Central tube type optical cable
By reinforcing the design of the yarn layer and outer sheath in the central tube optical cable, combined with the partial embedding of the reinforcement and the connection of the viscose layer, the problems of insufficient flexibility and tensile strength of the optical cable are solved, and the high and low temperature performance of the optical cable and the convenience of construction are improved.
Patent Information
- Application Number
- CN202422746311.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-11
- Publication Date
- 2025-09-05
- Estimated Expiration
- 2034-11-11
AI Technical Summary
While the existing central tube access optical cable maintains tensile strength, it lacks flexibility and is easily broken by artificial bending during construction, thereby reducing tensile strength.
A reinforcing yarn layer is used to cover the outer edge of the loose tube, and an outer sheath covers the reinforcing yarn layer. A reinforcing member is partially embedded in the outer sheath, and partially exposed to contact the reinforcing yarn layer. The reinforcing member is tightly connected to the sheath through a viscose layer to form an extrusion force to suppress the displacement of the loose tube.
It improves the overall structural stability and flexibility of the optical cable, reduces the wall thickness of the optical cable, reduces the manufacturing cost, and enhances the high and low temperature performance and construction convenience of the optical cable.
Smart Images
Figure CN223308437U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of communication optical cables, and in particular to a central tube optical cable. Background Art
[0002] In access networks, non-twisted optical cables with single loose tube subunits are called central tube access cables. Common installation methods include overhead and duct installation. Aerial applications typically involve attaching cables to utility poles for wiring, and can be used for both short-distance access and long-distance aerial applications.
[0003] Common central tube access cables have two or more parallel reinforcements embedded in their sheaths. This structure enhances the cable's tensile strength through rigid load-bearing elements and inhibits longitudinal contraction. However, it also restricts the cable's bending direction, reducing its flexibility. Improper bending during construction can also cause the reinforcements to break, reducing the cable's tensile strength. Summary of the Invention
[0004] In response to the deficiencies or one of the deficiencies raised in the above-mentioned background technology, the embodiments of the present application provide a central tube optical cable that can maintain good tensile strength and low shrinkage performance, while improving the flexibility of the optical cable and enhancing the extraction force value of the optical cable sheath.
[0005] The present invention provides a central tube optical cable, comprising:
[0006] loose tube;
[0007] a reinforcing yarn layer, which is coated on the outer edge of the loose tube;
[0008] an outer sheath covering the outer edge of the reinforcing yarn layer;
[0009] A reinforcement member is partially embedded in the outer sheath and partially exposed from the outer sheath at any cross section, and the portion of the reinforcement member exposed from the outer sheath contacts the reinforcing yarn layer to press the reinforcing yarn layer onto the loose tube.
[0010] In some embodiments, an optical fiber is disposed in the loose tube, and a water-blocking filler is filled between the loose tube and the optical fiber.
[0011] In some embodiments, the reinforcing yarn layer is composed of multiple strands of reinforcing yarns, and the reinforcing yarns are glass fiber yarns or aramid fiber yarns.
[0012] In some embodiments, the reinforcement is continuously spirally wound on the reinforcing yarn layer along the extension direction of the loose tube.
[0013] In some embodiments, there are two reinforcing members, the two reinforcing members are wound around the reinforcing yarn layer along the same spiral direction, and a center line connecting the two reinforcing members passes through the center of the loose tube.
[0014] In some embodiments, there are multiple reinforcement members, and the multiple reinforcement members are wound on the reinforcing yarn layer along the same spiral direction to form an armor layer for protecting the loose tube.
[0015] In some embodiments, the outer surface of the reinforcement is coated with an adhesive layer for bonding to the outer sheath, and the adhesive layer is ethylene ethyl acrylate copolymer.
[0016] In some embodiments, the ratio of the cross-sectional area of the reinforcement embedded in the outer sheath at any cross-section to the total cross-sectional area of the reinforcement is greater than or equal to 50%.
[0017] In some embodiments, the reinforcement is a fiber reinforced plastic rod, the tensile strength of the reinforcement is greater than or equal to 1100 MPa, and the tensile elastic modulus of the reinforcement is greater than or equal to 50 GPa.
[0018] In some embodiments, a tear cord for stripping the outer sheath is spirally wound between the outer sheath and the reinforcing yarn layer.
[0019] The beneficial effects of the technical solution provided by this application include:
[0020] An embodiment of the present application provides a central tube optical cable, in which the reinforcing yarn layer is covered on the outer edge of the loose tube, the outer sheath is covered on the outer edge of the reinforcing yarn layer, and at the same time, the reinforcing member is partially embedded in the outer sheath and partially exposed from the outer sheath at any cross-section. The portion of the reinforcing member exposed from the outer sheath contacts the reinforcing yarn layer to press the reinforcing yarn layer tightly against the loose tube.
[0021] Therefore, a part of the reinforcement abuts against the reinforcing yarn layer, generating corresponding extrusion pressure on the reinforcing yarn layer and the loose tube, which can suppress the relative displacement of the loose tube in the outer sheath, increase the extraction force value of the outer sheath, improve the overall structural stability of the optical cable, suppress the longitudinal shrinkage of the optical cable, and improve the high and low temperature performance of the optical cable.
[0022] Compared to optical cables with reinforcement members completely embedded in the outer sheath, the structure with reinforcement members partially embedded in the outer sheath can reduce the wall thickness of the optical cable, thereby reducing the overall size of the optical cable, reducing the amount of reinforcement yarn used, and reducing the manufacturing cost of the optical cable. In addition, the optical cable of the present application can be formed by a single sheath extrusion, which has the advantage of convenient production and manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.
[0024] Figure 1 A schematic cross-sectional view of a central tube optical cable provided in an embodiment of the present application;
[0025] Figure 2 Schematic diagram of the connection between the reinforcement member and the reinforcing yarn layer provided in an embodiment of the present application.
[0026] In the accompanying drawings, the components represented by the reference numerals are as follows:
[0027] 101. Loose tube; 102. Reinforcement yarn layer; 103. Outer sheath; 104. Reinforcement member; 105. Optical fiber; 106. Water-blocking filler; 107. Rip cord. DETAILED DESCRIPTION
[0028] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0029] In response to the deficiencies or one of the deficiencies raised in the above-mentioned background technology, the embodiments of the present application provide a central tube optical cable that can maintain good tensile strength and low shrinkage performance, while improving the flexibility of the optical cable and enhancing the extraction force value of the optical cable sheath.
[0030] See also Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable, comprising:
[0031] Loose tube 101;
[0032] a reinforcing yarn layer 102 , which is wrapped around the outer edge of the loose tube 101 ;
[0033] an outer sheath 103 covering the outer edge of the reinforcing yarn layer 102;
[0034] The reinforcement 104 is partially embedded in the outer sheath 103 and partially exposed from the outer sheath 103 at any cross section. The portion of the reinforcement 104 exposed from the outer sheath 103 contacts the reinforcing yarn layer 102 to press the reinforcing yarn layer 102 onto the loose tube 101 .
[0035] The central tube optical cable of an embodiment of the present application includes a loose tube 101, a reinforcing yarn layer 102, an outer sheath 103 and a strength member 104. The reinforcing yarn layer 102 is covered on the outer surface of the loose tube 101, and the outer sheath 103 is covered on the outer surface of the reinforcing yarn layer 102. The strength member 104 is partially embedded in the outer sheath 103 and partially exposed to the inner wall of the outer sheath 103 at any cross section. The portion of the strength member 104 exposed from the outer sheath 103 abuts against the reinforcing yarn layer 102.
[0036] Under the action of the outer sheath 103, the reinforcement 104 can generate corresponding extrusion pressure on the reinforcing yarn layer 102 and the loose tube 101, thereby suppressing the relative displacement of the loose tube 101 in the outer sheath 103, increasing the extraction force value of the outer sheath 103, and improving the overall structural stability of the optical cable, thereby suppressing the longitudinal shrinkage of the optical cable and improving the high and low temperature performance of the optical cable.
[0037] Compared to optical cables in which the reinforcement members 104 are completely embedded in the outer sheath 103, the structure in which the reinforcement members 104 are partially embedded in the outer sheath 103 can reduce the wall thickness of the optical cable, thereby reducing the overall size of the optical cable, reducing the amount of reinforcing yarn used, and reducing the manufacturing cost of the optical cable. In addition, the optical cable of the present application can be formed by a single sheath extrusion, which has the advantage of convenient production and manufacturing.
[0038] For example, the optical cable body of the embodiment of the present application includes an outer sheath 103 having a thickness of 1.0 mm to 2.0 mm. When the optical cable is used outdoors, the sheath material can be high-density polyethylene (HDPE). When the application environment requires flame retardancy, the sheath material can be low-smoke halogen-free flame-retardant polyolefin (LSZH) to facilitate high-temperature extrusion molding.
[0039] The inner side of the reinforcing yarn layer 102 is covered with a loose tube 101. The diameter of the loose tube 101 is 1.2 mm to 3.6 mm. The loose tube 101 is made of one of polybutylene terephthalate (PBT), polycarbonate (PC), and polyester-based thermoplastic elastomer (TPEE).
[0040] Alternatively, the loose tube 101 may be co-extruded from PBT and PC to form a double-layer loose tube, with the ratio of PBT to PC being 1:2. Alternatively, the loose tube 101 may be co-extruded from PBT and TPEE to form a double-layer loose tube, with the ratio of PBT to TPEE being 1:2.
[0041] A portion of the strength member 104 abuts against the reinforcing yarn layer 102, exerting a corresponding compressive force on the reinforcing yarn layer 102 and the loose tube 101. This suppresses the relative displacement of the loose tube 101 within the outer sheath 103, increases the sheath extraction force, and improves the overall structural stability of the optical cable. In the embodiment, the optical cable was subjected to a sheath extraction test in accordance with Appendix F of YD / T 1258.2-2009, and the force required to extract 10 cm of sheath from the cable core was greater than or equal to 50N.
[0042] In some alternative embodiments: See Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable, in which an optical fiber 105 is arranged in a loose tube 101 of the central tube optical cable, and a water-blocking filler 106 is filled between the loose tube 101 and the optical fiber 105 .
[0043] The inner cavity of the loose tube 101 of the present embodiment is provided with an optical fiber 105 and a water-blocking filler 106. Exemplarily, the optical fiber 105 is a bare optical fiber 105 or a colored optical fiber 105. When the number of optical fibers 105 exceeds 12, the optical fibers 105 can be identified by a spray ring on the surface of the optical fibers 105. The water-blocking filler 106 can be a fiber paste, which is a thixotropic gel. To ensure a water-blocking effect, the fiber paste filling degree in the loose tube 101 is greater than or equal to 85%.
[0044] In some alternative embodiments: See Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable, wherein the reinforcing yarn layer 102 of the central tube optical cable is composed of multiple strands of reinforcing yarns, and the reinforcing yarns are glass fiber yarns or aramid fiber yarns.
[0045] The reinforcing yarn layer 102 of the embodiment of the present application is composed of multiple strands of reinforcing yarn, which are evenly wrapped on the outer surface of the loose tube 101. The reinforcing yarn is made of either glass fiber yarn or aramid fiber yarn, or a mixture of the two materials, and is spirally wrapped with a certain twist pitch.
[0046] In some other embodiments, the multiple strands of reinforcing yarns may be arranged flatly on the outer surface of the loose tube 101. In addition, to improve the water-blocking performance of the reinforcing yarn layer 102, the gaps formed by the multiple strands of reinforcing yarns may be filled with water-absorbing powder.
[0047] In some alternative embodiments: See Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable, in which a strength member 104 is continuously spirally wound on a reinforcing yarn layer 102 along an extending direction of a loose tube 101 .
[0048] A reinforcement member 104 is provided between the outer sheath 103 and the reinforcement yarn layer 102 of the embodiment of the present application. The reinforcement member 104 is spirally wrapped on the reinforcement yarn layer 102, so that the optical cable can be easily bent in any direction, the flexibility of the optical cable is improved, and it is convenient for construction personnel to perform installation operations.
[0049] In some alternative embodiments: See Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable, which has two strength members 104 , which are wound on the reinforcing yarn layer 102 along the same spiral direction, and the center line connecting the two strength members 104 passes through the center of the loose tube 101 .
[0050] Two reinforcement members 104 are provided between the outer sheath 103 and the reinforcing yarn layer 102 in the embodiment of the present application. These members 104 are arranged at equal intervals. Specifically, in this embodiment, the two reinforcement members 104 are arranged at a 180° angle. The reinforcement members 104 are helically wrapped in the same direction along the axis of the outer sheath 103 at a predetermined twist pitch. Since the reinforcement members 104 are helically wrapped within the interior of the optical cable, the cable can be easily bent in any direction, improving its flexibility and facilitating installation operations for construction personnel.
[0051] In some alternative embodiments: See Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable having a plurality of strength members 104 , which are wound on the reinforcing yarn layer 102 along the same spiral direction to form an armor layer for protecting the loose tube 101 .
[0052] In the embodiment of the present application, a plurality of reinforcement members 104 are provided between the outer sheath 103 and the reinforcing yarn layer 102. The plurality of reinforcement members 104 are spirally wrapped in the same direction along the axis of the outer sheath 103, so as to completely cover the loose tube 101 and form an armor layer, so that the optical cable has excellent lateral pressure resistance and certain anti-rodent performance.
[0053] In some alternative embodiments: See Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable, wherein the outer surface of the strength member 104 of the central tube optical cable is coated with an adhesive layer for bonding the outer sheath 103 , and the adhesive layer is ethylene ethyl acrylate copolymer.
[0054] The outer surface of the strength member 104 of the embodiment of the present application is coated with an adhesive layer, which can tightly adhere the outer sheath 103 and the strength member 104 together, thereby suppressing the longitudinal shrinkage of the optical cable and improving the high and low temperature performance of the optical cable.
[0055] Exemplarily, the outer periphery of reinforcement 104 is coated with a low-melting-point copolymer adhesive. The diameter of reinforcement 104 containing the copolymer adhesive is greater than or equal to 0.58 mm. The copolymer adhesive is ethylene ethyl acrylate (EEA). Under the high temperature of the sheath material, the EEA adhesive melts, tightly adhering reinforcement 104 and the sheath material together. Under pressure from the extruder die, a portion of reinforcement 104 is embedded in the sheath, while the remaining portion abuts the reinforcing yarn.
[0056] The partial embedding of the strength members 104 into the outer sheath 103 can suppress longitudinal shrinkage of the cable sheath and improve the cable's high and low temperature performance. Compared to central tube optical cables in which the strength members 104 are completely embedded in the outer sheath 103, this structure can reduce the cable wall thickness, thereby reducing the overall size of the cable, reducing the amount of reinforcing yarn used, and lowering the manufacturing cost of the cable.
[0057] In some alternative embodiments: See Figure 1 and Figure 2 As shown, the embodiment of the present application provides a central tube optical cable, in which the ratio of the cross-sectional area of the reinforcing member 104 embedded in the outer sheath 103 at any cross section to the total cross-sectional area of the reinforcing member 104 is greater than or equal to 50%.
[0058] In the embodiment of the present application, the ratio of the cross-sectional area of the reinforcement member 104 embedded in the outer sheath 103 at any cross-section to the total cross-sectional area of the reinforcement member 104 is greater than or equal to 50%. This ensures that the connection strength between the reinforcement member 104 and the outer sheath 103 is effectively guaranteed under the premise that the reinforcement member 104 is partially embedded in the outer sheath 103, thereby suppressing the longitudinal shrinkage of the optical cable sheath and improving the high and low temperature performance of the optical cable.
[0059] In some alternative embodiments: See Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable, wherein the reinforcement member 104 of the central tube optical cable is a fiber reinforced plastic rod, the tensile strength of the reinforcement member 104 is greater than or equal to 1100 MPa, and the tensile elastic modulus of the reinforcement member 104 is greater than or equal to 50 GPa.
[0060] In the embodiment of the present application, a reinforcement member 104 is provided between the outer sheath 103 and the reinforcing yarn layer 102. The reinforcement member 104 is a fiber-reinforced plastic rod having a large tensile strength and tensile elastic modulus, which can ensure the tensile performance of the optical cable and the stability of overhead applications.
[0061] For example, the reinforcement 104 can be made of glass fiber reinforced plastic (GFRP) or aramid fiber reinforced plastic (KFRP). The number of reinforcements 104 is two or more. The reinforcement 104 has a tensile strength of 1100 MPa or greater and a tensile modulus of 50 GPa or greater.
[0062] In some alternative embodiments: See Figure 1 and Figure 2 As shown, an embodiment of the present application provides a central tube optical cable, in which a tear rope 107 for stripping the outer sheath 103 is spirally wound between the outer sheath 103 and the reinforcing yarn layer 102 of the central tube optical cable.
[0063] In the embodiment of the present application, a rip cord 107 is provided between the outer jacket 103 and the reinforcing yarn layer 102. Rip cord 107 is used to strip the outer jacket 103 of the optical cable. One or two rip cords 107 are provided. When two rip cords 107 are provided, the angle between the two rip cords 107 is between 120° and 180°. The rip cords 107 are helically wrapped in the same direction along the jacket axis at a predetermined twist pitch. The rip cords 107 and the reinforcement member 104 have the same twist pitch and are wrapped in the same direction.
[0064] In summary, compared with the prior art, this application has the following advantages:
[0065] (1) At least 50% of the strength members 104 are embedded in the outer sheath 103 and are tightly bonded to the sheath material via the adhesive layer, which can inhibit the longitudinal shrinkage of the optical cable and improve the high and low temperature performance of the optical cable. Compared with optical cables in which the strength members 104 are completely embedded in the outer sheath 103, the structure in which the strength members 104 are partially embedded in the outer sheath 103 can reduce the wall thickness of the optical cable, thereby reducing the overall size of the optical cable, reducing the amount of reinforcing yarn used, and reducing the manufacturing cost of the optical cable.
[0066] (2) The reinforcement members 104 are spirally wrapped around the interior of the optical cable, making it easy to bend the cable in any direction. This improves the flexibility of the cable and facilitates installation by construction personnel. The use of multiple reinforcement members 104 enhances the tensile strength of the optical cable and the stability of the overhead application. When the number of reinforcement members 104 is large enough to completely cover the loose tube 101, a layer of armor can be formed, giving the optical cable excellent lateral pressure resistance and certain rodent protection.
[0067] (3) A portion of the reinforcement 104 abuts against the reinforcing yarn layer 102, generating a corresponding extrusion force on the reinforcing yarn layer 102 and the loose tube 101, thereby suppressing the relative displacement of the loose tube 101 in the outer sheath 103, increasing the extraction force value of the outer sheath 103, and improving the overall structural stability of the optical cable.
[0068] (4) The optical cable of this embodiment can be formed by extrusion of the sheath once, and the production is convenient.
[0069] In the description of this application, it should be noted that the terms "upper" and "lower" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.
[0070] It should be noted that, in this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.
[0071] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.
Claims
1. A central tube optical cable, characterized in that: include: Loose tube (101); a reinforcing yarn layer (102) covering the outer edge of the loose tube (101); an outer sheath (103) covering the outer edge of the reinforcing yarn layer (102); A reinforcement member (104) is partially embedded in the outer sheath (103) and partially exposed from the outer sheath (103) at any cross section, and the portion of the reinforcement member (104) exposed from the outer sheath (103) contacts the reinforcing yarn layer (102) to press the reinforcing yarn layer (102) onto the loose tube (101).
2. The central tube optical cable according to claim 1, wherein: An optical fiber (105) is arranged in the loose tube (101), and a water-blocking filler (106) is filled between the loose tube (101) and the optical fiber (105).
3. The central tube optical cable according to claim 1, wherein: The reinforcing yarn layer (102) is composed of multiple strands of reinforcing yarns, and the reinforcing yarns are glass fiber yarns or aramid fiber yarns.
4. The central tube optical cable according to claim 1, wherein: The reinforcement member (104) is continuously spirally wound on the reinforcing yarn layer (102) along the extension direction of the loose tube (101).
5. The central tube optical cable according to claim 1, wherein: There are two reinforcing members (104), which are wound on the reinforcing yarn layer (102) along the same spiral direction, and a center line connecting the two reinforcing members (104) passes through the center of the loose tube (101).
6. The central tube optical cable according to claim 1, wherein: There are multiple reinforcing members (104), and the multiple reinforcing members (104) are wound on the reinforcing yarn layer (102) along the same spiral direction to form an armor layer for protecting the loose tube (101).
7. The central tube optical cable according to claim 1, wherein: The outer surface of the reinforcement (104) is coated with an adhesive layer for bonding the outer sheath (103), and the adhesive layer is ethylene ethyl acrylate copolymer.
8. The central tube optical cable according to claim 1, wherein: The ratio of the cross-sectional area of the reinforcement (104) embedded in the outer sheath (103) at any cross-section to the total cross-sectional area of the reinforcement (104) is greater than or equal to 50%.
9. The central tube optical cable according to claim 1, wherein: The reinforcement (104) is a fiber reinforced plastic rod, the tensile strength of the reinforcement (104) is greater than or equal to 1100 MPa, and the tensile elastic modulus of the reinforcement (104) is greater than or equal to 50 GPa.
10. The central tube optical cable according to claim 1, wherein: A tear cord (107) for peeling off the outer sheath (103) is spirally wound between the outer sheath (103) and the reinforcing yarn layer (102).