Aquatic treadmill with reversible orientations

[0001] This application claims the benefit of U.S. Provisional Application No. 60/338,960, filed Nov. 5, 2001, which is incorporated by reference herein in its entirety.

[0002] 1. Field of the Invention

[0003] The present invention relates to personal exercise equipment and, more particularly, to aquatic treadmills.

[0004] 2. Prior Art

[0005] The advantages of therapeutic exercises with the body partially immersed in water compared to similar exercises on land have long been recognized. For example, the water medium by virtue of its higher density (relative to air) provides a buoyant effect to immersed body parts, and by virtue of its viscosity provides a damping effect to underwater motions performed when exercising. These effects combined to reduce undesired loads especially impact on the joints and the spine. Moreover, the higher density and viscosity of water provide increased resistance to exercise movements increasing muscle load at lower movement speeds thereby improving the workout rate. Nevertheless, the conventional approach to exercise equipment for underwater exercises had generally been to merely immerse exercise equipment developed for use out of water with little or no modifications. One example of this approach is disclosed in U.S. Pat. No. 5,921,892 which provides an underwater treadmill device with a driver roller and an idler roller engaging opposite ends of a treadmill belt. A hydraulic motor, positioned out of water imparts rotary motion to the drive roller. Another example is disclosed in U.S. Pat. No. 5,558,604 which provides an aquatic treadmill apparatus made up of a treadmill belt trained over a drive roller and take-up roller, a fluid drive motor and a flywheel are coupled to a common drive shaft driven by a power source outside of the water. U.S. Pat. No. 5,586,961 discloses still another example of a conventional aquatic exercise equipment that includes a plurality of exercise services. A review of the aforementioned examples will reveal very little difference between conventional under water exercise equipment and land or out of water exercise equipment counterparts. Aside from the obvious corrosion concerns of the underwater environment, conventional underwater exercise equipment does not appear to take advantage of or make concessions to the effects of the underwater environment on moving devices as well as on the body of the user. Also, conventional underwater equipment appears to have been developed with commercial use in mind, of being located in commercial exercise facilities, clubs or spas. As such, the conventional underwater exercise equipment appears best suited for hard bottom pools which are likely to be found in such facilities rather than the sand bottom pools ordinarily found at private residences. Other underwater exercise apparatus are disclosed in U.S. Pat. Nos. 5,123,641 and 5,437,588. The underwater exercise apparatus of the present invention overcomes the problem of the conventional apparatus as will be described in general detail below.

[0006] In accordance with an embodiment of the present invention, an aquatic treadmill is provided. The treadmill comprises a frame, rollers, and a belt. The rollers are rotatably connected to the frame. The belt is movably connected to the rollers, so that the belt is movable in at least one direction relative to the frame. The belt forms at least two walkway areas arranged so that the treadmill is reversibly orientable relative to a seating surface on which the treadmill is seated. One of the at least two walkway areas is accessible when the treadmill is in a first orientation, and another of the at least two walkway areas is accessible when the treadmill has a reverse orientation from the first orientation.

[0007] The foregoing aspects and other features of the present invention are explained in the following description, taken in connection with the accompanying drawings, wherein:

[0008] FIGS. 1A-1B are respectively a side and rear elevation view of a treadmill incorporating features of the present invention;

[0009] FIGS. 2A-2D respectively are a side elevation, plan, partial plan, and partial front elevation views of the treadmill with the casing removed for clarity;

[0010] FIGS. 3A-3C respectively are another side elevation, plan, and partial plan views of the treadmill with additional features removed for clarity;

[0011] FIG. 4A is an elevation view of a front carrier of the frame of the treadmill;

[0012] FIG. 4B is an elevation view of a rear carrier of the frame of the treadmill;

[0013] FIG. 5 is a plan view of a platen of the treadmill; FIG. 6A is an elevation of a roller assembly end cap of the treadmill and FIG. 6B is an elevation of another end cap of another roller assembly;

[0014] FIG. 7A is a partial elevation of a frame of the treadmill in accordance with another embodiment;

[0015] FIG. 7B is an elevation of a gear box of the treadmill; and

[0016] FIG. 8 is a perspective view of a treadmill in accordance with yet another embodiment of the present invention.

[0017] Referring to FIG. 1, there is shown an exploded perspective view of an aquatic treadmill 10 incorporating features of the present invention. Although the present invention will be described with reference to the single embodiment shown in the drawings, it should be understood that the present invention can be embodied in many alternate forms of embodiments. In addition, any suitable size, shape or type of elements or materials could be used.

[0018] Still referring to FIGS. 1A-1B, the treadmill 10 generally comprises a frame 12, rollers 14, platen 18 and treadmill belt 16. The treadmill 10 also includes an outer casing 20 and handrail 22. The rollers 14 and platen 18 are mounted to the frame 12. The treadmill belt 16 is supported by the rollers 14 and platen 18 to provide the treadmill with walkway areas 24, 26 on both top and bottom of the treadmill 10. The casing 20, is also mounted to the frame 12 and has seating surfaces 28, 30 on opposite sides to allow the treadmill 10 to be seated with either top or bottom on the pool seating surface P. This allows a user to use either walkway area 24, 26 of the treadmill as desired. The handrail 22 is removably mounted to the frame 12, and may be mounted to extend from either the top or bottom of the treadmill. The walkway areas 24, 26 of the treadmill are inclined relative to the horizontal seating surface P on which the treadmill is seated (as well as the axis of symmetry X of the treadmill 10). To advantageously allow a user to remain planted on the belt when using either walkway area 24, 26 for underwater exercises as will be described in greater detail below.

[0019] FIGS. 2A-2D are respectively a side elevation view, a top plan view, a partial plan view, and a partial front end elevation view of the treadmill 10 with the casing sections removed for clarity. In this embodiment the frame 12 generally comprises side plate assemblies 32, 33 and tie members 34, 36. The side plate assemblies are seen best in FIGS. 3A-3C which respectively show an elevation, top plan view and partial plan view of the treadmill with features further removed for clarity. Side plate assemblies 32, 33 are similar except as otherwise indicated below and will be described specifically with respect to side plate assembly 32. Side plate assembly 32 generally includes wall section 38, front carrier 40 and rear carrier 42. The wall section 38 is seen best in FIGS. 3A, 3C. The wall section 38 in this embodiment may be a one piece member made of corrosion resistant sheet metal, such as for example 316L-series stainless steel. In alternate embodiments, the side wall of the frame may be made from any other suitable material including plastic or composite materials. As seen in FIG. 3A, the side wall section 38 has a generally tapered shape with generally circular shaped front and rear end sections 38F, 38R. The front end section has holes 44 formed therein to aid in elevation of air from the treadmill during submergence and for water drainage when raising the treadmill from water as will be described further below. The rear end section 38R has a slotted hole 46 substantially aligned with axis X. This slot 46 allows for floating movement of the rear roller relative to the frame as will be further described. Wall section 38 also has top and bottom flanges 38T, 38B protruding outwards from the center wall portion 38W of the section. Thus wall section 38 has a general channel cross-section formed by center wall 38W and top and bottom flanges 38T, 38B. In alternate embodiments, the wall section may have any other suitable cross-section. In other alternate embodiments, the wall section may be an assembly of sections. For example, the front end section (similar to section 38F) may be mechanically attached by fasteners or rivets, or by bonding to the rest of the wall section. The front end section 38F may be provided with a central bore 45 for mounting the front roller to the side wall section 38. U-shaped slots are formed into the center wall portion 38W of the wall section 38 as seen best in FIG. 3A. The opening of the U-shaped slots is in the top flange 38T or wall section 38. The embodiment in FIGS. 3A-3C is shown as having 14 U-shaped slots 52, though in alternate embodiments the number of slots may vary as desired. The top flange 38T has notches 49A-49C formed in its outer edge. Similar notches are formed into the outer edge of the bottom flange 38B. The notches 49A-49C in the top and bottom flanges are used for positioning and locking the front and rear carriers 40, 42 to the wall section 38. In alternate embodiments, more or fewer locating notches may be formed into the flanges of the wall section as desired. The center wall portion 38W may also include mounting holes 48, 50 for cross tubes which will be described further below.

[0020] Referring now to FIG. 4A, there is shown an elevation view of the front carrier 40. The front carrier 40 may also be a sheet metal member made from 314L stainless steel or other suitable material. The front carrier has a generally circular section 40C and a tab section 40T extending therefrom. The circular section 40C is generally similar in size and shape to the front end section 38F of the wall section 38. Holes 40H are formed into section 40C similar in shape to the holes 44 in front end section 38F. The carrier also has a center clearance hole 40S. The sheet metal of the front carrier is bent to provide inward flanges 40F1-40F3. As seen in FIG. 4A flanges 40F1 and 40F2 are located top and bottom of the circular section 40C. Flange 40F3 is located at the front. The flanges 40F1-40F3 have a width that generally complements the width of the outward flanges 38T, 38B of the wall section 38. The upper and lower flanges are generally inclined relative to axis or symmetry X. Fastener holes 40B are provided in each flange 40F1, 40F2 (four holes 40B are shown in the embodiment for example purposes) for mounting feet 28, 30 to the front carrier. The tab portion 40T has a generally tapered shape conforming to the corresponding area of wall section 38 where the tab portion 40T is mounted. Top portion 40T has locating detents 40L1, 40L2 along the upper and lower edges conforming to notches 49A in the flanges 38T, 38B or wall section 38 (see FIGS. 3A and, 4A). Fastener holes 40M (in this embodiment four holes 40M are shown for example purposes) are provided for mounting fasteners (not shown) used to fasten front carrier 40 to the wall section 38.

[0021] Referring now to FIG. 4B, there is shown an elevation view of the rear carrier 42. The rear carrier 42 may be a sheet metal member made from 314L stainless steel or other suitable material. The rear carrier has rear section 42R and a tab section 42T extending there from. The rear section 42R has a slotted hole 42S similar to slot 46 in the rear end portion 38R or wall section 38. The rear section 42R is provided with inward flanges 42F1-42F4. The flange width compliments that of flanges 38T, 38B of the wall section, thereby allowing the rear section 42R of the carrier 42 to be seated against the face of this rear end portion 38R of the wall section 38. Upper and lower flanges 42F1, 42F2 are symmetrically inclined with respect to axis or symmetry X. Fastener holes 42B are located in the flanges 42F1, 42F2 (three holes are shown in each flange for example purposes) allowing the feet 28, 30 to be fastened to the flanges of the rear carrier. Tab portion 42T of the rear carrier is sized to conform to the tapered space between flanges 38T, 38B in the corresponding area of wall section 38 where the rear carrier is mounted (see FIG. 3A). Tab portion 42T has locating detents 42L1, 42L2 along upper and lower edges conforming to notches 49B, 49C formed in the outer edge of flanges 38T, 38B or wall section 38. A mounting hole 42H may be provided in the tab portion 42T for inserting a cross member of the frame. The front and rear carriers 40, 42 may be attached to the wall section 38 by welding, brazing or otherwise bonding the respective flanges 40F1-40F3, 42F1-42F4 of the front and rear carriers to the corresponding faces of the front and rear portions 38F, 38R of this wall section. Positioning of the front and rear carriers 40, 42 on the wall section 38 prior to attachment is aided by the interface between locating detents 40L1-40L2 of the front carrier, and detents 42L1-42L2 of the rear carrier with the corresponding notches 49A, 49B, 49C in the flanges 38T, 38B (see FIG. 3A). If desired, the front carrier may be removably mounted to the wall section 38 with fasteners such as bolts or screws inserted through holes 40M. In this case spacers (not shown) may be placed between the center wall 38C and this section 40T of the front carrier to prevent undesired deflection during fastener torquing of the tab section 42T and center wall 38C. The front carrier 40 may be removably mounted to the wall section 38 in the case where the treadmill 10 is provided with a speed regulator as will be described further below.

[0022] As noted before, the frame 12 includes tie members that connect the side wall assemblies 32, 33 to each other and help to provide the frame with a substantially rigid box shape. In this embodiment the tie members are cross tubes 34, 36, though any other suitable type of tie member may be used. The cross tubes 34, 36 in this embodiment are cylindrical though they may have any suitable cross-section. The tubes 34, 36 are respectively inserted through holes 48, 50 in the center wall portion 38C of the wall assemblies (see. FIG. 3A). In addition, the rear cross tube 36 may extend through the hole 42H in the rear carrier 42 (see FIG. 4B). Cross tubes 34, 36 may be welded, brazed or bonded by any suitable means to the center wall portion 38C of the wall assemblies thereby securing the opposing wall assemblies 32, 33 to each other.

[0023] Additional rigidity may be provided to the frame 12 by platen 18. An elevation view of the platen 18 is shown in FIG. 5. Platen 18 in this embodiment is a flat member made of corrosion resistant sheet metal or plastic sheet. The platen may have a generally square or rectangular shape. The platen is sufficiently wide to extent at least to the outer edges of flanges 38B of the side wall assemblies 32, 33. As seen in FIG. 5, the platen has a row or fastening holes 18F along the outer edges 180. Similar holes (not shown) are drilled into the bottom flanges 38B of the wall assemblies. The length of the platen is sized to provide a suitable walkway area on the treadmill. Longitudinal locating slots 18S are formed into the platen. In this embodiment, there are two rows of locating slots 18S which are used for interlocking keel or stiffeners 50 (see FIG. 3A) to the platen 18 as will be further described. In alternate embodiments, the platen may have any suitable number or shape of locating features allowing stiffeners to be interlocked with the platen. As seen in FIG. 3A, when installed the platen 18 is disposed against the bottom surfaces of flange 38B of the side wall assemblies 32, 33 (see also FIG. 3B). Accordingly, the installed platen 18 is positioned by the tapered section of the side wall assemblies at an incline relative to the axis or symmetry X of the treadmill. The angle of inclination a (see FIG. 3A) may be established as desired up to 10 or more, though in the embodiment the angle a is depicted at about 7. As can be realized from FIG. 3A, it may be desirable to install the platen 18 to the frame 12 with the keel plates 50 previously mounted to the platen 18. Only one keel plate 50 is visible in FIG. 3A, though as noted before, the platen 18 has two rows of locating holes 18S for mounting keel plates to the platen. In alternate embodiments, any suitable number of keel plates may be used including only one keel plate positioned generally along the center line of the platen. As seen in FIG. 3A, keel plates 50 extend substantially to the length of platen 18. One edge 50B of the keel plates has locating detents 50D conforming to the size and location of locating slots 18S (see FIG. 5) in the platen. At the opposite edge 50T, the keel plates 50 have cutouts 50A, 50C for cross tubes 34, 36. Cutouts 50A 50C compliment the size and location of the corresponding cross tubes 34, 36 allowing the keel plates 50 to be seated against the cross tubes when the platen 18 with the keel plates 50 thereon is mounted to the frame 12. This significantly increases the stiffness of the platen 18 resulting in little deflection when walked on, the keel plates may be secured to the platen by spot welding, brazing or any other suitable attachment means. As noted before, the platen 18 and keel plate assembly may be mounted to the frame by riveting or otherwise fastening the platen 18 to the flanges 38B of the side wall assemblies 32, 33.

[0024] Referring now again to FIGS. 2A-2D, the rollers 14 generally comprises front roller assembly 52, rear roller assembly 54 and platform rollers assemblies 56. As seen in FIGS. 2A and 2B, the front roller assembly 52 is located at the front of the treadmill and the rear roller assembly 54 is at the rear of the treadmill. The front roller assembly 52, and rear roller assembly 54 provide the opposing supports on which the treadmill belt 16 travels. The platform roller assemblies 56 are disposed between the front and rear roller assemblies 52, 54 as shown in FIGS. 2A and 2B to provide one of the treadmill walkway areas 24. Referring also to FIG. 3B, the front roller assembly 52 generally comprises tube 52T and end caps 58. The tube 52T may be made of suitable plastic or composite materials with properties that will not degrade with long term immersion in chlorinated pool water. The tube may also be made of corrosion resistant metal or any other suitable material if desired. The diameter and wall thickness of the tube may also be as desired, though in this embodiment the tube has an outer diameter of about 8.05 inches and a wall thickness of about 0.065 inches for example purposes. The exterior surface of the tube 52T may be provided with suitable roughness (such as by ribbing or scarifying) if desired to provide improved contact with the treadmill belt 16. FIG. 6A shows an elevation view of an end cap 58. The end caps 58 at opposite ends of tube 52 are substantially the same. Each end cap 58 comprises outer ring 58R, hub 58H, and spokes 58S connecting the hub to the outer ring. The outer ring 58R may be sized to form an interference fit with tube 52T. The outer ring 58R has an outward radial flange 58F at one end as seen in FIG. 3B. The radial flange 58F acts as a stop when inserting the end cap 58 into tube 52. In addition, radial flange 58F extends sufficiently outwards so that it forms in combination with the radial flange 58F of the opposing end a guide channel 52G for the treadmill belt. The outer edge 58E of the radial flange 58F is radiused to remove sharp edges from the proximity of a user's feet when using the treadmill. As seen in FIG. 6A, the hub 58H or the front end cap 58 has a bore 580 for a bushing 59 (see FIG. 3B). In this embodiment, the bore 580 has a hexagonal shape, though in alternate embodiments the bore may have any suitable shape with locking facets to prevent the bushing from rotating inside the bore. Spokes 59S allow air to escape the roller assembly readily when the treadmill is being submerged, and allow water to drain readily when the treadmill is taken out of water. As seen in FIG. 2B, a shaft 60 is located inside the front roller assembly 52. Shaft 60 may be a cylindrical rod made of corrosion resistant metal or any other suitable material. The shaft 60 may be placed inside the roller through the bore 580 in the hub or the end cap. Bushings 59 may then be inserted into the respective bores of the end caps to axially secure the roller assembly 52 onto shaft 60. The bushings 59 allow the roller assembly to rotate freely on the shaft 60. Accordingly, the bushing 59 may be made from any suitable material such as for example Delrin with 12-14% PTFE. The front roller assembly is mounted onto frame 12 by inserting shaft 60 through mounting holes 40B (see FIGS. 3A-3B) in the front end sections of the side wall assemblies 32, 33. The end portions of the shaft 60 are sized to form an interference fit with the mounting bores 40B of the side wall assembly 32, 33 thereby fixing the shaft in the frame 12 of the treadmill. Spindle portions 60S of the shaft extend outwards from the side wall assemblies (see FIG. 2B) allowing accessories to be mounted to the treadmill as will be described further below.

[0025] The rear roller assembly 54 is generally similar to the front roller assembly 52 comprising tube 54T and end caps 62 at opposite ends of the tube 54T. Tube 54T is smaller in diameter than the tube 52T of the front roller assembly. The size difference between the front roller tube 52T and the rear roller tube is established as desired to provide the treadmill belt 16 with the desired incline angle a (see FIG. 2A) in walkway area 24 of the treadmill. In this embodiment, the rear roller tube has an outer diameter of about 4.06 inches, resulting in an incline angle a of about 70 as noted before. End caps 62, an elevation view of which is shown in FIG. 6B, have ring section 62R, hub 62H and spokes 62S. The ring section 62R is flanged with outward radial flange 62F. The outer edge 62E of the radial flange 62F is rounded to remove sharp edges from the user's feet. The ring section 62R may have outer raised ribs or gussets 62G (see FIG. 3B) to increase the interference between the ring section and tube 54T when the end caps 62 are inserted into the tube (similar ribs may be provided on the ring sections 58R of the front end caps). The hub 62H may have a bore 620 shaped to rotationally fix a bushing 63 therein. In this embodiment the bore 620 is hexagonal as is bushing 63. Bushing 63 is generally similar to bushing 59 described before. As seen in FIG. 3B, when the end caps 62 are installed in tube 54T, the radial flanges 62F of the opposing end caps 62 form a belt guide channel 54G at the rear roller assembly 54. A shaft 66 is located inside the roller tube 54T of the rear roller assembly as shown in FIG. 2B. The shaft 66 is generally similar to shaft 60 described before. Shaft 60 is positioned inside the roller assembly 54 by bushings 63 located in the end caps. The bushings 63 allow the roller assembly to rotate freely about the shaft 66. The end portions 66S of shaft 66 are placed in slotted holes 46 and 42S respectively of the wall section 38 and rear carrier 42 of the frame side wall sections 32, 33 as shown in FIGS. 2A and 2C. The end portions 66S may be provided with flattened surfaces conforming to the flat edges of slots 46, 42S or may have a linear bushing (not shown) mounted thereon with flat sliding surfaces. This prevents the shaft from rotating within slots 46, 42S while being allowed to slide linearly with in the slot. As seen best in FIGS. 2A and 2C springs 70 (only one spring is visible in FIGS. 2A and 2C) are disposed against the end portions 66S or shaft 66 to bias the rear roller assembly 54 toward the rear of the treadmill. This maintains a preload tension on the treadmill belt 16 in order to take up slack during use. In this embodiment, the spring 70 is a coil spring which is biased between the rear cross tube 36 of frame 12 and the end portion 66S of the shaft 66.

[0026] Referring still to FIG. 2B, in this embodiment there are fourteen platform rollers 56. In alternate embodiments there may be any desired number of platform rollers. All platform rollers 56 are substantially the same, and will be described below with reference to an exemplary roller. Roller 56 generally comprises tube 56T, and end caps 72 located at opposite ends of the tube. Tube 56T may have any desired diameter to provide an appropriate walkway area. In this embodiment, tube 56T has an outer diameter of about 1.5 inches, though as noted before any suitable size tube may be used. The tube material may be the same as the material for the tubes 52T, 54T of the front and rear roller assemblies noted before. The tube 56T is shown more clearly in FIGS. 3A-3B where the end caps 72 have been removed for clarity. The end caps 72 are substantially the same and similar to the end caps 58, 62 of the front and rear roller assemblies. Thus, the platform roller end caps 72 have an outer ring section 72R, a hub 72H and spokes 72S extending in between. The outer ring section 72R is sized to form an interference fit with tube 56T. External ribs or gussets similar to ribs 62G (see FIG. 3B) on the front and rear end caps 58, 62 may be located on the ring section 72R to enhance the interference between end cap 72 and tube 56T. The hub 72H has a bore for pin 80 which is fixedly mounted therein. The pin 80 rotatably secure each platform roller to bushings 82 on the frame 12 as shown in FIGS. 2A and 2C. The spokes 72S in the end cap 72 allow the end cap to have large openings in a manner similar to end caps 58, 62 or the front and rear roller assemblies to provide for ready evacuation of air from the roller 56 during submergence and for water drainage from the platform roller when the treadmill is taken out of water. The bushings 82 holding the platform rollers 56 in the frame 12 are best seen in FIGS. 2A and 2C. The bushings 82 similar to the other bushings in this embodiment are made of Delrin with 12-14% PTFE though any suitable material may be used. In this embodiment bushings 82 are configured in a twin bushing molding with two side by side bushings 82A, 82B as seen in FIG. 2C. The twin bushing configuration facilitates installation of the bushings on the frame 12, though in alternate embodiments each individual bushing may be individually mounted to the frame. Bushings 82A, 82B are sized to be admitted into U-shaped holes 51 in the upper edge of wall section 38 (see FIGS. 3A and 3C). The bushings 82A, 82B are inserted into holes 51 through the opening in the flange 38T. The retaining member 82R of the twin bushing molding tying the bushing 82A, 82B is positioned on the inside surface of wall section 38C thereby capturing the twin bushing in the wall section 38C. As seen in FIG. 2A, the twin bushings 82, located by U-shaped holes 51, are inclined at angle a relative to the axis of symmetry X of the treadmill 10. Accordingly, when mounted to the frame, the platform rollers 56 are arranged sequentially along the inclination of the twin bushings. Thus, the treadmill belt 16 resting on the platform rollers 56 in the walkway area 24 formed by platform rollers 56, is also inclined at angle a relative to axis X.

[0027] As seen in FIGS. 2A and 2B, treadmill belt 16 is mounted over the front and rear roller assemblies 52, 54. Platform rollers 56 support the belt in walkway areas 24, and platen 18 supports the belt in walkway area 26. The rollers 52, 54, 56 as well as the support surface of the platen 18 allow the belt 16 to rotate freely in either clockwise or counter clockwise directions. As can be realized the treadmill may be positioned with the platen side down (as shown in FIG. 2A) to allow a user to walk on walkway area 24, or may be positioned with the platform roller side down (inverted from the position shown in FIG. 2A) to allow the user to walk on walkway area 26. As can be realized belt rotation when the user is walking or running on walkway area 26 is opposite to belt rotation when walking/running on walkway area 24. The guide channels 52G, 54G formed by the radial flanges of the front and rear roller assemblies maintain the position of the belt 16 when moving, preventing it from drifting laterally. The axial bias on the rear roller assembly 54 from springs 70 help eliminate any slack in the belt during use.

[0028] Installation and removal of the belt from the treadmill may be facilitated by removing the front roller assembly 52 from the frame 12. Accordingly, in another embodiment, one of the side wall assemblies 32, 33 may have a wall section 38 with a removable front end portion 102 as shown in FIG. 7A. Wall section 38 in this embodiment is substantially similar to wall section 38 described before and shown in FIGS. 3A-3C except as otherwise noted. Similar features are similarly numbered. In this embodiment, the wall section 38 has a front edge 38F located substantially proximate the front end of flanges 38T, 38B. The front end section 102 may be mechanically connected with suitable fasteners (not shown) inserted through fastener holes 102M (see FIG. 7A) to the center portion 38C of the wall section 38. The end section 102 has a bore 40B for shaft 60 (see FIG. 2B). The fastener holes 102M are aligned with the fastener holes 40M in the front carrier 40 (see FIG. 4A) allowing section 102 and carrier 40 to be mounted as a unit, using the same fasteners, to the wall section 38.

[0029] If desired, a speed regulator 110 may be optionally connected to the front roller assembly 52. In this embodiment, the speed regulator generally comprises a momentum or fly wheel 112 and a gear box 114 linking the momentum wheel 112 to the front roller assembly 52 and hence to the belt 16. An elevation view of the gear box assembly 112 is shown in FIG. 7B. The gear box frame may advantageously be formed by the front carrier 40 and removable front end section 102 described before. As seen in FIG. 7A, a hole 104 may be formed in end section 102 to allow installation of a shouldered through bushing 122. Through bushing 122 has a hole for mounting a pinion shaft 124 there through. The pinion shaft may have two gears 116, 118 fixedly mounted thereto. Pinion gear 116 is mounted at an inner end of the shaft, and step up gear 118 is mounted at the outer end of the shaft. The pinion gear 116 is positioned to engage a drive gear 114 mounted to the front roller assembly 62. The step up gear 118 is positioned to engage idler gear 120 on the momentum wheel. The gears 114, 116, 118 120 of the gear box drive train are sized to provide a 4:1 step up ratio between the front roller 52 and momentum wheel. The momentum wheel 112 and idler gear 120 may be formed as an integral unit or may be connected mechanically. The momentum wheel 112 and idler gear 120 are seated on the spindle 60S or shaft 60 (see FIG. 2B) and are free to rotate about spindle 60S. The momentum wheel 112 may be formed from any suitable material to provide a desired mass moment or inertia to the wheel. The momentum wheel 112 may, further include fan blades 112, angled with respect to the axis or shaft 60, or aligned with respect to the axie axis, which provide a dynamic resistance to movement of the front roller assembly. As noted before, the speed regulator 110 may be removably mounted as a unit to the frame 112 and front roller assembly. Prior to mounting of the speed regulator 110 to the frame, the drive gear 114 may be affixed to the end cap 58 of front roller assembly 52 as shown in FIG. 2D.

[0030] The speed regulator may further include a radial impeller 130 if desired, which may be optionally coupled to the fly wheel 112 as shown in FIG. 2B. The radial impeller 130 is sized to be housed within the casing cover 20R mounted on the frame as shown in FIG. 3B. Referring also to FIG. 1A, the casing 20 of the treadmill include to opposing covers 20L, 20R. Each cover 20L, 20R is a substantially hollow shell, made of suitable composite material, sized to cover the side wall section 32, 33 of the treadmill frame. The front and rear ends of the covers 20L, 2OR are rounded so that when viewed from the side, the front and rear roller assemblies are hidden behind the cover profile. The front end of each cover has a generally annular or torroidal shaped section 20V which defines a center opening 20D and an inner annular channel 20C around the opening. Impeller 130 is positioned proximate torroid section 20V so that the section substantially forms a volute around the rim of the impeller 130. The impeller 130 may be oriented to draw or suction water through the tube 52T of the front roller assembly. The position of the impeller 130 proximate the end cap of the roller assembly 52 allows the flow through the tube to be channeled to the impeller. The roller tube 52T, and gear box assembly 112 form a conduit 132 to the impeller 130. The water is directed outward from the impeller 130 into section 20C of the cover 20R and out through a suitable exhaust port (not shown) in the cover. A hair screen 21D may be mounted over the hole 200 in the covers 20R, 20C (see FIG. 1A).

[0031] The covers 20R, 20L has openings to allow feet 28, 30 to be mounted to Frame 12. Feet 28, 30 are shown best in FIG. 2A. Feet 2B are mounted to one side of the frame 12, and feet 30 are mounted on the opposite side. The feet of the unit are non-skid, of significant surface area, and generally elliptical to prevent peel. They are externally removable and easily replaceable with feet of different heights to permit additional options with respect to inclining the unit.

[0032] Referring now to FIGS. 1A-1B, 2A and 2D, the handrail 22 generally comprises rail tube 22T, rail Stop 22S, padding 22P and knob 22K. The rail tube may be a one piece member made from any suitable corrosion resistant tubing. Rail stop 22S is a sleeve sized to be placed over tube 22T. The rail stop has a tapered section allowing the rail stop to be self centering when positioned into the handrail receiver 300 in the frame 12 to be described further below. The rail stop 22S may be fixed to tube 22T by mechanical fastening or bonding. The knob 22K is mounted to the bottom of the handrail 22. The knob 22K prevents inadvertent removal of the handrail from the receiver 300. The knob 22K is mechanically fastened to the rail tube 22T with a screw (not shown). An insert 22I is fixed inside the tube 22T as shown in FIG. 2A to allow engagement of the knob fastening screw. The padding 22P is positioned over the grip portion of the handrail. The outer surface of the padding on the grip is provided with a suitable reflective surface to provide a visual indication at the water surface S of the handrail. The frame 12 includes handrail receiver 300. The handrail receiver includes similar but opposite sections 300L, 300R on the side wall sections of the frame. One exemplary section 300R will be described. Section 300R of the receiver includes a receiving tube 304 supported from the side wall section 38 by support brackets 302 as shown in FIGS. 2C and 2D. The receiving tube 304 is open at both ends so that the handrail may be mounted on either side of the treadmill. The handrail rail stop 22S cooperates with the opening of the receiver 304 to self center the handrail in the receiver when inserted. After insertion into the receiver 300, the knob 22K may be fastened to the bottom of the handrail locking the handrail in the receiver as shown in FIG. 2A.

[0033] Referring now to FIG. 8, there is shown a perspective view of the treadmill in accordance with another embodiment. Treadmill 10A is substantially similar to the treadmill of the previously described embodiments. Treadmill 10A is also provided with a pair of articulated swim poles 400. Each pole 400 comprises a connection section 402, vertical section 404, intermediate link, and upper section 408. Upper section 408 may include a rotatable hand grip 410. Link 406 pivotally connects section 408 to vertical section 404. Section 402 allows the vertical section to rotate relative to the frame in the direction indicated by arrow R in FIG. 8. Paddle 412, or other assistance surfaces may be mounted to this section 404. The paddle 412 may be raised or lowered, and may be rotated to coincide with the direction of motion of the swim pole 400. The swim pole 400 is an aquatic equivalent to a ski pole in that one handgrip 410 is in each of the user's hands and the user establishes an alternating cadence with these while walking on the treadmill 10A. The alternating action of the poles may be linked to the walkway belt mechanically, or as in the current embodiment the action of the poles is independent of the movement of the belt. The user is free to move his arms from the typically head high upper portion of the swing to the behind the buttocks arc. The handgrips 410 are rotatably attached to the upper end of the first section of the swim pole. The lower end of the upper section of the swim pole is hinged to the lower section of the swim pole. This lower section always remains below water. In effect, the upper section of the swim pole is used to drive the lower section (containing the paddle) back and forth through the water. The paddle 412 on the lower section 404 can be removed (limiting the resistance to that of the pole alone), fixed (such that the resistance is bidirectional), hinged (such that the resistance is unidirectional), sliding (such that it can be lowered, thereby reducing the effective resistance via improving the mechanical advantage the user has) or linked (such that the motion can be varied to advantage via a linkage).

[0034] The upper section 408 of the swim pole can be folded and snapped to the lower section 404 of the swim pole such that the envelope of the product, when not in use, is not significantly increased with this feature. The lower sections of the swim poles contain a stop provision such that if the user stores them or drops them they do not fall to the bottom of the pool.

[0035] The treadmill 10, 10A of the present invention provides significant advantages over conventional treadmills. For example, the build-in incline of the unit, created by the side similar roller tube sizes, is a key advantage in aquatic use. It is actually more difficult to walk on horizontal beltway in the water, as it causes one to hunch over to combat the effects of buoyancy on the body. The hollow rollers permit their use as tubes. This affords the advantages of more neutral buoyancy (as the tubes fill with water, damping (as the water must be churned in use), and conduiting, (as in the case of now permitting the impeller to fall within the confines of the unit's enclosure the water enters on one side of the unit and exhausts on the other). The external shape of the unit is completely compatible with vinyl liners/sand bottom pools, which would otherwise be damaged by a product with sharp outside corners. This is particularly true during placement and removal of the unit from the pool. This advantage extends to the user, in that contact with bare feet without injury is probable. The unit's shape is longitudinally symmetrical (in the plane of the axles) but more significantly invertible, allowing the roller supported beltway configuration as well as the platen supported mode. The roller supported beltway is relatively frictionless. In this model, the vast majority of the effort (on the part of the user) is expended in overcoming the resistance of the water and is bi-directional in nature. When the platen mode is elected, the exercise more closely resembles the primarily forward thrust nature of a self-powered land based unit.

[0036] It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.