JP2014055919A - Compressed snow layer formation method, and method for testing tyre on snow using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressed snow layer formation method capable of efficiently forming a compressed snow layer having desirable bulk density, desirable hardness and a desirable surface condition, and to provide a method for testing a tyre on snow using the method.SOLUTION: The method comprises: a step of preparing snow to be used for formation of a compressed snow layer; a step of controlling sealed space surrounding a compressed snow layer formation schedule surface at a prescribed temperature and humidity; a step of hydrating the snow at a prescribed rate of hydration; a step of accumulating snow up to a prescribed thickness by supplying the hydrated snow to the compressed snow layer formation schedule surface which is temperature- and humidity-controlled, within the sealed space; and a step of compressing the accumulated snow by pressing the accumulated snow from a top face toward the compressed snow layer formation schedule surface with a prescribed pressing force and freezing the water contained in the snow. The accumulation step and the snow compression step are repeated until the compressed snow layer reaches a target thickness, and thereby the compressed snow layer is formed.

Description

  TECHNICAL FIELD The present invention relates to a method for forming a snow layer and a method for testing a snow on a tire using the method, and more particularly, a method for forming a snow layer capable of efficiently forming a snow layer having a desired bulk density or a desired hardness. The present invention also relates to a method for testing a tire on snow using the method.

Conventionally, for example, a test simulating a snowy road has been performed for a tire on-snow evaluation test.
In Patent Document 1, an icing layer is formed on the inner peripheral surface of a rotating drum that can rotate around a horizontal direction, a tire is applied to the formed icing layer, and the rotating drum is rotated, whereby the ice on the tire In particular, the frozen layer consists of a fixed thickness of ice frozen water or a compressed snow layer, and various conventionally known methods can be used to form the frozen layer. It is described that there is.
In Patent Document 2, a snow layer is formed on a turntable rotatable around a vertical direction, a tire is applied to the formed snow layer, and the turntable is rotated to perform a snow test on the tire. In particular, when artificial snow made of granular water-absorbing material swollen by adding water is provided in layers, and the turntable is rotated while pressing the rolling roller against the artificial snow layer, the pressing roller is pressed. It is described that by adjusting the pressure, the artificial snow layer can be set to snow roads of various hardnesses.

In Patent Document 3, a snow-like road surface or an ice burn is formed on the surface of a loop-shaped steel belt that can rotate around a horizontal direction, and a tire is applied to the formed snow-like road surface or ice burn to form a steel belt. Rotate the tire to test the tire, and in particular, the water film formed on the steel belt is instantly frozen by the refrigerant sprayed from the refrigerant spray nozzle. It is described as possible.
Patent Document 4 discloses that an ice / snow layer is formed on the upper surface of a road surface simulation disk that can rotate around a vertical direction, a tire is applied to the formed ice / snow layer, and the road surface simulation disk is rotated, thereby Tested, especially because the water film formed on the road surface simulation disk is instantly frozen by the refrigerant gas ejected from the refrigerant spray nozzle, so that it is possible to form an ice-snow surface or an ice burn in a short time Has been.
Patent Document 5 discloses a method in which a compressed snow layer is formed on an inner peripheral surface of a cylindrical drum rotatable around a horizontal direction, a tire is applied to the formed compressed snow layer, and the cylindrical drum is rotated to rotate the tire. The slip rate or friction coefficient of the snow is measured, and it is described that the snow quality of the compressed snow road surface can be controlled as desired by controlling the temperature of water supplied to the snow gun and the room temperature of the test chamber. .

  However, the conventional method for forming a snowy road as described above has the following technical problems.

First, it is difficult to efficiently form a snow layer having a desired snow quality, particularly a desired bulk density, a desired hardness, and a desired surface state.
More specifically, Patent Document 1, Patent Document 3 and Patent Document 4 all form a freezing layer, ice / snow surface, or ice burn by forming a water film directly on the simulated road surface and freezing it. Yes, the layer itself is not frozen as a whole, for example, a snowy road formed by repeated passing of a car on a snowy road surface, in other words, a snow layer of a desired bulk density or a desired hardness is formed. It is difficult.
In this respect, Patent Document 2 is provided with artificial snow made of a granular water-absorbing material swelled by adding water instead of such a frozen layer, ice-snow surface, or ice burn, Although it is described that it is possible to set the artificial snow layer to a snow road with various hardness by adjusting the pressing force, the surface friction coefficient differs greatly from that of natural snow because of artificial snow. For example, it is difficult to properly evaluate tire slip.
On the other hand, in Patent Document 5, the pressure snow road surface formed on the inner peripheral surface of the drum body causes the snow to be injected from the nozzle of the snow gun to the inner peripheral surface while rotating the drum at a required rotation speed, and It is described that it is formed by rolling snow with a roller, and by controlling the temperature of water supplied to the snow gun and the room temperature of the test chamber, the snow quality of the snow-capped road surface is controlled as desired.
However, as a second technical problem, in the snow pressure technique according to Patent Document 5, the snow pressure layer is peeled off from the surface where the pressure snow layer is to be formed, or the snow pressure layer is cracked or cracked, and a smooth tire test is performed. It becomes difficult.

More specifically, it is possible to adjust the bulk density to a desired level by driving the snow from the snow that has been sprayed and snow accumulated by pressing the snow with a pressure roller under a predetermined temperature control. If the snow is only pressed toward the inner peripheral surface, the inner peripheral surface of the drum body and the snow and snow particles do not sufficiently adhere to each other.For example, when the compressed snow road surface is at the ceiling surface during rotation of the drum, It is difficult to perform a smooth tire test due to peeling from the peripheral surface or cracking or cracking in the snow layer. On the other hand, for example, when the moisture content is large, such as wet snow or sherbet-like snow, it is possible to suppress such peeling, cracking or cracking to some extent by increasing the snow pressure load. Is difficult to achieve.
In this regard, when natural snow falls on the road surface and, for example, a compressed snow road is formed due to its own weight or due to traffic, the bulk density increases and the sintering (firing) action gradually proceeds. In this case, the relationship between the bulk density of the snow layer and the hardness of the snow layer is approximately proportional, and the snow quality is formed as a whole. There is a need in the industry to efficiently simulate a snow-capped road independently of density and desired hardness.

JP2011-149870 JP 2001-74613 A JP 2006-208265 A JP 2006-208095 A JP2008-14667

In view of the above technical problems, an object of the present invention is to provide a method for forming a snow layer capable of efficiently forming a snow layer having a desired bulk density, a desired hardness, and a desired surface state, and a tire using the method. It is to provide a test method on snow.
In view of the above technical problems, an object of the present invention is to provide a method for forming a snow layer capable of efficiently simulating a natural snow state, and a tire on-snow test method using the method.

In order to achieve the above object, the method for forming a snow layer of the present invention comprises:
Preparing the snow to be used to form the compressed snow layer;
Managing the sealed space surrounding the formation surface of the compressed snow layer at a predetermined temperature and a predetermined humidity;
A step of adding moisture to the snow at a predetermined moisture content;
Supplying the moisture-containing snow to the formation surface of the pressure snow layer whose temperature and humidity are controlled in a sealed space, and laminating the snow with a predetermined thickness;
A step of compressing the stacked snow by freezing moisture contained in water while pressing the surface with a predetermined pressing force from the upper surface of the stacked snow toward a formation planned surface of the compressed snow layer,
The stacking step and the snow pressure step are repeated until the snow layer reaches a target thickness, thereby forming the snow layer.

According to the method for forming a snow layer of the present invention, when forming a snow layer having a target thickness using the prepared snow in a sealed space controlled at a predetermined temperature and a predetermined humidity, the water is contained at a predetermined moisture content. Use snow to limit the thickness of the compressed snow layer to be formed at a time so that the surface pressure for the compressed snow is uniformly applied to the entire thickness of the layer, and then form the compressed snow layer from the top surface of the stacked snow By pressing the surface with a predetermined pressing force toward the surface, air is expelled from the inside of the snow-capped layer, increasing the bulk density of the snow-capped layer, and actively promoting the sintering action, so It is possible to increase the hardness of the compressed snow layer by freezing the water containing water when the snow is formed and is used for bonding between the surface where the layer is to be formed, snow particles, and between the snow particles. By repeating the laminating stage and the snow pressure stage, It is possible to efficiently form a ShimegiAtsushi of compacted snow layer.

In addition, a predetermined pressing force is determined according to the bulk density required for the snow layer, and based on the determined pressing force value, a predetermined moisture content and / or pressure snow is determined according to the hardness required for the snow layer. It is preferable to further include a step of adjusting the freezing rate of moisture contained in the layer and adjusting the predetermined temperature and the predetermined humidity in the sealed space according to the freezing rate to be adjusted.
Furthermore, the preparation step includes the steps of ice making, crushing the ice made into fine ice,
The water-containing step and the laminating step use an air-feed controlled at a predetermined temperature and a predetermined humidity to pneumatically feed micro ice by a pressure-feed tube, and in the sealed space, at the outlet of the pressure-feed tube, the outlet Water should be sprayed on the fine ice flowing out of the water.
Furthermore, the preparation step and the water-containing step include ice making and spraying water on the crushed ice while crushing the ice produced,
In the laminating step, it is preferable to pneumatically feed the hydrated micro ice by a pressure feeding pipe using pressure feeding air managed at a predetermined temperature and a predetermined humidity.
In addition, the crushing step may be performed in the sealed space, and the crushed micro ice may be dropped toward the formation planned surface of the compressed snow layer and stacked.

Furthermore, the preparation step uses natural snow,
In the water-containing step and the laminating step, natural air is pneumatically fed by a pressure-feed pipe using a pressure-feed air controlled at a predetermined temperature and a predetermined humidity, while flowing in the sealed space at the outlet of the pressure-feed pipe. Water may be sprayed on natural snow flowing out from the exit.
Furthermore, the moisture content step reduces the moisture content as the snow layer is laminated from the first snow layer to be laminated on the formation surface of the snow layer, and the moisture content when forming the first snow layer is: It should be about 10%.
In addition, it is preferable that a mechanical entanglement for preventing slippage of the snow layer in the extending direction of the surface to be formed is provided on the surface to be formed of the snow layer.

Further, in the pressure snow stage, it is preferable to detect the hardness of the pressure snow layer and feedback control the pressing force with respect to the target hardness.
Furthermore, when the stacking step and the snow-pressing step are repeated, the next snow-pressing layer tends to be entangled with the surface of the snow-pressing layer formed by the immediately preceding snow-pressing step before the next snow-pressing layer is formed by the stacking step. Thus, it is preferable to have a step of forming irregularities.
In addition, it is preferable to further include a surface treatment step of polishing the upper surface of the formed snow-capped layer in a direction parallel to the upper surface in a state where the inside of the sealed space is maintained at a temperature below the freezing point.

Furthermore, the snow layer is formed on the inner peripheral surface of the inner drum that can rotate around the horizontal direction,
A sealed space formed inside the inner drum may form the sealed space.
Furthermore, by rotating the tire and / or inner drum while pressing the tire against the surface of the snow layer being formed toward the target thickness, it is used for the formation of the snow layer and on-line testing of the tire. It is good.
In addition, after forming the compressed snow layer of the target thickness, rotate the tire and / or inner drum while pressing the tire against the surface of the compressed snow layer to form the compressed snow layer and perform offline tire test It is good to use.

Furthermore, it is preferable that the method further includes a step of adjusting the temperature of the inner peripheral surface on which the snow layer is formed by adjusting the internal temperature of the inner drum.
In addition, the snow particle size is 0.2 mm to 0.3 mm, the predetermined temperature is −3 ° C. to 0 ° C., and the predetermined humidity is 80% or more.
Furthermore, the thickness of the predetermined snow layer in the stacking step may be 3 mm to 5 mm.

A first embodiment of an apparatus for forming a snow layer according to the present invention will be described below in detail with reference to the drawings.
Below, the case where the compressed snow layer forming apparatus 10 according to the present invention is applied to a snow test of a tire will be described in detail as an example.

As shown in FIG. 1 and FIG. 2, the snow-capped layer forming apparatus 10 includes a snow generating unit 16 that generates snow, a water-containing unit 18 that includes the generated snow with moisture of a predetermined moisture content, and until the snow is completed. A temperature / humidity control unit 22 for controlling the sealed space 20 surrounding the compressed snow layer forming surface 11 to a predetermined temperature and a predetermined humidity, and the wet snow in the sealed space 20 so that the moisture in the wet snow does not freeze. A snow pressure feeding unit 24 for pressure feeding toward the layer forming surface 11; a snow pressure unit 26 for applying a predetermined pressure from the upper surface 27 of the snow layer stacked on the snow layer forming surface 11 toward the snow layer forming surface 11; A relative movement unit 19 that performs relative movement between the forming surface 11 and the snow pressure unit 26 is schematically configured.

The compressed snow layer forming surface 11 has a linear shape extending in the longitudinal direction, and the compressed snow layer forming device 10 accumulates snow on the upper surface so as to compress the snow. The casing 21 has a casing 21 disposed so as to cover the upper surface from above, and the casing 21 has an opening that opens downward, and in the casing 21, snow is accumulated on the compressed snow layer forming surface 11 to compress the snow. It is composed.
More specifically, the snow layer forming apparatus 10 is self-propelled, for example, by a relative movement unit 19 whose driving source is a hydraulic or electric motor, and each unit is connected to or fixed to the casing 21. 21 is configured to be relatively movable in the longitudinal direction of the compressed snow layer forming surface 11 with respect to the compressed snow layer forming surface 11 by a roller 12 and a relative movement unit, and 19, while the casing 21 is moving, the compressed snow layer in the inside thereof. Snow is accumulated on the forming surface 11 to compress the snow.

A curtain 23 is provided at the lower part of each longitudinal front and rear surface of the compressed snow layer forming surface 11 of the casing 21 so as to stroke the compressed snow layer formed surface 11 so that the inside of the casing 21 is further sealed.
The upper surface of the casing 21 is penetrated by a transport pipe of the snow generation unit 16, a water supply pipe of the water-containing unit 18, and an air conditioning air supply pipe of the temperature / humidity control unit 22, which will be described later. The pipes are fixedly supported, and these pipes are flexible. When the compressed snow layer forming apparatus 10 moves in the longitudinal direction of the compressed snow layer forming surface 11, the movement of the compressed snow layer forming apparatus 10 is hindered. Each has a sufficient length.

As shown in FIG. 2, the casing 21 is covered with a vinyl sheet 25 from above, so that the inner space of the casing 21 is made a substantially sealed space, and the temperature and humidity control unit 22 to be described later sets the inner space to a predetermined temperature and It is easy to maintain at a predetermined humidity, so that it becomes possible to efficiently form a snow layer of a desired snow quality on the snow layer forming surface 11, as will be described later. By covering the compressed snow layer forming surface 11 in the respective directions before and after the compressed snow layer forming apparatus 10 is located with a vinyl sheet 25, temperature and humidity can be easily maintained.

As shown in FIG. 3, the snow generating unit 16 includes a snow hopper 40, a feeder 42 as a snow supply means is provided at the lower portion of the hopper, and the feeder 42 has a flexible nozzle having an ejection nozzle 43 at the tip. A snow carrying pipe 17 is connected, and the snow in the feeder 42 is sent to the carrying pipe 17 by wind from a blower 46 which is a pneumatic feeding means whose air flow is controlled by an inverter, and the snow blows out by the carrying air. 43 is conveyed.

The water-containing unit 18 includes a water tank 58, and water in the tank is supplied from the water supply pipe 61 to the ejection nozzle 43 by a pump 59. The moisture content unit 18 further includes a moisture content control unit 50. The moisture content control unit 50 includes a layer thickness detecting means 52 for the snow layer L, a hardness detecting means 54 for the snow layer L, the detected layer thickness and The supply amount adjusting means 56 adjusts the supply amount of water according to the hardness. The supply amount adjusting means 56 uses a flow meter 63 provided in the water supply pipe 61 to control the supply amount of water to the nozzle by the pump 59. Adjust by controlling.
In FIG. 1, two transport pipes 17 are provided, both of which supply the generated snow and water to be contained in the snow by the configuration of FIG.
Incidentally, the pumping of water may be performed not with the pump 59 but with compressed air. In this case, it is preferable to adjust the supply amount of the water by adjusting the pressure of the air for supplying the pressure by supplying the pressure air from the compressor to the gas phase portion of the sealed water tank 58 and sending the water to the nozzle.

As shown in FIG. 4 (C), the water spray 43 for spraying water onto the fine ice particles flowing out from the ejection opening 33 of the transport pipe 17 uniformly mixes snow and water, and the required moisture content from the tip. The water spray 43 is arranged so as to inject water when the snow is diffused by the diffusion swash plate 75 provided opposite to the ejection opening 33.
The water spray 43 sprays water in a diffusing manner toward the snow flow of the snow particles before the snow particles diffused by the inclined surface 74 before the snow accumulation on the target snow surface. A mixed space of the snow fountain flow and the fountain flow is formed above.

As a modified example, as shown in FIG. 4 (A), an appropriate number of water blowing pipes 60 spaced apart from each other in the circumferential direction of the transport pipe 17 are arranged on the outer circumference of the cylinder toward the extension line of the cylinder axis. It may be configured to spray the spray water onto the snow from the cylindrical body and eject it as snow particles, or as shown in FIG. 4 (B), water spray around the ejection opening 33 of the transport pipe 17. Without providing 43, the water spray 43 may be arranged so as to inject water against the snow ejected from the ejection opening 33.

In FIG. 1, unlike the water spray 43, the water spray 48 does not inject water toward the snow particles flowing out from the transport pipe 17, but directs the water toward the top surface of the snow that accumulates on the compressed snow layer forming surface 11. Thus, as will be described later, when a snow layer having a predetermined thickness is further formed on the snow layer having a predetermined thickness formed on the snow surface forming surface 11, the bonding property between these snow layers is determined. To ensure.
A cyclone portion 66 described later may be provided on the upstream side of these water sprays 43.
As a modification, according to the water spray 48 that is a one-fluid nozzle, the water droplet diameter increases, which may cause uneven snow quality. According to this, it is possible to generate a minute mist (water droplet), there is little dripping, and the water droplet diameter and spray amount can be adjusted by a combination of air pressure and water pressure. There is.

A pressure air temperature / humidity controller (not shown) for adjusting the temperature and humidity of the pressure air is further provided so that the temperature and humidity in the sealed space 20 are not disturbed by the pressure air flowing into the sealed space 20. Thus, the temperature and humidity in the sealed space 20 can be easily controlled by the temperature and humidity control unit 22.
For example, when the snow particle size is 0.2 mm to 0.3 mm, the predetermined temperature in the sealed space 20 is −10 ° C. to 0 ° C., and the predetermined humidity is 60% or more, more preferably It is −3 ° C. to 0 ° C. and 80% or more, and if it is out of this range, it will be difficult to sufficiently exhibit the adhesive effect of water to be contained in the snow as will be described later regardless of the snow quality. . Here, the snow particle size means the most frequent particle size in weight ratio when expressed by particle size distribution.

As shown in FIG. 5, the snow pressure feeding unit 24 has a cyclone portion 66 on the front end side of the conveying pipe 17 that pneumatically feeds the snow particles, and the snow particles are placed on the conveying air to reach the compressed snow layer forming surface 11. However, the carrier air and the snow particles are partly separated by a cyclone method so as not to disturb the snow particles accumulated on the compressed snow layer forming surface 11.

More specifically, a solid-gas separation space 68 that extends in the vertical direction and separates into solid and gas is formed in the cyclone portion 66. The solid-gas separation space 68 has a tapered shape, for example, a conical shape, so as to easily generate a swirling flow. The solid-gas separation space 68 is provided in the cyclone portion 66 in the conveyance space of the conveyance pipe 17. Is formed so that the solid particles can form a swirling flow so that the gas such as the carrier air can be separated from the solid particles such as ice and snow by centrifugal force from the ice and snow pressure-fed by the carrier air. . In addition, an inlet 70 connected to the transport pipe 17 is formed on the upper side surface of the cyclone unit 66, and the inflow port 70 is connected to the cyclone unit 66 by the ice and snow fed by the carrier air as carrier air. Both are provided so as to be taken into the solid-gas separation space 68.

Below the cyclone portion 66, an ice / snow discharge port 72 is provided so as to open downward (downward in the figure). That is, the cyclone portion 66 has an ice / snow discharge port 72 formed by the cyclone portion 66. It is provided so that solid particles such as separated snow and ice can be discharged to the outside. The cyclone portion 66 is provided with an air extraction pipe 69 for taking out a gas such as carrier air separated by the cyclone portion 66 so as to penetrate the upper portion of the cyclone portion 66 through the center of the cyclone portion 66. An extraction port 71 and an air supply port 73 are formed at the end of the air extraction pipe 69. Among these, the extraction port 71 of the air extraction pipe 69 opens downward (downward in the figure) in the solid-gas separation space 68 of the cyclone portion 66, and the extraction port 71 is the inlet of the cyclone portion 66. It is formed below 70. In addition, the part which the air extraction pipe | tube 69 penetrated the cyclone part 66 is penetrated and provided so that an airtight state may be maintained.

In particular, the air extraction pipe 69 is provided with an adjustment valve 67, and by adjusting the opening of the adjustment valve 67, the ratio of the carrier air discharged from the ice / snow discharge port 72 is adjusted. It is possible to partially separate the discharged ice particles and the carrier air. More specifically, when the regulating valve 67 is fully opened, the ice particles and the carrier air are completely separated. It becomes difficult to supply the grains to the pressure snow layer forming surface 11. On the other hand, if the regulating valve 67 is fully closed, the ice grains and the carrier air are not separated at all and are discharged from the ice snow discharge port 72. When the accumulated air on the compressed snow layer forming surface 11 is disturbed by the transported air and irregularities are formed on the snow covered surface, the degree of opening of the adjustment valve 67 is appropriately adjusted to thereby adjust the snow on the compressed snow layer formed surface 11. The ice particles, the carrier air, and the carrier air can be supplied to the compressed snow layer forming surface 11 using the carrier air discharged from the ice / snow outlet 72 while preventing the snow accumulation from being disturbed. , Partly separated.

The snow particles are transported by air transport in the transport pipe 17, and the outflow opening of the cyclone portion 66 connected to the downstream side of the transport pipe 17 is arranged at a predetermined distance H from the compressed snow layer forming surface 11. Is made to reach the snow-snow layer forming surface 11 from the outlet by a jet of carrier air.
The snow particles are dry snow, the particle diameter is 0.2 mm to 0.3 mm, and the outflow opening of the cyclone portion 66 is disposed within 1 meter from the snow layer forming surface 11.
By adjusting the conveyance speed of the carrier air according to the size of the particle of the snow particles and the maximum diameter of the swirl flow of the snow particles in the cyclone unit 66, the cyclone unit method can carry the carrier air, the snow particles, A part is separated.

As shown in FIG. 6, an inclined surface 74 is provided in the inside so as to be opposed to the ejection opening 33 of the conveyance pipe 17 that pumps snow particles downward toward the ejection opening 33 by the conveyance air. The surface 74 is configured such that a snow flow of snow particles ejected from the ejection opening 33 collides with the inclined surface 74, so that the snow flow diffuses on the pressure snow forming surface 11 at a level below the ejection opening 33 and accumulates snow. In addition, the direction is inclined by a predetermined angle α with respect to the direction of snow particle ejection.

The inclined surface 74 has a size such that the inclined surface 74 includes a projection area on the inclined surface 74 in the direction of inclining the predetermined angle α, and in the ejection direction of the snow particles of the ejection opening 33. . As a result, all the snow particles ejected from the ejection opening 33 collide with the inclined surface 74 and reliably diffuse. As a result, before the snow particles diffused by the inclined surface 74, the water nozzle 42 sprays water in a diffused manner toward the snow flow of the snow particles before the target snow surface is accumulated, thereby the target snow surface. A mixed space of the fountain flow and the fountain flow is formed above.

The ejection opening 33 is circular, and the inclined surface 74 is constituted by the upper surface 27 of the inclined disk 75 supported by the conveying pipe 17. The upper surface 27 is difficult to snow-fix, for example, by Teflon processing. A curved surface portion 76 that is concave toward the bottom surface, and a flat surface portion 80 that is continuously and smoothly connected to the lower end 78 of the curved surface, and is disposed so as to extend downward from the curved surface portion 76 toward the flat surface portion 80. The side on which the curved surface portion 76 is provided is a delayed side in the direction in which snow is scattered while being diffused by the inclined surface 74.
In particular, when dry snow with a moisture content of 0%, approximately 1-20% wet snow, approximately 21-95% sherbet, snow, approximately 96% or more snow water, if dry snow, As shown in FIG. 6A, the inclined surface 74 having only the flat surface portion 80 without the curved surface portion 76 may be used. On the other hand, in the case of wet snow or sherbet, as shown in FIG. The inclined surface 74 having the curved surface portion 76 and the flat surface portion 80 is preferable. In any case, as shown in FIG. 6C, all the snow particles ejected from the ejection opening 33 collide with the inclined surface 74. Therefore, it is possible to further diffuse and expand the snow accumulation area on the pressure snow forming surface 11 before reaching the pressure snow forming surface 11.

As shown in FIG. 6D (a cross-sectional view taken along line AA in FIG. 6C), the thickness D of the diffusion region is determined by the initial ejection speed of the snow particles and the mixing ratio of the snow particles and the carrier air. In particular, it is possible to obtain a desired diffusion effect by adjusting the mixing ratio after ensuring the initial ejection speed of the snow particles at a predetermined speed or higher. In this case, when the gap between the ejection opening 33 and the pressure snow forming surface 11 is close, the influence of the carrier air on the pressure snow forming surface 11 is strong, and there is a possibility that the snow accumulation on the pressure snow forming surface 11 may be disturbed, the cyclone portion The carrier air flowing out from the ice / snow discharge opening 72 may be reduced by increasing the opening of the adjustment valve 67 by 66.
The inclined disk 75 is supported by the transport pipe 17 via the rod-shaped member 80. The rod-shaped member 80 has an upper end connected to the transport pipe 17 and extends substantially on the central axis of the transport pipe 17, and a lower end 78 connected to the center of the inclined disk 75, whereby the inclined disk 75 is transported Supported by a tube 17. Thus, when the snow particles are ejected from the ejection opening 33, the rod-shaped member 80 is not hindered.
The inclined disk 75 is arranged concentrically with the transport pipe 17 and is rotatable around a vertical direction passing through the center of the inclined disk 75, so that the target snow cover of the snow particle eruption flow is achieved. The diffusion region 82 for the surface may be changed continuously.
Further, as a modified example, as described above, when it is desired to diffuse the snow radially by the inclined disk 75 instead of diffusing the snow in a certain direction, a conical surface is used instead of the inclined disk 75, for example. May be provided.

As shown in FIGS. 7 and 8, the snow pressure unit 26 has a snow pressure load plate 85, and this snow pressure load plate 85 is supported by the casing 21 and faces the upper surface 27 of the snow accumulated on the snow pressure layer forming surface 11. The surface contact part 84 which can contact, and the press part 86 which presses the surface contact part 84 toward the snow-capped layer formation surface 11 are provided.
The surface contact portion 84 has a plate shape, the width is slightly narrower than the width of the casing 21, and the contact surface that comes into contact with the snow-snow layer L is made of a material that is difficult to snow, or is processed. Level determining means 88 for the layer forming surface 11 is provided.

The surface contact portion 84 includes a snow pressure portion 90 formed along the shape of the pressure snow layer formation surface 11 and a contact surface when the surface contact portion 84 is leveled with respect to the pressure snow layer formation surface 11 by the level determining means 88. And a guide portion 92 that is curved so that the distance from the snow pressure layer forming surface 11 gradually narrows toward the snow pressure portion 90 and that is continuously and smoothly connected to one end of the snow pressure portion 90.
As shown in FIG. 7, the compressed snow portion 90 is formed along the shape of the compressed snow layer forming surface 11, and when the compressed snow layer forming surface 11 is planar as shown in FIG. As shown in FIG. 7 (B), when the compressed snow layer forming surface 11 is concave, it is concave. When the compressed snow layer forming surface 11 is convex as shown in FIG. 7 (C), it is convex.
Further, the pressing portion 86 is configured to urge the snow pressure portion 90 toward the snow pressure layer forming surface 11 by a spring 87 as shown in FIG. 1, whereby the level determining means 88 causes the snow pressure layer forming surface 11. Using the surface contact portion 84 that has been leveled with respect to the snow, the relative movement unit 19 passes the snow stacked on the snow pressure layer forming surface 11 through the guide portion 92, and is guided by the guide portion 92, while the snow pressure portion 90. Compress the stacked snow.

The guide portion 92 has a curved shape and / or material and / or plate thickness that can smoothly guide the stacked snow to the snow pressure portion 90, and is a material that is at least more flexible than the snow pressure portion 90.
The surface contact portion 84 further includes a solid main body portion 94 on the side opposite to the contact surface of the plate portion, and the solid main body portion 94 gradually increases in hardness from the guide portion 92 to the snow pressure portion 90. . Therefore, for the solid main body portion 94, for example, the guide portion 92 is made of sponge or rubber from the guide portion 92 toward the snow pressure portion 90, while the snow pressure portion 90 is made of a metal material. Good.
The curved shape may be a sine wave shape for one wavelength including a valley and a peak.

Further, as shown in FIG. 9, in the state where the inside of the sealed space 20 is maintained at a temperature below the freezing point, irregularities are formed on the upper surface 27 of the formed snow layer L so that the next snow layer L is easily entangled. Means are provided. Specifically, the rotating brush 101 and a detecting means 103 for detecting the upper surface 27 of the snow layer L to determine the level of the rotating brush 101 are provided, and the detecting means 103 and the rotating brush 101 are connected. Thus, the rotation of the rotary brush 101 forms irregularities on the upper surface 27 of the snow pressure layer L so that the next snow pressure layer L is easily entangled with the surface of the formed snow pressure layer L.
As shown in FIG. 10, a mechanical entanglement portion 98 that prevents the snow-capped layer L from sliding in the extending direction of the snow-capped layer forming surface 11 is provided. Specifically, as shown in FIGS. 10 (A) and 10 (B), a large number of elongated projection members each having a hook portion at the upper end portion are provided on the snow-snow layer forming surface 11, or as shown in FIG. 10 (C). Thus, it is preferable to provide an uneven portion that extends in the direction intersecting the longitudinal direction of the surface of the compressed snow layer forming surface 11. This prevents slippage between the lower surface of the compressed snow layer L and the compressed snow layer forming surface 11 when the snow cover on the compressed snow layer forming surface 11 is compressed by the compressed snow load plate 85, and the snow accumulation is ensured. It is made to guide to the pressure snow load board 85. The height h of the elongated protrusion member or the uneven portion may be determined from this viewpoint.

Furthermore, in order to adjust the internal temperature of the inside drum 12, it further has an internal temperature adjusting means (not shown), thereby adjusting the temperature of the inner peripheral surface 14 on which the snow layer L is formed.
As a modification, as shown in FIG. 11, an ice breaker 25 is provided in the sealed space 20, and the ice pieces transferred to the sealed space 20 by the transfer pipe 17 are crushed into an ice breaker 25 having a rotary feeder, and the rotary feeder is used. The generated ice particles may be dropped directly toward the compressed snow formation surface 11. In this case, since it is possible to prevent the conveyance air from reaching the pressure snow forming surface 11, the cyclone portion 66 may not be provided in the conveyance pipe 17.

A method for forming a snow layer using the snow layer forming apparatus having the above-described configuration will be described in detail below with reference to the drawings while describing a snow test on a tire.
First, the following steps are performed in order to form a snow layer on the snow layer forming surface 11.

As shown in FIG. 12, the formation method of the compressed snow layer includes a snow making process (step 1) for compressing snow, a temperature and humidity management process (step 2) for the space where the formed snow is accumulated, and the snow was made. A pressure-feeding step (step 3) for pumping snow to a surface where a snow-snow layer is to be formed in the space, a water-containing step for adding water before the snow is formed (step 4), and a snow-covering step for placing the water-containing snow on the inside drum (step 4) Step 5), a snow pressure process (Step 6) for compressing snow that has accumulated snow, and whether or not the snow layer has reached the desired thickness, and if not, perform a pumping process, a water-containing process, a snow accumulation process, and a snow pressure process. By repeating the steps, a compressed snow layer having a desired thickness is formed, and a surface treatment process (step 7) for surface-treating the upper surface of the formed compressed snow layer is roughly constituted.
Each step will be described in detail below. In addition, the compressed snow layer forming apparatus 10 is configured to perform the pressure feeding process, the water-containing process, the snow accumulation process, and the snow pressure process while moving along the longitudinal direction of the compressed snow layer forming surface 11 by the relative movement unit 19. The speed may be determined from this viewpoint.

In step 1, the snow generation unit prepares snow to be used for forming the compressed snow layer. More specifically, for example, ice making is performed, and the formed ice is crushed to form fine ice having a predetermined particle size (0.2 mm to 0.3 mm).
In step 2, the sealed space 20 surrounding the snow-capped layer forming surface 11 is managed at a predetermined temperature and a predetermined humidity. The predetermined temperature is −10 ° C. to 0 ° C., and the predetermined humidity is 60% or more, more preferably −3 ° C. to 0 ° C., 80% or more.

In step 3, the snow particles made of fine ice are conveyed into the sealed space 20 by the pressurized air via the conveying pipe 17 guided into the sealed space 20.
In this case, the transport air and the snow particles are partly separated by the cyclone portion 66 at the tip of the transport pipe 17, so that the snow in the snow is not disturbed by the transport air on the compressed snow layer forming surface 11. I have to.
Specifically, the cyclone method creates a swirling flow by centrifugal force on the snow particles that are transported by air, so that the transport air and the snow particles are partially separated, and the snow particles ride on the transport air and pressurize snow. While reaching the layer formation surface 11, the snow particles accumulated on the pressure snow layer formation surface 11 are not disturbed, so that the accumulated snow on the pressure snow layer formation surface 11 is not rolled up by the carrier air, and the efficiency is improved on the pressure snow layer formation surface 11. It is possible to snow.

Further, when the partially separated snow particles are ejected from the ejection opening 33, the snow particles are diffused in the lateral direction of the ejection direction by colliding with the diffusion swash plate, and the snow snow layer forming surface 11 is spread over a wide range. It is possible to accumulate snow without any bias.
Specifically, when the snow particles are pumped downward toward the ejection opening 33 by the carrier air in the transportation pipe 17, when the inclined surface 74 is disposed so as to face the ejection opening 33, the inclined surface 74 is In the inclined surface 74, the inclined surface 74 includes a projection region on the inclined surface 74 in the direction of injecting the snow particles in the inclined surface 74, with the direction inclined by the predetermined angle α with respect to the snow particle ejecting direction. By making the size as described above, when the snow particles pumped by the conveying air in the conveying pipe 17 are ejected from the ejection opening 33, the snow particles are surely collided with the inclined surface 74. Depending on the inclination angle α of the inclined surface 74 with respect to the direction of snow particle ejection, the snow particles diffuse before reaching the target snow surface at a level below the ejection opening 33, so that the snow is efficiently distributed on the target snow surface. It is possible to accumulate snow uniformly. Noh.

In step 4, the moisture unit 18 hydrates the snow with a predetermined moisture content.
As shown in FIG. 13, in this water-containing stage, the moisture content is reduced as the first snow layer is formed from the first snow layer to be stacked on the surface where the snow layer is to be formed. The rate is preferably about 10%. Thereby, at the beginning of the snow accumulation process, by increasing the water content, the surface tension of the water improves the adhesion between the snow layer forming surface 11 and the snow, and decreases to about 3% as the snow accumulation process proceeds. Let
In FIG. 13, at a timing t that is reduced to about 3%, the moisture content is initially about 10% in order to sufficiently adhere the first snow layer to the snow layer forming surface 11. If the mechanically entangled portion (see FIG. 10) of the formation surface 11 is hidden by snow, it is judged that the first snow layer and the snow layer formation surface 11 are completely bonded, and at least necessary to maintain the adhesion between the snow particles. From the viewpoint of realizing a desired snow quality, the moisture content is reduced to about 3%.
More specifically, before the diffused snow particles accumulate on the compressed snow layer forming surface 11 which is the target snow accumulation surface, water is sprayed in a diffused manner toward the snow particles from the water nozzle 43, thereby injecting the snow particles. Since it is possible to uniformly hydrate the snow flow, and it is not necessary to increase the water pressure of the water jet according to the pumping degree of the carrier air, it is possible to generate snow with a desired moisture content, It is possible to efficiently accumulate snow having a desired water content that is uniformly water-containing.

In step 5, the wet snow is supplied to the formation surface 11 of the pressure-snow layer whose temperature and humidity are controlled in the sealed space 20, and the snow is laminated with a predetermined thickness. The thickness of the predetermined snow layer in one stacking step is 3 to 5 mm, and this is repeated to form a predetermined thickness.
In this case, in the water-containing stage and the stacking stage, the fine ice is pneumatically fed by the pressure feed pipe using the pressure feed air controlled to the predetermined temperature and the predetermined humidity, and in the sealed port 20 at the jet outlet 33 of the transport pipe 17. Then, water is sprayed on the ice particles flowing out from the ejection port 33.

In step 6, the laminated snow is compressed by freezing moisture contained in water while pressing with a predetermined pressing force from the upper surface of the stacked snow toward the compressed snow layer forming surface 11. In the snow pressure stage, the hardness of the snow pressure layer is detected, and the pressing force is feedback-controlled with respect to the target hardness.
In this case, the solid main body portion 94 gradually increases in hardness from the guide portion 92 to the snow pressure portion 90, and the distance between the guide portion 92 and the snow pressure layer forming surface 11 gradually increases toward the snow pressure portion 90. Therefore, when the stacked snow reaches between the guide portion 92 and the compressed snow layer forming surface 11 by the relative movement unit 19, slippage between the compressed snow layer formed surface 11 occurs. The guide portion 92 is smoothly guided toward the snow-capped portion 90 without causing resistance.

At that time, until the compressed snow is completed, the moisture content is controlled so that it does not freeze. For example, the temperature of the snow surface at the outlet of the compressed snow plate is measured by a non-contact temperature sensor (infrared radiation thermometer). The air temperature is controlled so that the temperature here is -1 to 0 ° C. While the contact-type measurement space described later is a point, non-contact has a surface average temperature of a circle with a diameter of several hundreds of millimeters, so that non-contact suppresses uneven snow quality on the entire snow surface.
Alternatively, the use of a contact-type temperature sensor decreases accuracy but is inexpensive. Further, there is a method by measuring a dielectric constant. The dielectric constant equation is a method of measuring the moisture content from the dielectric change according to the amount of water in the snow, and according to this, it can be determined whether or not the freezing has been completed. In addition, it does not need to be completely frozen at the pressure snow outlet, and it is only necessary that the moisture contained before the snow is re-frozen is frozen.

In this case, since the mechanically entangled surface that prevents the compressed snow layer from slipping in the extending direction of the surface to be formed is provided on the compressed snow layer forming surface 11, the compressed snow layer does not slip, and the compressed snow load plate 85 And the pressure snow layer forming surface 11, and the surface pressure is applied by the pressure snow load plate 85 to expel air from the pressure snow layer, increase the bulk density of the pressure snow layer, and actively promote the sintering action It is possible to utilize the water containing water for adhesion between the snow layer forming surface 11 and the snow particles and between the snow particles.
Until the compressed snow layer reaches the target thickness, the stacked snow layer forming device 10 is returned to the initial position again by the relative movement unit 19 to repeat the stacking step and the compressed snow step, thereby forming the compressed snow layer. When repeating the stacking step and the snow pressure step, before the next snow layer is formed by the stacking step, the rotating brush is used so that the next snow layer is easily entangled with the surface of the snow layer formed by the immediately preceding snow layer. In addition to forming unevenness by 101, water is sprayed on the surface of the snow layer by the water spray 48 so that the next snow layer is easily attached.

A predetermined pressing force is determined according to the bulk density required for the snow layer, and based on the determined pressing force value, a predetermined moisture content and / or pressure snow is determined according to the hardness required for the snow layer. It is also possible to adjust the freezing rate of moisture contained in the layer and adjust the predetermined temperature and the predetermined humidity in the sealed space according to the freezing rate to be adjusted.
In step 7, surface treatment is performed so that the upper surface of the formed snow layer is polished in a direction parallel to the upper surface while the inside of the sealed space is maintained at a temperature below the freezing point. Thereby, for example, it is possible to simulate a road surface that substantially reproduces a friction coefficient of a so-called smooth road surface.
This completes the formation of the compressed snow layer.

        In this case, by covering the compressed snow layer forming unit 10 from above with the vinyl sheet 25, the sealed space 20 in the compressed snow layer forming unit 10 can be easily maintained at a constant temperature and a constant humidity, Even if the relative movement unit 19 causes the compressed snow layer forming unit 10 to move in a self-propelled manner relative to the compressed snow layer formed surface 11 along the longitudinal direction of the compressed snow layer formed surface 11, because of the flexibility of the vinyl sheet 25, Only the portion of the vinyl sheet 25 around the moving snow layer forming unit 10 is raised, and the other portions of the vinyl sheet 25 are substantially flat, and this raised portion can move smoothly and The compressed snow layer forming surface 11 in the longitudinal direction in which the layer forming unit 10 is located is also covered with the vinyl sheet 25. DOO are possible, generally, while relatively moving along the compacted snow layer forming unit 10 in the longitudinal direction of the compacted snow layer forming surface 11, it is possible to complete the snow and groomed to compacted snow layer forming surface 11.

When the snow layer is formed by the above steps, the snow layer is formed by rotating the tire and / or the inner drum while pressing the tire against the surface of the snow layer being formed toward the target thickness. And use it online for testing snow on tires. The test tire is a tire filled with a required air pressure with a wheel rim, and a support shaft is inserted into the shaft hole of the wheel rim.
In this case, by adjusting the internal temperature of the inner drum, the temperature of the inner peripheral surface on which the snow layer is formed is adjusted.
Note that measurement data detected by a load cell (not shown) is output to an arithmetic processing unit (not shown), where the measurement data is taken into a storage circuit and processed for processing under various conditions. Slip rate, friction coefficient μ
The calculation processing device may be provided with a measurement result display means (not shown) for displaying the result of the calculation processing.

According to the above method for forming a snow layer, when forming the snow layer of the target thickness using the prepared snow in the sealed space 20 controlled at a predetermined temperature and a predetermined humidity, the water is contained at a predetermined moisture content. Use snow to limit the thickness of the compressed snow layer to be formed at a time so that the surface pressure for the compressed snow is uniformly applied to the entire thickness of the layer, and then form the compressed snow layer from the top surface of the stacked snow By pressing the surface with a predetermined pressing force toward the surface 11, air is expelled from the inside of the snow layer, and the bulk density of the snow layer is increased, and the sintering action is actively promoted, so It is possible to increase the hardness of the compressed snow layer by freezing the water containing water when it is used for bonding between the formation surface 11 of the compressed snow layer, the snow particles, and the snow particles, and when the compressed snow is completed. Repeat the laminating and snow-pressing stages. Accordingly, it is possible to a compacted snow layer of target thickness is efficiently formed.

The second embodiment of the present invention will be described in detail below. In the following description, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted, and the features of the present embodiment will be described in detail.

The feature of the apparatus for forming a snow layer according to the present embodiment is that a snow layer is formed on the inner peripheral surface of the inside drum 12 that can rotate around the horizontal direction, and accordingly, the procedure for forming the snow layer is slightly different. .
More specifically, the compressed snow layer forming apparatus 10 is disposed in the inner space of the inside drum 12 that can rotate around the horizontal direction, forms the compressed snow layer L on the inner peripheral surface 14 of the inside drum 12, and is formed. In the state where the tire is pressed against the upper surface 27 of L, the inside drum 12 is rotated around the horizontal direction so that the on-snow test of the tire is performed.

As shown in FIG. 14, the inside drum 12 has a cylindrical shape, a drum holding unit 28 that holds the drum so as to be rotatable about a horizontal axis P <b> 1, and a drum rotation driving unit 30 attached to the drum holding unit 28. The test tire holding portion that supports the test tire rotatably around the horizontal axis while bringing the outer peripheral surface of the test tire into contact with the pressure snow layer forming surface formed on the inner peripheral surface 14 of the drum body 32 with a predetermined load. 34 and a tire rotation driving unit 36 attached to the tire holding unit.

The drum is made of steel, and includes a drum main body 32 having a smooth inner peripheral surface 14 and a disk-shaped back wall 38 that closes one end surface of the drum main body 32, the other end surface being an opening, and the peripheral edge of the opening. Is provided with an inner flange portion, the opening is covered with, for example, a vinyl sheet 25, and the inside of the inside drum 12 is used as a sealed space.
As shown in FIG. 15, the sealed space formed inside the inside drum 12 constitutes the sealed space 20, and the snow-capped layer forming unit 10 is disposed in the sealed space 20.

As described above, in the first embodiment, the snow layer forming apparatus 10 is self-propelled and moves relative to the snow layer forming surface to thereby remove snow accumulated on the snow layer forming surface 11. In contrast to the snow pressure, in the present embodiment, the inside snow drum forming device 10 is fixed inside the inside drum 12 and the inside drum 12 itself is provided with the snow snow forming surface 11 on the inner peripheral surface. By rotating around the horizontal direction, the snow accumulated on the inner peripheral surface is compressed.
According to such a configuration, compared to the first embodiment, the inside of the inside drum 12 can be used without intentionally providing a sealed space that is a temperature and humidity management space. When 11 is used for the on-snow test of the tire, it is not always necessary to provide the compressed snow layer forming surface 11 in a flat shape. Therefore, the space for providing the compressed snow layer forming surface 11 is larger than the configuration in which the compressed snow layer formed surface 11 extends in the longitudinal direction. Can be greatly reduced.

  The procedure for forming the compressed snow layer using the inside drum 12 is generally the same as that of the first embodiment. When the inside drum 12 is covered with snow over the entire inner peripheral surface, and then is compressed, the inside drum 12 The snow may be pressed while laminating continuously while rotating, and the snow may be stacked, or the inside drum 12 may not be rotated and the snow may be stacked while being pumped against a portion of the inner peripheral surface. Then, the inside drum 12 may be rotated to compress the snow, and then a similar operation may be repeated on a new portion of the inner peripheral surface to form a snow-pressed surface on the entire inner peripheral surface.

In this case, in the case where it is desired to prevent a seam from forming in the compressed snow layer formed on the inner peripheral surface of the inside drum 12, the former procedure is preferable, and the snow quality of the compressed snow layer is discontinuous in terms of bulk density or hardness. The latter procedure is preferable when it is desired to simulate the state.
In particular, in the latter case, the snow pressure treatment may be performed after stacking several millimeters of snow on the inner peripheral surface of the inside drum 12, and the snow accumulation and the snow pressure may be repeated again, or only the snow pressure is intermittently performed. You may go to

The embodiments of the present invention have been described in detail above, but various modifications or changes can be made by those skilled in the art without departing from the scope of the present invention.
For example, in the present embodiment, the apparatus for forming a snow-capped layer has been described as applied to a tire on-snow test. As far as importance is attached, the sliding friction test is related to winter shoes slip prevention test, skiing, snow boat sliding test, or mobile test using sledge in cold region, without snow pressure process and water content When using it as a technique to spread snow that has been covered, there is a phenomenon in which wet snow on a railroad is rolled up as a railway vehicle travels as a wet snow application, and the rolled up snow adheres to the vehicle. If the snow is peeled off and collides with the rear part, or if it collides with stones laid on the railroad, the stones are repelled and the stones are damaged at the rear part, or the snow damage is caused by the stones colliding with the opposing car. That ballast phenomenon) place, there is a possibility that can be used for this test.

For example, in the present embodiment, the compressed snow layer forming apparatus 10 performs the pumping process, the water-containing process, the snow accumulation process, and the snow pressure process while being moved along the longitudinal direction of the compressed snow layer forming surface 11 by the relative movement unit 19. However, the present invention is not limited to this, and when the compressed snow layer forming apparatus 10 reaches a predetermined position in the longitudinal direction of the compressed snow layer forming surface 11 by the relative movement unit 19, it is temporarily stopped there, and the pumping process, water-containing process, snow accumulation If the process and the snow-crushing process are performed and these processes are completed, the movement of the snow-capped layer forming apparatus 10 may be started and repeated.

For example, in the present embodiment, the case where artificial snow such as ice particles is used to form a compressed snow layer has been described. However, the present invention is not limited to this, and natural snow may be used. Artificial snow may be used.
For example, in the present embodiment, it has been described that the single snow pressure load plate 85 is provided inside the inside drum 12, but is not limited thereto, and along the inner peripheral surface of the inside drum 12, A plurality of snow-loading load plates 85 may be provided at a predetermined angular interval from each other, and the snow accumulation may be compressed by each of the snow-loading load plates 85.
For example, in the present embodiment, after the compressed snow layer L having the target thickness is formed, the tire and / or the inside drum 12 is rotated while pressing the tire against the surface of the compressed snow layer L, thereby Although it has been described that it is used for the formation and off-line snow test of the tire, it is not limited thereto, and it may be used for the formation of the compressed snow layer L and on-line tire on-snow test.

1 is an overall view of a compressed snow layer forming system according to a first embodiment of the present invention. It is a partial schematic diagram of the temperature and humidity management unit of the compressed snow layer forming system according to the first embodiment of the present invention. It is a partial schematic diagram of a snow generation unit of a compressed snow layer formation system concerning a 1st embodiment of the present invention. It is a partial schematic diagram of the water-containing unit of the snow-capped layer forming system according to the first embodiment of the present invention. It is a partial schematic diagram of the cyclone part of the snow conveyance unit of the compressed snow layer forming system according to the first embodiment of the present invention. It is a partial schematic diagram of the diffusion swash plate of the snow transport unit of the compressed snow layer forming system according to the first embodiment of the present invention. It is a partial detail drawing of the snow-carrying load board of the snow-carrying unit of the snow-capped layer forming system according to the first embodiment of the present invention. It is a partial detail drawing of the snow-crushing unit of the snow-capped layer formation system which concerns on 1st Embodiment of this invention. FIG. 3 is a partial detailed view conceptual diagram of a surface treatment unit for a snow-capped layer in the snow-capped layer forming system according to the first embodiment of the present invention. It is a partial detail drawing of the snow peeling prevention member provided in a snow-capped layer formation surface in the snow-capped layer formation system which concerns on 1st Embodiment of this invention. It is the partial schematic of the modification of the snow production | generation unit of the compressed snow layer formation system which concerns on 1st Embodiment of this invention. It is a flowchart for the formation procedure of the snow-capped layer by the snow-capped layer forming system according to the first embodiment of the present invention. It is a graph which shows the time change of the moisture content by the moisture unit of the compressed snow layer formation system which concerns on 1st Embodiment of this invention. FIG. 6 is a partial detail view around an inside drum of a snow layer formation system according to a second embodiment of the present invention. It is a figure similar to FIG. 1 of the compressed snow layer formation system which concerns on 2nd Embodiment of this invention.

T Test tire L Snow layer S Snow particle 10 Snow layer forming device 11 Snow layer forming surface 12 Inside drum 13 Roller 14 Inner peripheral surface 16 Snow generating unit 17 Transport pipe 18 Water-containing unit 19 Relative moving unit 20 Sealed space 21 Casing 22 Temperature and humidity Control unit 23 Curtain 24 Snow pressure feeding unit 25 Crusher 26 Snow pressure unit 27 Upper surface 28 Drum holding unit 30 Drum rotation driving unit 32 Drum main body 34 Test tire holding unit 36 Tire rotation driving unit 38 Rear wall 40 Snow hopper 42 Feeder 43 Ejection nozzle 45 Inverter 46 Blower 48 Water spray 50 Water content control unit 52 Layer thickness detection means 54 Hardness detection means 56 Water supply amount adjustment means 58 Water tank 59 Pump 63 Flow meter 66 Cyclone section 67 Adjustment valve 68 Solid gas separation space 69 Air extraction Tube 71 Extraction port 3 Air supply port 74 Inclined surface 75 Inclined disk 76 Curved surface portion 80 Flat portion 80 Bar member 82 Diffusion region 85 Snow pressure load plate 87 Biasing means 88 Level adjusting means 90 Snow pressure portion 93 Snow surface detecting portion 92 Curved guide portion 94 Solid Main unit 98 Entangling unit 101 Rotating brush 103 Detection means

Claims (17)

Preparing the snow to be used to form the compressed snow layer;
Managing the sealed space surrounding the formation surface of the compressed snow layer at a predetermined temperature and a predetermined humidity;
A step of adding moisture to the snow at a predetermined moisture content;
Supplying the moisture-containing snow to the formation surface of the pressure snow layer whose temperature and humidity are controlled in a sealed space, and laminating the snow with a predetermined thickness;
A step of compressing the stacked snow by freezing moisture contained in water while pressing the surface with a predetermined pressing force from the upper surface of the stacked snow toward a formation planned surface of the compressed snow layer,
A method for forming a snow-capped layer, comprising: repeating the stacking step and the snow-capping step until a snow-capped layer reaches a target thickness, thereby forming the snow-capped layer.         A predetermined pressing force is determined according to the bulk density required for the compressed snow layer, and based on the determined pressing force value, the predetermined moisture content and / or the compressed snow layer is determined according to the hardness required for the compressed snow layer. The method for forming a compressed snow layer according to claim 1, further comprising a step of adjusting a freezing rate of moisture containing water and adjusting a predetermined temperature and a predetermined humidity in the sealed space according to the adjusting freezing rate. The preparation step includes the steps of ice making, crushing the ice made into fine ice,
The water-containing step and the laminating step use an air-feed controlled at a predetermined temperature and a predetermined humidity to pneumatically feed micro ice by a pressure-feed tube, and in the sealed space, at the outlet of the pressure-feed tube, the outlet The method for forming a compressed snow layer according to claim 1 or 2, wherein water is sprayed on the fine ice flowing out from the water. The preparation step and the water-containing step include ice making and spraying water on the crushed ice while crushing the ice produced,
3. The method for forming a compressed snow layer according to claim 1, wherein the laminating step pneumatically feeds water-containing micro ice by a pressure feeding tube using pressure feeding air managed at a predetermined temperature and a predetermined humidity.         5. The method for forming a compressed snow layer according to claim 3, wherein the crushing step is performed in the sealed space, and the crushed micro ice is dropped toward a formation planned surface of the compressed snow layer and stacked. The preparation stage uses natural snow,
In the water-containing step and the laminating step, natural air is pneumatically fed by a pressure-feed pipe using a pressure-feed air controlled at a predetermined temperature and a predetermined humidity, while flowing in the sealed space at the outlet of the pressure-feed pipe. The method for forming a compressed snow layer according to claim 1 or 2, wherein water is sprayed on the natural snow flowing out from the outlet. The moisture content step reduces the moisture content as the snow layer is laminated from the first snow layer to be laminated on the formation surface of the snow layer, and the moisture content when forming the first snow layer is about 10%. The method for forming a snow layer as claimed in claim 1 or 2. The method for forming a snow-capped layer according to claim 1, wherein the formation surface of the snow-capped layer is provided with mechanical entanglement that prevents the snow-capped snow layer from sliding in the extending direction of the surface to be formed. The method for forming a snow-capped layer according to any one of claims 1 to 8, wherein in the snow-crushing step, the hardness of the snow-capped layer is detected and the pressing force is feedback-controlled with respect to the target hardness.         When repeating the laminating step and the snow pressure step, before forming the next snow layer by the laminating step, the surface of the snow layer formed by the immediately preceding snow layer is easily entangled with the next snow layer, The method for forming a snow-capped layer according to claim 1, comprising a step of forming irregularities.         2. The method for forming a snow-capped layer according to claim 1, further comprising a surface treatment step of polishing the upper surface of the formed snow-capped layer in a direction parallel to the upper surface in a state where the inside of the sealed space is maintained at a temperature below the freezing point. The snow layer is formed on the inner peripheral surface of the inner drum that can rotate around the horizontal direction.
The method for forming a snow-capped layer according to any one of claims 1 to 11, wherein a sealed space formed inside the inner drum forms the sealed space.         The tire and / or inner drum is rotated while pressing the tire against the surface of the snow layer being formed toward the target thickness, and is used for on-snow testing of the tire by forming the snow layer and on-line. The method for forming a snow-capped layer according to 12.         After forming the snow layer with the target thickness, rotate the tire and / or inner drum while pressing the tire against the surface of the snow layer to form the snow layer and use it for off-line testing of the tire offline. The method for forming a snow layer as claimed in claim 12.     The method for forming a snow-capped layer according to claim 13 or 14, further comprising adjusting a temperature of an inner peripheral surface on which the snow-capped layer is formed by adjusting an internal temperature of the inner drum.     2. The formation of a snow-capped layer according to claim 1, wherein the snow particle size is 0.2 mm to 0.3 mm, the predetermined temperature is −3 ° C. to 0 ° C., and the predetermined humidity is 80% or more. Method.     The method for forming a snow-capped layer according to claim 1, wherein a thickness of the predetermined snow layer in the stacking step is 3 mm to 5 mm.

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