Patent Description:
The present disclosure relates to the field of anti-termite air-blown optical cables, and particularly to a superfine anti-termite air-blown optical cable and a fabrication method thereof.

With the continuous development of network technology, as a communication mode with the highest speed and the best transmission quality, the optical fiber communication is widely used. An optical cable is generally constituted mainly by optical fibers (glass filaments as thin as hair), a plastic protective sleeve and a plastic sheath. The optical cable does not contain metal such as gold, silver, copper and aluminum, and therefore is of no recycling value. In communication construction, communication lines often pass through some areas where termites are active, traditional optical cables are easily nibbled by termites, and finally the optical fibers in the optical cables are broken and communication is interrupted. Therefore, anti-termite optical cables are required.

The conventional anti-termite optical cable <NUM> is generally the GYTS04 type optical cable, which is a layer stranded optical cable with a structure as shown in <FIG>, comprising a cable core, and a plastic-coated steel strip <NUM> and an outer sheath sequentially sleeved outside the cable core, wherein the outer sheath is a double-layered outer sheath: a first outer sheath <NUM> and a second outer sheath <NUM>, the cable core comprises a central reinforcing body <NUM>, and a plurality of loose tubes <NUM> and cables <NUM> arranged around the central reinforcing body, a plurality of optical fibers <NUM> are wrapped in the loose tubes <NUM>, the space between the optical fibers <NUM> and the loose tubes <NUM> is filled with a fiber paste <NUM>, and the space among the loose tubes <NUM>, the cables <NUM> and the plastic-coated steel strip <NUM> is filled with a cable paste <NUM>. In order to ensure the strength of the optical cable, there are provided a central reinforcing body <NUM>, and loose tubes <NUM> and cables <NUM> uniformly disposed around the central reinforcing body <NUM>; and in order to ensure the anti-termite effect, the outer sheath of the optical fibers is provided with a multi-layered structure layer. In the actual use process, the optical cable has a relatively large outer diameter, needs to occupy a relatively large space due to the limitation of the dimension of the minimum installation bending radius, and can be laid in limited scenarios.

With the increasing shortage of pipeline resources and due to the need of anti-termite performance, a superfine anti-termite air-blown optical cable is required to solve the above-mentioned problems. Publication <CIT> discloses an optical fiber cable that comprises a loose sleeve in the center and a plurality of glass optical fibers inside the loose sleeve, wherein thixotropic water-proof fiber paste is filled between the loose sleeve and the glass optical fibers.

The invention provides a superfine anti-termite air-blown optical cable according to independent claim <NUM> and a method for fabricating a superfine anti-termite air-blown optical cable according to independent claim <NUM>. Further embodiments are provided by the dependent claims.

The advantageous effects of the embodiments of the present disclosure include: the superfine anti-termite air-blown optical cable of the embodiments of the present disclosure has a high optical fiber density, a small outer diameter, saves laying space and meets the requirement of anti-termite performance. The method for fabricating the superfine anti-termite air-blown optical cable of the embodiments of the present disclosure is a simple method.

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, brief description is made below on the drawings required to be used in the embodiments. It should be understood that the following drawings only illustrate some of the embodiments of the present disclosure and thus shall not be regarded as a limitation to the scope, and for a person of ordinary skills in the art, other related drawings may be obtained from these drawings without inventive effort.

Reference signs: <NUM>-anti-termite optical cable; <NUM>-central reinforcing body; <NUM>-loose tube; <NUM>-optical fiber; <NUM>-fiber paste; <NUM>-cable; <NUM>-cable paste; <NUM>-plastic-coated steel strip; <NUM>-first outer sheath; <NUM>-second outer sheath; <NUM>-superfine anti-termite air-blown optical cable; <NUM>-glass optical fiber; <NUM>-waterproof fiber paste; <NUM>-loose tube; <NUM>-waterproof aramid fiber; <NUM>-outer sheath; <NUM>-superfine anti-termite air-blown optical cable; <NUM>-waterproof yarn; <NUM>-superfine anti-termite air-blown optical cable; and <NUM>-air-blowing groove.

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be described clearly and completely below with reference to the drawings of the embodiments of the present disclosure. Apparently, the embodiments described are some of the embodiments of the present disclosure, rather than all of the embodiments. The components of the embodiments of the present disclosure described and illustrated in the drawings herein can generally be arranged and designed in a variety of different configurations.

It should be noted that like reference signs and letters denote like items in the following drawings, and therefore, once a certain item is defined in one figure, it does not need to be further defined or explained in the following figures.

In the description of the present disclosure, it should be noted that the orientation or position relation denoted by the terms such as "center", "inner" and "outer" is based on the orientation or position relation indicated by the figures, or refers to the orientation or position relation where the product of the present disclosure is normally placed when in use, which only serves to facilitate describing the present disclosure and simplify the description, rather than indicating or suggesting that the device or element referred to must be in a particular orientation, or is constructed or operated in a particular orientation, and therefore cannot be construed as a limitation on the present disclosure.

In the description of the present disclosure, it should be further noted that unless otherwise explicitly specified and defined, the term "arrange" shall be understood in broad sense, which may, for example, refer to fixed connection, detachable connection or integral connection; may refer to mechanical connection or electrical connection; may refer to direct connection or indirect connection by means of an intermediate medium; and may refer to internal communication between two elements. A person of ordinary skills in the art could understand the specific meaning of the above term in the present disclosure according to specific situations.

Referring to <FIG>, the present embodiment provides a superfine anti-termite air-blown optical cable <NUM>, i.e., the GCYFXT04 type optical cable, which comprises a loose tube <NUM> located in the center and an outer sheath <NUM> sleeved on the loose tube <NUM>, a plurality of colored glass optical fibers <NUM> being wrapped in the loose tube <NUM>, waterproof fiber paste <NUM> being filled between the glass optical fibers <NUM> and the loose tube <NUM>, and a plurality of waterproof aramid fibers <NUM> being arranged between the loose tube <NUM> and the outer sheath <NUM>. The superfine anti-termite air-blown optical cable <NUM> of the present embodiment is a center beam tube type optical cable, which is specifically formed by adding waterproof aramid fibers <NUM> armor to the exterior of the center beam tube type loose tube <NUM> and then using a high-hardness outer sheath <NUM>. The superfine anti-termite air-blown optical cable <NUM> has only two structural layers sleeved outside the glass optical fibers <NUM>, has a high optical fiber density and a small outer diameter, which saves the laying space; the optical cable has good bending performance and a light weight, and can be laid more rapidly and conveniently; and the waterproof fiber paste <NUM> and waterproof aramid fibers <NUM> work together to meet the requirements of waterproof and tensile properties.

In the present embodiment, the glass optical fiber <NUM> may be a single-mode optical fiber or a multimode optical fiber.

In the present embodiment, the waterproof fiber paste <NUM> is a thixotropic waterproof fiber paste <NUM> formed by mixing a base oil and a gelling agent, which was specifically purchased from the finished products produced by Shenzhen Xinchanglong New Material Technology Co.

In addition, the exterior of the outer sheath may be coated with a water-resistant polyurethane sheath, which can add a waterproof function to the exterior of the outer sheath, and improves the waterproof performance.

Optionally, the waterproof fiber paste <NUM> is a thixotropic waterproof fiber paste <NUM> formed by mixing a base oil and a gelling agent, wherein the gelling agent may be a gel in which colloidal particles or polymers in a sol or solution are connected to each other under certain conditions to form a space network structure, wherein the gap in the structure is filled with a liquid serving as a dispersion medium, wherein the liquid may be a gas in the case of xerogel, and xerogel is also referred to as an aerogel.

According to the claimed \invention, the gelling agent is a hot melt adhesive, and the hot melt adhesive is an adhesive with plasticity, whose physical state changes with the change of temperature within a certain temperature range, and whose chemical characteristics do not change; and then the waterproof fiber paste <NUM> is formed by using the hot melt adhesive and the base oil to fill the gap between the glass optical fibers <NUM> and the loose tube <NUM>, which improves the overall performance of the optical cable, realizes the small outer diameter and light weight of the optical cable, improves the stability of the optical cable, and is also more user-friendly.

In the present embodiment, the loose tube <NUM> is a double-layered co-extruded sleeve, specifically made by co-extrusion of polycarbonate and polybutylene terephthalate. In the present embodiment, the loose tube <NUM> of a <NUM>-core superfine anti-termite air-blown optical cable <NUM> has an outer diameter of <NUM>-<NUM>; the loose tube <NUM> of a <NUM>-core superfine anti-termite air-blown optical cable <NUM> has an outer diameter of <NUM>-<NUM>; and both the loose tubes <NUM> have a thickness of <NUM>-<NUM>.

In the present embodiment, the waterproof aramid fibers <NUM> have a linear density of <NUM>-<NUM> dtex, in the number of <NUM>-<NUM>. The pay-off mode is straight pay-off, i.e., arranged in the axial direction.

In the present embodiment, the outer sheath <NUM> is a nylon sheath, preferably nylon <NUM> which is a high-hardness sheath material, with excellent anti-termite effect. In the present embodiment, the outer sheath <NUM> of the <NUM>-core superfine anti-termite air-blown optical cable <NUM> has an outer diameter of <NUM>-<NUM>; the outer sheath <NUM> of the <NUM>-core superfine anti-termite air-blown optical cable <NUM> has an outer diameter of <NUM>-<NUM>; and both the outer sheaths <NUM> have a thickness of <NUM>-<NUM>.

Compared with the conventional anti-termite optical cable <NUM>, the superfine anti-termite air-blown optical cable <NUM> of the present embodiment has a small outer diameter and a light weight, and the typical parameters of the superfine anti-termite air-blown optical cable <NUM> are shown in the table below:.

Referring to <FIG>, the present embodiment further provides a method for fabricating the above-described superfine anti-termite air-blown optical cable <NUM>, comprising the steps of:.

When the above-described method is used to fabricate the superfine anti-termite air-blown optical cable <NUM>, a plurality of waterproof aramid fibers <NUM> are distributed between the loose tube <NUM> and the outer sheath <NUM>, which can enhance the tensile performance of the optical cable and improve the waterproof performance; the optical cable has a small outer diameter and good resistance to side pressure; and the optical cable has a light weight, and compared with the conventional GYTS04 structure, the outer diameter of the optical cable is reduced by <NUM>% and the weight is reduced by <NUM>%, which reduces the material consumption, reduces the product cost, and facilitates the promotion and the application of the product.

Referring to <FIG>, the present embodiment, not forming part of the claimed invention, provides a superfine anti-termite air-blown optical cable <NUM>, i.e., the GCYFX04 type optical cable. The superfine anti-termite air-blown optical cable <NUM> has substantially the same structure as the superfine anti-termite air-blown optical cable <NUM> of the first embodiment except that waterproof yarns <NUM> are filled between the glass optical fibers <NUM> and the loose tube <NUM>.

In the present embodiment, the waterproof yarns <NUM> have a linear density of <NUM>-<NUM> dtex, in the number of <NUM>-<NUM>, which are properly adjusted according to the size of the outer sleeve, and the pay-off mode is straight pay-off, i.e., arranged in the axial direction.

The typical parameters of the superfine anti-termite air-blown optical cable <NUM> are shown in the table below:.

The present embodiment, not forming part of the claimed invention, further provides a method for fabricating the above-described superfine anti-termite air-blown optical cable <NUM>. The fabrication method is substantially the same as the fabrication method of the first embodiment except the step c. plastic shield prebalelling: placing colored glass optical fibers <NUM> and the waterproof yarns <NUM> simultaneously in a high-modulus loose tube <NUM>, and enabling stable control on surplus length of the glass optical fibers <NUM> in the loose tube <NUM> and transmission of the glass optical fibers <NUM> characteristic by controlling pay-off speed and water tank temperature.

Referring to <FIG>, the present embodiment provides a superfine anti-termite air-blown optical cable <NUM>, which is substantially the same as that of the first embodiment, except that the outer surface of the outer sheath <NUM> is provided with a plurality of air-blowing grooves <NUM> arranged in the axial direction. The outer surface of the superfine anti-termite air-blown optical cable <NUM> is provided with air-blowing grooves <NUM> to facilitate the implementation of air-blowing laying process, which is specifically as follows:
a cable blowing machine is communicated with one end of a core tube, a high pressure air flow is blown into the core tube by the cable blowing machine, and the high pressure air flow feeds the superfine anti-termite air-blown optical cable <NUM> into the core tube, the air-blowing grooves <NUM> on the outer surface of the superfine anti-termite air-blown optical cable <NUM> can increase the contact area between the optical cable and the air flow so as to improve the air-blowing effect.

In summary, the superfine anti-termite air-blown optical cable of the embodiments of the present disclosure is a center beam tube type optical cable, which has a high optical fiber density, a small outer diameter, saves laying space and meets the requirement of anti-termite performance. The method for fabricating the superfine anti-termite air-blown optical cable of the embodiments of the present disclosure is simple.

Claim 1:
A superfine anti-termite air-blown optical cable (<NUM>; <NUM>), comprising a loose tube (<NUM>) located in a center of the optical cable (<NUM>; <NUM>) and an outer sheath (<NUM>) sleeved on the loose tube (<NUM>), wherein a plurality of colored glass optical fibers (<NUM>) are wrapped in the loose tube (<NUM>), a thixotropic waterproof fiber paste (<NUM>) is filled between the glass optical fibers (<NUM>) and the loose tube (<NUM>), and a plurality of waterproof aramid fibers (<NUM>) are arranged between the loose tube (<NUM>) and the outer sheath (<NUM>), characterized in that the thixotropic waterproof fiber paste (<NUM>) is formed from a hot melt adhesive and a base oil mixed.