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CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation-in-part of PCT/IB2008/053718 filed Sep. 15, 2008, the entirety of which is hereby incorporated by reference. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    This invention was not federally sponsored. 
       BACKGROUND OF THE INVENTION 
     Field of the invention 
       [0003]    This invention relates to the general field of pool cleaners, and more specifically toward a suction type turbine-driven pool-cleaners utilizing vortex turbines to propel and steer the pool cleaner. 
         [0004]    Suction type turbine-driven pool-cleaners exists in various guises, some utilize footpads to propel them forward while others use wheels and/or tracks. Each of these cleaners have various benefits, however, they have in common a turbine that has to, at least to some extent, have at any specific interval one or more blades, or part thereof between the inlet and outlet flow channel. In other words, the turbine is in the direct path of the flow of water. 
         [0005]    This creates potential blockage problems as debris travels via the path of obstruction created by placement of the turbine between the in and outlet. Furthermore the flow of water is restricted by the turbine blades. Designers have tried to overcome this problem to some extent by using fewer blades on the turbine. 
         [0006]    A Common phenomenon with turbines is that the blade creates drag as it rotates in the water column. Curvature of the blades will only improve this aspect to a certain extent. It speaks for itself that all other factors being equal the less the drag on the turbine blades the more power can be extracted from the turbine unit. Typically a happy medium exists between the width and shape of the blades. Usually the turbine blades will be as wide as or wider than the orifice in the inlet flow channel. 
         [0007]    The aim of this invention is to create an efficient turbine that creates very little drag and an unobstructed open path for debris passing through the inlet and outlet flow channel. 
       SUMMARY OF THE INVENTION 
       [0008]    For this invention a vortex chamber of specific design allows a vortex to be formed by the flow of water from in to outlet. By positioning a comparatively small and narrow turbine in the already formed vortex, distanced well away from the direct path between inlet and outlet channels, an increase in comparative power is generated compared to the usual placement of the turbine or part thereof in-between the inlet and outlet flow channel where the flow exerts direct pressure on the turbine blades for rotation. 
         [0009]    Blade drag is minimized as the water column rotates irrespective of whether a turbine is positioned in the rotating water column or not. The major benefit of the positioning of the turbine away from the direct path between inlet and outlet is the creation of an open channel insofar as water-flow or debris consumption is concerned. 
         [0010]    This feature also creates the opportunity for inlet and outlet paths to be located in very close proximity to each other as no allowance has to be made for the placement of a turbine in-between the channels. Due to the efficiency of the vortex design, the turbine blades do not have to be cupped or curved like existing designs to achieve sufficient power for the intended purpose of the drive unit. Another benefit is that the rotating water column allows large debris to be rotated in a similar fashion within the chamber thereby positioning it to conform to the outlet channel. The design incorporates a very simple reversing mechanism by merely diverting the intake of flow to rotate the vortex in the opposite direction. Due to the blades not being cupped or curved to minimize drag, no power loss occurs. The benefit of this is that the drive gears remain in their respective engaged position. 
         [0011]    In other cleaners complex gear-shift change and clutch mechanisms are used to reverse direction of the cleaner, typically these are prone to high wear and tear. Compared to other complex steering mechanisms another feature of this invention is the use of a simple differential unit positioned in the drive shaft between the left and right drive wheels or tracks for steering purposes. Application of a braking force to one set of wheels or tracks on either side of the differential will steer the cleaner in any direction pre-determined by a cam design. The steering design may also be programmed to turn the cleaner around when the cleaner reverses direction. 
         [0012]    Due to the efficiency of the design, sufficient power is generated to include an optional fan unit similar to that disclosed in U.S. Pat. No. 4,168,557 to assist with down-force in slippery conditions such as tiled pool surfaces. 
         [0013]    In a preferred embodiment, instead of using a differential, twin turbines may be inserted in the vortex chamber each providing drive to a different set of wheels or tracks. By merely applying braking force to one of the turbine output shafts, a similar steering effect is achieved. It can be seen, therefore, that the placement of turbines in the already formed vortex has the main advantage of creating an open channel for flow and debris while at the same time providing sufficient power to operate, even high resistance track drive units and accessory items at normal flow rates. This same design can also be modified for use in pressure type cleaners. 
         [0014]    The flow can be equally diverted between the two chambers to provide input to each side of the drive train individually. This enables each side of the drive train to be slowed down, stopped, or reversed together or individually. In between the dual chambers, an inlet outlet plenum zone will distribute flow to the dual chambers while allowing debris to continue unhindered from the inlet to the outlet. 
         [0015]    By controlling the flow into the chambers, the vortex and thus turbines can be interrupted in one or both chambers to slow, stop, or reverse the turbine within that chamber. Depending upon which chamber or chambers have been stopped, reversed, or slowed down, the cleaner can go forward, backwards, steer left, or steer right. Although this design lends itself to steer by applying a braking force to one turbine&#39;s drive train or the other without a differential, flow interruption is the preferred embodiment due to its simplicity of the implementation. 
         [0016]    The actuating mechanism for steering and reversing the cleaner can be programmed to intermittently steer or reverse the cleaner. This can be achieved by a cam design, a timed electrical, or by other means known in the art. Additionally, a flotation device integrated into the steering flap enables the clean to steer in a predetermined direction when the cleaner transitions from a horizontal to a vertical position. 
         [0017]    The design of the current invention lends itself to be significantly wider than current cleaners of this type, thereby enabling the current invention to clean a wider area at one time. The wheel base is kept short such that the clean can transition easily between horizontal and vertical positions. Further, the intake zone area underneath the clean can be shaped such that the cleaner will not get stuck on the bottom drain of the pool. 
         [0018]    Accordingly, the current invention is a cleaner comprising a housing for one or more vortex-turbine mechanisms, tracks for movement over submerged surfaces, a differential mechanism for steering purposes, a reverse of inlet flow mechanism, a cam design for engagement of steering and reversing mechanisms, a means of controller inlet flow for steering purposes, and a means of controlling flow for reversing direction of cleaner movement. 
         [0019]    There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. The features listed herein and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0020]    The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of this invention. 
           [0021]      FIG. 1  illustrates a side cutaway drawing of the turbine within the vortex chamber. 
           [0022]      FIG. 2  illustrates a perspective cutaway drawing of the turbine within the vortex chamber. 
           [0023]      FIG. 3  illustrates a top view of the cleaner with outer body removed to show the relationship between the various parts. 
           [0024]      FIG. 4  illustrates the steering mechanism and the cam position in a first steering position. 
           [0025]      FIG. 5  illustrates a close up view of the steering mechanism and the cam position of  FIG. 4 . 
           [0026]      FIG. 6  illustrates the steering mechanism and the cam position in a second steering position. 
           [0027]      FIG. 7  illustrates a close up view of the steering mechanism and the cam position of  FIG. 6 . 
           [0028]      FIG. 8  illustrates the steering mechanism and the cam position in a third steering position 
           [0029]      FIG. 9  illustrates a close up view of the steering mechanism and the cam position of  FIG. 8 . 
           [0030]      FIG. 10  illustrates a side view of the cam design for steering purposes as well as the directional flippers incorporated within the cam for reversing mechanism. 
           [0031]      FIG. 11  illustrates a perspective view of  FIG. 10 . 
           [0032]      FIG. 12  is a perspective view of the engagement of the reverse mechanism and the mechanisms incorporated therein in a first position. 
           [0033]      FIG. 13  is a side view of  FIG. 12 . 
           [0034]      FIG. 14  is a perspective view of the engagement of the reverse mechanism and the mechanisms incorporated therein in a second position. 
           [0035]      FIG. 15  is a side view of  FIG. 14 . 
           [0036]      FIG. 16  is a perspective view of the engagement of the reverse mechanism and the mechanisms incorporated therein in a third position. 
           [0037]      FIG. 17  is a side view of  FIG. 16 . 
           [0038]      FIG. 18  is a side view showing the forward direction engagement and the inner cam mechanisms incorporated therein in a first position. 
           [0039]      FIG. 19  is a close-up side view of the cam mechanism shown in  FIG. 18 . 
           [0040]      FIG. 20  is a close-up perspective view of the cam mechanism shown in  FIG. 18 . 
           [0041]      FIG. 21  is a side view showing the forward direction engagement and the inner cam mechanisms incorporated therein in a second position. 
           [0042]      FIG. 22  is a close-up side view of the cam mechanism shown in  FIG. 21 . 
           [0043]      FIG. 23  is a close-up perspective view of the cam mechanism shown in  FIG. 21 . 
           [0044]      FIG. 24  is a side view showing the forward direction engagement and the inner cam mechanisms incorporated therein in a first position. 
           [0045]      FIG. 25  is a close-up side view of the cam mechanism shown in  FIG. 24 . 
           [0046]      FIG. 26  is a close-up perspective view of the cam mechanism shown in  FIG. 24 . 
           [0047]      FIG. 27  is a front view of a dual vortex twin turbine unit. 
           [0048]      FIG. 28  is a perspective view of the dual vortex twin turbine unit shown in  FIG. 27 . 
           [0049]      FIG. 29  illustrates a top perspective view of the cleaner in a dual chamber, twin turbine configuration with the outer body removed to show the relation ship between the various parts. 
           [0050]      FIG. 30  is a close-up perspective view of the inlet-outlet area of the cleaner shown in  FIG. 29 . 
           [0051]      FIG. 31  illustrates a top perspective cutaway view of the cleaner of  FIG. 29 , with steering and reverse flaps in a closed position. 
           [0052]      FIG. 32  is a side view of the inlet-outlet area shown in  FIG. 31 . 
           [0053]      FIG. 33  is a close-up perspective view of the reverse flap area in  FIG. 31 . 
           [0054]      FIG. 34  illustrates a top perspective cutaway view of the cleaner of  FIG. 29 , with the steering flap in the open position. 
           [0055]      FIG. 35  is a close-up perspective view of the reverse and steering flap area in  FIG. 34 . 
           [0056]      FIG. 36  is a close-up perspective view of the inlet-outlet area in  FIG. 39 . 
           [0057]      FIG. 37  is a side view of the inlet-outlet area in  FIG. 39 . 
           [0058]      FIG. 38  is a close-up perspective view of the reverse flap area in  FIG. 39 . 
           [0059]      FIG. 39  illustrates a top perspective cutaway view of the cleaner of  FIG. 29 , with the steering flap in the closed position and the reverse flap in the open position. 
           [0060]      FIG. 40  is a bottom perspective view of the cleaner of  FIG. 29 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0061]    Many aspects of the invention can be better understood with the references made to the drawings below. The components in the drawings are not necessarily drawn to scale. Instead, emphasis is placed upon clearly illustrating the components of the present invention. Moreover, like reference numerals designate corresponding parts through the several views in the drawings. 
         [0062]    As can be seen in  FIGS. 1 and 2 , the inlet  1  and outlet  2  are in very close proximity to each other, with turbine  3  well away from the debris path flow, represented by line  4 . The debris and flow path is shown with flow direction line and arrows. 
         [0063]    In this configuration the angle of flow is controlled by a variable flap  5  to allow for reverse rotation of the turbine system, but it can also be fixed should other means of reverse engagement be utilized. 
         [0064]    When suction is applied to the outlet  2 , flow will enter from the inlet  1  in the direction of the arrows, and a vortex will form in the vortex chamber  12  allowing the turbine  3  to rotate in the same direction as the vortex; flow as well as debris will continue unhindered through the outlet  2  as shown by the line  4 . Due to the turbine  3  being positioned well away from the direct flow path between  1  and  2 , debris and flow will not be influenced by the turbine as in other turbine cleaners. This makes the design very effective insofar as debris consumption is concerned. 
         [0065]      FIG. 3  illustrates the cleaner as a whole with outer housing removed to show in particular the differential unit  6  and cam  7  reverse and steering mechanisms as well as their relation to the rest of the cleaner, including tracks  8 , drive wheels  9 , drive axles  10  and  11 , vortex chamber  12 , intake at flap  5 , and outlet  2 . 
         [0066]    Once drive is being transferred from the turbine to the gearing system  13  and differential unit  6 , the cleaner will move forwards or backwards depending on the position of the variable steering flap  5 . The differential unit  6  is placed in-between the two output drive axles  10  and  11  that in turn transfer drive to the tracks  8  via drive wheels  9 . 
         [0067]    The purpose of the differential is to function as a simple steering mechanism that will steer the cleaner towards a braked side, by merely braking either side of differential output drive axles  10  or  11 , via ratchet  14  and  15 , the un-braked output axle will in turn accelerate due to the gear ratio of the differential. This acceleration on one side assists in overcoming drag created on the braked side especially when using tracks. Under normal operating conditions on the pool floor, a cam  7  system will control the ratchet mechanism  14  and  15  to steer the cleaner in a pre-programmed manner. The cam  7  in this case receives input via a worm gear  16 , which is attached to the drive mechanism. 
         [0068]    Different cam profiles will create different steering patterns to accommodate various factors inherent in a specific pool design. In the preferred design, the cam can easily be replaced by clipping different cam profiles onto the cam shaft. In  FIGS. 4 and 5 , with suction applied and turbine rotating, cam  7  is in a position where both engagement arms  17  and  18  on shaft  19  are disengaged from the two ratchets  14  and  15 . The cleaner will progress in a normal forward motion in a straight line. As cam  7  continues clockwise rotation, it will rotate to a position as depicted in  FIGS. 6 and 7 , where the spring or flotation biased sliding link  20  will keep the link in contact with recessed surface on cam  7 , steering link  20  is connected to shaft  19  via pin  21 . In turn arm  17  will now engage ratchet  14 . As soon as arm  17  engages ratchet  14 , drive axle  11  will stop its rotation at side  22 . However, opposing drive axle  10  will accelerate in the direction of arrows  23 , therefore side  24  will be the accelerating side. As can be seen in  FIGS. 8  and  9 , continuation of the cam rotation will bring the extended lobe on cam  7  in contact with sliding link  20  thereby leading to engagement of arm  18  to ratchet  15 . Side  22  now depicts the side accelerating in direction of arrows  23  and side  24  depicts the braked side receiving no input. Thus it can be seen how the cleaner can be steered left and right by applying a braking force to either side of the differential shafts. The cleaner will steer towards the braked side. The cam profile on  7  can be optimized for various steering patterns. 
         [0069]    Reverse mechanism: Not shown in the drawings is the outer frame structure of the cleaner, but it is important to note the following parts will rely on anchoring points on the frame to be able to exert forces on their respective mechanisms: pin  25  on arm  26 , boom  27  that will fit into slots in the frame to allow for sliding of the assembly in direction of arrows  28 , spring biased directional pin  29 , and shaft  19 . 
         [0070]    In  FIGS. 10 and 11 , flippers  31  and  32  rotate with cam  7  to control the position of reverse flap activation arm  26 , which in turn will provide input to a set of links to enable flap  5  (shown in  FIGS. 12 through 17 ) to switch between two positions. Cam  7  is recessed on the inside to accommodate the two flippers; the design is such that both flippers can only rotate on their respective axis to a position where they make contact with the inner cam wall  33  of cam  7 . Flipper  32  is spring biased to rest against the inner cam wall  33  in the position as shown in  FIGS. 10 and 11 . Normal forward rotational movement of cam  7  is clockwise. Worm gear  16  provides input to cam  7 . Flipper  31  is not spring biased to one specific position, but will make use of a simple toggle mechanism to flip between positions as will be described below. It may also function by using friction to keep it in a set position determined by the mechanism. Note that one side of the flipper  31  has a raised lip, the function of which will be described below. Application of force on reverse arm  26  by flippers  31  and  32  will exert pressure on the arm  26  on point  34 . Arm  26  will now rotate on pin  25  to in turn force boom  27  to slide up or down dependant on cam rotational direction (see arrows  28 ). Arm  26  is linked to boom  27  through pin  35 . Flap  5  (shown in  FIGS. 12 through 17 ) is in turn linked to boom  27  by pin  36  through slot  37 . Cut-out slots  37  and  38  are necessary to allow movement of the various linkages. 
         [0071]    Now with reference to  FIGS. 12 through 17 , the cleaner will normally move in a forward direction as shown by arrows  39 . A cam  7  rotates clockwise to allow flipper  32  to make contact with reverse arm  26 . However flipper  32  will rotate out of the way as depicted in  FIGS. 12 and 13  to allow continuous rotation of cam  7  in clockwise direction until flipper  31  comes into contact with arm  26 , as shown in  FIGS. 14 and 15 . 
         [0072]    Note that flipper  32 , being spring biased, will return to its position resting against the inner cam wall as soon as it rotates past contact point on arm  26 . Flipper  31  in this position is prevented by the inner cam wall  33  of the cam  7  from rotating away from arm  26 , and therefore will exert directional force on arm  26 , rotating it around pin  25  to exert downward force on boom  27  in direction of arrow  40 , this in turn will provide input to pin  36  that pivots in anchor point  41 . 
         [0073]    Once position of flap  5  as depicted in  FIGS. 14 and 15  is reached, a toggle device will instantly switch flap  5  over to the position as depicted in  FIGS. 16 and 17 . The toggle device in this case will be a tensioned spring  42  anchored between points  43  and  44 . The timing has to be such that the turbine will rotate in the determined direction until flap toggles to the new position, whereupon turbine will start reverse rotation. 
         [0074]    Once in a position as depicted by  FIGS. 16 and 17 , the cleaner will reverse in direction of arrow  39 . Simultaneously, rotation of cam  7  will reverse to anti-clockwise rotation. 
         [0075]    As can be seen in  FIGS. 18 ,  19 , and  20 , flipper  32  will now rotate anti-clockwise with cam  7 . Flipper  32  is prevented from rotating away from arm  26  by inner cam wall  33  of cam  7 , which exerts force on arm  26  to move it from the position shown in  FIGS. 16 and 17  to the position shown in  FIGS. 18 ,  19 , and  20 . The linkages connected to arm  26  will in turn provide input to flap  5  to switch it back to its original position depicted in  FIGS. 12 and 13 . Cam  7  will simultaneously resume turning in a clockwise direction. 
         [0076]    However, while anti-clockwise rotation takes place, a mechanism has to move flipper  31  out of the way to allow another full three-hundred-sixty degree clockwise rotation of cam  7  before reverse rotation takes place again. This is important as the reverse mechanism must activate for a brief period only, compared to normal forward (clockwise) movement. Note that during the clockwise rotational cycle, a chamfered edge on spring biased pin  29  will allow the raised edge on flipper  31  to pass underneath while flipper is in position against the cam side walls, however the chamfered edge being directional will exert force on the raised lip on flipper  31  during the anti-clockwise cycle to rotate the flipper out of the way, as shown in  FIGS. 18 through 26 . Once cam  7  resumes clockwise rotation, flipper  31  is not positioned to exert any force on arm  26  (see  FIGS. 24 ,  25 , and  26 ), as it will merely be rotated back towards inner cam side wall upon contact with arm  26 . This places it in position to exert a force on arm  26  only after the next full clockwise rotation. This procedure will allow one brief period of anti clockwise rotation for every three-hundred-sixty degree clockwise rotation of the cam. In turn the input provided by the cam will reverse turbine rotation and therefore cleaner direction for this brief period. The abovementioned procedures will allow the cleaner to intermittently steer towards a braked side determined by cam design as well as incorporating a reverse mechanism that will, for a brief period, reverse direction of the cleaner. 
         [0077]    A further embodiment of the vortex chamber is shown in  FIGS. 27 and 28 . The main purpose of this configuration is to benefit from a simple steering device without differential. Two turbines  53  and  54  are positioned in the vortex chambers  48  and  49  well away from the direct path between inlet  1  and outlet  2 . Dual vortex chambers  48  and  49  are profiled  47  to divert flow equally to both chambers  48  and  49 , in turn the vortex created in each chamber will rotate both turbines  53  and  54  in the same direction as the formed vortex. With the dual vortex configuration, the cleaner will be steered by applying a braking force to either one of the shafts  50  and  51  on turbines  54  and  55 . In this case each turbine shaft will provide output to a set of tracks via a reduction gear system. 
         [0078]    The steering device incorporating the rotating cam and ratchet device will be similar as described with the differential. However, in this case, instead of applying a brake force to one of the differential shafts, the brake force will be applied to either one of the turbine shafts  50  or  51 . In this manner, the cleaner will steer towards the braked side. A variable flap can also be used in this configuration to reverse vortex and subsequently cleaner direction. 
         [0079]    Even though this configuration shows the two turbines at opposite sides of the in and outlet the configuration can also be such as to allow both turbines to be placed adjacent each other on one side of the vortex chamber, in this case the chamber will be similar to the one described for the single turbine. 
         [0080]      FIGS. 29 and 30  illustrates a top perspective view of the cleaner in a dual chamber, twin turbine configuration with the outer body removed to show the relation ship between the various parts. The drive train mechanisms  55 , preferably gears, drive tracks  57  that travel around drive wheels  56 . Rollers  59  are directly connected to the drive wheels  56  and/or drive train mechanisms  55 . Reverse flap  75  and steering flap  76  allow and restrict the flow of fluid into the area between inlet  1  and outlet  2  and affect the vortexes in vortex chambers  60 . Water then flows through outlet  2 . 
         [0081]    With reference to  FIGS. 31 ,  32 , and  33 , the reverse flap  75  and steering flap  76  are in a closed position. Flow arrows  64  show the direction of the water flow and vortex, as well as rotation of the turbines, in the chamber  60 . Main drive gear rotates in direction  65 , with the cleaner moving in direction  66 . In this figure, both vortex&#39;s, and thus turbines  63 , rotate in the same direction, and thus the cleaner will move forward in an approximately straight line. 
         [0082]    Under normal operating conditions on pool floor with suction applied, cleaner will continue in a straight line as depicted in  FIGS. 31 ,  32 , and  33 . The steering flap  76  is biased towards a closed position by a small float  78  integrated within the steering flap  76 . When the cleaner transitions to a vertical position, such as on a pool wall or step area, the float  78  in steering flap  76  will bias steering flap  76  to the open position as seen in  FIGS. 34 and 35 , thereby allowing a very small flow volume to enter through intake orifice  68 , with resulting interference in the flow intake channel  1 . This disruption of flow will in turn slow down or stop the vortex and turbine in one of the dual chambers  60 , depicted by cross  67  in  FIGS. 34 and 35 . The smaller orifice  68 , the less the disruption of the formed vortex within the chamber  60  thus resulting in slowing down rather than completely stopping the turbine. 
         [0083]    The resulting slow down or stopping of the turbine and gear train in one of the dual chambers shown by  60  will not affect the rotation of the vortex and subsequent turbine rotation in the other dual chamber, see arrows  64  in  FIGS. 34 and 35 . The side not affected will therefore continue in direction of arrow  66 , whereas the opposite side will receive no or less input from the turbine depending on size of orifice  68 , and the cleaner will steer towards the side where turbine is stopped or slowed down. This steering function is important since it is desirable to prevent the cleaner from reaching the surface of the water and sucking air into the cleaner. 
         [0084]    Tests have shown that a very small orifice is all that is needed to influence the flow pattern sufficiently such that vortex will come to a standstill in the affected chamber. This is significant in that the cleaner should still have sufficient flow through the inlet  1  and through outlet  2  to adhere to the pool surfaces when the reverse or steering function is activated. Preferably, a mechanical cam device, similar to that described above, activates the steering flap if desired when the cleaner is in a horizontal position. If desired, a second flap opposite the first will disrupt vortex in the opposing chamber thereby allowing steering effect towards both directions. In such instance, it speaks for itself that only one of the steering flaps will be engaged at any one time whether by flotation or other means. 
         [0085]    In  FIGS. 36 through 39 , the reverse flap  75  is in an open position, thereby allowing a small volume of flow to enter through orifice  77  in the direction depicted by the corresponding arrow. The resulting interference to the flow pattern through inlet  1  will cause a deflection of the flow from inlet  1  to outlet  2  to the extent that the formed vortex within both chambers  60  will be reversed, as shown by flow directional arrows  64 . The resultant reversed vortex and turbine rotation and drive gear, as shown by arrow  65 , will have the effect that cleaner will reverse direction, as shown by directional arrow  66 . 
         [0086]    As can be seen in the detailed views of  FIG. 36 through 39 , the reverse flap  75  will not cut off the flow volume through inlet  1 ; rather, reverse flap  75  will only partially intrude into the inlet  1 . Note that there has to be enough flow through inlet  1  to keep the cleaner adhered to pool surfaces when the reverse mechanism is activated. Preferably, a mechanical cam device, similar to that described above, activates the reverse flap  75 . 
         [0087]    Even though this configuration shows the two turbines at opposite sides of the in and outlet, the configuration can include both turbines to be placed adjacent to each other on one side of the vortex chamber, wherein the chamber will be similar to the one described for the single turbine. 
         [0088]      FIG. 40  is a bottom perspective view of the cleaner of  FIG. 29 . The bottom of the clean includes a curved plate  82 . Curved plate  82  includes an opening for inlet  1 . The shape of the curved plate  82  promotes the flow of fluid from underneath the cleaner to the inlet  1 . 
         [0089]    It should be understood that while the preferred embodiments of the invention are described in some detail herein, the present disclosure is made by way of example only and that variations and changes thereto are possible without departing from the subject matter coming within the scope of the following claims, and a reasonable equivalency thereof, which claims I regard as my invention. 
         [0090]    All of the material in this patent document is subject to copyright protection under the copyright laws of the United States and other countries. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in official governmental records but, otherwise, all other copyright rights whatsoever are reserved.

Summary:
A suction type turbine-driven pool-cleaners utilizing vortex turbines to propel and steer the pool cleaner is disclosed. The cleaner includes a housing for one or more vortex-turbine mechanisms, each with a chamber and a turbine, tracks for movement over submerged surfaces, a differential mechanism for steering purposes, a reverse of inlet flow mechanism, a cam design for engagement of steering and reversing mechanisms, a means of controller inlet flow for steering purposes, and a means of controlling flow for reversing direction of cleaner movement.