JPS5854805Y2 - fire duct - Google Patents

Description

[Detailed explanation of the idea] This invention relates to the improvement of fire protection ducts.

With the recent increase in demand for cables, structures have been adopted in which the cables are housed within ducts.

However, if the cables are ignited or ignited for some reason, the combustion energy is enormous and may cause major secondary damage.

In particular, when a cable is installed in a vertical duct, the duct acts just like a chimney, and the danger of this increases even more, so various measures are taken to prevent the spread of fire.

As a conventional measure to prevent the spread of fire, the following methods have been implemented.

(1) Apply fire spread prevention paint to the outer circumference of the cable.

(2) Install a partition wall in the middle of the duct.

However, in the method (1) above, it is difficult to completely prevent the spread of fire in the cable, and smoke easily passes through the inside of the duct.

Also, since the cables are coated with paint, the wiring is integrated.
There is a drawback in that when the wiring is removed or added at a later date, the workability becomes extremely difficult.

In addition, in the case of method (2) above, smoke and flame can be sufficiently prevented by the partition wall, but since the inside of the duct is always open at the partition wall, ventilation inside the duct is stopped and the duct is closed. There is a problem that the temperature of the cable inside increases, and there is also the disadvantage that the workability becomes complicated when adding or removing cables at a later date.

In addition, although the above description was about cable ducts, similar problems are also raised in temperature control ducts and air conditioning ducts.

The present invention was developed as a result of extensive research in light of the current situation.The duct is open during normal times, but in the event of a fire, the cables are covered and sealed with fire-resistant and heat-resistant material. This is what I found.

That is, the present invention provides a frame made of a thermoplastic material inside the duct outer wall made of a flexible fire-resistant and heat-resistant material, and a pressing body for pressing the outer wall on the upper part of the outer wall. It is characterized by:

An example of the present invention will be explained in detail based on the drawings.

1 to 3 show the fire prevention duct of the present invention, in which FIG. 1 is a plan view, FIG. 2 is a partially peeled-off top view, and FIG. 3 is a partially peeled-off side view.

In the figure, 1 is an iron rack, 2 is a thermoplastic support made of polyvinyl chloride resin, etc., and 3 is made of a fire-resistant and heat-resistant material such as aluminum asbestos (manufactured by Kanamachi Rubber Co., Ltd.), which is made by laminating aluminum foil on asbestos cloth. 4 is a pressing object for pressing the sheet; 5 is an inverted U-shaped support arm for supporting the pressing object 4; 6 is a support arm in the rack 1; These are the installed cables.

In the present invention, the outer wall portion of the duct 1 is formed of a flexible fire-resistant and heat-resistant sheet 3, and this sheet 3 is supported from the inside by a framework of thermoplastic supports 2.

Moreover, in the present invention, a weight 4 is attached to the outside of the sheet 3 so as to press the sheet 3 at all times.

Therefore, under normal conditions, the inside of the duct 1 maintains a space, but if the inside of the duct 1 becomes abnormally high temperature due to a fire or the like, and the temperature of the space inside the duct 1 rises, the strength of the support body 2 will decrease significantly. As a result, the pressing object 4 cannot be supported at its fulcrum A and moves in the direction B due to its own weight, as shown in FIG. It becomes a type that directly covers the cables 6 and closes the inside of the duct 1.

Therefore, the spread of fire inside the duct 1 can be prevented.

Next, embodiments of the present invention will be described.

The outer wall of cable tray 1 with a width of 450 mm is approximately 1 m thick.
Covered with mt aluminum asbestos 3 and the outside of it approximately 5
A pressing device in which a kg iron pressing body 5 was supported by a support arm 4 was attached, and 20 cables 6 having an outer diameter of 35 mmφ were housed inside the duct 1.

In this case, the space inside the duct 1 has a width of 450 mm and a height of 300 mm, and the pressing devices described above are provided at intervals of about 600 mm along the longitudinal direction of the duct 1.

When the cable 6 was ignited and the internal temperature of the duct 1 reached approximately 230 to 280 DEG C., the pressing device operated as described above and was able to prevent the cable from spreading.

As detailed above, according to the fire prevention duct of the present invention, the inside of the duct has a certain amount of space under normal conditions, and once a fire occurs, the inside of the duct is closed to minimize the spread of fire to the cables stored in the duct. It has remarkable effects such as being able to limit the amount of water used.

It should be noted that the present invention can be installed only in areas that require fireproof performance.

[Brief explanation of the drawing]

Figures 1 to 3 show one example of the fire prevention duct of the present invention. Figure 1 is a plan view, Figure 2 is a partially cutaway front view, Figure 3 is a partially cutaway side view, and Figure 4 is a partially cutaway side view. The figure is an explanatory diagram of the operation of the fire prevention duct of the present invention. DESCRIPTION OF SYMBOLS 1... Rack, 2... Thermoplastic support, 3... Fire-resistant and heat-resistant sheet, 4... Pressed object, 5... Support arm, 6... Cables.

Claims (1)

[Scope of utility model registration request] The duct is characterized in that a frame made of thermoplastic material is provided inside the outer wall of the duct made of a flexible fire-resistant and heat-resistant material, and a pressing body for pressing the outer wall is provided on the upper part of the outer wall. fire duct.