Patent Application
20130056546
This invention pertains generally to the art of fluid sprinkling and more particularly to snow making towers for ski slopes.
The present invention pertains to improvements in snow making towers of the type disclosed in U.S. Pat. No. 5,823,427, issued Oct. 20, 1998, for METHOD AND APPARATUS FOR MAKING SNOW. Such snow making towers are generally manufactured of aluminum pipe and extend upwardly at least twenty to thirty feet and have air and water discharge nozzles at the upper end for producing a plume of atomized water from interacting air and water discharged under pressure, either internally or externally mixed, to produce snow in sub-freezing ambient conditions.
It is desirable that the tower be as tall as possible as the high loft produces better quality of snow as the plume is given a greater dwell time to fall in sub-freezing conditions to the ski surface. However, to date, it has only been practical to manufacture snow making towers of aluminum pipe to a approximate length of thirty feet. For example, a forty foot section of aluminum pipe of sufficient diameter is simply far too heavy for suspension at this extreme height above ground. It has also been discovered that welding aluminum pipe sections together of increasing diameter in end-to-end telescopic fashion is not practical as the pipe sections break at the welded connections due to the fact that the towers are inclined or lean outwardly, and also due to ice buildup which can commonly occur at the top of the tower.
A possible solution would be to manufacture an aluminum pipe tower forty feet long or so of a tapered cross section which decreases in diameter as the height of the pipe increases. However, this is extremely expensive to manufacture and is, in fact, extremely impractical to manufacture. Ideally such a tall pipe tower should be manufactured of commonly available aluminum pipe stock.
In addition, it is desirable to manufacture aluminum pipe towers in sections which are no longer than twenty feet for practical shipping.
An additional problem that is incurred with present day snow making towers is that the atomized water plume for creating snow in sub-freezing ambient conditions is ejected from the snow making nozzles at the top of the tower at a velocity which does not adequately project the manufactured snow a sufficient distance away from the tower head. It is therefore desirable to provide a snow making tower system wherein the atomized water plume can be projected outwardly from the tower pipe at a greater distance.
The snow making tower of the present invention includes an elongated upright aluminum tower pipe mounted on a support with air and water connectors at the lower end of the elongated pipe for connection to sources of air and water under pressure and snow making nozzles at the upper end for discharge of air and water under pressure into ambient atmosphere, by either internal or external mixing, for manufacture of snow in sub-freezing conditions. The snow making tower pipe of the present invention is made up of multiple aluminum pipe segments of different diameters dimensioned whereby the pipe segments are telescopically fitted and welded end to end with the segment of largest diameter at the lower end. The end to end weld fittings are angled relative to the longitudinal axis of the tower pipe at an angle which is less than 90 degrees, and typically between 45 degrees to 50 degrees. This provides a much longer weld connection than the typical right angle weld, connection which will hold up to severe conditions, such as ice loading. This permits the snow making tower to be manufactured of light weight aluminum piping at finished length of forty feet or so of commonly available aluminum pipe as off-the-shelf products.
When the tower pipe is supported at an inclined angle as a lean-out tower, the slanted weld fittings are positioned with the upper most point of the weld fittings aligned along the under side of the inclined tower pipe to provide maximum support capabilities at the weld connections.
The tower pipe may consist of two separable sections releasably joined by a pipe coupling. Accordingly, a forty foot tower may be inexpensively shipped in two twenty foot sections and then coupled together in the field. The lower end of the tower pipe, which includes the air and water connectors, is detachable from the remainder of the tower pipe whereby tower pipes of different lengths and different lower end diameters may be interchangeably connected to the lower end of the tower pipe. For this purpose, the lower end of the tower pipe is threadably connected to the remainder of the tower pipe. The bottom end of the remainder of the tower pipe, whether a forty foot tower or a twenty foot tower, is provided with the same diameter threaded connection for interchangeable connection to the lower end of the tower pipe.
In a second embodiment of the present invention, a novel method of manufacturing snow is provided by ejecting air and water under pressure, by either internal or external mixing thereof, through snow making nozzles to form an atomized plume of water in adjacent ambient atmosphere under sub-freezing conditions. The present invention improves the method by ejecting water under pressure in the form of a spray stream at a velocity greater than the ejection velocity of the aforesaid plume and directing this stream to engage the plume and thereby project the plume outwardly farther than possible without the assistance of the spray stream.
In this embodiment a projection water nozzle is positioned on the upper end of the snow tower pipe below the snow making nozzles which create the atomized water plume. The projection water nozzles ejects water under pressure in the form of a spray stream at a velocity which is greater than the ejection velocity of the plume. The projection water nozzle is directed whereby the stream from the projection nozzle is directed upwardly and outwardly to engage the plume and thereby project the plume outwardly from the tower pipe farther than possible without the assistance of spray stream.
The projection nozzle is preferably dimensioned and configured to provide maximum laminar water flow.
It has been further discovered that the snow making nozzle at the top of the tower pipe should include one or multiple sets of three nozzles which are circumferentially positioned and spaced about the pipe tower with a separation of less than 60 degrees and most preferably approximately 30 degrees. It was formally thought that a separation angle of 60 degrees was ultimate, but it has been discovered that better interaction and atomization occurs when the nozzles are separated by an angle which more closely approximates 30 degrees. In addition, this provides a tighter plume for better contact and interaction with the spray stream from the projection water nozzle for more effectively and efficiently projecting the plume outwardly.
Other objects and advantages appear hereinafter in the following description and claims. The accompanying drawings show, for the purpose of exemplification, without limiting the scope of the present invention or the appended claims, certain practical embodiments of the present invention wherein:
Referring to the drawings, the snow making tower 10 of the present invention includes a substantially vertical ground support pole 11 having the bottom end thereof anchored into the ground surface 12. Tower support sleeve 13 is coaxially mounted on ground support pole 11 for support thereon and free axial rotation thereon for a full 360 degrees.
Upwardly extending support arm 16 is pivotally supported intermediate its ends to the upper end of tower support sleeve 13 at pivotal connection 24 for pivotal movement substantially from horizontal to vertical. Elongated snow making tower pipe 18 is provided with snow making nozzles 20 adjacent the upper end of the tower at upper portion 19 and respective water and air connections 22 and 21 are provided at the lower end of tower pipe 18 for connection to remote sources of air and water under pressure through the hoses depicted for supply to the nozzles 20 for ultimate discharge into ambient atmosphere for manufacture of snow in sub-freezing conditions in a known fashion.
Snow making nozzles 20 in this instance consist of four sets 21 of three water nozzles circumferentially positioned and spaced about the pipe tower upright top section 32 and air nozzles 22 with a separation of 30 degrees. The upper set of the three water atomizing nozzles 21 are provided with corresponding higher positioned adjacent air jet nozzles 22. The water snow making nozzles 21 are angled relative to the upper portion 32 of pipe snow making tower 10 at an angle of 45 degrees as indicated at 23.
These water snow making nozzles 21 eject water in the form of a spray as schematically illustrated in
The elongated snow making tower pipe 18 itself is also pivotally secured intermediate its ends to the upper end of support arm 16 at pivotal connection 24 for movement in a vertical plane from parallel alignment with support arm 16 to positions below horizontal so that one may readily access the nozzles 21 from the ground for repair or exchange.
The support arm 16 vertically supports tower pipe 18 at any desirable angle. However, tower pipe 18 is preferably supported at 10 degrees to 30 degrees relative to vertical and most typically is supported at 30 degrees.
Elongated upright tower pipe 18 is constructed of aluminum pipe comprised of pipe segments 25, 26, 27 and 28. Lower pipe segment 25 has a 3 inch internal diameter. Pipe segment 26 has a 2½ inch ID, aluminum pipe segment 27 has a 2 inch ID, and pipe segment 28 has a 1½ inch ID. Each of these pipe segments is approximately ten feet long and they are available on the market as off the shelf items.
The multiple aluminum pipe segments 25, 26, 27 and 28 are telescopically fitted and welded end to end with the segment 25 of largest diameter at the lower end, and the end to end weld fittings are angled as illustrated relative the longitudinal axis of the tower pipe at an angle of less than 90 degrees. In this instance that angle is 45 degrees and is preferably 45 degrees to 50 degrees. The tower pipe 18 is supported at an incline angle as illustrated in
Since the overall length of tower pipe 18 is approximately forty feet, the pipe tower is provided in two sections, an upper section 35 and a lower section 36 coupled together by a threaded coupling sleeve 37.
In typical fashion, the air is supplied to air nozzles 22 by internal aluminum air supply pipe 38 which is insulated and prevented from freezing by the surrounding water supplied through the outer pipe 18.
The snow making tower 10 of the present invention is provided with a projection water nozzle 40 positioned on the upper end of tower pipe 18 below the snow making nozzles 20 for ejecting water under pressure in the form of a spray stream as diagrammatically illustrated in
Projection nozzle 40 is a high velocity high volume nozzle, as opposed to the water atomizing nozzles 21, which may provide maximum laminar water flow, such as laminar flow spray nozzles manufactured by Spraying Systems Co. under the trademark FullJet.
Projection nozzle 40 is angled relative to the upper section 32 of pipe tower 18 at an angle of 30 degrees as indicated at 39. However, projection nozzle 40 may also be angled at an angle of 45 degrees relative to upper pipe section 32 similar to water snow making nozzles 21.
Referring to
As illustrated in
