AU2004210504B1 - Air conditioning system & method - Google Patents

Description

IP Atr i

A

Air Conditioning System Method Field of Invention The present invention relates to air-conditioning systems and apparatus.

Background to the Invention Air-conditioning is one of the most useful inventions in the world. It creates indoor atmospheres of comfortable temperature when the outdoor temperature is uncomfortable. For instance, air-conditioning lowers the indoor air temperature of a building when it is hot outdoors. Air-conditioning can also raise the indoor temperature when it cold outside, often known as "heating".

Air-conditioned atmospheres are largely contained by walls of buildings or other physical structures. The physical structure is needed to prevent the cold or airconditioned air from escaping.

Even with the benefits of indoor air-conditioning in hot climates, the fact is that people need or want to spend lengthy periods outdoors in the heat, typically in summer. For example, sitting in the sun during outdoor sporting events, sitting in outdoor cafes, garden parties, outdoor weddings and outdoor social functions, to name but a few of the numerous instances.

To provide air-conditioning in these outdoor areas, the air-conditioned atmosphere is often contained by some type of physical cover, such as flexible or fabric-walls, for example, canvas or awning. For example, air-conditioned tents are used to provide an air-conditioned area. Nevertheless, the physical structure of the tent spoils the effect of being outdoors, e.g. open sky, sunshine, unrestricted outdoor views. This is because the tent, or other physical cover that is used outdoors effectively creates an indoor environment within the tent, for instance. Even when the tent has transparent walls, that is really not the same as standing under the open sky in the sunshine.

In the prior art, moving air curtains are known, and these are used to act as barriers to keep air-conditioned environments within buildings from escaping mainly through doors. Such moving-air curtains are used in buildings where people are constantly moving through the doors, such as in the wide doorways of department store entrances. These air curtains retain the air-conditioned atmosphere inside the building. These air curtains, however, are not used in the prior art to address outdoor issues, and the focus in the prior art is on retaining the air-conditioned environment inside a building.

An object of the present invention is to provide a system of air-conditioning for an outdoor area which overcomes or ameliorates one or more of the problems in the prior art, or to provide an improved alternative to the prior art.

Summary of Invention According to a first aspect of the present invention, an outdoor airconditioning system adapted to air-condition an outdoor volumetric area, including: air-condition-generating-means able to create an air-conditioned atmosphere in an outdoor area, and air-current-boundary-creation-means adapted to create a boundary of moving air that retains at least a substantial part of the air-conditioned atmosphere in the outdoor volumetric area within the boundary, wherein the air-current-boundary-creation-means is provided with mistcreation-means so that the boundary of moving air is mist-laden.

The air-condition-generating means may include said mist-creation-means, and the boundary of moving air, that is mist-laden, may contribute to the creation of the air-conditioned atmosphere.

Alternatively, the air-condition-generating means may consist of said mistcreation-means, and the boundary of moving air, that is mist-laden, may create the airconditioned atmosphere.

The mist may comprise water which is chilled before entering the moving air.

The boundary of moving air may include a moving-air-ceiling that moves across the outdoor area above standing-height which minimises the air-conditioned atmosphere leaving the outdoor area generally in an upward direction.

The moving-air-ceiling may be generally parallel to the ground.

Alternatively, the moving-air-ceiling may be at an angle to the ground.

The boundary of moving air may include a moving-air-wall which minimises the air-conditioned atmosphere leaving the outdoor area generally in a side-ways direction.

The moving-air-wall may move generally transverse to the moving-air-ceiling.

The air-current-boundary creation means may include an air-current-diverter which diverts air flowing in the moving-air-ceiling into the flow of the moving-airwall.

The moving-air-wall may be generally upright.

The boundary of moving air may include an upright moving-air portion.

The boundary of moving air may also include a transverse moving-air portion that is transverse to the upright moving-air portion.

The boundary of moving air may include a moving-air portion that moves across the ground above standing-head level.

Preferably, the boundary of moving air includes an upright moving-air portion that act as an upright barrier, and a transverse moving-air portion that acts as a transverse barrier, the upright and transverse portions adapted to combine to enable the boundary of moving air to act substantially as a volumetric area that retains at least a substantial part of the air-conditioned atmosphere therewithin.

The air-current-boundary-creation-means may include an air-current-diverter which diverts air flowing in the transverse moving-air portion into the flow of the upright moving-air portion.

The air-current-boundary-creation-means may have air-direction-controllingmeans.

The air-direction-controlling-means may include air-shaping-means adapted to create the boundary of moving air in a layer-like form.

The air-current-boundary creation means may include air-current-generationsmeans.

The air-condition-generating-means may produce either a heating or cooling effect.

The air-condition-generating-means may cause the boundary of moving air to comprise air-conditioned air.

The air-condition-generating-means may create air-conditioned air in the outdoor area within the boundary of moving air.

According to a second aspect of the present invention, there is provided a method of air-conditioning an outdoor volumetric area including the steps of: using an outdoor air-conditioning system to create a boundary of moving air that retains at least a substantial part of the air-conditioned atmosphere in the outdoor area within the boundary, the system being described above.

According to a third aspect of the present invention, there is provided a method of air-conditioning an outdoor area including the steps of: using air-condition-generating-means to create an air-conditioned atmosphere in an outdoor area within the boundary, and using air-current-boundary-creation-means to create a boundary of moving air that retains at least a substantial part of the air-conditioned atmosphere in the outdoor volumetric area, and providing the air-current-boundary-creation-means with mist-creation means which adds moisture to cause the boundary of moving air to be mist-laden.

In the method, the air-condition-generating means may include said mistcreation-means, and the boundary of moving air, that is mist-laden, may contribute to the creation of the air-conditioned atmosphere.

The air-condition-generating means may consist of said mist-creation-means, and the boundary of moving air, that is mist-laden, may create the airconditioned atmosphere.

The mist may comprise water which is chilled before entering the moving air.

According to a fourth aspect of the present invention, there is provided an aircurrent-boundary creation apparatus adapted to create a boundary of moving air that retains within the boundary in an outdoor volumetric area at least a substantial part of an air-conditioned atmosphere generated by air-condition generating means, wherein the apparatus includes mist-creation means so that the boundary of moving air is mistladen.

In the apparatus, the air-condition-generating means may include said mistcreation-means, and the boundary of moving air, that is mist-laden, may contribute to the creation of the air-conditioned atmosphere.

The air-condition-generating means may consist of said mist-creation-means, and the boundary of moving air, that is mist-laden, may create the airconditioned atmosphere.

The mist may comprise water which is chilled before entering the moving air.

The apparatus may include means for creating in the boundary of moving air a moving-air-ceiling that moves across the outdoor area above standing-height which minimises the air-conditioned atmosphere leaving the outdoor area generally in an upward direction.

The apparatus may include an upright channel apparatus wherein airconditioned air from the air-condition generating means is fed into the channel apparatus at a lower end and leaves at another end thereof through air-directioncontrolling-means that re-directs the air to form said moving-air-ceiling.

The air-direction-controlling-means may include an outlet passage that progressively narrows so as to increase the speed of exit of the air.

The air-direction-controlling-means may include an outlet passage that produces a flat planar air stream as the air exits the outlet passage so as to form said moving-air-ceiling.

The apparatus may include means for creating in the boundary of moving air a moving-air-wall which minimises the air-conditioned atmosphere from leaving the outdoor area generally in a side-ways direction.

The air-current-boundary-creation-apparatus may include an air-currentdiverter which diverts air flowing in the moving-air-ceiling into the flow of the moving-air-wall.

The present invention enables people to enjoy the outdoors, e.g. being under an open sky, in the sunshine, with unrestricted outdoor views and without physical walls or windows, while at the same time having the comfort of an air-conditioned environment.

Drawings In order that the present invention might be more fully understood, embodiments of the invention will be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a side-view of a first embodiment of an outdoor air-conditioning system which, in the example, uses an air-current boundary to retain an airconditioned atmosphere in an outdoor area of a street-side cafe; Figure 2 shows a plan view of the embodiment of Figure 1; Figure 3 is a side cross-sectional view of an embodiment of an air-blower that generates the air-flow for the air-current boundary of Figure 1; Figure 4 shows a second embodiment of an outdoor air-conditioning system in which the air-blower is mounted in a stand; Figure 5 shows a plan view of the embodiment of Figure 4; Figure 6A shows details of an embodiment of an air-blower is mounted at the top of a stand in Figures 4 and Figure 6B shows a modification of Figure 6A, in which the air-blower is adapted to be suspended from above; Figure 6C shows the embodiment of Figure 6A in use.

Figure 6D shows the embodiment of Figure 6B in use.

Figure 7 is a side-view of a modification of Figure 1 in which only an upright portion of the air-boundary is used for one side of the open area, since the open area is provided with a solid, physical roof; Figure 8 is a side-view of a further modification of Figure 1 wherein a portion of the air-current boundary is created by a blower located at ground level which blows an air current upwards; Figure 9 shows a further embodiment of an outdoor air-conditioning system in which the liquid mist is introduced into the sheet of air, rather than close to the airblower; and Figure 10 shows a schematic flow diagram of an embodiment of a mistgeneration process for creating the mist used in the embodiments above.

In the various different embodiments, like elements are labelled with like reference numerals merely to assist the reader in understanding the concepts, and are not intended to imply that the elements in each embodiment are identical.

Description of Embodiments Referring to the accompanying drawings, Figure 1 shows a first embodiment of an outdoor air-conditioning system including its components. The system is adapted to air-condition an outdoor volumetric area 200.

Figure 1 shows an example of such an outdoor area 200 that is beside a tall physical structure, such as a building 10. This setting is similar to outdoor cafes, for instance, which are often located in the open air besides buildings. Hence, Figure 1 could be an air-conditioned street-side cafe.

The system of Figure 1 includes air-condition-generating-means in the form of an air-conditioning unit 20. The air-conditioning unit 20 sends a stream 21 of cold air into the outdoor area 200. (The stream 21 of cold air is represented in the diagram by arrows 21). The cold air 21 creates an air-conditioned atmosphere in the outdoor area 200.

Overall Concept Before describing the system in Figure 1 in detail, the overall concept involves the creation of an air-current boundary that is formed from currents of air.

The essential concept is that this air-current boundary is a three-dimensional form, create from air currents. The air-current boundary retains the cold air generally within the volumetric outdoor area 200 that is inside the boundary.

For instance, Figure 1 is an example of an outdoor street cafe that is airconditioned. Since the air-current boundary is invisible, it enables people 30 in the cafe to enjoy the outdoors--open sky, full sunshine, unrestricted outdoor viewswhile, at the same time enjoying the comfort of an air-conditioned environment in the street-side cafe area 200 that is cooler than ambient temperature 210. The people can sit in the sunshine while dining, and still be cooled by the air-conditioned atmosphere inside the invisible air-current boundary, even on a cloudless, hot summer day.

It is understood that an air-current-boundary will let a significant percentage of the air-conditioned atmosphere escape the outdoor area 200. Some degree of escape is inevitable, since there is no solid, physical barrier in the form of solid walls to retain the air-conditioned atmosphere. However, as a compromise that enables the benefits of being outdoors, the air-current boundary slows the escape of the air-conditionedatmosphere from the outdoor area 200, to such an extent that the air-conditioning unit 20 is able to create a sustainable atmosphere in the area 200 which is far more comfortable than ambient temperature.

Air Barrier In Figure 1, the air-current boundary is in the form of a moving-air-barrier 100 (including 100H, 100 The air barrier 100 is made up of one or more air-currents or streams of moving air 100H, 100V, represented by arrows in the diagram. (Suffix H represents generally horizontal, and suffix V represents generally vertical or generally upright).

This air-barrier 100, 100H, 100V acts as a moving-air boundary that defines the external boundary of the volumetric area 200. In Figure 1, the area 200 is the outdoors area beside the building In Figure 1, this moving air-barrier 100 acts as an enclosure that effectively retains, within the outdoor volumetric area 200, at least a substantial part of an airconditioned atmosphere that is being continuously generated by the air-conditioning unit Figure 2 shows a plan view of the embodiment of Figure 1, from which it is clear that the moving air-barrier 100 is in the form of a sheet or layer of moving air.

The intention of the air-barrier 100 is to create one or more walls, made of movingair, which combine to act as an air-current boundary that retains at least a substantial part of the air-conditioned atmosphere in the outdoor area within the boundary.

The invention in its broadest aspect is not limited to any particular shape of air-current boundary used to define a boundary for an outdoor area, since the shape will be influenced by the context of the use.

For example, in Figure 1, the moving-air boundary 100 includes a moving-airceiling in the form of ceiling-boundary 100H. This ceiling-boundary 100H moves across the outdoor area 200 above standing-height, so that the people 30 can stand in the area 200 without their heads intruding into the air stream of the ceiling-boundary 100H. The ceiling-boundary 100H minimises the air-conditioned atmosphere leaving the outdoor area 200 generally in an upward direction.

In this embodiment of Figure 1, the movement of air in the ceiling-boundary 100H is generally parallel to the ground. In other modifications, the air currents in the moving-air-ceiling can be at an angle with respect to the ground.

In Figure 1, the moving-air boundary 100 also includes a moving-air-wall in the form of wall-boundary 100 V. The moving air-current in the wall 1 00V minimises the air-conditioned atmosphere leaving the outdoor area 200 generally in a side-ways direction.

In Figure 1, the wall-boundary 100 V is vertical and generally upright. In other modifications, the wall-boundary 1 00V can be slanted.

In Figure 1, the moving-air-barrier 100 includes a plurality of discrete segments, namely the upper and side walls 100H, 1 00V, however, in other modifications, the air-current boundary may consist of one sheet or layer of moving air that is inclined or angled with respect to the ground, like the inclined side wall of a conventional triangular camping tent.

In Figure 7, which is a variation of Figure 1, where there is already a physical, solid roof extending over the side-walk over where the people are seated, the movingair-barrier 100 can simply consist of an upright wall-boundary 100V. In such a case, the roof 11 over the side-walk prevents the air-conditioned atmosphere leaving the area in the vertical direction, while the vertical wall-boundary 1 00V minimises sideways escape of cold air.

Creating the Air Barrier i) Creating the Air Barrier The outdoor air-conditioning system of Figure 1 is provided with air-currentboundary-creation-means that creates the moving-air-barrier 100.

In Figure 1, the air-current-boundary-creation-means includes air-currentgenerations-means in the form of an air-blower 110. This air-blower 110 is seen in cross-sectional side view in Figure 3. The air-blower 110 has a fan 120 which generates the current of air that makes up the moving-air-barrier 100.

In the embodiment of Figure 1, the piece of equipment 110 that creates the moving-air-barrier 100 is separate from the air-conditioning unit 20 that creates the cold air. Hence, in Figure 1, the moving-air-barrier 100 does not consist of airconditioned air, and would be at ambient temperature.

However, in other modifications (described later in Figure the apparatus that creates the moving-air-barrier 100 can also include an air-conditioner, so that the air-current is cold. This would avoid the need to have an air-conditioning unit 20 that is separate to the apparatus that creates the moving-air-barrier 100.

ii) Shaping the Air Current As mentioned, in Figures 1 and 2, the ceiling-boundary 100H is in the form of a sheet or layer of moving air.

To create this layer-like air current, the air-current-boundary-creation-means is provided with air-direction-controlling-means which includes air-shaping-means. The air-shaping means is adapted to create the boundary of moving air in a layer-like form.

In Figure 3, the air-shaping-means includes a pair of plates 130. The current of air 100H, which originates from the fan 120, passes between the pair of plates 130.

This causes the current of air 100H to generally flow out from between the plates 130 in the form of a flat sheet or layer of moving air 21, shown in Figures 1 and 2.

As the sheet or layer of air gets further away from the plates 130, it tends to spread outwards, and hence the layer of air tends to resemble a slightly-expanding wedge of air.

This flat current of layer-like air 100H acts as an air-current boundary minimises the loss of cold air from the outdoor area 200 in an upward direction.

In Figure 3, each of the plates 130 are flat and tapered towards the exit-end of the plates where the air exits. The tapering causes an increase in speed as the air exits from between the plates.

In modifications of the air-shaping-means, it must be remembered that shaping of the air stream into a generally flat layer can be achieved with a variety of apparatus configurations, different to the flat plates of Figure 3. For instance, the inner surface of the plates are preferably smooth but can be textured or corrugated. The plates can also be parallel. There can be two or more plates, for instance, five or six plates. In other words, preferred embodiments of the invention are not limited to air-shapingmeans of a particular shape or configuration, provided that the air, which exits from the air-shaping-means, travels in the form of a flat sheet-like or layer-like stream of air.

Air Current Diverters In Figure 1, the air of the wall-boundary 100V moves generally transverse to the current of air in the ceiling-boundary 1 00H.

In some modified embodiments, each discrete segment 100 H, 100 V of the airstream may each be created by a separate air-blower. However, in Figure 1, both segments 100 H, 100 V of the moving-air-barrier 100 are actually the same flow of air, which has been diverted in direction.

To achieve the air diversion, in Figures 1 and 2, the air-current-boundary creation means also includes an air-current-diverter in the form of angle-diverter 400.

In the example of Figure 1A, the diverter 400 is approximately 4 meters from the building The angle-diverter 400 diverts air, flowing in the ceiling-boundary 100H, into the flow of the wall-boundary 100V. Thus, the air current in the two segments 100H,.

100V are the same stream of air, except that the direction has been diverted by the angle-diverter 400.

Although, in Figure 1, it appears in the drawing that the angle-diverter 400 is suspended in air, in the embodiment it is actually supported by some physical support such as a pole or strut (not shown). The embodiment is not limited to any type of support.

Mist-laden Air Streams In the embodiment of Figure 1, the air of the moving-air-barrier 100 is mistladen.

To achieve this, the air-current-boundary-creation-means is provided with mist-creation-means. In Figure 3, one or more mist-nozzles 140 introduce fine moisture droplets into the stream of air within the air-blower 110. The moisture droplets are extremely small to allow the moving-air-barrier 100 to have an ultra-fine mist.

The presence of the mist in the air flow of the moving-air-barrier 100 enhances the ability of the air-current boundary to retain a substantial part of an air-conditioned atmosphere, sufficient to create a discernible increase in comfort level of the people present in the outdoor area 200, compared to ambient temperature.

Without being limited by theory, it is postulated that the mist-laden moving air-barrier is effective, because it presents a barrier that has a different phase or state, compared to the environment both inside and outside the air-barrier 100.

In embodiments where the air-barrier is not mist-laden, the ambient atmosphere outside the barrier is gaseous air, the barrier would be gaseous air, and within the area 200 is likewise filled with gaseous air. In other words, all three parts are of the same phase or state. Therefore, there is no change in state between the outside, the barrier, and the inside. Hence, air from within the area 200 could more readily traverse the moving-air-barrier 100.

In contrast, in embodiments where the moving-air-barrier is mist-laden, there is a change in state. The moving-air-barrier 100 contains a liquid state in the form of an ultra-fine mist of water particles. Without being bound by theory, it is postulated that this difference in state hinders, to a degree, the ability of the air inside the area 200 to traverse the moving-air-barrier 100, compared to a mist-free air-barrier.

Figure 10 shows a schematic flow diagram of an example of a process used for creating the mist that is introduced into the air current boundary.

In Figure 10, water enters the mist-creation system through a water inlet 300.

Since tap water may contain a certain amount of particulate, which is undesirable for mist-creation and which could clog the nozzles 140, the incoming water is filtered by a water filter 310.

The ultra-fine water mist that emanates from the nozzles 140 can, for example, include water droplets the size of 10 to 30 microns, hence it is advantageous to filter out particulate matter from the incoming water. (To put this in perspective, microns is equal to around 1/10th of the thickness of a human hair) In the embodiments, the mist is cool so that it can contribute to the lowering of temperature of the outdoor area 200. In hot climates, the water can be chilled by a water chilling apparatus 320 in the form of a refrigeration apparatus.

Without being limited to theory, it is believed that forming the mist from water, that is at a lower temperature than the ambient atmosphere temperature, will help the water droplets to absorb at least a part of the heat in the outdoor area.

In Figure 10, the chilling apparatus 320 may be provided a temperature control system to control the temperature of the water.

Chilled water, coming from the chilling apparatus 320, enters a reservoir area in the form of a reservoir tank 330. The body of liquid, stored in the reservoir tank 330, acts as a reserve from which the system can draw liquid when required. The rate of usage of water in the mist-creation may not correlate with the rate that the chilling apparatus 320 produces chilled water. For instance, at certain times on a very hot day, the overall system may require a higher amount of mist to be created, at a rate that might beyond the output level of the chilling apparatus 320. Hence, drawing water from the chilled reservoir tank 330, rather than directly from the water inlet 300, ensures a greater likelihood of a steady supply of chilled water on all occasions.

When the water is chilled to a suitably low temperature, the chilled water enters a compression pump 340, in which the water is pressurised, for example, to around 1000 to 2000 psi of pressure.

As the water leaves the high pressure water pump 340, it passes through pipes or tubes to reach the nozzles 140, as seen in Figures 10 and 3.

As seen in Figure 3, the nozzles 140 are preferably supplied with water in parallel to enable the pressure in each nozzle 140 to be similar to the other nozzles. In other embodiments, the delivery of water to the nozzles may be in series or in a loop, provided the pressure of water in the loop can be maintained sufficiently high, so that all nozzles receive water at adequate pressure levels to create the spray.

The nozzles 140 include very fine apertures through which the water sprays into the airstream 21. The fineness of the nozzles is a further reason for the need for filtering of the water in the exemplary embodiment.

In Figure 3, after the water mist enters the air stream 21, the ultra-fine droplets of water are carried along in the air stream 21. During this period of travel along with the airstream, the water droplets progressively evaporate, which is believed to contribute to the lowering of the temperature in the outdoor area 200, at least to a certain degree.

Furthermore, the evaporation of the ultra-fine water droplets is believed to also humidify the air in and around outdoor area 200, as well as cool the air. Therefore, to avoid excessive humidity that could cause discomfort to the people 30, the system of the exemplary embodiment is provided with a humidity-level control system that controls the amount of mist in the airstream. When a sensor of the system detects that the humidity in the outdoor area is beyond predetermined limits, the humidity-level control system can cause the amount of water entering the airstream, through the nozzles 140, to decrease. The nozzles, therefore, can be controlled by valves that are actuated by an electronic circuit in the humidity-level control system, which includes a microprocessor.

Alternatively, rather than an interactive humidity-level control system that uses interactive sensors, the amount of liquid used to create the mist can be controlled by a timing mechanism which delivers mist to the airstream based on typical time periods that have been ascertained as being ideal for particular environments.

Furthermore, the temperature of the outdoor area 200 is also controlled by the amount and temperature-level of air-conditioned air that is created by the airconditioning unit 20, and conventional temperature-control systems may be used to monitor the temperature.

Figures 6A and 6B show an air cooling system in which an air-conditioning fan coil element 24 is located inside the housing of the blower. The fan coil element 24 is cooled by refrigeration as part of the air conditioning unit. Thus, in the embodiments of Figures 6A and 6B, the step of air-conditioning the air is achieved at the same location as the step of mist-creation (rather than having a separate airconditioning unit 20 and air blower 110, as in the first embodiment of Figure 1).

Free-standing Embodiment Figure 4 shows a second embodiment which includes a free-standing apparatus. (This is in contrast to the embodiment of Figure 1 where some of equipment was mounted on a nearby physical structure The system of Figure 4 includes an air-conditioning unit 20. The airconditioning unit 20 sends the stream 21 of cold air (represented in the diagram by arrows 21) into the outdoor area 200. The cold air 21, generated by the airconditioning unit 20, creates an air-conditioned atmosphere in the outdoor area 200.

Unlike the embodiment of Figure 1, in the embodiment of Figure 4 the airconditioning unit 20 is combined with the air-blowing apparatus 110 that creates the current of air that forms the air-current boundary. This means that the air-conditiongenerating-means causes the moving-air-barrier 100 to be air-conditioned. Thus, in Figure 4, the moving-air-barrier 100, 1 00H, 100 V is cold.

In other words, in the second embodiment in Figure 4, the moving-air-barrier performs a dual role of, firstly, providing the air-conditioned coolness and, secondly, acting as a barrier which keeps that coolness substantially inside the outdoor area 200.

In Figure 4, the cold, moving-air-barrier 100 is made up of one or more aircurrents or streams of moving air 100H, 100 V, represented by arrows in the diagram.

(Suffix H represents generally horizontal, and suffix V represents generally vertical).

Thus, in Figure 4, the boundary of moving air includes an upright moving-air portion 100V, and also includes a transverse moving-air portion 100H that is transverse to the upright moving-air portion. The transverse portion 100H moves across the ground above standing-head level, so that the people 30 do not intrude into the moving air when they stand up.

This air-barrier 100, 100H, 100 V acts as a moving-air boundary that defines the boundary of the volumetric area 200. In Figure 4, the area 200 is an outdoor area which could be in the middle of a garden, for example.

In Figure 4, this moving air-barrier 100, 1 00V, 100 H acts as an enclosure that effectively retains, within the outdoor volumetric area 200, at least a substantial part of an air-conditioned atmosphere that is being continuously generated by the airconditioning unit In Figure 4, angle-diverters 400 are used to change the direction of the horizontal stream 100H into a vertical stream 100V. The angle-diverters 400 are supported on some for of support such as a post (not shown).

In Figure 4, the cold air that is generated by the air-conditioning unit 20 is caused by a pair of plates 130 to spread into a flat plate-like layer 100 H.

The plates 130 are mounted on a stand 40. The air-conditioning unit 20 and the of air-blowing apparatus 110 are housed inside the stand The plates 130 define an air-channel exit that has a tapered exit, so that air rushing out from the plates has to exit through a narrowed end-exit. This causes the velocity of the air to either increase or at least not slow down.

Figure 5 shows a plan view of the embodiment of Figure 4, from which it is seen that the moving air-barrier 100 is in the form of a generally circular, expanding sheet or layer of moving air. The air-barrier 100, 100H, 100V acts as an air-current boundary that retains at least a substantial part of the air-conditioned atmosphere in the outdoor area 200 within the boundary 100.

The outdoor structure of Figure 4 may be covered by an umbrella covering, such as a canvas or tent material, to shield people from direct sunshine, or merely to provide an aesthetic appearance.

Modifications Figure 6A shows a cross-sectional view of an embodiment of an air-blower is mounted on top of the stand 40, as seen in Figure 4. Here the air-blowing apparatus 110 is housed on top of the stand In Figure 6A, the fan 120 blows air, which is directed radially and outwardly by the circular plates 130. One or more mist-nozzles 140 introduce fine moisture droplets into the stream of air within the air-blower 110.

Figure 6B shows a further variation of an air-blower which, in contrast to Figure 6A, is designed to be suspended from above, for example, by a line, tube, cord or cable 40. The air-blower 120 in Figure 6B performs essentially the same as the apparatus in Figure 6A.

Figure 6C shows the embodiment of Figure 6A in use.

Figure 6D shows the embodiment of Figure 6B in use.

Figure 8 shows a modification where the air-current-generations-means includes an air-blower 11 OA that is located at ground level. The ground-level air blower 11 OA blows a sheet of air upwards to form the upright or generally vertical wall-boundary 100V. The configuration in Figure 8 may be required when local government regulations do not permit physical structures, such as the angle-diverter 400 to be constructed close to existing buildings. The modification of Figure 8 achieves roughly the same effect as the embodiment in Figure 1. In Figure 8, the airblower 110 OA is created to have the appearance of a fence.

Figure 9 shows another variation in which one or more mist-nozzles 140 introduce fine moisture droplets into the ceiling-boundary 100 H, rather than being introduced into the air stream inside the blower. In this variation of Figure 9, the blower 110 OA is not provided with the mist-nozzles 140 as in Figure3.

Embodiments of the invention can either have the air-condition-generating.

means producing either a heating or cooling effect.

In Figures 1, 4 and 6A, the air-conditioning units 20 are mounted above the ground on some upstanding structure, however, in other embodiments, an airconditioning unit can also be located at ground level, even amongst the people Some embodiments can have a plurality of small air-conditioners located amongst the people.

It is to be expected that the ability of the air-barrier 100 to retain the airconditioned atmosphere will be far less than compared to solid walls of building. The retention is of such degree as to enable the people 30 inside the air-walled enclosure 100 to enjoy a tangible difference in comfort, compared to ambient temperature. Such a degree would be regarded as a substantial retention for the purposes of this description of embodiments.

For the sake of clarity, in this specification, the word "area", such as the outdoor area 200 in Figure 1, is understood to refer to a three-dimensional volumetric area, and hence the words "area" here does not refer to a flat two-dimension surface area.

Throughout this specification, the reference to horizontal and vertical are understood to be approximate, and do not imply a restriction of having to be precisely 0 degrees and 90 degrees respectively with respect to flat ground. These terms are merely used in a general, broad and purposive sense.

Embodiments of the invention can incorporate air-conditioning that either heats or cools the atmosphere within the outdoor area 200.

In the illustrated embodiments, the air-barrier 100, 100H, 100V is created by one piece of air-blowing apparatus 110, however, in other modifications, each of the segments 100H, 100V might each be created separately by a different piece of equipment, particularly when the outdoor volumetric area 200 is very large. For instance, a large arena can be provided with a large number of air-blowers that together create a moving-air ceiling above the large arena.

In other modified embodiments, it is possible to omit a separate airconditioner apparatus 20, in which case the air-condition-generating-means consists exclusively of the mist in the mist-laden, moving-air-barrier.

In this specification, reference to prior art is not to be taken as an admission of the state of common general knowledge.

The scope of this specification and its appended claims excludes the area of art relating to indoor air-conditioning.

The invention is not limited to the examples given of cafes and garden gazebos in the embodiments, but can be used for all manner of occasions where people gather in an outdoor area, such as outdoor weddings, parties, meetings etc.

The embodiments have been described by way of example only, and modifications are possible within the scope of the invention as defined by the appended claims.

Claims (39)

1. An outdoor air-conditioning system adapted to air-condition an outdoor volumetric area, including: air-condition-generating-means able to create an air-conditioned atmosphere in an outdoor area, and air-current-boundary-creation-means adapted to create a boundary of moving air that retains at least a substantial part of the air-conditioned atmosphere in the outdoor volumetric area within the boundary, wherein the air-current-boundary-creation-means is provided with mist- creation-means so that the boundary of moving air is mist-laden.

2. A system of claim 1 wherein the air-condition-generating means includes said mist-creation-means, and wherein the boundary of moving air, that is mist-laden, contributes to the creation of the air-conditioned atmosphere.

3. A system of claim 1 wherein the air-condition-generating means consists of said mist-creation-means, and wherein the boundary of moving air, that is mist-laden, creates the air- conditioned atmosphere.

4. A system of any one of the preceding claims wherein the mist comprises water which is chilled before entering the moving air.

A system of any one of the preceding claims wherein the boundary of moving air includes a moving-air-ceiling that moves across the outdoor area above standing- height which minimises the air-conditioned atmosphere leaving the outdoor area generally in an upward direction.

6. A system of claim 5 wherein the moving-air-ceiling is generally parallel to the ground.

7. A system of claim 5 wherein the moving-air-ceiling is at an angle to the ground.

8. A system of claim 5 wherein the boundary of moving air includes a moving- air-wall which minimises the air-conditioned atmosphere leaving the outdoor area generally in a side-ways direction.

9. A system of claim 8 wherein the moving-air-wall moves generally transverse to the moving-air-ceiling.

A system of claim 9 wherein the air-current-boundary creation means includes an air-current-diverter which diverts air flowing in the moving-air-ceiling into the flow of the moving-air-wall.

11. A system of any one of claims 8 to 10 wherein the moving-air-wall is generally upright.

12. A system of any one of claims 1 to 4 wherein the boundary of moving air includes an upright moving-air portion.

13. A system of claim 12 wherein the boundary of moving air also includes a transverse moving-air portion that is transverse to the upright moving-air portion.

14. A system of any one of claims 1 to 4 wherein the boundary of moving air includes a moving-air portion that moves across the ground above standing-head level.

A system of any one of claims 1 to 4 wherein the boundary of moving air includes an upright moving-air portion that act as an upright barrier, and a transverse moving-air portion that acts as a transverse barrier, the upright and transverse portions adapted to combine to enable the boundary of moving air to act substantially as a volumetric area that retains at least a substantial part of the air-conditioned atmosphere therewithin.

16. A system of claim 15 wherein the air-current-boundary-creation-means includes an air-current-diverter which diverts air flowing in the transverse moving-air portion into the flow of the upright moving-air portion.

17. A system of any one of the preceding claims wherein the air-current- boundary-creation-means has air-direction-controlling-means.

18. A system of claim 17 wherein the air-direction-controlling-means includes air- shaping-means adapted to create the boundary of moving air in a layer-like form.

19. A system of any one of the preceding claims wherein the air-current-boundary creation means includes air-current-generations-means.

A system of any one of the preceding claims wherein the air-condition- generating-means produces either a heating or cooling effect.

21. A system of any one of claims 1 to 19 wherein the air-condition-generating- means causes the boundary of moving air to comprise air-conditioned air.

22. A system of any one of the preceding claims wherein the air-condition- generating-means creates air-conditioned air in the outdoor area within the boundary of moving air.

23. A method of air-conditioning an outdoor volumetric area including the steps of: using an outdoor air-conditioning system to create a boundary of moving air that retains at least a substantial part of the air-conditioned atmosphere in the outdoor area within the boundary, the system being in accordance with any one of claims 1 to 22.

24. A method of air-conditioning an outdoor area including the steps of: using air-condition-generating-means to create an air-conditioned atmosphere in an outdoor area within the boundary, and using air-current-boundary-creation-means to create a boundary of moving air that retains at least a substantial part of the air-conditioned atmosphere in the outdoor volumetric area, and providing the air-current-boundary-creation-means with mist-creation means which adds moisture to cause the boundary of moving air to be mist-laden.

A method of claim 24 wherein the air-condition-generating means includes said mist-creation-means, and wherein the boundary of moving air, that is mist-laden, contributes to the creation of the air-conditioned atmosphere.

26. A method of claim 24 wherein the air-condition-generating means consists of said mist-creation-means, and wherein the boundary of moving air, that is mist-laden, creates the air- conditioned atmosphere.

27. A method of any one of claims 24 to 26 wherein the mist comprises water which is chilled before entering the moving air.

28. An air-current-boundary creation apparatus adapted to create a boundary of moving air that retains within the boundary in an outdoor volumetric area at least a substantial part of an air-conditioned atmosphere generated by air-condition generating means, wherein the apparatus includes mist-creation means so that the boundary of moving air is mist-laden.

29. An apparatus of claim 28 wherein the air-condition-generating means includes said mist-creation-means, and wherein the boundary of moving air, that is mist-laden, contributes to the creation of the air-conditioned atmosphere.

An apparatus of claim 28 wherein the air-condition-generating means consists of said mist-creation-means, and wherein the boundary of moving air, that is mist-laden, creates the air- conditioned atmosphere.

31. An apparatus of any one of claims 28 to 30 wherein the mist comprises water which is chilled before entering the moving air.

32. Apparatus of any one of claims 28 to 31 including means for creating in the boundary of moving air a moving-air-ceiling that moves across the outdoor area above standing-height which minimises the air-conditioned atmosphere leaving the outdoor area generally in an upward direction.

33. Apparatus of claim 32 including an upright channel apparatus wherein air- conditioned air from the air-condition generating means is fed into the channel apparatus at a lower end and leaves at another end thereof through air-direction- controlling-means that re-directs the air to form said moving-air-ceiling.

34. Apparatus of claim 33 wherein the air-direction-controlling-means includes an outlet passage that progressively narrows so as to increase the speed of exit of the air.

Apparatus of claim 33 wherein the air-direction-controlling-means includes an outlet passage that produces a flat planar air stream as the air exits the outlet passage so as to form said moving-air-ceiling.

36. Apparatus of any one of claims 32 to 35 including means for creating in the boundary of moving air a moving-air-wall which minimises the air-conditioned atmosphere from leaving the outdoor area generally in a side-ways direction.

37. Apparatus of claim 36 wherein the air-current-boundary-creation-apparatus includes an air-current-diverter which diverts air flowing in the moving-air-ceiling into the flow of the moving-air-wall.

38. An outdoor air-conditioning system for an outdoor volumetric area substantially as hereinbefore described and illustrated with reference to the accompanying drawings.

39. A method of air-conditioning an outdoor volumetric area substantially as hereinbefore described and illustrated with reference to the accompanying drawings. An air-current-boundary creation apparatus adapted to create a boundary of moving air that retains at least a substantial part of the air-conditioned atmosphere in an outdoor volumetric area within the boundary, the apparatus substantially as hereinbefore described and illustrated with reference to the accompanying drawings.