SWIM-EXERCISE APPARATUS AND WATER PROPULSION SYSTEM THEREFOR

Abstract

A swim-exercise apparatus includes a water containment vessel having a first area defining a swimming/bathing compartment for enabling a user to swim-in-place within the apparatus and a water propulsion system for generating a directed flow of water in the swimming/bathing compartment of the water containment vessel. The water propulsion system includes a water pump having a scroll-shaped blower housing and a centrifugal blower impeller rotatively disposed within the blower housing. The centrifugal blower impeller includes a plurality of arcuate-shaped blades positioned about a central axis of the centrifugal blower impeller, each of the blades having a convex-shaped water pressure surface. The water propulsion system further includes a motor for rotatively driving the centrifugal blower impeller.

Description

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 63/615,241, filed on Dec. 27, 2023, the entire disclosure of which is incorporated herein by reference.

FIELD

The present disclosure relates to swim-exercise apparatuses, and more specifically, to a swim-exercise apparatus having a blower-based water propulsion system.

BACKGROUND

It is well known that exercise improves health and increases longevity. One form of exercise is swimming. Swimming is desirable because it is a low impact type of exercise that provides cardiovascular benefits.

Recently, swim-in-place systems, such as swim spas, have become available. A swim spa enables a swimmer to swim without the need for a pool. A typical swim spa includes a water propulsion assembly that includes a pump comprising a motor driven propeller, and one or more water jets directed toward the swimmer. The pump of the water propulsion system propels water against the swimmer so that the swimmer can swim in a generally stationary position, against the force of the water, thereby simulating swimming forward in the water of the swim spa.

An improved water propulsion system and swim-exercise apparatus are needed that enhances the user's experience.

SUMMARY

Disclosed herein is a water propulsion system for generating a directed flow of water in a swim-exercise apparatus. In various embodiments, the water propulsion system comprises a water pump including a scroll-shaped blower housing and a centrifugal blower impeller rotatively disposed within the blower housing, wherein the centrifugal blower impeller includes a plurality of arcuate-shaped blades positioned about a central axis of the centrifugal blower impeller, each of the blades having a convex-shaped water pressure surface. The water propulsion system further comprises a motor for rotatively driving the centrifugal blower impeller.

In some embodiments, the water propulsion system further comprises a pump impeller drive arrangement including a first pulley, a driveshaft, and a drive belt, wherein a first portion of the driveshaft is coupled to the first pulley and a second portion of the driveshaft is coupled to centrifugal blower impeller, wherein the electric motor includes a second pulley, and wherein the drive belt rotatively couples the second pulley of the electric motor to the first pulley coupled to the first portion of the driveshaft of the pump impeller drive arrangement.

In some embodiments of the water propulsion system, the blower housing has a scroll-shape and includes a central, axial water inlet and a tangential water discharge outlet.

In some embodiments of the water propulsion system, a distance between an inner surface of the blower housing and an outer periphery of the centrifugal blower impeller increases moving in a direction toward the water discharged outlet of the blower housing.

In some embodiments of the water propulsion system, the centrifugal blower impeller further includes a ring-shaped outer member and a disc-shaped outer member, and wherein the plurality of arcuate-shaped blades extend between the outer ring-shaped member and the disc-shaped outer member.

In some embodiments of the water propulsion system, the centrifugal blower impeller further includes first and second ring-shaped outer members and a disc-shaped inner member positioned between the first and second ring-shaped outer members, and wherein the plurality of arcuate-shaped blades includes a first blade element extending between the first ring-shaped outer member and the disc-shaped inner member and a second blade element extending between the second ring-shaped outer member and the disc-shaped inner member.

Further disclosed herein is a swim-exercise apparatus. In various embodiments the swim-exercise apparatus comprises a water containment vessel having a first area defining a swimming/bathing compartment for enabling a user to swim-in-place within the apparatus and a water propulsion system for generating a directed flow of water in the swimming/bathing compartment of the water containment vessel. In various embodiments, the water propulsion system comprises a water pump including a scroll-shaped blower housing and a centrifugal blower impeller rotatively disposed within the blower housing, wherein the centrifugal blower impeller includes a plurality of arcuate-shaped blades positioned about a central axis of the centrifugal blower impeller, each of the blades having a convex-shaped water pressure surface. The water propulsion system further comprises a motor for rotatively driving the centrifugal blower impeller.

In some embodiments of the swim-exercise apparatus, the water pump is disposed in a pump compartment defined in a second area of the water containment vessel.

In some embodiments of the swim-exercise apparatus, the pump compartment is formed by at least one wall of the water containment vessel and a false wall that separates the pump compartment from the swimming/bathing compartment of the water containment vessel, wherein the false wall includes a water outlet opening and at least one water inlet opening, and wherein the water outlet opening is aligned with a water discharged outlet of the blower housing of the water pump.

In some embodiments, the swim-exercise apparatus, further comprises a top deck for covering the pump compartment.

In some embodiments of the swim-exercise apparatus, the top deck is a tray-shaped member having a ribbed cover wall that slopes downward toward the swimming/bathing compartment of the water containment vessel.

In some embodiments of the swim-exercise apparatus, the at least one wall of the water containment vessel is fluted to increase the structural integrity of the pump compartment.

In some embodiments, the swim-exercise apparatus further comprises a screen-like element is attached to a back side of the false wall to cover the at least one water inlet opening.

In some embodiments, the swim-exercise apparatus further comprises a grate disposed in the water outlet opening of the false wall, the grate for straightening the turbulent flow of water discharged from the water discharge outlet of the blower housing, thereby increasing a laminar flow of water directed at the user in the swimming/bathing compartment of the water containment vessel.

In some embodiments, the swim-exercise apparatus further comprises a grate angle-adjustment mechanism that includes a knob disposed on a front side of the false wall for enabling the user to adjust the angle of the grate relative to the water discharge outlet of the blower housing to change a direction of water discharged through water outlet of the blower housing.

In some embodiments, the swim-exercise apparatus further comprises a pump impeller drive arrangement including a first pulley, a driveshaft, and a drive belt, wherein a first portion of the driveshaft is coupled to the first pulley and a second portion of the driveshaft is coupled to centrifugal blower impeller, wherein the electric motor includes a second pulley, and wherein the drive belt rotatively couples the second pulley of the electric motor to the first pulley coupled to the first portion of the driveshaft of the pump impeller drive arrangement.

In some embodiments of the swim-exercise apparatus, the first pulley, the first portion of the driveshaft, the drivebelt, and the electric motor are disposed outside of the water containment vessel.

In some embodiments, the swim-exercise apparatus further comprises a frame for supporting the water containment vessel, and a cabinet to enclose the frame, the first pulley, the first portion of the driveshaft, the drivebelt, and the electric motor.

In some embodiments of the swim-exercise apparatus, the blower housing has a scroll-shape and includes a central, axial water inlet and a tangential water discharge outlet.

In some embodiments of the swim-exercise apparatus, a distance between an inner surface of the blower housing and an outer periphery of the centrifugal blower impeller increases moving in a direction toward the water discharged outlet of the blower housing.

In some embodiments of the swim-exercise apparatus, the centrifugal blower impeller further includes a ring-shaped outer member and a disc-shaped outer member, and wherein the plurality of arcuate-shaped blades extend between the outer ring-shaped member and the disc-shaped outer member.

In some embodiments of the swim-exercise apparatus, the centrifugal blower impeller further includes first and second ring-shaped outer members and a disc-shaped inner member positioned between the first and second ring-shaped outer members, and wherein the plurality of arcuate-shaped blades includes a first blade element extending between the first ring-shaped outer member and the disc-shaped inner member and a second blade element extending between the second ring-shaped outer member and the disc-shaped inner member.

In some embodiments of the swim-exercise apparatus, the swim-exercise apparatus is a swim spa and the water containment vessel is a spa shell.

Still further disclosed herein is a method for propelling water against a swimmer in a swim-exercise apparatus so that the swimmer can swim in a generally stationary position, against the force of the water, thereby simulating swimming forward in the water of the swim-exercise apparatus. The method comprises providing a water propulsion system in a section of a water containment vessel of the swim-exercise apparatus, and generating, with the water propulsion system, a directed flow of water in a swimming/bathing compartment of the water containment vessel of the swim-exercise apparatus. In various embodiments, the water propulsion system comprises a water pump including a scroll-shaped blower housing and a centrifugal blower impeller rotatively disposed within the blower housing, wherein the centrifugal blower impeller includes a plurality of arcuate-shaped blades positioned about a central axis of the centrifugal blower impeller, each of the blades having a convex-shaped water pressure surface. The water propulsion system further comprises a motor for rotatively driving the centrifugal blower impeller.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1A is a perspective view of an illustrative embodiment of a swim-exercise apparatus according to the present disclosure.

FIG. 1B is a perspective view of an illustrative embodiment of a water propulsion system according to the present invention.

FIG. 2A is a front perspective view of an illustrative embodiment of a pump compartment configured in an area of a containment vessel of the swim-exercise apparatus, according to the present invention.

FIG. 2B is a side perspective view of the pump compartment of FIG. 2A shown mounted on an illustrative embodiment of a section of a frame that supports the containment vessel.

FIG. 2C is a front perspective view of an interior of the pump compartment of FIG. 2A.

FIG. 3A is a front perspective view of an illustrative embodiment of a false wall of the pump compartment of FIGS. 2A-2C.

FIG. 3B is a rear perspective view of the false wall of FIG. 3A.

FIG. 3C is a side elevation of the false wall of FIG. 3A and of an illustrative embodiment of a side of a blower-type water pump of the water propulsion system, illustrating the position of the water pump to a rear side of the false wall.

FIG. 3D is a top perspective view of a portion of the pump compartment of FIGS. 2A-2C, which illustrates how the false wall is positioned relative to a side wall of a section of the water containment vessel defining the pump compartment side wall.

FIG. 4A is a top perspective view of an illustrative embodiment of a top deck, which is used to cover the pump compartment.

FIG. 4B is a side sectional perspective view of the top deck mounted of FIG. 4A mounted on the pump compartment of FIGS. 2A-2C.

FIG. 4C is a top sectional perspective view of the top deck of FIG. 4A mounted on the pump compartment of FIGS. 2A-2C.

FIG. 5A is a sectional perspective view of an illustrative embodiment of a blower-type water pump and a pump impeller drive arrangement.

FIG. 5B is a sectional perspective view of the blower-type water pump of FIG. 5A.

FIG. 5C is a sectional view of a first side of the blower-type water pump of FIGS. 5A-5B.

FIG. 5D is a sectional view of a second side of the blower-type water pump of FIGS. 5A-5B.

FIG. 5E is a sectional front view of the blower-type water pump of FIGS. 5A-5D.

FIG. 6 is an enlarged view of FIG. 5C.

FIG. 7A is a perspective view of the centrifugal blower impeller of the blower-type water pump of FIGS. 5A-5E.

FIG. 7B is a side view of a first side of the centrifugal blower impeller of FIG. 7A.

FIG. 7C is a side view of a second side of the centrifugal blower impeller of FIG. 7A.

FIG. 7D is an end view of the centrifugal blower impeller of FIG. 7A.

FIG. 7E is an enlarged view of a section of the centrifugal blower impeller of FIG. 7A, which depicts blade elements of the centrifugal blower impeller.

FIG. 7F is an enlarged view of FIG. 7D.

FIG. 7H is enlarged view of a section of the centrifugal blower impeller of FIG. 7B depicting an attack angle of a blade element of the centrifugal blower impeller.

FIG. 7G is a sectional view through line 7G-7G of FIG. 7F.

FIG. 8A is a front perspective view of an illustrative embodiment of a grate frame for removably holding a grate according to the present invention.

FIG. 8B is a rear perspective view of the grate frame of FIG. 8A.

FIG. 8C is a perspective view of a hinge for hingedly mounting the grate frame within a duct-shaped water outlet opening of the false wall of FIGS. 3A-3D.

FIG. 8D is a perspective view of an illustrative embodiment of a grate according to the present invention.

FIGS. 9A and 9C are front side perspective views of an illustrative embodiment of a grate angle-adjustment mechanism according to the present invention wherein FIG. 9A depicts a grate angled by the grate angle-adjustment mechanism at 0 degrees and wherein FIG. 9C depicts a grate angled by the grate angle-adjustment mechanism at 20 degrees.

FIG. 9B is a rear side perspective view of the grate angle-adjustment mechanism of FIG. 9A.

DETAILED DESCRIPTION

It should be understood that the phraseology and terminology used below for the purpose of description and should not be regarded as limiting. The use herein of the terms “comprising,” “including,” “having,” “containing,” and variations thereof are meant to encompass the structures and features recited thereafter and equivalents thereof as well as additional structures and features. Unless specified or limited otherwise, the terms “attached,” “mounted,” “affixed,” “connected,” “supported,” “coupled,” and variations thereof are used broadly and encompass both direct and indirect forms of the same.

FIG. 1A depicts an illustrative embodiment of a swim-exercise apparatus 10 according to the present disclosure. The swim-exercise apparatus comprises a water containment vessel 20 (hereinafter “spa shell”), which is configured to enable a swimmer to swim-in-place within the spa shell 20 of the apparatus 10. It is to be understood that the term “swim-exercise apparatus,” as used herein, refers to swim spas, therapeutic pools, fitness pools and any other type of water-based swim-exercise apparatus. As illustrated in FIG. 2B, the spa shell is conventionally supported by a frame 22, and a spa cabinet 24 is conventionally utilized to enclose the frame 22 and other components of the apparatus 10 including a spa control pack (not shown).

Referring still to FIG. 1A, the spa shell 20 includes a first end wall 20-1, a second end wall 20-2 (FIG. 2C) opposite the first end wall 20-1, opposing first and second sidewalls 20-3, 20-4 and a bottom wall 20-5. In various embodiments, the spa shell 20 (e.g., FIG. 1A) is configured to accommodate the body of a swimmer while in a generally elongated position and can be formed in different shapes and dimensions, and is typically a component of a swim spa. The water to be contained in the spa shell 20 can be unheated and/or heated via skimmers and suctions (not shown) that lead the plumbing to the spa control pack and a heater for temperature adjustment and monitoring of the spa.

Referring to FIG. 1B, the swim-exercise apparatus 10 further comprises a water propulsion system 100, which is operative for generating a directed flow of water in the spa shell 20. The water propulsion system 100 comprises a blower-type water pump 110 (water pump 110), a pump impeller drive arrangement 120 (impeller drive 120), and an electric motor 130 that rotatively drives a pulley 122 of the impeller drive 120 via a drive belt 140, which rotatively couples a pulley 132 of the electric motor 130 to the pulley 122 of the impeller drive 120.

Referring again to FIG. 1A and FIGS. 2A-2C, the apparatus 10 includes a spa shell false wall insert 30 (false wall 30) mounted within the spa shell 20, which divides the spa shell 20 into a pump compartment 40 that houses the water pump 110 (FIG. 2C), and a larger swimming/bathing compartment 60 (FIG. 1A). The pump compartment 40 is therefore defined by the second end wall 20-2 of the spa shell 20, portions 40-1, 40-2 of the spa shell sidewalls 20-3, 20-4, and a portion 40-3 of the spa shell bottom wall 20-5. A top deck 50 is provided for covering the pump compartment 40. As shown in FIG. 2C, the second end wall 20-2 of the spa shell 20, which forms a back wall of the pump compartment 40, has a planar central wall section 42-C surrounded on each side by a fluted wall section 42-F. In addition, the first and second pump compartment sidewalls 40-1 and 40-2 are formed with fluted wall sections 44-F. The fluted wall sections 42-F, 44-F of pump compartment 40 increase the structural integrity of the pump compartment 40 to prevent buckling during operation of the water propulsion system 100.

As illustrated in FIG. 2C, the water pump 110 of the water propulsion system 100 is fixedly mounted to the inner surface of the planar central wall section 42-C of the second wall 20-2 of the spa shell 20, which forms the back wall of the pump compartment 40, with a pair mounting brackets 112-BK (only one is visible).

Referring now to FIG. 5A, the impeller drive 122 further includes a driveshaft 124 having a first end 124-1 coupled to the pulley 122 of the impeller drive 120 and a second end 124-2 extending through a centrifugal blower impeller 114 of the water pump 110. A section 124-3 of the driveshaft 124 adjacent the second end 124-2 thereof, is coupled to the centrifugal blower impeller 114, to rotatively drive the blower impeller 114 of the water pump 110 when the electric motor 130 is activated. When driven by the electric motor 130 (FIG. 1B), the water pump 110 generates a directed flow of water, generally along the direction shown by arrow 12 in the spa shell (FIG. 1A). In use, the electric motor driven water pump 110 of the propulsion system 100 propels water against the swimmer in the spa shell 20 so that the swimmer can swim in a substantially stationary position against the force of the water.

As illustrated in FIG. 5A, the impeller drive 120 further comprises a through-wall hub 126 having a conventional bearing and seal arrangement, which rotatively mounts the pulley 122 of the impeller drive 120 to the outer surface of the respective pump compartment sidewall (e.g., 40-1) of the pump compartment 40 (formed by spa shell sidewall 20-3) so that the pulley 122 of the impeller drive 120 is external to the spa shell 20 within the spa cabinet 24. The driveshaft 124 extends from the pulley 122 of the impeller drive 120 through an opening (not shown) in the pump compartment sidewall 40-1. The through-wall hub 126 is conventionally configured to prevent water contained in the pump compartment 40 from leaking out from the pump compartment through the through-wall hub 126. As illustrated in FIG. 2B, the electric motor 130, which drives the water pump 110, is mounted external to the spa shell 20, within the spa cabinet 24 (FIG. 1A) and fixedly attached to the frame 22 of the apparatus 10.

In some embodiments, the electric motor 130 (FIG. 1B) comprises a 7.5 horsepower electric motor. In other embodiments, the electric motor 130 can comprise an electric motor with 5 horsepower or less, however, such an electric motor will lower the flow or speed of the swim current generated by the propulsion system 100. In still other embodiments, the electric motor 130 can comprise an electric motor with more than 7.5 horsepower, which will generate more speed but at a reduced efficiency. It has been determined that increasing the speed of the swim current increases the load in an almost exponential factor as can be seen in the below chart, and doing so only provides minimal gains in performance.

In some embodiments, the electric motor 130 is controlled by a variable frequency drive (not shown), which allows the speed of the electric motor 130 to be varied to fine tune the speed of the swim current generated for the swimmer.

Referring again to FIG. 1B, the diameter of the pulley 132 of the electric motor 130 and the diameter of the pulley 122 of the impeller drive 120 are sized to reduce the speed of the blower impeller 114 while keeping the ideal operational speed of the electric motor 130 at about 60 Hz. This allows the efficiency curve of the electric motor 130 to be maximized. In one non-limiting embodiment, the pulley 122 of the impeller drive 120 comprises a 19.00 inch diameter pulley and the pulley 132 of the electric motor comprises 4.50 inch diameter pulley. This provides a pulley 122 to pulley 132 diameter ratio of approximately 4:1.2. Other pulley 122 to pulley 132 diameter ratios are contemplated in other embodiments.

As illustrated collectively in FIGS. 2A, 2B, and 3A-3C, the spa shell false wall 30 has a front side 30-F and a back side 30-B and is formed with a plurality of gentle ridges 30-R that protrude out from the front side 30-F of the false wall 30. The false wall 30 includes a pair of lateral mounting flanges 30-LF and a top flange 30-TF that depends toward the back side 30-B of the false wall 30. The false wall 30 further includes a duct-shaped water outlet opening 32 and a plurality of water inlet openings 34. The water outlet opening 32 is located at a side-to-side center of the false wall 30 at a height that is below the water level of the swimming/bathing compartment and which allows water discharged therethrough to be directed toward a swimmer within swimming/bathing compartment 60 (FIG. 1A). The duct-like water outlet opening 32 is aligned and engaged with a tangential water discharge outlet 112-O of a housing 112 of the water pump 110 (FIG. 3C). Half of the water inlet openings 34 are positioned on a first lateral side of water outlet opening 32 and the other half of the water inlet openings 34 are positioned on a second lateral side of water outlet opening 32. The total cross-sectional area of the water inlet openings 34 is selected to assure adequate water flow into the pump compartment 40 to avoid pump cavitation. Disposed within the water outlet opening 32 is an angle-adjustable grate 118, which can be adjusted to direct the water upwardly as it is discharged through water outlet opening 32. As illustrated in FIG. 3B, a first screen-like element 36-1 is attached to the back side 30-B of the false wall 30 to cover the water inlet openings 34 on the first lateral side of the water outlet opening 32 and a second screen- like element 36-2 is attached to the back side of the false wall 30 to cover the water inlet openings 34 on the second lateral side of the water outlet opening 32. Each of the screen-like elements can 36-1, 36-2 can comprise a sheet of perforated polypropylene having a thickness of 0.25 inches, or any other suitable perforated material that is corrosion-resistant in water. The screen-like elements 36-1, 36-2 can be attached to the back side of the false wall 30 with conventional fasteners that are made from a material that is corrosion-resistant in water. The screen-like elements 36-1, 36-2 prevent hair, other debris, bathing caps and the like from entering the pump compartment 40. The screen-like elements 36-1, 36-2 also prevent the swimmer's hands, feet, head and the like from entering the pump compartment 40. As best illustrated in FIGS. 2C and 3D, the false wall 30 is securely retained between the sidewalls 20-3, 20-4 of the spa shell 20 by attaching the lateral mounting flanges 30-LF of the false wall 30 against corresponding front surfaces S of the flutes 44-F of the pump compartment sidewalls (portions 40-1, 40-2 of respective sidewalls 20-3, 20-4 of spa shell 20) with conventional fasteners that are made from a material that is corrosion-resistant in water. The outer edge of each false wall lateral flange 30-LF abuts against a locating element or rib 38 positioned in front of the flutes 44-F on the sidewall 20-3, 20-4 of the spa shell 20.

Referring collectively now to FIGS. 4A-4C, the top deck 50 is configured as a generally rectangular tray-shaped member having a front end 50-F, a back end 50-B, and sides 50-S. A peripheral rim 52 extends along the back end 50-B and sides 50-S of the top deck 50 and a ribbed cover wall 54 slopes downward from a back portion of the peripheral rim 52 to the front end 50-F of the top deck 50 to deter users/swimmers from standing or sitting of the top deck 50. A flange 56 depends from an outer edge of the peripheral rim 52 to strengthen the peripheral rim 52 and to eliminate a sharp edge at the outer edge of the peripheral rim 52. Triangular-shaped sidewalls 58 connect the cover wall 54 to side portions 52-S of the peripheral rim 52. A light 59 can be provided on a top side 54-T of the cover wall 54. The peripheral rim flange 56 of the top deck 50 is supported on a ledge feature L formed on the back 20-2 and sidewalls 40-1, 40-2 of the pump compartment 40. The downwardly sloping top surfaces 44-FS of the fluted sidewall sections 44-F of the pump compartment 40 support the downward sloping cover wall 54 of the top deck 50.

The spa shell 20, false wall 30 and top deck 50 can each be formed of a durable, lightweight, high-strength material including for example, but not limitation, a thermoformable acrylic material or any other suitable plastic material using any suitable plastic forming method.

Referring again to FIG. 5A and now to FIGS. 5B-5E, the blower-type water pump 110 includes a scroll-shaped blower housing 112 and the earlier-mentioned centrifugal blower impeller 114 rotatively disposed within the blower housing 112. The blower housing 112 has opposing first and second central, axial water inlets 112-1, 112-2 (FIG. 5E), each of which is defined by an annular, inwardly curving lip 112-L1, 112-L2. The blower housing 112 further includes the earlier mentioned tangential water discharge outlet 112-O. As illustrated in FIG. 6, the distance between an outer periphery of the blower impeller 114 and an inner surface of the blower housing increases moving in a direction toward the water discharged outlet 112-O. In some embodiments, the distance between the outer periphery of the blower impeller and the inner surface of the blower housing at points A, B, and C can be 1.17 inches, 3.30 inches, and 4.47 inches, respectively. In other embodiments, the distance between the outer periphery of the blower impeller and the inner surface of the blower housing at points A, B, and C can be other dimensions. The blower housing 112 can be formed from any suitable, highly chemical resistant plastic material using any suitable plastic forming method. For example, in some embodiments, the blower housing 112 can be vacuum formed or rotomolded (rotational molding) from Acrylonitrile Butadiene Styrene (ABS).

As shown in FIGS. 5A, 5B, and 5E, first and second driveshaft bearing brackets 116-1, 116-2 are positioned and attached at their ends to respective sides of the blower housing 112, across the water inlet lips 112-L1, 112-L2 (FIG. 5E). Each bearing bracket 116-1, 116-2 includes a bearing 116-B1, 116-B2 located on a center axis CA of its respective blower housing water inlet lip 112-L1, 112-L2. The bearing brackets 116-1, 116-2 and the bearings 116-B1, 116-B2 rotatively mount the earlier-mentioned driveshaft 124 and the centrifugal blower impeller 114 on the center axis CA of the blower housing water inlet lips 112-L1, 112-L2. The bearing brackets 116-1, 116-2 and the bearings 116-B1, 116-B2 are made of a material that is corrosion/chemically-resistant in the water of a spa environment, such as stainless steel or acetal plastic. In other embodiments, the first driveshaft bearing bracket 116-1 and bearing 116-B1 can be omitted. The driveshaft 124 extends through a central hub 114-H of the blower impeller 114, which hub 114-H is in line with the center axis CA (which is a central axis of the blower impeller and the center axes of the blower housing water inlet lips 112-L1, 112-L2), so that its second end 124-2 is rotatively mounted in the second bearing 116-B2. The driveshaft 124 can be coupled to the central hub 114-H of the blower impeller 114 with a keyed shaft coupling arrangement (not visible). In some embodiments, the driveshaft 124 is made from a stainless steel, which is exhibits corrosion/chemical-resistance in the water of a spa environment, and has a diameter of 1 inch or any other suitable diameter, which allows a faster ramp up time (the time it takes for the blower impeller 114 and driveshaft 124 to go from idle to full rotation speed) to get to operating speed without destructive twisting of the driveshaft 124 due to torsional forces. The water pump mounting brackets 112-BK are each attached to a respective side of the blower housing 112. The water pump mounting brackets 112-BK are made of a material that is corrosion/chemical-resistant in the water of a spa environment, such as Fiberglass Reinforced Polypropylene.

Referring collectively to FIGS. 7A-7D, the centrifugal blower impeller 114 comprises first and second ring-shaped outer members 114-R1, 114-R2 (first and second blade support rings 114-R1, 114-R2), and a disc-shaped inner member 114-D (blade support disc 114-D) positioned between the first and second blade support rings 114-R1, 114-R2. The element positioned on the central axis CA (which extends through a center of the blade support disc 114-D/impeller 114) is the earlier-mentioned central hub 114-H of the blower impeller 114. The central hub 114-H is disposed within and connected with the blade support disc 114-D. A plurality of arcuate-shaped blades 114-B are positioned about the central axis CA of the blower impeller 114. Each blade 114-B is split into a first blade element 114-B1 that extends between the first blade support ring 114-R1 and the blade support disc 114-D and a second blade element 114-B2 that extends between the second blade support ring 114-R2 and the blade support disc 114-D. The region defined by the first blade elements 114-B1 and the blade support disc 114-D forms a first cylindrical cavity 114-C1 (FIG. 7B). The region defined by the second blade elements 114-B2 and the blade support disc 114-D forms a second cylindrical cavity 114-C2 (FIG. 7C). In a preferred embodiment, the blade support rings 114-R1, 114-R2, the blade support disc 114-D, the central hub 114-H and the blades 114-B are made from a plastic material, such as polypropylene or fiberglass reinforced polypropylene, using any suitable plastic forming process, such as injection molding.

In some embodiments (now shown), the centrifugal blower impeller 114 comprises only a single ring-shaped outer member configured like the earlier described ring-shaped outer members 114-R1/114-R2, a disc-shaped outer member configured like the earlier described inner disc-shaped member 114-D, which includes the earlier-described central hub 114-H disposed within and connected with the disc-shaped outer member, and a plurality of arcuate-shaped blades configured like the first/second blade elements 114-B1/114-B2 of the blade 114-B and extending between the single ring-shaped outer member and the disc-shaped outer member. The single ring-shaped outer member and disc-shaped outer member of this embodiment only defines a single cylindrical cavity and the blower housing of this embodiment, only has a single central, axial water inlet communicating with the single ring-shaped outer member.

As illustrated in FIG. 7E, each of the first and second blade elements 114-B1, 114-B2 of a blade 114-B has a top edge TE, a bottom edge BE, and a convex pressure surface PS. The convex pressure surface PS (or in other words backwards curved blade configuration) provides better water current flow and more efficient power consumption. In particular, this blade configuration allows motor operation within an optimal power curve (60 Hz) using smaller gear ratios (i.e., pulley 122 t pulley 132 diameter ratios).

As illustrated in FIG. 7G, the blades are circumferentially spaced apart from one another on the blower impeller 114 by a certain distance D to optimize the performance and power efficiency of the water pump 110. For example, in one non-limiting embodiment, the distance D is measured from the crest of the convex pressure surface PS of each of the blade elements 114-B1, 114-B2 of each blade 114-B and the bottom edges BE of each of the blade elements 114-B1, 114-B2 of an adjacent blade 114-B, can be 1.28 inches. Distance D in other embodiments can be greater or less than 1.28 inches.

As illustrated in FIG. 7H, in some embodiments, each blade element 114-B1, 114-B2 of a blade 114-B can have a width W, as measured between the top edge TE and the bottom BE of the blade element114-B1, 114-B1, of 1.40 inches. Further, the blades 114-B are mounted on the blade support rings 114-R1, 114-R2 and blade support disc 114-D at an attack angle Φ measured between line T-B, which connects the top edge TE and the bottom edge BE of the blade element 114-B1, 114-B2, and line P, which is perpendicular to the blade support rings 114-R1, 114-R2 at that blade 114-B, so that the top edges TE of the blade elements 114-B1, 114-B2 of each blade 114-B leads the bottom edges BE of that blade 114-B. In a preferred embodiment, the attack angle Φ is 24.5 degrees. The attack angle in other embodiments can range from about 13 degrees to 40 degrees.

Referring again to FIGS. 7B and 7C, a screw fastener or rivet 114-F can be used to secure and retain the outer end of each blade element 114-B1, 114-B2 of a blade 114-B to its respective blade support ring 114-R1, 114-R2 at the selected attach angle. The screw fasteners or rivets 114-F extend through openings O in the blade support rings 114-R1, 114-R2.

Referring to FIG. 6, in operation, the blades 114-B disposed around the center axis CA of the blower impeller 114 draw water through the water inlets 112-1, 112-2 of the blower housing 112 (FIG. 5E) into the first and second cavities 114-C1 and 114-C2, respectively, of the impeller 114 along the center axis CA of the impeller 114 (FIGS. 7A-7C), as the impeller rotates in a direction R toward the water discharge outlet 112-0 of the water pump housing 112, and pushes the water radially outward from the first and second cavities 114-C1 and 114-C2 of the impeller 114 toward the outer periphery of the blower impeller 114. The scroll-shaped pump housing 112, which accommodates the blower impeller 114, includes a water passage WP having a scroll shape. The water pushed radially outward by the blower impeller 114 enters and flows through the water passage WP of the pump housing 112 toward and out through the water discharge outlet 112-O thereof. The water discharged from the water discharge outlet 112-0 of the pump housing 112 passes through the grate 118 disposed in the duct-like water outlet opening 32 of the false wall 30 (FIG. 1A and FIG. 3A) into the water contained in the swimming/bathing compartment 60 of the spa shell 12.

Referring to FIG. 8D, the grate 118 comprises a square or rectangular block of straw-like tubes that straightens the turbulent flow of water discharged from the water discharge outlet 112-O of the pump housing 112, thus increasing the laminar flow of water directed at a swimmer swimming in the swimming/bathing compartment 60 of the spa shell 20, thus, making for a much smoother swim experience for the swimmer. The grate 118 can be made of any suitable plastic material. For example, in some embodiments, the grate 118 is made of a polycarbonate thermoplastic material.

Referring collectively to FIGS. 8A-8C, is an embodiment of a grate frame 150 for removably holding the grate 118. The grate frame 150 is typically formed as a square or rectangular member. The grate frame 150 has an open first side 150-1 that faces the water discharge outlet 112-O of the water pump housing 112 and a second side 150-2 with a grid of diagonal bars 150-B that face the swimming/bathing compartment 60 of the spa shell 20 (FIG. 1A) and hold the grate 118 within the gate frame 150. The grate frame 150 is hingedly retained within the duct-shaped water outlet opening 32 of the false wall 30 (FIG. 3A) by a living hinge element 152 that has one leaf 152-L1 (FIG. 8C) attached to a bottom of the grate frame 150 and a second leaf 152-L2 attached to a bottom wall of the duct-shaped water outlet opening 32 (not shown). A pair of flanges 150-F are formed on a top of the grate frame 150, which allow the grate frame 150-F to be connected to a link member 166 of a grate angle-adjustment mechanism 160 (FIGS. 9A-9C). The grate frame 150 can be formed from any suitable plastic material. For example, in some embodiments, the grate frame 150 is vacuumed formed from acrylonitrile butadiene styrene (ABS) thermoplastic material. The living hinge element 152 can be made of any suitable plastic material. For example, in some embodiments, the living hinge element 152 is made of a polyolefin thermoplastic material.

Referring collectively to FIGS. 9A-9C, is an embodiment of the grate angle-adjustment mechanism 160. The grate angle-adjustment mechanism comprises a threaded rod member 162, a U-shaped collar member 164, and a link member 166. The threaded rod member 162 extends through the false wall 30 such that a short section of the threaded rod member extends out from the front side 30-F of the false wall 30 and a substantially longer section of the threaded rod member 162 extends out from the back side 30-B of the false wall 30. A knob 168 is attached to or formed on the end of the short section of threaded rod member 162 extending out from the front side 30-F of the false wall 30, which allows the swimmer/user to rotate the threaded rod member 162 in a clockwise or counter clockwise direction. The U-shaped collar member 164 is configured to threadedly engage the substantially longer section of the threaded rod member 162 and travel back and forth along the threaded rod member 162 when the threaded rod member 162 is rotated clockwise and counter clockwise. The collar member 164 is connected to a first end of a link member 166 and a second end of the link member 166 is connected to the pair of flanges 150-F formed on the top of the grate frame 150. The angle of the grate frame 150 holding the grate 118 can be adjusted by the swimmer/user while in the swimming/bathing compartment 60 of the spa shell 20 to any angle between 0 degrees and 20 degrees, by simply rotating the knob 168 of the grate angle-adjustment mechanism 160. Adjusting the angle of grate 118 so that it points towards the surface of the water to direct the flow to specifically keep the swimmer aloft more easily in the water for a better quality swim experience. In a preferred embodiment, the angle of the grate 118 is adjusted to about 15 degrees. Angles greater and less than 15 degrees can be used depending upon the height of the swimmer or personal preference. For example, but not limitation, using less than 15 degrees may help swimmers of a shorter height get a similar lift as compared to a taller swimmer. However, the setting on a taller person may not provide as much lift during the exercise. Furthermore, adjusting the grate 118 to an upward angle typically produces a good swim window and allows “return flow” water to flow back underneath of the swimmer, towards the false wall 30, thereby entering the inlet openings 34 and the water pump 110. This in turn reduces any swirling water affect that produces a cross flow in front or between the swimmer and the propulsion system 100. If the is directed straight without an incline, the flow of water can produce a cross flow that is undesirable to the swimmer. More specifically, adjusting the angle of the grate 118 advantageously reduces or negate the cross current or cross flow that would affect the swimming position, i.e., the cross current can force the swimmer to fight to stay centered in the spa making for a difficult and less desirable swim experience.

It should be understood that the invention is not limited to the embodiments illustrated and described herein. Rather, the appended claims should be construed broadly to include other variants and embodiments of the invention, which may be made by those skilled in the art without departing from the scope and range of equivalents of the invention. It is indeed intended that the scope of the invention should be determined by proper interpretation and construction of the appended claims and their legal equivalents, as understood by those of skill in the art relying upon the disclosure in this specification and the attached drawings.

Claims

1. A water propulsion system for generating a directed flow of water in a swim-exercise apparatus, comprising:

a water pump including: a scroll-shaped blower housing; and a centrifugal blower impeller rotatively disposed within the blower housing; and

a motor for rotatively driving the centrifugal blower impeller;

wherein the centrifugal blower impeller includes a plurality of arcuate-shaped blades positioned about a central axis of the centrifugal blower impeller, each of the blades having a convex-shaped water pressure surface.

2. The water propulsion system of claim 1, further comprising a pump impeller drive arrangement including:

a first pulley;

a driveshaft; and

a drive belt;

wherein a first portion of the driveshaft is coupled to the first pulley and a second portion of the driveshaft is coupled to centrifugal blower impeller;

wherein the electric motor includes a second pulley; and

wherein the drive belt rotatively couples the second pulley of the electric motor to the first pulley coupled to the first portion of the driveshaft of the pump impeller drive arrangement.

3. The water propulsion system of claim 1, wherein the blower housing has a scroll-shape and includes a central, axial water inlet and a tangential water discharge outlet.

4. The water propulsion system of claim 3, wherein a distance between an inner surface of the blower housing and an outer periphery of the centrifugal blower impeller increases moving in a direction toward the water discharged outlet of the blower housing.

5. The water propulsion system of claim 1, wherein the centrifugal blower impeller further includes a ring-shaped outer member and a disc-shaped outer member, and wherein the plurality of arcuate-shaped blades extend between the outer ring-shaped member and the disc-shaped outer member.

6. The water propulsion system of claim 1, wherein the centrifugal blower impeller further includes first and second ring-shaped outer members and a disc-shaped inner member positioned between the first and second ring-shaped outer members, and wherein the plurality of arcuate-shaped blades includes a first blade element extending between the first ring-shaped outer member and the disc-shaped inner member and a second blade element extending between the second ring-shaped outer member and the disc-shaped inner member.

7. A swim-exercise apparatus, comprising:

a water containment vessel having a first area defining a swimming/bathing compartment for enabling a user to swim-in-place within the apparatus; and

a water propulsion system for generating a directed flow of water in the swimming/bathing compartment of the water containment vessel, the water propulsion system comprising: a water pump including: a scroll-shaped blower housing; and a centrifugal blower impeller rotatively disposed within the blower housing; and a motor for rotatively driving the centrifugal blower impeller;

wherein the centrifugal blower impeller of the water pump of the water propulsion system includes a plurality of arcuate-shaped blades positioned about a central axis of the centrifugal blower impeller, each of the blades having a convex-shaped water pressure surface.

8. The swim-exercise apparatus of claim 7, wherein the water pump is disposed in a pump compartment defined in a second area of the water containment vessel.

9. The swim-exercise apparatus of claim 8, wherein the pump compartment is formed by at least one wall of the water containment vessel and a false wall that separates the pump compartment from the swimming/bathing compartment of the water containment vessel, wherein the false wall includes a water outlet opening and at least one water inlet opening, and wherein the water outlet opening is aligned with a water discharged outlet of the blower housing of the water pump.

10. The swim-exercise apparatus of claim 9, further comprising a top deck for covering the pump compartment.

11. The swim-exercise apparatus of claim 10, wherein the top deck is a tray-shaped member having a ribbed cover wall that slopes downward toward the swimming/bathing compartment of the water containment vessel.

12. The swim-exercise apparatus of claim 9, wherein the at least one wall of the water containment vessel is fluted to increase the structural integrity of the pump compartment.

13. The swim-exercise apparatus of claim 9, further comprising a screen-like element is attached to a back side of the false wall to cover the at least one water inlet opening.

14. The swim-exercise apparatus of claim 9, further comprising a grate disposed in the water outlet opening of the false wall, the grate for straightening the turbulent flow of water discharged from the water discharge outlet of the blower housing, thereby increasing a laminar flow of water directed at the user in the swimming/bathing compartment of the water containment vessel.

15. The swim-exercise apparatus of claim 14, further comprising a grate angle-adjustment mechanism that includes a knob disposed on a front side of the false wall for enabling the user to adjust the angle of the grate relative to the water discharge outlet of the blower housing to change a direction of water discharged through water outlet of the blower housing.

16. The swim-exercise apparatus of claim 7, further comprising a pump impeller drive arrangement including:

a first pulley;

a driveshaft; and

a drive belt;

wherein a first portion of the driveshaft is coupled to the first pulley and a second portion of the driveshaft is coupled to centrifugal blower impeller;

wherein the electric motor includes a second pulley; and

wherein the drive belt rotatively couples the second pulley of the electric motor to the first pulley coupled to the first portion of the driveshaft of the pump impeller drive arrangement.

17. The swim-exercise apparatus of claim 16, wherein the first pulley, the first portion of the driveshaft, the drivebelt, and the electric motor are disposed outside of the water containment vessel.

18. The swim-exercise apparatus of claim 17, further comprising a frame for supporting the water containment vessel, and a cabinet to enclose the frame, the first pulley, the first portion of the driveshaft, the drivebelt, and the electric motor.

19. The swim-exercise apparatus of claim 7, wherein the blower housing has a scroll-shape and includes a central, axial water inlet and a tangential water discharge outlet.

20. The swim-exercise apparatus of claim 19, wherein a distance between an inner surface of the blower housing and an outer periphery of the centrifugal blower impeller increases moving in a direction toward the water discharged outlet of the blower housing. 21 The swim-exercise apparatus of claim 7, wherein the centrifugal blower impeller further includes a ring-shaped outer member and a disc-shaped outer member, and wherein the plurality of arcuate-shaped blades extend between the outer ring-shaped member and the disc-shaped outer member.

22. The swim-exercise apparatus of claim 7, wherein the centrifugal blower impeller further includes first and second ring-shaped outer members and a disc-shaped inner member positioned between the first and second ring-shaped outer members, and wherein the plurality of arcuate-shaped blades includes a first blade element extending between the first ring-shaped outer member and the disc-shaped inner member and a second blade element extending between the second ring-shaped outer member and the disc-shaped inner member.

23. The swim-exercise apparatus of claim 7, wherein the swim-exercise apparatus is a swim spa and the water containment vessel is a spa shell.

24. A method of propelling water against a swimmer in a swim-exercise apparatus so that the swimmer can swim in a generally stationary position, against the force of the water, thereby simulating swimming forward in the water of the swim-exercise apparatus, the method comprising:

providing a water propulsion system in a section of a water containment vessel of the swim-exercise apparatus; and

generating, with the water propulsion system, a directed flow of water in a swimming/bathing compartment of the water containment vessel of the swim-exercise apparatus;

wherein the water propulsion system comprises a water pump including: a scroll-shaped blower housing; and a centrifugal blower impeller rotatively disposed within the blower housing; and a motor for rotatively driving the centrifugal blower impeller;

wherein the centrifugal blower impeller of the water pump of the water propulsion system includes a plurality of arcuate-shaped blades positioned about a central axis of the centrifugal blower impeller, each of the blades having a convex-shaped water pressure surface.