EP0636844A1 - Verfahren zur Erhaltung einer Schneedecke - Google Patents

Verfahren zur Erhaltung einer Schneedecke Download PDF

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Publication number
EP0636844A1
EP0636844A1 EP94115422A EP94115422A EP0636844A1 EP 0636844 A1 EP0636844 A1 EP 0636844A1 EP 94115422 A EP94115422 A EP 94115422A EP 94115422 A EP94115422 A EP 94115422A EP 0636844 A1 EP0636844 A1 EP 0636844A1
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EP
European Patent Office
Prior art keywords
snow
snow surface
air
ice
dehumidifying
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP94115422A
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English (en)
French (fr)
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EP0636844B1 (de
Inventor
Koji Morioka
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Taikisha Ltd
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Taikisha Ltd
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Filing date
Publication date
Application filed by Taikisha Ltd filed Critical Taikisha Ltd
Priority to DE69132883T priority Critical patent/DE69132883D1/de
Publication of EP0636844A1 publication Critical patent/EP0636844A1/de
Application granted granted Critical
Publication of EP0636844B1 publication Critical patent/EP0636844B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • F25C2303/042—Snow making by using solid ice, e.g. ice crushing

Definitions

  • the present invention relates to a method of forming an artificial snow surface and an ice crusher machine used in the method.
  • the invention also relates to a method of maintaining a snow surface.
  • conventional method e.g. the Japanese laid-open utility model gazette No. 63-113866 and U.S.P. 2,676471, to be hereinafter referred to as conventional method 1
  • water and compressed gas mainly, air
  • conventional method 1 water and compressed gas (mainly, air) both sufficiently refrigerated are sprayed through a nozzle, such that the sprayed mixture is frozen by adiabatic expansion at an atmosphere under the freezing point temperature to be formed into fine ice particles and then the ice particles are accumulated to form a snow surface.
  • ice cubes are prepared and these cubes are crushed by means of an ice crusher machine to be rendered into fine ice particles. Then, these particles are sprayed around to be accumulated for forming a snow surface.
  • a weter-receiving bank as an ice-making bank is constructed along a skiing slope. Under a below-freezing point temperature, water is frozen on the ice-making bank to form an ice surface thereon. Then, this ice surface is crushed off by a crusher into fine ice particles and concurrently therewith the ice particles are scattered about onto the skiing slope beside the ice-making bank to form an artificial snow surface.
  • an ice layer is formed on a skiing slope by sprinking water under a below-freezing point temperature. Then, the formed ice layer is crushed by means of a roller equipped with a sieving machine driven on the layer to form the layer into fine ice particles.
  • the Japanese PCT-laid-open patent application No. 62-503118 discloses a still further method (to be hereinafter referred to as the conventional method 5).
  • this method mixture of water and surface-activating agent is stirred to foam. And, this foam is laid out on a skiiing slope to be frozen at a below-freezing point temperature. Thereafter, a roller is driven on the frozen foam in order to crush it into ice particles forming a snow surface.
  • the above-identified PCT application discloses a further method (to be hereinafter referred to as the conventional method 6).
  • the above-described foam generated by stirring the mixture of the water and surface-activating agent is laid out on a flexible grating preliminarily refrigerated by a freezer unit, so that the foam is frozen in the grating. Thereafter, a roller is passed on the frozen foam to crush it into ice particles forming a snow surface.
  • the conventional method 1 has the significant shortcoming of requiring a great amount of energy for realizing and maintaining the below-freezing point atmosphere regardless of the current climate condition.
  • the conventional method 2 has the problem of requiring a great amount of labor and costs for the transport of the ice cubes separately prepared.
  • the conventional method 3 has the problem of requiring a significant amount of space for constructing the water-receiving surface along the skiing slope.
  • the conventional method 4 suffers the problem that the roller often fails to pulvarize the ice layer into sufficiently small particles. Further, if a fine sieve is used to select fine, i.e. good ice particles alone, there will occur a great amount of waste of the unused particles. Conversely, if a rough sieve is used for the sake of economy, there will occur significant quality deterioration, i.e. roughness in the obtained ice particles.
  • the snow surface is formed by pulverizing the frozen foam by means of the roller. Accordingly, the resultant snow surface tends to be too compacted and hard which provides a skier with an uncomfortable and unnatural skiing feel, as compared with a snow surface formed by natural snow.
  • the conventional method 5 further suffers the same problem of the method 1, i.e. the problem of requring an enormous amount of energy for artificially creating the below-freezing point atmosphere regardless of the natural climate.
  • the primary object of the present invention is to provide the method of forming an artificial snow surface with such improvement as to achieve energy, cost and space economies and a snow surface of good quality.
  • the second object of the present invention is to provide a method for effectively maintaining the snow surface formed by the above-described method of the invention.
  • the third object of the present invention is to provide an ice crusher machine useful in the implementation of the invention's method of forming an artificial snow surface.
  • a method of forming an artificial snow surface comprises the steps of: spraying water onto a floor incorporating a refrigerating means; freezing the water by said refrigerating means to form an ice layer on the floor; shaving a surface of said ice layer to generate artificial snow consisting of fine ice particles; and forming an artificial snow layer having an artificial snow surface by leaving the shaved snow on the remain of the ice layer in the course of said shaving step.
  • the sprayed water is directly refrigerated to freeze by means of the refrigerating means incorporated in the floor. Accordingly, the method can save energy required for freezing the sprayed water, as compared with the conventional methods 1, 3, 4 and 5 which freeze the sprayed water or foam by way of the atmosphere whose temperature forcibly controlled below the freezing point by refrigerating a great amount of ambience air.
  • the ice layer as the snow source is directly formed by refrigerating the water sprayed on the floor where the ice layer is to be formed. This is advantageous for significantly saving the labor and costs required for transporting the ice cubes as the snow source from its factory to the final destination which is the case with the conventional method 2.
  • the method of the present invention can eliminate the space required solely for installing the ice-making bank, since the snow surface per se is utilized as the ice-making surface.
  • the method of the present invention consequently achieves significant installment space ecomony.
  • the artificial snow is generated by shaving the surface of the ice layer and the shaved ice is left on the remain of the ice layer, such that the invention's method can provide snow with finer and better quality, when compared with the conventional method 4 where the roller is used for crushing the ice layer. Further, there occurs no waste in the use of the snow-source ice, and the method can provide good-quality snow in a constant and stable manner. Moreover, when compared with the conventional methods 5 and 6 where the snow is formed by crushing frozen foam by means of a roller, the artificial snow obtained by the present invention will have fine and good quality almost as good and fine as natural snow.
  • the invention has achieved its intended object of providing the method of forming an artificial snow surface with such improvement as to achieve energy, cost and space economies and a snow surface of good quality.
  • a method of maintaining the artificial snow surface obtained in the above-described manner, according to the present invention is characterized by the step of: dehumidifying ambient air present adjacent above the snow surface in order to present water content in the ambient air from frosting.
  • the method prevents frosting of the air on the snow surface (i.e. transfer of the heat from the air to the snow, such that the method can prevent also disadvantageous increase in the load in the refrigeration of the snow surface.
  • the refrigerating machine inevitably suffers low operation efficiency in refrigerating the snow surface because the machine has to provide a very low temperature for this purpose. Therefore, such effective prevention of increase in the load can achieve significant reduction in the running cost of the system.
  • an adsorption type dehumidifying device is used as the dehumidifying means.
  • the adsorption type humidifying device When the adsorption type humidifying device is used, there occurs increase in the temperature of the processed air in association with its dehumidifying operation. This temperature increase can be effectively utilized for preventing excessive refrigeration of the snow surface due to absorption of heat from the ambience air, which tends to occur during the winter season. Such excessive refrigeration of the snow surface will result in deterioration in the quality of the snow. Then, the prevention of excessive refrigeration can provide the skier with comfortable and smooth skiing feel.
  • a cooling type dehumidifying device can be also used as the dehumidifying means.
  • the device When this cooling type dehumidifying device is used, there occurs decrease of the temperature in the processed air. Accordingly, the device can effectively restrict transfer of the heat from the ambience air to the snow surface, which heat transfer often occurs during the summer season. Thus, in this case too, the snow surface can be maintained at good skiing condition through the prevention of frosting of water content present in the ambience air on the snow surface, and further much energy can be saved through prevention of melting of the snow.
  • the use of the adsorption type dehumidifying device provides the advantage of restricting excessive refrigeration of the snow surface during the winter season while the use of the cooling type dehumidifying device provides the advantage of restricting the heat transfer from the ambience air to the snow surface during a warm season.
  • the two types of dehumidifying devices can achieve both the comfortable skiing feel and the running cost reduction.
  • An ice crushing machine usuable for forming an artificial snow surface comprises: a propelling means for propelling a machine body on an ice layer or an artificial snow surface; and a shaving blade attached to the machine body for shaving a surface of said ice layer.
  • the shaving blade mounted on the machine body shaves the surface of the ice layer to render it into fine ice particles forming artificial snow.
  • the propelling machine leaves behind the shaved snow particles on the remain, i.e. unshaved portion, of the ice layer, the machine can form an artificial snow surface of a desired area on the ice layer.
  • the shaving blade has its shaving edge oriented along the thickness of the ice layer.
  • This preferred arrangement renders the propelling direction of the machine body normal to the shaving direction of the shaving blade, thus enabling the propelling operation and the shaving operation of the machine to be functionally independent of each other. That is, these operations can take place without one being adversely affected by the other.
  • the shaving blade to effect the shaving in a direction slanted relative to the thickness direction of the ice layer.
  • the slanted blade edge arrangement has the advantage that the cutting depth gradually increases adjacent a lower end thereof so that a larger amount of artificial snow can be generated.
  • the shaving blade can have its shaving edge oriented substantially normal to the direction of the thickness of the ice layer.
  • FIG. 1 through 5 illustrate one preferred embodiment of the present invention
  • Fig. 1 shows a construction of an indoor skiing slope.
  • Reference numeral 1 denotes a housing.
  • Numeral 2 denotes a sloped floor incorporating a heat insulating means.
  • Numeral 3 denotes a refrigerating-medium pipe embedded substantially over the entire surface of the sloped floor 2.
  • Numeral 4 denotes a refrigerating machine for refrigerating a refrigerating medium (brine) to e.g. - 14 to - 22 degrees in Celsius.
  • Numeral 5 denotes an air-conditioner.
  • Numeral 6 denotes a cooling coil (for circulating cooling water at + 5 to + 7 degrees in Celsius.
  • Numeral 7 denotes a dehumidifying unit incorporated in the air-conditioner 5.
  • Numeral 8 denotes an air passage for combining an indoor air AT introduced through an air intake opening 9 with an outdoor air introduced an outdoor-air flow passage 10 and introducing this combined air into the air-conditioner 5 and then feeding the conditioned air into the ineterior of the housing through an air outlet opening 11.
  • Numeral 12 denotes an air exhaust passage for exhausting the indoor air AT by an amount corresponding to the amount of the introduced outdoor air.
  • a snow surface 13a For forming a snow surface 13a, an appropriate amount of water is sprayed over an entire surface of the sloped floor 2. Then, the sprayed water is frozen by the refrigerating-medium pipe 3. These operations are repeated to form a multiplicity of thin ice layers on the sloped floor 2 until an ice layer 14 having a predetermined thickness (a) is obtained.
  • the amount of the water sprayed at one time should be so controlled that the water will immediately freeze on the sloped floor 2 without falling off the floor.
  • the predetermined thickness (a) of the ice layer 14 preferably ranges between 100 and 150 mm.
  • a self-propelling type ice crusher machine 15 is driven on the entire surface of the ice layer 14. As the machine 15 being propelled, the machine 15 shaves a surface of the ice layer 14 to generate artificial snow consisting of fine ice particles. At the same time, as the propelling machine 15 leaves behind the generated artificial snow on the remain of the ice layer 14, an artificial snow layer 13 is formed on the ice layer 14, such that these layers 13 and 14 together form the snow surface 13a.
  • the dimension of the particle of the artificial snow can be varied through adjustment of a shaving depth of a rotary shaving blade 18a relative to the ice layer 14, in order to obtain such snow particle as most suitable for skiing.
  • the ice crusher machine 15 is driven on the ice layer 14 or on the formed snow layer 13 while shaving the surface thereof for a plurality of times. With these repeated operations, the snow layer 13 gradually increases in its thickenss (here, the afore-mentioned snow surface denotes such layer having its air content increased due to the transformation of the ice into the fine particles in comparison with the ice layer 14).
  • the thickness (b) of the snow layer 13 preferably ranges between 20 and 50 mm.
  • such additive is to be used, such material should be selected as is inexpensive and as will cause only minimal reduction in the heat transmitting ratio in the ice layer 14. Alternately, such reduction in the heat transmission ratio can be restricted by employing an additive consisting of very small particles to reduce the amount of the air present in the ice layer 14.
  • the formation of the ice layer 14 and the prevention of melting of the ice layer 14 and the snow layer 13 are effected by means of refrigeration via the refrigerating-medium pipe 3 as described above.
  • a cooling coil 6 is operated to cool the indoor air to provide skiers with comfortable atmosphere as well as to help the refrigerating-medium pipe 3 to prevent melting of the snow surface 13a.
  • the dehumidifying unit 7 In conditioning the indoor air AT, in addition to the cooling of the air AT by means of the cooling coil 6 when the ambient temperature is high, because the indoor air AT becomes moist by the breaths of the skiers and by the introduction of new outdoor air, the dehumidifying unit 7 is operated to dehumidify the moisted indoor air AT so as to maintain the dew point of the indoor air AT below the temperature of the snow surface 13a ranging between - 2 and - 3 degrees in Celsius thereby to maintain good skiing condition of the snow surface 13a.
  • the machine 15 includes a machine body 15a mounting a pair of right and left sledges 16 and a pair of right and left propelling wheels 17 as a propelling means for propelling the machine body 15a on the ice layer 14 or the snow surface 13a.
  • This propelling means need not be mounted to the machine body 15a. Instead, it is conceivable to propel the machine body 15a by means of a separate propelling means.
  • rotary shaving blades 18A as a blade means for shaving the surface of the snow surface 14.
  • the propelling wheels 17 serve to propel the machine body 15a straightway when these wheels 17 are rotated at a same speed in a same direction. Also, when these wheels 17 are rotated at different speeds or directions, these wheels 17 serve to steer the machine body 15a.
  • the plurality of shaving blades 18A are arranged in a radial pattern on a lower face of a rotary disc rotatable about a vertical axis P extending substantially normal to the ice layer 14. As these blades 18A are driven to rotate via the rotary disc 19 by a motor 20, the rotating blades 18A shave or cut the surface of the ice layer 14 by a certain depth and the cut ice as artificial snow is sent radially outwards to be left on the remain of the ice layer 14.
  • a blade edge 18a formed at a lower edge of each shaving blade 18A is inclined with an outer portion thereof relative to the radius of the rotary disc 19 being formed higher than an inner portion, such that the blade edge 18a when used shaves the ice layer 14 with an inclination relative to the direction of the thickenss of this ice layer 14.
  • the inclined blade edges 18a cut deeper at the lower sides thereof.
  • the blade edges 18a can cut deep with one shaving action thereby to efficiently generate a large amount of artificial snow.
  • the angle (A) of the inclination i.e. the inclination angle provided for smooth sending of the generated artificial snow outwards relative to the radius of the rotary disc 19
  • the angle (B) of the shaving blade 18A preferably ranges between 20 and 40 degrees.
  • the clearance angle (C) of the shaving blade 18A preferably ranges between 5 and 10 degrees.
  • the shaving blades 18A are replaceable when necessary. Also, at a center of the radial pattern arrangement of the shaving blades 18A, there is attached a cylinder member 21 for preventing intrusion and resultant clogging of the generated artificial snow.
  • the rotation speed of the rotary disc 19 is adjustable by an inverter control on the motor 20. Through this adjustment of the rotation speed, the quality of the artificial snow is adjusted.
  • the above-described ice crusher machine 15 is operated by a wireless remote control operation effected from an indoor monitor room R.
  • the shaving blades 18A are driven at a predetermined speed to shave the surface of the ice layer 14 while the machine 15 is propelled at a predetermined propelling speed over the entire surface of the ice layer 14 or the snow surface 13a, thereby to form a large area of the snow layer 13 having a predetermined thickenss (b) which consequently forms the snow surface 13a (i.e. skiing slope).

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Road Paving Structures (AREA)
EP94115422A 1991-11-12 1991-11-12 Verfahren und Vorrichtung zur Erhaltung einer Schneedecke Expired - Lifetime EP0636844B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE69132883T DE69132883D1 (de) 1991-11-12 1991-11-12 Verfahren und Vorrichtung zur Erhaltung einer Schneedecke

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP91310436A EP0541867A1 (de) 1991-11-12 1991-11-12 Verfahren zur Herstellung einer künstlichen Schneedecke, Eisbrecher dafür und Verfahren zur Erhaltung dieser Schneedecke

Related Parent Applications (2)

Application Number Title Priority Date Filing Date
EP91310436.0 Division 1991-11-12
EP91310436A Division EP0541867A1 (de) 1991-11-12 1991-11-12 Verfahren zur Herstellung einer künstlichen Schneedecke, Eisbrecher dafür und Verfahren zur Erhaltung dieser Schneedecke

Publications (2)

Publication Number Publication Date
EP0636844A1 true EP0636844A1 (de) 1995-02-01
EP0636844B1 EP0636844B1 (de) 2001-12-19

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EP94115422A Expired - Lifetime EP0636844B1 (de) 1991-11-12 1991-11-12 Verfahren und Vorrichtung zur Erhaltung einer Schneedecke
EP91310436A Withdrawn EP0541867A1 (de) 1991-11-12 1991-11-12 Verfahren zur Herstellung einer künstlichen Schneedecke, Eisbrecher dafür und Verfahren zur Erhaltung dieser Schneedecke

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP91310436A Withdrawn EP0541867A1 (de) 1991-11-12 1991-11-12 Verfahren zur Herstellung einer künstlichen Schneedecke, Eisbrecher dafür und Verfahren zur Erhaltung dieser Schneedecke

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Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2700835B1 (fr) * 1993-01-26 1995-04-21 Technip Cie Procédé et installation de production de neige.
NO337419B1 (no) * 2014-03-04 2016-04-11 Roy Erik Eriksson Kjøleanordning for kjøling av fast materiale og/eller frysing av væske
CN104964500B (zh) * 2015-07-05 2017-06-06 金烜伊 一种磨辊式碎冰造雪机
CN108992810B (zh) * 2018-08-31 2023-06-13 泉州魔力神工具制造有限公司 一种移动式清新空气调节器

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB421431A (en) * 1933-03-29 1934-12-20 James Govan Improvements relating to ice rinks
US2058919A (en) * 1933-01-17 1936-10-27 B F Sturtevant Co Air conditioning apparatus
US2203560A (en) * 1938-04-06 1940-06-04 Carrier Corp Air conditioning method
US2239190A (en) * 1933-12-01 1941-04-22 Gen Motors Corp Air conditioning method and apparatus
US3983713A (en) * 1975-05-05 1976-10-05 Maccracken Calvin D Method of creating and outdoor ice slab in summer weather and of reducing energy requirements for indoor and outdoor ice rinks
US3990260A (en) * 1975-04-04 1976-11-09 Eustis William E C Low-temperature dehumidifier
WO1989012793A1 (en) * 1988-06-22 1989-12-28 Clulow Malcom George Snow making equipment
WO1990010183A1 (en) * 1989-03-01 1990-09-07 Andrew Boyd French Snowmaking method and device
EP0508752A1 (de) * 1991-04-11 1992-10-14 Taikisha, Ltd. Verfahren zur Erzeugung einer Kunstschneedecke

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4345439A (en) * 1980-02-20 1982-08-24 Vencraft Corp. Snowmaking method and apparatus
EP0222843A1 (de) * 1985-06-04 1987-05-27 Permasnow (Australasia) Limited Herstellungsverfahren für kunstschnee
FR2607909B1 (fr) * 1986-12-05 1992-01-17 York Froid Ind Procede d'enneigement de pistes artificielles de ski alpin ou nordique et moyens de mise en oeuvre du procede

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2058919A (en) * 1933-01-17 1936-10-27 B F Sturtevant Co Air conditioning apparatus
GB421431A (en) * 1933-03-29 1934-12-20 James Govan Improvements relating to ice rinks
US2239190A (en) * 1933-12-01 1941-04-22 Gen Motors Corp Air conditioning method and apparatus
US2203560A (en) * 1938-04-06 1940-06-04 Carrier Corp Air conditioning method
US3990260A (en) * 1975-04-04 1976-11-09 Eustis William E C Low-temperature dehumidifier
US3983713A (en) * 1975-05-05 1976-10-05 Maccracken Calvin D Method of creating and outdoor ice slab in summer weather and of reducing energy requirements for indoor and outdoor ice rinks
WO1989012793A1 (en) * 1988-06-22 1989-12-28 Clulow Malcom George Snow making equipment
WO1990010183A1 (en) * 1989-03-01 1990-09-07 Andrew Boyd French Snowmaking method and device
EP0508752A1 (de) * 1991-04-11 1992-10-14 Taikisha, Ltd. Verfahren zur Erzeugung einer Kunstschneedecke

Also Published As

Publication number Publication date
EP0541867A1 (de) 1993-05-19
EP0636844B1 (de) 2001-12-19

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