JPH0216770Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] This invention relates to a fire damper that is attached to a house and automatically closes in the event of a fire.

[Background technology]

Ventilation holes for ventilation in the attic space need to be closed in the event of a fire, as it may cause a chimney effect. For this reason, fire dampers need to be installed in the attic ventilation holes of houses in semi-fire protection areas. Conventionally, various types of fire dampers have been used that automatically close in the event of a fire and block the chimney effect, but all of them have complex structures.

[Purpose of invention]

The purpose of this invention is to provide a fire damper with a simple structure.

[Disclosure of invention]

In order to achieve the above-mentioned purpose, this invention is a fire prevention damper that is attached to an attic ventilation hole provided in the eaves, and includes an on-off valve that opens and closes the ventilation hole, and an on-off valve that biases the on-off valve in the opening direction. A spring-like shape memory alloy body that biases the opening/closing valve in the closing direction against the biasing force of the spring and a shape memory alloy body that biases the valve in the closing direction against the biasing force of the spring. When the body is deformed and the on-off valve is held in the open state, and when the temperature exceeds a predetermined temperature, the shape memory alloy body resists the biasing force of the spring and returns to its memorized shape, thereby keeping the on-off valve in the closed state. Its gist is a fire damper that is characterized by the fact that it is Hereinafter, this invention will be explained in detail based on drawings showing embodiments.

1 and 2 show a fire damper according to this invention. As shown in the figure, this fire damper consists of a ventilation hole 1 provided in a house, a horizontal piece 2 extending from one side to the other side, and a hole 2 provided in the horizontal piece 2.
The ventilation hole 1 is provided with a rod 3 that is passed through the hole 3a, and an on-off valve 4 that is fixed to one end of the rod 3 and opens and closes the ventilation hole 1. The rod body 3 has a retaining portion 3a that prevents it from coming off from the hole 2a at the end opposite to the on-off valve 4. A coil spring 5 is inserted between the horizontal piece 2 of the rod body 3 and the on-off valve 4, and a coiled shape memory alloy body 6 is inserted between the horizontal piece 2 of the rod body 3 and the retaining part 3a. has been inserted. The coil spring 5 urges the on-off valve 4 in a direction away from the horizontal piece 2. That is, the open state of the on-off valve 4 is maintained by the force of the coil spring 5. Shape memory alloys remember their shape if they are given a shape and then heat treated, and can be deformed into various shapes below a certain temperature (transformation temperature), but when heated to that temperature, they always instantly return to their original shape. It has the property of returning to its shape. Shape memory alloys include nickel-titanium, copper-zinc-aluminum, and copper-
Examples include alloys such as cadmium, copper-zinc, and nickel-aluminum. In this embodiment, the shape memory alloy body 6 memorizes the coil shape in an extended state as shown in FIG. 2, and exerts a biasing force greater than that of the spring 5 at temperatures above the transformation temperature. However, below the transformation temperature, only a smaller biasing force can be exerted than that of spring 5, and as shown in Fig. 1, the shape is deformed by the biasing force of spring 5 and shortened. It is becoming a state.

This fire damper operates as follows. Normally, as shown in FIG. 1, the shape memory alloy body 6 is in a contracted state, so the on-off valve 4 is held open by the force of the coil spring 5, preventing air from entering and exiting. unhindered. In the event of a fire, when the shape memory alloy body 6 is heated and reaches a transformation temperature, the shape memory alloy body 6 stretches and returns to its memorized shape, as shown in FIG. Due to the force of the shape memory alloy body 6 returning to its memorized shape, the coil spring 5
The on-off valve 4 is closed against this. In this way, air inflow and outflow through the ventilation hole 1 is blocked, and it is possible to prevent a fire from starting in the attic.

Note that after the on-off valve 4 is closed, if the fire is extinguished and the temperature of the shape memory alloy body 6 returns to below the transformation temperature, the shape memory alloy body 6 will be easily deformed again and the biasing force will be reduced. becomes smaller, so of course
Needless to say, the on-off valve 4 opens due to the biasing force of the spring 5, returning to the state shown in FIG.

The temperature at which the shape memory alloy body 6 returns to its memorized shape (transformation temperature of the alloy) is preferably about 80°C. This is because the atmospheric temperature inside the attic rises to about 40 to 70 degrees Celsius in the summer, so if the transformation temperature is set to 80 degrees Celsius or lower, there is a high risk that the on-off valve will close even when there is no fire. The transformation temperature of a shape memory alloy can be adjusted by changing the alloy composition and heat treatment conditions. The on-off valve is preferably made of inorganic material and is nonflammable.

An example of the installation of the fire damper is shown in FIG. As shown in the figure, a fire damper 9 is shown installed in a ventilation hole 8 for attic ventilation provided in the eaves 7 of the eaves.

[Effect of idea]

Since the fire damper according to this invention has the above-mentioned configuration, it has a very simple structure.

In other words, the operating mechanism of the on-off valve is only equipped with a spring and a shape memory alloy body, and there are no mechanically complex structural parts, which greatly reduces the number of parts and the bulk of the entire operating mechanism. It is lower and more compact, making it easier to manufacture and assemble the entire fire damper, which can greatly contribute to cost reduction. In addition, the on-off valve operates based on the difference in the biasing force between the spring and the shape memory alloy body above and below the transformation temperature, so it operates reliably and has almost no possibility of malfunction or malfunction, and is highly durable. becomes.

Since the biasing force of the shape memory alloy body increases and decreases reversibly as the temperature rises and falls, an operation confirmation test can be easily performed. In other words, if the shape memory alloy body is heated to a temperature higher than the transformation temperature by blowing hot air or bringing a heat source close to the on-off valve, the on-off valve will close due to the biasing force of the shape memory alloy body, and a fire will occur. It can be confirmed that the fire damper operates reliably during the event. After operation is confirmed, if the heat is removed, the shape memory alloy body will be cooled below its transformation temperature, the biasing force of the shape memory alloy body will become smaller, and the biasing force of the spring will become larger, so the on-off valve will automatically open and close. The opening direction is automatically operated and the opening state is maintained. In this way, after the operation confirmation test, the fire damper will return to its original state without any operations, so it is not necessary to perform complicated operations or install new parts to return the fire damper to its original state. There is no need to make any repairs, and operation confirmation tests can be performed extremely easily and reliably.

In addition, the on-off valve will automatically return to the open state not only after the operation confirmation test, but also after a fire is extinguished or after the on-off valve malfunctions due to exposure to high heat due to a cause other than a fire. Become. Therefore, the problem of forgetting to reset the on-off valve and its operating mechanism after an operation confirmation test, resulting in the ventilation hole remaining closed and causing an accident such as poor ventilation, does not occur, and the fire damper It can greatly contribute to improving reliability and safety as well as ease of handling.

[Brief explanation of drawings]

Figures 1 and 2 are partial cross-sectional side views showing the fire damper according to this invention installed in a ventilation hole, and Figure 3 shows the fire damper installed in a ventilation hole in the eaves. It is a diagram. 4...Opening/closing valve, 5...Spring, 6...Shape memory alloy body, 9...Fire damper.

Claims (1)

[Scope of utility model registration request] A fire damper installed in an attic ventilation hole installed in the eaves, which includes an on-off valve that opens and closes the ventilation hole, a spring that biases the on-off valve in the opening direction and holds it in the open state, and a biasing force of the spring. It is equipped with a spring-like shape memory alloy body that biases the on-off valve in the closing direction in opposition to the temperature, and when the temperature is below a predetermined temperature, the shape memory alloy body is deformed by the biasing force of the spring and the on-off valve is held in the open state. , a fire prevention damper characterized in that when the temperature exceeds a predetermined temperature, the shape memory alloy body resists the biasing force of a spring and returns to its memorized shape, thereby holding the opening/closing valve in a closed state. .