AU2010249203B2 - Spa with Variable Water Circulation Provisions - Google Patents

Abstract

A recreational spa comprising a plurality of seating positions, each having a plurality of water jet nozzles arranged in discrete groups; means to detect occupancy of a seating position; control panels at each seating 5 position incorporating controls to initiate water flow to said groups of water jets and to control the energy of discharge, temperature and degree of aeration of the water flows and lighting provisions of said spa; and one or more water pumps, the output volume and pressure of which are universally variable over a large range and thereby provide economy of 10 energy consumption. Sheet 1 of 2

Description

2010249203 07 Dec 2010

ORIGINAL

Australia

Patents Act 1990

Complete Specification for the Invention Entitled SPA WITH VARIABLE WATER CIRCULATION PROVISIONS

The invention is described in the following statement: 2 2010249203 07 Dec 2010

SPA WITH VARIABLE WATER CIRCULATION PROVISIONS

This invention relates generally to recreational spas into which water jets or combined water and air jets are emitted for hydro massage or hydrotherapy purposes. In particular, it relates to recreational spas in 5 which water or combined water and air jets are emitted in controllable ways to generate specific hydro massage or hydrotherapy effects.

In the operation of recreational spas, it is common for water jets or combined water and air jets to be discharged into the body of water generally to provide a pleasant stimulatory effect to users. It is also 10 common for such jets to be discharged into particular zones of a spa to impinge upon the bodies of seated users, impingement of the jets inducing a massaging effect which is relaxing and useful in the relief of stress, muscular tension and physical fatigue. Spa jets are commonly made with adjustable flow volume and pulsed flow, the flow pulsation being induced 15 by rotating elements that intermittently occlude flow ports or by fluidic effects. Various pump combinations may be employed to increase or decrease jet flow. Air is optionally introduced into the jet flow, either by venturi effect or by positive flow from a pressurised source. The water or air flow emitted by the jet is optionally heated. The operation and 20 arrangement of such jets is well known in the art and requires no elucidation. It will be appreciated from the foregoing that a considerable difference will exist between the volume flow required from the jets of a spa when used by only a single user and when used by the maximum number of users for which a spa is designed. 3 2010249203 07 Dec 2010

Where an increased volume flow is required to operate additional jet combinations, it is common for additional pumps to be brought into operation. This is particularly so in spas having large numbers of jets in groups, the operation of which is required only selectively. An example is 5 the Model LSX 1000 spa manufactured by Master Spas, Inc., 6927 Lincoln Parkway, Fort Wayne, IN. 46804, USA which has up to 115 jets in a variety of separately controllable combinations in seven seating positions. The jets are supplied with water by five separate pumps in the form of two dual-speed pumps and two single-speed pumps, with a 10 separate circulation pump in continuous operation for filtration, ozonation, and heating purposes, as needed. The total power output of the pump motors, with all spa jets operating, is approximately 15.75 kilowatts. The seating positions of the Model LX 1000 have various numbers and arrangements of jets which are selectable and adjustable to provide a 15 variety of effects. Spa seating units incorporating hydrotherapy provisions are well known in the art and a typical example is that taught by Livingston in US 5,418,984. In this invention, a seating unit is moulded into the side wall of a spa, a shell sealingly fixed to it creating a manifold chamber between the two. Pressurised water circulated to the manifold 20 chamber is emitted in jets through a plurality of small diameter apertures in the seating unit, imparting to an occupant a gently massaging effect. In other examples taught by Weir in US 5,228,148 and 5,333,322, seating units incorporating hydrotherapy water/air jets are moulded into the side of a swimming pool or suspended from a coping element forming the 4 2010249203 07 Dec 2010 transitional piece at the comer of the vertical wall and the horizontal deck of the swimming pool.

Hitherto, when additional water flow was required in order to bring into operation additional water jets, the options available were to 5 operate more pumps or to increase the output flow of an already operating pump. The latter option was limited to removing an inhibition imposed upon the output of a pump through discharge throttling or recycling of flow, both of which are inefficient and wasteful of energy. Although the operating principle of variable speed centrifugal pumps has been known 10 for some time, the adoption of this innovation for smaller systems, such as spas has been largely neglected. The reasons for this have been several: resistance to new technology, technical difficulties with matching pump output to large changes in system flow requirements; and a reputation for unreliability of electronic components. Suitably designed installations can 15 now be made to have very low failure rates and the body of knowledge and design skills necessary to create systems with the flexibility to seamlessly accommodate a broad range of flow configurations is now available. A first object of the present invention is to provide a spa system 20 employing a water pumping system based upon one or more variable-speed pumps which operate to provide a continuous low flow for filtration, ozonation, and heating purposes, but which can rapidly and seamlessly increase output to supply the water required to power the various jet combinations of a plurality of spa seating stations. A second 5 2010249203 07 Dec 2010 object of the present invention is to provide a water pumping system which is controlled by a microprocessor-based control unit and which automatically responds to functional commands deliberately made by spa users using controls provided and implicit commands made by spa users 5 by their occupation of seating positions. A third object of the present invention is to provide a microprocessor-based control unit which automatically regulates air flow, water temperature and air temperature in relation to said water flow in response to functional commands deliberately made by spa users using controls provided. 10 According to the present invention, a spa is provided in which one or more centrifugal pumps of suitable flow characteristics are driven at variable speeds to provide the pressures and flow rates necessary to deliver all spa functions. The pump drive motors are controlled in accordance with a stored program run in a microprocessor-based control unit which 15 determines, for a particular selected configuration, the commencement of operation of each pump and the RPM at which each pump is operated. Selections of particular spa configurations made by spa users provide signals to the control unit. Other signals are provided to the control unit from water or air pressure sensors, water or air flow sensors, water or air 20 temperature sensors and occupation sensors which detect the occupation of spa seating positions. In addition to the operation of the pump motors, the control unit opens or closes valves to control water and air flows to specific parts of the spa.

The various aspects of the present invention will be more readily 6 2010249203 07 Dec 2010 understood by reference to the following description of preferred embodiments given in relation to the accompanying drawings in which:

Figure 1 is a schematic diagram of the water circulation arrangements of a spa made according to the present invention; 5 Figure 2 is a longitudinal cross-sectional view of a flow restricting valve forming part of the water circulation arrangements of Figure 1;

Figure 3 is a face view of an alternative form of flow restricting valve. 10 With reference to Figure 1, spa 1 is made with four seating positions 2, 3, 4, 5. Said seating positions incorporate water distribution manifolds (not shown) which deliver flows of water to a plurality of nozzles (not shown) in each said seating position. Different said seating positions optionally have their said nozzles arranged in a variety of arrays, 15 said nozzles emitting water jets which impinge upon the bodies of persons seated therein. Said water jets are optionally larger or smaller, steady or pulsed flow, aerated and/or heated. Water is drawn off from said spa by one or more pumps 16, 17 via a small sump 19 and supply line 18. The output of said pumps is delivered via first delivery line 15 to diversion 20 valve 14. At low output volume of said pumps, said diversion valve directs a small steady flow of water to said spa via second delivery line 32 and filter unit 33 and sterilisation unit 34. At high output volume of said pumps, said diversion valve directs the additional water flow via third delivery line 13, fourth delivery line 12, fifth delivery lines 11, 25, short 7 2010249203 07 Dec 2010 connections 10, 24, and distributors 6, 7, 20, 21 respectively to said nozzles of seating positions 4,5,2, 3. Solenoid valves 8, 9,22,23 in said distributors are employed to interrupt flow to said seating position nozzles, as required. The lengths and diameters of said delivery lines connecting 5 said pumps to said seating positions are designed to ensure equal pressure drops between said pumps and all said seating positions. A flow of air is delivered to short connections 10,24 via air lines 31,28. In the preferred embodiment, said flow of air is supplied from a suitable pressurised source (not shown). In an alternative embodiment, said flow of air is drawn from 10 ambient, said flow being induced by water flow through venturis (not shown) positioned at the junctions of said fifth delivery lines and said air lines with said short connections. Suitable heater units 26,29 are provided in fifth delivery lines 11, 25 to heat said water flows. In the preferred embodiment, said heater units are electrical resistance heaters. In 15 alternative embodiments, said heater units operate by the combustion of any suitable fuel. Similar heater units 27, 30 are optionally provided in air lines 28, 31 to heat said inflowing supply of air.

Each said seating position has conveniently located to it a control panel 35, 36, 37, 38 incorporating controls (not shown) used to regulate 2 0 any of water jet energy, water jet temperature, aeration air temperature, aeration level of water or lighting, or selection of all or specific groups of nozzles in that seating position. Operation of said controls generates signals (depicted as 39 for control panel 35) which are transmitted to a microprocessor-based control unit 40. Sensors (not shown) provided in 8 2010249203 07 Dec 2010 said seating positions detect the presence of a seated user and provide an occupancy signal (depicted as 41 for seating position 4) to said control unit. In the preferred embodiment, said sensors take the form of suitable pressure pads incorporated into the surface of said seating positions. In 5 alternative embodiments, said sensors take the form of light-dark sensors, force sensing resistors, piezo film sensors or the like, adapted for the purpose. Pumps 16, 17 are electrically driven, variable speed, centrifugal pumps and control unit 40 provides control inputs 42, 43 to the motors of said pumps to regulate their speeds of operation and, thereby, the water jet 10 energy at all or part of the nozzles of a particular seating position. Said control unit also controls the operation of heater units 26, 29, 27, 30 to regulate the temperature of water or air emitted from said seating position nozzles, the aeration level of water jets emitted from said seating position nozzles, the operation of spa lighting appliances (not shown), or the 15 bringing into operation or taking out of operation specific groups of seating position nozzles. The aeration level of said water jets is regulated by controlling the flow of air through air lines 28, 31, said control being effected by means of suitable throttling valves (not shown). In the preferred embodiment, said throttling valves take the form of suitable 20 slide, gate or butterfly valves operated by suitable remotely-controllable actuators. The bringing into operation or taking out of operation specific groups of seating position nozzles is effected by means of suitable solenoid valves (not shown) provided in said seating position water distribution manifolds. Water and air flows to said seating positions are 9 2010249203 07 Dec 2010 cut off by means of solenoid valves 8,9,22,23.

At times during which a spa is unoccupied, a single said pump operates at low RPM, generating a continuous flow of water in the range 40 to 250 litres per minute. Said flow passes via diversion valve 14 which 5 directs flow via filter unit 33 and sterilisation unit 34 and thence via second delivery line 32 to said spa. In another alternative embodiment (not shown), said second delivery line also incorporates a heater unit which acts to maintain the body of water contained in said at a preselected temperature. In this embodiment, one or more temperature 10 sensing elements are provided which transmit temperature signals to said control unit. Said control unit regulates the operation of said heater unit. Said continuous water flow through said second delivery line acts to cycle most of the body of water contained in said spa through said filter and sterilisation units, thereby removing suspended and dissolved material and 15 sterilising biological organisms. In the preferred embodiment, said filter unit takes any of the forms of filter commonly used with spas, swimming pools and the like and well known in the art. Also in the preferred embodiment, said sterilisation unit takes any of the forms of sterilisation unit commonly used with spas, swimming pools and the like and well 20 known in the art. In alternative embodiments (not shown), any function normally occurring on the delivery side of a pump, such as sterilisation, filtration or the like, optionally occurs on the suction side of said pump.

When said spa is occupied and one or more of said seating positions are in use, the output of said pump or pumps is increased. With 10 2010249203 07 Dec 2010 reference to Figure 2, second delivery line 32 has provided in it valve chamber 44. Said valve chamber encloses valve cage 45 which communicates with said second delivery line at the upstream end of said valve chamber. Said valve cage is provided with outlet opening 47 at its 5 downstream end and a plurality of secondary outlets 46 formed in its side walls. A plurality of valving leaves 48, equal in number to said secondary outlets and made from a thin, stiffly elastic material, are supported from the inner surface of flat, downstream face 51 of said valve cage, said valving leaves being located in positions aligned with said secondary 10 outlets and elastically deflected inwardly and away from said secondary outlets. At times of low water flow with said secondary outlets uncovered, the total cross-sectional area of said outlet opening and said secondary outlets is such that a full and unimpeded flow of water is able to pass across said valve chamber. When the output of said pumps is increased, 15 said valving leaves are elastically displaced against the side walls of said valve cage, thereby closing said secondary outlets and reducing water flow to that able to be passed through said outlet opening. The flow of water through said outlet opening is determined by its cross-sectional area and normally falls in the range 40 to 250 litres per minute. 20 With reference to Figure 3, in an alternative embodiment, second delivery line 32 is provided with a bifurcated section comprising two short lines 49, 50. Short line 49 is made with an internal cross-sectional area in the range 1 to 8 times that of short line 50 and is provided with a remotely-controllable flow control valve 52 which may be employed to close it off. 11 2010249203 07 Dec 2010

In the preferred embodiment, said flow control valve is a solenoid valve. At times of low water flow, said flow control valve is open and the full flow of said second delivery line is able to pass across said bifurcated section. When the output of said pumps is increased, said flow control 5 valve is closed, reducing water flow to that able to be passed through short line 50. The flow of water through short line 50 is determined by its cross-sectional area and normally falls in the range 40 to 250 litres per minute.

Said controls at control panels 35, 36, 37, 38 include means to select high or low water jet energy from the selected array of said seating 10 position nozzles. With reference again to Figure 3, a short bifurcated section of the nature described is provided in each of distributors 6, 7,20, 21. High water jet energy is achieved by opening flow control valve 52 and low water jet energy by closing said flow control valve.

Said control unit contains a stored program which covers all 15 possible configurations and combinations of occupied seating position, water nozzle combinations, water jet energy, water temperature, air temperature and degree of water aeration. Upon receiving configuration signals from a particular occupied seating position, said control unit refers to a look-up table and determines, for the totality of occupied seating 20 positions and their selected configurations, the operation and speed of operation of said pump or pumps, the opening or closing of diversion valve 14, the opening or closing of solenoid valves 8, 9, 22, 23, the operation of heater units 26,29, 27, 30, the opening or closing of said flow control valve in second delivery line 32, the opening or closing of said 12 2010249203 07 Dec 2010 flow control valve in distributors 6, 7, 20, 21, the opening or closing of valves in air lines 28, 31 and the opening or closing of said solenoid valves in said seating position water distribution manifolds. Said opening or closing of said solenoid valves in said seating position water distribution 5 manifolds is optionally employed to direct water to nozzles emitting water jets in steady flow or to nozzles from which pulsed water jets are emitted. Said control unit optionally receives signals from suitably located water or air pressure sensors (not shown), water or air flow sensors (not shown) and water or air temperature sensors (not shown) suitably located in said water 10 and air delivery conduits or lines. Said signals from said sensors permit said control unit to better control preselected operational parameters.

Said water pumps are variable speed centrifugal pumps driven by electric motors. Because of the greater magnitude of advantage available, variable speed pumps have hitherto been substantially confined to larger 15 applications. Improvement of the technology now permits smaller pumps suitable for use in a spa to be operated under variable speed drive. Under variable speed drive, pump speed is controlled by varying the frequency and voltage supplied to the drive motor. This provides a relatively constant ratio of voltage to frequency as required by the characteristics of 20 the AC motor to generate torque. In closed-loop control, a change in process demand is compensated by a change in power and frequency supplied to the motor, thereby producing a change in motor speed. The ability of variable speed drive centrifugal pumps to reliably provide both variable water flow and pressure over a wide range makes them ideally 2010249203 07 Dec 2010 13 suited to use in a spa. Although not immediately suited for use in a spa, an example which illustrates the potential of variable speed centrifugal pumps is the Model Hydro 2000 ME 1 CRE64 manufactured by Grundfos Holding A/S, Poul Due Jensens Vej 7, DK-8850 Bjerringbro, Denmark. 5 This pump is capable of providing a minimum flow of approximately 150 litres per minute at a head of 4 metres through to a maximum flow of 1,400 litres per minute at a head of 15 metres. At a constant head of 20 metres, it can provide a universally variable flow in the range 216 litres per minute to 1,133 litres per minute. A further example with a capacity 10 more appropriate to a spa is the Model VS-3050 manufactured by Pentair Water Pool and Spa, Inc., 10951 W Los Angeles Avenue, Moorpark, CA 93021, USA. This unit can deliver outputs ranging from less than 50 litres per minute at 750 RPM and a head of approximately 2.5 metres to 550 • litres per minute at 3,450 RPM and a head of 17.5 metres. While the 15 control unit supplied with this unit provides for operation at specific pump speeds, the drive motor is capable of operation at universally variable speeds.

The use of one or more variable-speed pumps permits pump output to be precisely and almost instantaneously matched to the water 20 flow requirements of a spa. As a result, it provides the greatest operational flexibility of spa operation, reduces electrical power consumption and reduces pump costs when compared with the fixed-speed or stepped-speed pumps which are commonly employed in spas.

Claims (14)

1, An integrated water and air circulation system for a recreational spa having multiple seating positions with controllable jets in each, said system comprising: • Electronic means to detect occupancy of a seating position; • One or more variable-speed centrifugal water pumps each drawing a supply of water from the body of water of said spa, the output volume and pressure of said pumps being sieplessly controllable over a wide range by varying the frequency and voltage supplied to the pump drive motors. • Heater units in conduits employed to distribute water and air flows; » Control panels at each seating position incorporating controls to initiate water flow to said discrete groups of water jets, to control the energy of discharge of water from said jets, to control the temperature of said water jet discharge, to control the degree of aeration of said water jets, to control the temperature of said water jet aeration air, and to control the operation of lighting provisions of said spa; • Sensors in said water conduits generating signals indicative of water temperature, water pressure and water flow; • Sensors in said air conduits generating signals indicative of air temperature and air pressure; • A microprocessor-based control unit which, in response to signals from said means to detect occupancy of a seating position, said control pane! selections, and said sensors generating signals indicative of water temperature, water pressure, water flow, air temperature and air pressure controls the flow of water and air to said seating position jets, controls said heater units to regulate air and water temperatures and controls the operation of said pumps to regulate water pressure and flow rates for the purpose of complying with said control panel selections;

2. The system of Claim 1 incorporating a separate, low volume, continuous flow water circulation system incorporating filtration and sterilisation and means and optional heating means.

3. The system of Claim 2 in which the water flow through said continuous flow water circulation system is the sole flow when said spa is unoccupied and is in the range 40 to 250 litres per minute.

4. The system of Claim 1 in which the increased water flow when said spa is occupied bypasses said continuous flow water circulation system and is delivered directly to the occupied said seating positions.

5. The system of Claim 4 in which the bypassing of said continuous water flow system is achieved by means of a solenoid diversion valve controlled by said control unit or by means of a mechanical diversion valve in which the increased water pressure acts to deflect spring valving leaves to close off flow paths.

6. T he system of Claim 1 in which said remotely controllable valves to interrupt or restrict the flow of water to each said seating position and to groups of water jets within each said seating position are solenoid valves controlled by said control unit.

7. The system of Claim 1 in which said water and air heating units are electrically powered resistance heaters controlled by said control unit.

8. The system of Claim 1 in which said means to detect occupancy of a seating position take the form of pressure pads incorporated into the surface of said seating position or light-dark sensors, force sensing resistors, piezo film sensors or the like.

9. The system of Claim 1 in which said water pumps take the form of variable speed centrifugal pumps each driven by an electric motor, the speed of which is steplesslv controlled over a large range through the variation by said control unit of the frequency and voltage applied to said motor.

10. The system of Claim 9 in which, dependent upon the capacity of a said pump, the water flow' is varied between 40 and 1,400 litres per minute.

11. The system of Claim 1 in which the most economical energy consumption is achieved by employing a smaller pump having a flow capacity in the range 40 to 250 litres per minute in conjunction with a larger pump having a flow' capacity in the range 150 to 1,400 litres per minute, said larger pump operating only at times of high flow demand.

12. The system of Claim 1 in which a single pump having a flow capacity in the range 150 to 1,400 litres per minute is employed.

13. The system of Claim 1 in which said control unit runs a stored program covering ai! possible configurations and combinations of occupied seating position, water nozzle combinations, water jet energy, water temperature, air temperature and degree of water aeration.

14. The system of Claim 13 in which said control unit running said stored program, continuously refers to a iook-up table to determine the operating parameters for any possible number of occupied seating positions and their selected configurations in relation to signals received from said pressure, temperature and flow sensors.