JP2009142551A - Flexible hose - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the resistance to shrinkage of a flexible hose which is used for an electric cleaner or the like when a negative pressure is applied. <P>SOLUTION: The flexible hose is formed by constituting a hose wall by spirally winding a flexible band and integrating its side edges by bonding and adhering spiral reinforcers inside. In this case, the section of the hose wall between adjacent hard reinforcers includes two first parts which are adjacent to the hard reinforcers along the axial direction of the hose on the cross section along the axial direction of the hose and a second part which is positioned substantially in the center of the section and along the axial direction of the hose. The cross section of the second part is offset outside in the radial direction of the hose with respect to the first parts. Further, deformation inhibiting parts may be arranged in parts inside the hose where the first parts are adjacent to the hard reinforcers for preventing the first parts from falling toward the inside of the hose. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a flexible hose made of a synthetic resin, which is formed in a bellows shape and excellent in flexibility, and particularly relates to a hose for a vacuum cleaner.

As such a flexible hose, the one disclosed in Patent Document 1 is known, and as this type of hose, a hose mainly composed of a thermoplastic resin having excellent thermoformability is widely used. For example, a resin-coated reinforcing wire in which a hard steel wire is coated with a thermoplastic resin is spirally wound around the outer periphery of the mandrel, and the outer surface of the resin-coated reinforcing wire (hard reinforcing body) is made of a soft thermoplastic resin. Covers the tube or spirally rolls a tape made of a soft thermoplastic resin to form a hose wall, and is formed by pulling from the mandrel and forming a hose wall and a resin-coated reinforcing wire bonded and integrated It has been known. Further, in Patent Document 2, a flexible strip formed by a so-called spiral molding method in which a flexible strip is spirally wound around a hose molding shaft and adjacent side edges are joined and integrated by a hard resin reinforcement. A sex hose is disclosed.
JP 2002-139180 A JP 2002-39451 A

Such a flexible hose is required not only to have strength and durability, but also to be flexible (flexible) and to be light in weight so that it can be easily handled. Furthermore, when using for a vacuum cleaner, it is requested | required that it should have moderate shrinkage resistance so that a hose may not shrink in the length direction by the negative pressure which generate | occur | produces by the suction | inhalation of a cleaner.

However, it has not been easy to achieve both flexibility and shrinkage resistance of the flexible hose. In recent years, in particular, from the viewpoint of lightening, resource saving, and material saving, the wall of the hose has become thinner, while the output of the vacuum cleaner has been increased. There was a problem that sometimes it was easy to shrink. Further, when the thickness of the hose wall is increased so that the hose is not easily contracted, not only the hose becomes heavy but also the flexibility of the hose tends to be lost.

Therefore, an object of the present invention is to provide a flexible hose which is rich in flexibility and excellent in shrinkage resistance.

As a result of intensive studies, the inventors have adopted a flexible hose wall that has a specific cross-sectional shape between hard reinforcements, which improves shrinkage resistance and achieves various characteristics required for the hose. As a result, the present invention was completed.

In the present invention, a flexible strip made of a soft synthetic resin formed in a predetermined cross section is wound in a spiral shape, and the adjacent side edges are bonded and integrated to form a hose wall, and a spiral is formed inside the hose wall. A flexible hose formed by attaching a rigid reinforcement wound in a shape, and a hose wall in a section between adjacent rigid reinforcements is adjacent to the rigid reinforcement in a cross section along the hose axial direction And two first parts along the hose axial direction and a second part located along the hose axial direction at a substantially central part of the section, and the second part is outside the hose radial direction with respect to the first part. It is a flexible hose characterized by having a cross section that is offset at the right.

In the flexible hose, the first portion of the hose wall is provided on the inner portion of the hose where the first portion of the hose wall is adjacent to the hard reinforcement body along the hard reinforcement body, and the first portion of the hose is provided. You may form the deformation | transformation prevention part which prevents the collapse to an inner side (Claim 2).

According to the present invention, a hose having effectively improved shrinkage resistance when negative pressure is applied by a vacuum cleaner or the like can be obtained, and various characteristics of the hose such as flexibility can be improved in a balanced manner. it can.

Furthermore, when a deformation preventing portion is provided in a portion adjacent to the first portion of the hard reinforcement body as a preferred embodiment of the present invention, an effect that the shrinkage resistance of the hose can be improved more effectively is obtained.

Hereinafter, based on drawings, the hose for vacuum cleaners which shows the embodiment of the flexible hose of the present invention as an example is explained. 1 shows the overall appearance of the vacuum cleaner, FIG. 2 is a partial sectional view of a flexible hose according to an embodiment of the present invention, and FIG. 3 is a partially enlarged sectional view of the hose wall of the hose shown in FIG. FIG. 4 is a view showing an example of a flexible strip constituting the hose wall.

In FIG. 1, the vacuum cleaner hose A has one end of the hose A connected to an intake port provided in the vacuum cleaner body 10 via a connection pipe 11, and the other end of the hose A is connected to the hand operating unit 12. The extension pipe 13 and then the floor nozzle 14 are continuously connected to the hand operation unit 12 to constitute a vacuum cleaner.

As shown in FIG. 2, in the hose A for a vacuum cleaner, a flexible hose wall 1 is formed of a soft synthetic resin in a bellows shape as a whole, and the hose is shaped and reinforced on the inner peripheral surface of the hose wall. A hard reinforcing body 6 that prevents the hose from collapsing due to negative pressure is spirally attached. The hose wall 1 made of a soft synthetic resin has a cross-sectional shape as shown in FIG. FIG. 3 shows the lower side of the figure as the inside of the hose.

Examples of the soft synthetic resin constituting the hose wall of the present invention include ethylene vinyl acetate resin (EVA), soft vinyl chloride resin (PVC), low density polyethylene resin (LDPE), and thermoplastic urethane elastomer (TPU). The soft synthetic resin material can be used. As will be described later, there is an advantage that a flexible strip constituting the hose wall can be formed by extrusion molding or can be bonded by heat welding. is not.

The hard reinforcing body 6 of the present invention is made of a metal wire such as a steel wire or a hard steel wire, a resin-coated metal wire coated with a resin, or a hard resin such as a polypropylene resin, a high-density polyethylene resin or a polyamide resin. A hard resin wire extruded into a shape can be used. Since the hard reinforcing body is attached to the hose wall, it is preferable to select one having good adhesiveness with the adhesive to be used or one that can be thermally welded. FIG. 3 shows an example in which a steel wire 61 provided with a resin coating 62 is used as the hard reinforcement body 6.

Below, the cross-sectional shape of a hose wall which is a structure peculiar to the hose wall of the flexible hose A of this invention is demonstrated. FIG. 3 shows a partial cross-sectional view of the hose wall 1 and the hard reinforcement body 6 along the hose axial direction. That is, the hose wall 1 has attachment portions 7 and 7 formed so as to cover and surround the outer periphery of the hose of the hard reinforcement body 6, and is bonded to the hard reinforcement body 6 at the attachment portion 7. Further, in the section between the adjacent hard reinforcement bodies 6 and 6, the hose wall 1 is adjacent to the hard reinforcement bodies 6 and 6 and has two first portions 2 and 2 having a cross section along the hose axial direction. It is comprised by the 2nd part 3 which has a cross section along the hose axial direction located in the approximate center part of the area, and the connection parts 8 and 8 which connect between them. The second part 3 is offset with respect to the first parts 2 and 2 so as to be located outside the hose, and the connecting parts 8 and 8 connecting the first part and the second part are the main parts. In the embodiment, it has a cross section extending in the hose radial direction. The cross-sectional shape of the connecting portions 8 and 8 may be a cross section extending obliquely with respect to the radial direction.

In the present embodiment, the first portion 2 and the second portion 3 have substantially the same thickness. From the viewpoint of improving shrinkage resistance, the hard reinforcement body 6 side of the first portion 2 is made thicker than the other portions, or the central portion of the second portion 3 or the entire second portion 3 is compared with the other portions. It is preferable to make it thick.

Moreover, the surface of the hard reinforcement body 6 is formed in the hose inner part on the side adjacent to the hard reinforcement body 6 of the first part 2 of the hose wall from the hose inner peripheral surface of the first part 2 or the attaching part 7 toward the inside of the hose. The deformation prevention part 4 which protrudes so that it may follow is provided. In the present embodiment, the deformation preventing portion 4 is provided as a ridge that continues spirally along the hard reinforcing body 6. Such a deformation | transformation prevention part 4 can be manufactured by manufacture of the flexible strip by the extrusion molding mentioned later.

The flexible hose of the present invention can be manufactured by the so-called spiral molding method as follows. That is, the wire constituting the hard reinforcing body 6 is wound spirally around a known hose forming shaft. On the other hand, a high-temperature thermoplastic resin is extruded from an extruder equipped with an extrusion die having a predetermined cross section, and a flexible strip 5 having a cross section as shown in FIG. 4 is formed. The extruded flexible strip is spirally wound so as to cover the rigid reinforcement body 6 wound around the hose forming shaft, and the side edges 5a and 5b of the flexible strip 5 adjacent to each other are wound. The hose wall 1 and the hard reinforcement body 6 are attached together with the hose wall 1 by overlapping and bonding and integrating them on the hose outer peripheral side of the hard reinforcement body 6. An indefinite length flexible hose A can be obtained by continuously performing the above steps while continuously supplying the wire rod and the flexible strip 5 to the hose forming shaft. Adhesive integration of the side edges of the flexible strip 5 and attachment to the rigid reinforcement 6 can also be performed by heat fusion, in which case while the extruded flexible strip is still hot. It is preferable to wind and integrate them. Further, a thermoplastic adhesive or a solvent-based adhesive may be used.

The function and effect of the present invention will be described. In the present invention, the cross-sectional shape of the hose wall can improve the shrinkage resistance of the hose while maintaining the flexibility of the hose. Hereinafter, the mechanism for improving the shrinkage resistance of the hose will be described by paying attention to the behavior when the negative pressure acts on the hose by suction of a vacuum cleaner or the like.

FIG. 5 shows a hose when a negative pressure p and a compressive force F for compressing the hose are applied to a flexible hose having a conventional hose wall as shown in Patent Document 1 by suction with a vacuum cleaner or the like. It is a schematic diagram which shows the deformation | transformation state of wall 1 '.

When no negative pressure or compressive force is applied, the hose wall 1 ′, which is substantially linear, is pulled to the inside of the hose (lower side in the figure) by the action of the negative pressure p and has a curved shape as shown in the figure. . When a compression force F that further compresses the hose is applied in this state, the action line m on which the compression force F acts and the central portion 1c of the hose wall 1 ′ are separated from each other (offset amount d ′). A large bending moment (F * d ′) acts on the central portion 1c, and as a result, the hose wall 1 ′ is further deformed so as to bend toward the inside of the hose. As described above, in the conventional hose wall, the substantially straight hose wall 1 ′ is easily bent inside the hose due to the synergistic action of the negative pressure p and the compressive force F. The nature was low.

On the other hand, the schematic diagram of the deformation | transformation state of the hose wall 1 when the negative pressure p and the compressive force F act on the flexible hose of this invention is shown in FIG. Due to the action of the negative pressure p, the hose wall 1 is pulled inside the hose and becomes an illustrated shape curved toward the inside of the hose. However, in the present invention, the second portion 3 at the central portion of the hose wall is offset in advance to the outside of the hose, and therefore, between the action line m on which the compressive force F acts and the second portion 3 after deformation. The distance d of can be reduced. Therefore, the bending moment (F * d) acting on the second portion 3 by the compression force F can be reduced, and the action of bending the hose wall 1 toward the inside of the hose is reduced. Therefore, according to the flexible hose of this invention, shrinkage resistance can be improved compared with the conventional flexible hose.

Further, if the hose wall is formed by increasing the offset amount by which the second portion 3 of the hose wall is offset to the outside with respect to the first portion 2, the second portion 3 is acted on by the compression force F during the negative pressure operation. Positioned on the line m, the separation amount d is substantially zero, or the offset amount is further increased so that the separation amount d is negative (that is, the second portion 3 is compressed by a negative pressure when acting). ), The shrinkage resistance of the hose can be improved more effectively.

Furthermore, in the present embodiment, since the deformation preventing portion 4 is provided in the hose inner portion on the side adjacent to the hard reinforcement body 6 of the first portion 2, the hose wall 1 tends to deform toward the inside of the hose. At this time, since the deformation preventing portion 4 comes into contact with the hard reinforcing body 6, it is possible to prevent the first portion 2 from being deformed so as to fall down toward the inner side of the hose. The distance d between the two portions 3 can be further reduced, and the shrinkage resistance can be improved.

As described above, in the present invention, even a hose wall having a wall thickness equivalent to that of a conventional flexible hose can improve the shrinkage resistance during negative pressure action, while hindering the flexibility of the hose. There is nothing. Moreover, according to this invention, the shrinkage resistance at the time of a negative pressure action can also be improved, making the thickness of a hose wall thinner than the conventional flexible hose and improving the flexibility of a hose.

As mentioned above, although embodiment in this invention was shown, this invention is not restrict | limited to the said embodiment, The thing which changed each element is included in the range which does not change the property largely. For example, the deformation preventing part 4 is not limited to the above shape (continuous ridges), and a projecting deformation preventing part may be provided intermittently.

Further, the cross-sectional shape of the deformation preventing portion 4 may be as shown in the examples shown in FIGS. That is, in FIG. 7, the deformation preventing portion 4 ′ is formed by raising the resin coating 62 that covers the hard reinforcing body 6 toward the inside of the hose and the first portion 2, and in FIG. 8, it is provided on the hose wall. The deformation preventing part 4 '' is provided so as to have a slight gap between the side face part of the hard reinforcing body 6. The shape of the deformation preventing portion shown in FIGS. 7 and 8 also has an effect of preventing the first portion 2 from falling into the hose during a negative pressure action. Further, as shown in FIG. 8, when the deformation preventing portion 4 '' is provided so as to have a gap, the effect of easily improving the flexibility and flexibility of the hose can be obtained, and the negative pressure acts. In addition, this gap portion is brought into close contact with each other and exhibits a deformation preventing function.

Moreover, the manufacturing method of the flexible strip 5 which comprises a hose wall is not limited to extrusion molding, It sandwiches the soft resin flexible tape of the flat plate cross-sectional shape shape | molded separately with the heated shaping roller etc. Then, it may be manufactured by giving a cross-sectional shape necessary for the present invention.

Moreover, in the said embodiment, although the attachment part 7 of a hose wall is provided and attached so that the side surface part from the hose outer side of a rigid reinforcement body 6 to a hose inner side may be covered, the attachment part 7 and the rigid reinforcement body 6 are attached. Is particularly preferably bonded and integrated only at the outer portion of the hose. Since the side surface portion of the hard reinforcing body is not adhered, the attachment portion 7 and the side surface portion of the hard reinforcing body 6 can be separated from each other, so that the flexibility and flexibility of the hose can be improved. it can. Further, the hard reinforcing body 6 to be attached does not necessarily have to be adhered to the attachment portion 7 and may be non-adhered.

Moreover, in the said embodiment, although the number of the streaks of the hard reinforcement body 6 was 1 was shown, the number of streaks of the hard reinforcement body may be 2 or more, The shape of the flexible strip may be changed accordingly. Moreover, in the said embodiment, although the side edge part which the flexible strip adjoins was bonded and integrated in the adhesion part with the attachment part 7, ie, the rigid reinforcement body 6, this invention is limited to this. Instead, it may be bonded at the first part or the second part.

As described above, according to the present invention, it is possible to improve the shrinkage resistance when a negative pressure is applied in a vacuum cleaner or the like, and thus a flexible hose having excellent flexibility and shrinkage resistance is obtained. Can do.

The figure which shows the external appearance of the vacuum cleaner with which this invention is applied The fragmentary sectional view of the flexible hose of the embodiment of the present invention The expanded sectional view of the hose wall part of the flexible hose of the embodiment of the present invention The figure which shows embodiment of the flexible strip which comprises a hose wall Schematic diagram of deformation when negative pressure is applied to a conventional flexible hose Schematic diagram of deformation when negative pressure is applied to the flexible hose of the present invention The figure which shows the other example of a deformation | transformation prevention part The figure which shows the other example of a deformation | transformation prevention part

Explanation of symbols

A flexible hose 1, 1 ′ hose wall 2 first part 3 second part 4 deformation prevention part 5 flexible strip 6 hard reinforcement 7 attachment part 8 connection part

Claims (2)

A flexible strip made of a soft synthetic resin formed in a predetermined cross section is spirally wound and the adjacent side edges are bonded and integrated to form a hose wall, and spirally wound inside the hose wall A flexible hose formed by attaching a hard reinforcing body,
In the cross section along the hose axis direction, the hose wall in the section between adjacent hard reinforcements,
Two first portions adjacent to the rigid reinforcement and along the hose axial direction;
While having a second portion located in the approximate center of the section and along the hose axial direction,
A flexible hose characterized in that the second portion has a cross section offset to the outside in the hose radial direction with respect to the first portion. The first part of the hose wall is provided on the inner part of the hose where the first part of the hose is adjacent to the hard reinforcement body, along the hard reinforcement body to provide a protrusion that protrudes toward the inner side of the hose, preventing the first part from collapsing inside the hose. The flexible hose according to claim 1, wherein a deformation preventing portion is formed.

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