Abstract: A fire-resistant cable (20) which is suitable for the transmission of high frequency signals in a local area network includes a core which comprises a plurality of twisted pairs (22,22) of insulated conductors (24,24) and a jacket (35). Each insulated conductor of each pair includes an elongated metallic member (26) and an insulation system (28). The insulation system which is characterized by a suitable low dissipation factor includes dual layers, an outer one of which includes a flame-retardant plastic material. Also, the insulation system is characterized by a suitably low dielectric constant and by compatibility with a relatively short pair twist scheme. In one embodiment, the insulation system includes an inner layer (30) of a polyolefin plastic material and an outer layer (32) of a flame-retardant polyolefin plastic material.

Abstract: A cable (20) includes a waterblocking member (29) which includes a superabsorbent polymer. The superabsorbent polymer includes an ionic constituent which is characterized in that its solubility product is substantially higher than that of carboxylate and in that it has a lower reaction rate for forming an anhydride than does carboxylate. The ionic constitutent may be selected from the group consisting of sulfate, sulfonate and phosphate and also includes a counter ion. Other constituents may include a carboxylate and a non-ionic group constituent. The superabsorbent polymer is such that the amount of crosslinking is sufficient to avoid the polymer going into solution, but is not so much as to affect adversely the water absorbency of the waterblocking member. Further, the superabsorbent polymer is much more salt tolerant and temperature tolerant than are prior art superabsorbent polymers.

Abstract: 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.

Abstract: An article (20) which is adapted to be positioned adjacent, for example, to the body of an animal or of a human being is a layered structure which includes a liquid pervious layer (22) and a liquid impervious layer (26). The article is applied to cause the liquid pervious layer to be contiguous with the body of the animal or of the human being. Interposed between the liquid pervious and impervious layers is an absorbent core (24). The absorbent core includes at least one absorbent member (35) which comprises a relatively porous substrate portion (37) which has been impregnated with a superabsorbent material. Waste liquid given off by the animal of the human being passes through the liquid pervious layer and into the absorbent core. This causes the absorbent core to swell, absorbing the liquid uniformly and preventing pass-through of further liquid toward the outside as well as preventing flow back of the liquid into contact with the body.

Abstract: A communications cable (20) includes water blocking provisions which are microbial resistant. The water blocking provisions include a microbial resistant water blocking member (35) comprising a laminate which includes two tapes (37--37) with a superabsorbent powder (40) therebetween. Advantageously, the superabsorbent powder on contact with moisture swells to block further intrusion of moisture and to prevent its movement longitudinally within the cable. The tapes of the laminate may be non-cellulosic such as for example a spunbonded polyester material which has suitable tensile strength and which has a relatively high porosity and further which prevents the growth of fungus. An adhesive system (42) included in the laminate is sufficient to hold together the tapes and the powder without inhibiting swelling of the powder on contact with water.

Abstract: An optical fiber splicing device (20) includes a glass cylindrically shaped capillary tube member (24) having a passageway formed therethrough eccentrically of the longitudinal axis of the capillary tube member. The capillary tube member is provided with a slot (86) such that a portion of the passageway in the form of a groove (88) extends across a planar surface (87) formed by the slot. The capillary tube member is mounted in a housing (22) which is made of a material and formed to provide a lens opposite to the slot to facilitate visual inspection of ends of end portions of two optical fibers which are positioned in the groove. A spring clamp (26) is mounted to the housing in a first position spaced from the planar surface to allow insertion of fiber end portions into the groove.

Abstract: In order to provide a substrate such as an optical preform rod (24) which is suitable for insertion into a tube and which has a transverse cross section that is substantially circular and disposed concentrically about a longitudinal axis of the substrate substantially along its entire length, a force-applying means such as a graphite roller (52) is adapted to be moved incrementally toward an axis of rotation (35) about which the preform rod is turned rototably. Movement is discontinued when there is an indication that the force-applying means has been in continuous engagement with the preform rod for at least a predetermined portion of the periphery of the rod. In a preferred embodiment, the engagement of the force-applying means and the preform rod is discontinued after a predetermined time, whereafter the force-applying means again is moved toward the axis of rotation.

Abstract: A totally dielectric cable includes a core (21) comprising a plurality of optical fiber transmission media (24--24). The core is enclosed by a core tube (34) which is made of a plastic material and water blocking provisions are provided within the core tube for preventing the longitudinal migration of water. A water blocking tape (44) may be provided in engagement with an outer surface of the core tube and a plastic jacket is extruded thereover. Interposed between the outer surface of the jacket and the core tube are two diametrically opposed pluralities (60--60) of strength members each of which may be made of glass fibers. At least one strength member (62) of each plurality is rod-like to provide compressive as well as tensile strength for the cable. The remaining strength members of each plurality are relatively flexible rovings (64--64) which supplement the tensile strength of the rod-like members.

Abstract: Methods are provided for making an optical fiber transmission medium which includes optical fiber (21) provided with a coating system (31) typically including two layers each of a different coating material. An inner layer (32) of a first coating material is called the primary coating and an outer layer is termed the secondary. In order to achieve desired performance characteristics, performance is related to properties of a coating system. The coating materials have well defined moduli and the second coating material has an elongation which is substantially less than in prior secondary coating materials. Adhesion levels which are optimized rather than maximized are substantially stable with respect to time. Curing of the coating materials may be accomplished simultaneously or in tandem with the application separately of the coating materials.

Abstract: A preform tube (31) is caused to be collapsed into a preform rod by causing a heat zone (54) provided by a torch assembly (50) to traverse the tube longitudinally in a plurality of passes. During this collapse mode, a muffle tube (100) encloses that portion of the tube which extends through the torch assembly. The muffle tube projects a predetermined distance beyond one major face of the torch assembly. The torch assembly comprises annular semi-circular end plates and an annular semi-circular center portion having a plurality of exit ports through which gases are directed into engagement with the tube. The center portion is caused to be recessed between the end plates thereby causing the heat zone generated by the gases to be narrowed. The narrowing of the heat zone and the substantial confinement of the heat energy within the muffle tube cooperate with increased gas flow rates to cause the tube to be collapsed in a time period which is substantially less than that achieved by prior art methods.

Abstract: A group of loose cabled optical fibers (32--32) destined to be terminated by a multi-fiber connector device is first fabricated into an optical fiber ribbon (30). The optical fibers of the group are threaded through portions of an organizing shuttle (20) and brought into planar juxtaposition with each other by the cooperation of a curved surface (112) and a burnishing bar assembly (98). As the organizing shuttle is caused to be moved along a track (42), the burnishing bar assembly causes the planar array of fibers to be embedded into an adhesive coating of a first binding tape (34) which is secured along the length of the track. In a preferred embodiment, a second tape (35) is applied over the fibers and the first tape. The ribbon is trimmed of excess longitudinal side portions of the binding tapes to provide a ribbon of desired width.

Abstract: A tunable fiber Farby-Perot interferometer includes two aligned ferrule assemblies (22--22) having adjacent end faces separated by a gap. Each assembly includes a mirror (40) disposed transverse to a longitudinal axis (28) of the assembly and embedded internally therein adjacent to the exposed end surfaces which defines the gap. Each ferrule assembly is held in a sleeve (74) disposed in an end fixture (70) with a piezoelectric transducer system (44) extending between end fixtures. Means (82--82) are provided in each end fixture for deforming slightly the sleeve to cause the ferrule assembly disposed therein to be moved into alignment with the other. The transducer system is operated to adjust the length of the gap between the exposed adjacent end faces. Also, the facilities including the transducer system are provided such that a portion or portions of it may be operated selectively to fine tune further the alignment between the fibers.

Abstract: An apparatus (20) is provided for transferring articles (40--40) from a pickup position to a pickoff position and then to a dropoff position. The apparatus includes a pair of pickup arms (60--60) which are spaced apart to engage lugs (42--42) oppositely extending from an article to be transferred. As the transfer arms are caused to be moved rotatably, the article is transferred to the pickoff position whereat the lugs are adjacent to stepped end portions (88--88) of a pair of pickoff arms (80--80). Further movement of the transfer arms causes the article to engage surfaces (92--92) of the stepped free ends of the pickoff arms and to be supported by engagement of the lugs with surfaces (94--94) of the stepped end portions of the pickoff arms. Afterwards, the pickoff arms are turned to allow the article to descend until, at a predetermined position, the lugs of the article become engaged with a conveyor (100) and become disengaged from the pickoff arms.

Abstract: An optical fiber package (20) is provided by winding a plurality of convolutions in a plurality of layers on a bobbin. To each layer is applied an adhesive material (45) which in a preferred embodiment is a mixture comprising a reactive silicone copolymer resin, a solvent system which includes an aromatic constituent, a catalyst and a wetting agent. The mixture has a modulus behavior which is relatively stable with respect to time throughout a relatively wide operating temperature. Inasmuch as the solvent system and the method of application of the mixture are effective to control the rate of precipitation and the rate of cure of the silicone constituent, the surface roughness of the convolutions is controlled. After the desired number of convolutions have been wound, the package is subjected to a heat treatment which relieves stresses in the wound fiber and which completes the cure of the adhesive material.

Abstract: A low loss, tunable optical filter (20) comprises two ferrules (24--24) which are aligned axially with each of two adjacent end faces being provided with a wafer (30). A mirror (40) is embedded between each end face and its associated wafer, the wafer being bonded to the end face of its associated wafer. Optical fiber is disposed in a passageway which extends through each ferrule and through the associated wafer. The ferrules and associated wafers are supported to cause adjacent exposed faces of the wafers to be in predetermined spatial relation to each other. Any gap therebetween may be fixed or may be adjusted by a piezoelectric transducer system (44). The disclosed filter provides rejection ratios which are sufficiently high for frequency discrimination in frequency shift keying systems and for channel selection or switching in wave division multiplexer applications.

Abstract: Containers (20--20) which held UV curable acrylate materials commonly used as coating materials for drawn optical fiber are treated prior to disposal. Because of the presence of acrylate residues therewithin, the container cannot be disposed of in a landfill and has been incinerated. This problem has been overcome by exposing the residue within the container to suitable reproducible radiation determined in accordance with the photochemistry of the residue materials to cure completely the remaining acrylate material and thereby reduce its reactivity.

Abstract: An optical fiber cable (20) which is suitable for service from a distribution closure to a customer's premises includes a transmission media core (21) enclosed in a relatively rigid tubular member (40). The relatively rigid tubular member is enclosed in a jacket (44) comprising a plastic material which has a cut-through resistance which is substantially less than that of the tubular member. Interposed between the tubular member and an outer surface of the jacket is a strength member system comprising two yarn-like longitudinally extending strength member groups (52--52). The strength member grops are diametrically opposed to each other and are disposed in engagement with the tubular member.

Abstract: A bonded sheath cable (20) includes a core (22) and a longitudinally wrapped outer shield (36) which encloses the core. An outer surface of the shield is provided with a layer (39) of a copolymer adhesive material which causes the shield to bond to an outerlying plastic jacket (41). The shield is wrapped longitudinally about the core to have overlapping portions (51,53) which form a longitudinal seam (38). In order to avoid seam splitting of the jacket along a line aligned with the longitudinal edge (55) of the outer overlapping portion, control means (60) comprising a polymeric material is provided to extend in bicircumferential directions from the longitudinal edge thereby reducing the bond along the overlap seam and allowing the cable to bend and/or twist without causing a stress concentration in the plastic overlying the longitudinal edge.

Abstract: A hybrid optical fiber, copper conductor transmission media cable (20) which is suitable for use in local area network application includes a core (22) comprising two arrays (25,40) of longitudinally extending portions. One array (25) includes optical fibers disposed between two strength members (27--27) whereas the other array comprises metallic conductors (42--42). Each array includes a matrix material (30,45) in which the longitudinally extending portions are enclosed with adjacent portions being connected by a web (32,47). The two arrays are enclosed by a jacket (50) which has an oval shaped configuration. The configuration of component portions of the cable as well as the materials thereof are determined to cause the neutral axis of bending to be in a desired location which minimizes losses in the transmission media.

Abstract: An optical fiber package (20) is provided by winding a plurality of convolutions in a plurality of layers on a bobbin. To each layer is applied an adhesive material (45) which in a preferred embodiment is a mixture comprising a relative silicone copolymer resin, a solvent system which includes an aromatic constituent, a catalyst and a wetting agent. The mixture has a modulus behavior which is relatively stable with respect to time throughout a relatively wide operating temperature. Inasmuch as the solvent system and the method of application of the mixture are effective to control the rate of precipitation and the rate of cure of the silicone constituent, the surface roughness of the convolutions is controlled. After the desired number of convolutions have been wound, the package is subjected to a heat treatment which relieves stresses in the wound fiber and which completes the cure of the adhesive material.