Composite cable

Abstract

To provide a composite cable that exhibits relatively superior lightweight property and relatively superior flexibility, while having enhanced impact resistance.SOLUTION: A composite cable 1 is provided with a sheath 5, a plastic optical fiber 21 arranged on the inside of the sheath 5, an optical fiber coating layer 22 covering the plastic optical fiber 21 and disposed between the sheath 5 and the plastic optical fiber 21, and a power supply line 4 disposed between the sheath 5 and the optical fiber coating layer 22, in which the thickness (s) of the sheath 5 and the thickness (f) of the optical fiber coating layer 22 fulfill f≥0.65 s.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a composite cable. [Background technology]

[0002] Composite cables have been known in the past. Composite cables include, for example, power lines, optical cables, and electric signal cables. Optical cables include, for example, optical fibers. Known optical fibers include, for example, glass optical fibers (GOF), whose cores and / or claddings are made of glass. More specifically, known optical fibers include all-glass fibers (AGF), whose cores and claddings are made of glass, and hard plastic clad fibers (HPCF), whose cores are made of glass and whose claddings are made of resin. The optical fibers are, for example, covered with a coating layer and arranged inside an outer jacket (sheath) (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2016-076377 Summary of the Invention [Problem to be solved by the invention]

[0004] On the other hand, the use of plastic optical fiber (POF), whose core and cladding are made of resin, is being considered as an optical fiber. Plastic optical fiber (POF) is relatively light and flexible, and therefore has relatively good handling properties.

[0005] On the other hand, the impact resistance of plastic optical fibers can be relatively low. However, if the outer sheath is designed to be thicker in order to improve the impact resistance of plastic optical fibers, the lightness and flexibility of the plastic optical fiber (POF) can be reduced.

[0006] The present invention is a composite cable that has relatively good light weight, relatively good flexibility, and improved impact resistance. [Means for solving the problem]

[0007] The present invention [1] includes a composite cable comprising a sheath, a plastic optical fiber arranged inside the sheath, an optical fiber coating material arranged between the sheath and the plastic optical fiber and coating the plastic optical fiber, and a power line arranged between the sheath and the optical fiber coating material, wherein a thickness s of the sheath and a thickness f of the optical fiber coating material satisfy the following formula (1): f≧0.65s (1)

[0008] In the above composite cable, the sheath thickness s and the optical fiber coating thickness f satisfy the above formula (2). That is, in the above composite cable, the optical fiber coating thickness f is relatively thick. Therefore, the impact resistance of the composite cable is improved. Also, in the above composite cable, the sheath thickness s is relatively thin. Therefore, the composite cable has relatively excellent lightness and flexibility.

[0009] The present invention [2] includes the composite cable according to the above [1], in which the thickness s of the sheath and the thickness f of the optical fiber coating material satisfy the following formula (1): f≧s (2)

[0010] In the above composite cable, the sheath thickness s and the optical fiber coating thickness f satisfy the above formula (2). That is, in the above composite cable, the optical fiber coating thickness f is comparatively thicker. Therefore, the impact resistance of the composite cable is further improved. Also, in the above composite cable, the sheath thickness s is comparatively thinner. Therefore, the composite cable has comparatively superior lightness and flexibility.

[0011] The present invention [3] includes the composite cable according to the above [1] or [2], further comprising a first tensile strength fiber disposed between the sheath and the optical fiber coating material, and in a cross section perpendicular to the longitudinal direction of the composite cable, the proportion of the total cross-sectional area of ​​the first tensile strength fiber to the cross-sectional area of ​​the composite cable is 5% or less.

[0012] In the above composite cable, the amount of the first tensile strength fibers does not contribute significantly to impact resistance. Therefore, the above composite cable is designed to have a relatively small amount of the first tensile strength fibers. As a result, the above composite cable can reduce costs while maintaining impact resistance.

[0013] The present invention [4] includes the composite cable described in [3] above, further comprising second tensile strength fibers arranged between the optical fiber coating material and the plastic optical fiber, and in a cross section perpendicular to the longitudinal direction of the composite cable, the proportion of the total cross-sectional area of ​​the second tensile strength fibers to the cross-sectional area of ​​the composite cable is greater than the proportion of the total cross-sectional area of ​​the first tensile strength fibers to the cross-sectional area of ​​the composite cable.

[0014] In the above composite cable, the amount of the second tensile strength fibers contributes relatively greatly to impact resistance. Therefore, the above composite cable is designed to have a relatively large amount of the second tensile strength fibers. As a result, the impact resistance of the above composite cable is further improved.

[0015] The present invention [5] includes the composite cable described in [4] above, in which, in a cross section along a direction perpendicular to the longitudinal direction of the composite cable, the proportion of the cross-sectional area of ​​the optical fiber coating material to the cross-sectional area of ​​the composite cable is 5% or more and 20% or less.

[0016] In the above composite cable, the proportion of the cross-sectional area of ​​the optical fiber coating material contributes relatively significantly to impact resistance. Therefore, the above composite cable is designed so that the proportion of the cross-sectional area of ​​the optical fiber coating material is relatively large. As a result, the impact resistance of the above composite cable is further improved.

[0017] The present invention [6] includes the composite cable according to the above [1], wherein the tensile storage modulus E'(s) of the sheath at 26°C is 100 MPa or less.

[0018] The present invention [7] includes the composite cable according to the above [6], wherein the tensile storage modulus E'(s) of the sheath at 26°C is 20 MPa or more and 85 MPa or less.

[0019] In the composite cable, the tensile storage modulus E'(s) of the sheath is designed to be relatively small, which further improves the impact resistance of the composite cable.

[0020] The present invention [8] includes the composite cable according to the above [6] or [7], wherein the tensile storage modulus E'(f) of the optical fiber coating material at 26°C is 200 MPa or more.

[0021] In the above composite cable, the tensile storage modulus E'(f) of the optical fiber coating material is designed to be relatively large, which further improves the impact resistance of the above composite cable.

[0022] The present invention [9] includes the composite cable according to any one of the above [6] to [8], wherein the tensile storage modulus E'(s) of the sheath at 26°C is smaller than the tensile storage modulus E'(f) of the optical fiber coating material at 26°C, and the difference between the tensile storage modulus E'(s) of the sheath at 26°C and the tensile storage modulus E'(f) of the optical fiber coating material at 26°C is 300 MPa or more.

[0023] The composite cable is designed to have a relatively large difference between the tensile storage modulus E'(s) of the sheath and the tensile storage modulus E'(f) of the optical fiber coating material, which results in the composite cable being relatively lightweight and flexible, and having further improved impact resistance.

[0024] The present invention

[10] includes the composite cable according to any one of the above [1] to [9], wherein a plurality of the plastic optical fibers are arranged inside one of the optical fiber coating materials.

[0025] In the above composite cable, when a plurality of plastic optical fibers are arranged inside one optical fiber coating material, the plastic optical fibers may be damaged due to collisions between the plurality of plastic optical fibers.

[0026] In contrast, in the above composite cable, the thickness s of the sheath and the thickness f of the optical fiber coating material satisfy the above formula (1). In other words, the thickness f of the optical fiber coating material is relatively thick. Therefore, even when multiple plastic optical fibers are placed inside a single optical fiber coating material, impact resistance is improved and collisions between the multiple plastic optical fibers are suppressed.

[0027] The present invention

[11] includes the composite cable according to any one of the above [1] to

[10] , wherein the sheath contains polyurethane and the optical fiber coating material contains polyethylene and magnesium hydroxide.

[0028] In the composite cable, the sheath contains polyurethane, and the optical fiber coating material contains polyethylene and magnesium hydroxide. In this case, the sheath and the optical fiber coating material each have excellent lightness, flexibility, and impact absorption. In other words, the composite cable has relatively excellent lightness and flexibility, and further improved impact resistance.

[0029] The present invention

[12] includes the composite cable according to any one of the above [1] to

[11] , further comprising a second tensile strength fiber disposed between the optical fiber coating material and the plastic optical fiber, and the amount of the second tensile strength fiber is 0.2 g / m or more.

[0030] In the above composite cable, the amount of the second tensile strength fibers contributes relatively greatly to impact resistance. Therefore, the above composite cable is designed to have a relatively large amount of the second tensile strength fibers. As a result, the impact resistance of the above composite cable is further improved.

[0031] The present invention

[13] includes a composite cable comprising a sheath, a plastic optical fiber arranged inside the sheath, an optical fiber coating material arranged between the sheath and the plastic optical fiber and coating the plastic optical fiber, a power line arranged between the sheath and the optical fiber coating material, a first tensile strength fiber arranged between the sheath and the optical fiber coating material, and a second tensile strength fiber arranged between the optical fiber coating material and the plastic optical fiber, wherein in a cross section perpendicular to the longitudinal direction of the composite cable, the proportion of the total cross-sectional area of ​​the second tensile strength fibers to the cross-sectional area of ​​the composite cable is greater than the proportion of the total cross-sectional area of ​​the first tensile strength fibers to the cross-sectional area of ​​the composite cable.

[0032] In the above composite cable, the amount of the second tensile strength fibers contributes relatively greatly to impact resistance. Therefore, the above composite cable is designed to have a relatively large amount of the second tensile strength fibers. As a result, the above composite cable has further improved impact resistance. In addition, the above composite cable has relatively excellent lightness and relatively excellent flexibility.

[0033] The present invention

[14] includes the composite cable according to the above

[13] , in which the amount of the second tensile strength fibers is 0.2 g / m or more.

[0034] In the above composite cable, the amount of the second tensile strength fibers contributes relatively greatly to impact resistance. Therefore, the above composite cable is designed to have a relatively large amount of the second tensile strength fibers. As a result, the impact resistance of the above composite cable is further improved.

[0035] The present invention

[15] includes a composite cable comprising a sheath, a plastic optical fiber arranged inside the sheath, an optical fiber coating material arranged between the sheath and the plastic optical fiber and covering the plastic optical fiber, and a power line arranged between the sheath and the optical fiber coating material, wherein the thickness f of the optical fiber coating material is 35 mm or more.

[0036] In the above composite cable, the thickness f of the optical fiber coating material is equal to or greater than a predetermined value. That is, the thickness f of the optical fiber coating material is relatively large. Therefore, the impact resistance of the composite cable is improved.

[0037] The present invention

[16] includes the composite cable according to the above

[15] , further comprising a second tensile strength fiber disposed between the optical fiber coating material and the plastic optical fiber, wherein the amount of the second tensile strength fiber is 0.2 g / m or more.

[0038] In the above composite cable, the amount of the second tensile strength fibers contributes relatively greatly to impact resistance. Therefore, the above composite cable is designed to have a relatively large amount of the second tensile strength fibers. As a result, the impact resistance of the above composite cable is further improved. [Effects of the Invention]

[0039] The composite cable of the present invention has relatively excellent lightness and flexibility, and also has improved impact resistance. [Brief explanation of the drawings]

[0040] [Figure 1] FIG. 1 is a cross-sectional view of one embodiment of the composite cable of the present invention. [Figure 2] FIG. 2 is a graph showing the relationship between the stress value and the time elapsed from the start of the fall of the weight in Examples 1 to 3 and Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0041] 1. One embodiment Referring to FIG. 1, one embodiment of the composite cable will be described.

[0042] (1) Composite cable (1-1) Overall structure The composite cable 1 has a substantially circular shape in cross section, which is taken along a direction perpendicular to the longitudinal direction (the same applies hereinafter).

[0043] The composite cable 1 includes a sheath 5, a first tensile strength fiber 6, an optical cable 2, an electric signal cable 3, and a power line 4. Each of these will be described in detail below.

[0044] (1-2) Sheath The sheath 5 is the outermost layer of the composite cable 1. The sheath 5 has a substantially cylindrical shape. That is, the sheath 5 has a substantially annular shape in a cross-sectional view.

[0045] The sheath 5 is formed from a known material by a known method. Examples of the material for the sheath 5 include resins. Examples of the resin include polyvinyl chloride and polyurethane. These can be used alone or in combination of two or more. Examples of the material for the sheath 5 include polyvinyl chloride and polyurethane, and more preferably polyurethane. In other words, the sheath 5 preferably includes polyvinyl chloride and / or polyurethane, and more preferably includes polyurethane.

[0046] As will be described in more detail below, the material of the sheath 5 is preferably selected based on its storage modulus.

[0047] There is no particular limitation on the number of sheaths 5. For example, one composite cable 1 may have one sheath 5.

[0048] The sheath 5 has a predetermined thickness s. The thickness s is the shortest distance between the outer peripheral surface and the inner peripheral surface in a cross-sectional view. For example, if the sheath 5 has a circular ring shape in a cross-sectional view, the thickness s is the radial length in the cross-sectional view. The same applies to the thickness f described below.

[0049] The thickness s of the sheath 5 is designed based on the formula (1) described later.

[0050] The thickness s of the sheath 5 is, for example, 0.37 mm or more, preferably 0.40 mm or more, and more preferably 0.42 mm or more. The thickness s of the sheath 5 is, for example, 1.50 mm or less, preferably 1.00 mm or less, and more preferably 0.50 mm or less. That is, the thickness s of the sheath 5 is, for example, 0.30 mm or more and 1.50 mm or less, preferably 0.40 mm or more and 1.00 mm or less, and more preferably 0.42 mm or more and 0.50 mm or less.

[0051] The outer diameter of the sheath 5 is not particularly limited. For example, the outer diameter of the sheath 5 is, for example, 5.0 mm or more, preferably 5.2 mm or more, and more preferably 5.5 mm or more. The outer diameter of the sheath 5 is, for example, 7.0 mm or less, preferably 6.5 mm or less, and more preferably 6.0 mm or less. That is, the outer diameter of the sheath 5 is, for example, 5.0 mm or more and 7.0 mm or less, preferably 5.2 mm or more and 6.5 mm or less, and more preferably 5.5 mm or more and 6.0 mm or less.

[0052] The inner diameter of the sheath 5 is not particularly limited. For example, the inner diameter of the sheath 5 is, for example, 4.1 mm or more, preferably 4.3 mm or more, and more preferably 4.6 mm or more. The inner diameter of the sheath 5 is, for example, 6.1 mm or less, preferably 5.6 mm or less, and more preferably 5.1 mm or less. That is, the inner diameter of the sheath 5 is, for example, 4.1 mm or more and 6.1 mm or less, preferably 4.3 mm or more and 5.6 mm or less, and more preferably 4.6 mm or more and 5.1 mm or less.

[0053] The sheath 5 is disposed on the outermost side of the composite cable 1. The sheath 5 covers (in other words, houses) the first tensile strength fiber 6, the optical cable 2, the electric signal cable 3, and the power line 4.

[0054] (1-3) First tensile strength fiber The first tensile strength fibers 6 are reinforcing materials that reinforce the optical cable 2. The first tensile strength fibers 6 have a substantially cylindrical shape. That is, the first tensile strength fibers 6 have a substantially circular shape in a cross-sectional view.

[0055] The first tensile strength fibers 6 are formed by a known method. For example, aramid resin can be used as the material for the first tensile strength fibers 6. These can be used alone or in combination of two or more types.

[0056] There is no particular limitation on the number of first tensile strength fibers 6. For example, the number of first tensile strength fibers 6 is plural. More specifically, the number of first tensile strength fibers 6 (unit: fibers) per composite cable 1 is, for example, 100 to 1000, preferably 200 to 600.

[0057] The first tensile strength fibers 6 are disposed inside the composite cable 1. That is, the first tensile strength fibers 6 are disposed inside the sheath 5 (in other words, inside the tube).

[0058] The first tensile strength fibers 6 are disposed on the outer side of the optical fiber coating material 22. In other words, the first tensile strength fibers 6 are disposed between the sheath 5 and the optical fiber coating material 22.

[0059] The thickness (here, this means the outer diameter) of the first tensile strength fibers 6 is not particularly limited. For example, the thickness (here, this means the outer diameter) of the first tensile strength fibers 6 is, for example, 0.05 mm or more, preferably 0.15 mm or more. The thickness (here, this means the outer diameter) of the first tensile strength fibers 6 is, for example, 0.50 mm or less, preferably 0.35 mm or less. In other words, the thickness (here, this means the outer diameter) of the first tensile strength fibers 6 is, for example, 0.05 mm or more and 0.50 mm or less, preferably 0.15 mm or more and 0.35 mm or less.

[0060] (1-4) Optical cable The optical cable 2 is an optical transmission component that transmits an optical signal in the composite cable 1. The optical cable 2 has a substantially cylindrical shape. That is, the optical cable 2 has a substantially circular shape in a cross-sectional view.

[0061] There is no particular limitation on the number of optical cables 2. For example, the number of optical cables 2 for one composite cable 1 is one.

[0062] The optical cable 2 includes an optical fiber coating material 22, a plastic optical fiber 21, and a second tensile strength fiber 23.

[0063] In other words, the composite cable 1 includes an optical fiber coating material 22, a plastic optical fiber 21, and a second tensile strength fiber 23.

[0064] [Optical fiber coating material] The optical fiber coating material 22 is the outermost layer of the optical cable 2. The optical fiber coating material 22 has a substantially cylindrical shape. That is, the optical fiber coating material 22 has a substantially annular shape in a cross-sectional view.

[0065] The optical fiber coating material 22 is formed from known materials by known methods. Examples of materials for the optical fiber coating material 22 include resins. Examples of resins include acrylic resins, epoxy resins, polyimide resins, and ionomer resins. These can be used alone or in combination of two or more. A preferred material for the optical fiber coating material 22 is ionomer resin.

[0066] The ionomer resin is not particularly limited, but examples thereof include ethylene-based ionomers and styrene-based ionomers, with ethylene-based ionomers being preferred. The ethylene-based ionomer contains, for example, polyethylene and a metal ion. Examples of the metal include sodium, magnesium, and zinc, with magnesium being preferred. A particularly preferred ionomer resin is an ethylene-based ionomer containing polyethylene and magnesium hydroxide. In other words, the optical fiber coating material 22 preferably contains polyethylene and magnesium hydroxide.

[0067] As will be described in more detail below, the material of the optical fiber coating 22 is preferably selected based on its storage modulus.

[0068] There is no particular limitation on the number of optical fiber coating materials 22. For example, the number of optical fiber coating materials 22 for one optical cable 2 is one.

[0069] The optical fiber coating material 22 has a predetermined thickness f. The thickness f of the optical fiber coating material 22 is designed based on the formula (1) described below.

[0070] The thickness f of the optical fiber coating material 22 is, for example, 0.26 mm or more, preferably 0.35 mm or more, more preferably 0.45 mm or more, and even more preferably 0.50 mm or more. The thickness f of the optical fiber coating material 22 is, for example, 1.10 mm or less, preferably 0.80 mm or less, more preferably 0.70 mm or less, and even more preferably 0.60 mm or less. That is, the thickness f of the optical fiber coating material 22 is, for example, 0.26 mm or more and 1.10 mm or less, preferably 0.35 mm or more and 0.80 mm or less, more preferably 0.45 mm or more and 0.70 mm or less, and even more preferably 0.50 mm or more and 0.60 mm or less.

[0071] The outer diameter of the optical fiber coating material 22 is not particularly limited. For example, the outer diameter of the optical fiber coating material 22 is, for example, 1.7 mm or more, preferably 1.9 mm or more, and more preferably 2.1 mm or more. The outer diameter of the optical fiber coating material 22 is, for example, 5 mm or less, preferably 4 mm or less, and more preferably 3 mm or less. That is, the outer diameter of the optical fiber coating material 22 is, for example, 1.7 mm or more and 5 mm or less, preferably 1.9 mm or more and 4 mm or less, and more preferably 2.1 mm or more and 3 mm or less.

[0072] The inner diameter of the optical fiber coating material 22 is not particularly limited. For example, the inner diameter of the optical fiber coating material 22 is, for example, 1.2 mm or more, preferably 1.4 mm or more, and more preferably 1.6 mm or more. The inner diameter of the optical fiber coating material 22 is, for example, 4.5 mm or less, preferably 4.0 mm or less, and more preferably 3.5 mm or less. That is, the inner diameter of the optical fiber coating material 22 is, for example, 1.2 mm or more and 4.5 mm or less, preferably 1.4 mm or more and 4.0 mm or less, and more preferably 1.6 mm or more and 3.5 mm or less.

[0073] The optical fiber coating material 22 is disposed on the outermost side of the optical cable 2. The optical fiber coating material 22 is disposed inside the sheath 5 (in other words, inside the tube). In other words, the optical fiber coating material 22 is disposed between the sheath 5 and the plastic optical fiber 21. The optical fiber coating material 22 coats the plastic optical fiber 21. The optical fiber coating material 22 also coats the second tensile strength fiber 23.

[0074] [Plastic optical fiber] The plastic optical fiber 21 transmits an optical signal in the optical cable 2. The plastic optical fiber 21 has a substantially cylindrical shape. That is, the plastic optical fiber 21 has a substantially circular shape in a cross-sectional view.

[0075] The plastic optical fiber 21 has a known configuration. Specifically, the plastic optical fiber 21 includes, for example, a core (not shown), a cladding (not shown), and an overcladding (not shown) arranged in this order radially outward. The plastic optical fiber 21 is also flexible.

[0076] The plastic optical fiber 21 is formed from a known material by a known method. Examples of the material for the plastic optical fiber 21 include resin. Examples of the resin include acrylic resin and epoxy resin. These can be used alone or in combination of two or more types.

[0077] The number of plastic optical fibers 21 is not particularly limited. For example, the number of plastic optical fibers 21 is plural. More specifically, the number of plastic optical fibers 21 in one optical cable 2 is, for example, 2 or more and 8 or less, preferably 4 or more and 6 or less.

[0078] The thickness (here, this means the outer diameter) of the plastic optical fiber 21 is not particularly limited. The thickness (here, this means the outer diameter) of the plastic optical fiber 21 is, for example, 0.05 mm or more, preferably 0.15 mm or more. The thickness (here, this means the outer diameter) of the plastic optical fiber 21 is, for example, 0.50 mm or less, preferably 0.35 mm or less. In other words, the thickness (here, this means the outer diameter) of the plastic optical fiber 21 is, for example, 0.05 mm or more and 0.50 mm or less, preferably 0.15 mm or more and 0.35 mm or less.

[0079] The plastic optical fiber 21 is disposed inside the composite cable 1. In other words, the plastic optical fiber 21 is disposed inside the sheath 5 (in other words, inside the tube).

[0080] Moreover, the plastic optical fibers 21 are arranged inside the optical fiber coating material 22 (in other words, inside a tube). Preferably, all of the multiple plastic optical fibers 21 are arranged inside one optical fiber coating material 22. In other words, all of the plastic optical fibers 21 are collectively coated with one optical fiber coating material 22.

[0081] [Second tensile strength fiber] The second tensile strength fibers 23 are reinforcing materials that reinforce the optical cable 2. The second tensile strength fibers 23 have a substantially cylindrical shape. That is, the second tensile strength fibers 23 have a substantially circular shape in a cross-sectional view.

[0082] The second tensile strength fibers 23 are formed from known materials by known methods. Examples of materials for the second tensile strength fibers 23 include aramid resin. These can be used alone or in combination of two or more types.

[0083] There is no particular limitation on the number of second tensile strength fibers 23. The number (unit: pieces) of second tensile strength fibers 23 is, for example, a plurality. More specifically, the number of second tensile strength fibers 23 per optical cable 2 is, for example, 100 to 1000, preferably 200 to 600.

[0084] Furthermore, in one composite cable 1, the number of second tensile strength fibers 23 (unit: pieces) is preferably greater than the number of first tensile strength fibers 6. The difference between the number of second tensile strength fibers 23 and the number of first tensile strength fibers 6 is, for example, 10 or more and 300 or less, preferably 50 or more and 200 or less.

[0085] The thickness (here, this means the outer diameter) of the second tensile strength fibers 23 is not particularly limited. For example, the thickness (here, this means the outer diameter) of the second tensile strength fibers 23 is, for example, 0.05 mm or more, preferably 0.15 mm or more. The thickness (here, this means the outer diameter) of the second tensile strength fibers 23 is, for example, 0.50 mm or less, preferably 0.35 mm or less. In other words, the thickness (here, this means the outer diameter) of the second tensile strength fibers 23 is, for example, 0.05 mm or more and 0.50 mm or less, preferably 0.15 mm or more and 0.35 mm or less.

[0086] The second tensile strength fibers 23 are disposed inside the composite cable 1. In other words, the second tensile strength fibers 23 are disposed inside the sheath 5 (in other words, inside the tube).

[0087] The second tensile strength fibers 23 are disposed inside the optical fiber coating material 22 (in other words, inside the tube). That is, the plastic optical fiber 21 and the second tensile strength fibers 23 are disposed side by side inside the optical fiber coating material 22. In other words, the second tensile strength fibers 23 are disposed between the optical fiber coating material 22 and the plastic optical fiber 21.

[0088] [Optical cable placement] The optical cable 2 is manufactured by a known method and is disposed inside the composite cable 1. More specifically, the optical cable 2 is disposed inside the sheath 5 (in other words, inside a tube). The optical cable 2 is also disposed outside the shielding member 32, which will be described later. That is, the optical cable 2 is disposed between the sheath 5 and the electric signal cable 3. In other words, the optical cable 2 and the electric signal cable 3 are disposed side by side inside the sheath 5.

[0089] The thickness (here, this means the outer diameter) of the optical cable 2 is not particularly limited. For example, the thickness (here, this means the outer diameter) of the optical cable 2 is, for example, 5.0 mm or more, preferably 5.2 mm or more, and more preferably 5.5 mm or more. The thickness (here, this means the outer diameter) of the optical cable 2 is, for example, 7.0 mm or less, preferably 6.5 mm or less, and more preferably 6.0 mm or less. In other words, the thickness (here, this means the outer diameter) of the optical cable 2 is, for example, 5.00 mm or more and 7.0 mm or less, preferably 5.20 mm or more and 6.5 mm or less, and more preferably 5.50 mm or more and 6.0 mm or less.

[0090] (1-5) Electrical signal cable The electric signal cable 3 is an electric signal transmission component that transmits electric signals in the composite cable 1. The electric signal cable 3 has a substantially cylindrical or elliptical cylindrical shape. That is, the electric signal cable 3 has a substantially circular or elliptical shape in a cross-sectional view.

[0091] There is no particular limitation on the number of electric signal cables 3. For example, the number of electric signal cables 3 for one composite cable 1 is one.

[0092] The electric signal cable 3 includes, for example, a shielding member 32 and a pair of differential wirings 31 covered by the shielding member 32.

[0093] [Shielded cord] The shielding member 32 is the outermost layer of the electric signal cable 3. The shielding member 32 is an insulating member that bundles the pair of differential wiring lines 31. The shielding member 32 has a substantially cylindrical shape or a substantially elliptical cylindrical shape. That is, the shielding member 32 has a substantially circular ring shape or a substantially elliptical ring shape in a cross-sectional view.

[0094] The shielding member 32 is formed from known materials by known methods. Examples of materials for the shielding member 32 include resins and foams thereof. Examples of resins include polyester resins, polyolefin resins, polyimide resins, and rubber. These can be used alone or in combination of two or more types.

[0095] There is no particular limitation on the number of shielding members 32. For example, there is one shielding member 32 for one electric signal cable 3. There is no particular limitation on the thickness of the shielding member 32, and it is set appropriately depending on the purpose and application.

[0096] The shielding member 32 is disposed on the outermost side of the electric signal cable 3. The shielding member 32 is disposed inside the sheath 5 (in other words, inside the tube). In other words, the shielding member 32 is disposed between the sheath 5 and the pair of differential wiring lines 31. The shielding member 32 covers (in other words, houses) the pair of differential wiring lines 31.

[0097] [Differential wiring] The pair of differential wiring lines 31 transmits an electric signal in the electric signal cable 3. More specifically, the pair of differential wiring lines 31 includes a first wiring line 31A and a second wiring line 31B. The first wiring line 31A and the second wiring line 31B have the same configuration. Each of the pair of differential wiring lines 31 has a substantially cylindrical shape. That is, each of the pair of differential wiring lines 31 has a substantially circular shape in a cross-sectional view.

[0098] The pair of differential wiring lines 31 is formed from known materials by known methods. More specifically, each of the pair of differential wiring lines 31 includes a core wire 310 and a coating material 311 that covers the core wire 310, arranged in this order from the inside to the outside in the radial direction. Examples of materials for the core wire 310 include known metals (described later). Examples of materials for the coating material 311 include the above-mentioned resins. These materials can be used alone or in combination of two or more types.

[0099] There is no particular limitation on the number of pairs of differential wiring 31. The number of pairs of differential wiring 31 is, for example, one for one electric signal cable 3. That is, the number of first wirings 31A is, for example, one for one electric signal cable 3. Furthermore, the number of second wirings 31B is, for example, one for one electric signal cable 3.

[0100] The thickness (here, this means the outer diameter) of the first wiring 31A and the thickness (here, this means the outer diameter) of the second wiring 31B are not particularly limited and are set appropriately depending on the purpose and application.

[0101] The pair of differential wires 31 is arranged inside the composite cable 1. That is, the pair of differential wires 31 is arranged inside the sheath 5 (in other words, inside the tube).

[0102] Moreover, the pair of differential wiring lines 31 is arranged inside the shielding member 32 (in other words, inside the cylinder). Preferably, each of the pair of differential wiring lines 31 is arranged inside one shielding member 32. In other words, the pair of differential wiring lines 31 is collectively covered by one shielding member 32.

[0103] [Layout of electrical signal cables] The electric signal cable 3 is manufactured by a known method and is disposed inside the composite cable 1. More specifically, the electric signal cable 3 is disposed inside the sheath 5 (in other words, inside the tube). The electric signal cable 3 is also disposed outside the optical fiber coating material 22. That is, the electric signal cable 3 is disposed between the sheath 5 and the optical fiber coating material 22. In other words, the optical cable 2 and the electric signal cable 3 are disposed side by side inside the sheath 5.

[0104] The thickness (here, this means the outer diameter) of the electric signal cable 3 is not particularly limited and is set appropriately depending on the purpose and application.

[0105] (1-6) Power line The power line 4 is a cable for supplying power and includes, for example, a power feed line 41. The power line 4 can also include a ground line 42 as needed.

[0106] [Feeder line] The power supply line 41 has a substantially cylindrical shape. That is, the power supply line 41 has a substantially circular shape in a cross-sectional view.

[0107] The power feeder 41 is formed from known materials by known methods. Examples of materials for the power feeder 41 include metals. Examples of metals include tin, copper, iron, silver, gold, aluminum, nickel, and alloys thereof. Examples of alloys include stainless steel and bronze. These can be used alone or in combination. If necessary, the power feeder 41 can be provided with a power feeder cover (not shown) that covers the metal.

[0108] The number of power feed lines 41 is not particularly limited. For example, there is one power feed line 41 for one power line 4. The outer diameter of the power feed line 41 is not particularly limited and may be set appropriately depending on the purpose and application.

[0109] [Ground wire] The ground line 42 has a substantially cylindrical shape. That is, the ground line 42 has a substantially circular shape in cross section.

[0110] The ground line 42 is formed of a known material by a known method, such as the above-mentioned metals. If necessary, the ground line 42 may be provided with a ground line cover (not shown) that covers the above-mentioned metals.

[0111] There is no particular limit to the number of ground wires 42. For example, there is one ground wire 42 for one power line 4. There is no particular limit to the thickness (here, this means the outer diameter) of the ground wire 42, and it is set appropriately depending on the purpose and application.

[0112] [Power line placement] The power line 4 is manufactured by a known method and is arranged inside the composite cable 1. More specifically, the power feed line 41 and the ground line 42 are arranged adjacent to each other. The power feed line 41 and the ground line 42 are arranged inside the composite cable 1. In other words, the power line 4 is arranged inside the sheath 5 (in other words, inside the tube).

[0113] Furthermore, the power line 4 (the power feed line 41 and the ground line 42) is disposed outside the optical fiber coating material 22. That is, the power line 4 (the power feed line 41 and the ground line 42) is disposed between the sheath 5 and the optical fiber coating material 22.

[0114] Furthermore, the power line 4 (the power feed line 41 and the ground line 42) is disposed outside the shielding member 32. That is, the power line 4 (the power feed line 41 and the ground line 42) is disposed between the sheath 5 and the shielding member 32.

[0115] In other words, the optical cable 2, the electric signal cable 3, and the power line 4 (the power feed line 41 and the ground line 42) are arranged side by side inside the sheath 5.

[0116] (1-7) Stranded cable Although not shown in detail, the optical cable 2, the electric signal cable 3, and the power line 4 may form a twisted cable. That is, the optical cable 2, the electric signal cable 3, and the power line 4 are twisted together to form a helical wire (spiral wire). The twist pitch is set appropriately depending on the purpose and application. However, they do not necessarily have to form a twisted cable.

[0117] 2. Composite cable manufacturing method There are no particular limitations on the method for manufacturing the composite cable 1. For example, first, an optical cable 2, an electric signal cable 3, and a power line 4 are prepared. Next, the optical cable 2, the electric signal cable 3, and the power line 4 are twisted together to form a twisted cable. After that, the twisted cable is surrounded by a sheath 5. In this manner, the composite cable 1 is manufactured.

[0118] 3. Physical Properties (3-1) Thickness ratio In the above composite cable 1, the thickness s of the sheath 5 and the thickness f of the optical fiber coating material 22 are designed to satisfy the following formula (1).

[0119] f≧0.65s (1)

[0120] Preferably, in the above composite cable 1, the thickness s of the sheath 5 and the thickness f of the optical fiber coating material 22 are designed to satisfy the following formula (2).

[0121] f≧0.7s (2)

[0122] More preferably, in the above composite cable 1, the thickness s of the sheath 5 and the thickness f of the optical fiber coating material 22 are designed to satisfy the following formula (3).

[0123] f≧s (3)

[0124] That is, the thickness f of the optical fiber coating material 22 is 0.65 times or more, preferably 0.7 times or more, more preferably 0.9 times or more, particularly preferably 1.0 times or more, and most preferably 1.15 times or more relative to the thickness s of the sheath 5. Furthermore, the thickness f of the optical fiber coating material 22 is usually 5.0 times or less, preferably 3.0 times or less, and more preferably 1.5 times or less relative to the thickness s of the sheath 5. That is, the thickness f of the optical fiber coating material 22 is, for example, 0.65 to 5.0 times, preferably 0.7 to 5.0 times, more preferably 0.9 to 5.0 times, particularly preferably 1.0 to 3.0 times, and most preferably 1.15 to 1.5 times, relative to the thickness s of the sheath 5.

[0125] More specifically, when the thickness s of the sheath 5 is 0.42 mm, the thickness f of the optical fiber coating material 22 is, for example, 0.27 mm or more and 2.1 mm or less (0.65 times or more and 5.0 times or less), preferably 0.29 mm or more and 2.1 mm or less (0.7 times or more and 5.0 times or less), more preferably 0.37 mm or more and 2.1 mm or less (0.9 times or more and 5.0 times or less), particularly preferably 0.42 mm or more and 1.26 mm or less (1.0 times or more and 3.0 times or less), and most preferably 0.48 mm or more and 0.63 mm or less (1.15 times or more and 1.5 times or less).

[0126] (3-2) Area ratio [Total cross-sectional area of ​​first tensile strength fiber / cross-sectional area of ​​composite cable] In the above composite cable, the content of the first tensile strength fibers 6 (outer fibers of the optical cable) is preferably designed based on the area ratio in a cross-sectional view.

[0127] More specifically, the content of the first tensile strength fibers 6 is preferably adjusted so that the ratio of the cross-sectional area of ​​the composite cable 1 to the total cross-sectional area of ​​the first tensile strength fibers 6 is a predetermined value.

[0128] The cross-sectional area of ​​the composite cable 1 is the area of ​​the portion surrounded by the outer edge of the sheath 5. Even if there is a gap in the cross section of the composite cable 1, the cross-sectional area of ​​the composite cable 1 includes the cross-sectional area of ​​the gap (the same applies below).

[0129] The total cross-sectional area of ​​the first tensile strength fibers 6 is the sum of the cross-sectional areas of the plurality of first tensile strength fibers 6 (the same applies below).

[0130] For example, from the viewpoint of impact resistance, the lower limit of the proportion of the total cross-sectional area of ​​the first tensile strength fibers 6 in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1 is, for example, 0.37% or more, preferably 0.40% or more, and more preferably 0.45% or more of the cross-sectional area of ​​the composite cable 1.

[0131] Furthermore, from the viewpoint of low cost, the upper limit of the proportion of the total cross-sectional area of ​​the first tensile strength fibers 6 in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1 is, for example, 10% or less, preferably 5% or less, and more preferably 1% or less, of the cross-sectional area of ​​the composite cable 1.

[0132] That is, from the viewpoint of impact resistance and low cost, in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1, the proportion of the total cross-sectional area of ​​the first tensile strength fibers 6 to the cross-sectional area of ​​the composite cable 1 is, for example, 0.37% or more and 10% or less, preferably 0.40% or more and 5% or less, and more preferably 0.45% or more and 1% or less.

[0133] In terms of mass, the content of the first tensile strength fibers 6 is adjusted based on the mass (g / m) per meter of the composite cable.

[0134] Specifically, from the viewpoint of impact resistance, the lower limit of the content of the first tensile strength fibers 6 is, for example, 0.05 g / m or more, preferably 0.13 g / m or more, more preferably 0.14 g / m or more, and even more preferably 1.5 g / m or more.

[0135] Furthermore, from the viewpoint of cost efficiency, the upper limit of the content of the first tensile strength fibers 6 is, for example, 15 g / m or less, preferably 10 g / m or less, more preferably 5.0 g / m or less, even more preferably 3.5 g / m or less, and particularly preferably 1.8 g / m or less.

[0136] That is, from the viewpoint of impact resistance and low cost, the content of the first tensile strength fibers 6 is, for example, 0.05 g / m or more and 15 g / m or less, preferably 0.13 g / m or more and 10 g / m or less, more preferably 0.14 g / m or more and 5.0 g / m or less, even more preferably 1.5 g / m or more and 3.5 g / m or less, and particularly preferably 1.5 g / m or more and 1.8 g / m or less.

[0137] [Total cross-sectional area of ​​second tensile strength fiber / cross-sectional area of ​​composite cable] In the above composite cable, the content of the second tensile strength fibers 23 (fibers in the optical cable) is preferably designed based on the area ratio in a cross-sectional view.

[0138] More specifically, the content of the second tensile strength fibers 23 is preferably adjusted so that the ratio of the cross-sectional area of ​​the composite cable 1 to the total cross-sectional area of ​​the second tensile strength fibers 23 is a predetermined value.

[0139] The total cross-sectional area of ​​the second tensile strength fibers 23 is the sum of the cross-sectional areas of the plurality of second tensile strength fibers 23 (the same applies below).

[0140] For example, from the viewpoint of impact resistance, the lower limit of the proportion of the total cross-sectional area of ​​the second tensile strength fibers 23 in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1 is, for example, 8.9% or more, preferably 10% or more, and more preferably 15% or more of the cross-sectional area of ​​the composite cable 1.

[0141] Furthermore, from the viewpoint of low cost, the upper limit of the proportion of the total cross-sectional area of ​​the second tensile strength fibers 23 in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1 is, for example, 30% or less, preferably 25% or less, and more preferably 20% or less, of the cross-sectional area of ​​the composite cable 1.

[0142] That is, from the viewpoint of impact resistance and low cost, in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1, the proportion of the total cross-sectional area of ​​the second tensile strength fibers 23 to the cross-sectional area of ​​the composite cable 1 is, for example, 8.9% or more and 30% or less, preferably 10% or more and 30% or less, more preferably 10% or more and 25% or less, and particularly preferably 15% or more and 20% or less.

[0143] In terms of mass, the content of the second tensile strength fibers 23 is adjusted based on the mass (g / m) per meter of the composite cable.

[0144] Specifically, from the viewpoint of impact resistance, the content of the second tensile strength fibers 23 is, for example, 0.18 g / m or more, preferably 0.20 g / m or more, more preferably 0.30 g / m or more, and even more preferably 0.50 g / m or more.

[0145] Furthermore, from the viewpoint of low cost, the content of the second tensile strength fibers 23 is, for example, 15 g / m or less, preferably 10 g / m or less, more preferably 5 g / m or less, even more preferably 2 g / m or less, and particularly preferably 1 g / m or less or 0.60 g / m or less.

[0146] That is, from the viewpoint of impact resistance and low cost, the content of the second tensile strength fibers 23 is, for example, 0.18 g / m or more and 15 g / m or less, preferably 0.20 g / m or more and 10 g / m or less, more preferably 0.30 g / m or more and 5 g / m or less, even more preferably 0.30 g / m or more and 0.60 g / m or less, and particularly preferably 0.50 g / m or more and 0.60 g / m or less.

[0147] [Ratio of total cross-sectional area of ​​second tensile strength fibers - Ratio of total cross-sectional area of ​​first tensile strength fibers] Preferably, in a cross section perpendicular to the longitudinal direction of the composite cable 1, the proportion of the total cross-sectional area of ​​the second tensile strength fibers 23 to the cross-sectional area of ​​the composite cable 1 is greater than the proportion of the total cross-sectional area of ​​the first tensile strength fibers 6 to the cross-sectional area of ​​the composite cable.

[0148] For example, in a cross section perpendicular to the longitudinal direction of the composite cable 1, the lower limit of the difference between the proportion of the total cross-sectional area of ​​the first tensile fibers 6 and the proportion of the total cross-sectional area of ​​the second tensile fibers 23 to the cross-sectional area of ​​the composite cable 1 (proportion of the total cross-sectional area of ​​the second tensile fibers - proportion of the total cross-sectional area of ​​the first tensile fibers) is, for example, 8.5% or more, preferably 9.6% or more, and more preferably 14.5% or more.

[0149] Furthermore, in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1, the upper limit of the difference between the proportion of the total cross-sectional area of ​​the first tensile strength fibers 6 and the proportion of the total cross-sectional area of ​​the second tensile strength fibers 23 to the cross-sectional area of ​​the composite cable 1 (proportion of the total cross-sectional area of ​​the second tensile strength fibers - proportion of the total cross-sectional area of ​​the first tensile strength fibers) is, for example, 30% or less, preferably 25% or less, and more preferably 20% or less.

[0150] That is, in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1, the difference between the proportion of the total cross-sectional area of ​​the first tensile strength fibers 6 and the proportion of the total cross-sectional area of ​​the second tensile strength fibers 23 to the cross-sectional area of ​​the composite cable 1 (proportion of the total cross-sectional area of ​​the second tensile strength fibers - proportion of the total cross-sectional area of ​​the first tensile strength fibers) is, for example, 8.5% or more and 30% or less, preferably 9.6% or more and 25% or less.

[0151] [Cross-sectional area of ​​optical fiber coating material / cross-sectional area of ​​composite cable] In the above composite cable, the size of the optical fiber coating material 22 is preferably designed based on the area ratio in a cross-sectional view.

[0152] More specifically, the size of the optical fiber coating material 22 is preferably adjusted so that the ratio between the cross-sectional area of ​​the composite cable 1 and the cross-sectional area of ​​the optical fiber coating material 22 is a predetermined value.

[0153] The cross-sectional area of ​​the optical fiber coating material 22 is the cross-sectional area of ​​the thickness portion of the optical fiber coating material 22 (the same applies below).

[0154] For example, from the viewpoint of impact resistance, the lower limit of the proportion of the cross-sectional area of ​​the optical fiber coating material 22 in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1 is, for example, 4.8% or more, preferably 5% or more, and more preferably 10% or more of the cross-sectional area of ​​the composite cable 1.

[0155] Furthermore, from the viewpoint of low cost, the upper limit of the proportion of the cross-sectional area of ​​the optical fiber coating material 22 in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1 is, for example, 30% or less, preferably 20% or less, and more preferably 15% or less of the cross-sectional area of ​​the composite cable 1.

[0156] That is, from the viewpoint of impact resistance and low cost, in a cross section along a direction perpendicular to the longitudinal direction of the composite cable 1, the proportion of the cross-sectional area of ​​the optical fiber coating material 22 to the cross-sectional area of ​​the composite cable 1 is, for example, 4.8% or more and 30% or less, preferably 5% or more and 20% or less, and more preferably 10% or more and 15% or less.

[0157] (3-3) Storage modulus [Sheath storage modulus] In the above-described composite cable 1, the sheath 5 preferably has a predetermined storage modulus, that is, the material of the sheath 5 is preferably selected based on the storage modulus.

[0158] More specifically, from the viewpoints of impact resistance and handleability (particularly, lightness and flexibility), the lower limit of the tensile storage modulus E'(s) of the sheath 5 at 26°C is, for example, 5 MPa or more, preferably 10 MPa or more, and more preferably 20 MPa or more.

[0159] From the viewpoint of impact resistance and handleability, the upper limit of the tensile storage modulus E'(s) of the sheath 5 at 26°C is, for example, 115 MPa or less, preferably 100 MPa or less, and more preferably 85 MPa or less.

[0160] That is, from the viewpoint of impact resistance and ease of handling, the tensile storage modulus E'(s) of the sheath 5 at 26°C is, for example, 5 MPa or more and 115 MPa or less, preferably 10 MPa or more and 100 MPa or less, and more preferably 20 MPa or more and 85 MPa or less.

[0161] The conditions for measuring the tensile storage modulus E'(s) of the sheath 5 at 26°C conform to those in the examples described below.

[0162] [Storage modulus of optical fiber coating material] In the above-described composite cable 1, the optical fiber coating material 22 preferably has a predetermined storage modulus, that is, the material of the optical fiber coating material 22 is preferably selected based on the storage modulus.

[0163] More specifically, from the viewpoint of impact resistance and ease of handling, the lower limit of the tensile storage modulus E'(f) of the optical fiber coating material 22 at 26°C is, for example, 200 MPa or more, preferably 300 MPa or more, and more preferably 400 MPa or more.

[0164] From the viewpoint of impact resistance and ease of handling, the upper limit of the tensile storage modulus E'(f) of the optical fiber coating material 22 at 26°C is, for example, 800 MPa or less, preferably 700 MPa or less, and more preferably 600 MPa or less.

[0165] That is, from the viewpoint of impact resistance and ease of handling, the tensile storage modulus E'(s) of the optical fiber coating material 22 at 26°C is, for example, 200 MPa or more and 800 MPa or less, preferably 300 MPa or more and 700 MPa or less, and more preferably 400 MPa or more and 600 MPa or less.

[0166] The conditions for measuring the tensile storage modulus E'(s) of the optical fiber coating material 22 at 26°C conform to the conditions of the examples described later.

[0167] [Storage modulus of optical fiber coating material - Storage modulus of sheath] From the viewpoint of impact resistance and ease of handling, the tensile storage modulus E'(s) of the sheath 5 at 26°C is preferably smaller than the tensile storage modulus E'(f) of the optical fiber coating material 22 at 26°C.

[0168] More specifically, from the viewpoint of impact resistance and ease of handling, the lower limit of the difference between the tensile storage modulus E'(s) of the sheath 5 at 26°C and the tensile storage modulus E'(f) of the optical fiber coating material 22 at 26°C is, for example, 200 MPa or more, preferably 300 MPa or more, and more preferably 400 MPa or more.

[0169] From the viewpoints of impact resistance and ease of handling, the upper limit of the difference between the tensile storage modulus E'(s) of the sheath 5 at 26°C and the tensile storage modulus E'(f) of the optical fiber coating material 22 at 26°C is, for example, 800 MPa or less, preferably 700 MPa or less, and more preferably 600 MPa or less.

[0170] That is, from the viewpoint of impact resistance and ease of handling, the difference between the tensile storage modulus E'(s) of the sheath 5 at 26°C and the tensile storage modulus E'(f) of the optical fiber coating material 22 at 26°C is, for example, 200 MPa or more and 800 MPa or less, preferably 300 MPa or more and 700 MPa or less, and more preferably 400 MPa or more and 600 MPa or less.

[0171] 4. Effects In the composite cable 1, the thickness s of the sheath 5 and the thickness f of the optical fiber coating material 22 satisfy the above formula (1). That is, in the composite cable 1, the thickness f of the optical fiber coating material 22 is relatively thick. This improves the impact resistance of the composite cable 1. Furthermore, in the composite cable 1, the thickness s of the sheath 5 is relatively thin. This allows the composite cable 1 to have relatively excellent lightness and flexibility.

[0172] Preferably, in the composite cable 1, the thickness s of the sheath 5 and the thickness f of the optical fiber coating material 22 satisfy the above formula (2) or (3). That is, in the composite cable 1, the thickness f of the optical fiber coating material 22 is even thicker. This further improves the impact resistance of the composite cable 1. In addition, in the composite cable 1, the thickness s of the sheath is even thinner. This further improves the composite cable 1 in terms of lightness and flexibility.

[0173] In the composite cable 1, the amount of the first tensile strength fibers 6 does not contribute significantly to impact resistance. Therefore, the composite cable 1 is preferably designed so that the amount of the first tensile strength fibers 6 is relatively small. Therefore, the composite cable 1 can reduce costs while maintaining impact resistance.

[0174] In the composite cable 1, the amount of the second tensile strength fibers 23 makes a relatively large contribution to impact resistance. Therefore, the composite cable 1 is preferably designed to have a relatively large amount of the second tensile strength fibers 23. As a result, the impact resistance of the composite cable 1 is further improved.

[0175] Preferably, in the composite cable 1, the proportion of the cross-sectional area of ​​the optical fiber coating material 22 contributes relatively greatly to the impact resistance. Therefore, in the composite cable 1, the proportion of the cross-sectional area of ​​the optical fiber coating material 22 is designed to be relatively large. Therefore, the impact resistance of the composite cable 1 is further improved.

[0176] Preferably, the tensile storage modulus E'(f) of the optical fiber coating material is designed to be relatively large in the composite cable 1. Therefore, the impact resistance of the composite cable 1 is further improved.

[0177] Preferably, the composite cable 1 is designed so that there is a relatively large difference between the tensile storage modulus E'(s) of the sheath 5 and the tensile storage modulus E'(f) of the optical fiber coating material 22. As a result, the composite cable 1 has relatively excellent lightness and flexibility, and further improved impact resistance.

[0178] In the above-mentioned composite cable 1, when a plurality of plastic optical fibers 21 are arranged inside one optical fiber coating material 22, the plurality of plastic optical fibers 21 may collide with each other, resulting in damage to the plastic optical fibers 21.

[0179] In contrast, in the composite cable 1, the thickness s of the sheath 5 and the thickness f of the optical fiber coating material 22 preferably satisfy the above formula (1). In other words, the thickness f of the optical fiber coating material 22 is relatively thick. Therefore, even when multiple plastic optical fibers 21 are arranged inside one optical fiber coating material 22, impact resistance is improved and collisions between the multiple plastic optical fibers 21 are suppressed.

[0180] Preferably, in the composite cable 1, the sheath 5 contains polyurethane, and the optical fiber coating material 22 contains polyethylene and magnesium hydroxide. In this case, the sheath 5 and the optical fiber coating material 22 each have excellent lightness, flexibility, and impact absorption. In other words, the composite cable 1 has relatively excellent lightness and flexibility, and further improved impact resistance.

[0181] Furthermore, in the composite cable 1, the amount of the second tensile strength fibers contributes relatively greatly to impact resistance. Therefore, the composite cable 1 is designed to have a relatively large amount of the second tensile strength fibers. As a result, the impact resistance of the composite cable 1 is further improved. Furthermore, the composite cable 1 has relatively excellent lightness and flexibility.

[0182] Furthermore, in the composite cable 1, the thickness f of the optical fiber coating material 22 is equal to or greater than a predetermined value. That is, the thickness f of the optical fiber coating material 22 is relatively thick. Therefore, the impact resistance of the composite cable 1 is improved.

[0183] 5. Variations Although not shown, the composite cable 1 may further include a control wire. The number of control wires is not particularly limited. The number of control wires may be, for example, a plurality (e.g., two or more and eight or less). The control wire may include, for example, a control wire body formed from the above-mentioned metal and a cover formed from the above-mentioned resin that covers the body.

[0184] The control wire is surrounded by the sheath 5. In other words, the optical cable 2, the electric signal cable 3, the power wire 4, and the control wire are arranged side by side inside the sheath 5. The control wire can form a stranded cable together with the optical cable 2, the electric signal cable 3, and the power wire 4. Alternatively, they do not necessarily have to form a stranded cable.

[0185] Furthermore, in the composite cable 1, the number of each of the above-mentioned components (for example, the first tensile strength fiber 6, the optical cable 2, the plastic optical fiber 21, the optical fiber coating material 22, the second tensile strength fiber 23, the electrical signal cable 3, the differential wiring 31, the shielding member 32, the power line 4, the power feed line 41, the ground line 42, and the control line) is arbitrary. [Example]

[0186] The present invention will be described in more detail below with reference to examples and comparative examples. It should be noted that the present invention is in no way limited to these examples and comparative examples. The specific numerical values ​​of the blending ratios (content ratios), physical property values, parameters, etc. used in the following description can be replaced with the corresponding upper limit values ​​(numeric values ​​defined as "equal to or less than" or "less than") or lower limit values ​​(numeric values ​​defined as "equal to or greater than" or "exceeding") of the blending ratios (content ratios), physical property values, parameters, etc. described in the "Description of the Invention" above.

[0187] 1. Relationship between sheath thickness s and optical fiber coating thickness f [Examples 1 to 3 and Comparative Example 1] The relationship between the sheath thickness s and the optical fiber coating thickness f was evaluated by analytical simulation.

[0188] More specifically, the composite cable shown in FIG. 1 was simulated using commercially available structural analysis software (Ansys LS-DYNA (manufactured by Ansys, Inc.)).

[0189] In the simulation, the composite cable included one sheath, 19 first-order tensile strength fibers (the outer fibers of the optical cable), one optical cable, one electrical signal cable, one power line, and four control lines. The optical cable included one optical fiber coating, four plastic optical fibers, and 24 second-order tensile strength fibers (the inner fibers of the optical cable). The electrical signal cable included a pair of differential wiring and one shielding member. The power line included one power feed line and cover, and one ground line. The control line included a cover (not shown).

[0190] In the simulation, the physical properties of each component, except for the thickness f of the optical fiber coating, were set to the same value. An example of the physical properties is shown in Table 1.

[0191] [Table 1]

[0192] The materials and properties not shown in the table were also set to the same values.

[0193] The elastic modulus in the table indicates the tensile storage modulus E' at 26°C. The elastic modulus was calculated by the following method. That is, a master curve was created from dynamic viscoelasticity measurement (DMA) and the elastic modulus was calculated. Specifically, in the dynamic viscoelasticity measurement, a Rheogel E-4000 manufactured by UMB was used to create a master curve under the following conditions, and the tensile storage modulus of each member in the table was calculated. (1) Measurement temperature range: Plastic optical fiber (-100°C to 100°C), cable (-100°C to 150°C) (2) Temperature increase rate: 2°C / min (3) Chuck distance: 20 mm (4) Measurement frequency: 1Hz (5) Strain amplitude: 0.05%

[0194] In the above simulation, the thickness s of the sheath was set to 0.42 mm, and the thickness f of the optical fiber coating material was changed as shown in Table 2.

[0195] [Table 2]

[0196] In the simulation, the above composite cable was fixed to a stainless steel plate, and a stainless steel weight was dropped from a height of 1 m onto the composite cable, and the maximum stress generated in the plastic optical fiber was calculated. The composite cable was fixed using nonwoven fabric tape. The impact speed was assumed to be 4.4 m / s when a 100 g weight was dropped from a height of 1 m.

[0197] The physical properties of the weight and the pressure winding tape are also shown in Table 1 above.

[0198] Figure 2 shows the relationship between the time elapsed since the weight began to fall and the stress value.

[0199] [Consideration] It was confirmed from Figure 2 that excellent impact resistance can be obtained when the thickness f of the optical fiber coating material is 0.65 times or more the thickness s of the sheath.

[0200] Furthermore, it was confirmed from FIG. 2 that excellent impact resistance was obtained when the thickness f of the optical fiber coating material was 0.35 mm or more.

[0201] 2. Fiber content [Reference examples 1~3] A commercially available composite cable was prepared. The sheath thickness s of the composite cable was 0.52 mm, and the tensile storage modulus E' at 27°C was 43 MPa. The optical fiber coating material thickness f was 0.25 mm, and the tensile storage modulus E' at 26°C was 402 MPa.

[0202] The first tensile strength fiber (outer fiber of the optical cable) was removed from a commercially available composite cable, and the amount of the first tensile strength fiber (outer fiber of the optical cable) was changed as shown in Table 3. The amount of the second tensile strength fiber (inner fiber of the optical cable) was 0.99 g / m.

[0203] The composite cable was fixed to a stainless steel plate, and a stainless steel weight was dropped from a height of 1 m onto the composite cable. The optical loss of the plastic optical fiber was measured with a power meter, and the increase in optical loss caused by the weight drop was calculated.

[0204] The above test was carried out at three locations, and each location was repeated three times. The average increase in optical loss was calculated.

[0205] The weight of the weight was increased in increments of 100g from 100g, and the above test was repeated. The weight at which the increase in optical loss exceeded the threshold (0.5dB / 5m) was determined. The results are shown in Table 3.

[0206] [Table 3]

[0207] [Reference examples 4~6] A commercially available composite cable was prepared. The sheath thickness s of the composite cable was 0.52 mm, and the tensile storage modulus E' at 27°C was 43 MPa. The optical fiber coating material thickness f was 0.25 mm, and the tensile storage modulus E' at 26°C was 402 MPa.

[0208] The second tensile strength fiber (fiber inside the optical cable) was removed from a commercially available composite cable, and the amount of the second tensile strength fiber (fiber inside the optical cable) was changed as shown in Table 4. The amount of the first tensile strength fiber (fiber outside the optical cable) was 3.66 g / m.

[0209] The composite cable was fixed to a stainless steel plate, and a stainless steel weight was dropped from a height of 1 m onto the composite cable. The optical loss of the plastic optical fiber was measured with a power meter, and the increase in optical loss caused by the weight drop was calculated.

[0210] The above test was carried out at three locations, and each location was repeated three times. The average increase in optical loss was calculated.

[0211] The weight of the weight was increased in increments of 100g from 100g, and the above test was repeated. The weight at which the increase in optical loss exceeded the threshold (0.5dB / 5m) was determined. The results are shown in Table 4.

[0212] [Table 4]

[0213] [Consideration] It was confirmed from Table 3 that there is no correlation between the amount of the first tensile strength fiber (the outer fiber of the optical cable) and the weight at which the increase in optical loss exceeds the threshold value (0.5 dB / 5 m).

[0214] It was confirmed that there is a correlation between the amount of second tensile strength fiber (fiber in optical cable) and the weight at which the optical loss increase exceeds the threshold (0.5 dB / 5 m). Specifically, it was confirmed from Table 4 that excellent impact resistance can be obtained if the amount of second tensile strength fiber (fiber in optical cable) exceeds 0.1 g / m (for example, 0.2 g / m or more, preferably 0.5 g / m or more).

[0215] In other words, Tables 3 and 4 confirm that the smaller the amount of first tensile strength fiber (external fiber of the optical cable), the better the cost performance, and the larger the amount of second tensile strength fiber (internal fiber of the optical cable), the better the impact resistance.

[0216] In other words, it was confirmed that the greater the proportion of the total cross-sectional area of ​​the second tensile strength fiber (fiber inside the optical cable) to the cross-sectional area of ​​the composite cable is compared to the proportion of the total cross-sectional area of ​​the first tensile strength fiber (fiber outside the optical cable), the better the cost and impact resistance that can be achieved. [Explanation of symbols]

[0217] 1 composite cable 2 Optical Cable 3 Electrical signal cables 4 Power line 5 Sheath 6. First tensile strength fiber 21 Plastic Optical Fiber 22 Optical fiber coating material 23 Second tensile strength fiber 31 Differential wiring 31A 1st wiring 31B 2nd wiring 32 Shielding material 41 Power line 42 Ground Line 310 core wire 311 Covering material

Claims

1. Sheath and a plastic optical fiber disposed inside the sheath; an optical fiber coating material disposed between the sheath and the plastic optical fiber and coating the plastic optical fiber; a power line disposed between the sheath and the optical fiber coating material; Equipped with A composite cable, wherein the thickness s of the sheath and the thickness f of the optical fiber coating material satisfy the following formula (1): f≧0.65s (1)

2. 2. The composite cable according to claim 1, wherein a thickness s of the sheath and a thickness f of the optical fiber coating material satisfy the following formula (2): f≧s (2)

3. further comprising a first tensile strength fiber disposed between the sheath and the optical fiber coating; In a cross section along a direction perpendicular to the longitudinal direction of the composite cable, 2. The composite cable according to claim 1, wherein a ratio of a total cross-sectional area of ​​said first tensile strength fibers to a cross-sectional area of ​​said composite cable is 5% or less.

4. Further, a second tensile strength fiber is disposed between the optical fiber coating material and the plastic optical fiber, In a cross section along a direction perpendicular to the longitudinal direction of the composite cable, The ratio of the total cross-sectional area of ​​the second tensile strength fibers to the cross-sectional area of ​​the composite cable is The composite cable according to claim 3 , wherein the ratio of the cross-sectional area of ​​the first tensile strength fibers to the cross-sectional area of ​​the composite cable is greater than the ratio of the total cross-sectional area of ​​the first tensile strength fibers to the cross-sectional area of ​​the composite cable.

5. In a cross section along a direction perpendicular to the longitudinal direction of the composite cable, 5. The composite cable according to claim 4, wherein a ratio of a cross-sectional area of ​​the optical fiber coating material to a cross-sectional area of ​​the composite cable is 5% or more and 20% or less.

6. 2. The composite cable according to claim 1, wherein the sheath has a tensile storage modulus E'(s) at 26° C. of 100 MPa or less.

7. 7. The composite cable according to claim 6, wherein the sheath has a tensile storage modulus E'(s) at 26° C. of 20 MPa or more and 85 MPa or less.

8. 7. The composite cable according to claim 6, wherein the optical fiber coating material has a tensile storage modulus E'(f) at 26° C. of 200 MPa or more.

9. the tensile storage modulus E'(s) of the sheath at 26°C is smaller than the tensile storage modulus E'(f) of the optical fiber coating material at 26°C; 7. The composite cable according to claim 6, wherein the difference between the tensile storage modulus E'(s) of the sheath at 26°C and the tensile storage modulus E'(f) of the optical fiber coating material at 26°C is 300 MPa or more.

10. The composite cable according to claim 1 , wherein a plurality of said plastic optical fibers are disposed inside one of said optical fiber coating materials.

11. the sheath comprises polyurethane; 10. The composite cable of claim 1, wherein the optical fiber coating comprises polyethylene and magnesium hydroxide.

12. Further, a second tensile strength fiber is disposed between the optical fiber coating material and the plastic optical fiber, 2. The composite cable according to claim 1, wherein the amount of the second tensile strength fibers is 0.20 g / m or more.

13. It is a composite cable, Sheath and a plastic optical fiber disposed inside the sheath; an optical fiber coating material disposed between the sheath and the plastic optical fiber and coating the plastic optical fiber; a power line disposed between the sheath and the optical fiber coating; a first tensile strength fiber disposed between the sheath and the optical fiber coating; a second tensile strength fiber disposed between the optical fiber coating material and the plastic optical fiber; In a cross section along a direction perpendicular to the longitudinal direction of the composite cable, The ratio of the total cross-sectional area of ​​the second tensile strength fibers to the cross-sectional area of ​​the composite cable is A composite cable in which the proportion of the total cross-sectional area of ​​the first tensile strength fibers to the cross-sectional area of ​​the composite cable is greater than the proportion of the total cross-sectional area of ​​the first tensile strength fibers.

14. 14. The composite cable of claim 13, wherein the amount of the second tensile strength fibers is 0.20 g / m or more.

15. Sheath and a plastic optical fiber disposed inside the sheath; an optical fiber coating material disposed between the sheath and the plastic optical fiber and coating the plastic optical fiber; a power line disposed between the sheath and the optical fiber coating material; Equipped with A composite cable, wherein the thickness f of the optical fiber coating material is 0.35 mm or more.

16. Further, a second tensile strength fiber is disposed between the optical fiber coating material and the plastic optical fiber, 16. The composite cable of claim 15, wherein the amount of the second tensile strength fibers is 0.20 g / m or more.

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