摘要:
A cable (20) which may be used in an aerial or buried installation to serve customers' premises and which is a composite optical fiber-copper conductor type serves present customer needs but has the capability to fulfill the service requirements predicted in the communications market of tomorrow. The cable includes one or more reinforced optical fiber units (22--22) and one or more metallic conductor pairs enclosed in a sheath system. Each optical fiber unit is reinforced to include a plurality of strength members (40--40) arrayed about a buffered optical fiber (36) to enclose the optical fiber and to provide columnar strength to resist compressive forces. A filling compound (52) is disposed within the unit between a jacket (50) which encloses the strength members and the buffered optical fiber.
摘要:
An asymmetrically shaped signal polarization maintaining optical waveguide including an asymmetrically shaped optical fiber surrounded by glass cladding, hard polymer coating, soft porous polymer buffering layer, porous polymer laminate inner layer, polyester laminate outer layer bearing tabs oriented to an axis of asymmetry of the optical fiber, braid fiber sheath, and outer jacket, the observable tab orientation on the outside of the cable providing location means of the axis of asymmetry of the optical fiber.
摘要:
An optical fiber cable (20) includes a core (21) comprising at least one optical fiber (24) which is enclosed in a tubular member (34) and which includes a sheath system (40). The sheath system includes two strength members 42--42 which extend linearly longitudinally along the cable parallel to a longitudinal axis (29) of the cable. The strength members are enclosed in a plastic jacket (46). The strength members have predetermined relative tensile and compressive stiffnesses. The stiffnesses are such that the strength members are capable of withstanding expected compressive as well as tensile loading and are coupled sufficiently to the jacket to provide a composite arrangement which is effective to inhibit contraction and which controls the position of the neutral axis during bending while providing suitable flexibility. The strength members in a preferred embodiment are made of a metallic material such as steel and have tensile and compressive stiffness which are substantially equal to cause the plane of bending to extend through the strength members. In other embodiments, the core is filled with a waterblocking material, the tubular member is enclosed by a water absorbent tape and/or a metallic shield and metallic conductors may extend colinearly with the strength members.
摘要:
An optical fiber band comprising an optical fiber intermediate and equi-distant from a pair of metal wires, each having substantially the same temperature coefficient of expansion as the optical fiber, embedded in a synthetic thermoplastic material and cables formed therewith. In one embodiment of a cable, a plurality of bands are bunched together and surrounded by a thermoplastic sheath. In another embodiment, a plurality of bands are disposed in side-by-side relation and preferably, secured together and a plurality of such bands are wound helically in successive layers around a supporting core, such as wire rope, and are covered by a thermoplastic sheath. Also, processes for forming the bands by extruding the thermoplastic over the fiber and wires or by sealing the fiber and wires between a pair of thermoplastic films.
摘要:
A drop cable includes a jacket, first and second support members, and at least one optical fiber. The jacket has a oval-shaped cavity defined therein, where the minor dimension of the cavity is as small as about 0.25 mm and wherein the major dimension of the cavity is in a range of 0.25 mm to 10 mm. The first and second support members are arranged on opposing sides of the cavity and run generally longitudinally. The optical fiber is within the cavity and has a length greater than a length of the drop cable. Further, the optical fiber is in a substantially serpentine configuration in the cavity, where the serpentine configuration is substantially along a plane defined by a major axis of the oval-shape of the cavity.
摘要:
A method of forming a low-cost drop cable (10) is disclosed. The method includes providing a protective cover material (352) having an extrusion temperature of 140° C.≦TE≦160° C. The protective cover material is extruded through a die (420) having a single aperture (424) that defines the cable's elongate cross-sectional shape. The extrusion process involves covering first and second strength members (30) on either side of at least one optical fiber (50). The combination of the low temperature of the extrudable protective cover material and the elongate shape of the single die aperture cause the formation of an oval cavity (20) within the extruded protective cover material. The oval cavity has major and central axes (A1, AC) and surrounds the at least one optical fiber. The strength members lie along the cavity major axis. Tensioning the strength members during extrusion and then releasing the tension causes the drop cable length to be reduced. This gives rise to an excess fiber length, which adopts a serpentine configuration substantially in a plane (PF) defined by the major and central axes (A1, A2) of the oval cavity.
摘要:
Composite cables operative to transmit information in electrical and/or optical transmission modes. The cables can include an electrical coaxial conductor comprising a generally central electrical conductor in a dielectric matrix. At least one optical transmission component is integrated with the matrix. The matrix can include at least two optical transmission components disposed on generally opposed sides of the central electrical conductor. Any optical transmission component can be substantially mechanically de-coupled from the matrix. In addition, the matrix can include at least one ripcord, and an indicia can be formed on the matrix for locating the position of an optical transmission component. The composite cables can include structural features for imparting a preferential bend to the cable.
摘要:
An optical fiber cable including a cable jacket having a longitudinally extending inner cavity with a non-circular cross section, and at least two longitudinally extending strength members, wherein the non-circular cross section is disposed so that a minor axis thereof is substantially aligned with a line joining the at least two longitudinally extending strength members.
摘要:
An unshielded buried service wire (20) includes a core (22) and a jacket (40). The core comprises two pairs (24-24) of insulated metallic conductors (26-26). Also associated with each conductor pair is a longitudinally extending waterblocking member (33) which inhibits the flow of water longitudinally of the wire. The jacket has a transverse cross sectional configuration which is generally oval. Adjacent to each of opposed small radius of curvature portions of the service wire and embedded substantially in the jacket is a longitudinally extending, rod-like strength member (50) which is caused to adhere to plastic material of the jacket.
摘要:
An aerial service wire (20) includes a jacket (40) having a generally rectangularly shaped cross section and comprising a polyvinyl chloride plastic material. Enclosed by the jacket are two groups of strength members (36--36) each of which includes a plurality of filaments and each of which is impregnated with a material which is compatible with that of the jacket. The strength members are disposed along axes (52,54) of the cross section which are normal to an axis (42) which passes through a geometric center through which a longitudinal axis (50) of the jacket passes. Conductors (30--30) which are individually insulated are disposed adjacent to the longitudinal axis with each strength member being disposed between the conductors and the outer surface of the jacket.