JPH07128552A - Spacer for cable - Google Patents

Abstract

PURPOSE:To provide the spacer for a cable which has a high linear elastic modulus, excellent creep resistance and heat resistance, low water absorptivity and slipperiness and excellent durability and handleability by using a high polymer material having specific physical properties as the spacer for the cable formed with spiral or corrugated line grooves housing wires for the cable. CONSTITUTION:The wires B for the cable are housed and protected in the spacer A. The high polymer material having the linear elastic modulus of >=45GPa, a creep strain of <=2% at 50 deg.C and an average creep speed of <=2,0X10<-8>sec<-1> is used as the constituting blank of such spacer A and the spacer is so formed as to have a cross sectional area of <=4mm<2>. One or plural lines of the spiral line grooves 1 are formed on the long-sized material consisting of such material and the wires B for the cable are housed and protected in these spiral line grooves 1. The line grooves 1 may be spiral or corrugated grooves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spacer used for protecting a cable such as an optical fiber, and more particularly, it prevents the cable from being damaged by various external forces received when it is put into practical use as a cable wiring, and is severe. The present invention relates to a spacer for protecting a cable that can stably maintain transmission characteristics even under environmental conditions of various electric and magnetic fields. Hereinafter, in the present specification, the description will proceed mainly on the spacer used for the optical fiber cable.

[0002]

2. Description of the Related Art As is well known, an optical fiber suffers from deterioration of transmission characteristics under the influence of external stress such as tensile stress, compressive stress, bending force, and contraction / expansion force due to temperature change. Therefore, in order to improve these problems,
Attempts have been made to reinforce the optical fiber with a strength member, and various reinforcing materials and methods have been proposed. For example, Japanese Patent Application Laid-Open No. 58-216205 discloses an optical fiber cable in which a high-strength fiber group is arranged so as to surround an optical fiber, and an outer peripheral portion is impregnated and integrated with a filler to form a reinforcing layer. See also 63-
Japanese Patent No. 188614 describes a spacer having a structure in which a longitudinal strip of a polymer material having a tensile strength member embedded therein is provided with a spiral slot in the longitudinal direction, and an optical fiber is housed in the slot. Furthermore, in Japanese Utility Model Publication No. 1-103811,
A spacer for cables of the type in which a spiral groove is bored in the longitudinal direction of a long polymer material having a reinforcing function by itself without holding a tension member inside, and an optical fiber is accommodated in the groove is proposed. There is.

However, among the above-mentioned conventional techniques, in the type in which the outer peripheral surface of the optical fiber is covered with a fiber group or impregnated resin for reinforcement, the tensile stress at the time of laying is irrespective of how the tensile strength fiber or the like is selected. It is not possible to completely prevent the residual stress after laying or laying on the optical fiber core wire, and the transmission characteristics of the optical fiber cable are adversely affected to some extent. On the other hand, the method using the spacer having the spiral groove is less susceptible to the deformation due to the tensile stress and the compressive stress as compared with the above-mentioned coating-reinforced optical fiber cable, but, for example, in Japanese Utility Model Publication No. 63-188614. Non-metallic spacers made of high tensile modulus elastic materials such as those disclosed, for example, ultra-high molecular weight polyethylene, generally have poor creep resistance, resulting in poor transmission characteristics due to residual stress after laying optical fiber cables. To do. Therefore, in order to solve these problems, it is possible to make improvements such as making the pitch of the spiral groove of the spacer forming body finer or increasing the diameter of the spacer, but even if any measure is taken, it is accompanied by it. Since the amount of the optical fiber core wire used per unit length of the spacer forming body increases, the expected effect cannot be obtained. Therefore, it is necessary to take measures such as suppressing the stress at the time of laying the optical fiber cable as much as possible or removing the stress after the laying, and the cable laying workability and handleability are impaired, which is unrealistic.

On the other hand, in order to ensure the accommodation of the optical fiber accommodated in the groove formed in the spacer forming body, it is conceivable to melt and join the optical fiber wire in the groove using a thermoplastic resin. However, since the spacer-forming body made of ultra-high molecular weight polyethylene or the like as disclosed in the above-mentioned publication has a low melting point and poor adhesiveness, the selection range of the type of the thermoplastic resin for fusion bonding is very narrow, and Since the spacer-formed body is very slippery, there is a problem in handleability during storage / storage and laying work.

On the other hand, when the aramid polymer is used as the spacer material, the problems of creep resistance and slippage of the cable surface are solved, but the mechanical properties of the material are easily affected by moisture, so that it is stable over a long period of time. It is not suitable as a spacer for cables that requires transmission.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the problems of the prior art as described above, and its purpose is to have a high tensile elastic modulus and excellent creep resistance and heat resistance. Moreover, the present invention intends to provide a cable spacer having low water absorption and slipperiness and excellent durability and handleability.

[0007]

The structure of the cable spacer according to the present invention, which has been able to solve the above-mentioned problems, is as follows.
A cable spacer having a spiral or wavy groove for accommodating a cable wire along the longitudinal direction of a long material, having a tensile modulus of 45 GPa or more and a creep strain of 2% or less at 50 ° C. Average creep speed is 2.
0 × 10 ^-8 sec ^- consists of ^a less polymeric material and has a gist at the cross-sectional area is 4 mm ² or more. Another configuration according to the present invention is a cable spacer in which a spiral or corrugated groove for accommodating a cable wire is formed along a longitudinal direction of a sheath material in a core-sheath type long material, The core material is made of a polymer material having a tensile elastic modulus of 45 GPa or more, a creep strain at 50 ° C. of 2% or less, and an average creep rate of 2.0 × 10 ⁻⁸ sec ⁻¹ or less, and a sheath material. Has a melting point or decomposition temperature of 30
The gist resides in that it is composed of a polymer material at 0 ° C. or lower and has a cross-sectional area of 4 mm ² or more as a whole.

[0008]

The cable spacer according to the present invention has a function of safely storing and protecting the optical fiber core wire, the optical fiber bare wire, the optical fiber tape and the like in the cable without causing stress on the cable wire material. The basic structure is as illustrated in FIGS.

That is, FIG. 1 is a partial sketch and FIG. 2 is a cross section, both showing a state in which a cable wire B is housed and protected in a spacer A. And this spacer A
As described later, one or a plurality of (four in the illustrated example) spiral grooves 1 are formed in a long material made of a polymer material whose physical properties are specified, and a cable is provided in the spiral grooves 1. The wire material B is stored and protected. The groove may have a corrugated shape as well as a spiral shape.

In the present invention, as a constituent material of the spacer A, the tensile elastic modulus is 45 GPa or more, the creep strain at 50 ° C. is 2% or less, and the average creep rate is 2.0 × 1.
A polymer material of 0 ^-8 sec ^-1 or less is used. Hereinafter, the reasons for defining these physical properties will be described in detail.

First, a polymeric material having a higher tensile elastic modulus is preferable because the tensile strength of the spacer is also increased. However, in general, in order to increase the tensile strength of a polymer material, it is necessary to increase the molecular weight of the polymer used as the material, and a special technique is also required for molding the polymer. The productivity including the processing process will decrease. Therefore,
Considering the practicability, it is important to set the upper limit of the tensile modulus in consideration of the balance between the allowable productivity and the required tensile strength. When a polymer material with a tensile elastic modulus of less than 45 GPa is used, it is possible to increase the tensile strength by increasing the cross-sectional area of the spacer. However, the increase in the weight of the spacer accompanying this causes an increase in creep due to its own weight. It is disadvantageous in terms of sex. Therefore, in the present invention, as a requirement for ensuring sufficient tensile strength without causing such a problem, it is essential to use a polymer material having a tensile elastic modulus of 45 GPa or more.

Further, the creep strain of the polymer material is 2.
If it exceeds 0%, the cable wire is likely to be deformed due to the influence of the tension received when the cable is laid. As described above, the spacer of the present invention has a spiral or corrugated groove formed on the outer periphery thereof, and since the cable wire is housed in the groove, the length of the spacer itself is for the cable. Shorter than wire. Therefore, the amount of deformation of the spacer itself is absorbed by the difference length between the two, but when the spacer is deformed beyond the difference length, the cable wire material is affected by the deformation and the transmission property is reduced. The difference between the length of the spacer itself and the length of the cable wire can be adjusted by the pitch of the spiral groove or the wavy groove or the outer diameter of the spacer. For example, if the pitch of the groove is reduced, the difference length can be increased. . Depending on the outer diameter of the spacer, a spacer made of a polymer material with creep strain exceeding 2.0%,
The pitch of the spiral and the wave for absorbing the deformation must be made extremely small, which becomes unrealistic. Therefore, in the present invention, considering the temperature conditions of the cable laying environment,
The upper limit of creep strain in was set to 2.0%.

Further, in the present invention, the average creep rate of the spacer is also important, and it must be 2.0 × 10 ^-8 sec ^-1 or less. By the way, the average creep speed is 2.0 ×
In the case of a polymer material exceeding 10 ^-8 sec ^-1 , the spacer may be deformed due to residual stress during installation and its own weight, which may cause deterioration of transmission property, which is a problem of so-called durability. .

The constituent material of the cable spacer according to the present invention is made of a polymer material having the above-mentioned physical properties, and the kind thereof is not particularly limited. For example, polyester resin, polyamide resin, Examples thereof include polyolefin resins such as polyethylene and polypropylene, and polybenzazole resins which are recently developed polymer materials. These may be used alone or may be a blend of two or more kinds, but the molecular weight and blending ratio are adjusted so that the physical properties of the final molded product (spacer) satisfy the above-mentioned requirements. Adjustment is essential.

When the cable wire is housed in the groove formed in the outer peripheral portion of the spacer made of a polymer material as described above,
A cable unit is obtained. Normally, it is put into practice by applying a winding process to the outer circumference of this unit, but at this time, if the cable wire is coated with a thermoplastic resin and the resin is melted and fixed to the spacer, the spacer and the cable wire are separated. This is preferable because the integration of the two becomes more reliable. When used in such an embodiment, it is preferable to use a heat-resistant polymer material that withstands heat at the time of melting and fixing as a spacer material, and from this viewpoint, one of the preferable polymer materials is polybenzazole-based. Polymers may be mentioned.

Therefore, a method for producing a long product made of a polybenzazole polymer, which is a polymer material suitable for the spacer of the present invention, will be described below. For example, the intrinsic viscosity measured at a temperature of 25 ° C with methanesulfonic acid as a solvent is 25d.
As a method for producing a long product for a spacer from a polybenzazole-based polymer of 1 / g or more, a polybenzazole-based polymer dope polymerized by using polyphosphoric acid as a solvent is discharged from a spinneret, and the dope is placed below the spinneret. After passing through the non-solvent liquid placed in, then shaken off with a traction device while adjusting the speed of the strands with a roller group, and subsequently washing the strands with the non-solvent liquid, and further with an inert gas stream. It can be obtained by drying in. still,
Specific preferred examples of the polybenzazole-based polymer include:
Examples include polyparaphenylene benzbisoxazole and the like.

The cable spacer of the present invention is formed by forming one or more, preferably a plurality of spiral or corrugated groove grooves for accommodating the cable wire material in a long product made of a polymer material satisfying the above-mentioned characteristics. The long body serving as the spacer body is usually manufactured in the form of a strand or a sheet, and a method of adjusting the cross-sectional shape and the outer diameter according to this shape is applied. For example, in the case of manufacturing in a strand form, it may be shaped into a target size and shape in the manufacturing stage. In the case of manufacturing in a sheet form, a laminated body obtained by slitting the sheet and superposing the sheet is predetermined with a drawing die. It can be shaped to the dimensions and shape of.

The outer shell shape of the cross section of the spacer body is not limited to a circular shape, and may be an elliptical shape or a polygonal shape.
And the cross-sectional dimension is at least one cable wire (for example, an optical fiber-core wire usually has a diameter of 0.9 m).
It is necessary to have a size capable of forming a groove for accommodating about m. Then, for example, a U-shaped groove (for example, width w = 1.5 mm, depth = 1.5 mm, radius = 0.75) is formed in the spacer body having a circular cross section.
mm), the outer diameter of the spacer body is 4 mm
It is preferable to set it to a degree or more. At that time, the cross-sectional area of the spacer after forming the groove is 4 mm ² or more. At this time, the cross-sectional area of the spacer after forming the groove is 4 mm.
^If it is less than ² , not only will the storage and protection of the cable wire material be deteriorated, but it will be difficult to obtain the necessary tensile strength in terms of handleability when laying the cable, so the cross-sectional area is 4 mm ^2.
The dimensions should be adjusted so that it is more than a certain degree.

The cross-sectional shape of the groove is not particularly limited as long as at least one cable wire is accommodated loosely, and this groove has a spiral shape along the outer peripheral portion in the longitudinal direction of the spacer. Alternatively, it is formed into a corrugated shape. By loosely accommodating the cable wire in the spiral or corrugated groove, it is possible to prevent external force such as bending from directly acting on the cable wire.

Here, the pitch of the spiral or corrugation should be set in consideration of the creep strain of the spacer, but it is preferably set to 20 mm or more and 500 mm or less. If it is less than 20 mm, the amount of cable wire used to secure a predetermined transmission length is relatively increased, resulting in an increase in cost. If the pitch exceeds 500 mm, the deformation due to the creep strain of the spacer is caused by the cable wire material. The transmission characteristics tend to deteriorate, and deterioration of the transmission characteristics tends to occur.

As a method for forming the groove on the spacer body, for example, a method for forming the groove using a cutting device having a cutting die as shown in FIG. 3 or for a spacer using a drawing die is used. In the process of manufacturing a long product, a die may be modified to have a structure capable of simultaneously forming grooves, and the spacer main body may be shaped while forming the grooves while rotating the die. The method for forming the groove is not limited to these methods, but in order to improve the accuracy of the groove, the elongated groove for spacer is once formed and then the groove is formed by post-processing using a cutting device. Is the way to do it.

By the way, in the above description, an example in which the spacer is basically formed of a single polymer material has been shown. However, as described above, the polymer material used in the present invention has a tensile elastic modulus of 45 GPa or more, Creep strain at 50 ° C is 2% or less, average creep rate is 2.0 × 10 ^-8 sec
^Since it must have physical properties such as ^-1 or less and has particularly poor machinability, it is quite difficult to subsequently form spiral or corrugated grooves by cutting.

However, for example, as shown in FIG. 4 (transverse sectional view), the spacer has a core-sheath structure, and the core portion A ₁ has a tensile elastic modulus of 45 GPa or more and a creep strain of 2% or less at 50 ° C. as described above, and an average. Creep speed is 2.0 × 10 ^-8
While the polymeric material with sec ^-1 following physical properties requirements, sheath A ₂ is when the spacer of the composite structure having a melting point or decomposition temperature of from 300 ° C. or less of soft polymer material, the core A ₁ The excellent physical properties as described above ensure the strength to withstand the external force during cable laying, and the spiral or corrugated groove 1 can be easily formed by cutting the sheath made of a soft polymer material. Thus, a cable spacer that satisfies both the protection characteristics and workability can be obtained.

Therefore, it can be said that the spacer having the composite structure as shown in FIG. 4 is the most practical in consideration of the productivity including the forming workability of the groove. If the melting point or the decomposition temperature of the polymer material forming the sheath A ₂ exceeds 300 ° C., the processability of the groove 1 will not be improved so much, and the advantages of the composite structure will not be fully utilized. Disappear. In the spacer having such a composite structure, for example, the long material constituting the core portion A ₁ is prepared in advance by the method as described above, and the long material is passed through the central portion of the extrusion molding die. It can be manufactured by a method of extruding a soft polymer material forming the sheath A ₂ around it, etc., and the groove 1 is formed in the sheath A ₂ by cutting as described above. A method, or a method of forming a groove at the same time as extruding the coating onto the core portion by devising the shape of the extrusion molding die may be adopted.

The spacer of the present invention thus selected is
It has much better mechanical properties and cable wire protection properties than the conventional spacers, and can eliminate all the problems of the conventional spacers.

In the present specification, the case where the spacer is used as a spacer for an optical fiber cable has been mainly described.
The excellent cable wire protecting function is effectively exerted even when used as a spacer for a cable wire of a sensor cable, a control cable, a welding device cable, or the like.

[0027]

EXAMPLES The constitution and effects of the present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples, and
Modifications can be made within a range that is compatible with the gist of the description below, and all of them are included in the technical scope of the present invention.

The measuring methods of various characteristic values adopted in the following examples are as follows. <Creep resistance> The creep resistance was evaluated by the following two measured values. That is, a load equivalent to 1/3 of the breaking strength is applied to the sample (cable spacer), and the original sample length is L _0.
(Cm), the sample length after 2 hours in an atmosphere of 50 ° C. is L ₁ (cm), and the sample length after 22 hours is L ₂ (cm)
Was measured, and the creep strain ε _t (%) and the average creep rate ε (sec ⁻¹ ) were calculated by the following formulas.

Ε _t = (L ₁ −L ₀ ) × 100 / L ₀ (%) ε = (L ₂ −L ₁ ) / (20 × 3600 × L ₀ ) (se
c ^-1 )

<Tensile Modulus of Spacer-Forming Body> JIS
In accordance with L-1013 (1981), a tensilon manufactured by Orientec Co., Ltd. was used to measure n = 10 at a gripping interval of 20 cm and a pulling speed of 100% / min.
It was calculated from the maximum slope near the origin of the elongation curve. <Bending test> Using the spacer type optical fiber unit 4m as a sample, the optical transmission loss of the optical fiber was evaluated after bending the metal car having a radius of 250 mm 180 degrees and repeating the bending test 10 times with a tension of 10 kg. An optical transmission loss of 0.20 dB / Km or less was judged to be good. <Heat Cycle Test> The spacers containing the optical fiber in the groove were alternately left in the atmosphere of −40 ° C. and + 60 ° C. for 1 hour each 50 times, and the optical transmission loss of the optical fiber was evaluated. Optical transmission loss is 0.2
A value of 0 dB / Km or less was judged to be good.

Examples 1 and 2, Comparative Example 1 A polybenzazole polymer [poly (paraphenylene benzbisoxazole)] dope polymerized with polyphosphoric acid as a solvent was spun from a spinneret having pores with a diameter of 5.0 mm. After discharging, it was passed through a water tank arranged 250 mm below the spinneret, the speed was continuously adjusted by a roller with a peripheral speed of 20 m / min, the discharged material was washed with water, and then filled with water by a traction device. Shake into a container and continuously supply water into the container while the amount of residual phosphorus in the strand is 2
Wash until 000 ppm or less. Next, the strand was allowed to stand in a nitrogen stream and dried until the water content became 2% or less. The obtained strand was used as a long spacer material and was passed through a cutting die as shown in FIG.
The spiral groove of the book was cut and formed. The width of the groove is 1.3 mm,
The depth d was 1.9 mm, the radius r was 0.7 mm, and the U-shape was 100 mm, the spiral pitch was 100 mm, and the cross-sectional area S of the spacer body was 10.5 mm ² .

Next, in the spiral groove of the spacer, one optical fiber core having an outer diameter of 0.9 mm, which is secondarily coated with nylon 6 resin, is housed, and the outer periphery of the optical fiber core wire is pushed to form a spacer type optical fiber unit. Got The strand used in this experiment was 25% with methanesulfonic acid as a solvent.
Intrinsic viscosity measured at a temperature of ° C of 17, 28 and 33d
It was produced from 1 / g of three kinds of polybenzazole-based polymers, and various properties of the obtained spacers are shown in Table 1.

[0033]

[Table 1]

As is clear from Table 1, Examples 1 and 2
And the tensile strength (= tensile elastic modulus × spacer cross-sectional area) of Comparative Example 1 is 86,500 kg, 66,000 kg and 45.6.
It is 00 kg. The tensile elastic moduli of Examples 1 and 2 satisfy the requirements of the present invention, whereas the tensile elastic moduli of Comparative Examples are less than 45 GPa, and the allowable tension which is a measure of handleability when laying an optical fiber cable. (= Tensile strength ×
0.2%) are 173 kg and 133 k in Examples 1 and 2.
It can be seen that the comparative example has a low value of 91 kg, but lacks handleability. The heating cycle test results show that the optical transmission loss is 0.07 dB / Km in all cases, and that the change in optical transmission property in the repeated bending test is at a practical level. Also, it can be said that the creep resistance is at a level where there is practically no problem.

Comparative Examples 2 to 4 In Comparative Example 1, the spacer has a diameter of 5.0 mm.
To 6.1 mm, the tensile strength was adjusted to that of Example 1, and a groove was formed under the same conditions as in Comparative Example 1 to give Comparative Example 2. Further, the cross-sectional area (1
Comparative Example 3 was obtained by cutting and forming grooves in the same manner as in Example 1 except that 0.5 mm ² ) was changed to 3.7 mm ² .
In addition, Comparative Example 4 was prepared by changing only the number of grooves to 1 without substantially changing the spacer cross-sectional area in Comparative Example 3. Table 2 shows various properties of each spacer.

[0036]

[Table 2]

In Comparative Example 2, the spacer diameter was increased to make the allowable tension at the same level as in Example 1 as described above, but the spacer weight per unit length was increased accordingly and the handleability was improved. It is not preferable because it decreases and causes increase in creep strain due to its own weight. Further, as is apparent from Comparative Examples 3 and 4, when the cross-sectional area of the spacer is less than 4 mm ² , the allowable tension is low and the handleability is poor even if a polymer material having a tensile elastic modulus of 45 GPa or more is used. I understand.

Comparative Examples 5 to 6 The contents described in Japanese Patent Application Laid-Open No. 61-268430 were additionally tested as they were to make Comparative Example 5. That is, high density polyethylene having a viscosity average molecular weight of 2 × 10 ⁶ was dissolved in decalin by the method described in the above publication and then cooled, and the obtained gel particles were compressed by a roller press. This compressed sheet was slit, overlapped and supplied to a drawing die, and die drawing was performed at 90 ° C. The drawn drawing die obtained was subjected to multi-stage drawing in a heated air tank at the first stage of 120 ° C. and then at 135 ° C. to make a long product for spacers having a circular cross section, the outer peripheral surface of which was formed in the same manner as in Example 1 above. The groove was cut and formed. Also,
Comparative Example 6 was modified so that the cross-sectional area of the spacer was the same as in Example 1. Table 3 shows various properties of the obtained spacer.

[0039]

[Table 3]

As is clear from Table 3, the conventional spacer of Comparative Example 5 needs to have a large cross-sectional area in order to secure an allowable tension, which is larger than that of the spacer of Example 1 per unit length. The weight is 1.75 times. Further, since this material has a large creep strain of 8.0%, the performance as a spacer is insufficient in terms of handling properties before and after installation and fluctuations in light transmission due to residual tension after installation. On the other hand, Comparative Example 6
In comparison with Example 1, the allowable tension is 67 kg, which is low and the handling property is poor.

Example 3 and Comparative Example 7 The strand of polybenzoxazole described in Example 1 was wound up in a package, and the strand was pulled out from the feeding device at a constant tension and passed through the center of the extrusion molding die. The outer circumference of the scale material was coated with a melted polyethylene terephthalate resin so as to have a uniform thickness.
Subsequently, the coating was cooled to a temperature of 80 ° C. or lower and then wound into a package by a winder while the speed was regulated by a take-up device having a caterpillar. Four spiral grooves were cut and formed by the same method as in Example 1 in the sheath portion of the obtained long product for spacers having a composite (core / sheath) structure. next,
This was processed under the same conditions as in Example 1 to obtain a spacer type optical fiber unit.

Comparative Example 7 was carried out in the same manner as in Example 3 except that the resin coated in Example 3 was changed from polyethylene terephthalate to polyether nitrile [trade name ID300, manufactured by Idemitsu Kosan Co., Ltd.]. did. Table 4 shows various properties of each spacer.

[0043]

[Table 4]

In Example 3, the coating process by melt extrusion was stable, and since the polyethylene terephthalate resin was softer than the polybenzoxazole resin, the cutting process was easy. Further, as is clear from Table 4, the cable characteristics are at the same level as in Example 1. On the other hand, in Comparative Example 7 in which polyether nitrile was used as the resin forming the sheath, the cable characteristics were at the same level as in Example 1, but the melt extrusion temperature (370) higher than that of the polyethylene terephthalate resin was used in the melt extrusion. Since the coating process must be performed at (° C), the thermal stability and operability of the melt during processing are poor, and the processability when forming grooves in the coating is also poor, which is an advantage of a composite structure. Could not be found.

[0045]

As described above, since the cable spacer of the present invention has a high tensile strength and an excellent creep resistance which have never been obtained, it can be used, for example, as a spacer for a densified optical fiber cable. The degree of freedom in designing the optical fiber cable is increased, and the allowable tension is improved, so that the handleability at the time of installation is also improved. Therefore,
By using this spacer, it becomes possible to lay an optical fiber with little loss such as optical transmission even if the conditions before and after laying are severe, which is a great contribution to the industry.

[Brief description of drawings]

FIG. 1 is a partial sketch drawing illustrating a cable spacer according to the present invention.

FIG. 2 is a cross-sectional view illustrating a cable spacer according to the present invention.

FIG. 3 is a perspective view illustrating a cutting die for forming a groove on a spacer body.

FIG. 4 is a cross-sectional view of a spacer showing another embodiment according to the present invention.

[Explanation of symbols]

A Spacer B Cable material for cable A ₁ core material A ₂ sheath material 1 groove

Claims (2)

[Claims] 1. A cable spacer in which a spiral or corrugated groove for accommodating a cable wire is formed along a longitudinal direction of a long material, the tensile elastic modulus of which is 45 GPa.
As described above, a cable spacer characterized by having a creep strain at 50 ° C. of 2% or less and an average creep rate of 2.0 × 10 ⁻⁸ sec ⁻¹ or less and having a cross-sectional area of 4 mm ² or more. . 2. A cable spacer in which a spiral or corrugated groove for accommodating a cable wire is formed along the longitudinal direction of the sheath material in a core-sheath type long material, and the core material is 45 GPa. Has the above tensile modulus and 50 ° C
The creep strain is 2% or less and the average creep rate is 2.0 × 10 ⁻⁸ sec ⁻¹ or less, and the sheath material is a polymer material having a melting point or a decomposition temperature of 300 ° C. or less, A cable spacer having a cross-sectional area of 4 mm ² or more as a whole.