JP7536684B2 - Fire damper - Google Patents

Description

The present invention relates to a fire damper that is installed at the floor slab penetration portion of a duct in an underfloor air conditioning system, which penetrates the floor slab from the lower floor and opens into the underfloor space of the upper floor.

Traditionally, to improve the comfort of workers and residents, underfloor air-conditioning systems have been used in which conditioned air is supplied to the space under a raised floor (OA floor) and blown out into the room from a floor outlet. When installing an air-conditioning duct under the floor of a given floor in this underfloor air-conditioning system, there are two possible methods: a) installing the duct in the space under the raised floor, or b) installing the duct by penetrating the floor slab from the ceiling of the floor below the given floor.

However, the above method a) has problems in that the space under the raised floor is narrow, making it impossible to install a duct large enough to supply a sufficient amount of air, and wiring for power sources and communication equipment is also installed in the raised floor space, making the space dense, which results in poor maintenance and makes it difficult to diffuse the conditioned air evenly.

On the other hand, in the case of method b) above, since the duct penetrates the floor slab, it is necessary to use fire protection equipment (hereafter referred to as a "fire damper") as stipulated in the Building Standards Act to block the inside of the duct in the event of a fire. However, compared to method a), this method has the advantage that sufficient duct space can be secured, which allows for greater freedom in installing large-diameter ducts, improves maintenance, and allows for the even diffusion of conditioned air.

For this reason, in recent years, when adopting underfloor air conditioning systems, the design has increasingly adopted method b) above. For example, Patent Document 1 proposes an underfloor air conditioning system that can penetrate a fire compartment without installing a fire damper above or below the floor slab by installing a vent device equipped with a fire damper in the floor slab.

The underfloor air conditioning system described in Patent Document 1 is equipped with a fire damper in which a pair of roughly semicircular door panels are rotatable around a support shaft. The two door panels of this fire damper are normally sandwiched between a thermal fuse in a mutually overlapping state so that they extend upward from the support shaft, and when the thermal fuse melts in the event of a fire, the two door panels rotate to shield the inside of the duct.

JP 2020-76553 A

However, in the underfloor air conditioning system described in the above-mentioned Patent Document 1, the two door panels of the fire damper are normally held overlapping each other so that they extend upward, so if the dimensions of the duct opening are about twice the thickness of the floor slab or more, the upper part of the door panel protrudes into the double floor space. Therefore, since it is necessary to limit the dimensions of the duct opening that penetrates the floor slab (fire compartment) to about twice the thickness of the floor slab or less, it becomes necessary to penetrate the floor slab with many ducts that have small opening dimensions, which creates the problem that it is difficult to improve air conditioning efficiency and cost-effectiveness.

The present invention was made to solve the above problems, and aims to provide a fire damper that allows the dimensions of the duct opening to be selected freely without being restricted by the floor slab thickness.

In order to achieve the above-mentioned object, the present invention provides a fire damper in an underfloor air-conditioning system, which is provided at the floor slab penetration portion of a duct that penetrates the floor slab from the lower floor and opens into the underfloor space of the upper floor, and is characterized by comprising a steel plate that is provided so as to be horizontally slidable between a position that opens the upper part of the floor slab penetration portion of the duct and a position that closes it, a temperature fuse that is provided to hold the steel plate in a position that opens the upper part of the floor slab penetration portion of the duct, and a biasing means that biases the steel plate in a direction that closes the upper part of the floor slab penetration portion of the duct.

The fire damper according to the present invention described above may further include a receiving member that is fitted to the inside of the upper end of the floor slab penetration portion of the duct, the steel plate is horizontally slidable relative to the receiving member, an upper standing portion is formed at one end of the steel plate, and the temperature fuse may be attached across the outer surface of the upper standing portion and the inner surface of the receiving member.

In addition, in the fire damper according to the present invention described above, a pair of rails may be provided in parallel to sandwich the floor slab penetration portion of the duct from both sides, and both sides of the steel plate may be provided so as to be slidable along the rails.

In addition, in the fire damper according to the present invention described above, protrusions that protrude outward may be formed on both sides of the steel plate.

In the fire damper according to the present invention described above, the biasing means may include a pushing mechanism that presses the central portion of the other end of the steel plate.

In the fire damper according to the present invention described above, the biasing means may include a pulling mechanism that pulls one end of each of the two sides of the steel plate toward the front.

According to the present invention, the dimensions of the duct opening can be freely selected without being restricted by the floor slab thickness, which provides a variety of excellent effects, such as improved air conditioning efficiency and cost-effectiveness.

1 is a conceptual diagram showing an example of an air conditioning system using a fire damper according to an embodiment of the present invention. FIG. 2 is a perspective view showing a normal state of the fire damper according to the first embodiment of the present invention. 1 is a plan view showing a normal state of a fire damper according to a first embodiment of the present invention; 1 is a side view showing a normal state of a fire damper according to a first embodiment of the present invention; 1 is a plan view showing a state of a fire damper according to a first embodiment of the present invention during a fire. FIG. 1 is a side view showing a state of a fire damper according to a first embodiment of the present invention during a fire. FIG. 1A and 1B are front views showing a thermal fuse of a fire damper according to a first and second embodiment of the present invention, in which FIG. 1A shows a normal state and FIG. FIG. 11 is a perspective view showing a normal state of a fire damper according to a second embodiment of the present invention. FIG. 11 is a plan view showing a normal state of a fire damper according to a second embodiment of the present invention. FIG. 6 is a side view showing a normal state of a fire damper according to a second embodiment of the present invention. FIG. 11 is a plan view showing a state of a fire damper according to a second embodiment of the present invention during a fire. FIG. 11 is a side view showing a state of a fire damper according to a second embodiment of the present invention during a fire.

Hereinafter, an embodiment of the present invention will be described with reference to the attached drawings. Note that, although terms indicating directions and positions are used in this specification, these terms are used for convenience of explanation and do not limit the technical scope of the present invention.

First, referring to FIG. 1, an air conditioning system 1 using fire dampers 10, 40 according to an embodiment of the present invention will be briefly described. FIG. 1 is a conceptual diagram showing an example of an air conditioning system 1 using fire dampers 10, 40.

As shown in FIG. 1, the air conditioning system 1 is an underfloor air conditioning system that supplies conditioned air to an underfloor space S2 of a double floor (OA floor) 2 of an indoor space S1 to be air-conditioned, and blows the conditioned air from a floor outlet 3 into the indoor space S1. The air conditioning system 1 is generally composed of an air handling unit 4 installed on the floor below the indoor space S1, a supply air (SA) duct 6 that penetrates the floor slab 5 from the air handling unit 4 and opens into the underfloor space S2, and a return air (RA) duct 8 that returns to the air handling unit 4 from a ceiling intake 7. The supply air duct 6 is a square duct, and fire dampers 10, 40 are installed at the penetration portion 6a of the supply air duct 6 into the floor slab 5.

In the air conditioning system 1 described above, the conditioned air supplied from the air handling unit 4 through the supply air duct 6 to the underfloor space S2 is supplied from the floor outlet 3 to the indoor space S1, and after conditioning the indoor space S1, it is returned to the air handling unit 4 through the ceiling intake 7 and the return air duct 8.

[First embodiment]
A fire damper 10 according to a first embodiment of the present invention will be described with reference to Figures 1 and 2 to 7. Figure 2 is a perspective view showing the fire damper 10 in a normal state, Figure 3 is a plan view showing the fire damper 10 in a normal state, Figure 4 is a side view showing the fire damper 10 in a normal state, Figure 5 is a plan view showing the fire damper 10 in a state in which a fire occurs, Figure 6 is a side view showing the fire damper 10 in a state in which a fire occurs, and Figure 7 is a front view showing a thermal fuse of the fire damper 10, where (a) shows the normal state and (b) shows the state in which a fire occurs.

The fire damper 10 according to the first embodiment of the present invention comprises a receiving member 11 attached to the upper end of the penetration portion 6a of the air supply duct 6, a steel plate 12 that is horizontally slidable relative to the receiving member 11 between a position that opens the upper part of the penetration portion 6a of the air supply duct 6 and a position that closes it, a temperature fuse 13 that is attached across the receiving member 11 and the steel plate 12 to hold the steel plate 12 in a position that opens the upper part of the penetration portion 6a of the air supply duct 6, and a push-out mechanism 14 as a biasing means that biases the steel plate 12 to a position that closes the upper part of the penetration portion 6a of the air supply duct 6.

The receiving member 11 is formed in a rectangular frame shape corresponding to the shape of the penetration part 6a of the air supply duct 6. The mounting parts 18 of the temperature fuse 13 are fixed to the center parts on both sides of the inner surface of the receiving member 11, and the mounting parts 18 have a hook shape. The receiving member 11 is fitted inside the upper end of the penetration part 6a of the air supply duct 6 so that its upper end protrudes slightly upward from the floor slab 5. By having the upper end of the receiving member 11 protrude upward from the floor slab 5 in this way, it is possible to obtain the effect of preventing unwanted objects on the floor slab 5 from falling into the inside of the air supply duct 6. In addition, this effect can be further enhanced by attaching a mesh to prevent objects from falling to the upper end of the receiving member 11.

The steel plate 12 has a thickness of 1.6 mm, and upper standing parts 15, 16 are formed vertically at one end (the left end in Figs. 3 to 6) and the other end (the right end in Figs. 3 to 6). The mounting part 17 of the temperature fuse 13 is fixed to the outer surface of the upper standing part 15 at one end above the mounting part 18 of the receiving member 11, and the mounting part 17 has a hook shape. Note that multiple temperature fuses 13 may be attached between the outer surface of the upper standing part 15 at one end and the inner surface of the receiving member 11. Also, although not shown here, one or multiple protrusions protruding outward may be formed on both sides of the steel plate 12. This reduces the width of the steel plate 12, reducing material costs, and allows the steel plate 12 to slide smoothly and reliably.

As shown clearly in FIG. 7(a), the thermal fuse 13 is formed by joining two upper and lower copper plates 20, 21 with solder 19. Circular holes 22, 23 are formed in the upper and lower copper plates 20, 21, respectively, and the thermal fuse 13 can be attached and detached to the mounting parts 17, 18 via the circular holes 22, 23. Also, as shown clearly in FIG. 7(b), when the ambient temperature of the thermal fuse 13 reaches or exceeds a predetermined temperature, the solder 19 melts and the copper plates 20, 21 separate.

A pair of rails 24, 25 are fixed in parallel on the floor slab 5 so as to sandwich the penetration portion 6a of the air supply duct 6 and the receiving member 11 from both sides. The rails 24, 25 are made of, for example, steel. Grooves 26, 27 are formed in the opposing portions of each rail 24, 25, and both sides of the steel plate 12 are formed to be slidable horizontally along the grooves 26, 27.

Stopper portions 28, 29 are formed at one end of the grooves 26, 27 of each rail 24, 25. These stopper portions 28, 29 are formed so that the upper upright portion 15 on one end side of the steel plate 12 abuts at the position where the steel plate 12 closes the upper part of the penetration portion 6a of the air supply duct 6. The other ends of each rail 24, 25 are connected to each other by a connecting member 30. The connecting member 30 is made of steel, for example, and is fixed onto the floor slab 5.

The push-out mechanism 14 is provided in a single piece so that it can be deformed from a contracted state as shown in Figs. 3 and 4 to an extended state as shown in Figs. 5 and 6, for example, by spring pressure or air pressure. The tip of the push-out mechanism 14 is fixed to the center parts on both sides of the upper standing part 16 on the other end side of the steel plate 12, and the base end of the push-out mechanism 14 is fixed to the center parts on both sides of the connecting member 30.

Note that multiple push-out mechanisms 14 may be provided. For example, push-out mechanisms 14 may be housed in the grooves 26, 27 of the rails 24, 25, respectively, and each push-out mechanism 14 may be arranged to press both sides of the upper standing portion 16 on the other end side of the steel plate 12. By installing two push-out mechanisms 14 in this way, the sliding movement of the steel plate 12 can be performed smoothly and reliably.

In the fire damper 10 according to the first embodiment having the above-mentioned configuration, as shown in FIG. 7(a), the upper and lower copper plates 20, 21 of the temperature fuse 13 fixed across the receiving member 11 and the steel plate 12 are normally held in a state of being joined by solder 19, so that, as shown in FIG. 2 to FIG. 4, the steel plate 12 opens the upper part of the penetration part 6a of the air supply duct 6 against the biasing force of the pushing mechanism 14, and is held in a constantly open state. As a result, conditioned air is supplied from the air supply duct 6 through the underfloor space S2 of the double floor 2 to the indoor space S1 from the floor outlet 3.

In the event of a fire, as shown in FIG. 7(b), the solder 19 of the temperature fuse 13 melts and the copper plates 20, 21 separate, causing the steel plate 12 to slide horizontally (to the left in the figure) along the grooves 26, 27 of the rails 24, 25 by the force of the pushing mechanism 14 to a position where it closes the upper part of the penetration part 6a of the air supply duct 6, as shown in FIG. 5 and FIG. 6. Then, the upper standing part 15 on one end side of the steel plate 12 abuts against the stopper parts 28, 29, and the state in which the steel plate 12 closes the penetration part 6a of the air supply duct 6 is maintained. This blocks the flow of conditioned air in the air supply duct 6, and a fire compartment can be formed with the floor slab 5.

According to the fire damper 10 of the first embodiment described above, the penetration portion 6a of the air supply duct 6 can be opened and closed by sliding the steel plate 12 horizontally, so the dimensions of the opening of the air supply duct 6 can be selected as desired without being restricted by the floor slab thickness. Therefore, by using an air supply duct 6 with a large opening dimension, the number of penetration points of the air supply duct 6 can be reduced, improving air conditioning efficiency and economy. In addition, workability can be improved because it is only necessary to place the fire damper 10 on the floor slab.

In addition, by using the push-out mechanism 14 as the force-applying means for the steel plate 12, the design freedom can be increased because the arrangement of the force-applying means and the number of units to be installed are less likely to be restricted by the arrangement of the penetration portion 6a of the air supply duct 6.

Second Embodiment
Next, a fire damper 40 according to a second embodiment of the present invention will be described with reference to Fig. 1 and Fig. 7 to Fig. 12. Fig. 8 is a perspective view showing the fire damper 40 in a normal state, Fig. 9 is a plan view showing the fire damper 40 in a normal state, Fig. 10 is a side view showing the fire damper 40 in a normal state, Fig. 11 is a plan view showing the fire damper 40 in a state in which a fire occurs, and Fig. 12 is a side view showing the fire damper 40 in a state in which a fire occurs. In the following description, the same components as those of the fire damper 10 according to the first embodiment are denoted by the same reference numerals in Figs. 8 to 12, and detailed description thereof will be omitted.

The fire damper 40 according to the second embodiment of the present invention includes a receiving member 11, a steel plate 41 that is horizontally slidable relative to the receiving member 11, a temperature fuse 13, and a tension mechanism 42 as a biasing means.

The steel plate 41 has a thickness of 1.6 mm, and an upper standing portion 43 is formed vertically at one end (the left end in Figs. 9 to 12). Temperature fuses 13 are fixed at corresponding positions on the upper and lower sides of the outer surface of the upper standing portion 43 and the central portion on both sides of the inner surface of the receiving member 11 via mounting portions 17 and 18. Protrusions 44 and 45 that protrude outward are formed on both sides of the steel plate 41. The number of protrusions 44 and 45 may be one each, but by providing two or more each as shown in Figs. 9 and 11, the width of the steel plate 41 can be reduced, reducing material costs, and the sliding movement of the steel plate 41 can be performed smoothly and reliably. The other end of the steel plate 41 (the right end in Figs. 9 to 12) does not have an upper standing portion formed, unlike the steel plate 12 of the first embodiment described above.

A pair of rails 46, 47 are fixed in parallel on the floor slab 5 so as to sandwich the penetration portion 6a of the air supply duct 6 and the receiving member 11 from both sides, and the rails 46, 47 are made of, for example, steel. Grooves 48, 49 are formed in the mutually facing portions of each rail 46, 47, and the protrusions 44, 45 on both sides of the steel plate 41 are formed so as to be able to slide horizontally along the grooves 48, 49. In addition, stopper portions 50, 51 are respectively provided on the mutually facing portions of each rail 46, 47 on one end side of the receiving member 11, protruding in a direction approaching each other.

The ends of each rail 46, 47 are connected to each other by connecting members 52, 53, respectively. The connecting members 52, 53 are made of, for example, steel and are fixed onto the floor slab 5.

The tension mechanism 42 includes, for example, tension coil springs 54, which are housed in the grooves 48, 49 of the rails 46, 47, respectively. One end of each tension coil spring 54 is supported on the side of the connecting member 52 via a mounting bracket 55, and the other end of each tension coil spring 54 is supported on the outer surface of the upper rising portion 43 of the steel plate 41 via a mounting bracket 56. This allows the tension mechanism 42 to be deformed from an extended state as shown in Figures 9 and 10 to a contracted state as shown in Figures 11 and 12. The tension coil springs 54 may be housed in, for example, a steel cylinder, which can improve the fire resistance of the tension mechanism 42.

In the fire damper 40 according to the second embodiment having the above-mentioned configuration, the temperature fuse 13 is normally kept connected, so that the steel plate 41 opens the upper part of the penetration part 6a of the air supply duct 6 against the biasing force of the tension coil spring 54, as shown in Figures 8 to 10, and is always kept in an open state. As a result, conditioned air is supplied from the air supply duct 6 through the underfloor space S2 of the double floor 2 to the indoor space S1 from the floor outlet 3.

Meanwhile, in the event of a fire, when the temperature fuse 13 melts, the steel plate 41 of the fire damper 40 slides horizontally (to the left in the figure) along the grooves 48, 49 of the rails 46, 47 due to the biasing force of the tension mechanism 42 until it closes the upper part of the penetration part 6a of the air supply duct 6, as shown in Figures 11 and 12. Then, the upper upright part 43 of the steel plate 41 abuts against the stopper parts 50, 51, and the state in which the steel plate 12 closes the penetration part 6a of the air supply duct 6 is maintained. This blocks the flow of conditioned air through the air supply duct 6, and a fire compartment can be formed with the floor slab 5.

According to the fire damper 40 of the second embodiment described above, the steel plate 41 can slide horizontally to open and close the penetration portion 6a of the air supply duct 6, so the dimensions of the opening of the air supply duct 6 can be selected as desired without being restricted by the floor slab thickness. Therefore, by using an air supply duct 6 with a large opening dimension, the number of penetration points of the air supply duct 6 can be reduced, improving air conditioning efficiency and economy. In addition, workability can be improved because it is only necessary to place the fire damper 40 on the floor slab.

In addition, by accommodating the tension mechanism 42, which is used as a means for biasing the steel plate 12, in the grooves 48, 49 of the rails 46, 47, the steel plate 41, tension mechanism 42, and rails 46, 47, etc., can be easily unitized, improving workability and cost-effectiveness.

In the fire dampers 10 and 40 according to the first and second embodiments described above, the upper end of the receiving member 11 protrudes slightly upward from the floor slab 5, but the upper end of the receiving member 11 may be at the same height as the floor slab 5. This allows the height of the underfloor space S2 of the double floor 2 to be kept lower and allows the underfloor space S2 to be used more effectively.

In addition, without installing the receiving member 11, the temperature fuse 13 may be attached across the outer surface of the upper upright portion 15, 43 on one end side of the steel plates 12, 41 and the inner surface of the penetration portion 6a of the air supply duct 6. In this case, in the event of a fire, the steel plates 12, 41 directly close the upper end of the penetration portion 6a of the air supply duct 6.

In addition, in the first and second embodiments described above, the air supply duct 6 is a square duct, but the air supply duct may be a round duct.

The above description of the embodiment of the present invention describes a preferred embodiment of the fire damper according to the present invention, and therefore may include various technically preferable limitations, but the technical scope of the present invention is not limited to these aspects unless otherwise specified to limit the present invention.

REFERENCE SIGNS LIST 1 Air conditioning system 5 Floor slab 6 Air supply duct 6a Penetration portion 10 Fire damper 11 Receiving member 12 Steel plate 13 Temperature fuse 14 Push-out mechanism (biasing means)
15 Upper standing portion 24 Rail 25 Rail 26 Groove portion 27 Groove portion 40 Fire damper 41 Steel plate 42 Pulling mechanism (biasing means)
43 Upper standing portion 44 Protrusion 45 Protrusion 46 Rail 47 Rail 48 Groove portion 49 Groove portion

Claims (5)

A fire damper installed at a floor slab penetration portion of a duct that penetrates the floor slab from a lower floor and opens into an underfloor space of an upper floor in an underfloor air-conditioning system,
A steel plate that is horizontally slidable between a position that opens and a position that closes the upper portion of the floor slab penetration portion of the duct;
A thermal fuse is provided to hold the steel plate in a position that opens an upper portion of the floor slab penetration portion of the duct;
A biasing means for biasing the steel plate in a direction to close an upper portion of the floor slab penetration portion of the duct;
A receiving member that is provided so as to be engageable with the inside of an upper end portion of the floor slab penetrating portion of the duct;
the steel plate is arranged so as to be horizontally slidable relative to the receiving member, an upwardly raised portion is formed at one end of the steel plate, and the temperature fuse is attached across an outer surface of the upwardly raised portion and an inner surface of the receiving member . A fire damper as described in claim 1, characterized in that a pair of rails are arranged parallel to each other to sandwich the floor slab penetration portion of the duct on both sides, and both sides of the steel plate are arranged to be slidable along the rails. 3. The fire damper according to claim 2 , wherein protrusions protruding outward are formed on both sides of the steel plate. 4. The fire damper according to claim 1, wherein the biasing means includes a pushing mechanism for pushing the central portion of the other end of the steel plate. 4. The fire damper according to claim 1 , wherein the biasing means includes a tension mechanism for pulling one end of each of the steel plates toward the front.

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