Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
  • B05B7/02—Spray pistols; Apparatus for discharge
  • B05B7/04—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge
  • B05B7/0416—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge with arrangements for mixing one gas and one liquid
  • B05B7/0433—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge with arrangements for mixing one gas and one liquid with one inner conduit of gas surrounded by an external conduit of liquid upstream the mixing chamber
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B1/00—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means
  • B05B1/02—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means designed to produce a jet, spray, or other discharge of particular shape or nature, e.g. in single drops, or having an outlet of particular shape
  • B05B1/06—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means designed to produce a jet, spray, or other discharge of particular shape or nature, e.g. in single drops, or having an outlet of particular shape in annular, tubular or hollow conical form
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B1/00—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means
  • B05B1/26—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means with means for mechanically breaking-up or deflecting the jet after discharge, e.g. with fixed deflectors; Breaking-up the discharged liquid or other fluent material by impinging jets
  • B05B1/262—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means with means for mechanically breaking-up or deflecting the jet after discharge, e.g. with fixed deflectors; Breaking-up the discharged liquid or other fluent material by impinging jets with fixed deflectors
  • B05B1/265—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means with means for mechanically breaking-up or deflecting the jet after discharge, e.g. with fixed deflectors; Breaking-up the discharged liquid or other fluent material by impinging jets with fixed deflectors the liquid or other fluent material being symmetrically deflected about the axis of the nozzle
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
  • B05B7/02—Spray pistols; Apparatus for discharge
  • B05B7/10—Spray pistols; Apparatus for discharge producing a swirling discharge
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25C—PRODUCING, WORKING OR HANDLING ICE
  • F25C3/00—Processes or apparatus specially adapted for producing ice or snow for winter sports or similar recreational purposes, e.g. for sporting installations; Producing artificial snow
  • F25C3/04—Processes or apparatus specially adapted for producing ice or snow for winter sports or similar recreational purposes, e.g. for sporting installations; Producing artificial snow for sledging or ski trails; Producing artificial snow
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25C—PRODUCING, WORKING OR HANDLING ICE
  • F25C2303/00—Special arrangements or features for producing ice or snow for winter sports or similar recreational purposes, e.g. for sporting installations; Special arrangements or features for producing artificial snow
  • F25C2303/048—Snow making by using means for spraying water
  • F25C2303/0481—Snow making by using means for spraying water with the use of compressed air

Definitions

• the present invention relates to snow cannons for the production of artificial snow by spraying a mixture of air and water.
• the development of winter sports has given rise in recent years to the need to produce artificial snow to charge or recharge the ski slopes during periods of insufficient snowfall.
• the document DE 29 41 052 A teaches to mix air and water in a mixing and compression chamber limited by two conical inner and outer coaxial walls converging. By their converging conical shape, the walls of the mixing chamber gradually compress water and air during their mixing. Water is injected in several peripheral jets, according to a rotary movement. The air is injected from the conical inner wall of the mixing and compression chamber, in several jets in substantially longitudinal directions.
• the mixing chamber is connected directly to the outlet orifice, by its zone of smaller section, without additional narrowing.
• the devices of the first family ensuring a high spraying at the end of a pole, need an inlet air pressure of 8 to 10 X 10 5 Pa, and a water pressure of at least 16 to 20 X 10 5 Pa. Spraying at height often leads to dispersing the snow outside the runway surface to be recharged, in the event of wind, even a weak one.
• the support structure necessary to hold the pole leads to a unitary installation whose weight is generally greater than 100 kilograms.
• the second family fan gun devices can deliver 400 to 800 liters of water per minute for a unit installation weight of 400 to 1000 kilograms. These devices also require an inlet water pressure of between 16 and 20 X 10 5 Pa approximately, as well as an electrical connection of 20 to 50 kilowatts. It is therefore necessary to provide expensive power cables to bring the energy to the snow production site.
• EP 0 018 280, DE 29 41 052 A, FR 2 376 384 A, JP 06 074627 A or EP 0 084 186 A also need a high water pressure, greater than 10 X 10 5 Pa.
• the pressure of inlet air must be of the order of 8 X 10 5 Pa. Otherwise, the production of snow is defective and the cannon mainly spits droplets of liquid water.
• all these known devices require a large infrastructure, most often a pumping station with high pressures at the start to guarantee a pressure of 8 to 16 ⁇ 10 5 Pa at the top of the tracks.
• the pipes in which the fluids flow must hold pressures of more than 40 X 10 5 Pa on average, which makes them heavy and expensive to purchase and to set up.
• the guns themselves are also heavy and bulky, difficult to transport along rugged ski slopes.
• the devices for producing compressed air capable of reaching the pressures necessary for the guns currently used are relatively expensive, since the pressures are higher than those of the versatile compressors generally used on construction sites for feeding jackhammers.
• the present invention provides a snow cannon for the production of snow.
• artificial spraying of air and water mixture comprising a hollow body having a mixing chamber oriented along a longitudinal axis, bounded by a lateral peripheral wall and communicating with the outside by a front outlet passage, having means water inlet for injecting pressurized water into the mixing chamber in one or more preferential directional flows in the peripheral zone of the mixing chamber along the peripheral wall and in a rotary movement around the axis longitudinal of the mixing chamber, and having shaped air intake means for injecting compressed air into the mixing chamber from the central zone of the mixing chamber;
• the air intake means are shaped to inject air in the form of one or more air jets each directed to cut off one of said preferential directional flows of water;
• the mixing chamber comprises an upstream expansion section followed by a downstream compression section, the upstream expansion section communicating with the water intake means and with the air intake means and having a cross section greater than that of the water and air intake means to allow the expansion of the
• the two-fluid gun according to the invention can be compact and light, according to a weight of 2 to 3 kilograms, which is easily moved.
• a gun is capable of operating at variable flow rates as a function of the outlet passage section, and with water inlet pressures of the order of 4 ⁇ 10 5 Pa and an air pressure of order of that produced by the usual site compressors for supplying jackhammers. Under certain conditions, it is possible to snow with an inlet water pressure which can go down to around 3 X 10 5 Pa. The compressed air pressure is slightly higher than that of water.
• the lateral peripheral wall is substantially cylindrical.
• the outlet passage is an orifice of annular shape.
• the mixture of air and water exits through the orifice in tubular and rotating form, and it pushes the outside air forwards, inducing a central depression which favors the entry of outside air currents towards the center. This likely promotes the fragmentation of the droplets and causes better heat exchange with the outside air and the droplets.
• the mixture cools faster and freezes quickly before it hits the ground.
• the air expands rapidly and separates the parts of water which are close to it. This likely promotes the formation of snowflakes.
• the water intake means comprise a plurality of helical channels distributed at the periphery around the longitudinal axis, and the helical channels can be connected, upstream, to an annular water distribution chamber. communicating with a peripheral water inlet.
• the air intake means can comprise a plurality of air channels.
• the air channels can advantageously be divergent to direct the air obliquely towards the peripheral wall.
• the air channels can communicate with the mixing chamber by injection orifices distributed along a ring of a rear front wall. This favors substantially the formation of snowflakes at the outlet, probably due to the swirling expansion of the fluids during their mixing in the upstream section of the mixing chamber.
• an adjustment plate is provided pierced with an annular series of through holes, the adjustment plate coming to bear against the rear front wall and being able to be pivoted about the longitudinal axis between a position of complete opening in which each air channel outlet orifice faces a through hole in the adjustment plate, and partial shutter positions in which the adjustment plate is slightly pivoted about the longitudinal axis to offset at least partially the plate holes with respect to the outlet openings of the air channels.
• the central core is elongated longitudinally and is adjustable in longitudinal position along the longitudinal axis, and its cross section is variable longitudinally. It is thus possible to adjust to a certain extent the diameter of the mixing jet a few centimeters from the outlet, to adapt to the external conditions of humidity and temperature to optimize the quality of the snow, and to adjust the shooting distance.
• the central core can also comprise several external radial annular ribs, of different diameters, separated by a frustoconical section.
• the central core can advantageously be conical, allowing continuous adjustment of the section of the outlet passage.
• FIG. 1 is a side view in longitudinal section of a snow cannon structure according to an embodiment of the present invention
• FIG. 4 is a top view in partial horizontal section along the plane B-B of Figure 1.
• a snow cannon according to the invention comprises an elongated hollow body 1, for example generally cylindrical, having a mixing chamber
• the air intake means constituted by the air channels 11-16 are shaped to inject the compressed air from the central zone of the mixing chamber 2 according to one or more air jets directed obliquely towards the wall peripheral 3. In this way, the compressed air jets penetrate into the preferential directional flow (s) of rotary water in the upstream expansion section 201 of the mixing chamber 2.
• the helical water intake channels 6-10 connect to an annular water distribution chamber 17, externally limited by an external cylindrical wall 18 extending rearward the peripheral wall 3 of the mixing chamber 2, and internally limited by an inner cylindrical wall 19.
• the inner cylindrical wall 19 is connected to the outer cylindrical wall 18 upstream by a posterior crown 20, and downstream by an intermediate transverse wall 21 comprising the helical channels 6-10 and the divergent channels 11-16.
• the outer cylindrical walls 3 and 18 are cut along the plane BB of Figure 1, while the intermediate transverse wall 21 is not cut to reveal, according to its periphery, the helical channels such as the channels helical 6 and 8.
• the air channels 11-16 are connected to an axial air supply pipe 22, externally limited by the internal cylindrical wall 19.
• the axial air supply pipe 22 communicates with a central air inlet 23, while the annular water distribution chamber 17 communicates with a peripheral water inlet 24.
• the upstream expansion section 201 of the chamber of mixing 2 communicates with the water intake means and with the air intake means, and has an upper cross section to that of the water and air intake means, to allow the fluids to expand during their mixing.
• the mixing chamber 2 is limited upstream by a rear front wall 203, which is for example formed by the intermediate transverse wall 21 itself.
• the air channels 11-16 communicate with the mixing chamber 2 by injection orifices distributed in a coaxial ring on the rear front wall 203.
• the adjustment plate 25 can be pivoted about the longitudinal axis II between a fully open position in which each air channel outlet orifice 11-16 faces a through hole of substantially the same cross section of the adjustment plate 25, and partial shutter positions in which the adjustment plate 25 is slightly pivoted about the longitudinal axis II to at least partially offset the plate holes relative to the outlet orifices of the air channels 11-16.
• the adjustment plate 25 thus makes it possible both to create turbulence in the air entering the mixing chamber 2, and to regulate the air flow.
• the outlet passage 4 is an orifice of annular shape, around a central core 26.
• the central core 26, engaged in the outlet passage 4 comprises a first external radial annular rib 27, and a second external radial annular rib 28 of diameter greater than that of the first external radial annular rib 27 from which it is separated by a frustoconical section 29.
• the central core 26 is preferably adjustable in longitudinal position along the longitudinal axis II.
• the central core 26 is in the form of a reversible nut engaged by screwing and selectively locked in the axial position on an axial threaded rod 30 of the body 1.
• the axial rod 30 is screwed into a threaded axial bore 31 of the intermediate transverse wall 21.
• the longitudinal position of the central core 26 is adjusted relative to an internal radial annular lip 32 of the body 1 which externally limits the outlet passage 4.
• the outlet passage 4 is limited externally by the internal radial annular lip 32 of the body 1, and internally by the central core 26.
• the outlet passage 4 is substantially limited by the annular lip internal radial 32 and by the first external radial annular rib 27 of the central core 26.
• the internal radial annular lip 32 is an edge limited by two faces forming between them an angle of less than approximately 110 °. This promotes abrupt swirling of the outlet fluids, for the formation of snowflakes. This effect is further increased in the presence of an external radial annular rib 27 of the central core 26 facing the internal radial annular lip 32.
• the axial rod 30 also serves to hold the adjustment plate 25: the rod 30 passes through a central hole in the adjustment plate 25, and the adjustment plate 25 is held pressed against the intermediate transverse wall 21 by a nut clamp 33 screwed onto the axial rod 30.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Mechanical Engineering (AREA)
• Thermal Sciences (AREA)
• General Engineering & Computer Science (AREA)
• Nozzles (AREA)
• Materials Applied To Surfaces To Minimize Adherence Of Mist Or Water (AREA)
• Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=9530422

Family Applications (1)

Country Status (5)

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Family Cites Families (8)

• 1998
  • 1998-09-11 FR FR9811462A patent/FR2783310B1/fr not_active Expired - Fee Related
• 1999
  • 1999-08-31 EP EP99946082A patent/EP1114287B1/de not_active Expired - Lifetime
  • 1999-08-31 WO PCT/EP1999/006421 patent/WO2000016026A1/fr not_active Ceased
  • 1999-08-31 AT AT99946082T patent/ATE220193T1/de active
  • 1999-08-31 DE DE69902048T patent/DE69902048D1/de not_active Expired - Lifetime

Non-Patent Citations (1)

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