated in slot  146  just inside the lower outer edge of positive seal lid  144  when positive seal lid  144  is locked in place. An equalizer line  150  through sidewall  12  allows water “A” from pool  10  to flood over positive seal lid  144  in case a defect exists or develops either in lid  144  or “O” ring  148  thus protecting the pump connected to canister out-flow  152  from losing prime. In-flow connection  154  could be connected to active main drain  30 , or, alternatively, to a mobile cleaner. A deck lid  156  fits snugly into the top of upper housing  130  and acts as a safety cover. 
     Under standard pool operating conditions as have been described herein above, pump  40  draws water from pool  10  via main drain  30  and/or skimmer  60  through the respective suction lines  32  and  62 . Water then exits the discharge side of pump  40  and is forced through filter system  44 . Within filter system  44 , the water is cleaned by filter media therein and is then returned to pool  10  via normal return lines  50 ,  52 . 
     In preferred embodiment illustrated schematically in FIG. 7 a,  a control means  200  automatically closes a valve  202  and opens valve  204  which causes water to be pulled from pool  10  through a filter  206  such as cannister  128  directly connected to an active main drain  30  or a skimmer  60  with an auxiliary filter  210 . The water then exits filter  206  and passes via-suction line  212  to pump  40 . Control means  200  also has automatically adjusted valve  214 , which preferably is an automatic three-port valve, to close the valve port leading to filter system  44  and open the valve port in communication with cleaning return line  216 . The water is then directed to hydraulic valve  218  preferably a HYDRA +61 valve where the water is distributed in a predetermined sequence by the opening and closing of individual valve ports of valve  218  to cleaning return lines  76  and  78  to stationary cleaning heads  72  and directional nozzles  74 , respectively and potentially to a mobile device  130  through its return line  132 . Control means  200  then could close valve  204 , open valve  202  to pull water from main drain  3  and skimmer  60  through suction lines  32  and  62  and through pump  40 . Control means  200  would then adjust valve  214  to divert flow through filter  44  into return line  50  to returns  220 ,  222 ,  224  in one set and  220 ′,  222 ′, and  224 ′ in another set. Returns  220 ,  222  and  224  are set high and returns  220 ′,  222 ′, and  224 ′ are set low in pool wall  12  and arranged circumferentially around pool to enhance the Coriolis effect during the filtration and circulation cycle. Obviously valve  214  could be adjusted to allow both the cleaning and filtration cycles to occur simultaneously albeit in a diminished capacity. 
     Referring now to FIG. 7 b  in another preferred embodiment, control means  200  activates pump  40  which draws water through either main drain  30  or skimmer  60  or both depending on the setting of three-port valve  202  as before. Control means  200  at a predetermined time activates a second pump  40 ′ which draws water through active drains  30 ′, then through skimmer  60  and prefilter  206  or through pre-filter canister  128  via conduit  62 ′. Pump  40 ′ then forces the pre-filtered water into automatic hydraulic six-port valve  218  and then through cleaning return lines  76 ,  78 , and  132 , as before, thus accomplishing a cleaning cycle. 
     In a preferred embodiment, the various noted valves alluded to above are automatic, with actuation of each of the valves being controlled by control means  200 . Obviously, however if desirable, certain of the valves may be manual instead of automatic or include a manual override feature such that an individual may manually operate same in the event of malfunction of control means  200 , or if needed to clean the pool outside of a normal cleaning cycle. While control means  200  has been illustrated schematically, such means may be any of a number of automatic systems for opening and closing the various valves according to the particular operational cycle desired, or the conventional valves can be preset manually and activated by a time clock which initiates the action of a pump that causes flow to be diverted through these preset valves to initiate a cleaning cycle. For example, electronically operated valves or hydraulic valves may be employed in conjunction with timing clocks. For example, a “JVA 2400 JANDY” valve actuator produced by Jandy Industries, a subsidiary of Savoy Corporation, San Rafael, Calif., may be employed for operation of individual three-port valves. Additionally, a “hydra 6+one” water valve produced by Parmount Leisure Industries, Scottsdale, Ariz., in conjunction with timing clocks associated with pump  40 ′, may likewise be employed which includes a plurality of valve ports located in a single housing with individual water lines leading to the various ports within the housing and with a timing mechanism incorporated therein for opening and/or closing the individual valve ports in a predetermined sequence. Thus, in this case, the pump acts as the valve means associated with control means  200  to activate the hydraulic valve. 
     Referring to FIG. 8 a,  an embodiment of the present invention is illustrated wherein in the normal circulation system, two skimmers  240 ,  240 ′, have a cartridge filter or fine mesh pre-filter  242 ,  242 ′, respectively incorporated therewith, such as might be utilized with a vinyl pool. In addition to skim filters  242 ,  242 ′, a drain  230  is illustrated which could be representative of a main drain in the bottom of the pool which is connected to filters  242 ,  242 ′. Skimmers  240 ,  240 ′ and drain  230  are thus connected to a pump  252  via circulation lines  244 ,  244 ′ respectively, which join at line  251  to feed into pump  252 . Appropriate valves  246 ,  246 ′ are located in lines  244 ,  244 ′, respectively, to control water flow from skimmers  240 ,  240 ′. In this embodiment, of course, all of the filtration occurs at cartridge filters  242 ,  242 ′ and same maybe located adjacent pump  252  instead of at skimmers  240 ,  240 ′ or likewise on the discharge side of pump  252 . Return lines leading from pumps  252  and connected to valve  293  are conventional return lines  256  or cleaning return lines  245 ,  274 ,  284 ,  284 ′ as discussed hereinbelow. 
     The cartridge filters as discussed herein may by way of example be HYDRO-PAK cartridge skim filters, produced by Baker Hydro Filtrations Inc., Augusta, Ga., which include apolyester fabric cartridge located in a housing for same below the skimmer. When dirty, the fabric cartridge which generally includes 50 square feet of surface area, may be removed, cleaned with a garden hose and returned. If located on the pressure side of a pump, then of course the filter must be able to withstand the higher pressures. Alternatively, the filters on the suction side may be fine mesh pre-filters such as the pre-filter skimmer manufactured by Baker Hydro Filtrations Inc., Augusta, Ga., with fine mesh of 0.050 inch or smaller, or, for example, pre-filter mesh bags placed inside a conventional skimmer basket, the FIRST FILTER manufactured by Keith Brothers Inc. of Ponte Vedre Fla. 
     Cleaning return line  245  is connected to a mobile cleaning unit  260  while the return lines  274 ,  284 ,  284 ′ are connected to stationary cleaning heads  272 ,  280 ′,  280 , respectively. According to this embodiment, two banks of wall mounted cleaning heads  280 ,  280 ′ (three heads per bank) are included each on its separate return line  284 ,  284 ′. Once again, rather than the discharge powered mobile cleaning unit  260  of this embodiment, it is to be understood that a suction powered cleaning unit may be hooked into the suction side of the present circulation system either through one of the skimmers  240  or  240 ′ or through a specified inlet (not shown) with an independent strainer associated therewith. 
     During a cleaning cycle of the embodiment of FIG. 8 a,  control means  200  would close valve  246  (or  246 ′) if one of the skim filters is to be inoperative, and adjust valve  293  to close same in favor of manual return line  256  and open to the cleaning return lines  245 ,  274 ,  284 , and  284 ′. Control means  200  would then sequentially open one or more of the valves  247 ,  281 ,  281  ′ and/or  271  according to the desired cleaning cycle. In fact, with a plurality of banks of wall mounted cleaning heads  280 ,  280 ′, about a pool, banks could be sequentially opened starting from the shallow end of the pool to wash all the pool debris to the deep end for removal through the main drain or to multiple main drains which could be located in proximity to each bank. Obviously control means  200  could open valve  246  and could activate pump  293 ′ which in this case serves the purpose of valve  293  in FIG. 8 a  with pump  293 ′ acting as a motorized valve, and pump  293 ′ would serve as an additional valve opening flow to a hydra valve that would take the place of valves  247 ,  281 ,  281 ′ and  271 , thus pump  293 ′ may serve as the control means for a valve means. 
     During a cleaning cycle, in the embodiment in FIG. 8B, control means  200  would open valve  246  to direct flow through line  251 ′ and simultaneously activate pump  252 ′ which is serving the same role as valve  293  in FIG. 8 a  and when activated would direct flow to valves  247 ,  281 ,  281 ′ and  271  to initiate a cleaning cycle. When control means  200  deactivates pump  252 ′ and closes valve  246  to line  251 ′, the pool would revert to a normal circulation cycle. Although not shown, control means  200  could control pump  252  and valve  246 ′ to allow simultaneous cleaning cycle and circulation cycle or just cleaning or just circulation. 
     With the embodiment in FIG. 8 c  control means  200  would adjust valve  293  to close flow to line  256  ending the normal circulation cycle and initiating a cleaning cycle by directing flow through line  256 ′ to hydraulic valve  247 ′ which in turn would direct flow by opening and closing individual valve ports in a timed sequence to direct flow in a predetermined sequence to cleaning lines  245 ,  284 ,  284 ′ and  274 . Obviously valve  293  would not be necessary if one or more of the ports in hydraulic valve  247 ′ were dedicated to the normal circulation line  256  in which case pump  252  would serve as the control means for valve  247 ′ and both normal circulation and cleaning cycles could occur sequentially and at predetermined intervals. 
     In the preferred embodiment in FIG. 8 d  which would be employed in larger pools or pools with greater hydraulic flow requirements, control means  200  would close valve  246  to line  251  and open it to line  251 ′ and simultaneously activate pump  252 ′ which in turn would activate hydraulic valve  247 ′, thus initiating a cleaning cycle, as the individual valve ports in valve  247 ′ open and close in a predetermined sequence. 
     Obviously, if pump  252  is not deactivated by control means  200  when it activates pump  252 ′, it would be possible for a normal circulation cycle to be under way simultaneously with a cleaning cycle. Obviously as well in this configuration, it would also be possible to have further multiple cleaning banks or circulation banks or a combination of both controlled by the hydraulic multiport valve. 
     Although not shown, it is readily understood that skim filter  240 ′ and  242 ′ could be standard skimmers located on the suction side of pump  252  and a conventional filter  254  could be on the discharge side of pump  252  in line  256  and the water could be filtered on the pressure side of pump  252  before reentering line  256  to return to the pool through normal circulation cycle ports or cleaning head ports. 
     In another preferred embodiment (FIG. 8 e ) which could be employed in large pools or pools with multiple planes or complex configurations, control means  200  would sequentially open valve  248  to active main drain  230  while simultaneously activating pump  252  which would in turn activate hydraulic valve  247  via initiating flow through return line  256 ′. Flow through cleaning return lines  245  and  285  could be sequenced to correspond with the opening of main drain  230  and these banks would be located to direct flow towards main drain  230 . Control  200  would then close flow from main drain  230  and open flow from main drain  230 ′ to correspond with the sequencing of flow in hydraulic valve  247  from banks  245  and  285  to banks  286  and  274 ′ with the banks being located to direct flow towards main drain  230 ′. Similarly, control means  200  could either simultaneously or in a predetermined sequence activate valve  248 ′ to open flow from main drain  231  and close flow from  231 ′ while simultaneously activating pump  252 ′ which in turn would activate hydraulic valve  247 ′ via initiating flow through return line  257 . Hydraulic valve  247  could be sequenced to direct flow to cleaning return lines  245 ,  282 , which would direct flow to main drain  231  and the opening of flow from main drain  231 ′ would then correspond with the closing of banks  245  and  282  by hydraulic valve  247 ′ and the opening of flow through cleaning return banks  284 ′ and  274  which in turn would direct the flow towards main drain  231 ′. 
     Obviously, this sequencing could be done using electronic valves or for example in the case of larger commercial pools, could be done manually with manual valves. Obviously, another variant of this preferred embodiment would be sequencing flow from main drains in multiple areas of the pool while merely allowing hydraulic valves to sequence in their normal pattern thus allowing a randomization of which active main drains were operative in relation to directed flows by cleaning heads. This would have the effect of collecting sediment that might have been forced past one set of main drains that flow was initially towards and ultimately trapping the sediment in another more distant set of drains. 
     While various embodiments of the present invention have been described hereinabove, it should be pointed out that individual features of any of the embodiments may be incorporated with other individual features of other embodiments to provide a particular cleaning system. Moreover, in any embodiment illustrated having the control means incorporated therewith, obviously such system could be a manual system. Likewise, any system shown without a control means could have an automatic control means included therewith to totally automate the system. 
     Additionally the pump or pumps utilized in standard swimming pool configurations may serve both as a pump and a valve as it is well understood that a swimming pool pump is merely a motorized centrifugal valve and the definition of a valve as defined by the American National Standards Institute is “any device in a pipe that can partially or totally obstruct the flow of water or permit flow in on direction only.” 
     It will be understood, of course, that while the forms of the invention herein shown and described constitute preferred embodiments of the invention, it is not intended to illustrate all possible forms of the invention. It will also be understood that the words used are words of description rather than of limitation and that various changes may be made without departing from the spirit and scope of the invention herein disclosed.

Summary:
A cleaning system for a swimming pool having plural active drains deployed about the bottom wall of a swimming pool and that cooperate with plural stationary nozzles mounted in the side walls that direct a flow of water down the side wall of the swimming pool. The directional nozzles dislodge debris from the side and bottom walls which is swept toward and received by the plural active floor drains, thus cleaning the pool. Additionally, the active floor drains have a grid cover that admits larger debris and does not prohibit the use of mobile pool cleaners. The active floor drains are connected to in-deck, fine mesh cannister filters to remove medium and large size debris before it reaches the water pump and balance of the pool filtration system.