Abstract:
A swim current generator apparatus includes an enclosure and a motor shroud, the motor shroud enclosing a motor coupled to a propeller and having openings therein to permit the intake and discharge of water by the propeller, wherein the motor shroud is moveable between a retracted position within the enclosure and an extended position outside the enclosure.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of Provisional Patent Application No. 61/514,666, filed Aug. 3, 2011. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates generally to water exercise equipment, and more particularly to portable swim current generating devices. 
         [0003]    Conventional distance swimming environments such as Olympic pools, lakes and oceans are not convenient to many swimmers. One alternative is a swim current generator that produces a moving flow of water so that one could swim in a stationary position. Often termed “swim spas”, these are costly and require a permanent or semi-permanent installation with continuous maintenance. Further, these devices cannot be easily moved or stored without disassembly. Further, more portable devices that can be installed in an existing pool have a very “commercial” appearance, therefore needing to be stored out of sight when not in use. 
         [0004]    Accordingly, there is a need for a portable swim current generator. 
       BRIEF SUMMARY OF THE INVENTION 
       [0005]    This need is addressed by the present invention, which provides a portable swim current generator for existing pools that, when stored, resembles a decorative patio storage container. 
         [0006]    According to one aspect of the invention, a water propulsion apparatus for a swim current generator, includes: a lift frame; a belt having first and second ends, the belt being configured to transmit both tension and compression forces and being capable of bending in one plane, wherein the belt is slidably mounted in the lift frame so as to be moveable between extended and retracted positions; a motor shroud coupled to one end of the belt, the motor shroud enclosing a motor coupled to a propeller, the motor shroud having openings therein to permit the intake and discharge of water by the propeller; and an actuator coupled to the lift frame and the belt, wherein the actuator is configured to move the belt between the extended and retracted positions. 
         [0007]    According to another aspect of the invention, a swim current generator apparatus includes: an enclosure; and a motor shroud, the motor shroud enclosing a motor coupled to a propeller, and having openings therein to permit the intake and discharge of water by the propeller, wherein the motor shroud is moveable between a retracted position within the enclosure and an extended position outside the enclosure. 
         [0008]    According to another aspect of the invention, a swim current generator apparatus includes: an enclosure; a lift frame disposed inside the enclosure; a belt having first and second ends, the belt being configured to transmit both tension and compression forces and being capable of bending in one plane, wherein the belt is slidably mounted in the frame so as to be moveable between extended and retracted positions; a motor shroud coupled to the one end of the belt, the motor shroud enclosing a motor coupled to a propeller, the motor shroud configured to bear against a wall of a swimming pool and having openings therein to permit the intake and discharge of water by the propeller; and an actuator coupled to the frame and the belt, wherein the actuator is configured to move the belt between the extended and retracted positions. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The invention may be best understood by reference to the following description taken in conjunction with the accompanying drawing figures in which: 
           [0010]      FIG. 1  is a perspective view of a portable swim current generator constructed according to one aspect of the present invention, in the stored position; 
           [0011]      FIG. 2  is another perspective view of a decorative portable swim current generator in the stored position as referenced in  FIG. 1 ; 
           [0012]      FIG. 3  is a cut-away side view of the swim current generator with its componentry in a “stored” position; 
           [0013]      FIG. 4  is a cut-away side view of the swim current generator with its componentry in an “in use” position; 
           [0014]      FIG. 5  is a top plan view of the swim current generator with its componentry in the “stored” position with an access lid open; 
           [0015]      FIG. 6  is a top plan view of the swim current generator and a swimmer while “in use”; 
           [0016]      FIG. 7  is a front perspective view of an alternative swim current generator constructed in accordance with an aspect of the present invention; 
           [0017]      FIG. 8  is a rear perspective view of the swim current generator of  FIG. 7 ; 
           [0018]      FIG. 9  is a bottom perspective view of the swim current generator of  FIG. 7 ; 
           [0019]      FIG. 10  is an exploded perspective view of the swim current generator of  FIG. 7 ; 
           [0020]      FIG. 11  is a top perspective view of the swim current generator of  FIG. 7  with several components removed; 
           [0021]      FIG. 12  is a bottom perspective view of the swim current generator of  FIG. 7  with several components removed; 
           [0022]      FIG. 13  is a top perspective view of a lift apparatus of the swim current generator of  FIG. 7 ; 
           [0023]      FIG. 14  is an exploded perspective view of a motor shroud of the swim current generator of  FIG. 7 ; 
           [0024]      FIG. 15  is a side view of the swim current generator of  FIG. 7  in an extended or “in use” position; 
           [0025]      FIG. 16  is a perspective view of the swim current generator of  FIG. 7  in an extended or “in use” position; and 
           [0026]      FIG. 17  is a top view of the swim current generator of  FIG. 7  in an extended or “in use” position adjacent a swimming pool. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0027]    Referring to the drawings wherein identical reference numerals denote the same elements throughout the various views, in  FIG. 1  there is shown a perspective view of a decorative portable swim current generator enclosure  11  showing a hinged access lid  10 , decorative side  12 , decoratively matching motor shroud bottom  14 , roller  16 , roller  18 , and swivel caster  20 . 
         [0028]    In further detail, still referring to  FIG. 1 , the hinged access lid  10  is sufficiently wide and long enough to fully cover the enclosure  11 . The enclosure  11  dimensions are sufficient to house all componentry. For example its approximate dimensions may be 91 to 120 cm (36 in. to 48 in.) long, 45 to 60 cm (18 in. to 24 in.) wide, and 45 to 60 cm (18 in. to 24 in.) tall. The enclosure  11  includes roller  16  and roller  18  located on the bottom of enclosure  11  near the corners adjacent to the motor shroud bottom  14 . Also the enclosure  11  may have swivel caster  20  located opposite end of roller  16 . 
         [0029]    Referring now to  FIG. 2 , there is shown another perspective view of the decorative portable swim current generator enclosure  11  showing a hinged access lid  10 , hinge  36 , hinge  38 , hinge  40 , handle  28 , decorative end  26 , roller  18 , swivel caster  30 , and swivel caster  20 . 
         [0030]    In further detail, still referring to the invention in  FIG. 2 , the enclosure  11  has a handle  28  located on decorative end  26 , and may have swivel casters  30  and  32  also attached to bottom of enclosure  11  on decorative end  26 . Shown also is roller  18  located opposite decorative end  26  on lower corner. 
         [0031]    The decorative enclosure  11  may be made of wood, plastic, fiberglass, metal or any other sufficiently rigid and strong materials. Further, the various components of the decorative enclosure  11  can be made of different materials. 
         [0032]    Referring now to  FIG. 3 , there is shown a view of the decorative enclosure  11  with componentry arranged in the stored position including speed control head  44 , speed selector handle  46 , support shaft  48 , battery cable  50 , three stage battery charger  52 , battery enclosure  54 , sliding carriage  56 , carriage roller  58 , carriage roller  60 , hinge point  62 , height adjustment knob  64 , motor shroud  66 , and motor/propeller assembly  68 . Collectively, the sliding carriage  56  and the attached pivotable support shaft  48  constitutes a lift apparatus for the motor shroud  66 . Collectively, the lift apparatus, the motor/propeller assembly  68 , and the motor shroud  66  define a water propulsion apparatus. 
         [0033]    In  FIG. 3 , the componentry is shown in a compact stored position in its decorative enclosure  11  that can be easily moved about. Each component is explained further with reference to  FIG. 4 . 
         [0034]    In  FIG. 4 , the decorative portable swim current generator is shown with the componentry in the “in use” position. In further detail, the enclosure  11  is shown resting on a pool deck  100  within about 15 cm (6 in.) of the pool wall  98  in preparation for use. In further detail, the sliding carriage  56  has been moved towards the open end of the decorative enclosure  11  using carriage rollers  58  and  60 , thus, allowing the motor support shaft  48  to be rotated 90 degrees at hinge point  62  from the horizontal “stored” position to a vertical, “in use” position. Further, it is shown that the height adjustment  64  is used to lower the motor assembly including the speed control head  44 , speed adjustment handle  46 , the motor support shaft  48 , the motor shroud  66 , and the motor/propeller assembly  68  so as to position the top of the motor shroud  66  at the pool water surface level  95 . In further detail, the deep cycle 12 volt battery that is contained in the battery enclosure  54  and charged using the three stage battery charger  52  when not in use is connected to the speed control head  44  by a the battery cable  50  sending power through the motor support shaft  48  to the motor/propeller assembly  68 . At this stage, the user can initiate and control a flow of water away from the pool wall  98  using the speed control handle  46 , thus producing a water current in which the user can swim without lateral movement. This allows for simulated, continuous, distance swimming in an otherwise limited body of water. Upon termination of use, the process is reversed and all componentry is returned to its “stored” position as shown in  FIG. 3 . The bottom of the motor shroud  66 , when locked into the stored position, completes a congruent, decorative, exterior appearance of the enclosure  11 . 
         [0035]      FIG. 5  is a top view of the decorative portable swim current generator in the “stored” position in its decorative enclosure  11  with the access lid  10  open and supported by the lid support strap  104  and hinges  36 ,  38 , and  40 . Further, the componentry arrangement is displayed including the speed control head  44 , the speed control handle  46 , the support shaft  48 , the battery cables  50 , the sliding carriage  56 , the three stage battery charger  52 , battery enclosures  54 , height adjustment knob  64 , motor/propeller assembly  68 , and motor shroud  66  shown completing the fourth side of the rectangular decorative enclosure  11 . 
         [0036]    In  FIG. 6 , the decorative, portable, swim current generator is shown from a top view while in use. In more detail, the portable swim current generator is shown with the decorative enclosure  11  located adjacent to the pool edge  98  with motor assembly  68  and motor shroud  66  in the “in use” position. Further, a swimmer “S” is shown in the swim current “C” with the direction of flow of the swim current indicated as outward from the pool wall  98 . In further detail, the direction of the inflow or return flow “R” is shown entering the sides of the motor shroud  66 . Because the thrust forces generated by the motor/propeller assembly  68  act against the pool wall  98 , the swim current generator does not need to be anchored to the pool deck  100  or pool wall  98 . 
         [0037]      FIGS. 7-17  illustrate an alternative portable swim current generator  200  constructed according to another aspect of the present invention. The exterior components of swim current generator  200  include several panels  202 A- 202 D, including a rear panel  202 A, opposed side panels  202 B and  202 C, and a top panel (or lid)  202 D. 
         [0038]    The panels  202 A- 202 D may be constructed from any rigid material, such as wood, plastic, composites, or metal. Preferably they are made from a material that is water and moisture resistant, for example polyvinylchloride (PVC). 
         [0039]    The panels  202 A- 202 D are arranged in a generally rectangular shape. The forward end of the swim current generator  200  is open, exposing a motor shroud  204  in a retracted or stowed position. 
         [0040]    The top panel  202 D is mounted by a hinge  206  and is pivotable between a horizontal closed position (shown in  FIG. 7 ) and an open position which exposes internal components of the swim current generator  200 , described in more detail below. 
         [0041]    The panels  202 A- 202 D are mounted to a frame  208  which is best seen in  FIG. 10 . The frame  208  is generally in the form of a rectangular box, and includes a pair of spaced-apart rectangular side frames  210  interconnected by several crossmembers  212 . The frame  208  may be constructed from any rigid material, such as wood, plastic, composites, or metal. Preferably it is made from a material that is water and moisture resistant. In the illustrated example, the frame  208  is built up from stainless steel members welded together. 
         [0042]    collectively the frame  208  and the attached panels  202 A- 202 D define an enclosure that that mounts, surrounds, and protects the operating components of the swim current generator  200  while presenting a pleasing exterior appearance. 
         [0043]    A set of wheels  213  (best seen in  FIG. 9 ) is mounted to the bottom of the frame  208  and allows the swim current generator  200  to be rolled around on a pool deck or other surface. The wheels  213  may include a combination of fixed and castering units, so as to permit steering and maneuvering as required. 
         [0044]    The frame  208  carries a lift apparatus  214  as shown in  FIGS. 10-13 . A pair of fixed, parallel, spaced-apart rails  216  are secured to the frame  208  (one of the rails  216  is removed for clarity in  FIGS. 11-13 ). The rails  216  extend in a longitudinal direction and collectively define a lift frame. Each rail  216  has a generally “C”-shaped cross-section with a web and two laterally-extending flanges. A portion of the flange is cut back on the forward end of each rail  216 . The forward ends of the rails  216  join an L-shaped crossmember  218 . The crossmember  218  also carries at least one guide element adapted to help transition movement of a belt  230  from horizontal to vertical and vice-versa, for example at least one ramp or at least one roller. In the illustrated example, a pair of spaced-apart guide roller assemblies  220  are provided (see  FIG. 13 ). Each guide roller assembly  220  includes a generally triangular bracket  222  which carries a lower roller  224  and an upper roller  226 . 
         [0045]    A plurality of slats  228  are carried between the rails  216 . Each slat  228  is generally rectangular and extends laterally from one rail  216  to the opposite rail  216 . The slats  228  may be constructed of any rigid material such as wood, plastic, composites, or metal. Preferably they are made from a material that is water and moisture resistant, and that also has low friction. For example, they may be made from a polymer such as PVC. 
         [0046]    The slats  228  are coupled together in such a way that they collectively form a belt  230  which is capable of transmitting both tension and compression forces, and such that the slats  228  can bend, flex, or pivot along the lateral joints between adjacent slats  228 . In other words, the belt  230  is capable of bending in one plane. In the illustrated example, the slats  228  are coupled together by a pair of flexible straps  232  (see  FIG. 12 ) running along the bottom surfaces of the slats  228 . The straps  232  are attached to each slat  228 , for example with the illustrated fasteners, and may be made from any tough, flexible material, such as aramid fibers available under the KEVLAR brand name. Alternatively, the assembly of slats  228  could be fastened together by conventional hinges (not shown) or could incorporate integral hinges. In either case, the straps  232  would not be necessary. The belt  230  is able to slide between a retracted or stowed position (shown in  FIG. 7 ) and an extended or “use” position, shown in  FIG. 16 . 
         [0047]    As seen in  FIG. 14 , the motor shroud  204  is generally in the form of a cube and includes several plates  234 A- 234 E, more specifically particular a bottom plate  234 A, a back plate  234 B, a pair of opposed side plates  234 C, a top plate  234 D, and a front plate  234 E. As used herein, the direction terms “top”, “bottom”, etc. refer to the motor shroud  204  in the retracted or stowed position. Such terms are for relative reference purposes only. Some or all of the plates  234 A- 234 E have an open area provided by an array of holes or an open gridwork. In the specific example illustrated, the back plate  234 B and the bottom plate  234 A are solid, while the remaining plates  234 C- 234 E each have a substantial open area provided by an array of holes or an open gridwork. The plates  234 A- 234 E may be constructed of any rigid material, such as wood, plastic, composites, or metal. Preferably they are made from a material that is water and moisture resistant. For example, they may be made from a polymer such as PVC, and may be assembled to each other by fasteners such as the illustrated screws, or by adhesives or mechanical joints. 
         [0048]    A motor  236  is disposed within the motor shroud  204  and carries a propeller  238 . In the illustrated example, the motor  236  and propeller  238  are identical to those used in commercially-available boat trolling motors. The motor  236  is mounted to the back plate  234 B with a mount  240 . A cup-shaped thrust plate  241  may be mounted between the motor  236  and the bottom wall  234 A to support the motor  236  and transfer thrust loads from the motor  236  to the bottom wall  234 A. The motor  236  is oriented such that it will discharge water through the top plate  234 D in operation. 
         [0049]    The motor shroud  204  is sized and shaped so as to be able to rest on, and slide relative to, the forward portions of the rails  216 . The bottom plate  234 A is coupled to the belt  230  by the straps  232 , and mechanically functions as one of the slats  228 . Collectively, the motor shroud  204  with the motor  236  and propeller  238  and the lift apparatus define a water propulsion apparatus. 
         [0050]    Optionally, a pair of rollers  242  are mounted on an axle  244  which runs laterally along the bottom plate  234 A at the intersection of the bottom plate  234 A and the front plate  234 E. 
         [0051]    An actuator  246  (see  FIG. 12 ) is disposed under the belt  230  and is mounted in a stationary position relative to the frame  208 . In the illustrated example the actuator  246  is a commercially-available linear type including a center rail  248 , an electric drive unit  250 , and a carriage  252  which is moveable along the length of the center rail  248  in response to operation of the drive unit  250 . The carriage  252  is coupled to the slats  228  such that movement of the carriage  252  drives the belt  230  along the rails  216 . 
         [0052]    A suitable electrical power source for the motor  236  and the actuator  246  is provided. Any electrical power source that will operate the motor  236  and the actuator  246  may be used. For example, depending on the type of motor  236  and actuator  246 , conventional AC line current may be routed through the enclosure directly to those components. As another example, a commercially-available power supply that accepts AC line current and outputs low-voltage DC current for the motor  236  and actuator  246  may be placed either inside the enclosure or at a remote location and connected to the enclosure through low-voltage cabling. In the illustrated example a pair of 12 Volt deep-cycle marine batteries  254  are mounted in a rear compartment  256  of the enclosure (see  FIG. 10 ) and wired in series to provide 24 Volt power. A hinged lid  258  provides access for maintenance or repair. A commercially-available charger  260  is mounted in the rear compartment  256 . The charger  260  is configured to be connected to a conventional power source, such as conventional AC line current, and providing charging current to the batteries  254 . An AC connector  261  for the charger  260  is accessible through the side panel  202 C (see  FIGS. 8 and 10 ). 
         [0053]    An extension control  262  is provided to operate the actuator  246 . In the illustrated example, the extension control  262  is a hand-held unit contained in a center compartment  263  disposed just under the top panel  202 D. Suitable electrical connections are made in a known matter between the batteries  254 , the extension control  262 , and the actuator  246  so that in response to a user input to the extension control  262 , power from the batteries  254  will be supplied to the actuator  246  to drive the belt  230  inward or outward depending on the specific input. While a wired unit is shown, the extension control  262  could also be operated using known wireless remote control apparatus and methods. 
         [0054]    A motor control switch  264  is mounted on one of the slats  228  and is exposed when the belt  230  is in the extended position. Suitable electrical connections are made in a known matter between the batteries  254 , the motor control switch  264 , and the motor  236  so that, depending on the setting of the motor control switch  264 , the motor  236  will either be stopped or operating at a desired speed. The motor control switch  264  may incorporate (or be connected to) a conventional motor speed control, such as a transistorized motor controller. While a wired unit is shown, the motor control switch  264  could also be operated using known wireless remote control apparatus and methods. 
         [0055]    In operation, a user would first roll the swim current generator  200  to a suitable location at the edge of a swimming pool. The top panel or lid  202 D is opened and the extension control  262  is then operated, causing the belt  230  to move to the extended position, forcing the motor shroud  204  axially out of the end of the enclosure and allowing the motor shroud  204  to roll over the guide roller assemblies  220  and drop vertically downwards into the water. As the motor shroud  204  drops downward, the slats  228  bend or pivot to permit this motion. If used, the optional rollers  242  help the motor shroud  204  roll down the vertical pool wall. 
         [0056]    Once fully extended, as seen in  FIGS. 15-17 , the motor control switch  264  can be accessed to turn the motor  236  on. As seen in  FIG. 17 , the motor  236  and propeller  238  generate a swim current “C”, flowing outward from the pool wall  98 . The direction of the inflow or return flow “R” is shown entering the sides of the motor shroud  204  (and also enters through the front panel  234 E). The thrust “T” generated by the propeller  238  causes the motor shroud  204  to move backwards against the pool wall  98 . Because the thrust force is reacted against the pool wall  98 , there is no significant thrust load on the belt  230  or the frame  208 . As a result, there is no need for any portion of the swim current generator  200  to be mounted or anchored into position on the pool deck  100 . 
         [0057]    Because of the large inlet area of the motor shroud  204 , approximately 0.39 m 2  (600 in. 2 ) in the illustrated example, the local flow velocity and pressure drop is quite low. This means there is little to no risk of a swimmer&#39;s hair being drawn into the motor shroud  204 . 
         [0058]    When the user is finished, the motor  236  can be shut off using the motor control switch  264 . The extension control  262  is then operated, causing the belt  230  to move to the retracted position, pulling the motor shroud  204  vertically out of the water. If used, the optional rollers  242  help the motor shroud  204  roll up the vertical pool wall. Once the motor shroud  204  reaches its maximum vertical height, the action of the belt  230  pulling longitudinally causes it to pivot back into position within the enclosure. The roller guide assemblies  220  and the rollers  242  enable the motor shroud  204  to pivot back into position. Once stowed (retracted), the lid  202 D can be closed and the swim current generator  200  can be rolled away on the wheels  213  for storage and/or charging as desired. 
         [0059]    The swim current generator described herein has several advantages over the prior art. It is portable and simple to use, and is safe because of the low-voltage power source. When stored, it maintains a decorative aesthetic appearance, not unlike that of a decorative poolside or patio storage container. Furthermore, the present invention can be utilized in an existing, limited swim environment in order to simulate unlimited distance swimming by producing an adjustable swim current. 
         [0060]    The foregoing has described a portable swim current generator. While specific embodiments of the present invention have been described, it will be apparent to those skilled in the art that various modifications thereto can be made without departing from the spirit and scope of the invention.