EP0201987A1 - Dispositif et méthode pour préserver une base de neige sur une piste de ski - Google Patents

Dispositif et méthode pour préserver une base de neige sur une piste de ski Download PDF

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Publication number
EP0201987A1
EP0201987A1 EP86301655A EP86301655A EP0201987A1 EP 0201987 A1 EP0201987 A1 EP 0201987A1 EP 86301655 A EP86301655 A EP 86301655A EP 86301655 A EP86301655 A EP 86301655A EP 0201987 A1 EP0201987 A1 EP 0201987A1
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EP
European Patent Office
Prior art keywords
snow
slope
autumn
sheets
insulating
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.)
Withdrawn
Application number
EP86301655A
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German (de)
English (en)
Inventor
Adrian Brochu
André Brochu
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Individual
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Individual
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Publication date
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Publication of EP0201987A1 publication Critical patent/EP0201987A1/fr
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    • A—HUMAN NECESSITIES
    • A63—SPORTS; GAMES; AMUSEMENTS
    • A63C—SKATES; SKIS; ROLLER SKATES; DESIGN OR LAYOUT OF COURTS, RINKS OR THE LIKE
    • A63C19/00—Design or layout of playing courts, rinks, bowling greens or areas for water-skiing; Covers therefor
    • A63C19/12—Removable protective covers for courts, rinks, or game pitches or the like

Definitions

  • Skiing both downhill or on trails, is a world wide sport. Typically at the end of the skiing season in the spring, the snow gradually melts leaving the ground bare and subject to increasing temperature over the summer. In the .autumn the decreasing ambient temperature gradually cools the ground but it is rarely cold enough to hold the early fall snows. Thus before a base of snow can be built up for proper skiing conditions, several snow falls may be needed over a period of time.
  • Man-made snow customarily is not applied to a slope or trail until after a natural base has developed and the temperature is consistently well below freezing.
  • any melting of the snow thereunder during the spring, summer and autumn will be so limited that come late autumn and the first snows of winter there will be present an existing snow base capable of holding the early snows as they arrive and thus putting the slopes and trails in condition for use well in advance of the time that would occur had the underlying base not been preserved.
  • the invention contemplates the use of any presently known insulating materials and any others that may appear in the future so long as they in combination with the supporting flexible sheet structure are capable of insulating the snow from the summer heat to preserve it as a base on which the autumn and winter snows may build.
  • a mechanism may be provided at the sides of the slopes and trails for quickly and easily applying the insulating sheets to positions on the snow in the spring and removing them in the autumn.
  • the insulating sheets may of course be applied and removed by hand.
  • the sheets may be of any desired dimensions.
  • the sheets whether transverse or longitudinal will be rectangular and capable of being rolled up to remain out of the way at the side or bottom of the slope over the winter.
  • the means for winding the sheets in rolls may be mounted on or pulled by a truck or tractor which may be moved up the slope from one sheet to the next as they are moved in the autumn.
  • the sheets if stored in rolled up form can be manually unrolled across the slope in the spring and adjusted next to each other to completely cover the snow.
  • the insulating sheet may be in continuous form running from the top to bottom of the ski slope.
  • Cog railways may be installed on one or both sides of the slope with machines thereon connected by overhead means capable of rolling up the complete sheet to remove it from the snow in the autumn and to apply it in the spring.
  • the insulating sheets may be temporarily removed to provide skiing in summer on particular occasions such as the Fourth of July or a company outing for example. It has been determined that the melting that would occur during any such limited uncovered period in the summer would not materially diminish the snow volume that is to be preserved until autumn. The temporary removal and replacement of the covering can be expeditiously done by the machines provided for that purpose.
  • the insulating sheet will usually be laid directly on the snow as such arrangement has been found adequate to preserve the snow over the summer. If greater insulating effect is needed or wanted, it may be provided by spacing the insulating sheet a few inches above the snow through the use of spacers in the form of strips of foam rubber material. These strips of suitable dimensions to provide the desired spacing may be laid by hand close enough together to keep the sheet clear of the snow.
  • crossing areas On some slopes and/or trails it may be desirable or necessary to provide crossings for persons or animals. In such situations it is obvious that the crossing areas must remain uncovered during the summer and therefore will lack snow cover when the insulating sheets are removed from the covered areas in the autumn.
  • the deficiency can be overcome by locating the crossing areas adjacent places on the slope where the snow is deep enough to provide a preserved volume of snow adequate to be spread in part over the crossing areas in the autumn thereby to provide the slope with a continuous covering of snow the same as if there had been no summer crossing areas.
  • snow is concentrated by hand or machine into a series of piles over the entire length of the slope.
  • These piles will be high in the Centre and tapering downwardly to the surrounding ground.
  • the piles preferably will be circular.
  • the spacing of the piles will be determined by the depth and location of the snow available.
  • the piles of snow are then covered with sheets of insulating material of such character that a major volume of the piled snow will be preserved over the summer and early autumnmonths.
  • the piles When the average ambient temperature had dropped in theautumn to a degree at which the snow will not melt away, the piles will be uncovered and the snow redistributed, by hand and/or machine over the selected areas of the slope.
  • the depth of the redistributed snow now covering the selected slope area will be adequate for immediate skiing and will last until the arrival of natural snow. Should the arrival of natural snow be delayed, the snow base can be augmented by the application of man-made snow at the necessary locations after nightime freezing conditions have arrived in the autumn.
  • snow as used herein is to be understood as including any other form of frozen water as may be present on the covered slope such as ice, sleet and slush.
  • the object is to cover the snow on or in selected piles along the selected slopes or trails with insulating sheets without placing any limitations on the size or shape of the sheets, the nature of the insulation forming or carried by the sheets or the method or means for positioning and removing the sheets.
  • the sheets might be in rigid sections incapable of being rolled up but stackable when not in use. ;
  • Fig. 1 there is shown at 2 a vertical cross section of terrain which represents any ski slope or ski trail.
  • slope hereafter when the term slope is used it will include a ski trail which is ordinarily flatter and narrower than a ski slope.
  • the invention of preservation of snow is applicable to both the slope and trail.
  • a layer of snow 6 On the surface 4 of the slope is a layer of snow 6. This layer is the residual snow remaining at the time this particular slope is closed to skiing in the spring. Since practically all ski facilities have a plurality of slopes, closing one slope where it is desired to preserve snow over the summer, does not affect continued spring sking on the other slopes which are not to be covered. Therefore the slope that is to be closed will be closed when it still has an adequate depth of snow to last over the summer if properly protected against melting by correct insulation.
  • this residual snow on the closed slope is preserved over the summer by the application thereover of insulating covering sheets as indicated at 8.
  • This insulating material must have the capability of keeping the sun's radiant heat and the heat of the ambient air away from the residual snow to such extent that, in spite of what melting may occur over the several warm months of summer, there will always remain in the autumn enough snow to provide the starting base for the winter's natural or man-made snows.
  • the insulating cover may be in the form of a plurality of sheets 10 which may be laid mechanically or by hand over the snow in the spring and similarly removed in theautumn.
  • One of the plurality of sheets 10 is shown in Fig. 3.
  • This sheet, preferably covered top and bottom with aluminum foil is also shown in part in enlarged section in Fig. 2.
  • the sheet may be quilted by stitching as at 12 or otherwise constructed to hold against shifting insulating material 14 such as saw dust, fiberglass, rock wool, small sheets of insulating board or any other material effective against heat conduction that is presently available or may become available in the future.
  • the exterior coverings of aluminum foil may be applied to canvas or other fabrics, sheets or bubbles of plastics or other substances that may have suitable characteristics as to heat insulation, strength and waterproofness.
  • some experimentation may be necessary to relate the particular insulating covering to the depth of the radial snow and the average summer temperature of the geographical location of the slope.
  • a base 16 carries a sheet winding means comprised of bearings 18 and 20 through which extends a shaft 22 having on one end a bevel gear 24 driven by a cooperating bevel gear 26 carried by shaft 28 supported by bearing 30.
  • Shaft 30 and its gear 26 may be turned by a'hand crank 32 or a motor (not shown).
  • the base 16 carrying the winding means may be placed on the ground at the end of the sheet 10 by unloading it from a truck or it may be skidded along the ground to proper position or it may remain in permanent position on the truck or tractor or other conveyance.
  • the end of sheet 10 is secured to shaft 22, the shaft is rotated by the gearing and the sheet is wound up on the shaft as illustrated in Figs. 4 and 5.
  • the wound up sheet may be withdrawn from shaft 22 to be left over the winter on the adjacent ground.
  • the sheet 10 is to be replaced on the residual snow in the spring it is simply unrolled by hand across the slope to reassume the position shown in Figs. 1 and 3.
  • FIG. 6 A modification of the invention is shown in Figs. 6, 7, 8 and 9.
  • Fig. 6 the sloping terrain 40 has been covered in the summer with sheets of insulating material 42.
  • the following winter snow 44 has accumulated thereon. This slope being one on which the snow is to be preserved over the following summer is then covered in the spring with sheets of insulating material 46.
  • the combined insulating effects of the under and over sheets 42 and 46 on the snow 44 preserve the snow to such extent that there will remain an adequate snow base when the top sheets 46 are removed in the autumn.
  • the bottom sheets are allowed to remain continuously in place over subsequent seasons.
  • bottom sheets 42 has been found desirable in locations where the terrain is warmed by heat working in laterally from the sides of the slope or by subterranean conditions beyond control.
  • a convenient way of bringing the arrangement of Fig. 6 into being is to obtain a roll 48 of insulating material 50 having a total length at least twice the width of the slope to be covered.
  • half of the material may be unrolled as in Fig. 7 to cover the bare ground 52 across the slope.
  • the snow 54 will cover material 50 as illustrated in Fig. 8. Then in the spring when this slope is to be closed and the snow thereon preserved, the other half of roll 48 will be unrolled on top of the snow as at 56 in Fig. 9.
  • insulating sheets While it has been pointed out above that no limitations are to be placed on the construction of the insulating sheets, it is believed desirable to make reference to one specific sheet that provides adequate insulating properties for preserving the snow layer over the summer.
  • Such sheet is shown in Figs. 10 and 11. It comprises two layers of aluminum foil 58 and 60 spaced about 1/4 inch between which are two layers of polyethylene bubbles 62 and 64. These flattened bubbles about 3/8 inch in diameter are preferably arranged in triangular pattern, (see Fig. 11) and are bonded to themselves and to sheets 58 and 60 to form a strong sheet having the capability of substantially limiting passage of the sun's radiant heat and the heat of the ambient air to the snow thereunder.
  • the sheet may be further strengthened by a coating of clear polyethylene to both exterior sides. This sheet while light and very flexible is durable enough to be used repeatedly over the years to justify its initial cost.
  • FIG. 12 An alternative arrangement for preserving snow over the summer is shown in Figs. 12 and 13.
  • the snow at spaced areas 70 and 72 has been covered by the insulating sheets 74 and 76.
  • the uncovered part of the slope 78 becomes bare as the snow thereon melts to provide a crossing for persons and animals.
  • the crossing may then be covered by distributing thereon part of the preserved snow 70 and 72 from the adjacent covered areas.
  • some of the snow 70 and 72 has been shoveled or bulldozed onto the bare area 78 to create a continuous snow covered slope forming the desired autumn base.
  • FIG. 14 is a plan view of a slope 80 on which an adequate width of snow thereon has been covered by a continuous layer of insulating material 82. Because of the size of sheet 82 which for example might be 40 feet wide and a mile or more in length special means has been provided for laying and removing the cover. See Figs. 14 and 16. Tracks 84 and 86 have been laid on both sides of the slope. The conventional cog means (not shown) the electrically or gasoline propelled machines 88 and 90 may run together up and down the steep grade. A common shaft 92 extends across the slope between machines 88 and 90.
  • the machines include means for rotating shaft 92 so that the cover may be rolled up on or unrolled from the shaft (see Fig. 16) as the machines move down or up at appropriate speed along the tracks.
  • Suitable mechanisms such as splines or universal joints (not shown) in the shaft may be provided to compensate for non-uniform movement of the machines.
  • Fig. 15 shows how the effectiveness of the insulating sheet may be improved.
  • Strips of light foam rubber 94 of suitable cross sectional dimensions such as for example 2" x 3" or 4" x 4" are placed on the snow 96 prior to laying the insulating cover 98.
  • the spacing of the strips 94 will be close enough. to prevent appreciable sagging engagement of the cover with the snow.
  • the air barrier between the cover and the snow increases the insulating effect of the cover.
  • Fig. 17 is intended to represent any ski slope 102 which is covered with snow 104.
  • the snow covered area of the slope is shown as having top, side and bottom boundaries indicated at 106, 108, 110 and 112.
  • Fig. 18 is a vertical section taken on the line 18-18 of Fig. 17 showing the ground 114 with the snow 104 covering the sloping surface 102.
  • the upper limit of the snow with which we are concerned is at 106 and the bottom limit at 108.
  • Fig. 18 is a section taken on the line 19-19 of Fig. 18.
  • Figs. 17-19 is intended to include any ski slope having thereon snow (natural, natural and man-made or man-made) toward the end of the skiing season when the operator elects to close the slope.
  • the depth and disposition of the snow at the time the slope is closed may vary greatly depending upon the extent of the snow fall over the past winter and the configuration of the ground.surface.
  • the snow on the slope is pushed, preferably by machines, into a plurality of piles of snow indicated at 116 in Figs. 20, 21 and 22.
  • the location of the piles of snow on the slope will be dictated by the configuration of the slope, the depth of the snow and the judgment of the operator.
  • the piles are made as high as possible, preferably generally circular in plan and are then covered with sheets of insulating material 118 of such properties as to be capable of preserving a major portion of the snow over the summer and early autumn.
  • the snow In places where the snow is deep, it may be pushed into suitably sized piles without using all of the snow adjacently available. Where the snow cover is thin, it may be necessary to use all of the snow at that location to produce a large enough pile to survive the summer. In all cases the object is to preserve enough snow by the piling procedure plus the insulating covering to have enough snow available in the autumn which when spread on the slope will create adequate skiing conditions.
  • the area of the collected snow pile should be small in relation to the area from which the snow was collected. In other words, a high pile on a small area is preferable to a lower pile in a larger area because the percentage loss from melting is approximatley inversely proportional to the height of the pile.
  • Snow can readily be piled by machine to a height of 20 feet or more at the centre and sloping to the sides in a circular pattern.
  • a pile of snow of this character covered with suitable insulting material will lose no more than 20 to 25% of its volume over the summer.
  • suitable insulting material will lose no more than 20 to 25% of its volume over the summer.
  • Figs. 23, 24 and 25 are illustrative of the condition of the slope following distribution of the snow in the autumn from the piles 116 shown in Figs. 20, 21 and 22.
  • the lines 120 and 122 suggest the somewhat reduced width of the slope if the original depth is provided
  • Fig. 25 suggests a width of slope corresponding to boundaries 108 and 110 of Figs. 17 and 18 but with a reduced depth determined by the extent of the melting.
  • the process of accumulating the residual snow in piles in the spring and distributing it in the autumn will preferably proceed from the top to the bottom of the slope as the snow movement is aided by gravity but this process may be varied under the judgement of the machine operator.
  • the invention involves the following characteristics:-Means as claimed in any one of claims 1 to 11, wherein the snow on the ski slope that is to be utilised for said early autumnul skiing is covered in spaced areas by the insulating sheets, the uncovered parts of the slope providing crossing areas, and the quantity of snow preserved by the insulating sheets being adequate to be spread in part over the uncovered areas after removal of the insulating sheets in the autumn, thereby to provide skiing conditions over the length of the previously covered and uncovered crossing areas of the slope.
  • a method as claimed in claim 12, wherein the step of covering the snow includes covering the snow over an extended longitudinal distance with a continuous layer of the insulating material of a type capable of being wound into a continuous roll, whereby the covering may be removed from, and replaced thereon, by winding mechanisms.

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Road Paving Structures (AREA)
EP86301655A 1985-03-13 1986-03-07 Dispositif et méthode pour préserver une base de neige sur une piste de ski Withdrawn EP0201987A1 (fr)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
US71124985A 1985-03-13 1985-03-13
US711249 1985-03-13
US75401085A 1985-07-11 1985-07-11
US754010 1985-07-11
US77685585A 1985-09-18 1985-09-18
US776855 1985-09-18

Publications (1)

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EP0201987A1 true EP0201987A1 (fr) 1986-11-20

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EP86301655A Withdrawn EP0201987A1 (fr) 1985-03-13 1986-03-07 Dispositif et méthode pour préserver une base de neige sur une piste de ski

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2788228A1 (fr) * 1999-01-08 2000-07-13 Christian Lasaygues Dispositif de stockage de bache pour couvrir les terrains de tennis
AT15713U1 (de) * 2017-05-30 2018-04-15 Steinbacher Daemmstoff Ges M B H Vorrichtung zum Konservieren von Schnee
DE202018103138U1 (de) 2018-04-30 2018-06-12 Steinbacher Dämmstoff Gesellschaft m.b.H. Vorrichtung zum Konservieren von Schnee
WO2018209454A1 (fr) * 2017-05-19 2018-11-22 Suyai S.P.A. Système et procédé pour la protection des glaciers
WO2020118441A1 (fr) * 2018-12-13 2020-06-18 Glacies Technologies Inc. Ensemble d'isolation thermique flexible et procédé d'isolation thermique d'un tas de neige
WO2021005261A1 (fr) * 2019-07-10 2021-01-14 Snowsecure Oy Procédé et équipement pour fournir un stockage de neige avec isolation thermique
EP3919842A1 (fr) * 2020-06-04 2021-12-08 Serge Ferrari SAS Structure de stockage de neige et son procede de montage
US11241610B2 (en) 2016-11-07 2022-02-08 Snow Secure Oy Method for handling insulation materials used for storing snow

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB191401061A (en) * 1913-01-14 1914-05-28 Victor Tischler Improvements in Covers for Protecting Exposed Ice Surfaces.
US3870587A (en) * 1973-05-14 1975-03-11 Northrop Corp Ice Floor
US4028750A (en) * 1974-12-05 1977-06-14 Barracudaverken Aktiebolag Cover for water-filled outdoor swimming pools
US4281802A (en) * 1980-04-15 1981-08-04 T.I.C. Enterprises, Limited Thermal ice cap
FR2527465A1 (fr) * 1982-05-25 1983-12-02 Bruneteau Anita Appareil permettant le recouvrement automatique de terrains de sport, en particulier de courts de tennis
US4466143A (en) * 1983-03-01 1984-08-21 Lamb Joe H Swimming pool cover leading edge wheel assembly

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB191401061A (en) * 1913-01-14 1914-05-28 Victor Tischler Improvements in Covers for Protecting Exposed Ice Surfaces.
US3870587A (en) * 1973-05-14 1975-03-11 Northrop Corp Ice Floor
US4028750A (en) * 1974-12-05 1977-06-14 Barracudaverken Aktiebolag Cover for water-filled outdoor swimming pools
US4281802A (en) * 1980-04-15 1981-08-04 T.I.C. Enterprises, Limited Thermal ice cap
FR2527465A1 (fr) * 1982-05-25 1983-12-02 Bruneteau Anita Appareil permettant le recouvrement automatique de terrains de sport, en particulier de courts de tennis
US4466143A (en) * 1983-03-01 1984-08-21 Lamb Joe H Swimming pool cover leading edge wheel assembly

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2788228A1 (fr) * 1999-01-08 2000-07-13 Christian Lasaygues Dispositif de stockage de bache pour couvrir les terrains de tennis
US11241610B2 (en) 2016-11-07 2022-02-08 Snow Secure Oy Method for handling insulation materials used for storing snow
WO2018209454A1 (fr) * 2017-05-19 2018-11-22 Suyai S.P.A. Système et procédé pour la protection des glaciers
AT15713U1 (de) * 2017-05-30 2018-04-15 Steinbacher Daemmstoff Ges M B H Vorrichtung zum Konservieren von Schnee
DE202018102906U1 (de) 2017-05-30 2018-06-04 Steinbacher Dämmstoff Gesellschaft m.b.H. Vorrichtung zum Konservieren von Schnee
DE202018103138U1 (de) 2018-04-30 2018-06-12 Steinbacher Dämmstoff Gesellschaft m.b.H. Vorrichtung zum Konservieren von Schnee
WO2020118441A1 (fr) * 2018-12-13 2020-06-18 Glacies Technologies Inc. Ensemble d'isolation thermique flexible et procédé d'isolation thermique d'un tas de neige
WO2021005261A1 (fr) * 2019-07-10 2021-01-14 Snowsecure Oy Procédé et équipement pour fournir un stockage de neige avec isolation thermique
CN114270119A (zh) * 2019-07-10 2022-04-01 斯诺安全有限公司 用于为雪储库提供隔热的方法和装备
EP3919842A1 (fr) * 2020-06-04 2021-12-08 Serge Ferrari SAS Structure de stockage de neige et son procede de montage
FR3111186A1 (fr) * 2020-06-04 2021-12-10 Serge Ferrari Sas Structure de stockage de neige et son procédé de montage

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