Abstract:
Embodiments of the invention provide a system and method for operating a pressure-driven pool cleaner. The system includes a hydraulic timer assembly and a venturi vacuum assembly. The method includes directing water to the hydraulic timer assembly and the venturi vacuum assembly, driving the pressure-driven pool cleaner with the hydraulic timer assembly according to a timed movement cycle including a combination of backward movement and forward movement, and suctioning debris with the venturi vacuum assembly. The venturi vacuum assembly is independent of the hydraulic timer assembly so that suctioning occurs during the backward movement and the forward movement.

Description:
BACKGROUND 
     Automatic swimming pool cleaners include components for driving the pool cleaners along the floor and sidewalls of a swimming pool, either in a random or deliberate manner. For example, conventional pressure side cleaners and suction cleaners often use hydraulic turbine assemblies as drive systems to drive one or more wheels. Robotic cleaners often include a motor or other mechanical system powered by an external power source to drive one or more wheels. 
     With respect to pressure side cleaners and suction cleaners, vacuum systems of the cleaners (e.g., to vacuum debris from the floor and sidewalls and deposit the debris into a debris bag or debris canister) are often integrated with the drive systems. As a result, changes occurring in the drive system, such as turning or reversing motion, can affect the vacuum system. In some conventional pool cleaners, vacuum systems are only capable of vacuuming debris during forward motion of the drive system. 
     With respect to robotic cleaners, scrubber assemblies are often used as wheels for driving the cleaners. The scrubber assemblies also provide assistance to the vacuum systems by agitating debris along the surfaces traveled by the cleaner to facilitate debris pick-up. These types of pool cleaners cannot operate without the scrubber assemblies present because they are an essential part of the driving systems. 
     SUMMARY 
     Some embodiments of the invention provide a pool cleaner including a housing, a supply mast, and a distributor manifold in fluid communication with the supply mast. The pool cleaner also includes a timer disc assembly with at least a first outlet port, a second outlet port, and a third outlet port. The timer disc assembly is capable of receiving pressurized fluid from the distributor manifold and redirecting the pressurized fluid to at least one of the first outlet port, the second outlet port, and the third outlet port. The pool cleaner further includes a first thrust jet in fluid communication with the first outlet port, a second thrust jet in fluid communication with the second outlet port, and a third thrust jet in fluid communication with the third outlet port. The first thrust jet is positioned along the housing to direct pressurized fluid away from the rear of the housing to assist in forward motion of the pool cleaner. The second thrust jet is positioned along the housing to direct pressurized fluid away from the front of the housing to assist in backward motion of the pool cleaner. The third thrust jet is positioned along the housing to direct pressurized fluid away from the side of the housing to assist in turning motion of the pool cleaner. 
     According to some embodiments, a pool cleaner includes a chassis, a housing supported by the chassis, at least one drive wheel supported by the chassis, and a turbine assembly which rotates in one of a first direction and a second direction to drive the at least one drive wheel. The pool cleaner also includes a timer disc assembly with at least one rotating timer disc. The timer disc assembly controls a flow of pressurized fluid away from the housing in a forward direction for backward propulsion assistance of the pool cleaner during a first time period, a rearward direction for forward propulsion assistance of the pool cleaner during a second time period, and a sideways direction for turning propulsion assistance of the pool cleaner during at least a portion of one of the first time period and the second time period. The timer disc assembly also controls a flow of pressurized fluid to the turbine assembly through a first opening for driving the turbine assembly in the first direction during the first time period and a second opening for driving the turbine assembly in the second direction during the second time period. 
     According to further embodiments, a timer disc assembly for a pool cleaner includes an outer housing, a plurality of outlet ports extending through the outer housing, and a rotating timer disc positioned against an inner surface of the outer housing adjacent to the plurality of outlet ports. The timer disc assembly also includes at least one port seal liner positioned between one of the plurality of outlet ports and the rotating timer disc. The at least one port seal liner includes a liner piece in contact with the rotating timer disc and an elastomeric piece. 
     Some embodiments of the invention provide a method for operating a pressure-driven pool cleaner. The method includes providing the pressure-driven pool cleaner with a distributor manifold, a hydraulic timer assembly, and a venturi vacuum assembly. The method also includes receiving water from one of a pool pump and a booster pump into the distributor manifold and directing the water from the distributor manifold to the hydraulic timer assembly and the venturi vacuum assembly. The method further includes driving the pressure-driven pool cleaner with the hydraulic timer assembly according to a timed movement cycle including a combination of backward movement and forward movement and suctioning debris with the venturi vacuum assembly. The venturi vacuum assembly is independent of the hydraulic timer assembly so that suctioning occurs during the backward movement and the forward movement. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front perspective view of a pool cleaner according to one embodiment of the invention. 
         FIG. 2  is a rear perspective view of the pool cleaner of  FIG. 1 . 
         FIG. 3  is a partial front perspective view of the pool cleaner of  FIG. 1 . 
         FIG. 4  is a partial rear perspective view of the pool cleaner of  FIG. 1 . 
         FIG. 5A  is a side cross-sectional view of the pool cleaner of  FIG. 1 . 
         FIG. 5B  is a rear cross-sectional view of the pool cleaner of  FIG. 1 . 
         FIG. 5C  is a top cross-sectional view of the pool cleaner of  FIG. 1 . 
         FIG. 6A  is a perspective view of a lower manifold for use with a pool cleaner according to another embodiment of the invention. 
         FIG. 6B  is a side cross-sectional view of the lower manifold of  FIG. 6A . 
         FIG. 7A  is a perspective view of a scrubber assembly of the pool cleaner of  FIG. 1 . 
         FIG. 7B  is a partial perspective view of the scrubber assembly of  FIG. 7A . 
         FIG. 7C  is a partial perspective view of the pool cleaner of  FIG. 1 . 
         FIG. 8A  is a perspective view of a scrubber assembly for use with a pool cleaner according to another embodiment of the invention. 
         FIG. 8B  is a partial perspective view of the scrubber assembly of  FIG. 8A . 
         FIG. 8C  is another partial perspective view of the scrubber assembly of  FIG. 8A . 
         FIG. 9  is a partial bottom perspective view of the pool cleaner of  FIG. 1 . 
         FIG. 10  is a perspective view of a timer assembly of the pool cleaner of  FIG. 1 . 
         FIG. 11  is a side cross-sectional view of a timer disc assembly of the timer assembly of  FIG. 10 . 
         FIG. 12  is an exploded perspective view of the timer assembly of  FIG. 11 . 
         FIG. 13  is a perspective cross-sectional view of a turbine assembly of the pool cleaner of  FIG. 1 . 
         FIG. 14  is a perspective view of a timer valve gear box of the timer assembly of  FIG. 10 . 
         FIG. 15  is a partial perspective view of the timer valve gear box of  FIG. 14 . 
     
    
    
     DETAILED DESCRIPTION 
     Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. 
     The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention. 
       FIGS. 1 and 2  illustrate a pool cleaner  10  according to one embodiment of the invention. The pool cleaner  10  can be a pressure-side pool cleaner powered by a filtration pump of a swimming pool system or a booster pump and can be capable of automatically cleaning debris from a floor and/or sides of a swimming pool or spa. The pool cleaner  10  can include precise directional control, enhanced suction, and additional scrubbing capabilities. 
     As shown in  FIGS. 1 and 2 , the pool cleaner  10  can include a cover assembly  12 , including a front cover  14 , a rear cover  16 , a front grill  18 , a top cover  20 , a bottom cover  22 , and two side covers  24 ,  26 . The pool cleaner  10  can also include two front wheel assemblies  28  and two rear wheel assemblies  30 . The front wheel assemblies  28  can include wheels  32  rotatable about stationary axles  34  via hub assemblies  35 , as shown in  FIGS. 3 and 4 . The front wheel assemblies  28  can include inner teeth  36  and can each be driven by a rotating shaft  38  of a hydraulic turbine assembly  40  (as shown in  FIG. 4 ) that engages the inner teeth  36 . In one embodiment, the outer portion of each wheel  32  can be substantially smooth. In another embodiment, the outer portion of each wheel  32  can include treads for better traction across the pool surface. The rear wheel assemblies  30  can freely rotate about stationary rear axles  42  via hub assemblies  43  and can also include substantially smooth or treaded outer portions. The four-wheel design of the pool cleaner  10  can provide better stability and resist tipping, in comparison to conventional three-wheel pool cleaners. In some embodiments, the cover assembly  12  and the wheel assemblies  28 ,  30  can be constructed of plastic or similar materials. In addition to the hydraulic turbine wheel assembly  40 , the motion of the pool cleaner can be driven by water forced through thrust jets and/or thrust jet ports, such as a rear thrust jet  44 , as shown in  FIG. 2 , or a front thrust jet port  46 , as shown in  FIG. 1 . 
       FIGS. 3 and 4  illustrate the pool cleaner  10  with the cover assembly  12  and wheel assemblies  28 ,  30  removed. As shown in  FIGS. 3 and 4 , the pool cleaner  10  can include a chassis  48 , which can provide structural support for the cover assembly  12  and other components of the pool cleaner  10 , as well as the stationary axles  34 ,  42  for the front wheel assemblies  28  and the rear wheel assemblies  30 , respectively. As shown in  FIGS. 3 and 4 , the chassis  48  can include receiving holes  50  for receiving fasteners in order to couple the cover assembly  12  to the chassis  48 . For example, at least some of the components of the cover assembly  12  can be coupled to the chassis  48  using fasteners and the receiving holes  50 . In addition, some of the components of the cover assembly  12  can be supported by the chassis  48  and held in place by other components of the cover assembly  12 . The pool cleaner  10  can also include turn thrust jets  52  (e.g., in fluid communication with thrust jet ports  53  on the cover assembly  12 , as shown in  FIG. 2 ), a float  54 , a supply mast  56  connected to a distributor manifold  58 , a sweep hose attachment  60  for receiving a sweep hose (not shown), a venturi vacuum assembly  62 , a timer assembly  64 , and a scrubber assembly  66 . Also, in some embodiments, an inner side of the front grill  18  can include a front thrust jet (not shown) in fluid communication with the front thrust jet port  46 . The front thrust jet can be integral with the front grill  18  or a separate piece. 
     The supply mast  56  can be coupled to a hose (not shown) that receives pressurized water from the pool pump or booster pump. The supply mast  56  can direct the pressurized water to the distributor manifold  58  for further distribution to specific components of the pool cleaner  10 . For example, as shown in  FIGS. 5A-5C , the distributor manifold  58  can at least include an inlet  68  coupled to the supply mast  56 , an outlet  70  fluidly connected to the sweep hose attachment, one or more outlets  72  fluidly connected to the venturi vacuum assembly  62 , and one or more outlets  74  fluidly connected to the timer assembly  64 . In some embodiments, as shown  FIGS. 3 and 4 , the distributor manifold  58  can be substantially ring-shaped and can surround the venturi vacuum assembly  62 . In some embodiments, the supply mast  56  can be coupled to the distributor manifold  58  by a press-fit and/or by fasteners. In addition, in some embodiments, the supply mast  56  can also, or alternatively, be coupled to the chassis  48  by a press-fit and/or fasteners. 
     In some embodiments, the venturi vacuum assembly  62  can vacuum, or pick up, debris from the pool surface and deposit the debris in a debris collection system (not shown) coupled to a suction mast  76 . As shown in  FIGS. 5A-5B , the venturi vacuum assembly  62  can include the suction mast  76 , one or more venturi nozzle assemblies  78 , and an attachment collar  80 . The suction mast  76  can be substantially cylindrical with an open bottom end  82  and an open top end  84 . The attachment collar  80  can be removably coupled to the open top end  84  of the suction mast  76  and can be used to secure the debris collection system, such as a debris bag or a debris canister, to the suction mast  76  for collecting the retrieved debris. The venturi nozzle assemblies  78  can be coupled to or integral with the suction mast  76  near the open bottom end  84  and can each include one or more jet nozzles  86  which provide a flow of pressurized water (e.g., from the distributor manifold  58 ) up through the suction mast  76  in order to create a pressure difference, or venturi effect, within the suction mast  76 . The pressure difference can cause a suctioning effect to vacuum up debris directly under and surrounding the open bottom end  82  of the suction mast  76 . In one embodiment, the suction mast  76  can include cut-outs  87  for receiving the nozzle assemblies  78 , as shown in  FIG. 5A . In addition, in some embodiments, the bottom cover  22  can provide a substantially conical opening  88  that tapers inward toward the open bottom end  82  of the suction mast  76 , as shown in  FIGS. 5A-5B . 
     Conventional pressure-side pool cleaners generally include a single-stage venturi system, where the jet nozzles are positioned along a single horizontal plane. In some embodiments, as shown in  FIG. 5B , the venturi vacuum assembly  62  can provide multiple stages of jet nozzles  86 , where each stage is along a horizontal plane and is vertically offset from another stage. The multi-stage venturi vacuum assembly  62  can more efficiently suction debris from the pool surface, through the suction mast  76 , and into the debris bag or canister compared to single-stage venturi systems. More specifically, the multi-stage venturi vacuum assembly  62  can increase water flow through the suction mast  76 , and in turn provide improved suction for debris beyond the limits of size and geometry for single-stage venturi systems. For example, a first stage of jet nozzles  86  can lift debris into the suction mast  76  and a second stage of jet nozzles  86  can help move the debris into the debris collection system. In addition, the conical opening  88  tapering outward from the open bottom end  82  can allow larger debris to enter the venturi vacuum assembly  62 . 
       FIGS. 5A-5B  illustrate the venturi vacuum assembly  62 , according to one embodiment of the invention, with two stages of jet nozzles  86 . Each stage can include two jet nozzles  86  directed at an upward angle. For example, the first stage of jet nozzles  86  can be positioned adjacent to the conical opening  88  of the bottom cover  22 , below the open bottom end  82  of the suction mast  76 . The angles of the two jet nozzles  86  of the first stage can intersect at a point P 1  slightly above conical opening  88  (e.g., within the suction mast  76 ), as shown in  FIG. 5B . The second stage jet nozzles  86  can be positioned around the periphery of the suction mast  76 , near the open bottom end  82  of the suction mast  76  (e.g., vertically above the first stage jet nozzles  86 ). The angles of the two jet nozzles  86  of the second stage can intersect at a point P 2  that is above the intersection point P 1  of the first stage jet nozzles  86 . In operation, pressurized water is forced through the first stage venturi jets  86  for initial suction of the debris directly under and/or around the conical opening  88 . Pressurized water is also forced through the second stage venturi jets  86  for additional suction action in order to lift the debris through the suction mast  76  and into the debris collection system. 
     In some embodiments, as shown in  FIGS. 6A-6B , the venturi vacuum assembly  62  can include a separate lower manifold  90  which can be press-fit or fastened to the suction mast  76  and/or the bottom cover  22 . The lower manifold  90  can include the conical opening  88  with a first stage of jet nozzles  86 , and a cylindrical section  92 , positioned above the conical opening  88 , including a second stage of jet nozzles  86 . In such embodiments, the venturi vacuum assembly  62  can also include connector assemblies (not shown), which provide fluid pathways from the outlet ports  72  of the distributor manifold  58  to the jet nozzles  86 . In other embodiments, the jet nozzles  86  and/or the conical section  88  can be integral with the suction mast  76 . In addition, in some embodiments, the jet nozzles  86  may be flush with the conical section  88 , the suction mast  76 , and/or the lower manifold  90 , as shown in  FIGS. 5A-5B , or the jet nozzles  76  may extend outward from the conical section  88 , the suction mast  76 , and/or the lower manifold  90 , as shown in  FIGS. 6A-6B . 
     In some embodiments, as shown in  FIGS. 7A-8C , the scrubber assembly  66  can be used as an add-on cleaning feature of the pool cleaner  10 . As the pool cleaner  10  travels along the pool surface, the scrubber assembly  66  can provide sweeping and scrubbing action against the pool surface in order to lift and agitate debris. This can increase the amount of debris which is picked up by the venturi vacuum assembly  62 . The scrubber assembly  66  may be attached to the pool cleaner  10  at all times, or may be detached by a user when scrubbing is deemed unnecessary. More specifically, the pool cleaner  10  may operate without the scrubber assembly  66  attached, unlike many conventional pool cleaners with permanent scrubbers. 
     In some embodiments, the scrubber assembly  66  can include an elastomeric bristle  94  coupled to a rotary cylinder  96 . For example, as shown in  FIGS. 8A and 8B , portions of the elastomeric bristle  94  and portions of the rotary cylinder  96  can each include snap-on fittings  98  so that the elastomeric bristle  94  can be wrapped around the rotary cylinder  96  and the respective snap-on fittings  98  snapped together. As shown in  FIGS. 7B and 8C , the scrubber assembly  66  can also include a center shaft  100 , and pinion gears  102 , bearings  104 , and end brackets  106  at each end of the center shaft  100 . The end brackets  106  can each house or at least support one of the pinion gears  102  and can be coupled to the center shaft  100 . The center shaft  100  can provide support for the rotary cylinder  96  and the bearings  104  (e.g., ball bearings) can allow free rotation of the rotary cylinder  96  about the center shaft  100 . 
     The pinion gears  102  can control the rotation of the rotary cylinder  96 . More specifically, the rotary cylinder  96  can include an internal spur gear profile  108  on one or both ends, as shown in  FIGS. 7A and 8A , which can engage the pinion gears  102 . At least one of the pinion gears  102  can be engaged with a spur gear  109 , which is further engaged with the inner teeth  36  of at least one of the front wheel assemblies  28 , as shown in  FIG. 7C . As a result, forward and/or backward rotation of the front wheel assemblies  28  can drive rotation of the rotary cylinder  96  in the same direction. The pinion gear  102  can engage the spur gear  109  via a pinion gear shaft  110 . The spur gear  109  can extend through a bearing  111  positioned in the chassis  48  to engage the pinion gear shaft  110 . In addition, a bracket  113  can be positioned adjacent to the front wheel assembly  28  to support the spur gear  109 . 
     As discussed above, the scrubber assembly  66  can be removed or detached from the pool cleaner  10 . For example, the chassis  48  can include a detachable piece  115 , as shown in  FIG. 3 . The detachable piece  115  can be screwed onto or otherwise coupled to the chassis  48  around one the of the pinion gear shafts  110  (e.g., on the opposite side from the spur gear  109 ). More specifically, the detachable piece  115  can be detached from the chassis  48 , the scrubber assembly  66  can then be engaged with the spur gear  109  (e.g., to attach the scrubber assembly  66 ) or pulled away from the spur gear  109  (e.g., to detach the scrubber assembly  66 ), and then the detachable piece  115  can be reattached to the chassis  48 . In some embodiments, at least a portion of the pinion gear shaft  110  can be spring loaded (e.g., biased away from the end brackets  106 ) to aid in attachment or detachment of the scrubber assembly  66  from the pool cleaner  10 . As a result of the scrubber assembly  66  being coupled to the chassis  48  by the detachable piece  115 , the scrubber assembly  66  can be removed or attached to the pool cleaner  10  without requiring removal of one or both front wheel assemblies  28 . 
     As shown in  FIGS. 7A-8C , the pinion gears  102  can be aligned off-center from the center shaft  100 . As a result, the end brackets  106 , as well as the other components of the scrubber assembly  66 , can swing about the pinion gears  102 , allowing the scrubber assembly  66  to substantially lift itself over objects or large debris on the pool surface. Thus, the scrubber assembly  66  can provide additional floor sweeping during forward and/or reverse motion of the pool cleaner  10  without damaging the pool surface. For example, the scrubber assembly  66  can lift itself over large particles to avoid pushing such particles across the pool surface. In addition, the elastomeric bristle  94  can be soft enough to not cause wear along the pool surface. 
     The end brackets  106  of the scrubber assembly  66  can each include an arm  112  which can limit the swing or lift of the scrubber assembly  66 . In some embodiments, the arms  112  can be substantially resilient (e.g., acting as spring members). As shown in  FIG. 5A , the bottom cover  22  can include a front step  204  and a rear step  206 . The front step  204  and/or the rear step  206  can be indentations or curvatures across the length of the bottom cover  22  or indentations located only adjacent to the arms  112 . During forward movement of the pool cleaner  10 , the scrubber assembly  66  can lift over an object causing the end brackets  106  to rotate around the pinion gears  102  in a forward direction (e.g., in a counterclockwise direction relative to the side view shown in  FIG. 5A ). After a certain amount of forward rotation, the arms  112  can contact the front step  204 , thus limiting the rotation of the scrubber assembly  66 . The arms  112  can compress against the front step  204  as the pool cleaner  10  continues to move over the object and, in part due to their resiliency, can force the end brackets  106  to rotate back to their original position when the object has been passed over. In a similar fashion, during backward movement of the pool cleaner  10 , the scrubber assembly  66  can lift over an object causing the end brackets  106  to rotate around the pinion gears  102  in a backward direction (e.g., in a clockwise direction relative to the side view shown in  FIG. 5A ). After a certain amount of backward rotation, the arms  112  can contact the rear step  206 , thus limiting the rotation of the scrubber assembly  66 . Gravity and/or spring action of the arms  112  can force the end brackets  106  to rotate back to their original, resting position when the object has been passed over. 
     In some embodiments, the timer assembly  64  can control forward movement, turning, and reverse movement of the pool cleaner  10 . The timer assembly  64  can also control the timing for each movement state (e.g., forward movement, reverse movement, and one or more turning movements) of the pool cleaner  10 . As described above, the timer assembly  64  can receive water from the distributor manifold  58 . The timer assembly  64  can redirect the incoming water from the distributor manifold  58  to control the movement state of the pool cleaner  10 , as described below. 
     As shown in  FIGS. 9 and 10 , the timer assembly  64  can include a timer disc assembly  114  and a timer valve gear box  116 . The timer disc assembly  114  can provide alignment of fluid pathways between the incoming water from the distributor manifold  58  and different outlet ports  118 - 128 , as shown in  FIG. 11 , for control of the movement state of the pool cleaner  10 . The timer valve gear box  116  can provide a hydraulic timer which controls the alignment of the fluid pathways in the timer disc assembly  114  so that the pool cleaner  10  is in a specific movement state for a set or predetermined time period. 
     As shown in  FIGS. 9-12 , the timer disc assembly  114  can include an outer housing  130 , such as a top cover  132  and a bottom cover  134 . The outer housing  130  can include an inlet port  136 , as shown in  FIG. 12 , which can receive water from the distributor manifold  58  and a plurality of outlet ports  118 - 128  which can provide water to one or more locations of the pool cleaner  10 , as described below. The inlet port  136  and the outlet ports  118 - 128  can merely be holes extending through a portion of the outer housing  130 , or can also include extensions from the outer housing  130  to facilitate coupling connectors (e.g., a distributor manifold connector  138  or a chassis connection  140 ) or port elbows  142  to the outer housing  130 . In one embodiment, as shown in  FIGS. 11 and 12 , the outer housing  130  can include four outlet ports  118 - 124  extending through the top cover  132  and two outlet ports  126 ,  128  extending through the bottom cover  134 . In addition, o-rings  144  can be positioned between the port elbows  142  and the outer housing  130  so that water exiting the outlet ports  118 - 126  may only exit through the port elbows  142 . In some embodiments, some of the port elbows  142  can be substituted with stand-alone connectors or connectors integral with the chassis  48  or cover assembly  12  (not shown). 
     The outer housing  130  can be substantially sealed, for example by one or more seals  146 , press-fitting, and/or fasteners (not shown) so that water entering the inlet port  136  can only exit the outer housing  130  via the outlet ports  118 - 128 . Internal components of the timer disc assembly  114 , as further described below, can control which outlet ports  118 - 128  the water may exit from. More specifically, the internal components can periodically block or unblock one or more of the outlet ports  118 - 128  and the pool cleaner  10  can be driven in a specific movement state depending on which of the outlet ports  118 - 128  are blocked and unblocked. 
     In some embodiments, as shown in  FIGS. 11 and 12 , the timer disc assembly  114  can include one or more timer discs  148 ,  150 , a spring  152 , one or more port seal liners  154 , a pinion gear  156 , and a pinion gear shaft  158 . The timer discs  148 ,  150 , the spring  152 , the port seal liners  154 , and the pinion gear  156  can be substantially enclosed by the outer housing  130 . The pinion gear shaft  158  can extend through the outer housing  130  and into the timer valve gear box  116 . As further described below, the pinion gear shaft  158  can be rotated by components within the timer valve gear box  116 . Rotation of the pinion gear shaft  158  can cause rotation of the pinion gear  156  within the outer housing  130 , and one or both of the timer discs  148 ,  150  can be rotated by the pinion gear  156 . For example, as shown in  FIG. 11 , the larger timer disc  148  can include a toothed portion  160  engaging with the pinion gear  156 . In addition, the larger timer disc  148  can be coupled to or can engage with the smaller timer disc  150  so that both timer discs  148 ,  150  can rotate in unison. 
     Each of the timer discs  148 ,  150  can include one or more slots  162  extending through them, as shown in  FIG. 12 . The slots  162  can be located along the timer discs  148 ,  150  so that, during the respective rotations of the timer discs  148 ,  150 , the slots  162  can align with one or more of the outlet ports  118 - 128 , allowing water to exit the outer housing  130  via the respective outlet ports  118 - 128  and/or the timer discs  148 ,  150  can substantially block one or more of the outlet ports  118 - 128 , preventing water to exit the outer housing  130  via the respective outlet ports  118 - 128 . The port seal liners  154  can be positioned between the outlet ports  118 - 128  and the timer discs  148 ,  150  in order to permit water out through the outlet ports  118 - 128  only when one of the slots  162  of the timer discs  148 ,  150  is aligned with the respective outlet ports  118 - 128 . The spring  152  can substantially force the timer discs  148 ,  150  away from each other and against the outer housing  130 . This can result in a better seal between the port seal liners  154  and the timer discs  148 ,  150 . In some embodiments, as shown in  FIG. 12 , the outer housing  130  can include outlined cavities  164  which can each receive at least a portion of a port seal liner  154  in order to keep the port seal liner  154  correctly positioned adjacent to the outlet ports  118 - 128  and prevent the port seal liner  154  from moving during rotation of the timer discs  148 ,  150 . 
     In some embodiments, as shown in  FIGS. 11 and 12 , each of the port seal liners  154  can include an elastomeric piece  166  molded onto a lower density liner  168 . As the stationary port seal liner  154  is in contact with one of the rotating timer discs  148 ,  150 , the lower density liner  168  can provide less friction (e.g., from shear stresses) between the port seal liner  154  and the rotating timer disc  148 ,  150  in comparison to conventional seals only using an elastomeric piece. This can reduce the wear and increase the lifetime of the port seal liner  154 . The elastomeric piece  166  of the port seal liner  154  can act as a spring to engage the seal between the port seal liner  154  and the outlet port  118 - 128 . As shown in  FIG. 12 , each port seal liner  154  can include two holes, and as a result, can seal one or two outlet ports  118 - 128 . In some embodiments, one or more port seal liners  154  can include a single hole so that one or more outlet ports  118 - 128  can be aligned with their own respective port seal liner  154 . 
     As described above, the pool cleaner  10  can be driven in a specific movement state depending on which of the outlet ports  118 - 128  are blocked and unblocked. More specifically, some of the outlet ports  118 - 128  can lead to different thrust jets of the pool cleaner  10  so that, when an outlet port  118 - 128  is unblocked, water can exit the pool cleaner  10  through its respective thrust jet  44 ,  52  and/or thrust jet port  46 ,  53 . The thrust jets  44 ,  52  and/or the thrust jet ports  46 ,  53  can be positioned along the pool cleaner  10  to direct water outward from the pool cleaner  10  in a specific direction, providing propulsion assistance. For example, the rear thrust jet  44  can be positioned along the pool cleaner  10  to direct pressurized water away from the rear of the pool cleaner  10  to assist in forward motion. The turn thrust jets  52  and the turn thrust jet ports  53  can be positioned on either side of the pool cleaner  10  to direct pressurized water away from the side of the pool cleaner  10  to assist in turning motion. The front thrust jet can be positioned along the pool cleaner  10  to direct pressurized water away from the front of the pool cleaner  10  to assist in backward motion. 
     In addition, one or more of the outlet ports  118 - 128  can lead to the hydraulic turbine assembly  40  of the pool cleaner  10 , as further described below. Due to the sealing between the top cover  132  and the bottom cover  134 , the sealing between each of the outlet ports  118 - 128  and the port elbows  142  and/or connectors  138 ,  140 , and the minimal wear port seal liners  154  between the timer discs  148 ,  150  and the outlet ports  118 - 128 , the timer disc assembly  114  can remain substantially leak proof. As a result, water exiting through the outlet ports  118 - 128  can remain at optimal pressure, providing improved propulsion assistance as well as improved driving force for the turbine assembly  40 . 
     As described above, the pool cleaner  10  can include the first rear turn thrust jet  52 , the second rear turn thrust jet  52 , the rear thrust jet  44 , and the front thrust jet (not shown). The pool cleaner  10  can also include the thrust jet ports  46 ,  53  in fluid communication with the rear thrust jets  52  and the front thrust jet, respectively. One of the outer port elbows  142  coupled to outlet ports  118  or  124  can be fluidly connected to the rear thrust jet  44  to assist forward propulsion of the pool cleaner  10  (i.e., the forward movement state). One of the inner port elbows  142  coupled to outlet port  120  or  122  can be fluidly connected to the first turn thrust jet  52  and the other one of the inner port elbows coupled to outlet port  122  or  120  can be fluidly connected to the second rear thrust jet  52 . The slots  162  can be located on the timer disc  148  so that only one of outlet ports  120 ,  122  is unblocked at a time. As a result, when one of the outlet ports  120 ,  122  is unblocked, water will be routed to one of the turn thrust jets  52  to assist in turning the pool cleaner  10  (i.e., one of the turn movement states). The bottom port elbow  142  coupled to outlet port  126  can be fluidly connected to the front thrust jet to assist in backward propulsion of the pool cleaner  10  (i.e., the backward movement state). The timer discs  148 ,  150  can be positioned relative to each other so that when the bottom outlet port  126  is unblocked (e.g., allowing water to exit the pool cleaner  10  through the front thrust jet), all four of the top outlet ports  118 - 124  are blocked (e.g., blocking water from exiting the pool cleaner  10  via the rear thrust jet  44  or the turn thrust jets  52 ). In addition, the slots  162  can be located on the timer discs  148 ,  150  so that one of the outer outlet ports  118 ,  124  can substantially always be unblocked when one of the inner outlet ports  120 ,  122  is unblocked. 
     In some embodiments, the thrust jets  44 ,  52  can be stand-alone pieces coupled to the pool cleaner  10  or the thrust jets  44 ,  52  can be integral with the chassis  48  or cover assembly  12 . In addition, the front thrust jet can be integral with the front grill  18  so that it in direct fluid communication with the front thrust jet port  46 , and the turn thrust jet ports  53  can be aligned with the turn thrust jets  52 . As a result, the front thrust jet and the turn thrust jets  52  may not extend outward from the cover assembly  12 . Fluid connections between the port elbows  142  (and/or connectors  138 ,  140 ) and the thrust jets  44 ,  52  (and/or other inlets/outlets of the pool cleaner  10 ) can be accomplished via tubing or similar connections (not shown). In other embodiments, the front thrust jet and/or the turn thrust jets  52  can extend through the cover assembly so that the thrust jet ports  46 ,  53  are not necessary. Similarly, in other embodiments, the rear thrust jet  44  can remain enclosed within the cover assembly  12  and can align with a rear thrust jet port (not shown) along the cover assembly  12 . 
     As discussed above, one or more of the outlet ports  118 - 128  can be fluidly connected to the hydraulic turbine assembly  40  via port elbows  142 , connectors  140 , etc. to provide water pressure for driving the hydraulic turbine assembly  40  in a forward direction and/or a backward direction. The hydraulic turbine assembly  40  can include a turbine wheel  172  and the turbine shaft  38 . The turbine wheel  172  can be housed within a turbine housing  174 , which can be completely or partially separate from, or integral with the chassis  48  and/or cover assembly  12 . The turbine shaft  38  can be pinion shaped or otherwise threaded and can engage the inner teeth  36  of the front wheel assemblies  28 , as described above. Rotation of the turbine shaft  38  can thus cause the front wheel assemblies  28  to rotate and drive the pool cleaner  10 . The turbine housing  174  can include one or more openings  176 ,  178  to allow a stream of incoming water through the turbine housing  174 . This stream of incoming water can be directed toward the turbine wheel  172  to cause rotation of the turbine wheel  172 , and thus causes rotation of the turbine shaft  38 . 
     In one embodiment, as shown in  FIG. 13 , the turbine housing  174  can include a first opening  176  and a second opening  178 . The first opening  176  can be fluidly connected to an upper outer port elbow  142  so that, when the respective outlet port  118  is unblocked, water can be directed into the turbine housing  174  to drive the pool cleaner  10  in a forward motion. The second opening  178  can be fluidly connected to the lower connector  140  so that, when the respective outlet port  128  is unblocked, water can be directed into the turbine housing  174  to drive the pool cleaner  10  in a backward direction. The timer discs  148 ,  150  can be positioned relative to each other so that only one of the openings  176 ,  178  may receive incoming water at a time. In some embodiments, water can leak out from a side of the turbine housing  174  after entering one of the openings  176 ,  178  to drive the turbine wheel  172 . 
     In some embodiments, the timer valve gear box  116  can be used to drive the rotation of the timer discs  148 ,  150 . As shown in  FIGS. 14 and 15 , the timer valve gear box  116  can include a gear box housing  182 , such as a bottom plate  184  and a top cover  186  coupled together via a press-fit, fasteners (not shown), or other coupling methods, a paddle wheel  188 , a paddle wheel shaft  190 , paddle wheel bearings  192 , and a gear train  194  including a plurality of gears  196  rotatable about one or more shafts  198 . The gear box housing  182  can include an inlet  200  and an outlet  202  to allow a stream of water to flow through the timer valve gear box  116 . The paddle wheel  188  can be positioned in line with the stream of water so that the water causes rotation of the paddle wheel  188 . Rotation of the paddle wheel  188  can engage the gear train  194  to cause rotation of the gear train  194  (e.g., the paddle wheel  188  can act as the driving gear of the gear train  194 ). The number and positioning of the gears  196  can provide a desired gear ratio relative to the paddle wheel  188  to achieve a required speed and torque for running the timer discs  148 ,  150  at a desired rate. A final gear  196  of the gear train  194  can be coupled to the pinion shaft  158  of the timer disc assembly  114  via a final gear shaft  198  extending through the top cover  186 . As a result, rotation of the final gear shaft  198  can cause rotation of the timer discs  148 ,  150 . In one embodiment, a desired rotation rate of the final gear  196  can be about 0.9 revolutions per minute. Rotation rate can vary depending on the original rotation rate of the paddle wheel  188 , which is based on the incoming stream of water. As a result, changes in pool pump or booster pump output pressure can sometimes affect the rotation rate of the timer discs  148 ,  150 . 
     The timer valve gear box  116  and the timer disc assembly  114  can achieve desired cycles of forward, backward and turning movement states. The timer valve gear box  116  (e.g., the gear ratios) can be designed to achieve an optimal cycle time needed for efficient cleaning. For example, a full cycle can be considered the following: right turn, backward movement, right turn, forward movement, left turn, backward movement, left turn, forward movement. The time in each movement state can depend on the rotation of the timer discs  148 ,  150  as well as the size of the slots  162  (i.e., the amount of time each outlet port  118 - 128  is blocked or unblocked). This precise timing and movement cycle can allow the pool cleaner  10  to efficiently clean the pool in a substantially random motion, improving pool coverage and cleaning time. In addition, the timer valve gear box  116  and the timer disc assembly  114  can be independent from the venturi vacuum assembly  62 . As a result, the pool cleaner  10  can constantly vacuum debris during all movement states, in comparison to conventional pool cleaners which require a non-vacuuming period for backward and/or turning movement. 
     It will be appreciated by those skilled in the art that while the invention has been described above in connection with particular embodiments and examples, the invention is not necessarily so limited, and that numerous other embodiments, examples, uses, modifications and departures from the embodiments, examples and uses are intended to be encompassed by the claims attached hereto. The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein. Various features and advantages of the invention are set forth in the following claims.