WO2008114287A1

WO2008114287A1 - Spray head for the production of artificial snow

Info

Publication number: WO2008114287A1
Application number: PCT/IT2007/000194
Authority: WO
Inventors: Marco Pala
Original assignee: WEISSER WOLF Srl
Current assignee: WEISSER WOLF Srl
Priority date: 2007-03-16
Filing date: 2007-03-16
Publication date: 2008-09-25
Anticipated expiration: 2009-09-16

Abstract

A spray head (4) for the production of artificial snow which envisages the use of a shutter (40) capable of activating a stage for water injection using a pressure difference between the air feeding duct (11) and at least one water feeding duct (10). The spray head (4) allows the automatic opening of a stage when the water delivery pressure exceeds a predetermined value.

Description

DESCRIPTION "Spray head for the production of artificial snow"

[0001] The present invention relates to a spray head for the production of artificial snow, and in particular a spray head comprising an improved device for opening and closing the various head stages.

[0002] As is known, spray heads for the production of artificial snow use water and air under pressure. Delivering a small amount of water into a flow of air under pressure creates ice cores, thanks to the sudden air expansion. When such cores come into contact with very fine water drops, they allow the creation of artificial snow. In particular, the spray heads comprise core makers, from which air and water mixed with each other come out in the form of cores, and nozzles from which finely atomised water comes out.

[0003] The cores intercept the very fine particles of atomised water and cause the coalescence thereof, with the consequent forming of artificial snow flakes. [0004] The spray heads usually comprise a plurality of stages, that is, a plurality of nozzles that inject water under pressure. The stage redundancy serves for increasing the production of snow, if the outside temperature conditions allow so. [0005] In other words, if the outside temperature drops further, subsequent stages open to increase the production of snow. The technique of increasing the number of stages is preferred over that of using few stages having nozzles with larger diameter, since nozzles with larger diameters would not ensure sufficient water atomisation, especially during operation at low pressures. In that case the drops formed would be too large and they would not be able to turn into snow. [0006] The spray heads of the prior art therefore envisage the use of a plurality of stages that are fed by water feeding ducts independent of one another. In this way it is possible to open and therefore feed ducts and relevant nozzles separately. [0007] Therefore, this solution is expensive as it envisages the use of as many ducts as the stages or nozzles are. It should be noted that the spray heads are arranged at about 11 metres of height relative to the water feeding trap, so a feeding pipe of about 11 metre length must be used for each stage. Moreover, the distributor must have a dedicated system for opening and managing water pressure for each stage. Therefore, the prior art systems are mechanically complicated and expensive to construct . [0008] The problem of the present invention is to provide a spray head for the production of artificial snow which should solve the disadvantages mentioned with reference to the prior art.

[0009] Such disadvantages are solved with a spray head in accordance with claim 1. [0010] Other embodiments of the spray head according to the invention are described in the subsequent claims .

[0011] Further features and advantages of the present invention will appear more clearly from the following description of a preferred non-limiting embodiment, wherein :

[0012] figure 1 shows a front view of spray head for the production of artificial snow according to an embodiment of the present invention;

[0013] figure 2 shows a section view of the spray head of figure 1, along the section plane II of figure 1;

[0014] figure 3 shows a perspective view of a detail of the spray head of figure 1;

[0015] figure 4A shows a section view of the spray head of figure 1, along the section plane IV of figure 1, in a first operating configuration;

[0016] figure 4B shows a section view of the spray head of figure 1, along the section plane IV of figure 1, in a second operating configuration;

[0017] figure 5 shows a section view of the spray head of figure 1, along the section plane V of figure 4A; [0018] figure 6 shows a section view of the spray head of figure 1, along the section plane VI of figure 4B. [0019] With reference to the above figures, reference numeral 4 generically denotes a spray head for the production of artificial snow.

[0020] Spray head 4 comprises a head body 8 connected for example to a bar for arranging the spray head at a sufficiently high height for radiating a suitable surface of mantle of snow. [0021] The head body 8 extends for example along a prevailing direction Y, substantially parallel to a vertical direction or to a direction of fall of the artificial snow flakes generated. [0022] The head body 8 is closed at the top by a cover 9 and at the bottom it is put in fluid connection with water feeding ducts 10 and with a compressed air feeding duct li.

[0023] The head body 8 has at least one spray wall 12 suitable for spraying air and water for the production of artificial snow.

[0024] At the spray wall 12, head body 8 comprises at least one core maker 16 suitable for generating and spraying cores of artificial flakes. [0025] The head body 8 comprises at least one nozzle 20 suitable for spraying a water jet so as to intercept the cores and favour the growth thereof into snow flakes. [0026] Nozzles 20 are inserted into special spray seats 24 of the head body 8, for example by screwing. Through the spray seats 24, nozzles 20 receive the water to spray through one or more water feeding ducts 10 that run inside the spray head. The nozzles are provided with spray holes 28 preferably having the same configuration as the core making hole . [0027] The core maker 16 has a core making hole 30 suitable for spraying a mixture of air and water for generating said cores . Preferably, the mixture comprises a very small amount of water as compared to that of air. [0028] According to an embodiment , the spray head 4 for the production of artificial snow comprises a head body 8 having at least one spray wall 12 suitable for spraying a mixture of air and water for the production of artificial snow, at least one core maker 16 arranged on said spray wall 12 and suitable for spraying cores of artificial flakes . [0029] The spray head comprises at least one water feeding duct 10 that intercepts the at least one first nozzle 20 and comprises at least one air feeding duct 11 that delivers compressed air to said at least one core maker 16. [0030] Advantageously, the spray head comprises at least one shutter 40 that is subject to a pressure action by the water and by the air, said shutter 40 being arranged in fluid communication with at least a second nozzle 20' . [0031] Advantageously, shutter 40 is movable along an axial direction X from a closed position wherein it closes the fluid communication between the water feeding duct 10 and the second nozzle 20' to an open position wherein it puts the water feeding duct 10 in fluid connection with the second nozzle 20', so that the second nozzle 20' is fed by the water feeding duct 10.

[0032] The shutter is subject to the action of differential pressure between the water pressure of the water feeding duct 10 and the air pressure of the air feeding duct 11, the movement between the open position to the closed position and vice versa being controlled by said pressure difference .

[0033] Shutter 40 is arranged so as to intercept a first chamber 50 wherein the water feeding duct 10 leads and a second chamber 60 wherein the air feeding duct 11 leads. [0034] According to an embodiment, the shutter comprises a closing portion 64 suitable for sealing a connection channel 68 between said first chamber 50 and the at least one second nozzle 20', so as to allow or prevent the outlet of water through the second nozzles 20' . [0035] For example, the closing portion 64 comprises a tubular portion provided with a first seal 70 suitable for obtaining a seal with an inner side wall 74 of said connection channel 68.

[0036] According to an embodiment, shutter 40 comprises a first thrust surface 80, facing the first chamber 50 and subject to the water pressure action of the water feeding duct 10, so as to exert an axial thrust action on shutter

40 for opening said connection channel 68.

[0037] According to an embodiment, the first thrust surface 80 is defined by a first collar 84 directly facing the first chamber 50.

[0038] Preferably, said first collar 84 is coaxial relative to said axial direction X.

[0039] According to an embodiment, shutter 40 comprises a second seal 88 suitable for obtaining a seal for preventing a connection between the first and the second chamber 50, 60.

[0040] According to an embodiment, shutter 40 comprises a second thrust surface 92, facing the second chamber 60 and subject to the air pressure action of the air feeding duct 11, so as to exert an axial thrust action on the shutter for closing said connection channel 68.

[0041] Preferably, said second thrust surface 92 is defined by a second collar 96 directly facing the second chamber 60. [0042] Preferably, shutter 40 comprises a third seal 98 suitable for obtaining an air seal on the side of the second chamber 60. [0043] According to an embodiment, between the first and the second chamber 50, 60 the head body 8 comprises a stop 100 suitable for making a travel end to the movement of the shutter to the closed position.

[0044] Preferably, said stop 100 is substantially counter shaped relative to the second thrust surface 92 of shutter 40.

[0045] Preferably, on the side of the air feeding duct 11 shutter 40 comprises a stop 104 suitable for making a travel end to the opening movement of shutter 40. [0046] For example, stop 104 is obtained by a screw means, at least partly screwed in the shutter, so as to adjust the travel end .

[0047] According to a further embodiment , the spray head 4 comprises elastic preload means (not shown) , suitable for axially preloading shutter 40 in an open or closed configuration so as to suitably calibrate the valve opening or closing.

[0048] According to a possible embodiment, the spray head comprises at least two spray walls 12 angled relative to each other and each provided with at least one core maker 16 and with at least one nozzle 20. [0049] Preferably, the spray head comprises two spray walls perpendicular to one another and the water feeding ducts 10 as well as the compressed air feeding ones 11 concurrently feed the two spray walls through branches 110 arranged inside the head body.

[0050] According to further embodiments, the spray head comprises a plurality of shutters suitable for allowing the feeding of a plurality of stages so as to reduce the number of water feeding ducts in the spray head. [0051] The operation of a spray head according to the present invention will now be described.

[0052] In standard operating conditions of the spray head, the air of the air feeding duct blocks the shutter in closed condition since the pressures of air and water acting on the respective thrust surfaces, force the shutter to closed condition (figures 4B and 6) . [0053] As long as the predetermined water pressure value does not exceed a threshold value, the water feeding duct only feeds a predetermined first stage. On the other hand, when the atmospheric conditions allow increasing the production of snow, it is possible to increase the water pressure in such duct .

[0054] In this way, the increased water pressure allows the movement of the shutter from the closed position to the open one and as a consequence, also the second stage in fluid association with the first stage automatically opens. In this way both the first and the second stage are put in fluid connection with each other and fed at the same pressure (figures 4A and 5) . [0055] When the water delivery pressure is decreased, the system automatically returns the shutter to the closed position, since below the predetermined water pressure threshold value the force exerted by the air overcomes the thrust action of the water on the shutter. [0056] As it can be understood from the description, the spray head according to the present invention allows overcoming the disadvantages of the spray heads of the prior art . [0057] In fact, the spray head according to the invention allows limiting the number of water feeding ducts, avoiding the use of a duct for each stage. [0058] In fact, a same feeding duct may be used for feeding two different stages, thereby halving the number of ducts required. [0059] The opening or closing of the various stages may be easily modified by acting on the sections of the thrust surfaces or also inserting suitable elastic preload means. [0060] The system therefore in a totally automated manner performs a self-regulation by opening and closing the various stages based on the water feeding pressures. [0061] The spray head according to the invention is also inexpensive to make and less complex than the spray heads of the prior art .

[0062] A man skilled in the art may make several changes and adjustments to the spray heads described above in order to meet specific and incidental needs, all falling within the scope of protection defined in the following claims .

Claims

1. Spray head (4) for the production of artificial snow comprising a head body (8) having at least one spray wall (12) suitable for spraying a mixture of air and water for the production of artificial snow, at least one core maker (16) arranged on said spray wall

(12) and suitable for spraying cores of artificial flakes, at least a first nozzle (20) suitable for spraying a water jet suitable for intercepting said cores and favouring the growth thereof into snow flakes,

- the spray head (4) comprises at least one water feeding duct (10) that intercepts the at least one first nozzle and comprises at least one air feeding duct (11) that delivers compressed air to said at least one core maker characterised in that

- the spray head (4) comprises at least one shutter (40) that is subject to a pressure action by the water and by the air, said shutter (40) being arranged in fluid communication with at least a second nozzle (20'),

- the shutter (40) is movable along an axial direction (X) from a closed position wherein it closes the fluid communication between the water feeding duct (10) and the second nozzle (20') to an open position wherein it puts the water feeding duct (10) in fluid connection with the second nozzle (20'), so that the second nozzle (20') is fed by the water feeding duct (10) .

2. Spray head (4) according to claim 1, wherein the shutter (40) is subject to the action of differential pressure between the water pressure of the water feeding duct (10) and the air pressure of the air feeding duct

(11) , the movement between the open position to the closed position and vice versa being controlled by said pressure difference.

3. Spray head (4) according to claim 1 or 2, wherein said shutter (40) is arranged so as to intercept a first chamber (50) wherein the water feeding duct (10) leads and a second chamber (60) wherein the air feeding duct (11) leads.

4. Spray head (4) according to claim 3, wherein the shutter (40) comprises a closing portion (64) suitable for sealing a connection channel (68) between said first chamber (50) and the at least one second nozzle (20'), so as to allow or prevent the outlet of water through the second nozzles (20') .

5. Spray head (4) according to claim 4, wherein the closing portion (64) comprises a tubular portion provided with. a first seal (70) suitable for obtaining a seal with an inner side wall (74) of said connection channel (68) .

6. Spray head according to any one of the previous claims, wherein the shutter (40) comprises a first thrust surface (80) , facing the first chamber (50) and subject to the water pressure action of the water feeding duct

(10) , so as to exert an axial thrust action on the shutter (40) for opening said connection channel (68) .

7. Spray head according to claim 6 , wherein said first thrust surface (80) is defined by a first collar (84) directly facing the first chamber (50) .

8. Spray head according to claim 7 , wherein said first collar (84) is coaxial relative to said axial direction

(X) •

9. Spray head according to any one of claims 3 to 8 , wherein the shutter (40) comprises a second seal (88) suitable for obtaining a seal for preventing a connection between the first and the second chamber (50, 60) .

10. Spray head according to any one of the previous claims, wherein the shutter (40) comprises a second thrust surface (92) , facing the second chamber (60) and subject to the air pressure action of the air feeding duct (11) , so as to exert an axial thrust action on the shutter (40) for closing said connection channel (68) .

11. Spray head according to claim 10, wherein said second thrust surface (92) is defined by a second collar (96) directly facing the second chamber (60) .

12. Spray head according to any one of claims 3 to 11, wherein the shutter (40) comprises a third seal (98) suitable for obtaining an air seal on the side of the second chamber (60) .

13. Spray head (4) according to any one of claims 3 to 12, wherein between the first and the second chamber (50,

60) the head body (8) comprises a stop (100) suitable for making a travel end to the movement of the shutter (40) to the closed position.

14. Spray head (4) according to claim 13, wherein said stop (100) is substantially counter shaped relative to the second thrust surface (92) of the shutter (40) .

15. Spray head according to any one of the previous claims, wherein on the side of the air feeding duct (11) the shutter (40) comprises a stop (104) suitable for making a travel end to the opening movement of the shutter (40) .

16. Spray head according to claim 15, wherein the stop (104) is obtained by a screw means, at least partly screwed in the shutter (40) , so as to adjust the shutter travel end.

17. Spray head according to any one of the previous claims, comprising elastic preload means, suitable for axialIy preloading the shutter in an open or closed configuration so as to suitably calibrate the valve opening or closing.

18. Spray head according to any one of the previous claims, wherein the spray head (4) comprises at least two spray walls (12) angled relative to each other and each provided with at least one core maker (16) and with at least one nozzle (20) .

19. Spray head according to any one of the previous claims, wherein the spray head comprises two spray walls (12) perpendicular to one another and the water feeding ducts (10) as well as the compressed air feeding ones (11) concurrently feed the two spray walls through branches (110) arranged inside the head body.