JP2002138417A - Blowing-off type snow protection fence - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the visibility of a driver by enhancing the blowing-off effect of a blowing-sweeping type snow protection fence. SOLUTION: A plurality of blade type snow protection boards 13 are inclined and installed among supports 12 disposed upright along the windward side edge of a road 1 at intervals vertically so that the blowing sides are heightened. The sectional shape of the blade type snow protection board 13 is formed in a downward projected shape. Since a wind passing among the snow protection boards 13 blows down at an angle smaller than the angles of inclination θof the snow protection boards, the angles of inclination of the snow protection boards 13 can be set large, and seeing-through through the snow protection boards of the driver can be improved, enhancing shielding properties and blowing-off properties. The projected area of the wind direction is reduced, wind load can be lightened, there is no possibility of the blowing-off of the snow protection boards 13 and the overturning moment of the supports 12 is decreased. Since lift P towards a windward lower section is generated in the snow protection boards, the effect of the prevention of the blowing-off of the snow protection boards is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is installed along a road in a snowy area, and blows off snow on the road using wind.
Also, the present invention relates to a blow-off type snow fence that prevents visibility from being impaired by snow.

[0002]

2. Description of the Related Art As a snow-proof fence installed along a road in a snow-covered area, for example, as shown in FIG. There is a blow-off type snow protection fence 4 in which the mold snow protection plate 3 is attached at an interval up and down and inclined so that the wind blowing side (the left side in FIG. 12) is higher. The blow-off snow fence 4 deflects the wind passing through the gap between the upper and lower wing-shaped snow shields 3 into an obliquely downward flow and blows it down onto the road surface. It blows off the snow that has accumulated on the windshield and pushes down the snow flying from the windward to the driver's (vehicle driver's) eye level height h = 1.35 m or less, thereby preventing the driver from obstructing visibility.

[0003] In this type of conventional snow blower fence 4 of the type, the shape of the wing-shaped snow cover 2 is upwardly convex as shown in the drawing (Japanese Patent Application Laid-Open No.
0-338909, and Japanese Utility Model Application Laid-Open No. 62-38916). In addition, there is also a mere flat snow protection plate, and a wing-shaped snow protection plate having a blowing side convex upward and a blowing side convex downward (see JP-A-10-292319). There is no one having a downwardly convex shape, and at least one having a downwardly convex shape on the wind blowing side is not used. This is because when the wind in the horizontal direction is deflected downward by the wing-shaped snowboard to obtain a downward wind (blowing wind), the wing-shaped snowboard must be raised This is because a convex wing shape is a common sense and natural idea.

[0004]

However, in the conventional wing type snow protection plate 2 which is convex upward, as shown in FIG. 12, the blowing wind hits the road surface, bounces strongly, and the snow on the road soars, and the visibility is reduced. It is easy to be defective, and the driver's line-of-sight height h =
There is a problem that the visibility around 1.35 meters is not good. Although such a problem will be described later in detail together with the case of the present invention, it is shown in FIG. 9 which is a photograph of a conventional blow-off type snow fence 4 during a smoke tunnel experiment. Further, if the blowing wind bounces strongly on the road surface, the horizontal speed cannot be maintained at a long distance, so that the blowable distance L is short. In this type of snow blow fence of this type, the driver can view the scenery outside the fence through the gap between the wing-shaped snow shields 3. Has a large projected area in the horizontal direction and a small gap between the wing-shaped snow protection plates 3, so that the driver's visibility over the snow protection fence is not good.

[0005] Further, in the case of an upwardly convex wing-shaped snowboard, a lift is generated in the leeward upward direction similar to the lift acting on the wings of the airplane. There is a possibility that the load acts and the wing-shaped snowboard is detached from the column and blown off.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks. The present invention can increase the blowable distance over which snow on a road surface can be blown off, and can cause a driver to lose visibility. Can be prevented, and
It is an object of the present invention to provide a blow-off type snow fence in which a driver has a good prospect of passing through a snow fence and is not likely to blow off a wing type snow protection plate by wind.

[0007]

According to the present invention, there is provided a snow blow-off fence according to the present invention, which comprises a plurality of wing-shaped snow-prevention plates interposed between pillars standing at intervals along the windward side edge of a road. Are mounted at an interval vertically and inclined so that the blowing side becomes higher, and the cross-sectional shape of the wing type snowproof plate is formed to be convex downward.

A second aspect of the present invention is the blow-off type snow fence of the first aspect, wherein the inclination angle θ of the wing type snow protection plate is set to be smaller at higher places.

According to a third aspect of the present invention, in the blow-off type snowproof fence of the first aspect, the wing type snowproof plate has a hook portion bent downward on an outer surface of a side plate fixed to both ends of the snowproof plate body, The hook portion is fitted into the cylindrical receiving portion provided on the support member, the hook portion is prevented from coming off, and the hook portion is attached to the support.

According to a fourth aspect of the present invention, the left and right hook portions of the wing type snow protection plate are different from each other in the blow-off type snow protection fence of the third aspect.

According to a fifth aspect of the present invention, in the blow-off type snowproof fence of the first aspect, the wing-shaped snowproof plate is bent downward at a plurality of locations in the width direction of the single plate to have a downwardly convex shape. It is characterized by.

According to a sixth aspect of the present invention, in the blow-off type snow fence according to the first or fifth aspect, the wing type snow protection plate has a cross-sectional shape in which an upper edge thereof is folded upward and a lower edge thereof is folded downward. I do.

[0013]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIGS. FIG. 1A is a simplified front view showing one span portion of a blow-off snow fence 11 according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA of FIG. As shown in the drawing, the blow-off type snow fence 11 of this embodiment is shown.
Is, for example, four wing-shaped snowproof plates 13 are vertically spaced between the columns 12 erected along the road 1 on the windward side of the road 1 (to the left of FIG. 1B). And the blowing side (Fig. 1
(Left side in (b)).

In the present invention, the wing type snow protection plate 13 has a downwardly convex shape as shown in the figure. As shown in detail in FIGS. 3 and 4, the wing type snow protection plate 13 of the embodiment has a configuration in which side plates 16 are fixed to both ends of a snow protection plate main body 15 having a downward convex shape. Has a downwardly convex shape by sequentially bending a plurality of portions in the plate width direction. The side plate 16
Is a bracket 16 having the same cross-sectional shape as the snowproof plate body 15.
The end of the snow-proof plate main body 15 is fastened to the bracket 16a with bolts 17 and nuts. Also, as shown in FIG. 5, on the outer surface of the side plate 16,
One end of a 90 ° elbow 18a is provided with a downwardly bent hook portion 18 to which a small-diameter short pipe 18b is welded and fixed, while a U-shaped member 19a is welded and fixed at a predetermined angle θ to the column 12 side. Part 19 is formed, and the wing type snowproof plate 13 is formed.
Side hook portion 18 is fitted into the cylindrical receiving portion 19,
The retaining pin 20 is used for retaining the wing-shaped snow plate 13.
Is attached to the support 12. The size (outer diameter) of the short pipe 18b of the left and right hook portions 18 of the wing type snowproof plate 13
Are different from each other, and the sizes of the right and left U-shaped members 19a are also changed according to the short pipe 18b to be fitted. Thereby, it is possible to reliably prevent a mistake in which the wing type snowproof plate 13 is mounted left and right reversed, that is, a mistake in which the wing type snowproof plate 13 is mounted in a state of being turned upside down and convex.

FIG. 2 shows a specific example of the blow-off snow fence 11 of the embodiment. The strut 12 is made of H-shaped steel, and has a strut leg portion 12 a welded and fixed on the base plate 22 and a strut body portion 12 to which the wing-shaped snowproof plate 13 is attached.
The lower end of the support body 12b is rotatably connected to the support leg 12b by a hinge 12c. The holding portion 2 for storing and holding the wing-shaped snow protection plate 13 in the summer when the blow-off type snow protection fence 11 is not used, in the support leg portion 12b.
3 are provided. In the summer, each wing-shaped snowboard 13 is supported
2 and held by the holding portion 23, and the support body 12
b is bent at a right angle by a hinge 12c, and the snow blow fence 1
1 is folded so as not to obstruct the driver's view. 24 is an anchor bolt embedded in concrete. As shown in FIG. 5, the U-shaped member 19a forming the cylindrical receiving portion 19 is welded and fixed to a mounting plate 25 which is welded and fixed in a flange portion of the column 12 made of H-shaped steel. The angle θ of the cylindrical receiving portion 19 becomes the inclination angle θ of the wing type snow protection plate 13. In addition, the support 12
Are connected by a connecting member 26. The dimensions of each part of the snow blow-off fence 11 of the embodiment are fence height H = 3.4.
m, the length of the wing type snow plate 13 is 3.73 m, and the wing type snow plate 1
The height of the snowboard body 15 of the third is 0.5 m, the interval between the upper and lower wing-shaped snowboards 13 is 0.64 m, and the height position of the lowermost wing-shaped snowboard 13 is 1.15 m. The cross-sectional shape of the wing type snowproof plate 13 is the shape shown in FIG. As will be described later, the blow-off snow fence used in the wind tunnel experiment is a quarter model of this size.

The principle of operation of the wing type snow protection plate 13 in the blow-off type snow protection fence 11 will be described.
Is small, the shielding performance (the action of the wing-shaped snow protection plate 13 to block the wind) is enhanced, and the downward wind is strengthened.
Is large, the shielding property is reduced, and the downward wind is weakened. Therefore, the inclination angle θ is adjusted for each of the wing-shaped snow protection plates 13, the inclination angle θ is reduced in high places, and the inclination angle θ is increased in low places, so that the shielding property is improved and blowing is performed far away. The payment effect can be maintained. Therefore, as shown in FIG. 1B, the angle (inclination angle) θ of each of the four stages of the wing-shaped snowproof plates 13 with respect to the support 12 is set to be the maximum at the lowermost stage, and to be smaller at the upper stage.

The results of wind tunnel experiments performed on the snow blow fence of the present invention and the conventional snow blow fence of the present invention will be described. For the blow-off snow fence of the present invention, a smoke tunnel experiment and a large wind tunnel experiment were performed, and for the conventional snow blow fence, only a smoke tunnel experiment was performed. In the large wind tunnel experiment, a blow-off type snow fence (however, a 1/4 scale model of the size described above) was installed in the wind tunnel, and the horizontal wind speed behind the blow-off type snow fence was measured by a hot wire anemometer.
As the conventional snow blown fence of the present invention, the snow blow fence 11 of the embodiment of the present invention in which the wing type snowproof plate 13 of the blown snow fence 11 is installed upside down is used.

FIG. 8 is a photograph of a blow-out type snow fence 11 of the present invention at the time of a smoke tunnel experiment, and FIG. 9 is a photograph of a conventional blow-off type snow fence at the time of a smoke tunnel experiment. It can be seen that in the conventional method, the wind passing through the wing-shaped snowboard blows strongly against the road surface and bounces, whereas in the case of the present invention, such a phenomenon does not occur. Note that the double circle visible in the photograph is not directly related to the items described in this specification (description omitted).

FIG. 7 shows the results of a wind tunnel experiment on the blow-off snow fence 11 of the present invention. The horizontal axis represents the dimensionless speed which is the ratio to the speed of the wind applied to the snow blow fence 11, and the vertical axis represents the wind speed. The ratio (Y / H) of the measured height position Y to the fence height H (= 3.4 meters). The position at which the wind speed was measured was X = 0.61 as the separation distance X from the blowing snow fence 11.
H, X = 1.21H, X = 1.82H, X = 2.42
H, X = 3.03H, X = 3.64H, X = 4.24
H, X = 4.61H at eight positions, each having a dimensionless height (Y / H) of 20 between 0.07 and 1.21.
The height position of each part is measured. The following can be seen from the wind speed measurement results in FIG. That is, when the driver's line-of-sight height (1.35 m) or more, X =
The speed has been reduced to 0.81 or less until 4.61H. This region is not particularly important in the present invention. Below the driver's line-of-sight height, increase speed to X = 3.64H (corresponding to 12.4m of road width) (increase from 0.8)
It has a blowing effect. For this reason, the upper wing type snow protection plate 13 is
It can be seen that the effect of blowing off the road portion close to 1 is enhanced, and the lower-stage wing-shaped snow protection plate 13 has a synergistic effect with the flow passing through the lower opening of the fence, thereby maintaining the blowing-off effect farther.

In the blow-off type snow fence 11 described above, the flow along the lower surface of the downwardly protruding wing-shaped snow plate 13 is shown in FIG. 6, similarly to the flow along the upper surface of the upwardly protruding airplane wing. As described above, the wing-shaped snowboard 13 is separated from the wing-shaped snowboard 13 slightly shortly before the end of the wing-shaped snowboard 13 (point E). Therefore, it can be blown down downward by Δθ smaller than the inclination angle θ of the wing type snow protection plate 13. This is clearly shown in the flow along the lower surface of the uppermost wing-shaped snow plate 13 in FIG.
Therefore, when the blow-down angle is constant, the inclination angle θ of the wing type snow protection plate 13 can be set to be larger (closer to the horizontal), and the snow protection of the driver can be improved while improving the shielding performance and the blowing performance. The prospect of going over the fence can be improved. Also, if the inclination angle θ of the wing type snow protection plate 13 is increased (closer to the horizontal), the projected area in the wind direction decreases (the dimension a in FIG. 6 decreases).
The wind load is reduced, and there is no fear that the wing-shaped snow plate 13 will blow off. In addition, the reduction of the wind load means that the horizontal load acting on the support 12 via the wing-shaped snow protection plate 13 is reduced, and the overturning moment of the support 12 is reduced.

Further, since the wing-shaped snowboard 13 generates a lifting force P (see also FIG. 6) directed to the windward side, the wing-shaped snowboard 13 is also blown off by wind resistance at this point. Can be prevented. This lift P is exactly the same as the principle that upward lift acts on the wing of an upwardly convex airplane,
Because it is convex downward, it has a downward lift.

In the present invention, the above-mentioned actions are synergistically utilized to reduce the horizontal projection area of the wing type snow protection plate 13, and therefore, it is possible to increase the gap between the wing type snow protection plates 13. This greatly improves the driver's visibility over the snow fence. That is, as is clear from the comparison between FIG. 8 (present invention) and FIG. 9 (conventional example) which are photographs at the time of the smoke tunnel experiment, even if the inclination angle of the wing type snowproof plate 13 is set to be larger than the conventional product (horizontal) ), A sufficient blowing action can be obtained, and the visibility of the driver's line of sight can be improved, so that the wing type snow protection plate 13 is inclined at a larger inclination angle (horizontal angle than the conventional wing type snow protection plate). ), The horizontal projection area of the wing-shaped snow protection plate 13 is reduced, so that the clearance between the wing-shaped snow protection plates 13 is increased, and the driver's visibility over the snow protection fence can be greatly improved. .

As shown in FIG. 10, in order to increase the rigidity of the snow-prevention plate main body 15 ', the upper and lower edges of the snow-prevention plate main body 15' are folded back (return portions are indicated by 15'a and 15'b). It may be.

The snow plate body 15 'shown in FIG.
Are folded back portions 15'a, 15'b at the upper edge and the lower edge.
Are all cross-sectional shapes turned upward, but FIG.
As in the snow protection board body 15 "shown in FIG. 1, the folded portion 15" b at the lower edge is desirably formed to have a cross-sectional shape folded down. This is because, as shown in FIG. 10, in the folded portion 15 ′ b folded above the lower edge, snow easily piles up on the snow protection plate main body 15 ′ (easy to stay), and when the snow melts, water droplets form from the lower edge. This is because it may drip or grow as a glazing, which is not preferable.

The specific configuration of the blow-off type snow fence of the present invention is not limited to the embodiment, and various design changes can be made. For example, it is naturally possible to form a convex cross-sectional shape below the wing-shaped snow protection plate with a smooth curve. Further, in the embodiment, a plate having a constant thickness is pressed to form a downwardly protruding wing-shaped snowproof plate, but may have a cross-sectional shape in which the thickness changes like a general airplane wing. . In the embodiment, the trailing edge side of the wing type snowproof plate 13 is flat, but the trailing edge side (blowing side) may also have a downwardly convex cross-sectional shape.
In short, at least the leading edge side (blowing side) has a downwardly convex shape, and it is sufficient that the cross-sectional shape is downwardly convex as a whole. Further, the number of the wing type snowproof plates 13 is not limited to four, and can be appropriately increased or decreased. Further, the structure for attaching the wing type snowproof plate 13 to the support 12 is not limited to that of the embodiment, and may be any structure. However, if an appropriate inclination angle θ is set in consideration of various conditions such as the weather at the installation location, it is unlikely that subsequent re-adjustment is necessary. No problem. In addition, as a material of the wing type snowproof plate 13, usually, a steel plate such as a galvanized steel plate is used, but it may be made of plastic.

[0026]

According to the present invention, a plurality of wing-shaped snowboards are mounted on a support column at an interval vertically and inclined so that the blowing side becomes higher, and the cross-sectional shape of the wing-shaped snowboards is reduced. Since the shape is convex downward, the following effects can be obtained. Since the wind that has passed through the wing-shaped snow plate is blown down at an angle smaller than the inclination angle θ of the wing-shaped snow plate, the inclination angle of the wing-shaped snow plate 13 can be set larger (closer to the horizontal), This improves the driver's visibility over the snow fence, while improving the ability to block road traffic and the ability to blow off road snow. Since the inclination angle θ of the wing-shaped snowboard can be increased, the projected area in the wind direction can be reduced, whereby the wind load can be reduced and the wing-shaped snowboard can be prevented from blowing off. Since the wind load can be reduced, the horizontal load acting on the support via the wing-shaped snowboard can be reduced, and the overturning moment of the support can be reduced. In this case, it is possible to prevent the wing-shaped snowproof plate from blowing off due to wind resistance. As clarified from the results of the wind tunnel experiment, when the driver is below the driver's line of sight, the speed increases to a sufficiently distant position (increases from 0.8), so that a sweeping effect can be obtained far away. Unlike the case of the conventional upwardly convex cross-sectional shape, the phenomenon that the wind passing through the wing-shaped snowproof plate blows strongly to the road surface and does not bounce does not occur, so that it is possible to prevent the occurrence of visibility impairment for the driver. The above-described actions are synergistically utilized to reduce the horizontal projection area of the wing-shaped snow protection plate, thereby increasing the gap between the wing-shaped snow protection plates, and providing a driver's view over the snow protection fence. Can be greatly improved. By folding the upper edge and the lower edge of the wing type snowboard,
The rigidity of the wing-shaped snowboard can be improved. In this case, if the folded portion at the lower end edge is formed to have a cross-sectional shape that is folded downward as described in claim 6, snow can be easily accumulated on the snowboard body. Not preferred.

[Brief description of the drawings]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 shows a blow-off type snow fence according to one embodiment of the present invention, wherein (A) is a front view and (B) is a cross-sectional view taken along line AA of (A).

FIG. 2 is a perspective view showing a detailed structure of a blow-off type snow fence of FIG. 1;

FIG. 3 is an enlarged view of a portion B in FIG.

FIG. 4 is an enlarged view of a portion C in FIG.

FIG. 5 is a view as seen from an arrow D in FIG.

FIG. 6 is a diagram illustrating the operation of a wing-shaped snow protection plate in the blow-off type snow protection fence.

FIG. 7 is a graph showing the results of a wind tunnel test on the snow blow-off fence, and showing the relationship between the height position at each position in the width direction of the road and the wind speed (both are dimensionless).

FIG. 8 is a photograph taken during a smoke tunnel test for the snow blow-off fence.

FIG. 9 is a photograph taken during a smoke tunnel test for a conventional snow blown fence.

FIG. 10 shows another embodiment of the wing type snowproof plate, and is a view corresponding to FIG.

11 is a view showing still another embodiment of the wing type snowproof plate, in which the folded lower end edge of the wing type snowproof plate of FIG. 10 is reversed.

FIG. 12 is a view schematically showing a conventional snow blow-off fence and its operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Road 11 Blow-off snow fence 12 Prop 13 Wing type snow-prevention board 15, 15 ', 15 "Snow-prevention board main body 15'a, 15'b, 15" b Folding part 16 Side plate 16a Bracket part 17 Bolt 18 Hook part 19 Tube Shape receiving part 20 Retaining pin 25 Mounting plate 26 Connecting member

Claims (6)

[Claims] 1. A plurality of wing-shaped snow protection plates are vertically spaced between pillars which are erected at intervals along the windward side edge of a road, and are inclined so that the blowing side is higher. A blow-off type snow fence characterized by being attached and having a cross-sectional shape of the wing-shaped snow plate which is convex downward. 2. The blow-off type snow fence according to claim 1, wherein the inclination angle θ of the wing type snow prevention plate is set smaller at a higher place. 3. The wing type snow protection plate includes a hook portion bent downward on an outer surface of a side plate fixed to both ends of the snow protection plate main body, and the hook portion is fitted into a cylindrical receiving portion provided on a support column side. The blow-off type snow fence according to claim 1, wherein the blow-off type snow fence is fixed to the support post. 4. The blow-off type snow fence according to claim 3, wherein the left and right hook portions of the wing type snow plate have different sizes. 5. The blow-off type snow protection device according to claim 1, wherein the wing type snow protection plate is formed by sequentially bending a plurality of portions in a width direction of a single plate to have a downwardly convex shape. fence. 6. The blow-off type snow fence according to claim 1, wherein the wing type snow protection plate has a cross-sectional shape in which an upper edge thereof is folded upward and a lower edge thereof is folded downward.