Abstract: A cable that protects an object includes: a sheath; and a cylindrical reinforcement member disposed inside the sheath and that surrounds the object. The cylindrical reinforcement member has a first side edge and a second side edge that extend in a longitudinal direction. The cylindrical reinforcement member is formed of a cable reinforcement sheet including: a first metal sheet; and a second metal sheet joined to the first metal sheet. A portion of the first metal sheet overlaps a portion of the second metal sheet, and the overlapping portions define a joint portion where the first metal sheet and the second metal sheet are joined. The joint portion is inclined, from the second side edge to the first side edge, toward the first metal sheet.

Abstract: An optical cable wiring method, includes: installing a bundle of optical cables from a utility pole as a starting point of a first wiring path to a branch point on the first wiring path; dividing, at the branch point, the bundle of optical cables into a first group and a second group; installing one of the optical cables in the first group along the first wiring path ahead of the branch point; and installing one of the optical cables in the second group along a second wiring path branching from the first wiring path.

Abstract: A method of exposing a core of an optical fiber cable that includes: a core including an optical fiber; a wrapping tube wrapping the core; a jacket housing the core and the wrapping tube; and a tension-resisting member of a Fiber Reinforced Plastic (FRP) embedded in the jacket, includes: making a cut in a circumferential direction in the jacket at a position closer to a first end portion of the optical fiber cable than to a second end portion of the optical fiber cable in a longitudinal direction; bending the optical fiber cable at a portion having the cut and fracturing the tension-resisting member; and removing a removal portion of the jacket that is disposed between the cut and the first end portion.

Abstract: An optical fiber cable production method includes: feeding a core including optical fibers; winding a reinforcing wrap around the core and forming an overlapping portion in which end portions of the reinforcing wrap overlap each other at a portion of the reinforcing wrap in a circumferential direction; and performing extrusion molding of a sheath on an outside of the reinforcing wrap. The overlapping portion extends in a longitudinal direction of the optical fibers. In the performing extrusion molding, a resin that forms the sheath is inserted into a portion of the overlapping portion.

Abstract: An optical fiber arrangement method includes: preparing an intermittently connected optical fiber ribbon including optical fibers arranged side by side at a first pitch larger than a fiber diameter; holding a non-connecting region of the optical fiber ribbon with a holder, where connecting portions intermittently connect the optical fibers extending out from the holder to each other; changing a width of the optical fiber ribbon in an interior of the holder; and arranging the optical fibers, extending out from the holder, with intervals of the optical fibers changed from the first pitch to a second pitch smaller than the first pitch by removing the connecting portions in a state where the holder is holding the optical fibers.

Abstract: [Problem] When a surface of the optical fiber ribbon is rough, the microbending loss is increased due to the irregularities formed on the surface of the optical fiber ribbon. [Solution] An intermittently connected optical fiber ribbon of the present disclosure, includes: a plurality of optical fibers arranged in a predetermined direction; and connecting portions that intermittently connect two adjacent ones of the optical fibers. A peripheral cover portion formed of resin configuring the connecting portions is formed on a periphery of the optical fibers. An arithmetic mean roughness Ra of a surface of the peripheral cover portion is 0.41 ?m or lower.

Abstract: Provided is an optical fiber ribbon capable of achieving higher density and reduction in diameter and accurately placing optical fibers in V-shape grooves in a fusion machine without failure. The optical fiber ribbon 1 includes three or more of optical fibers 2 arranged in parallel and connecting portions 3 connecting adjacent two optical fibers 2 together, the connecting portions 3 being intermittently provided in each of a ribbon longitudinal direction and a ribbon width direction. The connecting portions 3 are each formed in such a manner as to fill resin into a gap S formed between adjacent two optical fibers 2, and both surfaces of the respective connecting portions 3 are each formed into a recess having a concave shape curved toward a center of the gap S to separate from lines 4,5 each connecting contact points of the optical fibers 2 when being placed on a horizontal surface.

Abstract: An elongated-object drum includes: a drum on which an elongated object is wound; and a management module that is attached to the drum and comprises: an acceleration sensor that detects acceleration of the drum, a computation device that performs computation based on a detection result from the acceleration sensor, and a storage device that stores a computation result obtained by the computation device based on the detection result from the acceleration sensor.

Abstract: An intermittently connected optical fiber ribbon includes optical fibers, disposed side by side in a width direction of the optical fibers, and connecting portions that each intermittently connect two adjacent ones of the optical fibers. A center-to-center distance between any of the two adjacent ones of the optical fibers is greater than a diameter of the individual optical fibers. A total volume shrinkage per meter per 1° C. of the connecting portions of a single one of the optical fibers is 0.00070 mm3/m·° C. or lower.

Abstract: Provided is an optical fiber ribbon capable of achieving higher density and reduction in diameter and accurately placing optical fibers in V-shape grooves in a fusion machine without failure. The optical fiber ribbon 1 includes three or more of optical fibers 2 arranged in parallel and connecting portions 3 connecting adjacent two optical fibers 2 together, the connecting portions 3 being intermittently provided in each of a ribbon longitudinal direction and a ribbon width direction. The connecting portions 3 are each formed in such a manner as to fill resin into a gap S formed between adjacent two optical fibers 2, and both surfaces of the respective connecting portions 3 are each formed into a recess having a concave shape curved toward a center of the gap S to separate from lines 4,5 each connecting contact points of the optical fibers 2 when being placed on a horizontal surface.

Abstract: An optical fiber cable includes: a sheath; a core that is housed in the sheath and comprises optical fibers; tensile strength members embedded in the sheath; and ripcords embedded in the sheath. Recesses and protrusions are disposed alternately in a circumferential direction on an outer circumferential surface of the sheath. The recesses each include: two connecting portions respectively connected to radial inner ends of two adjacent protrusions; and a bottom surface positioned between the two connecting portions. In a transverse cross-sectional view, the ripcords are positioned inside some of the protrusions, and the tensile strength members are positioned inside the remaining protrusions.

Abstract: An optical fiber cable includes: a sheath; and a core that is housed in the sheath and includes an intermittently-adhered optical fiber ribbon including optical fibers and adhesive portions for intermittently adhering the optical fibers in a longitudinal direction. Recesses and protrusions are disposed alternately in a circumferential direction on an outer circumferential surface of the sheath. The recesses each include: two connecting portions respectively connected to radial inner ends of two adjacent protrusions; and a bottom surface positioned between the two connecting portions.

Abstract: An optical fiber cable includes a core that includes an assembled plurality of optical fibers; an inner sheath that accommodates the core therein, a pair of tension members that are embedded in the inner sheath and that are disposed on opposite sides of the core, and an outer sheath that covers the inner sheath. The inner sheath is formed with a dividing portion that divides an inner peripheral surface and an outer peripheral surface of the inner sheath in a circumferential direction. The dividing portion extends along a longitudinal direction in which the optical fiber cable extends.

Abstract: A method for manufacturing an optical fiber ribbon includes: forming a colored layer on to each of a plurality of optical fibers and forming an optical fiber ribbon by curing a connecting material applied to a surface of the colored layer of each of the optical fibers to form connection parts that connect adjacent ones of the optical fibers. Forming the colored layer further includes: applying a coloring agent to the optical fibers and curing the coloring agent such that uncured resin remains on the surface of the colored layer. Forming the optical fiber ribbon further includes: applying the connecting material to the surface with the uncured resin and curing the connecting material and the uncured resin on the surface of the colored layer.

Abstract: An optical fiber unit includes: a first optical fiber ribbon that intermittently connects a first plurality of optical fibers; a second optical fiber ribbon that intermittently connects a second plurality of optical fibers; and interlayer connection parts that intermittently connect the first optical fiber ribbon and the second optical fiber ribbon in a length direction while the first optical fiber ribbon and the second optical fiber ribbon are layered and arranged. The first optical fiber ribbon and the second optical fiber ribbon are layered and arranged such that optical fibers having a same fiber number of the first optical fiber ribbon and the second optical fiber ribbon are aligned in a up-down direction perpendicular to the length direction.

Abstract: An optical fiber cable including an optical fiber ribbon in a pipe, wherein the ribbon includes at least two optical fibers arranged side by side, and wherein at least two of the optical fibers are bonded intermittently along a length of the fibers.

Abstract: An intermittent connection-type optical fiber ribbon including: optical fibers aligned in a width direction of the intermittent connection-type optical fiber ribbon; and a connection part disposed between two separation spaces that are aligned in a lengthwise direction of the intermittent connection-type optical fiber ribbon and that separate adjacent ones of the optical fibers. A percentage content of the air bubbles is equal to or less than 15.5%. The percentage content of the air bubbles is a proportion of a total area of the air bubbles contained in the connection part to an area of the connection part in a section acquired by cutting the intermittent connection-type optical fiber in the width direction.

Abstract: An optical fiber cable includes: a cable body having a core and an inner sheath that accommodates the core; a reinforcing sheet that surrounds the cable body; an outer sheath that accommodates the cable body and the reinforcing sheet; and an outer ripcord that is embedded in the inner sheath. The inner sheath includes a projection that projects outwardly in a radial direction of the optical fiber cable. At least part of the outer ripcord is disposed inside the projection.

Abstract: An optical fiber cable manufacturing method using a manufacturing apparatus including an SZ twisting device, an extrusion molding device, and a pressing portion disposed between the SZ twisting device and the extrusion molding device is provided. The method including: twisting optical fibers or optical fiber units in an SZ manner using the SZ twisting device to form an optical fiber bundle; and covering the optical fiber bundle with a sheath using the extrusion molding device while pressing the optical fiber bundle using the pressing portion.

Abstract: An optical fiber cable includes: a sheath including recesses and protrusions that are alternately disposed in a circumferential direction on an outer circumferential surface of the sheath; a core that includes optical fibers and is accommodated in the sheath; and tensile strength members embedded in the sheath. The core is interposed between the tensile strength members in a transverse cross-sectional view. In the transverse cross-sectional view, the tensile strength members are embedded in portions of the sheath facing outward from the core in a first direction in which the two tensile strength members face each other in the transverse cross-sectional view.