JP2920739B2 - Backflow prevention damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airflow path provided in an air flow path, in which an internal blade is opened only in a certain direction of the airflow, and an airflow is automatically generated in the opposite direction. The present invention relates to a backflow prevention damper that shuts off, and more particularly to a backflow prevention damper that performs a highly efficient air flow supply and cutoff function by minimizing pressure loss during opening and closing movement of a blade body.

[0002]

2. Description of the Related Art Conventionally, in a high-rise building or a building for commercial use, a backflow prevention damper is arranged at a predetermined position of an air-conditioning duct to cut off ventilation of conditioned air and warm / cool air. I have. This backflow prevention damper opens the flow path by pivotally supporting the blade body in the casing so that it can rotate in one direction of the air flow, and the blade body cannot rotate with respect to the air flow from the opposite direction. The casing is closed by providing a stopper as follows. In such a backflow prevention damper, a rotating shaft is rotatably supported at the upper end of the casing, one end surface of the damper blade is fixed to the rotating shaft, and the other end is downwardly supported in a downward manner. In addition, the air flow is opened to a certain direction, and the flow path is completely closed at a position orthogonal to the flow to shut off the ventilation of the air. On the other hand, recently, a smoke-prevention method has been adopted to pressurize corridors, ancillary rooms, etc. to prevent the infiltration of smoke and to secure evacuation places for evacuees while sending fresh air. To prevent
If the vestibule side is set to an excessively high pressure, it is necessary to maintain the air pressure at a necessary limit compared to the compartment outside the vestibule due to problems such as the doors entering the vestibule side cannot be opened. A backflow prevention damper may be used to adjust the pressure between adjacent spaces. In such a case, for example, a communication passage communicating between the annex room and the room outside the annex room is formed in the wall, and a backflow prevention damper is disposed in the middle of the wall for air relief, or attached to the door itself. In such a case, the casing of the damper must be disposed so as to be embedded in a wall or a door.

[0003]

In the above-mentioned conventional backflow prevention damper, in the case of a backflow prevention damper of the type supported at the upper end side of the casing, a process of opening the blades from the fully closed state and gradually increasing the opening degree. Thus, the lower end of the blade rotates while drawing an arc-shaped locus. On the other hand, the bottom wall in the casing is straight and straight. Then, after the operation of starting to open the blades, once the blades are pushed open, it is necessary to shift to a movement for opening the flow path corresponding to the wind pressure. In this case, due to the weight of the blade itself, even when the blade is fully opened, the lower end portion of the blade has to be fully opened at a position inclined so as to obliquely obstruct the flow path. Therefore, accurate pressure adjustment cannot be performed due to the large pressure loss.For this reason, for example, when used as air pressure relief at the time of pressure adjustment, a large number of conventional backflow prevention dampers are provided at a plurality of locations. It has to be installed, and there has been a problem that equipment costs and construction costs are significantly high. In addition, in the pressurized smoke prevention method that pressurizes the annex rooms to prevent the invasion of smoke, it is necessary to install them in a wall or an opening / closing door, and in such a case, it is necessary to install a balance weight or the like outside the damper. Therefore, there is no backflow prevention damper that can cope with such a smoke exhaust system, and its development has been long-awaited.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to support a vane body that freely rotates from a fully closed state to a fully open state with respect to a unidirectional air flow. With the backflow prevention damper, the pressure loss can be minimized in the fully opened state from the opening operation, and high-precision backflow prevention inside even in places where it is difficult to project to the outside by the pressurized smoke prevention system. It is an object of the present invention to provide a backflow prevention damper capable of performing a pressure adjusting function.

[0005]

In order to achieve the above-mentioned object, the present invention provides a casing 1 provided in an air flow path.
2, a rotating shaft 14 rotatably provided so as to cross the inside of the casing 12, and fixed to the rotating shaft 14,
A blade body 16 provided to open the flow path only in a constant flow direction of air and to close the flow path in the reverse flow direction;
The casing 12 has an arc-like shape along the rotation locus with a gap H with respect to the rotation locus of the lower end of the blade when the blade 16 rotates in the opening direction from the closed state. Of the backflow prevention damper 10 provided with the air guide plate 84 of FIG.

Further, in the backflow prevention damper of the second aspect, the baffle plate 84 is connected to the bottom wall 12 of the casing 12.
a and may be formed of a plate member so as to form a substantially triangular cross section with the bottom wall 12a.

[0007] In the backflow prevention damper of the third aspect, the rotating shaft 14 is provided on the upper wall 12b of the casing 12.
And a balance weight 86 may be provided at the upper end side of the blade body 16 attached to the rotating shaft 14.

Further, in the backflow prevention damper according to the fourth aspect, the blade body 16 is attached so as to follow a tangent to the peripheral surface of the rotating shaft 14 and to follow a tangent on the downstream side in the fully closed state. It may be provided.

[0009]

In the backflow prevention damper according to the first aspect of the present invention, a casing provided in the air flow path, a rotating shaft rotatably provided to traverse the casing, and the rotating shaft And a blade body provided so as to open the flow path only in a constant flow direction of air and close the flow path in the reverse flow direction, and the casing includes:
When the blade rotates in the opening direction from the closed state, an arc-shaped air guide plate is provided along the rotation locus with a gap to the rotation locus of the lower end of the blade. An air guide plate is installed on the bottom wall of the casing on the downstream side of the airflow, and the air guide plate is provided so as to rise up in an arc shape and further along the rotation trajectory of the blade body. There is no play in the flow, the blade body efficiently receives the air flow from the upstream (forward flow) side, smoothly opens and operates, and once opened, it is in a state parallel to the flow at a stretch and becomes fully open. In addition, since the upward air current is guided by the arcuate air guide plate and the force for constantly pushing up the lower end of the blade body continues to act, the state parallel to the flow can be maintained, and therefore, the pressure loss when fully opened is greatly reduced. .

In the backflow prevention damper according to the present invention, the air guide plate is formed so as to rise in an arc shape from the bottom wall of the casing, and forms a substantially triangular cross section with the bottom wall. It is formed of a plate member. Since the plate member is formed in a substantially triangular shape, the installation is easy, and the plate member can be easily attached to the damper already installed in the duct. In addition, the construction work is simple because it is lightweight and easy to handle.

In the backflow prevention damper according to a third aspect of the present invention, the rotating shaft is mounted at a position spaced a predetermined distance from an upper wall of the casing, and the upper end of the blade body mounted on the rotating shaft. Is provided with a balance weight. By attaching the balance weight directly to the blade body, the action of the balance weight can be made to function directly, and a rod or the like for attaching the weight is unnecessary. For adjusting the balance weight, for example, the closing force of the blade body is adjusted by moving the weight portion up and down. Since the weight is provided at the position of the upper end of the blade in the direction of rotation, the weight is at the inner position of the casing. In some cases, malfunction of the blade body due to malfunction due to damage or obstacles in the vicinity does not occur.

Further, in the backflow prevention damper according to claim 4, the blade body is attached so as to be along a tangent to the peripheral surface of the rotating shaft, and is provided so as to be along a tangent on the downstream side in the fully closed state. Have been. If the balance weight is attached to the upper end on the upstream side of the blade, a certain amount of closing force is always applied to the downstream side by installing the blade along the tangent on the downstream side of the flow of the peripheral surface of the rotating shaft. Therefore, it is easy to adjust the closing force of the blade body.

[0013]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 4 show a backflow prevention damper 10 according to an embodiment of the present invention. In the present embodiment, the backflow prevention damper 10 includes an opening / closing lock plate that forcibly closes and locks the blade body when a fire occurs,
It is formed as a smoke and fire protection / backflow prevention damper that can also function as a fire protection damper.

As shown in FIG.
Is a casing 12 having a rectangular cross section and the casing 1
The rotary shaft 14 is rotatably supported at both upper and lower sides of the rotary shaft 2, and a blade 16 fixed to the rotary shaft 14. The blade 16 is formed in a rectangular shape corresponding to a rectangular flow path in the casing 12. The blade 16 is provided so as to open the flow path only in a constant flow direction of air and close the flow path in the reverse flow direction.

As shown in FIG. 1, the upper inner surface of the casing 12 above the rotary shaft 14 has an upper stopper 18a which comes into contact with the upper rear surface of the blade body 16 and the rear surfaces of both side ends.
Is fixed, and the casing 12 is located below the rotation shaft 14.
A lower stopper 18b is fixed to the lower inner surface of the lower surface of the blade body 16 so as to contact the lower front face and the front sides of the blade body 16 so that the lower end portion of the blade body 16 rotates freely in the rear direction with respect to the airflow from the front. The path is opened, and the blade body 16 is prevented from rotating by stoppers 18a and 18b against the airflow from the back, and the flow path is closed.

Further, in this embodiment, on the right side of the casing 12, when smoke or a flame flowing in the casing 12 is detected at the time of a fire, the blade 16 is forcibly operated to close and lock the flow path. The opening / closing lock plate 20 is fixed.

As shown in FIGS. 1 and 5, a box-shaped board 22 is fixed to the outside of the casing 12. This board 22
Is formed in a box shape whose middle is partitioned by a middle receiving plate 32. The open / close lock plate 20 is located below the side of the plate 22 and has a temperature fuse 24 protruding and fixed at one end into the casing 12.
A biasing mechanism 28 having an operating shaft 26 pivotally supported by the board 22 so as to be rotationally biased in one direction in conjunction with
As shown in the figure, the end of the operating shaft 26 of the urging mechanism 28 and the end of the rotary shaft 14 of the blade 16 are interposed, and the blade 16 is always in the flow path from the fully closed state to the fully open state. A lock mechanism 30 is provided for holding the rotation of the blade 16 in the fully closed state of the flow path in conjunction with the melting operation of the temperature fuse 24 while freely rotating.

5 and 6, the urging mechanism 28
Has an operating shaft 26 which is supported by a bearing plate 34 fixed to the panel 22. A circular plate-shaped stopper 36 is fixed at an axially intermediate position of the operating shaft, and its end is It protrudes from the middle receiving plate 32. At both ends of the circular arc of the stopper 36, cut grooves 36a and 36b are formed in a concave shape. On the other hand, an L-shaped lock arm 42 in which a base end is pivotally mounted 38 and a roller 40 which engages with the cut grooves 36a and 36b of the stopper 36 is pivotally supported on the lower surface of the tip end in the same board 22.
Is provided. Further, a pin 44 is fixedly provided upright above the distal end of the lock arm 42.
And the upper end of the lock arm 42 have two link levers 4.
6a, 46b.

As shown in FIG. 6, both link levers 46
The ends of a and 46b are pivotally connected to a pin 44 and an upper end pin of the lock arm 42, respectively, and both link levers are pivotally connected by a common shaft 48.

As shown in FIG. 5, a plunger 52 with a spring of an electromagnet 50 is provided on the upper left side of the same plate 22, and the tip of the plunger 52 is engaged with the common shaft 48. I have. And the plunger 5 is always used by the spring.
2 is urged in the spring extension direction. In addition, the electromagnet 50 is connected to a temperature sensor provided on a flow path (not shown). Further, the upper end of the fuse lever 54 is pivotally connected to the pin 44, and a cut groove 56 at the lower end of the fuse lever 54 is detachably engaged with the pin of the temperature fuse 24.

As shown in FIG. 5, the fuse lever 5 is located near the position where the fuse lever 54 is pivotally attached to the pin 44.
4, an operation pin 58 is provided upright in the rear direction in the drawing. A pulling spring 60 is extended from the board 22 at an intermediate position of the fuse lever 54. As a result, as shown in FIGS. 7 and 8, when the operating shaft 26 is rotated 90 degrees counterclockwise by the handle 62 fixed to the end of the operating shaft 26, the lock arm 42 is inserted into the cut groove 36 a of the stopper 36. Link levers 46a and 46b with rollers 40 engaged and pressed upright by a plunger 52 with a spring
The roller 40 of the lock arm 42 is
Will be locked and held.

On the other hand, as shown in FIGS.
A spiral spring 6 is provided on the outer periphery of the distal end of the operating shaft 26 projecting from
The spiral spring 64 urges the spiral spring 64 to rotate clockwise in FIG. Therefore, the operating shaft 26 is always biased to the position of the stopper 36 in FIG. 8 (when the blade 16 is locked to close the flow path as described later), and the handle is pressed against the rotational biasing force of the spiral spring 64. FIG.
The operating shaft is rotated to the position and locked by the stopper 36,
The blade body 16 is set in the free rotation state from the fully closed state to the fully opened state of the flow path. Thus, the urging mechanism 28
Are the operating shaft 26, stopper 36, lock arm 42, link levers 46a and 46b, plunger 52 with spring,
The urging mechanism includes a fuse lever 54, a spiral spring 64, and the like. However, the urging mechanism is not limited to this structure, and always urges the operating shaft in one rotation direction to stop the urging operation. Any mechanism may be used as long as the mechanism is configured to cancel the operation and rotate the operation shaft.

As described above, the lock mechanism 30 is provided between the end of the operating shaft 26 and the end of the rotary shaft 14 of the blade 16. 9 to 14, the lock mechanism 30
Is a spacer 66 detachably fitted to the end face of the operating shaft 26.
And a projection 68 protruding from the rotation shaft 14 and fixed.

In FIG. 13, a plate 70 is fixed to one end of the rotating shaft 14 protruding from the casing 12,
Two projections 68, 68 protrude from the plate piece 70 at positions symmetrical with respect to the rotation shaft 14. Further, the protrusion 6
A cylindrical body 72 is fixed at substantially the same height as the projecting heights of 8, 68. The tip of the rotating shaft 14 further projects from the cylindrical body 72 to form a shaft piece 14a.

On the other hand, the spacer 66 has a ring-shaped spacer 76 having a hole 74 into which the shaft piece 14a is fitted as shown in FIGS. It has a pair of engagement projections 78, 78 protruding from the housing. A projection 80 is provided on the other side of the spacer 76 so as to project therefrom. The projection 80 fits into a groove 82 formed on the end face of the operating shaft 26, and the spacer 66 and the operating shaft 26 are joined together. It will rotate. Therefore, the spacer 66 is provided with the engagement protrusion 7.
8, 78 are set toward the rotating shaft 14 side.

The pair of engaging projections 78, 78
As shown in FIG. 7, the operation shaft 26 is engaged with the projections 68 fixed to the rotation shaft side when the operation shaft 26 is rotated. Thereby, as described later, the urging mechanism is set and held so that the engaging projections 78 and 78 are located within a range of about 90 degrees from the fully closed state of the rotary shaft 14 to the fully opened state of the operating shaft 26 as described later. In the same range, the rotation shaft 14 is freely rotated.

One characteristic of the present invention is that an arc-shaped air guide plate 84 is provided on the casing 12 so as to follow the arc-shaped rotation locus of the lower end of the blade body 16. In FIG. 4, the casing 12 has a gap H with respect to the rotation locus of the lower end of the blade 16 when the blade 16 rotates from the closed state to the open direction by the airflow from the right direction in the figure. An arcuate air guide plate 84 is attached along the rotation locus.

In the embodiment, the air guide plate 84 is viewed from the side.
Alternatively, the casing 12 is provided with an arc surface 84a having an arc shape in cross section, is formed so as to rise in an arc shape from the bottom wall 12a of the casing 12, and is formed of a plate member so as to form a substantially triangular shape in cross section with the bottom wall 12a. ing. That is, the upper end portion 84b of the arc-shaped air guide plate 84 is arranged so as to rise from the bottom wall 12a to an appropriate height.
The support plate 85 is provided upright in the lower part of the base 4b to support the baffle plate 84, and is guided in a substantially triangular shape (three-dimensionally, a triangular prism having a circular arc surface on one side). The wind plate 84 is provided near the rotation locus of the blade body 16.

Therefore, the air guide plate 84 is basically a circular plate, and has a simple structure and a low cost. Like the casing 12, it may be formed of a metal plate. Further, a backflow prevention damper having no air guide plate can be easily installed when necessary. This air guide plate 8
4 keeps a state where a constant gap is maintained in an arc shape with the rotation trajectory of the blade body 16 when the blade body rotates, so that the play of the air flow at the start of opening of the blade body 16 is reduced, and the pressure loss is reduced. And the blade can be smoothly and efficiently rotated. That is, it freely and smoothly rotates with respect to the airflow from the forward flow direction.

When the wing 16 is fully opened, that is, in a state parallel to the direction of air flow, the air from the forward flow direction is curved by the arc of the air guide plate 84. It is guided by the surface 84a and rises in an arc shape.
Then, together with the airflow in the forward flow direction, a force is applied to the blade body so as to always lift the lower end upstream side of the blade body 16 and keep the blade body 16 parallel to the flow. Thereby, the pressure loss can be extremely reduced in the fully opened state of the blade body, and a highly accurate air flow corresponding to the capacity of the duct can be passed. In this way, the pressure loss when fully opened is extremely small, and the air relief function required especially on the high pressure side such as an annex room can be performed accurately and efficiently, so the number of backflow prevention dampers to be installed is minimized. Also, installation and construction costs can be kept low. Maintenance and inspection are also easy.

In this embodiment, as shown in FIG.
The rotating shaft 14 is rotatably mounted at a position spaced a predetermined distance from the upper wall 12b of the casing 12. Further, a balance weight 86 is attached to the flow upstream side surface of the blade body 16 corresponding to the interval S.

As shown in FIG. 1, the balance weight 8
6 is a U-shaped rod 8 attached to the front face of the upper end portion of the blade body 16 in the rotation direction.
8 is mounted on a shaft 90 so as to be vertically adjustable. The balance weight 86 balances the rotation of the blade body 16 due to the airflow, and moves the balance weight 86 up and down when an excessive closing force is applied to the flow path in the casing due to the weight of the blade body. 16 can be smoothly rotated by balancing the rotation. Since the weight 86 is mounted in the flow path, that is, on the blade body 16, it can be directly embedded in the wall of the building or the door itself.

When it is necessary to embed the device in the wall of a building or install it directly on an opening door by, for example, a pressurized smoke prevention method, the balance weight or counterweight of the backflow prevention damper is provided outside the casing. In particular, the configuration according to the present embodiment is effective because it is impossible to arrange them.

Further, in the embodiment, the rotating shaft 14 is positioned at a distance S from the upper wall 12b of the casing 12.
Therefore, when the blades 16 are not fully parallel to the air flow when the blades 16 are fully opened, air vortices and turbulent flows are generated downstream of the blades at the interval S, and not only noise is generated. What causes a large pressure loss is that the installation of the air guide plate 84
The guiding action by 4a surely keeps the blade body 16 fully open in a state parallel to the flow, so that a particularly excellent effect is obtained for the relief action of the compressed air.

Further, in the embodiment, the blade body 16 is attached along a tangent to the peripheral surface of the rotating shaft 14 and
It is provided along the tangent line on the downstream side in the fully closed state. As described above, since the rotating shaft 14 is fixed not along the center of the rotating shaft 14 but along the tangent of its peripheral surface, a closing force due to its own weight of the blade body is applied in advance. Therefore, the balance weight 84 is provided at the upper end side on the upstream side of the blade body flow.
When the is mounted, the rotational moment is offset to some extent, and the balance can be easily adjusted.

In the figure, reference numeral 92 denotes a manual operation lever for operation check and the like, the lower end of which is brought close to the common shaft 48 between the link levers 46a and 46b and the intermediate position is pivotally mounted near the pin 44. Yes, the lower end is always the common shaft 48
When the rotating shaft 14 rotates, the rotating shaft 14 is pressed against the common shaft 48 to break the link and rotate the rotating shaft.

Next, the function of the backflow prevention damper for both smoke prevention and fire prevention according to the present embodiment will be described. First, in a state where the engagement between the fuse rod of the temperature fuse 24 and the cut groove 56 of the fuse lever 54 is released, FIG. Eighth stopper 36
In the position indicated by the solid line, the blade 16 in the flow path fixed to the rotating shaft 14 is fully closed in the flow path as shown in FIG. At this time, the operating shaft is strongly urged clockwise by a spiral spring 64 fixed to the operating shaft 26, and the roller 40 at the lower end of the lock arm 42 is fitted into the cut groove 36b of the stopper 36 to lock the shaft. Holding. At this time, the engagement protrusions 78 of the spacer 66 fitted to the end of the operation shaft 26 are held at, for example, the positions shown by solid lines in FIG.
The protrusions 68, 68 fixed to the ends of the blades restrict the rotation of the blade body 16 in the rotation direction, that is, the counterclockwise rotation in the drawing, and lock and hold the flow path closed state of the blade body. In this case, when the engagement between the temperature fuse 24 and the fuse lever 54 is released due to the melting of the fuse, a high temperature airflow flows through the flow path due to the occurrence of a fire or the like, and the state functions as a smoke prevention and a fire prevention damper.

Next, when the return lever 92 is rotated clockwise in FIG. 5 and its lower end is pushed to the vicinity of the common shaft 48 to rotate the handle 62 while folding the link, the end of the lock arm 42 is rotated. The portion is pushed upward and the roller 40 slips off from the cut groove 36b of the stopper 36. Stopper 36
Roller 40 is rolled along the arc of FIG.
The end roller 40 of the lock arm 42 is fitted in the cut groove 36a of the stopper 36 as shown in FIG. Thereafter, the cutting groove 56 of the fuse lever 54 is engaged with the fuse rod of the temperature fuse 24 to obtain a biasing state of the operating shaft 26 in one rotation direction by the biasing mechanism 28. At this time, in FIG. 13, the spacer 66 of the lock mechanism 30 holds the engagement projections 78, 78 rotated counterclockwise by approximately 90 degrees from the position shown by the solid line to the position shown by the chain line. . Therefore, in this state, the projections 68, 68 fixed to the rotating shaft 14 are free to rotate counterclockwise from the position indicated by the solid line to the position indicated by the dashed line in FIG. The body 16 opens and closes from the fully closed channel to the fully opened state. put it here,
The blade body 16 opens the flow path only in the direction of the arrow and functions as a backflow prevention damper.

At this time, when the thermal fuse 24 protruding into the flow path is melted by a high-temperature airflow at the time of a fire or the like, a fuse rod having a known fuse mechanism retreats, and the thermal fuse is removed from the cut groove 56 of the fuse lever 54. Withdrawal,
This causes the entire fuse lever 54 to rotate clockwise about the pin 44 via the pull spring 60 as shown in FIG. Then, the operation pin 58 also rotates in the same direction, and the link arm 46a, 46b is pressed against the elasticity of the spring-loaded plunger 52 to bend leftward in the drawing, so that the lock arm 42 is pulled upward. Roller 4 of the same lock arm
0 is separated from the cut groove 36a of the stopper 36, and the operating shaft 26 is instantaneously rotated clockwise by the spiral spring 64 that urges the operating shaft 26, and the state shown in FIG.

As described above, the urging force of the urging mechanism 28 acts to rotate the operating shaft 26 clockwise by 90 degrees, and the engaging projections 78 of the spacer 66 of the lock mechanism 30
While rotating the blade body 16 by engaging with the projections 68 on the fourth side, the blade body 16 is brought into contact with the upper and lower stoppers 18a and 18b in the casing 12, and the blade body 16 forcibly closes the flow path. It locks and operates as a smoke and fire damper. The operating shaft 26 senses a predetermined high temperature not only by the melting action of the thermal fuse 24 but also by a temperature sensor provided on the flow path side (not shown) to operate the electromagnet 50 and resist the urging force of the spring of the plunger 52 with spring. It also operates by retracting the plunger rod of the electromagnet.

The engagement projections 78, 78 of the lock mechanism 30
The projections 68 and 68 are provided in pairs in the embodiment. However, the present invention is not limited to this. The projections may be engaged one by one.
As shown in FIG. 7, a disk 94 is fixed to the rotating shaft 14 side, a circumferential groove 96 is provided in the disk 94, and the disk 94 is fitted to an engaging projection 78 protruding from the spacer 66 of the operating shaft 26. good. The smoke and fire protection / backflow prevention damper of the present embodiment can be installed in a duct or the like communicating with a wall or the like to an emergency escape staircase or the like of a building to perform safe evacuation guidance in the event of a fire.

When the blade body 16 functions as a backflow prevention damper, the balance is adjusted when air flows in the flow path P as shown by the arrow from the right side, which is the upstream side to the left side, which is the downstream side in FIG. The lower end of the blade is pushed against the closing force of the blade 16 to open the blade. At this time, since the gap is constant when the blade body 16 rotates in an arc when the blade body 16 starts to open from the fully closed state by the air guide plate 84, the air pressure efficiently acts on the blade body, and smoothly and promptly. Start open. Then, once opened, the airflow rises along the arc surface of the air guide plate 84a and acts in the direction of lifting the lower end of the blade body 16, so that the blade 16 is fully opened at a stretch. At this time, the blade 16 is not shown, but is substantially in parallel with the flow of air. Further, the airflow is always an arc-shaped ascending airflow along the arc surface 84a, and the airflow always acts to lift the lower end side of the blade body 16, so that the parallel state of the airflow of the blade body is reliably maintained. Becomes

As a result, the pressure loss at the beginning of opening is reduced to perform a smooth opening operation, and after opening, the opening is fully opened at a stretch, and furthermore, the parallel state with the air flow is maintained. Therefore, for example, when the air pressure relief function is performed, the number of dampers to be installed can be kept to a minimum, and the equipment cost can be kept low. In addition, the manufacturing cost of the main body of the damper is low because the structure is extremely simple, and it can be easily installed later even after installing a damper that does not have a wind guide plate, making it a versatile damper. It can be configured.

The adjustment of the closing force by the weight of the blade body can be easily performed by adjusting the balance weight 86 up and down. Further, the adjustment itself by the vertical movement can be easily and reliably performed in combination with the balance weight attached on the upstream side since the blade body is attached on the downstream side of the flow on the peripheral surface of the rotating shaft.

The backflow prevention damper of the present invention is not limited to the configuration of the above-described embodiment, and may be arbitrarily modified without departing from the spirit of the invention described in the claims. The backflow prevention damper may be an ordinary backflow prevention damper having a backflow prevention function such as a stopper without a sensor or a forced flow path closing mechanism, instead of a smoke prevention and fire prevention damper.

[0046]

As described above, the backflow prevention damper according to the first aspect of the present invention is provided so as to be rotatable so as to traverse the casing provided in the air flow passage and inside the casing. A rotating shaft, and a blade fixed to the rotating shaft and provided so as to open the flow path only in a constant flow direction of air and close the flow path in the reverse flow direction, and the casing has When the blade rotates in the opening direction from the closed state, an arc-shaped air guide plate is provided along the rotation locus with a gap with respect to the rotation locus of the lower end of the blade. In the fully open state of the blade body, it is kept almost completely parallel to the air flow, and the pressure loss at the time of full open can be greatly reduced, so that not only is it possible to adjust the flow rate with high accuracy corresponding to the duct capacity, In particular, a quick air pressure relief function from the high pressure side is required. And often a necessary minimum installation number of the backflow prevention damper is if it is, it is possible to save a large overall equipment cost. In addition, when performing smoke and fire prevention by the pressurized smoke prevention method, it is inevitable to install the wall or door in a buried manner, so that the air guide function of the air guide plate can be made to function effectively.

According to the backflow prevention damper of the present invention, the air guide plate is formed so as to rise in an arc shape from the bottom wall of the casing, and forms a substantially triangular cross section with the bottom wall. Since it is formed of a plate member,
Basically, the baffle plate is simply made of an arc-shaped plate, so the structure is simple and the cost is inexpensive, and the backflow prevention damper without the baffle plate is installed. Can also be easily installed.

Further, according to the backflow prevention damper according to claim 3, the rotating shaft is mounted at a position spaced a predetermined distance from the upper wall of the casing, and the upper end of the blade body mounted on the rotating shaft. The balance weight is provided on the side, so that the balance weight is located inside the casing, so that there is nothing protruding outside the casing, and therefore, the building wall embedded type in a pressurized smoke prevention system or the like can be used. Or, even when it is necessary to directly install the balance weight on the door, it is possible to mount the balance weight easily and at the same time, it is possible to make the balance weight function effectively.
In particular, since the blades are kept fully open so as to be parallel to the air flow due to the rising action of the arc-shaped air flow of the baffle plate, there is almost no pressure loss, and therefore, the wall embedded type, the closing force of the blades And the pressure loss can be reduced at the same time, and a backflow prevention damper particularly effective in a pressurized smoke prevention system can be constructed. In addition, it is generally possible to reliably prevent malfunction of the blade body and poor closing.

Further, according to the backflow prevention damper according to the fourth aspect, the blade body is mounted so as to follow the tangent to the peripheral surface of the rotating shaft, and to follow the tangent on the downstream side in the fully closed state. Since it is provided, a closing force is always applied to the blade body on the flow path closing side, and a balance weight is installed on the upstream side of the flow, so that the closing force balance can be adjusted smoothly and easily. .

[Brief description of the drawings]

FIG. 1 is a front view of a backflow prevention damper according to an embodiment of the present invention.

FIG. 2 is a right side view thereof.

FIG. 3 is a plan view thereof.

FIG. 4 is a longitudinal sectional operation explanatory view showing a state in which a flow path is closed by a blade body and the blade body starts to open.

FIG. 5 is an enlarged front view showing the inside of the lock plate.

FIG. 6 is a view taken along line AA of FIG. 5 showing a link lever portion.

FIG. 7 is an operation explanatory view of an urging mechanism in the opening / closing lock panel.

FIG. 8 is an operation explanatory view of an urging mechanism in the opening / closing lock panel.

FIG. 9 is an enlarged cross-sectional view of a lock mechanism linked to an end of the rotary shaft of the blade body and an end of the operating shaft of the lock plate.

FIG. 10 is an enlarged sectional view of a state where a lock mechanism is separated.

FIG. 10 is a view taken in the direction of arrows BB in FIG. 10;

FIG. 12 is a view taken along line CC in FIG.

FIG. 13 is a view taken along the line DD in FIG.

FIG. 14 is an exploded perspective view of the lock mechanism.

FIG. 15 is an enlarged perspective view showing a lock mechanism of another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Backflow prevention damper 12 Casing 14 Rotating shaft 16 Blade body 30 Lock mechanism 36 Stopper 54 Fuse lever 84 Wind guide plate 86 Balance weight 84a Arc surface

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Toshio Kuno Fukuoka Prefecture Kasuya-gun, Sasaguri-machi Oaza, 1034-4 Kyoda Airtech Co., Ltd. (72) Inventor: Yoji Mori Inventor: Yoji Mori 1034 Wada, Sasaguri-cho, Kasuya-gun, Fukuoka Pref. (58) Field surveyed (Int.Cl. ⁶ , DB name) A62C 2/12 F24F 13/08-13/18

Claims (4)

(57) [Claims] 1. A casing provided in an air flow path, a rotating shaft rotatably provided to traverse the inside of the casing, and fixed to the rotating shaft so that air flows only in a certain flow direction. A vane provided so as to open the path and close the flow path in the reverse flow direction. The casing has a lower end when the vane rotates from the closed state to the opening direction. A backflow prevention damper comprising an arc-shaped baffle plate extending along the turning locus with a gap to the turning locus. 2. The air guide plate is formed so as to rise from the bottom wall of the casing in an arc shape, and is formed of a plate member so as to form a substantially triangular cross section with the bottom wall. Backflow prevention damper. 3. The rotating shaft is mounted at a predetermined distance from an upper wall of a casing, and a balance weight is provided on an upper end side of the blade body mounted on the rotating shaft. 3. The backflow prevention damper according to 1 or 2. 4. The wing body is mounted so as to follow a tangent on the peripheral surface of the rotating shaft, and is provided along a tangent on the downstream side in the fully closed state.
The backflow prevention damper according to any one of the above.