JP2022097326A - Suction device - Google Patents

Abstract

To provide a suction device that is easy to manufacture, can stably form an air curtain surrounding a wide area, and can efficiently suction the surrounded area with strong tornado flow.SOLUTION: A cylindrical blowout flow passage 30 that concentrically surrounds a suction flow passage 10 is provided; from the substantially tangential direction of the outer peripheral circle of the blowout flow passage, a blowout flow introduction passage 40 having a second fan 50 is connected to introduce a blowout flow; and the blowout flow introduced into the cylindrical blowout flow passage 30 is blown out from an annular blowout port 30a while spirally swirling around a cylindrical axis 30f. Further, guides (60, 70, 80) for expanding a blowout flow diameter may be provided.SELECTED DRAWING: Figure 1

Description

The present invention relates to a suction device for local exhaust.

Conventionally, various suction devices for local exhaust have been proposed.
For example, in the device of Patent Document 1, a propeller fan having a coaxial double structure in which wings are arranged so as to generate a blowout flow in the outer portion and a suction flow in the inner portion is used, and a blowout flow is generated in the outer portion. While forming an air curtain, the inner part sucks the air inside. By rotating the propeller fan, the blowout flow and the suction flow are rotated in the same direction to generate a tornado flow, and effective suction is performed.
In the apparatus of Patent Document 2, two sirocco fans are used, and one fan blows air from the peripheral portion to generate an air curtain, and the other fan sucks air from the central portion. At this time, an inclined blade is provided in the middle of the passage of the blowout flow to swirl the blowout flow, thereby stably forming an air curtain and generating a tornado flow.

Japanese Unexamined Patent Publication No. 5-6008 Japanese Unexamined Patent Publication No. 8-75208

However, in the suction device described in Patent Document 1, since the swirl of the blowout flow is generated only by the rotation of the propeller fan that generates the blowout flow, the swirl of the blowout flow may not always be sufficient. In particular, if the blowout flow is expanded in a skirt shape by a guide in order to form an air curtain that encloses a wide area, there is a concern that the turning will be weakened and the air curtain will become unstable. Further, as a result, there is a concern that the tornado flow of the suction flow formed by reversing the air curtain is also weakened.

In the suction device described in Patent Document 2, since the blown airflow is generated by the sirocco fan, the airflow has a small swirl in the first place, and there is a concern that it cannot be swirled sufficiently only by the inclined blades. As a result, as in Patent Document 1, there is a concern that an air curtain or a tornado flow cannot be stably formed. Another problem is that it is not always easy to manufacture a blowout passage having inclined blades.

The present invention has been made in view of the above circumstances, and is easy to manufacture, can stably form an air curtain that encloses a wide area, and can efficiently suck the enclosed area with a strong tornado flow. The purpose is to provide the device.

The suction device of the present invention is a suction device for performing local exhaust, and is a suction device.
With a suction flow passage that has a substantially circular suction port and allows the suction flow to flow,
A first fan arranged in the suction flow passage and generating the suction flow,
A cylindrical outlet passage that has a substantially annular outlet that surrounds the suction port at one end and is closed at the other end, and that coaxially surrounds the vicinity of the suction port of the suction flow passage.
It is connected to and communicates with the outer periphery of the other end side of the cylindrical outlet passage from the substantially tangential direction of the outer peripheral circle of the cylindrical outlet passage, and the outlet is flowed around the cylindrical axis in the cylindrical outlet passage. The blowout flow introduction passage that is introduced so as to turn around, and
A second fan provided in the blowout flow introduction passage and generating the blowout flow, and
It is characterized by having.
With this configuration, the blowout flow introduced into the cylindrical blowout flow path is blown out from the outlet while spirally swirling around the cylindrical axis, so that a swirling air curtain can be realized. As a result, it is possible to realize a suction device that is easy to manufacture, can stably form an air curtain that encloses a wide area, and can efficiently suck the enclosed area with a strong tornado flow.

The suction device is continuously arranged on the inner circumference of the substantially annular outlet, and has a rotationally symmetric intermediate guide that expands the outlet.
A substantially rotationally symmetric outer guide, which is continuously arranged on the outer periphery of the substantially annular outlet and forms an outlet diameter expanding passage of the outlet flow between the intermediate guide and the intermediate guide.
An inner guide having a cylindrical shape or a substantially rotating object having a smaller spread than the intermediate guide, which is continuously provided on the outer periphery of the suction port and forms an upstream passage of the suction flow inside.
It is preferable to have more.
The above-mentioned "substantially rotating target shape" includes, for example, a substantially skirt shape, a shape composed of a cylindrical portion and a disk-shaped portion, a hemispherical shape, or a shape obtained by combining these.
With this configuration, the air curtain formed by the blowout stream is further expanded to surround a wide area, and the outlet and the suction port are spatially separated from each other, so that the blowout stream can be prevented from being immediately turned back and sucked. can.

The first fan may be a propeller fan, which rotates in the same direction as the swirling direction of the blowout stream in the cylindrical blowout flow path.
With this configuration, the swirling direction of the suction flow formed by reversing the air curtain and the rotation direction of the first fan that generates the suction flow are the same, so that the tornado flow can be easily formed.

The suction device has a plurality of the outlet flow introduction passages connected to the outer periphery of the other end side of the cylindrical outlet passage, and the second fan provided in each of the outlet flow introduction passages. Then, the blowout flow may be introduced from each of the blowout flow introduction passages into the cylindrical blowout flow passage so as to swirl in the same direction around the cylindrical axis.
With this configuration, the swirl of the outlet in the cylindrical outlet passage can be further strengthened and made uniform, whereby a more stable air curtain can be formed and efficient suction can be realized over a wide area.

The suction device includes an inner cylindrical portion extending downward from the inner circumference of the substantially annular outlet.
A lower annular disk whose inner circumference is fitted to the outer circumference of the inner cylindrical portion and is provided horizontally,
An upper annular disk provided parallel to the lower annular disk and having a diameter larger than that of the lower annular disk so as to extend outward from the outer circumference of the substantially annular outlet.
An outer tubular portion extending downward from the outer periphery of the upper annular disk and having an inner peripheral side forming an annular gap with the outer periphery of the lower annular disk.
A plurality of spirally arranged partition plates are included in the disk-shaped space between the lower annular disk and the upper annular disk.
The blowout flow is configured to be introduced from the substantially annular outlet, pass between the plurality of partition plates in the disk-shaped space, and swirl, and then blown out from the annular gap. It may be one that further has a disk passage.
With this configuration, it is possible to increase the diameter of the air curtain while stably maintaining the swirling of the blowout flow formed in the cylindrical blowout flow passage with a structure that is easy to manufacture.

According to the suction device according to the present invention, a cylindrical blowout flow path that concentrically surrounds the suction flow path is provided, and a blowout flow introduction passage having a second fan is connected from the substantially tangential direction of the outer peripheral circle thereof to blow out. Since the flow is introduced, the blowout flow introduced into the cylindrical blowout flow path is blown out from the annular outlet while swirling in a spiral shape. As a result, it is possible to realize a suction device that is easy to manufacture, can stably form an air curtain that encloses a wide area, and can efficiently suck the enclosed area with a strong tornado flow.

It is a vertical sectional view conceptually showing the 1st Embodiment of the suction device which concerns on this invention. FIG. 3 is a sectional view taken along the line AA of the suction device of FIG. It is a bottom view of the suction device of FIG. It is a vertical sectional view conceptually showing the 2nd Embodiment of the suction device which concerns on this invention. 4 is a cross-sectional view taken along the line AA of the suction device of FIG. It is a vertical sectional view conceptually showing the 2nd Embodiment of the suction device which concerns on this invention. It is an example of the BB sectional view of the suction device of FIG. It is another example of the BB sectional view of the suction device of FIG. It is sectional drawing which shows the application example of the suction device of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First Embodiment)
FIG. 1 is a cross-sectional view showing a first embodiment of the suction device according to the present invention. This suction device 1 is a suction device that performs so-called local exhaust, and includes a suction flow passage 10, a first fan 20, a cylindrical outlet flow passage 30, an outlet flow introduction passage 40, and a second fan 50. Further, an intermediate guide 60, an outer guide 70, and an inner guide 80 provided continuously on the suction target side in these passages are included.

The suction flow passage 10 has a substantially circular suction port 10a and is a passage through which the suction flow flows. In the present embodiment, the suction flow passage 10 is formed by a duct (also referred to as an inner pipe 10b).

The first fan 20 is arranged in the suction flow passage 10 to generate a suction flow. The first fan 20 is a so-called axial flow type propeller fan in which a blade 20a is rotated by a driving means 20b such as a motor to generate a suction flow. In this configuration, if the rotation direction of the first fan 20 is set to the same direction as the turning direction of the blowout flow, which will be described later, there is an effect that the suction flow is slightly easily turned into a tornado flow. However, the first fan 20 may be any fan as long as it can blow air, and may be, for example, a sirocco fan.

The cylindrical outlet passage 30 has a substantially annular outlet 30a surrounding the suction port 10a at one end and the other end (30c) is closed, so that the suction flow passage 10 is near the suction port 10a. It is a passage that surrounds the area coaxially. In the present embodiment, the cylindrical outlet flow passage 30 is formed between the outer pipe 30b and the outer pipe 30b which is a duct surrounding the inner pipe 10b, and the other end side is closed by the closing plate 30c.

The blowout flow introduction passage 40 is connected to the outer peripheral surface 30d on the other end side of the cylindrical blowout flow path 30 from the substantially tangential direction of the outer peripheral circle 30e and communicates with the cylindrical blowout flow path 30. In the present embodiment, the blowout flow introduction passage 40 is formed of a blowout flow introduction pipe 40a made of a duct having a rectangular cross section welded to the outer periphery of the outer pipe 30b. In the cross-sectional view of FIG. 2, the upper side surface of the blowout flow introduction passage 40 is formed so as to be substantially tangent to the outer peripheral circle 30e of the cylindrical blowout flow passage 30 (outer pipe 30b), and the blowout flow introduction passage 40 is formed. The horizontal width of the above is substantially the same as the width of the cylindrical outlet passage 30 (that is, the distance between the outer peripheral surface of the inner pipe 10b and the inner peripheral surface of the outer pipe 30b). As a result, the blowout flow introduced from the blowout flow introduction passage 40 into the cylindrical outlet flow passage 30 spirally swirls in the cylindrical outlet flow passage 30 around the cylindrical shaft 30f.

The present invention is not limited to the above configuration, and the blowout flow introduction passage 40 may have a circular cross section, and in FIG. 2, the horizontal width of the blowout flow introduction passage 40 is the width of the cylindrical blowout flow passage 30. It may be different. Further, the direction of the blowout flow introduction passage 40 may be slightly deviated from the horizontal direction in FIGS. 1 and 2 as long as a swirling flow can be efficiently generated.
Further, the length of the blowout flow introduction passage 40 is sufficient as long as it can direct the blowout flow in the substantially tangential direction of the outer peripheral circle 30e under the action of the second fan 50.

The second fan 50 is provided in the blowout flow introduction passage and generates the blowout flow. In the present embodiment, the second fan 50 is a so-called axial flow type propeller fan like the first fan 20, and the blades 50a are rotated by a drive means 50b such as a motor in the blowout flow introduction passage 40. To generate a blowout stream. However, the second fan 50 may be any fan as long as it can blow air, and may be, for example, a sirocco fan.

As shown in FIG. 1, the intermediate guide 60 is a substantially rotational target type guide that is continuously arranged on the inner circumference of the substantially annular outlet 30a and expands the outlet flow. In the present embodiment, the intermediate guide 60 is formed in a substantially skirt shape.

The outer guide 70 is a substantially rotational target type guide continuously arranged on the outer periphery of the substantially annular outlet 30a, and forms the outlet diameter expanding passage 65 of the outlet flow with the intermediate guide 60. is doing. The outer guide 70 is also formed in a substantially skirt shape in the present embodiment.

Further, the inner guide 80 is continuously provided on the outer periphery of the suction port, has a cylindrical shape or a substantially rotationally symmetric shape having a smaller spread than the intermediate guide, and forms an upstream passage of the suction flow inside. The inner guide 80 is formed in a substantially cylindrical shape in the present embodiment.
The intermediate guide 60 and the inner guide 80 do not necessarily have to be independent members, and may be integrally formed with the inner pipe 10b. Further, the outer guide 70 does not necessarily have to be an independent member, and may be integrally formed with the outer pipe 30b.
Further, as described above, the intermediate guide 60, the inner guide 80, and the outer tube 30b are not limited to a substantially skirt shape or a tubular shape, and may be a substantially rotationally symmetric shape, for example, from a tubular portion and a disk-shaped portion. The shape may be a hemispherical shape, a hemispherical shape, or a combination thereof.

Next, the operation of the suction device 1 of the present embodiment configured as described above will be described with reference to FIGS. 1 to 3.
When the first fan 20 and the second fan 50 are rotationally driven, air is introduced into the cylindrical outlet passage 30 through the outlet introduction passage 40 by the second fan 50. At this time, since the outlet flow introduction passage 40 is connected from the substantially tangential direction of the outer peripheral circle 30e of the cylindrical outlet flow passage 30, the introduced outlet flow is around the cylindrical shaft 30f in the cylindrical outlet flow passage 30. It becomes a blowout stream that swirls in a spiral. Since the other end side of the cylindrical outlet passage 30 is blocked by the closing plate 30c, this outlet is swirling and the outlet diameter is expanded from the outlet 30a to the intermediate guide 60 and the outer guide 70. It flows into 65 and is blown out in a skirt shape from the outlet 65a to form a swirling air curtain AC (see FIG. 1).

In the present embodiment, a spatial gap G is provided between the blowout flow and the suction flow by the inner guide 80 and the intermediate guide 60, and the gap G causes the outlet 65a of the blowout diameter expansion passage 65 to exit. It is prevented that a part of the blown stream is immediately reversed and sucked into the suction port 80a of the inner guide 80. Therefore, an air curtain AC that surrounds a wide area is formed.

On the other hand, a suction flow is generated by the rotation of the first fan 20, and the air inside the air curtain AC is sucked through the inner guide 80 and the inner pipe 10b. Therefore, the blowout flow forming the air curtain AC is turned back when it reaches the reaching point determined by the wind speed, turns to the suction port 80a side of the inner guide 80, and turns as it is while turning the suction port 80a of the inner guide 80. Ascend towards. At this time, the blowout flow is folded back, so that the radius of turning is reduced while the rotational kinetic energy is maintained, so that the turning speed becomes high and a tornado-shaped vortex reaching the suction target 90 is formed. The tornado-shaped vortex can efficiently suck the suction target 90 (for example, steam or smoke generated from the cooking range table 91).

As shown in FIG. 1, the suction target 90 such as the sucked gas passes through the inside of the inner pipe 10b forming the suction flow passage 4 as a suction flow, and is exhausted to the outside from the discharge port 10c.

FIG. 3 is a view of the main part of the suction device 1 shown in FIG. 1 as viewed from the bottom surface side, and shows how the blowout flow transitions to the suction flow. In the figure, the blowout flow swirled in the blowout diameter expansion passage 65 is blown out from the blowout port 65a, and when it reaches the reaching point, it folds back toward the inner guide 80 side to form a tornado-shaped suction flow. It is conceptually shown that the suction target 90 in the local region together with the flow is sucked into the suction port 80a of the inner guide 80. In the present embodiment, as shown in FIG. 3, both the blowout flow and the suction flow are rotated clockwise when viewed from the bottom surface side, but the present invention is not limited to this, and the flow is rotated counterclockwise. You may.

According to the suction device 1 of the present embodiment, a cylindrical outlet flow passage 30 surrounding the suction flow passage 10 is provided, and an outlet flow introduction passage 40 having a second fan 50 is connected from the substantially tangential direction of the outer peripheral circle 30e. Therefore, the blowout flow introduced into the cylindrical blowout flow path 30 is blown out from the annular outlet 30a while spirally swirling around the cylindrical shaft 30f. As a result, it is possible to realize a suction device that is easy to manufacture, can stably form an air curtain AC that encloses a wide area, and can efficiently suck the enclosed area with a strong tornado flow.

Further, in the present embodiment, since the first fan 20 that generates the suction flow and the second fan 50 that generates the blowout flow are separately controlled, the output balance of the two fans can be adjusted. , It is possible to optimally set the flow rates of the suction flow and the blowout flow, which enables the optimum suction according to the usage environment.

The intermediate guide 60, the outer guide 70, and the inner guide 80 are not essential elements for the suction device of the present invention, and may not be provided depending on the application. Further, depending on the application, various guides such as a guide for reducing the flow path diameter of the blowout flow or the suction flow may be provided. However, by providing the intermediate guide 60, the outer guide 70, and the inner guide 80, the air curtain AC formed by the blowout flow is expanded to surround a wider range, and the outlet 65a and the suction port 80a are spatially separated. Therefore, it is preferable because it is possible to prevent the blowout stream from being immediately turned back and sucked.

(Second embodiment)
FIG. 4 is a vertical sectional view conceptually showing the suction device 101 of the second embodiment of the present invention, and FIG. 5 is a sectional view taken along the line AA of the suction device 101 of FIG. In the present embodiment, in the suction device 1 of the first embodiment, the blowout flow introduction passage 40 and the second fan 50 are provided at two opposite positions of the cylindrical blowout flow passage 30.
Since the other configurations are the same as those of the first embodiment, duplicated description will be omitted.
With such a configuration, the swirl of the blowout flow in the cylindrical blowout flow path 30 can be further strengthened and made uniform, thereby forming a more stable air curtain AC and efficiently surrounding a wide area. Aspiration can be achieved.
In this example, the blowout flow introduction passage 40 and the second fan 50 are provided at two locations facing each other in the cylindrical blowout flow passage 30, but may be provided at three or more locations.

(Third embodiment)
FIG. 6 is a vertical sectional view conceptually showing the suction device 201 of the third embodiment of the present invention, and FIGS. 7 and 8 are examples of BB sectional views of the suction device 201 of FIG. .. In the present embodiment, in the suction device 1 of the first embodiment, instead of providing the intermediate guide 60, the outer guide 70, and the inner guide 80, the blowout flow is further swirled to the substantially annular outlet 30a. It is a form in which a swivel disk passage 210 is provided. Since the other configurations are the same as those of the first embodiment, duplicated description will be omitted.

The blowout flow swirling disk passage 210 connects an inner tubular portion 211, a lower annular disk 212, an upper annular disk 213, an outer tubular portion 214, and a plurality of partition plates 217. Is formed by.
The inner cylindrical portion 211 is a member extending downward from the inner circumference of the air outlet 30a. The inner circumference of the lower annular disc 212 is fitted to the outer circumference of the inner tubular portion 211, whereby the lower annular disc 212 is horizontally provided. On the other hand, an upper annular disk 213 having a diameter larger than that of the lower annular disk 212 is provided parallel to the lower annular disk 212 so as to extend outward from the outer periphery of the outlet 30a. An outer cylindrical portion 214 is extended downward on the outer periphery of the upper annular disk 213, and an annular gap 215 is formed between the inner peripheral side thereof and the outer periphery of the lower annular disk 212. Has been done.
Further, a plurality of partition plates 217 are spirally arranged in the disc-shaped space 216 formed between the lower annular disc 212 and the upper annular disc 213. These members may be connected to each other by welding, screwing, or the like, or may be integrally formed.

In the suction device 201 of the present embodiment having such a blowout flow swirling disk passage 210, the swirling blowout flow formed by the cylindrical blowout flow passage 30 is a blowout flow swirling circle from a substantially annular outlet 30a. It is introduced into the plate passage 210 and expands the disk-shaped space 216 toward the periphery. At this time, since the blowout flow is further swirled when passing between the plurality of partition plates 217, the swivel speed does not decrease so much even if it spreads, and it is configured to blow out from the annular gap 215. .. Other operations are the same as those of the suction device 1 of the first embodiment.
With this configuration, it is possible to increase the diameter of the air curtain while stably maintaining the swirling of the blowout flow formed in the cylindrical blowout flow passage with a structure that is easy to manufacture.
The partition plate 217 may be any as long as it can swirl the blowout flow, and may be, for example, a plate-shaped one having a constant width shown in FIG. 7 or a triangular one shown in FIG. 8 in a cross-sectional view. In the cross-sectional view of FIG. 8, the triangular partition plate 217 suppresses an increase in the cross-sectional area of the flow path even if the blowout flow spreads to the peripheral portion of the disk-shaped space 216, and thus has an effect of suppressing a decrease in the blowout speed. it is conceivable that.

(Application example)
FIG. 9 is a diagram conceptually showing an application example of the suction device 1 according to the first embodiment of the present invention. In this example, the steam and smoke generated from the cooking range table 91 installed indoors are set as the suction target 90, and after being sucked by the suction device 1, a point away from the main body of the suction device 1, for example, to the inner pipe 10b to the outside. Exhaust through the connected exhaust duct 10d. On the other hand, the blowout stream is taken from indoors. In FIG. 1, 92 shows a mounting table for a cooking range table 91, and 93 shows an outer wall of a building.

In the suction device 1 shown in FIG. 9, a first fan 20 for generating a suction flow is connected to a downstream position in the suction flow passage 10, that is, an inner pipe 10b, as compared with the suction device 1 in FIG. It is arranged in the exhaust duct 10d, and the spatial gap G between the intermediate guide 60 and the inner guide 80 is further increased to expand the enclosing range of the air curtain AC, but the basic configuration is the same. Is.
The operation of the suction device 1 is as described above. That is, when the first fan 20 and the second fan 50 are rotationally driven, the indoor air is introduced through the blowout flow introduction passage 40 by the second fan 50. The introduced air becomes an outlet that spirally swirls in the cylindrical outlet passage 30, and passes through the outlet diameter expansion passage 65 between the intermediate guide 60 and the outer guide 70 from the outlet 30a while swirling. A skirt-like blown air curtain AC is formed from the air outlet 65a to form a swirling air curtain AC.

Since the blowout flow forming the air curtain AC surrounds the suction target 90 (steam, smoke, etc. generated from the cooking range table 91) to form a tornado flow, the suction target 90 should be efficiently sucked. Can be done.

As shown in FIG. 1, the suction target 90 such as the sucked gas passes through the inside of the inner pipe 10b and the exhaust duct 10d forming the suction flow passage 10 as the suction flow, and is exhausted to the outside from the discharge port 10c. ..

The suction devices 101 and 201 of the second and third embodiments can be similarly applied to the applications of this example.
Since the suction devices 1, 101 and 201 separately provide a first fan 20 for generating a suction flow and a second fan 50 for generating a blowout flow, the flow rates of the suction flow and the blowout flow are optimized. It is possible to set to, which enables optimum suction according to the usage environment.

The suction devices 1, 101 and 201 are used not only for cooking microwave ovens, but also for exhausting smoke generated from roasted meat table stoves, etc., and for sucking locally generated foul odors and dust and discharging them to the outside. Can be applied.

1: Suction device 10: Suction flow passage 10a: Suction port 10b: Inner pipe 10c: Discharge port 10d: Exhaust duct 20: First fan 20a: Blade 20b: Drive means 30: Cylindrical outlet flow passage 30a: Outlet 30b: Outer pipe 30c: Closing plate 30d: Outer circumference 30e: Outer circumference circle 30f: Cylindrical shaft 40: Blowout flow introduction passage 40a: Blowout flow introduction pipe 50: Second fan 50a: Blade 50b: Drive means 65: Blowout diameter expansion passage 65a: Outlet 60 (in the outlet diameter expansion passage): Intermediate guide 70: Outer guide 80: Inner guide 80a: Suction port 90 (inner guide): Suction target 91: Cooking range stand 92: Mounting stand 93: Building Outer wall 101: Suction device 201 (in the second embodiment): Suction device 210 (in the third embodiment): Blow-out flow swirling disk passage 211: Inner cylindrical portion 212: Lower annular disk 213: Upper annular Disk 214: Outer cylindrical part 215: Circular gap 216: Disk-shaped space 217: Partition plate AC: Air curtain G: Gap

Claims (5)

A suction device for local exhaust
With a suction flow passage that has a substantially circular suction port and allows the suction flow to flow,
A first fan arranged in the suction flow passage and generating the suction flow,
A cylindrical outlet passage that has a substantially annular outlet that surrounds the suction port at one end and is closed at the other end, and that coaxially surrounds the vicinity of the suction port of the suction flow passage.
It is connected to and communicates with the outer periphery of the other end side of the cylindrical outlet passage from the substantially tangential direction of the outer peripheral circle of the cylindrical outlet passage, and the outlet is flowed around the cylindrical axis in the cylindrical outlet passage. The blowout flow introduction passage that is introduced so as to turn around, and
A second fan provided in the blowout flow introduction passage and generating the blowout flow, and
Has a suction device. A substantially rotationally symmetric intermediate guide that is continuously arranged on the inner circumference of the substantially annular outlet and expands the outlet,
A substantially rotationally symmetric outer guide, which is continuously arranged on the outer periphery of the substantially annular outlet and forms an outlet diameter expanding passage of the outlet flow between the intermediate guide and the intermediate guide.
A cylindrical or substantially rotationally symmetric inner guide that is continuously provided on the outer periphery of the suction port and forms an upstream passage of the suction flow on the inner side, and has a smaller spread than the intermediate guide.
The suction device according to claim 1, further comprising. The suction device according to claim 1, wherein the first fan is a propeller fan, which rotates in the same direction as the swirling direction of the blowout stream in the cylindrical blowout flow path. Each of the outlets has a plurality of the outlet flow introduction passages connected to the outer periphery of the other end side of the cylindrical outlet passage, and the second fan provided in each of the outlet flow introduction passages. The suction device according to claim 1, wherein the suction device is introduced from the flow introduction passage into the cylindrical blowout passage so as to swirl the blowout flow around the cylindrical axis in the same direction. An inner cylindrical portion extending downward from the inner circumference of the substantially annular outlet, and
A lower annular disk whose inner circumference is fitted to the outer circumference of the inner cylindrical portion and is provided horizontally,
An upper annular disk provided in parallel with the lower annular disk and having a diameter larger than that of the lower annular disk so as to extend outward from the outer circumference of the substantially annular outlet.
An outer tubular portion extending downward from the outer periphery of the upper annular disk and having an inner peripheral side forming an annular gap with the outer periphery of the lower annular disk.
A plurality of spirally arranged partition plates are included in the disk-shaped space between the lower annular disk and the upper annular disk.
The blowout flow is configured to be introduced from the substantially annular outlet, passed between the plurality of partition plates in the disk-shaped space, and swivel, and then blown out from the annular gap. The suction device according to claim 1, further comprising a disk passage.

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