JP2009115330A - Flexible duct - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible duct of high quality using a flexible linear band obtained by cutting a cloth material by a prescribed width, without degradation of appearance of the flexible duct caused by fray of a linear band cut portion, and possibility of separation of the flexible band from a metallic linear band. <P>SOLUTION: In this flexible duct constituted by spirally winding the flexible linear band having the prescribed width, and caulking and connecting adjacent side edge portions of the flexible linear band by the metallic linear band, at least one of the side edge portions of the flexible linear band is composed of a folded edge formed by folding the flexible linear band in the width direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a duct having flexibility. It is related with the flexible duct used especially for uses, such as ventilation.

There exists a thing as shown in patent document 1 as such a flexible duct. This document discloses a cylindrical flexible duct in which a strip of flexible cloth material is spirally wound and connected by caulking adjacent side edges with a metal strip. .
Japanese Patent Laid-Open No. 2004-270752

In these flexible ducts, the side end portion of the flexible strip of the cloth material constituting the duct wall such as glass cloth or silica cloth is folded back into an S-shape or U-shape, and the folded portion is formed into a metal strip. The side edges were connected by caulking with the folded portion of the band.

However, when using a strip obtained by cutting a cloth material into a predetermined width as these flexible strips, the following problems may occur. That is, at the side edge portion (cutting edge) of the strip obtained by cutting the cloth material, particularly when a glass cloth made of glass fiber is used as the cloth material, fibers and yarns constituting the cloth material are easily frayed. Therefore, when the flexible duct is molded with these strips, frayed fibers protrude from the caulking connection portion, and the aesthetic appearance of the flexible duct may be impaired.

In addition, as shown in FIG. 5, the flexible duct is particularly formed when the side edge portion (cutting edge) of the flexible strip folded in an S shape is exposed on the outer surface of the flexible duct. When handling, there was a possibility that the frayed portion of the side edge of the strip would get caught and the flexible strip of the cloth material would come off the metal strip.

In order to solve these fraying problems, a ribbon-like cloth material woven with a predetermined width so that the side edges do not fray can be used. However, a material that does not have such a cutting edge is expensive. It was difficult to apply to flexible ducts, because the width of the strips was determined in advance, or materials such as glass cloth were not available in the first place.

Even if a flexible strip obtained by cutting the cloth material into a predetermined width is used in the present invention, fraying of the strip stripping portion may damage the aesthetic appearance of the flexible duct, or the flexible strip may be detached from the metal strip. An object of the present invention is to provide a flexible duct with excellent quality that does not have a risk of becoming.

As a result of diligent study, the inventor folded the side end portion of the flexible strip and formed the side edge portion of the flexible strip by the bent edge. As a result, it was found that fraying generated in the cutting portion can prevent the adverse effect on the flexible duct, and the present invention has been completed.

The present invention is a flexible duct formed by spirally winding flexible strips having a predetermined width and caulking and connecting side edges of the adjacent flexible strips with metal strips. The flexible duct is characterized in that at least one side edge of the flexible strip is formed by a bent edge formed by folding the flexible strip in the width direction. (Claim 1).

In the present invention, the laminated flexible strips having a predetermined width may be spirally wound, and the side edges of the laminated flexible strips adjacent to each other may be caulked and connected by metal strips. A flexible duct, wherein at least one side edge of the laminated flexible strip constitutes the laminated flexible strip, and the flexible strip located on the outermost layer side of the duct is folded back in the width direction; A flexible duct comprising a bent edge formed so as to wrap around a side edge of another flexible strip (Claim 2).

Moreover, you may wind so that the terminal part of the folding | turning part of the said flexible strip may become inside a duct (Claim 3).

According to the present invention, at least one side edge of a flexible strip formed in a predetermined width is a flexible strip whose side edge is formed by a bent edge that is folded back in the width direction. Since the flexible duct is configured as the flexible strip that forms the duct wall, fraying can be prevented at the folded side edge, improving the aesthetic appearance of the flexible duct and fraying the cut portion. It is possible to prevent the flexible strip from coming off due to the above and to improve the quality of the flexible duct.

Further, according to the invention of claim 2, the side end portion of the outermost flexible strip is folded, the side edge portion of the other stacked strip is wrapped, and the laminated flexible strip is formed, Since the flexible duct is constituted by the strip, the same effect can be obtained at the folded side edge portion.

Furthermore, as a preferable aspect of the present invention, when the flexible strip is wound in a spiral shape so that the end portion of the folded portion is inside the flexible duct (Claim 3), fraying occurs. Exposure to the outer surface of the hose can be more effectively prevented.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a partial sectional view showing a first embodiment of the flexible duct of the present invention. In the flexible duct of the present invention, a flexible strip 1 having a predetermined width made of a flexible material is spirally wound, and adjacent side edges of the flexible strip are formed by metal strips 2. A cylindrical flexible duct is formed by continuous caulking in a spiral shape.

As a material of the flexible strip 1, an aluminum laminated glass cloth in which an aluminum foil is laminated on a glass cloth made of woven fabric of glass fibers can be used. In addition, a so-called tarpaulin fabric obtained by applying and laminating a polyethylene resin to a polyester woven fabric, or a woven cloth-like cloth material made of silica fiber or carbon fiber can be used. The fibers used for the cloth material may be natural fibers such as cotton and hemp, or may be synthetic fibers such as polyamide fibers and PET fibers. When the flexible duct is used in a high-temperature environment such as a fireproof application, it is desirable to use a cloth material made of incombustible fiber such as glass fiber or basalt fiber or flame retardant fiber. These cloth materials are used in the present invention by coating with polyethylene resin or the like for the purpose of adjusting the air permeability, applying and impregnating the resin, or laminating and evaporating a foil-like metal. be able to.

The material of the metal strip 2 can be a plated steel plate, or a thin plate of stainless steel or aluminum.

FIG. 2 shows a cross-sectional view of the caulking connection portion of the first embodiment of the present invention. The side end portion 1c of the leading wound portion 1a of the flexible strip 1 is folded in a substantially S shape, and is caulked by the side end portion 2a formed by bending the metal strip 2 toward the outside of the duct. . Further, in the side end portion 1e of the subsequent portion 1b of the flexible strip 1 that is subsequently wound around the leading winding portion 1a, the tip end portion (side edge portion) 1d of the strip side end portion is disposed inside the duct. The strip is bent toward the side, the side edge 1d of the flexible strip is formed by the bent edge, the side end portion 1e is folded substantially in an S shape, and the metal strip 2 is placed outside the duct. It is caulked by a side end 2b that is bent toward the end. At that time, the side end 1c of the preceding winding part is overlapped with the side end 1e of the subsequent winding part so as to be inside the duct, and the side end 1e of the subsequent winding part and the side of the preceding winding part The end portion of the end portion 1 c is caulked by the side end portion 2 b of the metal strip 2.

In the production of the flexible duct of the present embodiment, one side edge of the aluminum laminated glass cloth cut into a band with a predetermined width is folded back in the width direction, and one side edge is formed by a bent edge. And The obtained strip is formed into a flexible duct by a known flexible duct manufacturing method. That is, the strip is spirally wound so that the end 1f of the folded portion serving as the cutting edge is inside the duct, and the metal strip 2 is supplied so that the flexible strip is folded. The side end (1c) that has not been crimped with the metal strip 2 and then the folded back side (1e) is caulked so that the adjacent side ends are caulked together to form a cylindrical flexible duct. Form.

In the present embodiment, the side edge of the cut cloth material is folded back, and the side edge 1d of the strip is formed by the bent edge, so that it is ensured that the fibers of the cloth material are frayed from the side edge of the strip. Can be prevented. Further, by forming the side edge 1d of the strip with the bent edge, the side edge becomes smoother than when the side edge is configured with the cutting edge, and therefore the side edge is exposed to the outside of the duct. Even if it exists, it can prevent in advance that it is caught by a foreign material or a side edge tears.

Further, in the present embodiment, since the strip is spirally wound so that the end 1f of the folded portion is inside the duct, the end 1f that may be frayed is the caulked portion by the cross member itself. It is hidden behind the folding structure (inside the duct). Therefore, even if fraying may occur at the end portion 1f, it is possible to prevent fraying from being exposed to the outside of the duct and detracting from aesthetics or degrading the quality of the duct.

FIG. 3 shows a second embodiment of the present invention. In the present embodiment, at the side edges on both sides of the flexible strip, the strip is folded back in the width direction inside the duct, and the side edges 1d and 1d of the strip are formed by the bent edges. Further, the ends 1f and 1f of the folded portion are located inside the duct with respect to the side ends 1c and 1e folded in a substantially S shape, and together with the side ends 1c and 1e, the side ends 2a of the metal strip 2 2b. Further, the side edges 1d and 1d of the strip formed by the bent edges are both located on the back side (the duct inside) from the side end portions 2a and 2b of the metal strip.

In the second embodiment, by adopting such a configuration, fraying that occurs at the end portion 1f of the folded portion that is the cutting edge is exposed to the outside of the duct, detracting from aesthetics or reducing the quality of the duct. It can prevent more reliably, Furthermore, it can prevent reliably that a strip side edge is caught and a flexible strip remove | deviates from a metal strip.

Moreover, the crimping | strengthening intensity | strength can be raised by crimping the folding | returning part terminal parts 1f and 1f with the side edge parts 2a and 2b of the metal strip 2 with the side edge parts 1c and 1e.

In addition, when the cloth material used as the flexible strip is a cloth material laminated with resin or metal foil, the folded edge 1d is formed by making the laminated side face the outside of the folded portion. It is possible to more reliably prevent the occurrence of fraying.

FIG. 4 shows a third embodiment of the present invention. In the third embodiment, a laminated strip as shown below is used as the flexible strip. That is, two strips of cloth material are laminated so as to be inside / outside of the duct. At that time, the width of the cloth material 3 positioned outside the duct is made wider than the inner cloth material 4, and after laminating both, the side edge 3a of the cloth material 3 outside the duct is folded back inside the duct, The side edge 4a of the cloth material inside the duct is wrapped. Therefore, the laminated flexible strip obtained is a laminated flexible strip whose side edge portion is formed by a bent edge of the duct outer cloth material. If the laminated flexible strip obtained in this way is formed into a flexible duct by a known flexible duct manufacturing method, a caulking-connected flexible duct having a structure as shown in FIG. 4 is obtained. .

Also in the third embodiment, since the side end portion of the laminated flexible strip is formed by the bent edge, the problem of fraying that occurs at the side end cutting portion of the cloth material is the same as in the first embodiment. can be solved.

The strips to be laminated may be bonded and integrated with each other, but need not be particularly bonded. The number of sheets to be stacked may be selected as appropriate according to the specifications required for the flexible duct, but the width of the cross material strip located on the outermost layer is wider than the other strips, and the side edges of the other strips are provided. If it is folded back so that it wraps, the fraying problem that occurs at the cut edge of the strip can be similarly solved. Further, in the third embodiment, an example in which one side end portion of the laminated flexible strip is folded back is shown. However, both side end portions are folded back, and both side edges are configured by folded edges, A flexible duct having a shape similar to that of the embodiment may be used.

As described above, according to the present invention, even when a flexible strip obtained by cutting a cloth material into a predetermined width is used, fraying of the strip cutting section may damage the aesthetic appearance of the flexible duct, or may be flexible. It is possible to provide a flexible duct having excellent quality in which there is no risk that the strip will come off the metal strip.

Partial sectional view of the flexible duct of the present invention Sectional drawing of the crimping connection part of 1st Embodiment of this invention Sectional drawing of the caulking connection part of 2nd Embodiment of this invention Sectional drawing of the caulking connection part of 3rd Embodiment of this invention Sectional view of the caulking connection part of a conventional flexible duct

Explanation of symbols

1, 3, 4 Flexible strip 2 Metal strip

Claims (3)

A flexible duct formed by spirally winding a flexible strip formed in a predetermined width and caulking and connecting side edges of the flexible strips adjacent to each other by a metal strip;
A flexible duct characterized in that at least one side edge portion of the flexible strip is formed by a bent edge formed by folding the flexible strip in the width direction. A flexible duct formed by spirally winding a laminated flexible strip formed in a predetermined width and caulking and connecting side edges of the laminated flexible strip adjacent to each other by a metal strip,
At least one side edge portion of the laminated flexible strip folds the flexible strip located on the outermost layer side of the duct constituting the laminated flexible strip in the width direction, and the other flexible strip A flexible duct comprising a bent edge formed so as to wrap a side edge of a band. The flexible duct of Claim 1 or Claim 2 wound so that the terminal part of the folding | turning part of the said flexible strip might be inside a duct.

Images