JP4877830B2 - Flexible duct - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible duct of high quality capable of 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, a superposed flexible linear band formed by folding the wide linear band roughly into half in the width direction with one of the side edges composed of a folded edge, is used as the flexible linear band, and the flexible linear band is caulked by the metallic linear band so that a side edge portion at an opposite side of the folded edge of the flexible linear band is positioned at an inner side of the duct with respect to the side edge portion of the folded edge side. <P>COPYRIGHT: (C)2009,JPO&amp;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. Further, when the flexible duct is desired to be used in a clean environment, there has been a problem that the loose fibers are dropped from the flexible duct and dissipated into the surrounding environment.

Further, as shown in FIG. 4, in particular, when the configuration is such that the end (cutting edge) of the side end portion of the flexible strip folded in an S shape is exposed on the outer surface of the flexible duct, the flexible strip is flexible. When handling the duct, there was a possibility that the frayed portion of the end portion on the end side of the strip would be caught and the flexible strip of the cloth material would come off from the metal strip.

In order to solve these fraying problems, a ribbon-like cloth material woven with a predetermined width so that both side ends are not frayed can be used, but 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.

In 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 the flexible strip may be detached from the metal strip. An object of the present invention is to provide a flexible duct having an excellent quality without fear of the occurrence.

As a result of intensive studies, the inventor turned the wide flexible strip into a flexible flexible strip that is folded back in the width direction so that the width is about half the width, and one side edge is formed by a folded edge. If the metal edge is caulked by the metal strip so that the side edge that is not the bent edge is inside the duct than the side edge that is the bent edge, fraying that occurs in the cut portion will occur even if a strip that cuts the cloth material is used. The inventors have found that adverse effects on the flexible duct can be prevented, and have completed the present invention.

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 strip is a superposed flexible strip formed by folding a wide strip into about a half in the width direction so that one side edge is formed by a bent edge, The flexible duct is characterized in that the side edge portion of the strip that is not the bent edge is caulked by the metal strip so that the side edge portion is located inside the duct from the side end portion of the bent edge ( Claim 1).

Further, a cloth material laminated with a resin or metal is used as a material for the superimposed flexible strip, and the laminated flexible strip is folded so that the laminate surface is exposed on the outer surface of the superimposed flexible strip. A belt may be formed (claim 2).

According to the present invention, the strip is folded in approximately half in the width direction to form a superimposed flexible strip having one side edge formed by a bent edge, and the side edge that is not the bent edge is the side edge on the side of the bent edge. Since it is located inside the duct from the part, fraying can be prevented from occurring at the side edge part composed of the bent edge, and the side edge part that is not the bent edge is the back side of the caulking structure by the metal strip Therefore, even if the cut edge is frayed, it can be prevented from being exposed to the outer surface of the duct. Accordingly, it is possible to improve the appearance of the flexible duct, prevent the flexible strip from coming off due to fraying of the cut portion, and improve the quality of the flexible duct.

Further, according to the invention of claim 2, since the superimposed flexible strip is formed by bending so that the laminate surface is exposed on the outer surface of the superimposed flexible strip, the flexible strip Even if dust or dust is generated from the cloth material that constitutes, it does not dissipate inside or outside the hose.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a partial cross-sectional view showing an embodiment of a 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. Further, in the present invention, as the flexible strip, a wide flexible strip as shown in FIG. 2 is folded back in the width direction so as to be about half the width, and one side edge portion 1d. Is formed of a bent edge, and a superposed flexible strip formed by superimposing two flexible strips on other portions is used. The overlapped portions may be bonded to each other, but may not be bonded.

As a material for the flexible strip, 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 iron plate or a thin plate of stainless steel or aluminum.

FIG. 3 shows a cross-sectional view of the caulking connection portion of the embodiment of the present invention.
On the side of the side edge 1f that is not the bent edge of the preceding wound portion 1a of the superimposed flexible strip 1 that has been wound in advance, the side end 1c is folded into a substantially S-shape, and the metal strip 2 It is caulked by a side end portion 2a that is bent toward the outside of the duct. Further, at the side end portion of the subsequent portion 1b of the flexible strip 1 that is subsequently wound around the preceding winding portion 1a, the side end portion 1e is folded substantially in an S shape on the side of the bending edge 1d. The metal strip 2 is caulked by a side end 2b that is bent toward the outside of the duct. At that time, the side edge 1f which is not the bent edge on the side of the preceding winding part 1a is arranged so as to overlap the inner side of the duct with respect to the side end part 1e of the subsequent winding part 1b. A side end 1 c and a side edge 1 f of the preceding winding portion are caulked by a side end 2 b of the metal strip 2.

In manufacturing the flexible duct of the present embodiment, first, a flexible strip (for example, aluminum laminated glass cloth) cut into a strip with a predetermined width is folded back in the width direction to about a half, and one side edge (1d) is folded. A narrow overlapping flexible strip is formed by an edge and the other side edge (1f) is formed by a cutting edge. 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 folded edge 1d side is adjacent to the cutting edge 1f of the preceding winding portion, and the metal strip 2 is supplied, and the overlapping flexible strip The side edges (1f, 1c) that are not bent edges are caulked with the metal strip 2 in advance, and then the side edges (1e) on the side of the bent edges 1d are caulked, so that adjacent side edges are caulked in a spiral shape. Connect to form a cylindrical flexible duct.

In the present embodiment, the cut cloth material is folded back in half, and one side edge of the strip is formed as a superposed strip formed by the bent edge 1d. Can be surely prevented from fraying. 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 so, it is possible to prevent a foreign object from being caught or a side edge from being torn.

Further, in the present embodiment, the strip is spirally wound and caulked so that the side edge 1f that is not the bent edge is disposed inside the duct with respect to the side end portion 1e on the bent edge 1d side. The side edge 1f in which the occurrence of sag is hidden by the cross member on the side of the bending edge 1d is hidden behind the folding structure of the caulking portion (inside the duct). Therefore, even if fraying may occur at the side edge 1f, which is a cutting edge, it is possible to prevent the fray from being exposed to the outside of the duct and detracting from aesthetics or reducing the quality of the duct. It is also possible to prevent frays from falling off and dissipating outside the duct.

In addition, when the cloth material used as the flexible strip is a cloth material laminated with a resin or metal foil, the laminate may be single-sided or double-sided. By facing the outer side of the bent portion, that is, the outer surfaces of the folded overlapping flexible strip are on the laminated side, the laminated layer covers the bent edge at the bent edge 1d. The fraying can be prevented more reliably. Furthermore, in this case, even if dust or dust may be generated from the side of the non-laminated surface of the cloth material, the dust and dust must stay between the superimposed cloth materials and dissipate to the outside. Can be prevented, so that it can be suitable for a flexible duct used in a particularly clean environment.

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 The figure which shows the structure of the overlapping flexible strip of embodiment of this invention Sectional drawing of the caulking connection part of embodiment of this invention Sectional view of the caulking connection part of a conventional flexible duct

Explanation of symbols

1 Flexible strip 2 Metal strip

Claims (2)

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;
The flexible strip is a superposed flexible strip formed by folding a wide strip into about half in the width direction so that one side edge is constituted by a bent edge,
The flexible strip is characterized by being caulked with a metal strip so that a side edge portion of the flexible strip which is not a bent edge is positioned inside the duct with respect to a side end portion on the side of the bent edge. duct. A cloth material laminated with resin or metal is used as a material for the superimposed flexible strip, and the laminated flexible strip is folded by bending so that the laminate surface is exposed on the outer surface of the superimposed flexible strip. The flexible duct according to claim 1 configured.

Images