JPH10122448A - Spirally reinforced hose, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a run-off fold from being projected into an inner pipe when a hose is bent while high flexibility is kept. SOLUTION: A flexible tubular wall thickness part 2a of an inner pipe 2 is swollen outwardly in the radial direction of a hose, and formed in a spiral corrugation shape. A corrugated part located outside in the bending direction of the flexible tubular wall thickness part 2a when bent is expanded approximately straight, and the corrugated part located inside in the opposite bending direction absorbs the compressive stress to form a run-off fold 2b to be projected outside in the radial direction of the hose.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforced helical hose used at low pressure or negative pressure, such as a suction hose or a duct hose, and a method of manufacturing the same. More specifically, a spiral reinforcing hose in which a hard reinforcing wire is spirally wound on the outer surface of an inner tube made of a soft band spirally wound in the hose axis direction and welded together, and rotationally driven on a mandrel A soft belt-shaped body supplied from the first extruder is welded to the spiral shaft while being wound in the direction of the hose axis so that a part thereof overlaps to form an inner tube, and a second band is formed on the outer surface of the inner tube. The present invention relates to a method for manufacturing a spiral reinforced hose which is welded to the inner tube while spirally winding a hard reinforcing wire supplied from an extruder in the axial direction of the hose.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Utility Model Publication No. 7-38786, Japanese Utility Model Application Laid-Open No. 48-52922 and Japanese Utility Model Application Laid-Open No. 50-117413, a hard reinforcing wire is provided on the outer surface. By bending the inner tube made of a soft band-shaped body wound spirally, the portion of the inner tube disposed between the hard reinforcing wires protrudes inside the inner tube to form a relief fold. To increase flexibility and facilitate bending. In addition, as a method for manufacturing a spiral reinforced hose, for example, as disclosed in Japanese Patent Publication No. 59-19811, a plurality of spiral shafts are helically protruded along the outer peripheral surface of a cantilevered mandrel, and these spiral shafts are formed. The soft belt and the hard reinforcing wire supplied from the extruder are supplied toward the machine, and the spiral shaft is rotated in the same direction at the same rotation speed by the driving means, so that a part of the soft belt has a certain width. While forming the inner tube by being wound so as to wrap, a hard reinforcing wire is spirally wound around the outer surface of the inner tube, and a portion of the inner tube disposed between the hard reinforcing wires is formed by the inner tube. Some manufacture helical reinforced hoses that are recessed inward.

[0003]

However, in such a conventional spiral reinforced hose and a method for manufacturing the same, when the inner tube is bent, the flexible tube disposed between the hard reinforcing wires of the inner tube. Since the inner portion in the bending direction of the meat portion protrudes inward in the radial direction of the hose to form a relief fold, not only is the flexibility inferior, but also the resistance of the fluid passing through the inner tube during use increases, and the flow rate changes. Or turbulence or pulsation.

An object of the present invention is to prevent escape folds from protruding into the inner tube during bending while maintaining high flexibility.
The invention according to claim 3 has, in addition to the object of the invention according to claim 2, a step of the inner tube generated by lamination of the soft strips while increasing the adhesive strength of the soft strips and preventing peeling. It is intended to have a uniform thickness. A fourth aspect of the present invention, in addition to the object of the second or third aspect of the present invention, aims to further improve the external appearance by preventing the exposure of the joining step while further increasing the bonding strength between the flexible belts. It is what it was. The invention according to claim 5 is
In addition to the object of the invention described in claim 4, it is another object of the present invention to further increase the adhesive strength of the hard reinforcing wire to the inner pipe.

[0005]

In order to achieve the above-mentioned object, according to the first aspect of the present invention, a flexible pipe wall disposed between hard reinforcing wires of an inner pipe is provided. And a helical waveform formed by swelling outward in the radial direction of the hose. According to the second aspect of the present invention, air is blown from the axially intermediate portion of the mandrel toward the inner surface of the uncured inner tube wound around the spiral shaft, and is disposed between the hard reinforcing wires of the inner tube. The flexible pipe wall is formed in a spiral waveform by expanding the diameter of the flexible pipe outward in the radial direction of the hose. According to a third aspect of the present invention, in the configuration of the second aspect of the present invention, the soft strip supplied from the first extruder is substantially two thirds in the width direction.
Are added so as to overlap each other. According to a fourth aspect of the present invention, in the configuration of the second or third aspect of the present invention, the joining step portion is formed by overlapping the soft belt-shaped members and projecting spirally outward in the radial direction of the hose. It is characterized by adding a configuration in which a hard reinforcing wire is wound and welded at the same pitch to cover. According to a fifth aspect of the present invention, in the structure of the fourth aspect of the present invention, the rigid reinforcing wire supplied from the second extruder is formed on a joining plane facing the outer surface of the inner tube and on the joining plane. The present invention is characterized in that a configuration is provided in which a joining step portion of the soft band-shaped body and a fitting portion to be fitted are provided.

[0006]

According to the first aspect of the present invention, the flexible tube portion is bent at the time of bending by bulging the flexible tube portion of the inner tube radially outward to form a spiral waveform. The corrugated portion located on the outside in the direction of extension extends substantially linearly, and the corrugated portion located on the inside on the opposite side in the bending direction absorbs compressive stress and forms a relief fold that projects outward in the hose radial direction. is there.
The invention according to claim 2 is characterized in that the blown air expands the uncured state of the flexible pipe wall in the radial direction of the hose to form a spiral waveform, thereby forming the flexible pipe wall at the time of bending. The corrugated portion located on the outer side in the bending direction of the portion extends substantially linearly, and the corrugated portion located on the opposite side in the bending direction absorbs compressive stress and forms a relief fold projecting outward in the hose radial direction. It is something that can be done. According to a third aspect of the present invention, there is provided a configuration in which the soft strip supplied from the first extruder is wound around the configuration described in the second aspect so that approximately 2/3 of the width thereof overlaps in the width direction. Because of the addition, approximately 2
By overlapping the three layers with / 3 overlap, the bonding area of the soft strips can be increased and the thickness of the soft strips can be reduced. According to a fourth aspect of the present invention, in the configuration according to the second or third aspect, a joining step portion spirally projecting outward in the radial direction of the hose formed by overlapping the soft belts covers the joining step portion. As described above, the configuration in which the hard reinforcing wire is wound and welded at the same pitch is added, so that the joining step portion of the soft strip that is easily peeled is pressed and welded by the hard reinforcing wire. According to a fifth aspect of the present invention, in addition to the configuration of the fourth aspect, the rigid reinforcing wire supplied from the second extruder is formed on a joining plane facing the outer surface of the inner tube and on the joining plane. The structure in which the joining step of the soft band and the fitting part to be fitted are provided is added, so that the fitting part of the hard reinforcing wire supplied from the second extruder is connected to the joining step of the soft band. It is fitted and wound around.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, as shown in FIGS. 2 and 3, six spiral shafts B are spirally protruded along the outer peripheral surface of the cantilevered mandrel A at an inclination angle of, for example, about 6 degrees. Are rotated in the same direction at the same rotational speed by driving means (not shown), and the soft belt-like body 1 supplied from the first extruder C toward the spiral shafts B is Then, the hard reinforcing wire 3 supplied from the second extruder D is wound around the outer surface of the wound soft belt 1 in a spiral manner so as to partially overlap in the width direction of the hose. The spiral reinforcing hose H is continuously manufactured by being spirally wound in the axial direction.

The first extruder C has a conventionally well-known structure. For example, a soft synthetic resin such as soft vinyl chloride is heated and softened and extruded to form a soft strip 1 having an extremely thin wall thickness. At the same time, the uncured soft strip 1 is supplied to the spiral shafts B.
In the present embodiment, as shown in FIG. 4, the soft band 1 supplied from the first extruder C is wound so that approximately 2/3 of the width thereof overlaps, thereby forming an uncured soft band. While the spiral shafts B are rotated in the direction of the hose axis while being superimposed on the hose axis direction by three layers with a substantially uniform thickness, they are sent out in the axial direction of the hose. The overlapping of the above-mentioned soft strips 1 constitutes an inner tube 2 from which the joining step portion 1a projects spirally outward in the radial direction of the hose.

[0009] The second extruder D is also the first extruder C
Similarly to the above, it has a conventionally well-known structure. For example, a hard synthetic resin such as hard vinyl chloride is heated and softened and extruded to form a hard reinforcing wire body 3 having a substantially semicircular cross section or a semicylindrical shape. The unhardened hard reinforcing wire 3 is supplied to the outer surface of the inner tube 2 sent out in the axial direction of the hose, and wound in a spiral shape. In the present embodiment, at the time of extrusion molding of the hard reinforcing wire body 3, the joining flat surface 3a facing the outer surface of the inner tube 2 and the joining step portion 1a of the soft belt-like body 1 formed on the joining flat surface 3a are fitted. And a fitting step 3a of the soft belt-shaped body 1.
The hard reinforcing wire 3 is wound at the same pitch so as to be fitted and covered.

The mandrel A is provided with air blowing means 4 for blowing air from the axially intermediate portion A1 toward the inner surface of the uncured inner tube 2 wound around the spiral shaft B. Means 4
The inner tube 2 in the uncured state is pressed outward in the hose radial direction by air blown out from the inner tube 2. Air blowing means 4
In the case of the present embodiment, the mandrel A is formed in a hollow pipe shape, and an air supply passage 4a is defined in the inside thereof in the axial direction of the hose, and a connecting pipe 4a 'is formed at the base end of the air supply passage 4a. And an air supply source such as an air compressor (not shown) through the air supply path 4a.
A plurality of air outlets 4b penetrating from the middle part in the axial direction to the outside of the mandrel A are radially opened. In the case of the present embodiment, a plurality of spacers B1 are fixedly arranged at appropriate intervals in the hose axis direction on the outer periphery of the mandrel A, and the spiral shafts B are rotatably mounted on these spacers B1. A plurality of engaging holes B to be supported
By opening 2 ..., the spiral shaft B ...
To prevent floating. Further, in the air supply path 4a, a shaft B3 for supporting the spiral shafts B in a substantially horizontal direction in the hose axis direction via a mandrel A and spacers B1 is non-rotatably disposed.

Next, a method for manufacturing such a spiral reinforced hose H will be described. First, as shown in FIG.
Of the spiral shafts B rotating at the same rotational speed in the same direction, the uncured soft band-shaped body 1 supplied from the first extruder C overlaps approximately 2/3 in the width direction. It is spirally wound in the axial direction.
As a result, as shown in FIG. 4, the soft strips 1 are superimposed three layers at a substantially uniform thickness in an uncured state, and at the same time, the soft strips 1 are spirally joined outward in the hose radial direction by overlapping of the soft strips 1. The step 1a protrudes.

Then, the above-mentioned soft belt-like bodies 1 remain in the state of being superimposed three layers at a time, and thereafter are gradually heat-welded to form the inner tube 2. As a result, since the contact area between the overlapping soft strips 1 is large, the adhesive strength of the soft strips 1 is increased, there is no danger of peeling, and the thickness of the soft strip 1 can be reduced. The step of the inner tube 2 caused by the lamination of the strips 1 is small, and the thickness of the entire inner tube 2 becomes uniform.

As shown in FIG. 2, the uncured overlapping soft strips 1 are sent out in the direction of the hose axis by the rotation of the spiral shafts B. As shown in FIG. The hard reinforcing wire 3 supplied from the machine D is spirally wound in the hose axis direction at the same pitch so as to cover the fitting portion 3b of the joining plane 3a by fitting the fitting step 3a.

The fitting portion 3b of the hard reinforcing wire 3
Is fitted to the joining step 1a of the soft belt-shaped body 1, and while the joining step 1a is still covered, it is gradually thermally welded thereafter. As a result, the bonding step 1a of the soft strip 1 which is easily peeled is pressed by the hard reinforcing wire 3 and welded.
The bonding strength of the soft strips 1 can be further enhanced, and the appearance can be improved because the joining step 1a is not exposed. Further, the fitting portion 3b of the hard reinforcing wire 3 can be connected to the joining step of the soft strip 1. Since it is fitted and wound around 1a, the adhesive strength of the hard reinforcing wire 3 to the inner tube 2 can be further increased.

The unhardened inner tube 2 and the hard reinforcing wire 3 are further rotated by the rotation of the spiral shafts B.
The hard reinforcing wire 3 is sent out along with the unhardened inner tube 2 in the axial direction of the hose, and when they reach the axial middle portion A1 of the mandrel A, the air blowing means 4 as shown in FIG. From the air outlets 4b of the inner pipe 2
Air is radially blown toward the inner surface of the hose and presses outward in the hose radial direction. Thereby, the flexible pipe wall portion 2a disposed between the hard reinforcing wires 3 of the inner pipe 2 in an uncured state.
Is swelled outward in the radial direction of the hose and expanded in diameter, but the portion near the joining step 1a around which the hard reinforcing wire 3 is wound is only pressed against the joining plane 3a of the hard reinforcing wire 3, The helical reinforcement hose H is formed without being able to expand its diameter outward in the hose radial direction. As a result, the portion near the joining step 1a around which the hard reinforcing wire 3 is wound cannot be expanded outward by the blown air, and is strongly pressed against the joining plane 3a of the hard reinforcing wire 3, so that the soft reinforcing wire 3 is soft. The mutual adhesive strength between the band and the hard reinforcing wire can be increased.

The spiral reinforcing hose H is sent out from a spiral shaft B of a mandrel A, but is rotated, so that it is floated in a water tank (not shown) and cut to a fixed length to be completed.

The helical reinforced hose H obtained by the above-described manufacturing method is, as shown in FIG.
a bulges outward in the radial direction of the hose and expands to form a spiral waveform. Therefore, when the spiral reinforcing hose H is bent as shown in FIG. 1 (b), the corrugated portion positioned outside the bending direction of the flexible pipe wall portion 2a extends substantially linearly, and the inside in the bending direction on the opposite side to this. The relief fold 2b is formed in the corrugated portion located at the position of absorbing the compressive stress and projecting outward in the hose radial direction.
As a result, the helical reinforced hose H is maintained with high flexibility and is easily bent, and does not increase the resistance of the fluid passing through the inner tube when being bent, does not change the flow rate, and does not generate turbulence or pulsation. .

Further, even if the soft band-like body 1 constituting the escape fold 2b protrudes most outward in the radial direction of the hose, the soft band-like body 1 goes out of the outer end of the hard reinforcing wire 3 which is the surface of the spiral reinforcing hose H. It is preferable to prevent the hose from slipping and prevent the soft band 1 constituting the escape fold 2b from being damaged.

The structure of the air blowing means 4 is not limited to the one shown in the drawing, and may have another structure as long as it has the same function. Furthermore, spiral shaft B ...
The structure of the spacers B1.
The structure is not limited to the illustrated one, and other structures may be used as long as they have the same function.

[0020]

As described above, according to the first aspect of the present invention, the flexible pipe wall portion of the inner pipe is formed in a spiral waveform by bulging outward in the hose radial direction. Accordingly, at the time of bending, the corrugated portion located on the outside in the bending direction of the flexible tube wall portion extends substantially linearly, and the corrugated portion located on the opposite side in the bending direction absorbs the compressive stress and the hose Since the relief fold projecting outward in the radial direction is formed, it is possible to prevent the relief fold from protruding into the inner tube during bending while maintaining high flexibility. Therefore, as compared with the conventional one in which the portion arranged between the hard reinforcing wires of the inner tube protrudes inward to form a relief fold when the inner tube is bent, the inner tube passes through the inner tube at the time of bending use while maintaining easy bending. The resistance of the fluid does not increase, there is no change in the flow rate, and no turbulence or pulsation occurs.

According to a second aspect of the present invention, the blown air expands the uncured flexible pipe wall in the radial direction of the hose to form a spiral waveform, so that the flexible pipe can be flexed when bent. The corrugated portion located on the outer side in the bending direction of the tubular wall portion extends substantially linearly, and the corrugated portion located on the opposite side in the bending direction absorbs compressive stress and protrudes outward in the hose radial direction. Since the folds are formed, the escape folds can be prevented from protruding into the inner tube at the time of bending while maintaining high flexibility. Therefore, as compared with the conventional one in which the portion arranged between the hard reinforcing wires of the inner tube protrudes inward to form a relief fold when the inner tube is bent, the inner tube passes through the inner tube at the time of bending use while maintaining easy bending. The resistance of the fluid does not increase, there is no change in the flow rate, and no turbulence or pulsation occurs. In addition, the blown air causes the flexible pipe wall to bulge outward in the radial direction of the hose and expand in diameter. However, the outer surface portion facing the hard reinforcing wire cannot be expanded outward and the hard reinforcing wire cannot be expanded. Is strongly pressed against the joint plane, and the mutual bonding strength between the soft strip and the hard reinforcing wire can be increased.

According to a third aspect of the present invention, in addition to the effect of the second aspect of the present invention, the soft belt-shaped body overlaps by about 2/3 and has
By being superimposed on the layers, the bonding area between the flexible strips is increased and the thickness of the flexible strips can be reduced, so that the bonding strength between the flexible strips is increased to prevent peeling while increasing the bonding strength. The step of the inner tube generated by the lamination of the inner tubes is small, and the wall thickness can be made uniform.

According to a fourth aspect of the present invention, in addition to the effect of the second or third aspect, since the joining step portion of the soft strip which is easily peeled off is pressed and welded by the hard reinforcing wire, the soft strips can be joined together. The appearance can be improved by preventing the exposure of the joining step portion while further increasing the bonding strength.

According to a fifth aspect of the present invention, in addition to the effect of the fourth aspect, the fitting portion of the hard reinforcing wire supplied from the second extruder is fitted to the joining step of the soft band. As a result, the adhesive strength of the hard reinforcing wire to the inner tube can be further increased.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of a spiral reinforcing hose showing one embodiment of the present invention, wherein (a) shows a state of extending straight, and (b) shows a state of bending.

FIG. 2 is a partially cutaway front view showing an embodiment of an apparatus for manufacturing a spiral reinforced hose of the present invention.

FIG. 3 is an enlarged vertical sectional side view taken along line (3)-(3) in FIG. 2;

FIG. 4 is a longitudinal sectional front view showing a partially enlarged uncured state immediately after a soft band and a hard reinforcing wire are wound.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Soft belt-like body 1a Joining step part 2 Inner pipe 2a Flexible pipe wall part 3 Hard reinforcing wire body 3a Joining plane 3b Fitting part A Mandrel A1 Axial halfway B Spiral shaft C First extruder D Second Extruder

Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29K 105: 20 B29L 9:00 23:18

Claims (5)

[Claims] 1. A spiral reinforcement in which a hard reinforcing wire (3) is spirally wound around the outer surface of an inner tube (2) composed of a soft band (1) spirally wound in the axial direction of a hose and welded integrally. In the hose, a flexible pipe wall (2a) disposed between the hard reinforcing wires (3, 3) of the inner pipe (2)
A helical reinforced hose formed by bulging outward in a hose radial direction to form a spiral waveform. 2. A soft belt (1) supplied from a first extruder (C) is overlapped on a spiral shaft (B) that is rotationally driven on a mandrel (A) so that a part thereof overlaps. The inner pipe (2) is formed by welding while being wound in the axial direction of the hose, and a hard reinforcing wire (3) supplied from a second extruder (D) is formed on the outer surface of the inner pipe (2) in the axial direction of the hose. In the method for manufacturing a helical reinforced hose which is welded to the inner tube (2) while being spirally wound in an uncured state wound around the spiral shaft (B) from the axially intermediate portion (A1) of the mandrel (A). The air is blown toward the inner surface of the inner pipe (2), and the flexible pipe wall (2a) disposed between the hard reinforcing wires (3, 3) of the inner pipe (2).
Of a spiral reinforced hose formed by expanding the outer diameter in the radial direction of the hose to form a spiral waveform. 3. The helical reinforced hose according to claim 2, wherein the soft belt-like body (1) supplied from the first extruder (C) is wound so that substantially two-thirds in the width direction thereof overlap. Manufacturing method. 4. A joining step (1a) spirally projecting outward in the radial direction of the hose formed by overlapping the soft strips (1) at the same pitch so as to cover the joining step (1a). A hard reinforcing wire (3) wound and welded.
Or the manufacturing method of the helical reinforcement hose of 3. 5. A joining plane (3a) facing the outer surface of the inner tube (2) and a joining plane (3a) on the hard reinforcing wire (3) supplied from the second extruder (D). The method for manufacturing a helical reinforced hose according to claim 4, further comprising a fitting portion (3b) fitted with the joining step portion (1a) of the soft belt-like body formed in the above.