JP2016084901A - Tubular element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tubular element that satisfies all conditions of making a fine diameter, a long life formation of a product, and improved tensile strength and flexibility.SOLUTION: This invention relates to a tubular element including an inner layer, a reinforcing layer and an outer layer and the like. A section of a strip body 5 constituting the reinforcing layer crossing with a longitudinal direction thereof is a shape of smooth curved lines. At least a part of the tubular element has a contact region where a part of the surface of the inner layer and the surface of reinforcing layer opposing against the inner layer are contacted to each other at a section crossing at a right angle with a longitudinal direction of the tubular element, and a non-contact region where the other part of the surface of the inner layer and the surface of reinforcing layer opposing against the inner layer forms a clearance between the inner layer and the reinforcing layer.SELECTED DRAWING: Figure 1

Description

The present invention relates to a tubular member that is inserted into a tube and used in advance for insertion into a narrow tube in order to convey gas, liquid, instruments, and the like.

In the past, in the fields of food, pharmaceuticals, chemistry, medical care, analytical instruments, etc., long tubular members with excellent strength have been widely used in order to transport gas, liquid, instruments and the like to piping and narrow spaces. In the medical field, a medical tubular member inserted into a body cavity or organ for treatment or examination is used.

Generally, a tubular member used for insertion into a thin tube includes a resin tube having an inner core bore extending in the longitudinal direction, and a reinforcing layer, an outer layer, and the like covering the tube. The tubular member is inserted in advance in order to convey gas, liquid, instruments and the like to narrow pipes and narrow places, and therefore, a reinforcing layer that supplements mechanical strength can be said to be one of important components. . When a tubular member is repeatedly inserted into or pulled out from a thin site such as a pipe, a part of the tubular member, in particular, the inner layer-reinforcing layer peels off due to the resistance with the tube wall of the inserted object, or There is a known problem that the tubular member is damaged during use, such as the reinforcing layer being disconnected due to friction between the reinforcing layers.

As the shape of the striate body used as the reinforcing layer, a rectangular shape may be used for reducing the diameter of the tubular member and reducing the thickness of the reinforcing layer (for example, Patent Document 1).

In the case of a rectangular shape, the tubular member can be made thinner overall and the reinforcing layer can be made thinner than a round shape, while the reinforcing layers rub against each other with long-term use, and the acute angle portion of the rectangular shape is the reinforcing layer. May cause damage to itself. Since damage to the reinforcing layer results in disconnection, the product life tends to be shorter compared to the round shape.

Moreover, the tubular member of Patent Document 2 has a wire coil made of a wire having a non-circular cross section, and the wire coil is embedded in the resin layer (inner layer) to suppress peeling at the interface between the reinforcing layer and the resin layer. It is characterized by.

Patent Document 2 improves the adhesion between the inner layer and the reinforcing layer of the tubular member, that is, the strength against tension (hereinafter referred to as tensile strength), but tends to deteriorate the flexibility by being embedded in the inner layer.

In addition, in order to improve the adhesion between the inner layer of the tubular member and the reinforcing layer, a specification is known in which an intermediate layer is provided on the inner layer. By improving the adhesion between the striation bodies of the intermediate layer and the reinforcing layer, it contributes to the prevention of breakage of the tubular member as described above. While the adhesion is improved, there is a concern that the cost will increase due to the wage and material costs for applying the intermediate layer.

Japanese Patent No. 2523405 JP 2013-208355 A

The subject of this invention is providing the tubular member which satisfy | fills all of diameter reduction, prolongation of a product life, improvement of tensile strength, and a softness | flexibility.

The gist of the present invention is as follows.

(1) A tubular member including an inner layer, a reinforcing layer, an outer layer, and the like, wherein the cross section perpendicular to the longitudinal direction of the striatum constituting the reinforcing layer has a smooth curved shape, and the longitudinal direction of the tubular member In the cross section orthogonal to the inner layer and a part of the surface where the reinforcing layer faces the inner layer, the contact area where the inner layer and the reinforcing layer face the inner layer, and another part of the surface where the inner layer and the reinforcing layer face the inner layer, A non-contact region forming a gap between the inner layer and the reinforcing layer is provided in at least a part of the tubular member.
(2) The gap provided between the inner layer and the reinforcing layer is filled with the outer layer material without any gap.
(3) The reinforcing layer has a braided structure, and the cross section perpendicular to the longitudinal direction of the filaments constituting the reinforcing layer is substantially elliptical.
(4) The reinforcing layer is characterized by the following proportional expression.

X: Y = 1: 1.5 to 4.5 (proportional expression 1)
And Y: Z = 1: 0.8 or less (proportional expression 2)

X: striate of reinforcing layer, short diameter part of cross section perpendicular to longitudinal direction Y: striate of reinforcing layer, long diameter part of cross section perpendicular to longitudinal direction Z: in cross section perpendicular to longitudinal direction of tubular member, The length of the contact portion between the inner layer and the reinforcing layer Note that the cross section perpendicular to the longitudinal direction of the filaments constituting the reinforcing layer has a substantially line-symmetric shape.

(5) The adhesive strength between the inner layer and the reinforcing layer has an adhesive strength that is twice or more that of a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area.
(6) The flexibility of the tubular member is 10% or more as compared with a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area.

According to the present invention, the excellent effects described below can be expected.

(1) By providing a gap between the inner layer and the reinforcing layer, the contact surface between the inner layer and the reinforcing layer is reduced, and as a result, it contributes to an improvement in flexibility in the entire tubular member.
(2) Since the outer layer is filled in the gap provided between the inner layer and the reinforcing layer, adhesion with the inner layer is improved while maintaining flexibility.
(3) Only by devising the shape of the striate body of the reinforcing layer, the adhesion and flexibility can be improved at low cost without increasing the cost.
(4) By improving the adhesiveness with the inner layer, the tensile strength of the tubular member is improved, which contributes to the reduction of breakage such as separation of a part of the tubular member, particularly the inner layer and the reinforcing layer.
(5) Compared with the conventional rectangular shape, the friction between the reinforcing layers is alleviated, which contributes to prevention of deterioration of the product life due to disconnection or the like.
(6) Furthermore, by using the reinforcing layer characterized by the above-described proportional expression, it is easy to design a tubular member that satisfies all of the requirements for reducing the diameter, extending the product life, improving the tensile strength and flexibility.

Example of longitudinal cross-sectional view (schematic diagram) in the longitudinal direction of the reinforcing layer of the present invention An example of a longitudinal cross-sectional view (schematic diagram) in the tubular member of the present invention An example of an enlarged view (schematic diagram) at the interface between the inner layer and the reinforcing layer in FIG. Example of enlarged view (schematic diagram) of interface between inner layer and reinforcing layer in conventional tubular member Schematic diagram showing the flexibility test measurement method

Hereinafter, the basic configuration of the tubular member of the present invention will be described with reference to the drawings.

In the tubular member 1 of FIG. 2, an inner layer 2, a reinforcing layer 3 (striate body 5), and an outer layer 4 are applied.

The inner layer 2 is a resin tube having an inner core pit extending in the length direction.

Examples of the material of the inner layer 2 include fluororesins such as polytetrafluoroethylene (PTFE), thermoplastic resins such as polyolefin and nylon, and thermoplastic elastomers, especially considering the chemical resistance and antibacterial resistance. Fluorine resin is preferred. The fluorine resin may be, for example, a mixture of PTFE and other fluorine resins.
In addition, it is not restricted to these materials, If it is resin, it will be suitably selected as needed.

The inner layer 2 contains additives and colorants as needed, and is not particularly limited.

Further, an intermediate layer is appropriately provided on the inner layer 2, and the material is not particularly limited.
When the intermediate layer is provided, the reinforcing layer is not in the inner layer but in contact with the intermediate layer, and the inner layer 2 in this specification includes the intermediate layer.

The reinforcing layer 3 is a coil (winding) or braiding of the filament 5 on the inner layer 2. From the viewpoint of strength, braiding is preferred.

The material of the filament 5 is preferably a metal, but is not limited to this, and other materials (for example, resin) may be used as long as the material has higher rigidity than the inner layer 2 and the outer layer 4. . Specific examples of the metal material include copper, SUS, titanium, nickel titanium alloy, steel, copper alloy, tungsten, and the like, and are not particularly limited.

A rectangular wire is generally known as a cross-sectional shape orthogonal to the longitudinal direction of the filament 5, but in the present invention, it is a shape consisting of a smooth curve and orthogonal to the longitudinal direction of the tubular member 1. In the cross section, a part of the surface where the inner layer 2 and the reinforcing layer 3 are opposed to the inner layer is a contact region where the inner layer 2 and the reinforcing layer 3 are opposed to each other, and another part of the surface where the inner layer 2 and the reinforcing layer 3 are opposed to the inner layer. However, it has the non-contact area | region which forms a clearance gap between the inner layer 2 and the reinforcement layer 3 (striate body 5) in at least one part of a tubular member.

Specifically, since it is generally easy to obtain, an approximately oval shape is preferable. However, only a part of the surface facing the inner layer is in contact with the inner layer, and the inner layer 2 and the reinforcing layer 3 (striated body 5). If it is the shape which a clearance gap produces between, it will not specifically limit. Since there is little contact with the inner layer 2, the flexibility as the tubular member 1 is remarkably improved, and the outer layer 4 is filled in the gap without any gap, so that the inner layer 2 can be kept in close contact while maintaining flexibility. Can be improved.

Furthermore, it is preferable that it is the following proportional formula as a concrete specification of the reinforcement layer 3 (striate body 5).

X: Y = 1: 1.5 to 4.5 (proportional expression 1)
And Y: Z = 1: 0.8 or less (proportional expression 2)

X: striate of reinforcing layer, short diameter part of cross section perpendicular to longitudinal direction Y: striate of reinforcing layer, long diameter part of cross section perpendicular to longitudinal direction Z: in cross section perpendicular to longitudinal direction of tubular member, The length of the contact portion between the inner layer and the reinforcing layer Note that the cross section perpendicular to the longitudinal direction of the filaments constituting the reinforcing layer has a substantially line-symmetric shape.

Proportional formula 1 shows the ratio of the minor axis part of the cross section perpendicular to the longitudinal direction in the linear body 5 of the reinforcing layer 3 and the ratio of the major axis part, and the value of Y is closer to 1 based on X The larger the circle, the more elliptical it is.
Since the reinforcing layer 3 (wire body 5) needs an appropriate tensile strength, it is necessary to maintain a cross-sectional area of a certain level or more. As a result, the closer to a circle, the larger the actual diameter of X, and the smaller the ellipse. Become.
The numerical value of Y is preferably 1.5 or more from the viewpoint of reducing the diameter of the tubular member 1, and it is possible to reduce the diameter while maintaining the tensile strength.
Furthermore, the preferable range is 2.5 or more, and the effect of reducing the diameter becomes remarkable.
Moreover, the numerical value of Y is 4.5 or less, and a more preferable range is 3.5 or less. This is because the length of the contact portion between the inner layer 2 and the reinforcing layer 3 can be kept short, and the effect of flexibility is expected as the diameter is reduced.

Proportional formula 2 shows the ratio of the length of the longitudinal section in the longitudinal section of the filament 5 of the reinforcing layer 3 and the length of the contact section between the inner layer 2 and the reinforcing layer 3 in the longitudinal section of the tubular member 1. In addition, with Y as a reference, the closer the Z value is to 1, the larger the contact portion between the inner layer 2 and the reinforcing layer 3.
The smaller the contact portion between the inner layer and the reinforcing layer, the better the flexibility, and the outer layer material filled between the inner layer and the reinforcing layer tends to have better adhesion strength.
The numerical value of Z is preferably 0.8 or less. From the viewpoint of flexibility, the more preferable range is 0.7 or less, and the product life can be extended by improving the tensile strength and flexibility.

The shapes of the portions of the inner layer 2 and the reinforcing layer 3 that are in contact with the striate body 5 do not necessarily match. Therefore, if they do not match, the striate body 5 bites into the inner layer 2 to some extent. Although there may be bite, it is preferable that a gap is provided between the linear body 5 and the inner layer 2 of the reinforcing layer 3 without biting, and further, the material of the outer layer 4 is filled.

The adhesion strength between the inner layer 2 and the reinforcing layer 3 is twice or more that of a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area. If it is 5 times or more, there is no possibility of breakage due to a decrease in adhesion strength, which is more preferable.

The flexibility of the tubular member 1 is 10% or more as compared with a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area.

The outer layer 4 is made of resin and applied on the reinforcing layer 3.

Examples of the material of the outer layer 4 include thermoplastic resins such as fluorine resin, polyolefin, urethane, and nylon, and thermoplastic elastomers. In view of flexibility, thermoplastic elastomers such as polyolefin, urethane, and nylon are particularly preferable. In addition, it is not restricted to these materials, What is necessary is just a resin, and it selects suitably according to a use.

The material of the outer layer 4 is preferably a material having good fluidity of the material at the melting point or higher from the viewpoint of moldability and the like. This is because the gap between the inner layer and the reinforcing layer is sufficiently filled to contribute to the improvement of the adhesion between the inner layer and the reinforcing layer.

In addition, if necessary, a marker, a coating with a wet polymer or the like may be used, and is not particularly limited.

Hereinafter, the tubular member 1 of the present invention shown in FIG. 2 will be described more specifically with reference to examples. However, the scope and manufacturing method of the present invention are not limited thereto.

(Examples 1-6, Comparative Examples 1-5)
In Example 1, as the inner layer 2, a tube made of PTFE is produced by extrusion molding with an inner diameter of 6.0 μm and an outer diameter of 6.2 μm (thickness of 100 μm).
Around the inner layer 2, as a reinforcing layer 3, a line composed of a substantially elliptical shape with a short diameter (X) of 100 μm × long diameter (Y) of 150 μm and a length of a contact portion between the inner layer 2 and the reinforcing layer 3 (Z) of 105 μm and SUS. The shaped body 5 is braided with a pitch of 4.5 mm and 16 strokes.
Around the reinforcing layer 3, as the outer layer 4, a polyolefin-based elastomer is coated by extrusion molding so as to have an outer diameter of 6.8 μm (thickness 100 μm).

Example 2 is a substantially oval shape of Example 1 with a minor axis (X) of 78 μm × major axis (Y) of 195 μm, a length of a contact portion with the inner layer 2 and the reinforcing layer 3 (Z) of 137 μm, and a line made of SUS. It has been changed to a strip 5.

Example 3 is a substantially oval having a short diameter (X) of 65 μm × a long diameter (Y) of 230 μm and a length of a contact portion between the inner layer 2 and the reinforcing layer 3 (Z) of 160 μm. The shape is changed to a striate body 5 made of SUS.

Example 4 is a substantially oval shape of Example 1 with a short diameter (X) 58 μm × long diameter (Y) 260 μm, the length of the contact portion with the inner layer 2 and the reinforcing layer 3 (Z) 182 μm, and a line made of SUS. It has been changed to a strip 5.

Example 5 is a substantially oval shape of Example 1 having a minor axis (X) of 78 μm × major axis (Y) of 195 μm, a length of a contact portion with the inner layer 2 and the reinforcing layer 3 (Z) of 117 μm, and a line made of SUS. It has been changed to a strip 5.

Example 6 is a substantially oval shape of Example 1 with a minor axis (X) of 78 μm × major axis (Y) of 195 μm, a length of a contact portion with the inner layer 2 and the reinforcing layer 3 (Z) of 156 μm, and a line made of SUS. It has been changed to a strip 5.

Comparative Example 1 is the same as Example 1 except that it is changed to a striated body 5 made of a circular shape of φ140 μm and SUS.

Comparative Example 2 is a line composed of a substantially elliptical shape and a SUS of Example 1 having a minor axis (X) of 112 μm × major axis (Y) of 135 μm, a length of a contact portion with the inner layer 2 and the reinforcing layer 3 (Z) of 95 μm. It has been changed to a strip 5.

Comparative Example 3 is a substantially oval shape of Example 1 with a minor axis (X) of 55 μm × major axis (Y) of 275 μm, a length of a contact portion with the inner layer 2 and the reinforcing layer 3 (Z) of 193 μm, and a line made of SUS. It has been changed to a strip 5.

Comparative Example 4 is a substantially oval shape of Example 1 with a minor axis (X) of 78 μm × major axis (Y) of 195 μm, a length of a contact portion with the inner layer 2 and the reinforcing layer 3 (Z) of 176 μm, and a line made of SUS. It has been changed to a strip 5.

Comparative Example 5 is the same as Example 1, except that it is changed to a linear body 5 having a rectangular shape with an outer diameter of 78 μm × 195 μm and SUS.

About Examples 1-6 and Comparative Examples 1-5, adhesive strength, a softness | flexibility, and diameter reduction are evaluated, and a result is shown in Table 1.

Each evaluation method and criteria are shown below.

(Measurement method of adhesion strength)
In the measurement sample, the outer layer 4 is peeled off by about 10 mm from the end of the tubular member 1, and the peeled outer layer part and the exposed reinforcing layer part are sandwiched between chucks of a measuring machine.
At a pulling speed of 50 [mm / min], the outer layer is pulled in the peeling direction, and the maximum strength [N] at a peeling length of 80 mm is measured. A general tensile testing machine is used as a measuring machine.
When the adhesion strength is strong and the outer layer 4 and the reinforcing layer 3 cannot be peeled and the outer layer is damaged, for example, it is 25 N or more when measurement is impossible.
(Evaluation of adhesion strength)
In addition, as a judgment, a measured value of 25N or more (having an adhesion strength of 5 times or more compared with a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area and no risk of breakage) ◎, 20N or more and 25N Less than 10 (having an adhesion strength of 2 times or more compared to a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area) is less than 10N, and less than 10N is classified as x because there is a possibility of breakage.

(Measurement method of flexibility)
As shown in FIG. 4, the tubular member 1 is arranged linearly so as to be sandwiched between three φ8 mm mandrels 6. At this time, the distance between the lower two mandrels serving as fulcrums is 45 mm, and the mandrel that pressurizes the tubular member 1 is disposed between the lower two mandrels serving as fulcrums. An intermediate mandrel is pressed in the direction of arrow N at a speed of 500 mm / min, and the maximum strength [N] at a distance of 35 mm is measured from the start of pressing.
(Evaluation of flexibility)
Moreover, as a judgment, less than 16N, which is particularly excellent in flexibility (20% flexibility compared to a reinforcing layer made of a flat rectangular wire having an equivalent cross-sectional area), ◎, 18N or less (having an equivalent cross-sectional area) Compared to a reinforcing layer made of a flat rectangular wire, 10% flexibility) is marked as ◯.

(Evaluation of narrowing)
Of the reinforcing layer 3 (striate body 5), a circular one is used as a reference (100%), and a small diameter ratio [%] is indicated. When the diameter reduction ratio is significantly less than 60%, ◎, 60% or more and less than 80% are evaluated as ◯, and 80% or more when the diameter reduction effect is small.

(Table 1)

In Examples 1 to 6, that is, when X: Y = 1: 1.5 to 4.5 and Y: Z = 1: 0.8 or less, diameter reduction, improvement in adhesion and flexibility, Favorable results are obtained for all the characteristics, especially when Examples 2 and 3, that is, X: Y = 1: 2.5 to 3.5 and Y: Z = 1: 0.7 or less are particularly advantageous. Sex is seen.

In the adhesion, when X: Y = 1: 1.5 to 4.5 and Y: Z = 1: 0.8 or less, the adhesion strength is 25 N or more and all have the same cross-sectional area. Compared with a reinforcing layer made of a flat rectangular wire, an improvement in adhesion of 5 times or more can be obtained.

In all cases, the flexibility is improved by 10% or more as compared with a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area. Furthermore, when X: Y = 1: 3.5 or less, the contact portion between the inner layer and the reinforcing layer can be kept short, and therefore, compared with a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area. However, an improvement of 20% or more is observed, and particularly superiority is observed.

The above embodiment is merely an example of the present invention, and various modifications and applications can be made without departing from the spirit of the present invention.

The tubular member of the present invention has excellent diameter, long product life, excellent tensile strength and flexibility. It is expected to be used in a wide range of industries, such as industrial applications such as infrastructure inspection for water, gas, tunnels, bridges, etc.

DESCRIPTION OF SYMBOLS 1 Tubular member 2 Inner layer 3 Reinforcement layer 4 Outer layer 5 Line 6 Mandrel P Crevice X Streak of reinforcement layer, short diameter portion Y of longitudinal section Cross section of reinforcement layer, long diameter portion Z of longitudinal section Tubular member Length of the contact portion with the inner layer and the reinforcing layer in the longitudinal section of

Claims (6)

A tubular member including an inner layer, a reinforcing layer, an outer layer, etc.
The cross section perpendicular to the longitudinal direction of the striatum constituting the reinforcing layer is a shape formed of a smooth curve,
And,
In a cross section perpendicular to the longitudinal direction of the tubular member,
A contact region where the inner layer and a part of the surface of the reinforcing layer facing the inner layer are in contact with each other;
And
A non-contact region in which the inner layer and another part of the surface of the reinforcing layer facing the inner layer form a gap between the inner layer and the reinforcing layer;
A tubular member characterized by comprising: at least a part of the tubular member.
In the gap provided between the inner layer and the reinforcing layer,
The outer layer material is filled without gaps,
The tubular member according to claim 1.
The reinforcing layer has a braided structure,
And,
The cross section perpendicular to the longitudinal direction of the striatum constituting the reinforcing layer is substantially elliptical,
The tubular member according to claim 1 or 2.
The tubular member according to claim 1, wherein the reinforcing layer is characterized by the following proportional expression.

X: Y = 1: 1.5 to 4.5 (proportional expression 1)
And Y: Z = 1: 0.8 or less (proportional expression 2)

X: striate of reinforcing layer, short diameter part of cross section perpendicular to longitudinal direction Y: striate of reinforcing layer, long diameter part of cross section perpendicular to longitudinal direction Z: in cross section perpendicular to longitudinal direction of tubular member, The length of the contact portion between the inner layer and the reinforcing layer Note that the cross section perpendicular to the longitudinal direction of the filaments constituting the reinforcing layer has a substantially line-symmetric shape.
The adhesion strength between the inner layer and the reinforcing layer is characterized by comprising two or more times compared to a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area,
The tubular member according to any one of claims 1 to 4.
The flexibility of the tubular member is 10% or more in comparison with a reinforcing layer made of a rectangular wire having an equivalent cross-sectional area,
The tubular member according to any one of claims 1 to 5.

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