JP3495351B2 - Damper - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is, for example, attached to a duct used in a natural ventilation system for ventilating indoors and outdoors using wind or the like, for adjusting the amount of air passing through the duct. Regarding dampers.

[0002]

2. Description of the Related Art Conventionally, as a damper that is attached to a duct used in a so-called natural ventilation system and adjusts the amount of air passing through the duct, the air flow in the duct passes through the duct in the forward direction. Backflow prevention with an airflow adjustment damper that has an airflow adjustment function that adjusts the airflow within a predetermined range, and a backflow prevention function that reduces the airflow passing through the duct to almost zero when the airflow in the duct is in the opposite direction. The damper is known. By adjusting the amount of air passing through the duct using the air flow rate adjustment damper and the backflow prevention damper, it is possible to perform indoor and outdoor ventilation by a natural ventilation system using wind or the like.

The damper described in Japanese Patent Laid-Open No. 2000-274797 is also one of the dampers used in the above-mentioned natural ventilation system, and, for example, as shown in FIG. A main blade 3 rotatable about a frame member 102 forming a part of b and a main blade rotating shaft 104 orthogonal to the axial direction of the duct b.
Then, the damper 101 is formed from the auxiliary blade 105 and the like which are rotatable around the auxiliary blade rotation shaft 106 which substantially coincides with the main blade rotation shaft 104.

In the damper 101, when there is no wind, as shown in FIG. 11, the main blade 103 is positioned by its own weight and the stopper 110 so as to be along the axis of the duct b and divide the inside of the duct b into two. In addition, the auxiliary blade 105 is positioned so as to be orthogonal to the axis of the duct b due to its own weight. And
During normal wind, as shown in FIGS. 12 to 15, the auxiliary blade 1
05 rotates in a direction to increase the amount of air passing through the duct b, and as the wind pressure increases, the main blades 103 receive a lifting force to reduce the amount of air passing through the duct b. By rotating in the direction, the air volume passing through the duct b is adjusted within a predetermined range. Further, at the time of headwind, as shown in FIGS. 16 and 17, the auxiliary vanes 105 and the duct b receiving the wind pressure.
Main blade 1 that rotates in a direction that reduces the amount of air passing through it
In cooperation with 03, the backflow is prevented by making the air volume passing through the duct b almost zero.

That is, since the damper 101 can adjust the amount of air passing through the duct b within a predetermined range regardless of the amount of air flowing into the duct b, it can be used for a natural ventilation system using wind or the like. is there. Also, damper 1
01 has an integrated air flow adjustment damper and backflow prevention damper, and has a relatively simple structure, which reduces manufacturing costs, requires a small installation space, and can be installed freely. The degree is increasing.

[0006]

By the way, in the natural ventilation system, even when the amount of air flowing into the duct b is relatively small during normal wind, the small amount of air is efficiently utilized for ventilation. Is desired. Here, in the damper 101, in the normal wind, the auxiliary blades 105 are pushed up as the amount of air flowing into the duct b increases, and the passage area of the air flow in the duct b increases.
Therefore, the wind velocity decreases and the pressure loss coefficient decreases, which reduces the pressure loss. Therefore, when the amount of air flowing into the duct b during normal wind is relatively small, the auxiliary vane 105 is not pushed up, so that the passage area of the air flow in the duct b becomes small, and therefore the wind speed does not drop. As a result, the pressure loss coefficient becomes large, which increases the pressure loss and deteriorates the ventilation efficiency.

Further, the damper 101, when the amount of air flowing into the duct b during normal wind is relatively large,
The lift force causes the main blade 103 to rotate so that the amount of air passing through the duct b is reduced. Here, the lift force is generated when the main blade 103 is at a position rotated by a predetermined angle with respect to the axis of the duct b, which further assists the rotation of the main blade 103. It is a thing. However, the damper 101
As described above, the main blades 103 are located along the axis of the duct b when there is no wind. Therefore,
The amount of air flowing into the duct b increases and the auxiliary blade 105
The force for rotating the main blade 103 does not act until the blade is pushed up and comes into contact with the wind receiving portion 107 formed on the lower surface of the main blade 103. That is, the main blade 103 does not rotate until the air volume increases to some extent. The poor sensitivity of the rotation of the main blades 103, that is, the sensitivity of adjusting the amount of air passing through the duct b is caused by the damper 101.
Considering that is repeatedly used for a long period of time, the effect on ventilation performance is large.

Therefore, it is an object of the present invention to improve the ventilation efficiency by reducing the pressure loss in the duct even when the amount of air flowing into the duct is relatively small. An object of the present invention is to provide a damper capable of improving ventilation performance by improving the adjustment sensitivity of the amount of air passing through.

[0009]

In order to solve the above problems, the invention according to claim 1 is a damper (pressure loss reducing damper 1) which is attached to a duct a and which adjusts the amount of air passing through the duct a. A frame member 2 forming a part of the duct a by being connected to the duct a, and a main blade 3 rotatable about a main blade rotation shaft 4 orthogonal to the axial direction of the duct a. An auxiliary vane 5 rotatable about an auxiliary vane pivot shaft 6 that substantially coincides with the main vane pivot shaft 4; and the auxiliary vane 5 provided on the auxiliary vane 5 and receiving wind pressure during normal wind.
Is provided so as to rotate in a direction in which the amount of air passing through the duct a is increased. The main blade 3 is rotated in a direction to increase the amount of air passing through the inside of the duct a, and as the amount of air flowing into the duct a is increased, the main blade 3 receives a lifting force to increase the amount of air passing through the duct a. By rotating in the decreasing direction, the amount of air passing through the duct a is adjusted within a predetermined range, and at the time of a backwind, the amount of air passing through the duct a due to the auxiliary blade 5 and wind pressure is reduced. It is characterized in that the backflow is prevented by making the amount of air passing through the inside of the duct a substantially zero by cooperating with the main blades 3 which rotate in the direction.

According to the first aspect of the present invention, the damper rotates in a direction in which the wind receiving portion receives wind pressure and the auxiliary vanes increase the amount of air passing through the duct during normal wind. Along with the increase in the amount of air flowing into the duct, the main blade receives a lifting force and rotates in a direction in which the main blade reduces the amount of air passing through the duct, so that the amount of air passing through the duct falls within a predetermined range. Adjust within. Further, when the wind is back, the damper cooperates with the auxiliary blades and the main blades that rotate in a direction of receiving the wind pressure to reduce the amount of air passing through the duct, thereby reducing the amount of air passing through the duct. Set to zero to prevent backflow.

That is, the damper can adjust the amount of air passing through the duct within a predetermined range, and can prevent backwind in the duct.
At this time, when the amount of air flowing into the duct at the time of normal wind is relatively small, the wind receiving portion rotates in a direction in which the auxiliary blade receives the wind pressure and increases the amount of air passing through the duct. Acts like. Therefore, even when the amount of air flowing into the duct during normal wind is relatively small,
The passage area of the airflow in the duct is large, and therefore
Wind speed decreases. This reduces the pressure loss coefficient and reduces the pressure loss in the duct. Therefore, even when the amount of air flowing into the duct is small, it is possible to improve the ventilation efficiency by efficiently using this amount of air.

According to the first aspect of the present invention, the damper is integrated with the air flow rate adjusting damper and the backflow preventing damper, and has a relatively simple structure. Therefore, the manufacturing cost is suppressed. It is possible.

Further, according to the first aspect of the present invention, the damper has the air flow rate adjusting damper and the backflow preventing damper integrated with each other, so that the installation space is small, and therefore the degree of freedom of the installation position is increased. It is possible.

The duct may have a cylindrical shape, an elliptic cylindrical shape, a rectangular cylindrical shape, or the like. Therefore, the shapes of the frame member, the main blade, and the auxiliary blade may be appropriately changed and designed according to the shape of the duct. The position of the main blade rotating shaft may be a position passing through the center of the duct, but may be a position offset from the center of the duct. Furthermore, the position of the auxiliary blade changes corresponding to the position of the main blade rotating shaft.

The main blade has a size and shape corresponding to the inner cross-section of the duct formed by a plane orthogonal to the axis of the duct (specifically, when the duct has a cylindrical shape, an outer diameter corresponding to the inner diameter of the duct). And the like). The main blade is rotatable within the duct about the main blade rotating shaft, and is capable of closing the internal space of the duct above the plane including the main blade rotating shaft and the axis of the duct, and Other materials may be used as long as they can close the internal space below the plane.

The auxiliary vanes have, for example, a size and shape corresponding to a portion below the auxiliary vane rotation axis in the inner hollow cross section of the duct formed by a plane orthogonal to the duct axis (specifically, when the duct has a cylindrical shape. Is a disk divided into two parts having an outer diameter corresponding to the inner diameter of the duct). Other auxiliary blades may be used as long as they can rotate in the duct about the auxiliary blade rotation axis and can close the internal space below the plane.

The invention according to claim 2 is, for example, as shown in FIGS.
In the damper (pressure loss reduction damper 1) according to claim 1, the main blades 3 are
It is characterized in that it is held at a position rotated by a predetermined angle in a direction that reduces the amount of air passing through the duct a during normal wind.

According to the second aspect of the present invention, the main blade is held at a position rotated by a predetermined angle in a direction that reduces the amount of air passing through the duct during normal wind when there is no wind. Here, as described above, the lift force generated in the main blade is such that the passage area of the air flow in the duct on the leeward side of the main blade rotation axis is greater than the passage area of the air flow in the duct on the windward side. Is also caused by becoming smaller. That is, it is generated when the main blade is rotated by a predetermined angle in a direction that reduces the amount of air passing through the duct during normal wind. By the way, since the main blades are held at the position when there is no wind, the main blades can be rotated by receiving lift even when the air volume is relatively small during normal wind. Therefore, the ventilation performance can be improved by improving the rotational sensitivity of the main blades, that is, the sensitivity of adjusting the amount of air passing through the duct during normal wind.

It is desirable that the predetermined angle be a slight angle that triggers the generation of lift force that the main blade receives. In addition, the main blade, which is rotatably provided around the main blade rotation axis, is set at a position rotated by a predetermined angle in the direction in which the amount of air passing through the duct during the normal wind is reduced as described above. As a result, even when headwind occurs,
It becomes easy to rotate in the direction of receiving the wind pressure and reducing the amount of air passing through the duct.

The invention according to claim 3 is, for example, as shown in FIGS.
As described above, in the damper (pressure loss reduction damper 1) according to claim 1 or 2, the amount of air passing through the duct a is almost zero due to the cooperation of the main blade 3 and the auxiliary blade 5 at the time of headwind. A main blade stopper 8 for stopping the rotation of the main blade 3 is provided at the position.

According to the third aspect of the invention, when headwind occurs,
By the cooperation of the main blade and the auxiliary blade, the rotation of the main blade is stopped by the main blade stopper at a position where the amount of airflow passing through the duct is almost zero. Therefore, by the cooperation of the main blades and the auxiliary blades, it is possible to prevent the main blades from rotating beyond the position where the air volume passing through the duct is substantially zero, and reliably prevent backflow. You can

As the main blade stopper, for example,
Examples thereof include screws and projecting pieces provided so as to project on the inner surface of the frame member.

The invention according to claim 4 is, for example, as shown in FIGS.
In the damper (pressure loss reduction damper 1) according to any one of claims 1 to 3, the duct a is formed by the cooperation of the main blades 3 and the auxiliary blades 5 during a back wind.
It is characterized in that an auxiliary blade stopper 9 for stopping the rotation of the auxiliary blade 5 is provided at a position where the amount of air passing through the inside is almost zero.

According to the invention described in claim 4, when headwind occurs,
Due to the cooperation of the main blade and the auxiliary blade, the rotation of the auxiliary blade is stopped by the auxiliary blade stopper at a position where the amount of air passing through the duct is substantially zero. Therefore, by the cooperation of the main blades and the auxiliary blades, it is possible to prevent the auxiliary blades from rotating beyond the position where the air volume passing through the duct is substantially zero, and reliably prevent backflow. You can

Examples of the auxiliary blade stopper include screws and protruding pieces provided on the inner surface of the frame member so as to protrude.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a damper according to the present invention will be described below with reference to FIGS.

First, as shown in FIGS. 1 to 7, the pressure loss reducing damper 1 according to the present invention is a cylindrical frame member 2 and a frame which form a part of the duct a by being connected to the duct a. A disk-shaped main blade 3 having a diameter corresponding to the inner diameter of the member 2 and a semi-disk-shaped auxiliary blade 5 having the same diameter as the main blade 3 are provided. Further, the auxiliary blade 5 is formed with a wind receiving portion 7 on the side that is on the windward side when the wind is normal, via support members 7a at both ends, and the wind receiving portion 7 together with the auxiliary blade 6 is rotated by the auxiliary blade. It is rotatable about the moving shaft 6.

The main blade 3 is mounted inside the frame member 2 via a main blade rotating shaft 4 which is orthogonal to the axial direction of the frame member 2, and smoothly rotates around the main blade rotating shaft 4. It is possible. A main blade stopper 8 is provided on the inner surface of the upper portion of the frame member 2, and the main blade 3 regulates clockwise rotation of the main blade 3 in a state where the main blade 3 closes the internal space of the frame member 2.

If the left side portion of the main blade 3 in FIG. 1 is the upper operating portion 3a and the right side portion is the lower operating portion 3b, the upper operating portion 3a side is the lower operating portion 3b.
The main blade rotating shaft 4 is set at a position slightly displaced from the center of gravity of the main blade 3 so as to be slightly heavier than the side. Therefore, in a windless state where the main blade 3 receives almost no wind resistance and when the air volume is small, the main blade 3 tries to rotate counterclockwise, but the upper operating portion 3a is lower than the lower operating portion 3b. A stopper 10 at the time of a slight air flow such as a screw is provided on the inner surface of the frame member 2 so as to regulate the rotation at a position which is slightly upward and inclined.

The auxiliary blade 5 is mounted inside the frame member 2 via an auxiliary blade rotating shaft 6 which substantially coincides with the main blade rotating shaft 4, and smoothly rotates around the auxiliary blade rotating shaft 6. It is possible. An auxiliary blade stopper 9 is provided on the inner surface of the lower portion of the frame member 2, and the auxiliary blade 5 counterclockwise rotates in a state where the auxiliary blade 5 closes a portion below the auxiliary blade rotation shaft 6 in the internal space of the frame member 2. The rotation of the is regulated. Therefore, the auxiliary blade 5 can be smoothly rotated in the region on the left side of the auxiliary blade stopper 9. The auxiliary blade 5 hangs downward from the auxiliary blade rotation shaft 6 until it receives a wind pressure of a certain value or more from the right side. Further, even if wind pressure is applied from the left side, the rotation is restricted by the auxiliary blade stopper 9.

Here, as described above, the upper operating portion 3a of the main blade 3 is set to be slightly heavier than the lower operating portion 3b so that the upper operating portion 3a side is lowered when there is no wind and when the air volume is small. However, this may be because the position of the main blade rotating shaft 4 with respect to the main blade 3 is set to be slightly deviated from the center of the main blade 3, or the upper operating portion 3a.
In addition, a weight (not shown) may be provided.

The operation of the pressure loss reducing damper 1 having such a configuration will be described in detail below. In the following,
The wind from the right side of the figure is referred to as normal wind, and the wind from the left side of the figure is referred to as headwind. Further, the description of the small air volume, the medium air volume, the large air volume, the air volume, and the wind is related to the normal wind.

<No wind and small air volume> Since the upper working part 3a side of the main blade 3 is heavier than the lower working part 3b side, the duct a
When the interior is calm or has a small air volume,
The main blade 3 is rotated counterclockwise until it comes into contact with the stopper 10 when a small amount of air flows, and as shown in FIG.
The upper operation part 3a is located slightly above the lower operation part 3b and is inclined. Further, the auxiliary vane 5 has not reached the critical air volume for separating from the auxiliary vane stopper 6, and the auxiliary vane 5 is still hanging down.
As a result, the wind blows through the upper space of the main blade 3. At this time, as can be seen from the relationship between the air volume and the pressure loss shown in FIG. 8, almost no pressure loss occurs inside the pressure loss reduction damper 1, and the wind has almost no resistance inside the pressure loss reduction damper 1. Can blow through.

<Transition from Small Air Volume to Medium Air Volume> When the air volume flowing through the inside of the duct a is increased and the small air volume is changed to the medium air volume, the auxiliary blade 5 and the auxiliary blade 5 are formed. The wind receiving unit 7 receives a wind pressure of a certain value or more from the right side. Then, as shown in FIG. 3, when the auxiliary blade 5 reaches the critical air volume that separates from the auxiliary blade stopper 9, the auxiliary blade 5 is rotated about the auxiliary blade rotation shaft 6.
Rotates clockwise, and a gap is created between the auxiliary blade 5 and the lower inner surface of the frame member 2. As a result, the wind blows through the upper space of the main blade 3 and the lower space of the auxiliary blade 4. Further, the main blade 3 is positioned such that the upper working portion 3a is located slightly above the lower working portion 3b and is inclined, and therefore, the upper space of the main blade 3 is inside the frame member 2. Is narrowed from the right side to the left side. As a result, the flow velocity of the wind passing through the upper space gradually increases from the right side to the left side, and a lift force larger than that acting on the lower operation part 3b acts on the upper operation part 3a.
Therefore, when the lift reaches the critical air volume for rotating the main blade 3, the main blade 3 rotates clockwise.

<Transition from Medium Air Volume to Large Air Volume> When the air volume flowing inside the duct a further increases and the medium air volume transitions to the large air volume, the auxiliary blade 5 as shown in FIG. Rotates further clockwise to increase the gap between the auxiliary blade 5 and the lower inner surface of the frame member 2, and the main blade 3 further rotates clockwise.

<Transition from a large air volume to a strong air volume> When the air volume flowing inside the duct a further increases and the air volume changes from the large air volume to the strong air volume, the main blade 3 further rotates clockwise. As a result, the main blade 3 is likely to hit the main blade stopper 8, and the amount of air passing above and below the main blade 3 is significantly reduced. Then, the lift received by the upper working unit 3a and the lower working unit 3b becomes smaller and the difference in the lifting forces also becomes smaller, and the main blade 3 slightly rotates counterclockwise and the air volume passing above and below the main blade 3 slightly. To increase. As a result, the upper operating portion 3a again receives a lift force, the main blade 3 rotates slightly clockwise, and the amount of airflow passing above and below the main blade 3 decreases. After that, these operations are repeated while gradually decreasing, and the air volume stabilizes (see FIG. 5).

<Backwind> In the case of backwind, as shown in FIG. 6, a wind trap is generated in the lower space of the upper operating part 3a, and the lower surface of the upper operating part 3a receives the wind pressure and rises up, and finally. As shown in FIG. 7, the main blade 3 rotates clockwise until it comes into contact with the main blade stopper 8, and the frame member 2 is closed by the main blade 3 and the auxiliary blade 5. Therefore, the amount of air passing through the duct a becomes almost zero, and the backflow is prevented.

According to this embodiment, the following effects can be obtained. The pressure loss reducing damper 1 adjusts the amount of air passing through the duct a within a predetermined range during normal wind, and
At the time of back wind, the amount of air passing through the duct a is set to almost zero to prevent back flow. At this time, even when the amount of air flowing into the duct a at the time of normal wind is relatively small, the passage area of the air flow in the duct a becomes large due to the air receiving portion 7, and therefore the wind speed becomes small, whereby The pressure loss coefficient is reduced, and the pressure loss in the duct a is reduced. Therefore, even when the amount of air flowing into the duct a is small, it is possible to improve the ventilation efficiency by efficiently using this amount of air. Further, since the pressure loss reducing damper 1 has the air flow rate adjusting damper and the backflow preventing damper integrated with each other and has a relatively simple structure, the manufacturing cost can be suppressed and the installation space can be reduced. Since the size is small, it is possible to increase the degree of freedom in the installation position.

Since the main blade 3 is held at a position rotated by a predetermined angle in a direction in which the amount of air passing through the duct a is reduced when the wind is normal, the main blade 3 is maintained when the wind is normal. Even when the air volume is relatively small,
It is possible to rotate by receiving lift. Therefore,
At the time of normal wind, the sensitivity of rotation of the main blade 3, that is, the sensitivity of adjusting the amount of air passing through the duct a can be improved to improve the ventilation performance.

At the time of headwind, the main blades 3 and the auxiliary blades 5 cooperate to prevent the main blades 3 from rotating beyond the position where the amount of airflow passing through the duct a is almost zero. It is possible to reliably prevent backflow.

At the time of headwind, the cooperation of the main blade 3 and the auxiliary blade 5 prevents the auxiliary blade 5 from rotating beyond the position where the amount of air passing through the duct a is almost zero. It is possible to reliably prevent backflow.

Although the frame member 2 has a cylindrical shape in the present embodiment, it may have an elliptic cylindrical shape or a rectangular cylindrical shape, and the main blade 3 and the auxiliary blade 5 have the same shape as the frame member 2. It can be appropriately changed according to the shape. Further, although the main blade 3 has a disc shape, it may have an elliptical plate shape. Further, the auxiliary blade 5 may also have a shape obtained by dividing an elliptical plate into two.

<Modification> A modification of the present embodiment will be described with reference to FIGS. 9 to 11. The same components as those of the present embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The air receiving portion 7 may be formed by appropriately bending or bending as shown in FIGS. 9 (a) and 9 (b).

The upper operation section 3a and the lower operation section 3b are
As shown in FIGS. 10 (a) and 10 (b), the angle may be set appropriately.

[0046]

According to the invention described in claim 1, the damper adjusts the amount of air passing through the duct within a predetermined range during normal wind, and substantially reduces the amount of air passing through the duct during back wind. Set to zero to prevent backflow. At this time, even when the amount of air flowing into the duct at the time of normal wind is relatively small, the air receiving area increases the passage area of the air flow in the duct, and thus the wind speed decreases, which results in a pressure loss coefficient. Becomes smaller and the pressure loss in the duct is reduced. Therefore, even when the amount of air flowing into the duct is small, it is possible to improve the ventilation efficiency by efficiently using this amount of air. Further, since the damper has an air flow adjustment damper and a backflow prevention damper integrated with each other and has a relatively simple structure, the manufacturing cost can be suppressed and the installation space can be small. Therefore, it is possible to increase the degree of freedom of the position where it is provided.

According to the second aspect of the invention, the same effect as that of the first aspect of the invention can be obtained, and in addition, the main blades have an amount of air which passes through the duct when there is no wind and when the wind is normal. Since the main blades are held at a position rotated by a predetermined angle in the direction of decreasing, the main blades can be rotated by receiving lift even when the air volume is relatively small during normal wind. Therefore, the ventilation performance can be improved by improving the rotational sensitivity of the main blades, that is, the sensitivity of adjusting the amount of air passing through the duct during normal wind.

According to the third aspect of the invention, the same effect as that of the first or second aspect of the invention can be obtained. Of course, at the time of headwind, the main blade and the auxiliary blade cooperate with each other. It is possible to prevent the main blade from rotating beyond the position where the air volume passing through the duct is substantially zero, and it is possible to reliably prevent backflow.

According to the invention described in claim 4,
The same effect as that of the invention described in any one of 3) can be obtained, and the position where the amount of air passing through the duct is almost zero by the cooperation of the main blades and the auxiliary blades at the time of headwind. It is possible to prevent the auxiliary blade from rotating beyond the above range, and it is possible to reliably prevent backflow.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a pressure loss reducing damper according to the present invention.

FIG. 2 is a model diagram showing a state of blades at a small air volume in the embodiment of the pressure loss reducing damper according to the present invention.

FIG. 3 is a model diagram showing a state of blades when the air volume is medium.

FIG. 4 is a model diagram showing a state of blades when a large air volume is supplied.

FIG. 5 is a model diagram showing a state of the blade when the amount of strong wind is the same.

FIG. 6 is a model diagram showing the state of the blades during headwind (initial).

FIG. 7 is a model diagram showing a state of blades in the case of headwind.

FIG. 8 is a diagram showing a relationship between air volume and pressure loss.

FIG. 9 is a diagram showing a modified example of the shape of the air receiving part in the embodiment of the pressure loss reducing damper according to the present invention.

FIG. 10 is a diagram showing a modified example of the angles of the upper operation unit and the lower operation unit.

FIG. 11 is a perspective view showing a conventional damper.

FIG. 12 is a model diagram showing the state of the blades of the conventional embodiment of the damper when the air volume is small.

FIG. 13 is a model diagram showing a state of the blade when the air volume is medium.

FIG. 14 is a model diagram showing the state of the blades when the air volume is large.

FIG. 15 is a model diagram showing the state of the blade when the amount of strong air is the same.

FIG. 16 is a model diagram showing the state of the blades when headwind (initial).

FIG. 17 is a model diagram showing a state of blades in the case of headwind.

[Explanation of symbols]

1 Pressure loss reduction damper 2 frame members 3 main wings 4 Main blade rotation axis 5 auxiliary blades 6 Auxiliary blade rotation axis 7 Wind receiver 8 Main blade stopper 9 Auxiliary blade stopper 51 Pressure loss reduction damper 61 Pressure loss reduction damper 71 Pressure loss reduction damper 81 Pressure loss reduction damper a duct

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yasuyuki Kobayashi 1-20-10 Toranomon, Minato-ku, Tokyo Nishimatsu Construction Co., Ltd. (72) Inventor Masaki Kojima 1-20-10 Toranomon, Minato-ku, Tokyo Nishimatsu Construction Incorporated (72) Inventor Naohiro Yoshida 1-20-10 Toranomon, Minato-ku, Tokyo Nishimatsu Construction Co., Ltd. (72) Inventor Toshio Sadamasa 2-22 Jonanjima, Ota-ku, Tokyo Unix Co., Ltd. (72) Inventor Osamu Oguni 2-2-2, Jonanjima, Ota-ku, Tokyo Inside the stock company Unix (56) Reference JP 2000-274797 (JP, A) Actual development Sho 59-123240 (JP, U) ) Registered utility model 3004775 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F24F 13/14 F24F 13/10 F24F 7/00 F24F 7/04

Claims (4)

(57) [Claims] 1. A damper which is attached to a duct and adjusts the amount of air passing through the duct, the frame member forming a part of the duct by being connected to the duct, and in the axial direction of the duct. A main blade that is rotatable about an orthogonal main blade rotation axis, an auxiliary blade that is rotatable about an auxiliary blade rotation axis that substantially coincides with the main blade rotation axis, and the auxiliary blade is provided. A wind receiving portion that acts so as to rotate in a direction of increasing the amount of air passing through the duct by receiving wind pressure during normal wind, and the wind receiving portion receives wind pressure during normal wind. The auxiliary blade rotates in a direction to increase the amount of air passing through the duct, and the main blade receives lift as the amount of air flowing into the duct increases, and the main blade passes through the duct. Rotate in the direction to reduce the air volume By Rukoto,
The amount of air passing through the duct is adjusted within a predetermined range, and at the time of headwind, the auxiliary vanes cooperate with the main vanes that rotate in a direction that receives wind pressure and reduces the amount of air passing through the duct, A damper characterized in that the amount of air passing through the duct is made substantially zero to prevent backflow. 2. The damper according to claim 1, wherein the main blades are held at a position rotated by a predetermined angle in a direction in which the amount of air passing through the duct is reduced in normal wind when there is no wind. Damper to be. 3. The damper according to claim 1 or 2, wherein the main blades and the auxiliary blades cooperate with each other when headwind occurs.
At the position where the air volume passing through the duct is almost zero,
A damper comprising a main blade stopper for stopping the rotation of the main blade. 4. The damper according to claim 1, wherein the main blade and the auxiliary blade cooperate with each other when headwind occurs.
At the position where the air volume passing through the duct is almost zero,
A damper comprising an auxiliary blade stopper for stopping the rotation of the auxiliary blade.