Abstract:
A snow sports apparatus ( 10 ) including: a hollow housing ( 12 ) having an internal generally cylindrical surface ( 12 ) and supported, with its axis having a major horizontal component, for rotation about said axis; and means ( 60 ) to provide on said internal generally cylindrical surface ( 30 ), a surface that, as the housing ( 12 ) is rotated, is relatively traversable downwardly on skis or a snowboard on the initial rising part ( 115 ) of the surface&#39;s travel.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates generally to snow sports and in particular is focused on providing an artificial snow sports environment, especially an environment in which participants can gain an extreme experience. 
       BACKGROUND OF THE INVENTION 
       [0002]    The ever increasing demand for snow sports, particularly downhill skiing and snowboarding, is in turn generating an expectation of varied experiences and environments in which enthusiasts can enjoy their sport. For many city dwellers, significant travel may be required to reach a destination where skiing or snowboarding of adequate skill level and excitement can be obtained, and in many locations seasons seem to be shortening, which some attribute to climate change. 
         [0003]    To cater for these demands and expectations, a number of artificial skiing environments have been opened up. In the resort areas themselves, elaborate snowmaking facilities can now carpet areas of slope with artificially created snow drawn from large water reservoirs created for the purpose. Nearer to the homes of the skiing enthusiasts, a variety of indoor venues with artificial slopes have appeared. Artificial snowmaking facilities at the resorts are dependent on the right atmospheric conditions, and do not usually lend themselves to being provided in more skilled and demanding areas, while indoor slope facilities are generally more suited to beginners and family groups than to those seeking more action and thrills from their skiing experience. 
         [0004]    One proposal for an artificial skiing experience, which has not been practically realised, is a large inclined annular surface that revolves in its own plane and on which an artificial skiing surface is provided. 
         [0005]    It is an object of the invention to provide a snow sports apparatus that is capable of providing an exciting and/or physically demanding skiing or snowboarding experience. 
         [0006]    Reference to any prior art in the specification is not, and should not be taken as, an acknowledgment or any form of suggestion that this prior art forms part of the common general knowledge in Australia or any other jurisdiction or that this prior art could reasonably be expected to be ascertained, understood and regarded as relevant by a person skilled in the art. 
       SUMMARY OF THE INVENTION 
       [0007]    The basic concept of the invention is a large revolving housing, for example in the form of a large drum or barrel, coated internally with a skiable surface, preferably comprised of artificially created ice crystals. 
         [0008]    The invention provides snow sports apparatus including:
       a hollow housing having an internal generally cylindrical surface and supported, with its axis having a major horizontal component, for rotation about said axis; and   means to provide on said internal generally cylindrical surface, a surface that, as the housing is rotated, is relatively traversable downwardly on skis or a snowboard on the initial rising part of the surface&#39;s travel.       
 
         [0011]    Advantageously, said means to provide a surface comprises means to deposit a layer of ice crystals that, as the housing is rotated, is relatively traversable downwardly on skis or a snowboard on the initial rising part of the layer&#39;s travel. 
         [0012]    Alternatively or additionally, said means to provide a surface may comprise a solid layer. The solid layer may comprise an array of tiles, for example of an artificial skiable material. Suitable tiles for this purpose are nylon bristled tiles, which may conveniently be of hexagon shape. 
         [0013]    The means to deposit a layer of ice crystals preferably comprises a network of heat conductive tubes on or adjacent said internal generally cylindrical surface, a manifold arrangement for delivering a refrigerant to said tubes at a temperature sufficient to freeze water that contacts the tubes, and means to spray water into the interior of the hollow housing. The spray means may be positionable at or close to the aforementioned axis of the hollow housing, and is preferably withdrawable from this position when one or more individuals are within the housing traversing the layer of ice crystals on skis or snowboards. When in position, the spray means advantageously extends substantially the length of the housing. The spray means is preferably adapted to generate the water spray as a fine mist. 
         [0014]    The apparatus may further include a water chiller for chilling water fed to the spray means, for example to a temperature above the freezing point of water but below 5° C. 
         [0015]    Means is preferably provided to collect and reuse liquid water that collects in or falls away from the hollow housing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The invention will be further described, by way of example only, with reference to the accompanying drawings, in which: 
           [0017]      FIG. 1  is a schematic side elevation of snow sports apparatus according to an embodiment of the invention; 
           [0018]      FIG. 2  is a front elevation of the apparatus depicted in  FIG. 1 ; 
           [0019]      FIG. 3  is a diagrammatic cutaway view showing the refrigerant plumbing configuration; 
           [0020]      FIG. 4  is a cross-section on the line  4 - 4  in  FIG. 1 ; 
           [0021]      FIGS. 5 and 6  are respectively a plan view and a rear elevation of similar apparatus with the external plumbing circuit in a different configuration; 
           [0022]      FIG. 7  is a detail cross-section of a component of the apparatus; and 
           [0023]      FIG. 8  diagrammatically depicts the apparatus in use. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0024]    The illustrated apparatus  10  includes a hollow housing in the form of a large, generally cylindrical barrel  12  with a pair of continuous peripheral steel rings  14  by which it is drivingly supported on two spaced pairs of rollers  16 . Barrel  12  is a large scale housing having a diameter of at least 10 metres and perhaps 25 or 30 metres. Rings  14  are of I-section and rollers  16  have an appropriate structure to guide the rings. One or more of rollers  16  are selectively driven by a motor unit  18  whereby the barrel can be set into rotation about its central axis by fictional driving engagement between rollers  16  and rings  14 . Rollers  16  are mounted on a base structure  20  of suitably dimensioned channel section steel beams  22 . 
         [0025]    Instead of the depicted roller drive, the barrel may instead be mounted on and driven by a central axle arrangement, for example similar to a ferris wheel. 
         [0026]    Barrel  12 , which is made up of an array of suitably formed and interconnected steel plates, has an internal generally cylindrical surface  30 . Extending over substantially the whole of this surface is a uniform network of heat conductive tubing  32 , e.g. of copper. As will be described, this tubing is fed with a selected suitably chilled refrigerant such that the tubes  32  will freeze any water that contacts them. The plumbing configuration is shown in more detail in  FIG. 3 : large manifold pipes  34 , 35  extend longitudinally of the barrel surface at diametrically opposite locations, and are interconnected about each half of the barrel by an array of close spaced semi-circular tube sections  36 . 
         [0027]    The rear end of barrel  12  is closed by an end wall  24 . On the outside of this end wall  24  is mounted a rotary device  40  by which refrigerant is delivered to manifold pipe  34  from a supply pipe  42 , and returned from manifold pipe  35  to a horizontally extending pipe  44  via respective radial conduit segments  34   a , 35   a . The refrigerant circuit is completed by an upstanding header pipe  50  to which pipe  44  delivers the returning refrigerant, a pump  52  and a chiller unit  54  coupled to supply pipe  42 . 
         [0028]    Rotary device  40  will now be further described with reference to  FIG. 7 . An inner rotor component  45  has a flange  46  at one end by which it is concentrically fixed to the end wall  24 . Rotor component  45  is journalled, in spaced bearings  45   a , within an outer annular and hollow pedestal component  47 . The interior of rotor component  45  has a co-axial central duct  48  that communicates at its inner end with outflow conduit segment  35   a  and at its outer end with pipe  44  via a suitable sealed rotary coupling (not shown). The surrounding annular chamber  49  within rotor component  45  is in fluid flow communication at its inner end with inflow conduit segment  34   a , and, via an array of holes  80 , 82  in the outer cylindrical wall  49   a  of component  45  and in the facing inner wall of component  47 , with the internal annular chamber  84  of pedestal component  47 . The latter is coupled to supply pipe  42  and the unit includes suitable seals and packing such as  85 . As the barrel rotates, refrigerant flows (as indicated by arrows  90 ) from supply pipe  42  to return pipe  44  via chamber  82 , holes  82 , 80 , chamber  49 , conduit segment  35   a , manifold pipe  34 , tube sections  36 , manifold pipe  35 , conduit segment  35   a  and duct  48 . 
         [0029]    The front of barrel  12  is partially closed by an annular end wall  25 . A central opening  26  in this end wall serves two purposes: access for an axially disposed spray unit  60 , or access for people to enter the interior of the barrel to enjoy a snow sports experience, as will be further described. 
         [0030]    Referring to  FIGS. 3 and 4  in particular, spray unit  60  comprises an elongate cantilevered pipe  62  with multiple spaced mister spray heads  64  to which water is delivered by pipe  62  from an external supply via a chiller unit (not shown). The chiller unit reduces the temperature of the water to a value above freezing but preferably less than 5° C., for example about 2° C. This chilled water is misted from spray heads  64  to form a cloud of descending mist, as depicted at  70  in  FIG. 4 . The mist particles descend into contact with refrigerant tube sections  36 , whereupon they are transformed to ice crystals. Over an extended period, typically several hours, with chilled water continuously delivered to spray heads  64  and chilled refrigerant continuously circulated through tube sections  36 , while the barrel is continuously and evenly rotated, a layer of ice crystals, i.e. artificial snow, is deposited on and built up about the network of tube sections  36  over the internal surface  30  of the barrel. 
         [0031]    When the artificial snow surface is considered ready for use, the spray unit  60  is withdrawn and moved aside, and one or more individuals  100  can enter the barrel ( FIG. 8 ) through opening  26  on skis or snowboards  110 . If rotation of the barrel is maintained (arrow  92 ), these individuals  100  can relatively traverse the layer of artificial snow downwardly on skis or snowboards  110  on the initial rising part  115  of the travel of the artificial snow layer, as shown in  FIG. 8 . The speed of rotation of the barrel can be adjusted to vary the interests and the skill of the individuals within the barrel: at higher speeds, it is believed that the experience is one that would be relished by so-called “extreme” skiers and snowboarders. 
         [0032]    It may be desirable to close over the opening  26  during build-up of the artificial snow, and/or while a skier or snowboarder is in the barrel, or to optimise the environment within the barrel and/or to reduce interaction between the environment within the barrel and the external environment. 
         [0033]    A suitable refrigerant for circulation within tube sections  36  is ethylene glycol. All the plumbing is preferably steel, apart from tube sections  36  which may be steel but may also typically be copper. 
         [0034]    As earlier indicated, instead of forming a layer of ice crystals on artificial snow, the skiable surface may be provided by a solid layer, e.g. comprised of an array of tiles, for example of an artificial skiable material. Suitable tiles for this purpose are nylon bristled tiles, which may conveniently be of hexagon shape. 
         [0035]    It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.