JP2003214690A - Outside-air inlet for ventilation air conditioning facility - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent intrusion of snow to an interior as a snow protection structure in regard to an outside-air inlet for a ventilation air conditioning facility. <P>SOLUTION: An outside-air inlet duct 10 comprises a vertical part 10a and a horizontal part 10b, and air containing snow flows in from a lower inlet 11 of the vertical part 10a and it is taken in a building from an outlet 12 of the horizontal part 10b. The air 50a flows in a cambering state caused by an obliquely attached shielding plate 13 in the vertical part 10a to trap the snow. In the horizontal part 10b, the snow is removed such as 50b by meshes of a snow protection net 14a, 14b and 14c and even if it is completely clogged and blocked by the snow, the air flows in a meandering state such as 50c through alternately provided openings 15a, 15b and 15c, the snow is removed by a wall face, and rising of pressure loss is prevented. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outside air intake of a ventilation air-conditioning system, in which the outside air intake is provided with snow protection measures.

[0002]

2. Description of the Related Art FIG. 5 is a cross-sectional view showing an example of an outside air intake of a ventilation air conditioning equipment in a conventional factory, power plant, or the like.
In the figure, an outside air intake duct 80 is installed on the roof of a building 90, and outside air 91 is taken into the building. The outside air intake duct 80 has an inlet 81 and a right-angled downward outlet 82,
Partition walls 83 are attached to the inside so that the openings are alternately on the opposite side. The outside air is taken in through the inlet 81 of the outside air intake duct 80 having such a configuration, and the outside air is separated from the partition wall 8.
3, the snow which meanders and flows in and is mixed with the outside air is collided with the plurality of partition walls 83 to prevent the snow from entering the inside.

As described above, in buildings such as factories and power plants, partition walls are provided in the ducts so that the snow does not easily enter the inside of the ducts, and the suction flow velocity is reduced to reduce the snow flow. We have taken the expected measures against the sedimentation of the building and installed a large-scale outside air intake in the dry area inside the building.

[0004]

As described above, in the outside air intake of conventional factories, power plants, etc., a partition wall, etc. is structurally provided to prevent snow from entering the inside. However, if snowstorms continue several times a year, the snow will enter the duct and collide with the partition wall, etc. to prevent it from entering the duct, but the outside air intake will prevent it from entering the partition wall, etc. The generated snow is accumulated at the entrance and is blocked, or the opening formed by the partition wall in the duct is closed, and the pressure loss is increased to make it impossible to take in outside air. Therefore, there is a limit to completely preventing snow from entering only by the shape of the outside air intake, and some measure has been desired.

Therefore, in the present invention, the flow of air is meandered to prevent snow from entering without increasing the differential pressure by structurally devising the outside air intake of the ventilation and air conditioning equipment, and the net is also used to reduce the blockage due to snow. It is an object of the invention to provide an outside air intake of a ventilation air conditioning system that can completely prevent snow from entering the building as a structure.

[0006]

The present invention provides the following means (1) to (6) for solving the above-mentioned problems.

(1) An outside air intake port of a ventilation air-conditioning system that takes in outside air into a building, and has a rectangular flow path cross section consisting of a vertical portion that takes in outside air upward from below and a horizontal portion that is connected to the vertical portion. An outside air intake duct that has, a plurality of shielding plates that are alternately arranged in the vertical direction over the entire width of the opposing inner wall surfaces of the vertical portion, and each tip is attached so as to incline downward; The horizontal section is covered with a mesh member and a plurality of snow-prevention nets arranged at a predetermined interval in the flow direction are provided. An outside air intake of a ventilation air conditioning equipment, characterized in that openings are formed alternately.

(2) A rectangular flow path cross section which is an outside air intake port of a ventilation air conditioning system for taking outside air into a building and is composed of a vertical portion for taking the outside air upward from below and a horizontal portion connected to the vertical portion. An outside air intake duct that has, a plurality of shielding plates that are alternately arranged in the vertical direction over the entire width of the opposing inner wall surfaces of the vertical portion, and each tip is attached so as to incline downward; The horizontal section is covered with a mesh member and a plurality of snow-prevention nets arranged at a predetermined interval in the flow direction, and the plurality of snow-prevention nets have an opening at the center in the flow direction. An outside air intake of a ventilation air-conditioning facility, characterized in that snow protection nets and snow protection nets having openings on both left and right sides are alternately arranged.

(3) A small shielding plate which is bent at a right angle and protrudes in the flow direction is provided on the side end surface of the snow-prevention net on the side of the opening, and (1) or (2) is described. Outside air intake for ventilation and air conditioning equipment.

(4) The interval between the snow nets is 1/4 to 1/16 of the total length of the horizontal portion, and the interval between the openings is 1 / 2.5 to 1 / 7.5 of the total width of the horizontal portion. The outside air intake of the ventilation air conditioning equipment according to (1), characterized in that

(5) The interval between the snow nets is 1/4 to 1/16 of the total length of the horizontal portion, and the width of the opening in the central portion is 1 / 1.5 to 1/1 of the total width of the horizontal portion. 6, the width of the left and right openings is 1 / 2.5-1 of the total width of the horizontal portion.
/7.5, respectively, the outside air intake of the ventilation and air conditioning equipment according to (2).

(6) The width of the small shielding plate is set to 1/3 to 1/9 of the width of the opening (3)
Outside air intake of the listed ventilation air conditioning equipment.

In the first aspect of the present invention, the snow-containing air flows in from below the vertical portion, and meanders by the shielding plates provided so as to be alternately inclined. Captured by the shield. The air that has passed through the shielding plate enters the horizontal part, and the air is taken in through the mesh of the snow-prevention net in the horizontal part.However, the snow that has passed through the shielding plate is captured by the mesh of the snow-prevention net and enters the inside of the snow. Intrusion is prevented. If the snow continues to invade, the mesh of the snow-proof net will be completely closed, but it will pass while zigzag through the openings arranged alternately in a staggered manner, and further increase of the differential pressure will be limited. Further, by making the flow meander, snow adheres not only to the shielding plate and the snow-proof net but also to the entire passage wall, and the intrusion of snow can be reduced.

In the second aspect of the present invention, the snow-containing air flows in from below the vertical portion, and meanders and flows by the shielding plates that are alternately inclined. Captured by the shield. Air enters the horizontal part after passing through the blocking plate, and the air is taken in through the mesh of the snow-prevention net in the horizontal part, but the snow that passes through the blocking plate is captured by the mesh of the snow-preventing net and enters the inside of the snow. Are prevented from entering. If snow continues to invade, the mesh of the snow-proof net will be completely blocked, but the flow passing through the opening will merge at the central part, branch on both left and right sides, and meander through the merge, branch, merge point, branch point. , Most of the snow can be captured at each meandering point. Further, by making the flow meander, snow adheres not only to the shielding plate and the snow-proof net but also to the entire passage wall, and the intrusion of snow can be reduced.

According to a third aspect of the present invention, in the above-mentioned first or second aspect of the invention, when the air containing snow passes through the opening, the small shielding plate provided on the end face on the snow-prevention net side prevents the snow. As it is captured, the removal of snow can be made more reliable and further increase in differential pressure can be limited.

In (4) of the present invention, the interval between the snow nets of the above (1) invention is 1/4 to 1/16 of the total length of the horizontal portion,
The width of the opening is 1 / 2.5 to 1 / 7.5 of the total width of the horizontal part,
Each of them is set to a size that minimizes the pressure loss of the flow due to the meandering of air, and also in (5) of the present invention,
The interval of the snow net of the invention of (2) above is set to 1 of the horizontal length.
/ 4 to 1/16, the width of the opening is 1 / 1.5 to 1/6 of the total width of the horizontal part in the central part, and 1 / 2.5 to 1/7.
Further, in (6) of the present invention, the width of the small shielding plate is set to 1/3 to 1/9 of the width of the opening, respectively, so that the pressure loss due to the meandering flow of air should be minimized. You can

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 shows an outside air intake of a ventilation air conditioner according to a first embodiment of the present invention,
(A) is a side view, (b) is a top view, (c) is a perspective view of an internal snow-prevention net. 10 in (a) and (b)
Is an outside air intake duct, and the duct 10 is a vertical portion 10a.
And a horizontal portion 10b, which is a curved and rectangular flow path cross section. Numeral 11 is an inlet, which opens below the vertical portion 10a, and
2 is an exit opening to the horizontal portion 10b. In addition, exit 1
2 is not a horizontal flow outlet, but may flow vertically downward, that is, downward from the bottom surface.

Reference numeral 13 denotes a shield plate provided on the vertical portion 10a, which is alternately arranged on both wall surfaces of the vertical portion 10a and has a plate shape that is inclined and inclined downward to prevent snow from flowing in from below. It is a thing. Reference numeral 14 is a snow-prevention net which is vertically installed between the inner upper surface and the bottom surface of the horizontal portion 10b, and three snow nets 14a, 14b, 14c are arranged at a predetermined interval.

The snow-prevention net 14 is provided with an opening 15 as shown in (c), and the other entire surface is a net. As shown in (b), the opening 15a has a front stage 15a on one side. The end and the middle stage 15b are alternately arranged in a staggered manner, and the rear stage 15c is arranged alternately in a staggered manner.
The width of these openings is about 1 / of the total width as shown in (b).
About 2.5 to 1 / 7.5 (Wo = W / 2.5 to 7.5)
It is preferable that the mesh size of the net is about 1 mm to 0.8 mm to prevent snow from entering and passing through.

For reference, specific dimensions will be described with reference to an example applied to a power plant or the like. The width (W) in the figure (b) is about 15 m, and the length (L) of the horizontal portion 10b is about 25 m. Arrangement interval (P) of the snow net 14 is 3 m, openings 15a, 15
The widths (Wo) of b and 15c are about 3 m and are large enough for workers to enter inside.

In the outside air intake of the first embodiment having the above-mentioned structure, the air 50 containing snow enters the outside air intake duct 10 through the lower inlet 11 of the vertical portion 10a, and is provided in the vertical portion 10a while being alternately inclined. As shown by 50a, it flows by the closed cover plate 13, and most of it collides with the closed cover plate 13 and snow is captured.

The snow which has passed through the shielding plate 13 flows into the horizontal portion 10b, and the air containing the snow is supplied to the horizontal portion 1b as indicated by 50b.
Three snow nets 14a, 14b, 1 installed at 0b
After passing 4c, the snow is caught by the snow-preventing net, and the snow is almost prevented from entering the inside. If the snow continues to invade, the meshes of the snow nets 14a, 14b, 14c will be completely blocked, but the air will be staggered in the openings 1.
It can flow through 5a, 15b and 15c in a meandering manner as shown at 50c to limit further rise in differential pressure.
By making the flow meander like 50c, snow adheres not only to the shielding plate 13 and the snow-prevention net 14 but also to the entire passage wall of the duct 10 to prevent the snow from entering.

FIG. 2 shows an outside air intake of a ventilation air conditioning equipment according to a second embodiment of the present invention, (a) is a side view and (b) is a side view.
Is a top view and (c) is a perspective view of an internal snow net.
In the second embodiment, the structure of the snow protection net is different from that of the first embodiment, and the other structures and dimensions are the same as those of the first embodiment shown in FIG.

That is, as in FIG. 1, the outside air intake duct 1
0 consists of a vertical portion 10a and a horizontal portion 10b, and a vertical portion 1
0a has an inclined shielding plate 13, and three horizontal snow protection nets 24a, 24b, and 24c are arranged on the horizontal portion 10b. The structure is the same as that of FIG. .

The snow-prevention net 24 has an L-shape having a small shielding plate 25 at one end, and the other has an overall net structure, and is arranged so that the small shielding plate 26 side becomes an opening. That is,
As shown in (b), an opening 25a is provided on the side of the small blocking plate 26a at one end of the front stage, and an opening 26b is provided on the side of the small blocking plate 26b of the middle stage on the side opposite to the front side. The small shielding plates 26c are provided on the side opposite to the middle stage, and the openings 25c are arranged alternately.

The actual size of the second embodiment having the above-described structure is the same as that of the example shown in FIG. 1, and the width (S) of the small shielding plates 26a, 26b, 26c, which is the characteristic part of the second embodiment, has an opening. 25
About 1/3 to 1/9 of the width (Wo) of a, 25b and 25c is preferable, and 1/3 to 1/9 of 3m, that is, about 1m
It is L-shaped and has a length of about 0.33 m. In such a configuration, the air 50 containing snow enters the outside air intake duct 10 from the lower inlet 11 of the vertical portion 10a, and the vertical portion 1
50 by the shielding plate 13 that is alternately inclined to 0a.
As shown by a, most of it collides with the shielding plate 13 and snow is captured.

The snow that has passed through the shielding plate 13 flows into the horizontal portion 10b, and the air containing snow is supplied to the horizontal portion 1b as indicated by 50b.
3 snow protection nets 24a, 24b, 2 installed at 0b
After passing 4c, the snow is caught by the snow-preventing net, and the snow is almost prevented from entering the inside. When the snow continues to invade, the meshes of the snow-prevention nets 24a, 24b, 24c are completely closed, but the air is staggered in the openings 2.
It can flow meanderingly through 5a, 25b, 25c, as shown at 50c, to limit further increases in differential pressure.

Further, when passing through the openings 25a, 25b, 25c, the small shielding plates 26a, 26b, 2 at the ends of the snow-prevention nets.
6c captures the snow and prevents the intrusion of the snow contained in the meandering flow, so that the intrusion of the snow can be prevented more reliably than the structure of FIG. Further, by making the flow meander like 50c, the shielding plate 13 and the snow net 24
Not only that, snow adheres to the entire passage wall of the duct 10 to prevent snow from entering.

FIG. 3 shows an outside air intake of a ventilation air conditioning equipment according to a third embodiment of the present invention, (a) is a side view, and (b) is.
Is a top view and (c) is a perspective view of an internal snow net.
In the third embodiment of the present invention, the structure of the snow net is different from that of the first embodiment, and the other structures are the same as those of the first embodiment shown in FIG.

That is, as in FIG. 1, the outside air intake duct 1
0 consists of a vertical portion 10a and a horizontal portion 10b, and a vertical portion 1
0a has an inclined shielding plate 13, and the horizontal portion 10b is formed by arranging snow-proof nets 34 in three rows. The structure is the same as that of FIG.

As shown in (b) and (c), the snow-prevention net 34 has 34a-1, 34a-2 in the front stage and 34c- in the rear stage.
1 and 34c-2, and these front and rear stages are arranged so as to have openings 35a and 35c in the center. Moreover, these snow nets 34a-1 and 34a-
A small blocking plate 36a is provided on the central portion side of 2 with 34c-1, 34c-1.
Small shielding plates 36c are provided on c-2, respectively. In addition, the snow shield net 34b at the central portion is provided with small shielding plates 36b on both sides. Therefore, the openings are alternately arranged with the central portion 35a in the front stage, the side portions 35b in the middle stage, and the central portion 35c in the rear stage.

The dimensions of the third embodiment described above are basically the same as those shown in FIGS. 1 and 2, but the widths (W ₁ ) of the front and rear openings 35a and 35c are the outside air intake. 1 / 1.5 to 1/6 of the total width (W) of 10 is preferable, and the total width (W)
Is 15 m, W _{1 is} about 10 to 2.5 m.
The width (W ₀ ) of the openings 35b on both sides of the middle stage is preferably 1 / 2.5-1 / 7.5 of the total width (W), and is 1/2.
5 to 1 / 7.5, that is, W ₀ = 6 to 2 m.

In the outside air intake of the third embodiment having the above-mentioned structure, the air 50 containing snow enters the outside air intake duct 10 through the lower inlet 11 of the vertical portion 10a, and is provided in the vertical portion 10a while being alternately inclined. As shown by 50a, it flows by the closed cover plate 13, and most of it collides with the closed cover plate 13 and snow is captured.

The snow that has passed through the shielding plate 13 flows into the horizontal portion 10b, and the air 50b containing the snow is transferred to the snow-preventing net 34 in the preceding stage.
a-1, 34a-2, middle stage 34b, rear stage 34c-
After passing through 1,34c-2, the snow is captured by the snow-preventing net, and the invasion of the snow is almost prevented. When the snow further invades, the snow nets 34a-1, 34a-2, 34
Although the meshes of b, 34c-1 and 34c-2 completely close, the air branches from the opening 35a, flows to the openings 35b on both sides, and joins at the opening 35c, as indicated by 50c. A large amount of snow can be captured at branch points, meandering points, and confluence points.

Also, when passing through the openings 35a, 35b, 35c, a small shielding plate 36 provided at the end of the snow net.
Snow is captured by a, 36b, and 36c, and the further increase of the differential pressure can be limited. Further, by making the flow meander like 50c, the shielding plate 13, the snow net 34
Not only that, snow adheres to the entire passage wall of the duct 10 to prevent snow from entering.

FIG. 4 is a side view showing a state in which the outside air intake ports of the first to third embodiments described above are attached to the building. In the example of (a), the outlet 12 of the outside air intake duct 10 is closed, the outlet is the bottom surface 12a, and the building 60 has an opening 6 on the upper surface.
1 is provided and the outside air intake duct 10 is installed at the corner of the building 60. In this example, the air 50 is the vertical portion 10a.
Is sucked in from below and flows through the outlet 12a on the bottom surface of the right end of the horizontal portion 10b through the opening 61 of the building to the vertically lower side in the building 60.

In the example of (b), the outlet 1 of the outside air intake 10
2 is left as it is, and the opening 7 is provided in the step portion of the building 70.
1 is an example in which air is taken in from the horizontal portion 10b as it is in the horizontal direction. The outside air intake of the ventilation air conditioning equipment of the present invention may be any of the above methods (a) and (b).

[0038]

The outside air intake of the ventilation air conditioning equipment of the present invention is
(1) Outside air intake of a ventilation air-conditioning facility that takes in outside air into the building, and has a rectangular flow path cross section that consists of a vertical part that takes in outside air upward from below and a horizontal part that is connected to the vertical part The inlet duct and the entire width of the facing inner wall surface of the vertical portion, and are alternately arranged in the vertical direction,
Further, a plurality of shielding plates each of which is mounted with its tip inclined downwards, and a plurality of snow protections in which the flow passage cross section of the horizontal portion is covered with a mesh member and arranged at a predetermined interval in the flow direction. The plurality of snow-preventing nets are characterized in that openings are formed alternately on either the left or right side with respect to the flow direction.

With the above structure, the snow-containing air flows in from below the vertical portion and meanders by the shielding plates that are alternately inclined, and the snow that does not ride on the flow is blocked by the shielding plate. To be captured. Air enters the horizontal part after passing through the blocking plate, and the air is taken in through the mesh of the snow-prevention net in the horizontal part, but the snow that passes through the blocking plate is captured by the mesh of the snow-preventing net and enters the inside of the snow. Are prevented from entering. If the snow continues to invade, the mesh of the snow-proof net will be completely closed, but it will pass while zigzag through the openings arranged alternately in a staggered manner, and further increase of the differential pressure will be limited. Further, by making the flow meander, snow adheres not only to the shielding plate and the snow-proof net but also to the entire passage wall, and the intrusion of snow can be reduced.

(2) of the present invention is provided with an outside air intake duct having the same vertical and horizontal portions as in the above (1) invention, a shielding plate, and a plurality of snowproof nets. Is characterized in that snow-preventing nets having openings in the central portion and snow-preventing nets having openings in the left and right sides are alternately arranged with respect to the flow direction.

With the above construction, like the invention of (1) above, snow is captured by the vertical shielding plate and the horizontal snow-prevention net, and when the snow continues to invade, the mesh of the snow-prevention net is completely closed. However, the flow passing through the opening merges at the central part, branches at both left and right sides, and meanders by the merge and branch, and almost all snow can be captured at the merge point, the branch point, and the meander point. Further, by making the flow meander, snow adheres not only to the shielding plate and the snow-proof net but also to the entire passage wall, and the intrusion of snow can be reduced.

According to a third aspect of the present invention, in the above-mentioned first aspect or the second aspect, when the air containing snow passes through the opening, the small shielding plate provided on the end face on the side of the snow-prevention net prevents the snow. As it is captured, the removal of snow can be made more reliable and further increase in differential pressure can be limited.

In (4) of the present invention, the interval between the snow nets of the above (1) invention is 1/4 to 1/16 of the total length of the horizontal portion,
The width of the opening is 1 / 2.5 to 1 / 7.5 of the total width of the horizontal part,
Each of them is set to a size that minimizes the pressure loss of the flow due to the meandering of air, and also in (5) of the present invention,
The interval of the snow net of the invention of (2) above is set to 1 of the horizontal length.
/ 4 to 1/16, the width of the opening is 1 / 1.5 to 1/6 of the total width of the horizontal part in the central part, and 1 / 2.5 to 1/7.
Further, in (6) of the present invention, since the width of the small shielding plate is set to 1/3 to 1/9 of the opening, respectively, pressure loss due to air confluence, meandering, and branch flow is reduced. Can be minimized.

[Brief description of drawings]

FIG. 1 shows an outside air intake of a ventilation air conditioning equipment according to a first embodiment of the present invention, (a) is a side view, (b) is a top view,
(C) is a perspective view of a snow net inside.

FIG. 2 shows an outside air intake of a ventilation air conditioning equipment according to a second embodiment of the present invention, (a) is a side view, (b) is a top view,
(C) is a perspective view of a snow net inside.

FIG. 3 shows an outside air intake of a ventilation air conditioning equipment according to a third embodiment of the present invention, (a) is a side view, (b) is a top view,
(C) is a perspective view of a snow net inside.

FIG. 4 is a mounting cross-sectional view of an outside air intake of the ventilation and air conditioning equipment according to the first to third embodiments of the present invention, (a), (b).
Indicate different mounting states.

FIG. 5 is a cross-sectional view showing a mounting state of a conventional ventilation and air conditioning equipment.

[Explanation of symbols]

10 Outside air intake duct 11 entrance 12 exit 13 Shield plate 14a, 14b, 14c Snow protection net 15a, 15b, 15c openings 24a, 24b, 24c snow net 25a, 25b, 25c openings 26a, 26b, 26c Small shielding plate 34a-1, 34a-2 Snow net 34b, 34c-1, 34c-2 snow net 35a, 35b, 35c openings 36a, 36b, 36c Small shielding plate

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshiaki Yoshii             1-2 Odorihigashi, Chuo-ku, Sapporo-shi, Hokkaido             Hokkaido Electric Power Company (72) Inventor Kenji Sogabata             1-2 Odorihigashi, Chuo-ku, Sapporo-shi, Hokkaido             Hokkaido Electric Power Company (72) Inventor Shuji Noto             1-2 Odorihigashi, Chuo-ku, Sapporo-shi, Hokkaido             Hokkaido Electric Power Company (72) Inventor Shingo Matsumoto             2-1-1 Niihama, Arai-cho, Takasago, Hyogo Prefecture             Takasago Laboratory, Mitsubishi Heavy Industries, Ltd. (72) Inventor Sumio Uchida             2-1-1 Niihama, Arai-cho, Takasago, Hyogo Prefecture             Takasago Laboratory, Mitsubishi Heavy Industries, Ltd. (72) Inventor Takashi Sato             3-1-1 Wadasaki-cho, Hyogo-ku, Kobe-shi             Hishi Heavy Industries, Ltd.Kobe Shipyard F-term (reference) 3L058 BD00 BE02 BG01                 3L080 AA03 AA08 AC03 AD01

Claims (6)

[Claims] 1. An outdoor air intake of a ventilation air-conditioning facility for taking in outside air into a building, which has a rectangular flow path cross section consisting of a vertical portion for taking in outside air upward from below and a horizontal portion connected to the vertical portion. The outside air intake duct and a plurality of shielding plates, which are arranged alternately over the entire width of the facing inner wall surfaces of the vertical portion and in the vertical direction, and further each tip is attached to be inclined downward, And a plurality of snow-preventing nets arranged at a predetermined interval in the flow direction while covering the flow path cross section of the portion with a mesh member, and the plurality of snow-preventing nets alternate on either the left or right side with respect to the flow direction. An outside air intake of a ventilation air-conditioning facility, characterized in that an opening is formed in the. 2. An outdoor air intake of a ventilation air-conditioning system for taking in outside air into a building, which has a rectangular flow path cross section consisting of a vertical portion for taking in outside air upward from below and a horizontal portion connected to the vertical portion. The outside air intake duct and a plurality of shielding plates, which are arranged alternately over the entire width of the facing inner wall surfaces of the vertical portion and in the vertical direction, and further each tip is attached to be inclined downward, A plurality of snow-preventing nets arranged at predetermined intervals in the flow direction while covering the flow passage cross section of the section with a mesh member, and the plurality of snow-preventing nets have an opening in the central portion in the flow direction. An outside air intake of a ventilation air-conditioning facility, characterized in that snow-proof nets and snow-proof nets having openings on both left and right sides are alternately arranged. 3. The ventilation air-conditioning equipment according to claim 1 or 2, wherein a small shielding plate is provided at a side end surface on the opening side of the snow-preventing net, which is bent at a right angle and protrudes in a flow direction. Outside air intake. 4. The spacing of the snow-prevention net is 1/4 to 1/16 of the total length of the horizontal portion, and the spacing of the opening is 1 / 2.5-1 / 7.5 of the total width of the horizontal portion. The outside air intake of the ventilation air conditioning equipment according to claim 1, characterized in that they are respectively set. 5. The spacing of the snow nets is 1/4 to 1/16 of the total length of the horizontal portion, and the width of the opening in the central portion is 1 / 1.5 to 1/6 of the total width of the horizontal portion. In addition, the width of the openings on both the left and right sides is 1 / 2.5 to 1 / the total width of the horizontal portion.
The outside air intake of the ventilation air conditioning equipment according to claim 2, wherein each of the outside air intakes is set to 7.5. 6. The width of the small shielding plate is 1 of the width of the opening.
The outside air intake of the ventilation air conditioning equipment according to claim 3, wherein the outside air intake is set to / 3 to 1/9.