JPH06101902A - Sound deadening duct - Google Patents

Abstract

PURPOSE:To provide a sound deadening duct with a simplified structure and demonstrating a remarkable sound deadening effect. CONSTITUTION:A sound deadening duct 1 comprises a duct body constituted with punching metal with a 25% opening rate and including an entire wall surface made a porous sound transparent wall 11, and an airtight sheet 20 laminated on the porous sound transparent wall 11 so as to sealing the same in an airtight manner. The airtight sheet 20 is of an incombustible sound transparent one yielded by molding inorganic fibers for example with a phenol binder in a mat configuration, and covering it with an inorganic cross. Hereby, any noise in the sound deadening duct 1 passes through the porous sound transparent wall 11 and the airtight sheet 20 and is actively discharged to the outside of the duct 1, whereby the sound deadening duct 1 reduces the sound to the utmost and fan air is prevented by the airtight sheet 20 from being discharged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a duct used for an air conditioner, a smoke exhaust device and the like, and more particularly to a noise reduction duct for reducing the noise as much as possible.

[0002]

2. Description of the Related Art Instead of a structure in which a sound absorbing material such as glass wool, which cannot be expected to muffle low-frequency noise, is laminated on a duct body, for example, JP-A-1-296040, JP-A-1-302060, etc. Are known.

According to these, a partition wall having a predetermined structure is provided in the duct, and the noise is to be reduced by forcibly converting the noise into heat energy in the duct. .

[0004]

However, in this case, since it is necessary to additionally arrange a partition wall having a predetermined structure in the tubular duct, the duct, especially the internal structure, becomes complicated, The problem remains that production becomes complicated.

The present invention has been made in view of the above problems of the muffling duct, and the problem to be solved is to provide a muffling duct having a simple structure and a remarkable noise reduction effect regardless of the frequency. It is in.

[0006]

While this type of conventional duct has the technical idea of treating noise inside the duct, the present invention is characterized by positively emitting noise to the ceiling and the like. It has a basic technical idea in terms of reducing noise. Therefore, make the aperture ratio 20% or more,
A punching metal that enables noise emission partitions the wall surface of the duct main body to make it a porous sound-transmitting wall, while the emission of blast air is hermetically sealed to the porous sound-transmitting wall. A sheet is used to prevent this, and at the same time both the function of reducing noise and the function of blowing air are secured, and the aperture ratio of the punching metal is 40%.
% Or less to secure the strength of the porous sound-transmitting wall, and to form one or all wall surfaces of the duct body by the punching metal so as to form the shape-retaining structural element of the duct body itself. That is, the present invention relates to a duct main body in which 1 to all wall surfaces are partitioned by perforated sound-permeable walls of punching metal having an opening ratio of 20% or more,
A sound deadening duct comprising: a non-combustible sound-permeable airtight sheet laminated on the porous sound-permeable wall so as to hermetically seal the porous sound-permeable wall of the duct body (claim 1); The aperture ratio of the punching metal is regulated to 40% or less so that the porous sound-transmitting wall according to claim 1 is used as a duct main body shape retention structural element, and the whole wall surface of the duct main body is formed by the punching metal, or one or a plurality thereof. A sound deadening duct characterized by forming a wall surface (Claim 2), and a reinforcing joint flange for reinforcing the shape retention of the duct main body is additionally provided at the open end of the duct main body according to Claim 1 or 2. A sound-deadening duct (claim 3) and the airtight sheet according to any one of claims 1 to 3, wherein the inorganic fiber is molded into a mat with a binder, or the surface of which is laminated with an inorganic cloth. Be Te is obtained by the means of the problem solution as the gist of the dependency and invention these respective muffler ducts (claim 4), characterized in.

In the present invention, when the wall surface is formed by using the porous sound-transmitting wall as a shape-retaining structural element in the partition of the wall surface by the porous sound-transmitting wall, and the shape retention of the duct main body is, for example, a shape-retaining frame. It is used to mean the case where the wall surface is simply divided to form the base of the airtight sheet depending on the above.

[0008]

According to the present invention, when noise from an air conditioner or the like passes through the sound-deadening duct, it passes through the through hole of the duct body and the airtight sheet of incombustible sound-transmitting, and is discharged to the outside of the duct such as the ceiling. Air blown by the machine is prevented from being discharged to the outside of the duct by the airtight sheet, and is guided to a predetermined outlet such as an outlet.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the drawings showing the following embodiments. 1 is a straight line type muffler, 2 is a curved elbow, and each muffling duct is a muffling duct. The main body 10 and the airtight sheet 20 that surrounds the main body 10 are provided, and are configured as a rectangular tubular section.

The duct body 10 is constructed by partitioning the entire wall surface with a perforated sound-transmitting wall 11 made of punching metal having an opening ratio of 25%. In this example, the perforated sound-transmitting wall 11 retains the shape of the duct body 10. All the wall surfaces of the duct body 10 are formed as structural elements.

That is, the duct body 10 of the present embodiment is constructed by punching a 0.6 mm zinc iron plate and welding the punching metal having an opening ratio of 25% so as to form the sound deadening ducts 1 and 2. By this, the entire wall surface is used as the perforated sound-transmitting wall 11 and the shape-retaining structural element is used to secure the shape-retaining property of the duct body 10.

As described above, the duct main body 10 itself has shape-retaining property, but in the present example, the shape-retaining property of the duct main body 10 is further reinforced so that the duct main body 10 has resistance to external force in the construction work. In order to secure it, a reinforcing joint flange 13 integrally formed with a thick steel plate is welded to the opening ends before and after the air blowing direction, and the reinforcing joint flange 13 is arranged to project at the opening end.

On the other hand, the airtight sheet 20 is formed by molding inorganic fibers into a mat with a binder and laminating and covering the surface thereof with inorganic cloth. In this example, this airtight sheet is made of glass fiber 90 wt% after firing.
%, Phenol resin 5 wt%, silica 1 wt% as a main component of long glass fiber and niddle punching, and silica-added phenol resin as an impregnated binder, for example, 6 mm The surface of a glass fiber mat 21 compression-molded into a thick mat is laminated with a glass cloth 22 bonded with an aluminum foil of 20 μm, whereby the airtight sheet 20 is nonflammable and partially absorbs noise. However, it has a sound-transmitting property that allows noise to pass through, and at the same time has an airtight property.

The airtight sheet 20 is the duct body 1 described above.
0 is surrounded by a circular shape, and the porous sound-transmitting walls 11 of the duct body 10 are laminated and arranged so as to hermetically seal. In this laminated arrangement, the airtight sheet 20 is adhered and fixed to each porous sound-permeable wall 11 on the outer peripheral side in this example in a pressure-covered manner, and the metal fitting 23 is fixed at an appropriate place, and the end portion of the airtight sheet 20 is The airtight sheet 20 is adhered to the perforated sound-transmitting wall 11 of the duct main body 10 in one piece by adhesion by an aluminum tape (not shown).

With this configuration, the muffler ducts 1 and 2 positively discharge the noise generated by the air conditioner or the like when the air is blown to the outside of the duct without treating it inside the duct to reduce the noise as much as possible. While this is prevented from propagating to the air outlet and the like, the blowing air is prevented from being discharged and the blowing guidance of the air is effectively performed. Further, this sound-deadening duct includes a punching metal duct body 10 and a non-flammable and sound-permeable airtight sheet 2.
Since it is composed of 0, it has a non-flammability as a whole and also has a heat insulating property due to the airtight sheet 20.

In the figure, reference numeral 12 is a fold-back welding allowance of the porous sound-transmitting wall 11 in the duct body 10, and 14 is a joint flange 1.
3 is a bolt hole, 15 is a connecting bolt nut, and 24 is a seal portion in the metal fitting 23 portion of the airtight sheet 20.

Although the illustrated example is as described above, in carrying out the present invention, a perforated sound-transmitting wall of punching metal is necessary, for example, so as to partition the three surfaces of the upper surface and the side surface avoiding the ceiling back surface side. According to the above, it can be used for one or more surfaces of the duct body, and the other surface can be configured to be, for example, a flat metal panel.

The wall surface section by the porous sound-transmitting wall is, for example, 0.
A thin punching metal with a thickness of 1 mm to 0.2 mm is used, and this is stretched on, for example, an inner or outer shape-maintaining frame that secures the structural strength of the duct body. You may make it.

On the other hand, when a porous sound-transmitting wall is used as a shape-retaining structural element on a plurality of surfaces including one to all surfaces of the duct body to form the wall surface, in general, one side of the duct body is 30 cm. , It is effective to use a punching metal with a thickness of 0.5 mm or more, and it is generally necessary that the aperture ratio of the punching metal be 40% or less in order to form the shape-retaining structural element. Is 40% or less, particularly preferably 30% or less.

If the aperture ratio of the punching metal is less than 20%, it becomes difficult to effectively emit noise.
The aperture ratio is set to 20% or more, but the upper limit of the aperture ratio may be set to 40% or less when the shape-retaining structural element is used and may be set to an appropriately determined ratio when the shape-retaining structural element is not used.

The airtight sheet is formed by molding the above-mentioned inorganic fiber into a mat with a binder. It is effective in improving the productivity of the sound deadening duct by simplifying the stacking arrangement on the duct body, but it is airtight. Since the sheet may have both noncombustibility and sound permeability, for example, the one in which a bag-like sheet is filled with inorganic fibers in a compressed form, the one in which a metal such as aluminum is vapor-deposited on a thick glass cloth is appropriately used. This can be selected and used.

The noise emitted outside the duct by the muffler duct of the present invention generally disappears as thermal energy in a space such as the ceiling, but when the space is small, it may reach the muffler duct again. If the aperture ratio of the punching metal is set to 25%, it is confirmed that the punching metal hardly re-enters the muffling duct.
When the space is narrow, it is particularly effective to set the aperture ratio to a relatively small value, for example, 30% or less.

In carrying out the present invention including the above, each specific material, shape, structure, size, of the porous sound-permeable wall of punching metal, the opening ratio, the duct body, and the non-combustible sound-permeable airtight sheet,
These relationships and additions thereto can be variously modified without departing from the spirit of the invention, and are not limited to those shown or described above.

[0024]

As described above, the present invention has an aperture ratio of 20%.
A duct main body whose one or all wall surfaces are partitioned by the above-mentioned perforated sound-permeable wall of punching metal, and a non-combustible transparent material which is laminated on the perforated sound-permeable wall so as to hermetically seal the perforated sound-permeable wall of the duct main body. Since it is characterized by comprising a sound-tight sheet, it is possible to provide a muffling duct having a remarkable noise reduction effect by positively emitting noise outside the duct regardless of the frequency level. Further, since the sound deadening duct of the present invention only needs to have the perforated sound-permeable wall of punching metal and the non-combustible sound-permeable airtight sheet, it has the above-mentioned noise reduction effect, while the structure can be simplified. Eliminate the complexity of production.

According to a second aspect of the present invention, the opening ratio of the punching metal is restricted to 40% or less so that the perforated sound-transmitting wall serves as a duct body shape retention structural element, and the entire wall surface of the duct body is formed by the punching metal. Alternatively, since one or more wall surfaces thereof are formed, in addition to the above, the structure of the sound deadening duct can be simplified by using the porous sound-transmitting wall as a shape-retaining structural element of the duct body.

According to a third aspect of the present invention, a reinforcing joint flange for reinforcing the shape retention of the duct body is additionally provided at the open end of the duct body so as to project. The flange can also be used as a joint to reinforce the shape retention of the duct body, and as a sound deadening duct with superior shape retention, it is possible to prevent deformation due to external force during duct construction.

According to a fourth aspect of the present invention, the airtight sheet is an airtight sheet formed by molding inorganic fibers into a mat with a binder or laminating the surface thereof with an inorganic cloth. Further, while effectively ensuring the non-combustible sound-transmitting property and the airtightness, the laminated coating can be easily performed, and the sound deadening duct having a good productivity can be obtained.

[Brief description of drawings]

Fig. 1 Perspective view of the muffler duct Fig. 2 Front view showing the structure of the muffler duct with the airtight sheet partially cut away. Fig. 3 Partially enlarged vertical sectional view of the airtight sheet.

[Explanation of symbols]

 1 sound deadening duct 2 sound deadening duct 10 duct body 11 porous sound-permeable wall 13 joint flange 20 airtight sheet

Claims (4)

[Claims] 1. A duct body having one or all wall surfaces partitioned by a perforated sound-permeable wall of punching metal having an opening ratio of 20% or more, and the porous body of the duct body so as to hermetically seal the sound-permeable wall. A sound deadening duct comprising: a non-combustible sound-permeable airtight sheet laminated on a sound-permeable wall. 2. The aperture ratio of the punching metal is set to 4 so that the perforated sound-transmitting wall of claim 1 is used as a duct body shape retention structural element.
A sound deadening duct characterized in that the entire wall surface of the duct body is formed by the punching metal while being regulated to 0% or less, or one or more wall surfaces thereof are formed. 3. A sound deadening duct characterized in that a reinforcing joint flange for reinforcing the shape retention of the duct main body is additionally extended at the open end of the duct main body according to claim 1 or 2. 4. A sound deadening duct, characterized in that the airtight sheet according to any one of claims 1 to 3 is formed as an airtight sheet by molding inorganic fibers into a mat with a binder or laminating and covering an inorganic cloth on the surface thereof.