KR200310315Y1 - Optical fiber unit for air blown installation and apparatus for manufacturing the same - Google Patents

Abstract

The optical fiber unit for pneumatic installation in which the negative strip is formed on the outer circumferential surface by mechanical cutting includes an optical fiber and a protective layer surrounding the optical fiber, and one or more negative strips are formed on the outer circumferential surface of the protective layer along the longitudinal direction of the protective layer. The intaglio strip is formed in a spiral or wavy pattern on the outer circumferential surface of the protective layer, and the cross section of the intaglio strip is blunt triangular, semicircular, arc or rectangular. The optical fiber is in the form of a single core, a two core or a ribbon, and the protective layer is composed of a buffer layer or a buffer layer / shell layer or a buffer layer / intermediate layer / shell layer.

Description

Optical fiber unit for pneumatic laying and its manufacturing apparatus {OPTICAL FIBER UNIT FOR AIR BLOWN INSTALLATION AND APPARATUS FOR MANUFACTURING THE SAME}

The present invention relates to an optical fiber unit for pneumatic laying, and more particularly, to an optical fiber unit for pneumatic laying and a manufacturing apparatus thereof having a negative band formed on the outer circumferential surface by using mechanical cutting.

Fiber has long been used as a long-distance high speed transmission medium due to its low transmission loss and large bandwidth. However, since the optical fiber itself is very vulnerable to external impact or bending, in order to install the optical fiber, the optical fiber has been manufactured to prevent breakage through the coating of the polymer material at the same time.

Conventionally, a method of laying an optical fiber has been used to bundle and twist the optical fiber in several strands, then cable the installation. Fiber optic cables include multiples of 6 or 12 multiples of fiber and generally install much more fiber than necessary at the time of installation, taking into account future demand. However, due to the diversification of communication systems that can cope with new communication environments and capacities and the variety of optical fibers, the existing method of laying a large amount of specific optical fibers without considering the future environment is desirable. Can't. In addition, it is difficult to determine in the present time which optical fiber or optical cable will be applied in terms of the user terminal, that is, the access network part or the premise wiring. Therefore, it is economically undesirable to lay a large amount of particular fiber optic cable at a high cost.

Recently, a method of laying an optical unit using a pneumatic pressure has been widely adopted for the purpose of laying using a narrow space. An attempt to deploy an optical fiber unit using pneumatic pressure was first presented in US Pat. No. 4,961,896, filed by British Telecom, UK, around 1980. Also known as Air Blown Fiber (ABF), this technology uses a diameter of five to five microtubes or ducts with a special composition for lubrication so that the user can additionally embed the optical fiber whenever needed. The tube of about 8mm polymer is buried in the installation area in advance, and the optical fiber unit composed of 1 to 12 cores is blown by air pressure as much as necessary.

This ABF is not only easy to install but also easy to remove, small in size and flexible, which not only reduces initial installation cost, but also reduces the burden on additional installation and facilitates up grade in the future. In particular, ABF is suitable for indoors such as FTTH (Fiber To The Home), home network, and the like.

Since ABF installs only the tubes required for laying, it is hardly restricted even if the installation space such as pipelines is not free. The general process involved in laying ABF is as follows:

First, prepare a dedicated tube for pneumatic laying and install in advance in the required section, and install the necessary optical fiber unit (ABF) by blowing into the tube using a pneumatic laying head (Blowing head). The ABF has the structure and material that can maximize the fluid towing force on the outer surface of the optical fiber unit because it is the biggest difference from the existing method to install using the fluid drag force of the fluid. In addition, since the installation characteristics such as the installation distance and the minimum installation radius vary depending on the structure and material of the ABF outer surface, the shape and material design of the outer surface are very important.

To date, there are various types of ABF structures for increasing the flow traction of the fluid, and representative patent technologies include US5,042,907, US5,533,164, US5,555,335, US4,440,053, US6,341,188. They mainly disclose the improvement of the ABF outer surface.

First, US Pat. No. 5,042,907 proposes a method of manufacturing an optical fiber unit using glass beads 5 on an outer surface in order to receive more air pressure as shown in FIG. In order to form the glass beads 5 on the outer surface of the optical fiber, the glass beads 5 are pre-stirred to the coating resin of the optical fiber 1 and then uniformly applied. However, when using this method, the glass beads 5 contained in the resin 4 on the outer surface of the optical fiber should have a relatively high Young's modulus in order to impart a larger and larger driving force than the thickness of the coating layer. As a result, the optical fiber unit has a relatively poor bend characteristic, and a crack occurs between the glass beads 5 and the resin 4, thereby causing a problem of propagating the cracks into the optical fiber.

In order to solve this problem, a technique of inserting an intermediate layer (3) between the inner buffer layer 2 and the resin 4 on the outer surface has been proposed. In this case, however, the coating has to be repeated three or more times, resulting in a complicated process and an increase in cost.

In addition, as another embodiment, the technique proposed in US Pat. No. 5,555,335 is shown in FIG. 2. Referring to FIG. 2, the patent does not pre-agitate the glass beads 5 to the resin, but the resin is coated on the optical fiber 1, and then the glass beads are blown before hardening, and electrostatically attached to the outer surface 6 of the optical fiber. Is proposing. However, this method has a problem that it is difficult to apply to the actual process because the adhesion strength between the glass beads and the outer surface of the optical fiber is not evenly distributed. In particular, if some glass beads are dropped, the glass beads may damage the optical fiber unit during the laying operation or be inhaled by the operator, causing a fatal problem for the human body.

As another example, US Pat. No. 5,441,813 proposes a technique of forming a concave dimple on the surface of an optical fiber by using an expandable polymer material so that the optical fiber unit receives a lot of air pressure. However, when the foamable polymer material is used, the friction coefficient of the outer surface of the ABF is increased to shorten the distance to be laid at once, and the low temperature characteristic is degraded by the relatively large polymer layer, and the strength of the optical fiber unit is lowered. This occurred.

In addition, in the case of ribbon optical fiber, a method of wrapping and wrapping a fiber of a special material has been proposed, but since the ribbon optical fiber has a direction against bending, it is found to be vulnerable such as bending only in one direction when laying. It became.

The present invention was devised to solve the above problems, and the coating layer of the optical fiber unit maintains a circular cross section so that directionality does not occur when laying, and the surface of the coating layer forms various intaglio bands to receive a lot of fluid traction. At the same time, the object of the present invention is to provide a fiber-optic unit for pneumatic installation, which can be manufactured safely without using fine particles such as glass and ceramics.

Another object of the present invention is to provide an apparatus for manufacturing a pneumatic laying optical fiber unit for manufacturing a pneumatic laying optical fiber net that can simplify the manufacturing process by manufacturing the above-described pneumatic laying optical fiber unit by a mechanical processing process. .

The following drawings attached to this specification are illustrative of the preferred embodiments of the present invention, and together with the detailed description of the present invention to serve to further understand the technical spirit of the present invention, the present invention is a matter described in such drawings It should not be construed as limited to.

1 is a cross-sectional view showing an optical fiber unit according to the prior art.

2 is a cross-sectional view showing another optical fiber unit according to the prior art.

Figure 3 is a perspective view showing a fiber unit for pneumatic installation according to an embodiment of the present invention.

Figure 4 is a perspective view showing a fiber unit for pneumatic installation according to another embodiment of the present invention.

5A to 5F are cross-sectional views illustrating a negative band formed on a surface of an optical fiber unit having various structures.

6A to 6C are cross-sectional views illustrating a negative band formed on a surface of an optical fiber unit having various structures in which an optical fiber ribbon is used.

7 schematically shows a facility for manufacturing an optical fiber unit according to the present invention;

<Explanation of symbols for the main parts of the drawings>

10 .. Optical fiber 12 .. Primary coating layer 14 .. Coloring coating layer

20. Protective layer 22. Buffer layer 24. Outer layer

26. Middle layer 30, 40. Engraved strip 60. Payoff

70. Coating die 80. UV curing machine 90. Machining device

92. Motor 94. Control unit 100. Take-up device

In order to achieve the above object, the optical fiber unit for pneumatic installation according to the present invention is an optical fiber; And a protective layer surrounding the optical fiber, and one or more intaglio bands are formed on an outer circumferential surface of the protective layer along the longitudinal direction of the protective layer.

In this case, the intaglio may be formed in a spiral or wavy pattern on the outer circumferential surface of the protective layer.

In addition, the cross section of the intaglio may be blunt triangle, semi-circular, arc-shaped or square.

In this case, the optical fiber is a plurality, the plurality of optical fibers may be present in the form of a ribbon in the protective layer, a tensile reinforcing member for strengthening the tensile strength with the ribbon-shaped optical fiber may be provided in a ribbon form. At this time, the tensile reinforcing member is added to or replaced with a plurality of optical fibers. In addition, the tensile reinforcing member is preferably Kevlar fiber, Aramid fiber or wire.

In addition, in the above-described configuration, the protective layer may be composed of only a buffer layer, wherein the buffer layer includes a plurality of hollow spheres in the form of fine particles for weight reduction, and the hollow spheres are formed on the outer surface of the protective layer. It is preferable that the buffer layer is formed without affecting, and the buffer layer has a strain secant modulus of 400 MPa to 1000 MPa at 2.5% strain.

As another example, the protective layer may be composed of a buffer layer and a shell layer, wherein the shell layer preferably has a secant modulus of 400 MPa to 1000 MPa at 2.5% strain, and more preferably 500 MPa to 800 MPa secant modulus at 2.5% strain. Has An intermediate layer may also be added between the buffer layer and the skin layer described above.

According to yet another aspect of the present invention, there is provided an apparatus comprising: means for supplying an optical fiber unit having at least one optical fiber and at least one protective layer surrounding the optical fiber; Machining means for forming one or more intaglio bands along the longitudinal direction of the protective layer on the outer peripheral surface of the protective layer of the supplied optical fiber unit; And a take-up means for winding up the optical fiber unit processed by the machining means.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in this specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventors will properly describe the concept of terms in order to best explain their own design. Based on the principle that it can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical ideas of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

3 is a perspective view showing an optical fiber unit for pneumatic installation according to an embodiment of the present invention. Referring to FIG. 3, the optical fiber unit of the present invention includes an optical fiber 10 and a protective layer 20.

The optical fiber 10 is formed of a core and a clad, and one or more optical fibers are provided in the form of a single core or a ribbon. This optical fiber 10 also has a core and a clad as a quartz or plastic optical fiber. Primary and secondary coating layers for protecting the optical fiber may be formed around the optical fiber 10 described above. This coating serves to protect the inner layer from dirt and moisture and is made of silicon or similar buffer material. In addition, a coloring coating layer for identifying the type of optical fiber may be used as the secondary coating layer. In addition, when easy strippability is required depending on the type of polymer resin applied to the coloring coating layer, an optical cable jelly or silicone oil may be applied to the outer circumferential surface of the coloring coating layer.

The protective layer 20 is formed around the optical fiber 10 described above, and around the coating layer when the primary and secondary coating layers are formed. The protective layer 20 may be formed of only one type, or may be configured by stacking various types of protective layers. As an example, the protective layer 20 is formed in a double structure of the buffer layer 22 and the outer skin layer 24. Here, the buffer layer 22 is a protective layer directly surrounding the optical fiber 10, and the outer skin layer 24 is a protective layer in which the intaglio band 30 to be described later is formed. The protective layer 20 of the present invention, however, is not limited to the above examples, and may include various forms of modification. For example, the protective layer 20 may be composed of only the buffer layer 22, and may further include an intermediate layer between the buffer layer 22 and the outer skin layer 24 described above. Various kinds of such protective layers 20 will be described in detail later. In addition, the protective layer 20 performs various roles such as protecting the optical fiber and securing the rigidity of the optical fiber according to the type of application.

In such an optical fiber unit, an intaglio band 30 is formed to assist the air pressure installation. The intaglio strip 30 is formed on the outer circumferential surface of the protective layer 20 by mechanical processing. In particular, when the protective layer 20 is composed of a plurality of layers, the negative strip 30 is formed on the outer peripheral surface of the outermost protective layer.

The intaglio 30 is formed along the longitudinal direction of the protective layer 20 on the outer circumferential surface of the protective layer 20. In addition, although only one intaglio 30 is formed on the outer circumferential surface of the protective layer 20, it is also possible to simultaneously form a plurality of intaglio 30. In addition, the intaglio strip 30 may be formed in a straight shape on the outer circumferential surface of the protective layer 20, it is more preferable to have a curved shape in order to receive more pressure during air pressure installation. In FIG. 3, the intaglio strip 30 is illustrated as being spirally formed on the outer circumferential surface of the protective layer 20 as an example.

In addition, the intaglio 30 is formed by processing a continuous groove on the outer peripheral surface of the protective layer 20 through mechanical processing. At this time, the cross-sectional shape of the intaglio strip 30 is determined by the shape of the cutting tool used in the machining, the end of the various shapes such as triangles, semicircles, arcs, squares, trapezoids with blunt ends are applied to the intaglio strip 30. Can be.

As such, the intaglio band 30 formed on the outer circumferential surface of the protective layer 20 serves to reduce the contact area with the inner surface of the tube and increase the contact surface with air when the optical fiber unit is installed in a narrow space such as a tube. That is, the contact area between the outer circumferential surface of the protective layer 20 and the inner circumferential surface of the tube is reduced by the intaglio 30 so that the frictional force is reduced, and the area exposed to the air flow during installation is increased due to the compressed air. Make the installation more effective.

The engraved strip 30 formed as described above increases the resistance to the air flow flowing around the protective layer 20 in the air pressure installation process of the optical fiber unit, thereby making it easier to install the optical fiber unit. In particular, when the intaglio strip 30 is formed in a spiral as in this embodiment, the resistance to air pressure becomes larger than when it is straight.

Therefore, in the present invention, it is not necessary to attach particles such as polymer hollow beads or glass beads to the outer circumferential surface of the protective layer 20, and a process of stirring or attaching the beads to the resin is necessary. Do not

4 illustrates an optical fiber unit according to another embodiment of the present invention. The optical fiber unit of this embodiment is almost the same as that shown in FIG. 3, except that the intaglio band 40 formed on the surface of the protective layer 20 has a different form from the above-described embodiment.

In the present embodiment, the intaglio band 40 is formed in a wavy pattern on the outer circumferential surface of the protective layer 20. The intaglio band 40 may be formed on the outer circumferential surface of the protective layer 20. When the intaglio strip 40 is formed as described above, the air flow flowing to the periphery of the intaglio strip 40 is alternately resisted to both sides according to the shape of the intaglio strip 40. Therefore, while the intaglio band 30 of the previous embodiment receives the air resistance only in one direction, the optical fiber unit can be twisted in one direction during the pneumatic laying, whereas the intaglio band 40 of this embodiment has alternating resistance in both directions. There is an advantage that the optical fiber unit can be installed in a twisted state.

The intaglio strips 30 and 40 of various shapes shown in FIGS. 3 and 4 are determined by the operating method of the machining apparatus used. That is, when the machine part rotates only in one direction during the formation of the intaglio band, the spiral intaglio 30 shown in FIG. 3 is formed, and when the machine part rotates in both directions, the wavy intaglio shown in FIG. A band 40 is formed. In addition, in addition to the above-described shape, the intaglio may be implemented in various shapes, the operation method of the machining apparatus is of course determined according to the shape.

5A to 5F show an optical fiber unit in which a single-core or two-core optical fiber is surrounded by various kinds of protective layers.

First, the optical fiber unit shown in FIG. 5A includes an optical fiber 10 therein, and has only a buffer layer 22 as a protective layer around the optical fiber 10. In addition, the intaglio strip 30 described above is formed on the outer circumferential surface of the buffer layer 22. Of course, the intaglio strip 30 formed on the outer circumferential surface of the buffer layer 22 may have various shapes such as a spiral or a wavy pattern, and the cross-sectional shape may also be implemented in various forms.

The optical fiber unit shown in FIG. 5A is the most basic configuration of the optical fiber unit, in which the buffer layer 22 directly surrounds the optical fiber 10 and serves as a protective layer. Therefore, in the present embodiment, the buffer layer 22 is preferably made of a harder material than the buffer layer generally used for the rigidity of the optical fiber unit and the smooth machining of the intaglio 30. Preferably, the buffer layer 22 used in the present embodiment has a modulus of secant modulus of 2.5 MPa or more and a modulus of elasticity of 20 MPa or more, more preferably 100 MPa or more.

The optical fiber unit shown in FIG. 5B has a form similar to that shown in FIG. 5A, but an outer skin layer 24 is further formed on the outer circumferential surface of the buffer layer 22. Thus, the negative strip 30 is formed on the surface of the outer skin layer 24 located at the outermost side of the optical fiber unit.

In the case of this embodiment, since the outer skin layer 24 is formed outside the buffer layer 22, the thing of the kind generally used is suitable. On the other hand, the material of the outer skin layer 24 located outside the buffer layer 22 should be determined in consideration of the rigidity of the optical fiber unit and the smooth machining of the negative strip 30. If the modulus of the outer skin layer 24 is too low, it is difficult to secure straightness when laying the optical fiber unit by air pressure, and if the modulus is too high, cracking due to bending may occur. Therefore, the modulus of the outer skin layer 24 is suitable for 400 ~ 1000MPa at 2.5% strain, more preferably 500 ~ 800MPa at 2.5% strain.

Next, the optical fiber unit illustrated in FIG. 5C has a form in which an intermediate layer 26 is added to the optical fiber unit illustrated in FIG. 5B. The intermediate layer 26 is located between the buffer layer 22 and the skin layer 24 and is not directly affected by the intaglio 30. The intermediate layer 26 serves to protect the crack from propagating therein when a crack such as a crack occurs in the outer layer 24. In the present embodiment, the modulus of the outer skin layer 24 is preferably 400 to 1000 MPa at 2.5% strain, more preferably 500 to 800 MPa. In addition, in the present embodiment, the intaglio band 30 is formed on the surface of the outer skin layer 24 located at the outermost side of the optical fiber unit.

The optical fiber unit shown in FIG. 5D is similar to that shown in FIG. 5B, but the primary coating layer 12 and the secondary coating layer 14 are further formed between the optical fiber 10 and the buffer layer 22. The primary coating layer 12 serves to protect the optical fiber 10, the coloring coating layer for identifying the optical fiber 10 is used as the secondary coating layer (14). In the present embodiment, the modulus of the outer skin layer 24 is preferably 400 to 1000 MPa at 2.5% strain, more preferably 500 to 800 MPa. In addition, in the present embodiment, the intaglio band 30 is formed on the surface of the outer skin layer 24 located at the outermost side of the optical fiber unit.

The optical fiber unit shown in FIG. 5E is similar to that shown in FIG. 5D, but the intermediate layer 26, which serves to protect the cracks from propagating inside when the crack such as a crack occurs in the outer layer 24, has a coloring coating layer. It is further formed between the 14 and the buffer layer 22. In the present embodiment, the modulus of the outer skin layer 24 is preferably 400 to 1000 MPa at 2.5% strain, more preferably 500 to 800 MPa. In addition, in the present embodiment, the intaglio band 30 is formed on the surface of the outer skin layer 24 located at the outermost side of the optical fiber unit.

In the optical fiber unit illustrated in FIGS. 5A to 5E, only one optical fiber 10 is used. This means a single-core optical fiber unit, and the present invention is not necessarily limited to the single-core optical fiber unit. For example, as shown in FIG. 5F, the two-core optical fiber unit can be sufficiently implemented. In FIG. 5F, as an example, the protective layer of the optical fiber has a shape similar to that shown in FIG. 5E, and two optical fibers 10 exist within the protective layer. Each optical fiber 10 is also surrounded by a primary coating layer 12 and a coloring coating layer 14. Also in this embodiment, the modulus of the outer skin layer 24 is preferably 400 to 1000 MPa at 2.5% strain, more preferably 500 to 800 MPa. In addition, in the present embodiment, the intaglio band 30 is formed on the surface of the outer skin layer 24 located at the outermost side of the optical fiber unit.

5A through 5F, two to four intaglio bands 30 are formed on the outer circumferential surface of the protective layer of the optical fiber unit illustrated in each drawing. Here, it is to be understood that the number of the intaglio bands 30 shown in the drawings is not essential to the present invention, and the number of the intaglio bands 30 may be variously changed as necessary. In addition, in the present embodiment, the intaglio band 30 formed in the protective layer may be formed in various shapes such as a spiral or a wave pattern, and may have various cross-sectional shapes such as a triangle, a semicircle, an arc, a rectangle, etc. by the shape of the machining device. Of course you can have.

In addition, although not shown, the buffer layer 22 used for the protective layer may include a plurality of hollow spheres in the form of particulates therein. This hollow sphere is merely to reduce the weight of the buffer layer 22, and is not related to the increase in the fluid pulling force of the optical fiber unit.

6A to 6C show an optical fiber unit in which the optical fiber 10 applies a ribbon optical fiber surrounded by the ribbon 16.

First, the optical fiber unit illustrated in FIG. 6A is formed such that the buffer layer 22 surrounds the ribbon-shaped optical fiber. The ribbon optical fiber is a form in which a plurality of general optical fibers or primary coated optical fibers 10 are bundled by the ribbon 16. The ribbon 16 is made of polyethylene (PE), polyurethane, polyvinyl chloride (PVC), and binds a plurality of optical fibers 10 to protect from the external environment.

In addition, the intaglio strip 30 described above is formed on the outer circumferential surface of the buffer layer 22. Of course, the intaglio strip 30 formed on the outer circumferential surface of the buffer layer 22 may have various shapes such as a spiral or a wavy pattern, and the cross-sectional shape may also be implemented in various forms.

In the optical fiber unit illustrated in FIG. 6A, the buffer layer 22 directly surrounds the optical fiber 10 and serves as a protective layer. Therefore, in the present embodiment, the buffer layer 22 is preferably made of a harder material than the buffer layer generally used for the rigidity of the optical fiber unit and the smooth machining of the intaglio 30. Preferably, the buffer layer 22 used in the present embodiment has a modulus of secant modulus of 2.5 MPa or more and a modulus of elasticity of 20 MPa or more, more preferably 100 MPa or more.

The optical fiber unit shown in FIG. 6B has a form similar to that shown in FIG. 6A, but a coloring coating layer 14 is further formed on the outer peripheral surface of each optical fiber 10 in the ribbon 16, and the outer peripheral surface of the buffer layer 22. An outer skin layer 24 is further formed. Thus, the negative strip 30 is formed on the surface of the outer skin layer 24 located at the outermost side of the optical fiber unit.

In the case of this embodiment, since the outer skin layer 24 is formed outside the buffer layer 22, the thing of the kind generally used is suitable. On the other hand, the outer skin layer 24 located outside the buffer layer 22 preferably has a modulus of 400 to 1000 MPa at 2.5% strain in consideration of the rigidity of the optical fiber unit and the smooth machining of the negative strip 30. It has a modulus of 500-800 MPa at 2.5% strain.

Next, the optical fiber unit illustrated in FIG. 6C has a form in which an intermediate layer 26 is added to the optical fiber unit illustrated in FIG. 6B. The intermediate layer 26 is located between the buffer layer 22 and the skin layer 24 and is not directly affected by the intaglio 30. Also, in the present embodiment, the negative strip 30 is formed on the surface of the outer skin layer 24 located at the outermost side of the optical fiber unit as in the example of FIG. 6B.

In the example of FIGS. 6A to 6C, the intaglio band 30 formed on the outer circumferential surface of the optical fiber unit may be formed in various numbers, and may have various shapes such as a spiral or a wave pattern on the outer circumferential surface of the protective layer, and may also be machined. It is a matter of course that the shape of the device can have a variety of cross-sectional shapes, such as triangular, semi-circular, circular arc, square.

In addition, although not shown, when a plurality of optical fibers 10 are used by the ribbon 16 as shown in Figures 6a to 6c, it is possible to install a tensile reinforcing member with the optical fiber. The tension reinforcing member may be additionally installed with the plurality of optical fibers 10 in the ribbon 16, or alternatively, some of the plurality of optical fibers tied to the ribbon 16 may be replaced with the tensile reinforcing members. . At this time, the tensile reinforcing member serves to reinforce the tensile strength of the optical fiber unit. The number of tensile reinforcing members can be changed in various ways depending on the use environment. In addition, fibers or wires may be used as the tensile reinforcing member, and it is preferable to use Kevlar fibers or Aramid fibers as the fibers.

Figure 7 shows a series of devices for manufacturing the optical fiber unit for pneumatic laying of the present invention. Looking at the apparatus for manufacturing the optical fiber unit of the present invention with reference to Figure 7 and the manufacturing process accordingly as follows.

In order to manufacture the optical fiber unit of the present invention, it is also possible to add only the equipment for forming a negative strip on the outer circumferential surface of the protective layer of the optical fiber unit in the state of using the existing general equipment. Therefore, the existing equipment in the following description will be briefly described, but focuses only on the process of forming the intaglio.

First, in order to manufacture the optical fiber unit of the present invention includes a payoff (60) for supplying the optical fiber and take-up (take-up; 100) device for winding it. In other words, the optical fiber is supplied through the payoff 60 to undergo a series of processes to be completed into the optical fiber unit, and then the completed optical fiber unit is wound around the take-up device 100.

The optical fiber supplied from the payoff 60 is first guided to the coating die 70. At this time, the guide roller 62 may be installed in the vicinity of the coating die 70 so that the optical fiber has an appropriate entry direction with respect to the coating die 70. The coating die 70 coats a protective layer such as a buffer layer or an outer skin layer on the surface of the optical fiber to make an optical fiber unit, and supplies the coated optical fiber unit to the ultraviolet curing device 80.

At this time, the protective layer coated on the surface of the optical fiber is in a considerably heated state, in which the operation such as surface processing is not easy. Accordingly, the ultraviolet curing device 80 supplies ultraviolet rays to the optical fiber unit to cure the coated protective layer. In this way, the optical fiber unit of which the protective layer is cured is supplied to the machining apparatus 90.

The machining device 90 forms the above-mentioned intaglio on the outer circumferential surface of the protective layer cured while the optical fiber unit is in progress. In this case, the machining apparatus 90 preferably uses a groove cutting method, for which a cutting tool having a specific shape is provided. In addition, in order to process the intaglio strip in a spiral or wavy pattern as shown in FIGS. 3 and 4, the machining apparatus 90 must be rotated in a predetermined manner, and the machining apparatus 90 includes a motor 92. Is connected. The motor 92 rotates the machining device 90 about the center of the optical fiber unit. In addition, the motor 92 may be connected to the control unit 94 to operate by a command of the control unit 94.

In this case, in order to process the spiral intaglio 30 shown in FIG. 3 on the outer circumferential surface of the optical fiber unit, the machining apparatus 90 only needs to be rotated in one direction. That is, since the optical fiber unit is continuously moving during the formation of the intaglio strip, when the groove cutting is performed while rotating the machining apparatus 90 at an appropriate speed, the spiral intaglio band 30 having the shape shown in FIG. 3 is formed. will be.

On the other hand, in order to process the wavy intaglio 40 as shown in Figure 4 on the outer peripheral surface of the optical fiber unit, the machining device 90 is rotated alternately clockwise and counterclockwise. Therefore, in this case, the motor 92 should be capable of forward and reverse rotation, and the rotation direction of the motor 92 may be changed by the condition set in the controller 94.

When the intaglio strip forming process is completed, the optical fiber unit of the present invention is completed, and the completed optical fiber unit is supplied to the take-up apparatus 100 and wound up.

As described above, although the present invention has been described by way of limited embodiments and drawings, the present invention is not limited thereto and is intended by those skilled in the art to which the present invention pertains. Various modifications and variations can be made within the equivalent scope of the utility model registration claims to be described.

The optical fiber unit for pneumatic laying according to the present invention as described above can increase the surface resistance with pneumatic by a simple process of forming a negative strip on the outer circumferential surface of the protective layer surrounding the optical fiber to improve the efficiency of pneumatic laying. The advantage is that it can be increased.

In addition, the optical fiber unit of the present invention is very productive because there is no need for cumbersome processes such as mixing and coating fine particles used in the conventional polymer resin or attaching the fine particles to the surface of the uncured polymer resin. Problems such as crack generation due to defects between fine particles and crack propagation into the optical fiber unit are greatly reduced.

In addition, the optical fiber unit of the present invention prevents thermal cracking caused by the difference in thermal strain coefficient between the fine particles such as glass beads and the resin, and solves the problem that glass beads are broken in the optical fiber unit.

When the optical fiber unit is manufactured using the manufacturing apparatus of the present invention, the process of coating or externally attaching the fine particles can be eliminated, thereby reducing material costs and manufacturing costs, and preventing deterioration of the working environment by the fine particles.

In addition, the present invention is made by a mechanical method immediately after the outer protective layer of the polymer material is hardened by the surface morphology suitable for pneumatic installation, the manufacturing process is very simple. In addition, since the optical fiber unit does not cause problems such as breakage or peeling of particles even during the storage and installation process, the optical fiber unit can be safely and conveniently performed compared to the existing product.

Claims (22)

Optical fiber; And A protective layer surrounding the optical fiber, At least one intaglio band is formed on the outer circumferential surface of the protective layer in the longitudinal direction of the protective layer. The method of claim 1, The intaglio band is formed in a spiral on the outer peripheral surface of the protective layer, the optical fiber unit for pneumatic installation. The method of claim 1, The intaglio band is a pneumatic optical fiber unit, characterized in that formed in a wavy pattern on the outer peripheral surface of the protective layer. The method of claim 1, Cross section of the intaglio band is blunt triangle, semi-circular, arc-shaped or square end of the pneumatic laying optical fiber unit. The method of claim 1, And the plurality of optical fibers, and the plurality of optical fibers in the form of a ribbon in the protective layer. The method of claim 5, In the protective layer, a tensile reinforcing member for reinforcing tensile strength is present in the form of a ribbon together with the plurality of optical fibers optical fiber unit for pneumatic installation. The method of claim 6, The tensile reinforcing member is any one of Kevlar fiber, Aramid fiber and wire, the optical fiber unit for pneumatic installation. The method according to any one of claims 1 to 7, The optical fiber unit for air pressure installation, characterized in that the optical fiber is any one of a quartz optical fiber and a plastic optical fiber. The method according to any one of claims 1 to 7, And the protective layer is a buffer layer. The method of claim 9, The buffer layer includes a plurality of hollow spheres in the form of particulates for weight reduction, wherein the hollow spheres are formed so as not to affect the outer shape of the protective layer. The method of claim 9, The buffer layer is a pneumatic laying optical fiber unit, characterized in that it has a strain Secant Modulus of 400MPa ~ 1000MPa at 2.5% strain. The method according to any one of claims 1 to 7, The protective layer is a pneumatic laying optical fiber unit, characterized in that consisting of a buffer layer and an outer shell layer. The method of claim 12, The envelope layer has a secant modulus of 400 MPa to 1000 MPa at 2.5% strain. The method of claim 12, The envelope layer has a secant modulus of 500 MPa to 800 MPa at 2.5% strain. The method according to any one of claims 1 to 7, The protective layer is a pneumatic laying optical fiber unit, characterized in that consisting of a buffer layer, an intermediate layer and an outer shell layer. Means for supplying an optical fiber unit having at least one optical fiber and at least one protective layer surrounding the optical fiber; Machining means for forming one or more intaglio bands along the longitudinal direction of the protective layer on the outer peripheral surface of the protective layer of the supplied optical fiber unit; And And a take-up means for winding the optical fiber unit processed by the machining means. The method of claim 16, The machining means is connected to a motor providing a one-way rotational force, the machining means is rotated in one direction by the motor while the optical fiber unit is in progress to form a spiral intaglio on the outer peripheral surface of the protective layer The manufacturing apparatus of the optical fiber unit for pneumatic laying. The method of claim 16, The machining means is connected to a motor providing a bidirectional rotational force, the machining means is rotated alternately clockwise and counterclockwise by the motor while the optical fiber unit is in progress, the wave pattern on the outer peripheral surface of the protective layer Apparatus for manufacturing a pneumatic fiber optical unit, characterized in that forming an intaglio. The method of claim 18, And a control means connected to the motor to control the rotation direction and the rotation angle of the motor by a preset value. The method according to any one of claims 16 to 19, For the pneumatic installation, characterized in that it further comprises a guide roller provided between the optical fiber unit supply means and the machining means and between the machining means and the take-up means, respectively, for adjusting the conveying direction of the optical fiber unit. Apparatus for manufacturing an optical fiber unit. The method according to any one of claims 16 to 19, And said optical fiber unit supply means is a pay-off means for supplying an optical fiber unit in which an optical fiber and a protective layer are formed in advance. The optical fiber unit supply means according to any one of claims 16 to 19, Pay-off means for supplying at least one optical fiber; A coating die forming at least one protective layer around the optical fiber; And And an ultraviolet curing means for curing the protective layer by providing ultraviolet rays to the coated optical fiber.