JP2015172481A - Snow accumulation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a snow accumulation method capable of efficiently and uniformly accumulating snow on a target snow accumulation face.SOLUTION: A snow accumulation method comprises the steps of: downwardly pressure feeding snow particles toward a jet opening 33; spreading jet snow particle flow such that the jet snow particle flow ejected from the jet opening 33 includes a lateral component, which is to a downward component, via physical collisions together with the downward component; allowing snow particles to include water by injecting water in a diffusion state into the spread-jet snow particle flow before the snow accumulating step; and uniformly accumulating the spread-jet snow particle flow on a target snow accumulation face at a level lower than that of the jet opening 33.

Description

  The present invention relates to a snow accumulation method, and more particularly to a snow accumulation method capable of snow accumulation uniformly and efficiently on a target snow accumulation surface.

Conventionally, a snow layer is simulated using artificial snow or natural snow, and various tests, for example, on-snow tests of tires, have been performed using this snow layer.
In such tests, the snow quality of snow is important, and it is classified into dry snow, wet snow, sherbet snow, and snow water according to the moisture content of the snow. In order to generate the water, the water is added to the snow on the target snow surface, or the water is added before the snow is accumulated.

For example, Patent Documents 1 and 2 disclose a technique for adding water to such snow.
In Patent Document 1, a plurality of water injection nozzles that are circumferentially spaced around the ejection openings are provided around the ejection openings by pumping snow particles toward the ejection openings by the carrier air in the conveyance pipe. The water is jetted toward the snow flow of snow particles.
According to such water-containing technology, since water is contained in the ejection opening, for example, when sherbet snow is generated in advance and transported in the transport pipe, the snow and water are separated and the snow and water are uniformly mixed However, it is possible to eliminate such a problem and generate a sorbet flow of sherbet snow in which snow and water are mixed to some extent uniformly.

However, such water-containing technology has the following technical problems.
First, the momentum of the carrier air that pumps the snow particles is used as it is to create a snow flow of snow particles, which makes it difficult to uniformly accumulate snow on the target snow surface.
In more detail, since snow is accumulated in a state where the squirting flow of snow particles is not sufficiently diffused, the snow accumulation location is unevenly distributed on the target snow accumulation surface, or in some cases, a lump of snow is generated, and Unevenness is formed on the upper surface. Such a situation hinders an appropriate test when, for example, a snow test of a tire is performed using a snow layer on a target snow surface.

Secondly, it is difficult to generate snow having a desired moisture content uniformly containing water, and a certain part is accumulated on the target snow accumulation surface in a wet snow state and a certain part in a dry snow state.
More specifically, since the snow particles are pumped by the carrier air, when water is jetted at the jet opening, in order to mix the jet of water with the snow jet of the snow particles, the pressure of the carrier air is used. Accordingly, it is necessary to increase the water pressure accordingly, and in the case of snow having a low water content, it is difficult to uniformly contain water.

In this regard, in Patent Document 2, a water injection nozzle that pumps snow particles toward the ejection opening by the conveyance air in the conveyance pipe and injects water toward the snow flow of the snow particles ejected from the ejection opening is provided. ing.
According to such a water-containing technique, since water is contained at a position away from the ejection opening, unlike Patent Document 1, it is possible to uniformly generate snow having a desired water content, but it is diffused in all directions. Since water is jetted to the snow flow of the snow particles in a state of being made, it is difficult to efficiently generate water-containing snow.
In particular, when performing various tests using snow accumulated on the target snow surface, for example, on-snow tire tests, snow having a desired snow quality, that is, a desired moisture content, is required to efficiently perform an appropriate test. It is desired that snow be efficiently accumulated on the target snow surface.
Japanese Patent No. 4289776 JP-A-6-323710

In view of the above technical problems, an object of the present invention is to provide a snow accumulating method capable of accumulating snow uniformly and efficiently on a target snow accumulating surface.
In view of the above technical problems, an object of the present invention is to provide a snow accumulating method capable of efficiently accumulating snow having a desired water content uniformly containing water.

In order to achieve the above object, the snow accumulation method of the present invention comprises:
Pumping snow particles downward toward the spout opening;
A snow flow of snow particles ejected from the ejection opening, along with a downward component through a physical collision,
Diffusing a snow flow of snow particles so as to have a lateral component with respect to the downward direction;
Before the snow accumulation stage, water is sprayed in a diffused manner against the snow flow of the spreading snow particles,
A stage of hydrating snow particles;
A step of causing the snow flow of the diffused snow particles to uniformly accumulate on a target snow surface at a level below the ejection opening.

Embodiments of a snow accumulating unit and a snow accumulating method according to the present invention will be described below in detail with reference to the drawings.
Below, the case where the snow accumulating unit according to the present invention is applied to a tire on-snow test will be described in detail as an example.
The snow accumulated by the snow accumulation unit can be either artificial snow or natural snow. Good.

In particular, in the case of artificial snow, for example, ice pieces that have been made may be crushed to form ice particles having a predetermined particle size, and snow may be accumulated.
On the other hand, the target surface on which the snow accumulates is the inner peripheral surface of the inside drum that can rotate around the horizontal direction. Using the snow that has accumulated on the inner peripheral surface, the test tire is applied to the snow accumulating surface, The tire is tested on the snow by rotating around the direction.

More specifically, the snow accumulating unit 10 is disposed in the internal space of the inside drum 12 that can rotate in the horizontal direction, forms a snow layer L on the inner peripheral surface 14 of the inside drum 12, and an upper surface 27 of the formed snow layer L. The tire T is tested on the snow by rotating the inside drum 12 around the horizontal direction with the tire T pressed against the tire T.

As shown in FIG. 1, in the tire testing apparatus, the inside drum 12 has a cylindrical shape, a drum holding portion 28 that holds the drum rotatably around a horizontal axis P <b> 1, and a drum attached to the drum holding portion 28. The test tire T can be rotated around the horizontal axis while the outer peripheral surface of the test tire T is brought into contact with the rotation driving unit 30 and the snow-capped road surface 11 formed on the inner peripheral surface 14 of the drum body 32 with a predetermined load. A test tire holding portion 34 to be supported and a tire rotation driving portion 36 attached to the tire holding portion are provided.

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, and the other end surface is an opening, An inner flange portion is provided along the opening, the opening is covered with, for example, a vinyl sheet 25, and the inside of the inside drum 12 is a sealed space 20.
The sealed space formed inside the inside drum 12 constitutes the sealed space 20, and the snow accumulating unit 10 is disposed in the sealed space 20.
As shown in FIG. 2, the snow accumulating unit 10 includes a transport pipe 17 provided with a cyclone portion 66 at the front end, a diffusion swash plate 75 provided facing the ejection opening 33 of the transport pipe 17, and the transport pipe 17. A water jet nozzle 43 arranged in the vicinity of the jet opening 33 is generally configured.

As shown in FIG. 2, a cyclone portion 66 is provided on the tip side of the transport pipe 17, and the snow particles piled on the planned snow accumulation surface 11 are disturbed while the snow particles are carried on the transport air and reach the planned snow accumulation surface 11. The carrier air and snow particles are partly separated by a cyclone method to the extent that they are not.

More specifically, as shown in FIG. 2, 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 conical shape, for example, which is tapered toward the ice / snow discharge port 72 so that a swirling flow is likely to be generated inside. The solid-gas separation space 68 is formed in the cyclone portion 66. It is formed so that these solid particles can form a swirling flow so that gas such as carrier air can be separated from solid particles such as ice and snow by centrifugal force from ice and snow pumped by carrier air in the conveyance space. ing. Further, an inlet 70 connected to the transport pipe 17 is formed on the upper side surface of the cyclone section 66. The inlet 70 is connected to the cyclone section 66 by the ice and snow fed by the transport air together with the transport air. The solid-gas separation space 68 can be taken in.

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. In addition, 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 degree of the adjustment valve 67, the ratio of the conveyance air discharged from the ice / snow discharge port 72 is adjusted and discharged from the ice / snow discharge port 72. It is possible to partially separate the generated 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. Then, the carrier air discharged from the ice / snow discharge port 72 is used to remove the ice particles from the planned snow cover surface. However, if the regulating valve 67 is fully closed, the ice particles and the carrier air are not separated at all, and the carrier air discharged from the ice / snow outlet 72 causes the snow on the planned snow accumulation surface 11. When the snow cover is disturbed and irregularities are generated on the snow cover surface, the snow on the planned snow cover surface 11 is not disturbed by appropriately adjusting the opening of the adjusting valve 67, and is discharged from the ice snow discharge port 72. The ice particles are partially separated from the carrier air so that the ice particles can be supplied to the planned snow cover surface 11 using the carrier air.

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 from the planned snow accumulation surface 11 to flow the snow particles. It reaches the snow-covered planned surface 11 by a jet of carrier air from the outlet.
When the snow particles are dry snow and the particle size is, for example, 0.2 mm to 0.3 mm (the most frequent particle size by weight ratio in the particle size distribution), the snow flows through the outflow opening of the cyclone unit 66. Place within 1 meter from the planned surface 11.
The carrier air and the snow particles are partially separated by the cyclone method by adjusting the carrier air conveyance speed in accordance with 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. .

As shown in FIG. 3, the diffusing inclined plate 75 is provided with an inclined surface 74 disposed so as to face the ejection opening 33 of the transport pipe 17 that pumps snow particles downward. The snow particles so that the snow flow of the snow particles ejected from the ejection opening 71 collides with the inclined surface 74, so that the snow flow diffuses on the pressure snow forming surface 11 below the ejection opening 71 and accumulates snow. The direction is inclined at a predetermined angle α with respect to the jet direction.
When the inclined surface 74 is inclined at a predetermined angle α, the inclined surface 74 has a size such that a projected area of the ejection opening 71 on the inclined surface 74 in the direction of snow particle ejection is included in the inclined surface 74. As a result, all of the snow particles ejected from the ejection opening 71 collide with the inclined surface 74 and reliably diffuse.

The ejection opening 71 is circular, and the inclined surface 74 is constituted by the upper surface 27 of the inclined disk 75 supported by the transport pipe 17. The upper surface 27 is difficult to snow-fix, for example, by Teflon processing. A curved surface 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 it is classified as dry snow having a moisture content of 0%, wet snow of about 1 to 20%, sherbet snow of about 21 to 95%, snow water of about 96% or more, in the case of dry snow, FIG. As shown in FIG. 3A, 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 snow, as shown in FIG. An inclined surface 74 having a flat surface portion 80 is preferable, and in any case, as shown in FIG. 3C, all of the snow particles ejected from the ejection opening 33 collide with the inclined surface 74 and are reliably diffused. By reaching the formation surface 11, it is possible to further diffuse and expand the snow accumulation area on the pressure snow formation surface 11.

As shown in FIG. 3D (a cross-sectional view taken along line AA in FIG. 3C), the diffusion region thickness D depends on 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 planned snow cover surface 11 is close, the influence of the carrier air on the snow cover planned surface 11 is strong, and the snow cover on the snow cover planned surface 11 may be disturbed, the cyclone unit 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 diffusing inclined plate 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 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 connected to the transport pipe 17. 17 is supported. 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 disposed concentrically with the transport pipe 17 and is rotatable about a vertical direction passing through the center of the diffusing inclined plate 75, so that the target snow accumulation surface of the snow flow of snow particles The diffusion region 82 may be continuously changed.

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 placed 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.

The effect | action is demonstrated below about the snow accumulating unit 10 which has the above structure.
First, prepare snow to be used for snow accumulation. More specifically, for example, ice is made, and the ice that has been made is crushed into fine ice having a predetermined particle size.
Next, the sealed space surrounding the planned snow cover surface is managed at a predetermined temperature and a predetermined humidity. When the snow particle diameter 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.

Next, snow particles made of fine ice are conveyed into the sealed space by the compressed air through the conveying pipe 17 guided into the sealed space.
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.

Specifically, the cyclone method generates a swirling flow by centrifugal force with respect to 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 are expected to accumulate snow. 11, while preventing the snow particles accumulated on the planned snow accumulation surface 11 from being disturbed, the snow accumulation on the planned snow accumulation surface 11 is not rolled up by the carrier air, and the snow accumulation surface 11 can be efficiently covered with snow. Is possible.

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 diffusing inclined plate 75, and the snow accumulation surface 11 covers a wide range. It is possible to accumulate snow without any bias.

Specifically, as shown in FIG. 2, when the snow particles are pumped downward toward the ejection opening 33 by the transportation air in the transportation pipe 17, the inclined surface 74 is arranged to face the ejection opening 33. When the inclined surface 74 is oriented in a direction inclined by a predetermined angle α with respect to the snow particle ejection direction, the projection area of the ejection opening 33 on the inclined surface 74 in the snow particle ejection direction of the ejection opening 33 is By setting the size so as to be included in the inclined surface 74, when the snow particles pumped by the conveying air in the conveying pipe 17 are ejected from the ejection opening 33, the snow-blown flow of the snow particles is surely inclined. Since the snow particles are diffused by reaching the target snow surface below the ejection opening 33 according to the inclination angle α of the inclined surface 74 with respect to the ejection direction of the snow particles. Efficient and uniform snow accumulation on the snow surface It is possible to make it.

Next, the water spray 43 is used to hydrate the snow with a predetermined moisture content.
Specifically, before the diffused snow particles accumulate on the planned snow accumulation surface 11, the water spray 43 sprays water toward the snow particles in a diffusive manner, thereby uniformly containing the snow particles. In addition, since 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, and the desired moisture content that is uniformly contained It is possible to accumulate snow at a high rate efficiently.

Next, in the sealed space 20, the wet snow is supplied to the planned snow cover surface 11 which is temperature and humidity controlled, and the snow is laminated with a predetermined thickness.
In this case, in the water-containing stage and the stacking stage, the fine ice is pneumatically fed by the transport pipe 17 using the compressed air controlled at a predetermined temperature and predetermined humidity, and the spout 33 of the transport pipe 17 is provided in the sealed space 20. Then, water is sprayed on the fine ice flowing out from the ejection port 33.
Further, the snow layer is pressed toward the inner peripheral surface from above, for example, so that the snow layer is not peeled off from the inner peripheral surface by the rotation of the inside drum 12 and then formed toward the target thickness. The tire T and / or the inside drum 12 is rotated while pressing the tire T against the surface of the inside snow-snow layer, thereby forming the snow-snow layer and utilizing the tire T on the snow test online. The test tire T is a tire T with a wheel rim and filled with a required air pressure, and a support shaft is inserted into the shaft hole of the wheel rim.

According to the snow accumulating unit 10 having the above configuration, when the snow particles are pumped downward toward the ejection opening 33 by the transport air in the transport pipe 17, the inclined surface 74 is arranged to face the ejection opening 33. When the inclined surface 74 is oriented in a direction inclined by a predetermined angle α with respect to the snow particle ejection direction, the projection area of the ejection opening 33 on the inclined surface 74 in the snow particle ejection direction of the ejection opening 33 is By setting the size so as to be included in the inclined surface 74, when the snow particles pumped by the conveying air in the conveying pipe 17 are ejected from the ejection opening 33, the snow-blown flow of the snow particles is surely inclined. Since the snow particles are diffused by reaching the target snow surface 11 below the ejection opening 33 according to the inclination angle α of the inclined surface 74 with respect to the ejection direction of the snow particles. On target snow cover 11 It is possible to accumulate snow efficiently and uniformly.

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 case has been described where snow is ejected vertically below the planned snow accumulation surface 11 by the transport pipe 17, but the present invention is not limited thereto, and may be obliquely downward.
For example, in the present embodiment, the shape of the diffusing inclined plate 75 has been described as a circular shape, but is not limited thereto, and may be determined according to the shape of the ejection opening 33 of the transport pipe 17. A non-circular shape may be used as long as the projection area onto the inclined surface in the direction in which the snow particles are ejected has a size that is included in the inclined surface.

For example, in the present embodiment, the description has been made on the case where the snow cover is used for the on-snow test of the tire T. However, the present invention is not limited to this. For example, it is a snowfall simulation by dropping icy snow from the ceiling, adhesion to local areas such as cars and railways, snow penetration test, vehicle wiper test, snow entrance test at the front part, vehicle It may be used for sensor tests, air conditioning air suction tests, snow accretion tests, and spray tests on the back of the vehicle bottom. (Collision force) can be adjusted.

For example, in the present embodiment, it has been described that the snow is diffused by the swash plate for diffusion and then water is added to the snow. However, the present invention is not limited to this. Alternatively, the water injection nozzle may be used for the surface treatment of the upper surface by supplying water to the upper surface of the formed snow layer, or may be used in combination.

1 is a schematic view of a tire testing apparatus that uses a snow accumulation unit according to an embodiment of the present invention. It is the schematic of the snow accumulating unit which concerns on embodiment of this invention. It is a partial detail drawing of the inclination board for diffusion of the snow accumulating unit concerning the embodiment of the present invention. It is a partial detail drawing of the water injection nozzle of the snow accumulating unit which concerns on embodiment of this invention.

T Test tire S Snow particles 10 Snow accumulation unit 11 Planned snow accumulation surface 12 Inside drum 14 Inner peripheral surface 17 Transport pipe 20 Sealed space 28 Drum holder 30 Drum rotation drive unit 32 Drum body 34 Test tire holding unit 36 Tire rotation drive unit 38 Rear surface Wall 66 Cyclone portion 67 Control valve 68 Solid gas separation space 69 Air extraction pipe 71 Extraction port 73 Air supply port 74 Inclined surface 75 Inclined disk 76 Curved surface portion 80 Flat surface portion 80 Bar-shaped member 82 Diffusion region

Claims (1)

Pumping snow particles downward toward the spout opening;
A snow flow of snow particles ejected from the ejection opening, along with a downward component through a physical collision,
Diffusing a snow flow of snow particles so as to have a lateral component with respect to the downward direction;
Before the snow accumulation stage, water is sprayed in a diffused manner against the snow flow of the spreading snow particles,
A stage of hydrating snow particles;
And a step of causing the snow flow of the diffused snow particles to uniformly accumulate on a target snow surface at a level lower than the ejection opening.

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