JP4815365B2 - Flat oval flexible duct, manufacturing method and molding method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat oval type flexible duct having a flat face though it is long. <P>SOLUTION: A pair of large diameter-press members 11 having circular arc-shaped outer peripheral faces are vertically disposed at a prescribed distance, a pair of small diameter-press members 12 having circular arc-shaped outer peripheral faces of a diameter smaller than that of the large diameter-press members 11 are disposed between the pair of large diameter-press members at a distance right and left, and round pipe-type flexible ducts 101 are respectively inserted from one end side of the pair of small diameter-press members 12. The round pipe-type flexible ducts 101 are deformed in such a state that the round pipe-type flexible ducts 101 are vertically held so that the large diameter-press members 11 and the small diameter-press members 12 are linearly kept into contact with each other. A core material 2 compressed after demolding, is sprung back to constitute the flat oval-type flexible duct 1 having the cross-sectional shape composed of two linear parts extending in parallel with the long diameter direction and a circular arc-shaped part. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

The present invention is a flat oval flexible duct, to a process for their preparation and molding how.

  Conventionally, an axially flexible flexible duct formed by alternately winding a core material for holding a shape and a belt-like sheet material (film material) in a spiral shape is known (for example, a patent Reference 1).

  Such a flexible duct is generally used to circulate a fluid in an air conditioner or the like. In particular, when such a flexible duct is arranged in the ceiling space, space saving and air volume can be ensured by arranging a small vertical space with a low vertical height and a large cross-sectional area.

  Therefore, for example, as in Patent Document 2, a flexible duct having an elliptical cross-sectional shape is known. This flexible duct is composed of a galvanized steel wire and a glass cloth wound in a spiral shape. An elliptical mold is inserted into a circular flexible duct and deformed by applying internal pressure. By forming the flat oval mold in this way, it is possible to obtain a flexible duct with good flexibility and low pressure loss while effectively using space.

  In addition, as a technique for forming a round tube into a cross-section oval type, for example, as disclosed in Patent Document 3, a steel pipe is placed in a multistage forming roller and is deformed into a cross-section oval type.

In addition, as disclosed in Patent Document 4, as a method of forming an annular cross-section tubular body into a flat oval shape, a method is known in which a mold is pushed inward in the left-right direction in conjunction with a mold that crushes the pipe up and down. It has been.
JP-A-8-014490 Japanese Patent Laid-Open No. 9-280637 JP 2000-015328 A Japanese Patent Application Laid-Open No. 60-127022

  By the way, when a bending process is applied to the metal material, the bending deformation of the metal material is somewhat restored due to elasticity after the process. This phenomenon is called springback. Considering the influence of such a spring back, if it is a method of forming by applying pressure only from the inside as in Patent Document 2, if a material having a large spring back is to be formed, a flat portion will be formed after forming. Will spring back and swell, and flat parts cannot be molded. In this method, a mechanism for expanding the mold is provided on one end side of the mold, and a flexible duct before molding must be inserted from the other end side, so that the mold is in a cantilever state. When the duct diameter is small, there is a problem that it is difficult to secure the rigidity of the mold because the diameter of the mold inserted into the duct is small, and a long flexible duct cannot be formed.

  In the above-mentioned patent document 3, the rigidity of the flexible duct itself in which the core material is spirally wound is low, and when a force is applied in the vertical direction when it is put into the roller, it is uniformly deformed like a round tube. Therefore, the spiral core material escapes so as to fall in the axial direction and cannot be molded.

  Moreover, in the thing of the said patent document 4, there existed a problem that the linear part of the boundary of the part which has an arc-shaped outer peripheral surface, and a flat part did not fully plastically deform, and cannot shape | mold to a flat oval type | mold.

  This invention is made | formed in view of this point, The place made into the objective is to obtain the flat oval type flexible duct which has a flat surface even if it is long.

  In order to achieve the above object, according to the present invention, the straight portion of the boundary between the arc-shaped outer peripheral surface and the flat outer peripheral surface is pressed and reliably plastically deformed.

  Specifically, in the first invention, a core material and a sheet material for maintaining the shape are provided, and two linear portions and a circle that are extendable in the axial direction and whose cross-sectional shape extends parallel to the major axis direction. The present invention is directed to a method of manufacturing a flat oval flexible duct composed of an arcuate portion.

And the manufacturing method of this flat oval type flexible duct is:
A preforming step of forming a circular tube-shaped flexible duct having a circular cross-sectional shape formed by alternately winding the core material and the belt-shaped sheet material in a spiral shape;
A pair of large-diameter press members having an arcuate outer peripheral surface are arranged at a predetermined distance above and below, and a pair of arc-shaped outer peripheral surfaces having a smaller diameter than the large-diameter press member is disposed between the pair of large-diameter press members. A mounting step in which the small-diameter press member is arranged at a distance from side to side, and the round tube type flexible duct is inserted from one end side of the pair of small-diameter press members,
While holding the round tube type flexible duct from above and below so that the large-diameter press member and the small-diameter press member are in line contact with each other while bringing the large-diameter press member close to each other and separating the small-diameter press member from each other A pressing step for deforming the round tube type flexible duct;
The large-diameter press members are separated from each other, and a demolding step of demolding the small-diameter press members close to each other is performed.

  According to the above configuration, since the small-diameter press member is disposed inside the round tube type flexible duct, the insertion side cantilever is free unless a mechanism for supporting the insertion side is provided after the round tube type flexible duct is inserted. It becomes a state. However, since the large-diameter press member does not need to insert a round tube type flexible duct from one end side unlike the small-diameter press member, both ends can be supported and rigidity is ensured. For this reason, even if it is a long and small-diameter round tube flexible duct, not only the cantilevered small-diameter press member, but also the round tube-type flexible duct is sandwiched from above and below with the large-diameter press member supported at both ends. The linear portion extending in the axial direction that becomes the boundary between the arc-shaped outer peripheral surface and the flat outer peripheral surface of the flat oval flexible duct held between them is surely pressed and plastically deformed. Therefore, even if a springback occurs in the elastically deformed part after pressurization, this straight part is reliably plastically deformed, so even if it is a long flat oval flexible duct, the flat part with the straight part as the boundary Is reliably maintained.

In the second invention, in the first invention,
In the pressurizing step, the round tube type flexible duct is held for a predetermined time while being held from above and below.

  According to said structure, a flat part is reliably maintained by pressing the linear part of the boundary of an arc-shaped outer peripheral surface and a flat outer peripheral surface reliably.

In the third invention, in the first or second invention,
The large-diameter press member is supported at both ends, and the small-diameter press member is cantilevered.

  According to the above configuration, since the small-diameter press member is cantilevered, the round tube type flexible duct can be easily inserted from the free side, and there is no need to support the free end after the insertion. The large-diameter press member is rigid at both ends, so that rigidity is secured. Even if it is a long and small-diameter round tube type flexible duct, not only the cantilever small-diameter press member but also the round tube together with the large-diameter press member supported at both ends Since the flexible duct is clamped from above and below, the linear portion extending in the axial direction that forms the boundary between the arc-shaped outer peripheral surface and the flat outer peripheral surface of the flat oval flexible duct held between them is reliably pressed and plastic Deform. For this reason, even if a springback occurs after pressurization, the straight portion is reliably plastically deformed. Therefore, even in a long flat oval flexible duct, the flat portion is surely separated from the straight portion. Kept.

In a fourth invention, in any one of the first to third inventions,
The core material is made of a steel wire.

  That is, the steel wire has high rigidity and is suitable as a material for maintaining the shape, but has a high yield point and a large amount of springback. However, in the present invention, the linear portion extending in the axial direction that becomes the boundary between the arc-shaped outer peripheral surface of the flat oval flexible duct and the flat outer peripheral surface is surely pressed and plastically deformed. Is extremely small. For this reason, even if it is a long flat oval type flexible duct, a flat part is reliably maintained on the boundary of a straight line part.

In a fifth invention, in any one of the first to fourth inventions,
The sheet material is formed by bonding an aluminum foil and a pet film.

  According to said structure, since an aluminum foil becomes difficult to tear by bonding a pet film, the flexible duct which has a flat oval cross section with high fracture strength and elasticity is obtained.

  In a sixth aspect of the present invention, a round tube type flexible duct having an annular cross-section that is extendable in the axial direction is provided with a core material spirally wound to maintain the shape and a sheet material that covers the core material. Thus, the present invention is directed to a method for forming a flat oval type flexible duct in which a cross-sectional shape is formed of two linear portions extending in parallel with the major axis direction and an arc-shaped portion.

And the molding method is
A preparation step of preparing the round tube type flexible duct;
A pair of large-diameter press members having an arcuate outer peripheral surface are arranged at a predetermined distance above and below, and a pair of arc-shaped outer peripheral surfaces having a smaller diameter than the large-diameter press member is disposed between the pair of large-diameter press members. A mounting step in which the small-diameter press member is arranged at a distance from side to side, and the round tube type flexible duct is inserted from one end side of the pair of small-diameter press members,
While holding the round tube type flexible duct from above and below so that the large-diameter press member and the small-diameter press member are in line contact with each other while bringing the large-diameter press member close to each other and separating the small-diameter press member from each other A pressing step for deforming the round tube type flexible duct;
The large-diameter press members are separated from each other, and a demolding step of demolding the small-diameter press members close to each other is performed.

  According to the above configuration, since the small-diameter press member is disposed inside the round tube type flexible duct, the insertion side cantilever is free unless a mechanism for supporting the insertion side is provided after the round tube type flexible duct is inserted. It becomes a state. However, since the large-diameter press member does not need to insert a round tube type flexible duct from one end side unlike the small-diameter press member, both ends can be supported and rigidity is ensured. For this reason, even if it is a long and small-diameter round tube flexible duct, not only the cantilevered small-diameter press member, but also the round tube-type flexible duct is sandwiched from above and below with the large-diameter press member supported at both ends. The linear portion extending in the axial direction that becomes the boundary between the arc-shaped outer peripheral surface and the flat outer peripheral surface of the flat oval flexible duct held between them is surely pressed and plastically deformed. Therefore, even if a springback occurs in the elastically deformed part after pressurization, this straight part is reliably plastically deformed, so even if it is a long flat oval flexible duct, the flat part with the straight part as the boundary Is reliably maintained.

  According to a seventh aspect of the present invention, a round tube type flexible duct having an annular cross section that is extendable in the axial direction is provided with a core material spirally wound to maintain the shape and a sheet material that covers the core material. Thus, the present invention is directed to a flat oval flexible duct molding apparatus for molding so that a cross-sectional shape is formed of two linear portions and an arc-shaped portion extending in parallel with the major axis direction.

And the molding device is
A pair of large-diameter press members having an arcuate outer peripheral surface and movable in the vertical direction;
A pair of small-diameter press members having an arcuate outer peripheral surface having a smaller diameter than the large-diameter press member and movable in the left-right direction;
First driving means for moving the pair of large-diameter press members in the vertical direction;
Second driving means for moving the pair of small diameter press members in the left-right direction;
The first driving means is driven, the second driving means is driven while pressing the upper and lower sides of the round tube type flexible duct by the large diameter press member, and the left and right sides of the round tube type flexible duct are driven by the small diameter press member. Control means for pulling the side surface from the inside and deforming the round tube type flexible duct while holding the round tube type flexible duct from above and below so that the large diameter press member and the small diameter press member are in line contact with each other. ing.

  According to the above configuration, the first driving means is driven by the control means, and the round pipe type flexible duct is pressed by the large diameter press member while the second driving means is driven and the round pipe type flexible member is driven by the small diameter press member. Pull the left and right sides of the duct from the inside to deform the round tube type flexible duct. At this time, since the small-diameter press member is arranged inside the round tube type flexible duct, the insertion side is free cantilevered unless a mechanism for supporting the insertion side is provided after the round tube type flexible duct is inserted. . However, since the large-diameter press member does not need to insert a round tube type flexible duct from one end side unlike the small-diameter press member, both ends can be supported and rigidity is ensured. For this reason, even if it is a long and small-diameter round tube flexible duct, not only the cantilevered small-diameter press member, but also the round tube-type flexible duct is sandwiched from above and below with the large-diameter press member supported at both ends. The linear portion extending in the axial direction that becomes the boundary between the arc-shaped outer peripheral surface and the flat outer peripheral surface of the flat oval flexible duct held between them is surely pressed and plastically deformed. Therefore, even if a springback occurs in the elastically deformed part after pressurization, this straight part is reliably plastically deformed, so even if it is a long flat oval flexible duct, the flat part with the straight part as the boundary Is reliably maintained.

In the eighth invention, in the seventh invention,
The large diameter press member and the small diameter press member are made of a pipe material.

  According to said structure, if it is a pipe material, since a large diameter press member and a small diameter press member are lightweight, there is little bending by dead weight. Therefore, the linear portion extending in the axial direction that is the boundary between the arc-shaped outer peripheral surface and the flat outer peripheral surface of the flat oval flexible duct held by the large-diameter press member and the small-diameter press member from above and below is reliably pressed and plasticized. Since it is deformed, even if spring back occurs in the elastically deformed portion after pressurization, the amount of spring back is extremely small in this straight portion. Further, by using the pipe material, it becomes possible to insert another pipe having a large outer diameter, and it becomes possible to easily manufacture a flat oval flexible duct having a different outer diameter.

In the ninth invention, in the seventh invention,
The pair of large-diameter press members are composed of an upper die and a lower die that protrude to positions where pressing portions having arcuate outer peripheral surfaces are opposed to each other,
The small-diameter press member is made of a pipe material.

According to the above configuration, the upper mold and the lower mold having high rigidity can be configured. Therefore, the straight line extending in the axial direction is the boundary between the arc-shaped outer peripheral surface and the flat outer peripheral surface of the flat oval flexible duct held from above and below. The portion is further reliably pressed and plastically deformed. Therefore, even if a springback occurs in the elastically deformed part after pressurization, this straight part is reliably plastically deformed, so even if it is a long flat oval flexible duct, the flat part with the straight part as the boundary Is reliably maintained. In addition, by using a small-diameter press member as a pipe material, another pipe having a large outer diameter can be inserted, and a flat oval flexible duct having a different outer diameter can be easily manufactured .

  As described above, according to the present invention, the round tube type flexible duct having an annular cross section is sandwiched from above and below so that the large-diameter press member and the small-diameter press member having an arcuate outer peripheral surface are in line contact with each other. It is transformed into a flat oval type. For this reason, the linear part of the boundary between the arc-shaped outer peripheral surface and the flat outer peripheral surface can be reliably plastically deformed, and a flat oval flexible duct having a flat surface can be obtained with certainty.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

-Flexible duct configuration-
FIG. 1 shows a flat oval flexible duct 1 according to an embodiment of the present invention. FIG. 2 shows an enlarged cross-sectional view of the flat oval flexible duct 1. The flat oval flexible duct 1 is formed by alternately winding a core material 2 and a belt-like sheet material 3 for maintaining a shape in a spiral shape. The cross-sectional shape is composed of two linear portions and an arc-shaped portion extending in parallel with the major axis direction. Thus, the flat oval flexible duct 1 has a curved arcuate outer peripheral surface 1a and a substantially flat flat outer peripheral surface 1b, and the arcuate outer peripheral surface 1a and the flat outer peripheral surface 1b are linear. It continues in the straight line part 1c. That is, when the flat oval flexible duct 1 is viewed from the axial direction, the straight portion 1c has a semicircular shape (may be an arc shape) that forms the arc-shaped outer peripheral surface 1a and a straight line that forms the flat outer peripheral surface 1b. Located at the inflection point with the shape. The flat oval type flexible duct 1 is shortened shortly during transportation and extended in the axial direction during use so that fluid can be circulated in an air conditioner or the like. The dimensions are, for example, a short diameter of 70 mm, a long diameter of 135 mm, and a length of 8 m when extended. In addition, since the length at the time of shortening is about 0.6 m, transportation is easy.

  The said core material 2 consists of steel wires, for example. The steel wire only needs to have rigidity sufficient to maintain the shape of the flat oval flexible duct 1, and its outer diameter and material are not limited. Moreover, the pitch of the spiral is not specifically limited, For example, the pitch at the time of expansion | extension shall be 25 mm. In the present embodiment, a material having a large yield point, that is, a large amount of springback may be used.

  The said sheet material 3 consists of what bonded together aluminum foil and a pet film, for example. Since the aluminum foil is not easily torn by sticking the pet film in this way, the flat oval flexible duct 1 having a flat oval cross section having a high breaking strength and being stretchable can be obtained.

-Flexible duct molding equipment-
Next, the configuration of the molding apparatus 10 for the flat oval flexible duct 1 will be described.

  3 to 5 show the molding apparatus 10 in each step. The molding apparatus 10 has a pair of large-diameter press members 11 having an arc-shaped outer peripheral surface and movable in the vertical direction, and an arc-shaped outer peripheral surface having a smaller diameter than the large-diameter press member 11 and moving in the left-right direction. A free pair of small diameter pressing members 12 are provided. The large diameter press member 11 and the small diameter press member 12 are made of a pipe material. Since it is light if it is a pipe material, it is easy to operate because there is little bending due to its own weight. For example, a vinyl chloride round tube or a metal pipe is used.

  In the present embodiment, the outer diameter of the large-diameter press member 11 is 60 mm, the outer diameter of the small-diameter press member 12 is 38 mm, and the length is about 9 m in order to obtain the shape after molding of the flat oval flexible duct 1. It has become. The wall thickness may be a size that can maintain a certain degree of rigidity. Each of the pair of large-diameter press members 11 is connected to the first driving means 13 at one end side and is configured to be movable in the vertical direction. The other end side of the pair of large-diameter press members 11 is connected to a casing (not shown) of the molding apparatus 10 and has a double-end support structure. The pair of small-diameter press members 12 are connected to the second driving means 14 at one end side and configured to be movable in the left-right direction, and the other end side is not supported and is free.

  The molding apparatus 10 includes a controller 15 as control means. The controller 15 drives the first drive means 13 and presses the upper and lower sides of a flexible duct having an annular cross section (hereinafter referred to as a conventional flexible duct, hereinafter referred to as a round tube type flexible duct 101) by the large-diameter press member 11. The second driving means 14 is driven while being attached, and the left and right side surfaces of the round tube type flexible duct 101 are pulled from the inside by the small-diameter press member 12 so that the large-diameter press member 11 and the small-diameter press member 12 are in line contact with each other. The round tube type flexible duct 101 is deformed in a state where the round tube type flexible duct 101 is sandwiched from above and below.

-Manufacturing method of flat oval type flexible duct-
Next, the manufacturing method of the flat oval type flexible duct 1 concerning this embodiment is demonstrated.

  First, in the pre-forming step, the core material 2 made of a steel wire and the strip-shaped sheet material 3 are alternately wound in a spiral shape to form a circular tube-shaped flexible duct 101 having an annular cross-sectional shape. In this embodiment, the outer diameter is about 108 mm and the length is about 8 m. The round tube type flexible duct 101 is formed by a known winding device.

  Next, as shown in FIG. 3, in the mounting process, the controller 15 drives the first driving means 13 to arrange the pair of large-diameter press members 11 up and down with a predetermined distance. Further, the second driving means 14 is driven by the controller 15, and the pair of small diameter press members 12 are arranged with a distance left and right between the pair of large diameter press members 11. The round tube type flexible duct 101 is inserted from one end side of the pair of small diameter press members 12 which are not supported. Thus, since the small diameter press member 12 is cantilevered, the round tube type flexible duct 101 can be easily inserted from the free side.

  Next, as shown in FIG. 4, in the pressurizing step, the controller 15 drives the first drive means 13 to bring the large diameter press members 11 close to each other, and the controller 15 drives the second drive means 14 to drive the small diameter press. The round tube type flexible duct 101 is deformed while the round tube type flexible duct 101 is sandwiched from above and below so that the large diameter press member 11 and the small diameter press member 12 are in line contact with each other while the members 12 are separated from each other.

  In the pressurizing step, the round tube type flexible duct 101 is held for a predetermined time (for example, 3 seconds) while being sandwiched from above and below. Thus, a flat part is reliably maintained by pressing firmly the linear part 1c of the boundary of the circular-arc-shaped outer peripheral surface 1a and the flat outer peripheral surface 1b.

  At this time, the large-diameter press member 11 is supported at both ends and the small-diameter press member 12 is cantilevered, but it is not necessary to support a free end portion after insertion. Since the large diameter press member 11 is supported at both ends, rigidity is ensured. Even if it is a long and small diameter round tube type flexible duct 101, not only the cantilever small diameter press member 12 but also the large diameter press member supported at both ends. This is to hold the round tube type flexible duct 101 together with 11 from above and below. Accordingly, the linear portion 1c extending in the axial direction that becomes the boundary between the arc-shaped outer peripheral surface 1a and the flat outer peripheral surface 1b of the flat oval flexible duct 1 held between them is reliably pressed and plastically deformed.

  Finally, as shown in FIG. 5, in the demolding step, the large-diameter press members 11 are pulled apart from each other, and the small-diameter press members 12 are brought close to each other and taken out from the insertion side to be demolded. Then, the compressed core material 2 is spring-backed to be a flat oval type consisting of two linear portions and an arc-shaped portion whose cross-sectional shape extends parallel to the major axis direction. The flat oval flexible duct 1 may be transported while being shortened in the axial direction and extended during piping.

  Thus, since the straight portion 1c is reliably pressed and plastically deformed, even if a springback occurs in the elastically deformed portion after pressurization, the amount of springback of the straight portion 1c is extremely small. For this reason, even if it is a long flat oval type flexible duct 1, a flat part is reliably maintained on the boundary of the linear part 1c.

  Although the said core material 2 consists of a steel wire suitable as a material which has high rigidity and maintains a shape, the amount of springbacks is large. However, in the present embodiment, since the straight portion 1c extending in the axial direction that becomes the boundary between the arc-shaped outer peripheral surface 1a and the flat outer peripheral surface 1b of the flat oval flexible duct 1 is reliably pressed and plastically deformed, Even with the high core material 2, the amount of spring back of the straight portion 1c is extremely small.

-Effect of the embodiment-
Therefore, according to the flat oval type flexible duct 1 according to the present embodiment, the round tube type flexible duct 101 is arranged from above and below so that the large diameter press member 11 and the small diameter press member 12 having arcuate outer peripheral surfaces are in line contact with each other. It is held and deformed into a flat oval shape. For this reason, the straight portion 1c at the boundary between the arc-shaped outer peripheral surface 1a and the flat outer peripheral surface 1b can be reliably plastically deformed, and the flat oval flexible duct 1 having a flat surface can be obtained.

(Other embodiments)
The present invention may be configured as follows with respect to the above embodiment.

  That is, in the above-described embodiment, the small-diameter press member 12 has a cantilever support structure, but a member that supports one end side of the small-diameter press member 12 may be attached and supported at both ends after the mounting step. However, as described above, in the present embodiment, the round tube type flexible duct 101 is sandwiched from above and below together with the large-diameter press member 11 supported at both ends, and therefore it is not always necessary to support both ends.

  In the above embodiment, the small-diameter press member 12 has one end connected to the second drive means 14, but it is not always necessary to provide the second drive means 14, and if it is configured to be movable in the left-right direction, As the large-diameter press member 11 is moved up and down by the first drive means 13, it is forced to expand to the left and right. By doing so, the number of parts of the molding apparatus 10 is reduced.

  The small-diameter press member 12 does not necessarily have a smaller diameter than the large-diameter press member 11. For example, the flat oval is composed of two linear portions and an arc-shaped portion whose cross-sectional shape extends in parallel with the short-diameter direction. When manufacturing a type | mold flexible duct, it is good also as a diameter larger than the large diameter press member 11. FIG.

  In the above embodiment, the pair of large-diameter press members 11 are arranged at a predetermined distance in the vertical direction, and the pair of small-diameter press members 12 are arranged at a distance in the left-right direction. The diameter press member 11 is arranged at a predetermined distance on the left and right, the pair of small diameter press members 12 are arranged at a distance in the vertical direction therebetween, and the pair of large diameter press members 11 are moved in the left-right direction by the first driving means 13. The pair of small-diameter press members 12 may be moved in the vertical direction by the second driving means 14 so as to sandwich the round tube type flexible duct 101 from the left and right. However, the arrangement of the above embodiment is desirable because the load can be reliably supported by the large-diameter press member 11 supported at both ends.

  Moreover, in the said embodiment, although the flat oval type flexible duct 1 assumed that the core material 2 and the strip | belt-shaped sheet material 3 were alternately wound spirally, the whole core material 2 wound helically was made. You may make it cover with the sheet material 3 of 1 sheet or several.

  In the said embodiment, although the sheet | seat material 3 shall have bonded aluminum foil and a pet film, besides this, what vapor-deposited aluminum to a pet film (aluminum vapor deposition pet), a polyester nonwoven fabric, a polyethylene nonwoven fabric, etc. Can be considered. That is, the material of the sheet material 3 is not particularly limited as long as it is a sheet-like material such as cloth or paper.

  Although not shown in detail, the pair of large-diameter press members 11 may be an upper die and a lower die that protrude to positions where pressing portions having arcuate outer peripheral surfaces face each other. In this case, since an upper mold and a lower mold having high rigidity can be configured, a straight line extending in the axial direction that serves as a boundary between the arc-shaped outer peripheral surface 1a and the flat outer peripheral surface 1b of the flat oval flexible duct 1 held from above and below. The portion 1c is further reliably pressed and plastically deformed.

  The length of the flat oval flexible duct 1 is not particularly limited, and it is sufficient that the core material 2 is about five in order to maintain the shape. For example, if the pitch is 25 mm, the minimum length needs to be about 10 cm. . The maximum length is limited to the length of the large diameter press member 11 and the small diameter press member 12. In particular, if the upper mold and the lower mold as described above are used, the rigidity of the pair of large-diameter press members 11 is sufficiently maintained, so that there is no length limitation. There is no particular limitation on the outer diameter of the flat oval flexible duct 1. What is necessary is just to set the outer diameter of the large diameter press member 11 and the small diameter press member 12, and the outer diameter of the round tube type flexible duct 101 before shaping | molding according to the shape to shape | mold.

  In the said embodiment, although the large diameter press member 11 and the small diameter press member 12 shall consist of pipe materials, a cylindrical thing may be sufficient. The small-diameter press member needs to have an arc-shaped outer peripheral surface at least outside the periphery of the portion in line contact with the large-diameter press member, but the inner side must always have an arc-shaped outer peripheral surface. There is no.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or a use.

  As described above, the present invention is useful for a flexible duct that is piped in a narrow space such as a ceiling in an air conditioner or the like.

The flat oval type flexible duct concerning embodiment of this invention is shown, (a) is a side view, (b) is a front view. It is an expanded sectional view of a flat oval type flexible duct. The shaping | molding apparatus of the flat oval type flexible duct in a mounting process is shown, (a) is a side view, (b) is a front view. FIG. 4 is a view corresponding to FIG. 3 in a pressurizing step. FIG. 4 is a view corresponding to FIG. 3 in a demolding process.

DESCRIPTION OF SYMBOLS 1 Flat oval type flexible duct 1a Arc-shaped outer peripheral surface 1b Flat-shaped outer peripheral surface 1c Straight part 2 Core material 3 Sheet material 10 Forming apparatus 11 Large diameter press member 12 Small diameter press member 13 First drive means 14 Second drive means 15 Controller ( Control means)
101 Round tube type flexible duct

Claims (9)

A flat comprising two linear portions and an arc-shaped portion that includes a core material for holding the shape and a sheet material that covers the core material, and that is extendable in the axial direction and whose cross-sectional shape extends parallel to the major axis direction. A method of manufacturing an oval flexible duct,
A preforming step of alternately winding the core material and the strip-shaped sheet material in a spiral shape to form a circular tube-type flexible duct having an annular cross-sectional shape;
A pair of large-diameter press members having an arcuate outer peripheral surface are arranged at a predetermined distance above and below, and a pair of arc-shaped outer peripheral surfaces having a smaller diameter than the large-diameter press member is disposed between the pair of large-diameter press members. A mounting step in which the small-diameter press member is arranged at a distance from side to side, and the round tube type flexible duct is inserted from one end side of the pair of small-diameter press members,
While holding the round tube type flexible duct from above and below so that the large-diameter press member and the small-diameter press member are in line contact with each other while bringing the large-diameter press member close to each other and separating the small-diameter press member from each other A pressing step for deforming the round tube type flexible duct;
A method for producing a flat oval type flexible duct, comprising: a step of releasing the large-diameter press members from each other and a step of releasing the small-diameter press members close to each other. In the manufacturing method of the flat oval type flexible duct according to claim 1,
In the pressurizing step, a flat oval type flexible duct manufacturing method is characterized in that the round tube type flexible duct is held for a predetermined time while being held from above and below. In the manufacturing method of the flat oval type flexible duct according to claim 1 or 2,
A method for producing a flat oval type flexible duct, wherein the large-diameter press member is supported at both ends and the small-diameter press member is cantilevered. In the manufacturing method of the flat oval type flexible duct according to any one of claims 1 to 3,
The said core material consists of steel wires, The manufacturing method of the flat oval type flexible duct characterized by the above-mentioned. In the manufacturing method of the flat oval type flexible duct according to any one of claims 1 to 4,
The method for producing a flat oval type flexible duct, wherein the sheet material is formed by bonding an aluminum foil and a pet film. In order to maintain the shape, a spirally wound core material and a sheet material covering the core material are provided, and a circular tube-shaped flexible duct having an annular cross-section that can be expanded and contracted in the axial direction is pressed to make the cross-sectional shape a major axis direction. A method for forming a flat oval type flexible duct, which is formed so as to consist of two linear portions and an arc-shaped portion extending in parallel with each other,
A preparation step of preparing the round tube type flexible duct;
A pair of large-diameter press members having an arcuate outer peripheral surface are arranged at a predetermined distance above and below, and a pair of arc-shaped outer peripheral surfaces having a smaller diameter than the large-diameter press member is disposed between the pair of large-diameter press members. A mounting step in which the small-diameter press member is arranged at a distance from side to side, and the round tube type flexible duct is inserted from one end side of the pair of small-diameter press members,
While holding the round tube type flexible duct from above and below so that the large-diameter press member and the small-diameter press member are in line contact with each other while bringing the large-diameter press member close to each other and separating the small-diameter press member from each other A pressing step for deforming the round tube type flexible duct;
A molding method of a flat oval type flexible duct, comprising: a mold releasing step of separating the large diameter press members from each other and releasing the small diameter press members close to each other. In order to maintain the shape, a spirally wound core material and a sheet material covering the core material are provided, and a circular tube-shaped flexible duct having an annular cross-section that can be expanded and contracted in the axial direction is pressed to make the cross-sectional shape a major axis direction. A flat oval type flexible duct forming apparatus for forming two linear portions extending in parallel with each other and an arc-shaped portion,
A pair of large-diameter press members having an arcuate outer peripheral surface and movable in the vertical direction;
A pair of small-diameter press members having an arcuate outer peripheral surface having a smaller diameter than the large-diameter press member and movable in the left-right direction;
First driving means for moving the pair of large-diameter press members in the vertical direction;
Second driving means for moving the pair of small diameter press members in the left-right direction;
The first driving means is driven, the second driving means is driven while pressing the upper and lower sides of the round tube type flexible duct by the large diameter press member, and the left and right sides of the round tube type flexible duct are driven by the small diameter press member. Control means for pulling the side surface from the inside and deforming the round tube type flexible duct while holding the round tube type flexible duct from above and below so that the large diameter press member and the small diameter press member are in line contact with each other. An apparatus for forming a flat oval type flexible duct. In the flat oval type flexible duct molding apparatus according to claim 7,
The apparatus for forming a flat oval type flexible duct, wherein the large-diameter press member and the small-diameter press member are made of a pipe material. In the flat oval type flexible duct molding apparatus according to claim 7,
The pair of large-diameter press members are composed of an upper die and a lower die that protrude to positions where pressing portions having arcuate outer peripheral surfaces are opposed to each other,
The apparatus for forming a flat oval type flexible duct, wherein the small-diameter press member is made of a pipe material.

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