JPH02304289A - Compound reinforcing hose - Google Patents

Abstract

PURPOSE:To reduce kink and deformation of codes and improve each performance of pressure resistance and fatigue resistance and bending resistance of the codes by combining twisted codes of respective reinforcing layers made of the raw yarn fiber having the specified twist number and the code orientation direction and the pull elastic modulus. CONSTITUTION:Respective reinforcing layers 15 of a compound reinforcing hose 11 are numbered in order from inside to outside, and the mean value of twist number of reinforcing fiber codes 13 of the reinforcing layers at odd number is made larger than the mean value of twist number of reinforcing fiber codes 13 of the reinforcing layers at even number. Pairs of the reinforcing layers 15 are formed in order from inside to outside so that the twist number of the reinforcing fiber codes 13 of the inside reinforcing layers 15 of respective pairs of the layers is larger than the twist number of the reinforcing fiber codes 13 of the outside reinforcing layers 15. Next, the reinforcing layers 15 are located so that the twist number of the reinforcing fiber code 13 of the most inside reinforcing layer 15 is the largest among the twist number of the reinforcing fiber codes 13 of the respective reinforcing layers 15 and while the twist number of the reinforcing fiber codes 13 is reduced in order as moving from the inside reinforcing layers 15 to the outside reinforcing layers 15. The reinforcing layers 15 are made of the raw yarns more than two kinds and having different pull elastic modulus.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is a composite reinforced hose used for transmitting high-pressure fluids, for example, for transmitting high-pressure hydraulic pressure to hydraulic equipment for electrical work, or for transporting high-pressure pressure fluids. Related to composite reinforced hoses for high pressure transportation.

(Prior art) As a conventional composite reinforced hose for high pressure, for example,
There is something like the one shown in the figure. In Fig. 3, l is a composite reinforced hose, and the composite reinforced hose 1 includes a core tube 2 made of nylon resin and an aramid cord made by twisting two aramid fibers of 1500 d of twist on the outside of the core tube 2. The reinforcing layer 5 has four layers of reinforcing layers 5 arranged in parallel and spirally wound, and an outer skin 6 made of polyurethane resin and covering the outside of the reinforcing layer 5. outer skin 6
A protective layer 7 made of woven polyester fiber is interposed between and the reinforcement N5.

The reinforcing layer 5 has first to fourth layers from the inside to the outside of the reinforcing layer 5.
Reinforcement layer 5I, 5g, 53.5s (5 when representing
), then the first reinforcing layer 5. and a second reinforcing layer5. and the third reinforcing layer 5. An intermediate resin layer 8 is provided between and the fourth reinforcing layer 54 . The number of twists of the twisted cord of each reinforcing layer 5 is 20 to 30 per 101 for both the 1.2nd reinforcing layer 59.5 , 54 are both 10 or less. Further, the cord direction C of the aramid cord 3 constituting each reinforcing layer 5 is the same as that of the first reinforcing layer 5. from the fourth reinforcing layer 5
The cord orientation angle θ between the cord direction C of the aramid cord 3 and the circumferential line T of the aramid cord 3 is 4, respectively.
It increases sequentially at 9@, 56@, 59°, and 63°.

(Problems to be Solved by the Invention) However, such a composite reinforced hose 1, for example,
It is attached to hydraulic equipment for electrical work, and the hydraulic pressure is high pressure (for example, look f / c IIY ~ 700 kg r / c
r1), the composite reinforced hose 1 is significantly twisted and deformed. Further, when this hydraulic pressure is repeatedly applied, the composite reinforced hose 1 repeatedly twists and deforms and moves greatly, causing a problem in that it comes into contact with equipment and the human body, which is dangerous.

In addition, the composite reinforced hose 1 is used in the transmission of high-pressure hydraulic pressure and the transportation of high-pressure fluid.
Tension and deformation are repeatedly applied to the aramid cord 3. In particular, if the aramid cords 3 of the reinforcing layer 5 are subjected to tension and deformation repeatedly and continuously for a long time under high-pressure hydraulic pressure, the aramid cords 3 of the reinforcing layer 5 may peel off or the aramid cords 3 may break.
There are also problems in that pressure resistance, fatigue life, and bending fatigue resistance are insufficient.

Therefore, the present invention has developed a composite reinforced cord by combining twisted cords constituting each reinforcing layer with raw fibers having a specific number of twists, a specific cord orientation direction, and a specific tensile modulus. Less twisting and deformation,
The purpose of the present invention is to provide a composite reinforced hose with improved pressure resistance, fatigue life, and bending fatigue resistance.

(Means for Solving the Problems) The present invention aims to improve the number of twists of the twisted cords of each reinforcing layer, the cord orientation angle, the tensile elastic modulus of the raw yarn, and the Various studies were conducted on the relationship between the distribution of reinforcing layers and hose torsion, deformation, pressure resistance, fatigue life, and bending fatigue resistance of the hose.

Generally, the cord orientation angle θ of the reinforcing fiber cords (hereinafter simply referred to as cords) of the reinforcing layer in a composite reinforced hose is:
It is preferable to maintain a constant angle θ determined by the following equation tan θ=41−, and it is said that the tensile force of the cord acts most effectively when a high-pressure fluid is pressurized. However, in a composite reinforced hose with a so-called spiral reinforcement structure in which the cord is spirally wound around the outside of the core tube, if the cord orientation angle θ of the cords in each reinforcement layer is kept constant, the hose will not twist or deform when pressurized. Occur. This twisting and deformation of the hose is due to the fact that the moment generated between the cords between the reinforcing layers during pressurization in the rotational direction about the axis of the hose cannot be balanced, that is, the hose becomes unbalanced. This moment balance is difficult to manifest as twist when the cord has a high tensile modulus, such as a steel wire. However, in the case of aramid fibers, they are used as twisted cords to improve fatigue life and bending fatigue resistance, and the tensile modulus of the aramid fiber cords is smaller than that of steel wires. For this reason, the balance of moments in the rotational direction of the reinforcing layer of the composite reinforced hose becomes unbalanced, causing twisting and deformation of the hose.

In the conventional composite reinforced hose shown in Fig. 3, the above-mentioned moment imbalance of the reinforcing layers is offset by changing the cord orientation angle θ of the cords of each reinforcing layer. . However, in such a case, twisting occurs because the moment is not sufficiently balanced, and the cord orientation angle deviates from the optimum angle, so the hose is pressurized with high-pressure oil pressure. Time,
The tensile strength of the cord is not effectively utilized, making it impossible to obtain sufficient pressure resistance and fatigue life.

The present inventor conducted further research on a composite reinforced hose that has sufficient performance without twisting or deformation while maintaining the cord orientation angle at an optimum angle.

In a composite reinforced hose, when pressurized, the innermost reinforcing layer receives the most stress due to pressure fluctuations.

For this reason, it is preferable that the innermost reinforcing layer is made of cords with a large number of twists and excellent fatigue resistance.

On the other hand, since a cord with a large number of twists has a low tensile modulus, the pressure resistance of the hose decreases. Therefore, the number of twists of the cord in the innermost reinforcing layer is the largest, and the number of twists in the cord is suitably decreased as you move from the inner to the outer reinforcing layer, thereby improving the pressure resistance and fatigue life of the hose. It has been found that it is possible to maintain high fatigue resistance performance and also maintain the balance of moments in each reinforcing layer.

The present inventor further conducted various studies and arrived at the present invention.

That is, the composite reinforced hose according to claim 1 of the present invention,
A core tube and a plurality of reinforcing fiber cords arranged approximately parallel to the outside of the core tube are wound helically, and the reinforcing fiber cords of adjacent layers are layered on the outside and the winding directions of the reinforcing fiber cords are inclined in opposite directions. In a composite reinforcing hose having an even number of reinforcing layers arranged as shown in FIG. It is characterized in that the average value of the number of twists of the reinforcing fiber cords is larger than the average value of the number of twists of the reinforcing fiber cords of the even-numbered reinforcing layers. Further, in the composite reinforced hose according to claim 2, the reinforcing layers are formed in pairs of two layers sequentially from the inside to the outside, and in each of the two layers, the number of twists of the reinforcing fiber cords constituting the inner reinforcing layer is The number of twists is greater than the number of twists of the reinforcing fiber cords constituting the outer reinforcing layer. Further, in the composite reinforced hose according to claim 3, the number of twists of the reinforcing fiber cords constituting the innermost reinforcing layer in the reinforcing layer is the largest among the number of twists of the reinforcing fiber cords constituting each reinforcing layer. Additionally, the reinforcing fiber cords are arranged so that the number of twists of the reinforcing fiber cords decreases sequentially as the reinforcing layer moves from the inner reinforcing layer to the outer reinforcing layer. The composite reinforced hose according to a fourth aspect of the present invention is characterized in that the reinforcing layer is composed of two or more types of yarns having different tensile moduli.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1.2 is a diagram showing Example 1 of the composite reinforced hose according to the present invention. In Fig. 1, reference numeral 11 denotes a composite reinforced hose, and the composite reinforced hose 11 has a core tube 12 made of nylon resin and two aramid fibers each having a thickness of 1,500 deniers twisted on the outside of the core tube 12 (so-called , single yarn size 1500 d/2 US E, 1.d
u Pont da Nemours & Co. (trade name: "Kevlar 29") Aramid cords 13, which are twisted reinforcing fiber cords, are arranged in parallel and spirally wound to form four reinforcing layers 15; It has an outer skin 16 made of polyurethane resin that covers the outside. A protective layer 17 made of woven polyester fiber is interposed between the outer skin 16 and the reinforcement N15. The four reinforcing layers 15 are layered one after another from the inside to the outside of the reinforcing layer 15, and when each layer is numbered sequentially from the inside to the outside, the first reinforcing layer 15
18, second reinforcing layer 15□8, third reinforcing layer 151. and a fourth reinforcing layer 1543 (representatively indicated by 15). Table 1.3.5 shows 1s, 2s, 3s,
It is shown in 4s.

Further, the winding direction of the aramid cord 13 between adjacent layers, that is, the cord direction C, is arranged to be inclined in opposite directions with respect to the circumferential line T parallel to the axis S of the core tube 12. The cord orientation angle θ between the cord direction C and the circumferential line T is 53° for each reinforcement N15.
They are almost the same at 56°, which is the optimum cord orientation angle. The number of aramid cords 13 in each reinforcing layer 15 is 15. 20 each in the order of ~154,
They are 22, 25 and 27. The number of twists of the aramid cords 13 of each reinforcing layer 15 is as shown in Table 1 and FIG.
Both the top twist and the bottom twist are the same, 35/10 cm
It is 35.30/30.25/25.20/20. That is, as described in claim 1, the average number of twists of the aramid cords 13 of the odd-numbered reinforcing layers 15 is (35+25)÷2.
, that is, 30 is the average value of the number of twists of the aramid cords 13 of the reinforcing layer 15 with an even number (30+20'')÷2, that is, 2
Greater than 5. If the number of twists of aramid cord 13 is large,
The tensile modulus E of the reinforcing layer 15 is small, and the bending fatigue resistance is excellent. For this reason, the composite reinforced hose 11 according to the present invention
Since the number of twists of the aramid cords 13 in each reinforcing layer 15 is arranged as described above, each reinforcing layer 15 is
The pan lath of the moment balance is maintained, the torsional deformation of the composite reinforced hose 11 is significantly reduced, and the pressure resistance and bending fatigue resistance are improved.

Further, as described in claim 2, the reinforcing layers 15 are formed in pairs of two layers sequentially from the inside to the outside, that is, the 1st, 2nd reinforcing layers 15.3.15! s for the first pair, 3.4 reinforcement layer 1
53! , 154. Let be the second pair. And 2 of each layer
In the layers, the number of twists of the aramid cords 13 constituting the inner reinforcing layer 15 is larger than the number of twists of the aramid cords 13 constituting the outer reinforcing layer 15. That is, 35 is greater than 30 and 25 is greater than 20. For this reason, each reinforcing layer 1
The tensile modulus of elasticity between 5 and 5 is preferably arranged, and the balance of pressure resistance is further suitably maintained.

Further, as described in claim 3, the innermost first reinforcing layer 151 within the reinforcing layer 7115. Aramid cord 13 comprising
Aramid cord 1 of which the number of twists is 35 constitutes each reinforcement N15
3 twist number, i.e. the maximum among 35.30.25.20 and from the inner reinforcing layer 15 to the outer reinforcing layer 15
The arrangement is such that the number of twists of the aramid cord 13 decreases as the number of twists increases. Therefore, the tensile modulus of each reinforcing layer 15 increases sequentially, and the force applied to each reinforcing layer when hydraulic pressure is applied is appropriately distributed. Therefore, the pressure resistance, fatigue life, and bending fatigue resistance of the composite reinforced hose 11 are further significantly improved.

Next, Examples 1 to 6 and Comparative Examples 1.2 were prepared, and the effects of the present invention were confirmed through tests, which will be described below.

Table 1.3.5 shows the number of twists of the aramid cords and the fiber materials used in each reinforcing layer of Examples 2 to 6 and Comparative Example 1.2. The configuration other than the above is the same as in the first embodiment.

(This page, margins below) Table 1 Table 2 The unit of numerical values in the table is angle (0).

Table 3 Table 4 Table 5 Table 6 The unit of numerical values in the table is angle (0).

In Examples 1 and 2, a single fiber material Kevlar 29 was used, and in Examples 3, 4, 5, and 6, two types of fiber materials Kevlar 29 and Kepra 49 were used. The yarn elastic modulus of Kevlar 29 and Kevlar 49 is 4, respectively.
00-700gf/denier and 700-1200
gf/denier. Moreover, in Example 4.5,
The number of twists of 6 indicates that two single yarns are aligned and twisted together six times in one direction. Comparative Examples 1 and 2 are cases in which the number of twists of the cords in each of the four reinforcing layers is the same; in Comparative Example 1, the number of twists is 30, and in Comparative Example 2, it is 20.

In the test, the composite reinforced hoses of Examples 1 to 6 and Comparative Example 1 were subjected to a torsion test and a bending fatigue test.

The torsion test was carried out by holding a 1m long composite reinforced hose horizontally, sealing one end, fixing a spirit level horizontally above the hose, and applying hydraulic pressure from the other end to 100kgf/C111 to 700kg.
f/ci: Pressure increases and decreases every 100 kg f/ci. At this time, the twist angle around the axis of the composite reinforced hose was measured using a spirit level, and the average value was compared. The test results are shown in Table 2.6. The unit is angle (degrees).

In the bending fatigue test, a 1m long composite reinforced hose was held vertically, the upper end was sealed, and it was fixed to the top of an arm that could rotate at a 90° left and right angle using the center of the composite reinforced hose as a fulcrum. However, a constant load is applied to the lower end, and at the same time, it is pressurized with a hydraulic pressure of 700 kg f /C111 by a hydraulic pump. The arm was rotated to a left-right angle of 90° at a constant speed to repeatedly bend the composite reinforced hose, and the test was performed by counting the number of times until the composite reinforced hose broke. The test results are shown in Table 4.

As shown in Table 2.4.6, the test results for Examples 1 and 2 using a single fiber material Keppra 29 were as follows as compared to Comparative Example 1.
The torsion angle was significantly reduced during each pressurization, showing excellent results.

In addition, in Examples 3 to 5 using two types of fiber materials, Kevlar 29 and Kevlar 49, the twist angle was significantly reduced compared to Comparative Example 1, compared to the case where a single fiber material Kevlar 29 was used. Example 6 showed an even greater reduction than Example 2,
Showing excellent results.

In addition, in Example 1, the number of bending fractures was significantly increased compared to Comparative Example 2, and the bending fatigue resistance was significantly improved. Further, in Examples 1 to 5, the pressure resistance performance was also significantly improved compared to Comparative Example 1.2.

For reasons described later, the twisted yarn made of two twisted single yarns of 1500 d described as an example of the present invention is different from the twisted yarn of two single yarns having a diameter of 1500 d, even in the case of a composite reinforced hose reinforced with aramid twisted yarn with a different thickness By applying the structure according to claims 1 to 4 of the present invention, the pressure resistance performance and fatigue life of the hose can be improved. The reason for this is that the twist strength of the twisted yarn is expressed by the twist coefficient K shown in the following formula, K-TV "Here, K is the twist coefficient T is the number of twists/1nch D is the denier number For example, 1500 d single yarn The number of twists is 30/10 with two strands of
The strength of a twisted yarn of cm is the same as that of a twisted yarn of 24.5/10 cm when three strands of 1500 d single yarn are twisted.

The fatigue life of the twisted yarn and the tensile elastic modulus of the twisted yarn with respect to repeated loading and unloading of the tensile load of the twisted yarn depend on the twist coefficient K in the above formula.

Therefore, by converting the number of twists of the aramid twisted yarn in the example of the present invention and adopting aramid twisted yarn with a corresponding thickness and twist coefficient, the composite reinforced hose has less twisting and deformation, and has improved pressure resistance and resistance. Fatigue life can be significantly improved.

In addition, in Example 3.4.5.6 of the present invention, the reinforcing layer is
The case where each reinforcing layer is composed of yarns having a single tensile modulus of a composite reinforced hose made of two types of yarns having different tensile moduli has been introduced.

For example, in Example 6, the first reinforcing layer 15 in FIG.
+s is entirely composed of Kevlar 29, and the second reinforcing layer 15
z, are all composed of Kevlar 49, and the third reinforcing layer 15
All 3s are composed of Kevlar 29, and the fourth reinforcement Fif
15ns is entirely composed of Kevlar 49.

However, each reinforcing layer can be composed of yarns having two or more different tensile moduli by using any of the methods described in (1) to (3) below. That is, (1) Each reinforcing layer is composed of two or more types of reinforcing fiber cords each composed of yarns having different tensile moduli.

(2) The reinforcing fiber cords constituting each reinforcing layer are constructed by twisting together single yarns each made of fibers having different tensile moduli.

(3) The reinforcing fiber cords constituting each reinforcing layer are composed of single yarns formed by mixing fiber filaments having different tensile moduli.

(Effects) As explained above, according to claim 1 of the present invention, by setting the cords constituting each reinforcing layer to a specific number of twists and setting the cord orientation angle to an optimal angle, twisting and deformation can be reduced ( ,
It can significantly improve pressure resistance, fatigue life, and fatigue resistance. Moreover, according to claim 2, in addition to the above, the balance of pressure resistance of each reinforcing layer can be suitably maintained. Moreover, according to claim 3, in addition to the above, the balance of fatigue resistance is suitably maintained, and pressure resistance performance, fatigue life resistance, and bending fatigue resistance performance can be further suitably maintained. Also, claim 4
According to, in addition to the above, by suitably combining cords made of raw fibers having a specific tensile modulus,
The composite reinforced hose has less twisting and deformation, and has improved pressure resistance, fatigue life, and bending fatigue resistance.
It can be significantly improved.

[Brief explanation of drawings]

1.2 are diagrams showing one embodiment of the composite reinforced hose according to the present invention, FIG. 1 is a partially removed perspective view, and FIG. 2 is an enlarged view of the main parts thereof. FIG. 3 is a partially removed perspective view of a conventional composite reinforced hose. 11...Composite reinforced hose, 12...Core tube, 13...Aramid cord (reinforced fiber cord),
15.15+s 15zs 153s 15as
... Reinforcement layer, 16 ... Outer skin. Figure 1 Figure 2

Claims (4)

[Claims] (1) A core tube and a plurality of reinforcing fiber cords arranged approximately parallel to the outside of the core tube are wound spirally, and the reinforcing fiber cords in adjacent layers are layered on the outside and the winding directions are opposite to each other. In a composite reinforced hose having an even number of reinforcing layers arranged at an angle in the direction of A composite reinforced hose characterized in that the average number of twists of the reinforcing fiber cords in the reinforcing layer is larger than the average number of twists of the reinforcing fiber cords in even-numbered reinforcing layers. (2) Reinforcement in which the reinforcing layers are sequentially formed into pairs of two layers from the inside to the outside, and in the two layers of each pair, the number of twists of the reinforcing fiber cords that make up the inner reinforcing layer is the same as that of the outer reinforcing layer. The composite reinforced hose according to claim 1, characterized in that the number of twists is greater than that of the fiber cord. (3) The number of twists of the reinforcing fiber cords constituting the innermost reinforcing layer in the reinforcing layer is the largest among the number of twists of the reinforcing fiber cords constituting each reinforcing layer, and 3. The composite reinforced hose according to claim 1, wherein the reinforcing fiber cords are arranged such that the number of twists of the reinforcing fiber cords decreases sequentially as the reinforcing fiber cords move to the reinforcing layer. (4) Claim 1, wherein the reinforcing layer is composed of two or more types of yarns having different tensile moduli.
Composite reinforced hose according to 2 or 3.