JP-7856099-B2 - Fiber optic cable

JP7856099B2JP 7856099 B2JP7856099 B2JP 7856099B2JP-7856099-B2

Inventors

佐藤文昭
大貫聡
大塚健一郎

Assignees

住友電気工業株式会社

Dates

Publication Date: 20260511
Application Date: 20220331
Priority Date: 20210524

Claims (6)

A cable body comprising 3000 or more optical fiber cores and an outer sheath material for housing the optical fiber cores, A multi-core connector connected to the end of the optical fiber core, The cable has a flexible tube provided at at least one end of the cable body, The multi-core connector is housed in the flexible tube. The outer diameter of the flexible tube and the outer diameter of the cable body are 60 mm or less. The allowable bending radius of the aforementioned flexible pipe is 220 mm. The aforementioned outer covering material contains silicone in a mass percentage of 0.2% or more and 1.5% or less. An optical fiber cable having a bending stiffness of 25 N·mm² or less, and the amount of variation in the bending stiffness in the circumferential direction of the optical fiber cable being within 5% of the average value of the bending stiffness .
The optical fiber cable according to claim 1, wherein the static friction coefficient between the outer sheath material and the stainless steel plate is 0.20 or more and 0.46 or less.
The optical fiber cable according to claim 1 or claim 2, wherein the cross-section of the outer sheath is polygonal.
The optical fiber cable according to any one of claims 1 to 3, wherein the optical fiber cores are arranged in parallel, and in some or all of the optical fiber cores, connecting portions where adjacent optical fiber cores are connected and unconnected portions where adjacent optical fiber cores are not connected are intermittently provided in the longitudinal direction, thereby forming an intermittently connected optical fiber ribbon.
The device further includes a pitch conversion unit provided between the first end of the optical fiber ribbon and the multi-core connector for converting the pitch of the optical fiber cores, The pitch of the optical fiber cores in the multi-core connector is longer than the pitch of the optical fiber cores in the optical fiber ribbon. The outer diameter of the optical fiber core is 160 μm or more and 185 μm or less. The optical fiber cable according to claim 4 , wherein the core density of the cable body is 10 cores/ mm² or more.
The optical fiber cable according to any one of claims 1 to 5 , wherein the glass diameter of the optical fiber core is 80 μm or more and 120 μm or less.

Description

This disclosure relates to optical fiber cables. This application claims priority under Japanese application No. 2021-086748, filed on 24 May 2021, and incorporates all the provisions contained in the said Japanese application. Patent Document 1 discloses a multi-core optical fiber cable in which multiple optical fiber ribbon cores are densely bundled and integrated. Japanese Patent Application Publication No. 2004-161499 An optical fiber cable relating to one aspect of this disclosure is A cable body comprising 3000 or more optical fiber cores and an outer sheath material for housing the optical fiber cores, A multi-core connector connected to the end of the optical fiber core, The cable has a flexible tube provided at at least one end of the cable body, The multi-core connector is housed in the flexible tube. The outer diameter of the flexible tube and the outer diameter of the cable body are 60 mm or less. The allowable bending radius of the aforementioned flexible pipe is 220 mm. The aforementioned outer covering material contains silicone in a mass percentage of 0.2% or more and 1.5% or less. The bending stiffness of the optical fiber cable is 25 N·mm² or less, and the variation in bending stiffness in the circumferential direction of the optical fiber cable is within 5% of the average value of the bending stiffness. Figure 1 is a diagram illustrating an optical fiber cable according to one aspect of this embodiment.Figure 2 is a cross-sectional view taken along the line A-A in Figure 1.Figure 3 is a plan view showing an intermittently connected optical fiber ribbon in the longitudinal direction.Figure 4 illustrates how an optical fiber cable according to one aspect of this embodiment is laid.Figure 5 illustrates an example of a device used to calculate the static friction coefficient of an optical fiber cable according to one aspect of this embodiment.Figure 6 shows the tensile tension as a function of the towing length.Figure 7 is a cross-sectional view of another optical fiber cable according to one aspect of this embodiment. [Issues this disclosure aims to address] In outdoor wiring, fiber optic cables are often fusion-spliced within junction boxes such as closures during the wiring process, and are also fusion-spliced or connected via connectors at the point of entry into the central office. Therefore, for example, with ultra-high-density fiber optic cables (3000 cores or more), fusion splicing can take a considerable amount of time. Furthermore, when ultra-high-density fiber optic cables are laid in ducts using a traction method, a high occupancy rate of the fiber optic cable within the duct can increase tensile strength, potentially reducing ease of cable installation. For these reasons, there is a need for fiber optic cables that can improve work efficiency during installation. This disclosure aims to provide an optical fiber cable that can improve work efficiency during the installation of optical fiber cables. [Description of Embodiments in this Disclosure] First, the embodiments of this disclosure will be listed and described. An optical fiber cable relating to one aspect of this disclosure is (1) A cable body including 3,000 or more optical fiber cores and an outer sheath material that houses the optical fiber cores, A multi-core connector connected to the end of the optical fiber core, The cable has a flexible tube provided at at least one end of the cable body, The multi-core connector is housed in the flexible tube. The outer diameter of the flexible tube and the outer diameter of the cable body are 60 mm or less. The allowable bending radius of the aforementioned flexible pipe is 220 mm. The aforementioned outer covering material contains silicone in a mass percentage of 0.2% or more and 1.5% or less. The bending stiffness of the optical fiber cable is 25 N·mm² or less, and the variation in bending stiffness in the circumferential direction of the optical fiber cable is within 5% of the average value of the bending stiffness. With this configuration, since multi-core connectors are provided at the ends of the optical fiber cores, the time required for fusion splicing can be shortened or eliminated. Furthermore, the outer sheath of the optical fiber cable according to the above configuration contains silicone at a mass percentage of 0.2% to 1.5%. Therefore, when the optical fiber cable is laid in a duct using a traction method, the coefficient of friction between the optical fiber cable and the duct can be reduced. Consequently, the optical fiber cable according to the above configuration has good cable routing properties. In this way, the above configuration can improve the work efficiency when laying optical fiber cables. With this configuration, the multi-core connector is housed in a flexible tube, so the multi-core connector is not exposed, preventing damage or breakage of the connector during traction. This configuration allows for a smaller outer diameter for the flexible tube and