JP2008062533A - Manufacturing method of heat-insulating duct hose - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a heat-insulating duct hose which can be helically wound by stabilizing the shape of a hard resin spacer when forming a space part with the help of the spacer, in the duct hose having a space part (an air layer) formed inside the hose to be used as a heat-insulating layer. <P>SOLUTION: In the process to form the air layer between the inner wall and the spacer by helically winding a hard resin strip with an internal hollow part as the spacer outside of the inner wall, a hollow helical member is formed by helically winding the strip squeezed out of an extruder beforehand, and then, transferred onto a pipe molding shaft. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a flexible duct hose having heat insulation properties.

  The flexible duct hose is piped, for example, on the ceiling of a house and used to supply the outside air supplied by the blower into the room. This is because a significant temperature difference occurs between the inside and outside of the duct hose. In order to prevent condensation on the duct surface, it is required to provide heat insulation.

As a method of imparting heat insulation properties, it is common to provide a closed cell foamed resin layer on the duct hose, but in order to further reduce the cost, a space (air layer) is formed inside the hose to insulate it. Use as a layer has been proposed (see Patent Document 1).
JP-A-11-51261

In Patent Document 1, a spiral spacer is used to form a space portion. This spacer is formed by spirally winding a belt-shaped body made of a hard resin such as hard polyethylene having a hollow portion inside. If a rigid and relatively wide strip is wound around the tube forming shaft while being linearly extruded from the extruder, the shape of the spacer tends to collapse and the shape of the predetermined space portion It has been found that it is difficult to stably hold
Then, an object of this invention is to provide the manufacturing method of the heat insulation duct hose which can be wound spirally, stabilizing the shape, when forming a space part using a spacer.

In order to solve the above problems, the present invention uses the following configuration as means.
That is, the invention of claim 1 is a process of forming an inner wall so that a flexible tape is spirally wound around a tube forming shaft and the side edges thereof are connected to each other, and the shape is retained by a spiral reinforcement, As a spacer on the outside, a step of spirally winding a hard resin strip having a hollow portion inside to form an air layer between the inner wall and the spacer, and a flexible tape outside the spacer A step of forming an outer wall by connecting the side edges of the spacer, and in the spiral winding step of the spacer, a belt-like body extruded from an extruder is spirally wound in advance to form a hollow spiral member. A method for manufacturing a heat insulation duct hose characterized in that a spiral member is transferred onto a tube forming shaft.

  The invention according to claim 2 is the method for manufacturing a heat-insulating duct hose according to claim 1, wherein the spacer has a corrugated cross-section having at least one valley along the axial direction. An air layer is formed between the valleys of the spacers.

According to the first aspect of the present invention, a hollow helix formed by spirally winding a strip of a hard resin, which is a spacer, on a tube forming shaft for the first time, instead of spirally winding to form a coil having a predetermined diameter after extrusion. Since the member is transferred onto the tube forming shaft on which the inner layer is already being formed, the spacer can be easily formed into a predetermined shape, and the air layer formed between the inner layer and the inner layer can be stably formed. Can do.
In addition to the above, the invention of claim 2 can be provided with a plurality of air layers inside and outside the spacer and can be expected to improve heat insulation, and the spacer is corrugated to ensure the flexibility of the hose. The flexibility can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a partially longitudinal side view of a duct hose formed according to the present invention. The duct hose 1 includes an inner wall 2, an air layer 4, a spacer 5 and an outer wall 6.

The inner wall 2 is formed of a soft tape wound spirally, for example, a soft resin, a resin film, a nonwoven fabric, or a composite tape of these, and adjacent side edges of the soft tape are spirally wound on the outer peripheral surface thereof. It is bonded and integrated by a spiral reinforcing body 3 made of hard resin such as polypropylene that has been rotated, and its shape retention and reinforcement are achieved.

The spacer 5 is composed of a top surface 5a and both inwardly facing upright side edges 5b and 5b, and a strip-like body made of a hard resin such as hard polyethylene having a hollow portion inside is spirally formed on the outside of the inner wall 2 The hollow part of the spacer 5 forms an air layer 4 between the inner wall 2 and heat insulation. The adjacent side edges of the spacer 5 are wound at a slight interval, but the side edges may be wound in contact with each other.

The outer wall 6 is formed by winding a soft tape, for example, a soft resin, a resin film, a non-woven fabric, or a tape obtained by combining these in a spiral manner on the outer side of the spacer 5, and a gap 7 between the adjacent spacers 5 is formed. Is also covered to prevent dew condensation in the gap 7, and the gap 7 is formed in a cavity.

  Next, an example of the manufacturing method of the heat insulation duct hose of this invention is demonstrated.

  FIG. 2 is a schematic diagram for explaining a method for manufacturing a hose. First, an inner wall forming tape is applied to a known tube forming shaft A that is supported in a cantilever state toward the lower side in the manufacturing screwing direction of the manufactured hose. 11 is continuously supplied and spirally wound, and the linear body 12 made of hard resin extruded from the extruder B is spirally wound across adjacent side edges of the tape 11. As a result, the inner wall 2 in which the spiral reinforcing body 3 is bonded and integrated is formed. In addition, in the process of screwing the inner wall 2, a cooling device C that cools the inner wall with cooling water may be provided as appropriate.

  Next, the strip 13 made of hard resin extruded from the extruder D is spirally wound around the outer periphery of the shaft core E having a predetermined diameter immediately after extrusion, and is once formed into a coil shape having a predetermined cross-sectional shape. A hollow spiral member 14 is formed. At this time, the cooling device F may be appropriately cooled by the same cooling device F as the cooling device C. Thereafter, the hollow spiral member 14 separated from the tip of the shaft core E approaches the tube forming axis A while being screwed, and moves to the outside of the inner wall 2 that rotates and advances on the tube forming shaft A, thereby forming the spacer 5. It is formed. A hollow portion between the spacer 5 and the inner wall 2 is formed as an air layer 4 for heat insulation.

  Finally, the outer wall forming tape 15 extruded from the extruder G is spirally wound around the outer side of the spacer 5, and the outer edges 6 are formed by joining the side edges to complete the molding of the duct hose 1. . The outer wall 6 is not limited to the resin tape to be extruded, and any of the above-mentioned soft tapes can be used, and these tapes can be bonded to the top surface 5a of the spacer 5. It does not have to be adhered.

FIG. 3 is a partially enlarged cross-sectional view of another duct hose formed according to the present invention. The duct hose 21 includes an inner wall 22, a spiral reinforcement 23, a first air layer 24, a spacer 25, a second air layer 26, and It consists of an outer wall 27. The duct hose 21 is different from the duct hose 1 of FIG. 1 only in the shape of the spacer, and the configuration of the other parts is the same, so the description thereof is omitted.
That is, the spacer 25 is formed in a wavy shape in cross section along the hose axis direction, and includes two peak portions 25a, 25a, a middle valley portion 25b, and both inwardly rising side edges 25c, 25c at both ends. In addition to the first air layer 24 formed between the entire spacer 25 and the inner wall 22, a second air layer 26 is formed between the valley portion 25 c and the outer wall 27.

  In addition, this invention is not limited to the said embodiment, It can change variously within the range of the summary. For example, it is sufficient that the cross-sectional shape of the spacer can be formed in a coil shape in advance, and various shapes can be arbitrarily selected. The tape material constituting the inner wall can be any flexible material that can block air from outside air. Any material can be used as long as the inner wall can be shape-reinforced as the spiral reinforcement, and in addition to a hard synthetic resin core, a metal wire such as a hard steel wire can also be used.

The partial vertical side view of the duct hose shape | molded by this invention. The schematic side view explaining the manufacturing method of this invention. The partially expanded sectional view of the other duct hose shape | molded by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Duct hose 2 Inner wall 3 Spiral reinforcement body 4 Air layer 5 Spacer 6 Outer wall 11 Inner wall formation tape 12 Linear body 13 Band-shaped body 14 Hollow spiral member 15 Outer wall formation tape 21 Duct hose 22 Inner wall 23 Spiral reinforcement body 24 First air Layer 25 Spacer 25a, 25a Mountain 25b Valley 26 Second air layer 27 Outer wall

Claims (2)

A step of forming an inner wall so that a flexible tape is spirally wound around a tube forming shaft and the side edges thereof are connected to each other, and the shape is retained by a spiral reinforcement,
As a spacer on the outer side of the inner wall, a step of spirally winding a hard resin strip having a hollow portion inside, and forming an air layer between the inner wall and the spacer,
A step of forming an outer wall by spirally winding a flexible tape on the outside of the spacer and connecting the side edges thereof;
In the spiral winding step of the spacer, a belt-like body extruded from an extruder is spirally wound in advance to form a hollow spiral member, and the hollow spiral member is transferred onto a tube forming shaft. Manufacturing method of heat insulation duct hose.   The spacer according to claim 1, wherein the spacer has a corrugated shape having at least one valley along the axial direction, and an air layer is formed between the outer wall and the valley of the spacer in the outer wall forming step. Manufacturing method of heat insulation duct hose.

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