Abstract: Methods and a system of this invention are used to determine whether a fault in a subscriber loop is located between a telephone central office and a reference point or between the reference point and subscriber terminal equipment without opening the loop. Included in the system are two current interrupter networks one of which is connected in series with the tip conductor and one in series with the ring conductor. If a fault exists between the central office and the reference point, the application of a test signal causes a constant current reading on a meter at a test center. On the other hand, if a fault is present in the loop beyond the reference point, an oscillatory current reading appears on the meter. The system also includes a recognizable impedance termination network which is connected between the tip and ring conductors of the subscriber loop to facilitate testing for opens in the tip and ring conductors.

Abstract: A cable which is suitable for use as a riser cable in buildings comprises a plurality of conductors each of which is covered with a composite insulation. The composite insulation comprises an inner layer of an expanded polyethylene material and an outer layer of a polyvinyl chloride material with the percent expansion of the inner layer and the thickness of the outer layer being such as to optimize several cable parameters. The resultant cable is one which has excellent fire-retardant properties such as, for example, an unusually low fuel content. Advantageously, this same cable lends itself to color coding for inside wiring and is capable of having a relatively high pair count density. All these parameters are optimized within the framework of specific transmission requirements.

Abstract: The invention relates to the formation of a substantially circular metallic shield (37) about a cable core (32) by wrapping a metallic tape (64) longitudinally about the core with longitudinal edge portions of the tape being overlapped by a forming key (100) to provide a closed seam (38). As the seam is formed, an underlying longitudinal edge portion (48) of the shield is supported while an overlying longitudinal edge portion (45) at the overlap is directed inwardly toward the cable core to preclude its protrusion into a jacket (39) which is subsequently extruded over the shielded cable core. A relatively thin strip (145) of metal attached to an inner surface of the forming key assures formation of the seam before juxtaposing the longitudinal edge portions and the core, and avoids penetration of a priorly formed inner shield by the longitudinal edge of the outer shield to prevent rotation of the inner shield and undesirable alignment of the shield seams.

Abstract: An escapement apparatus of this invention accepts a contiguously arrayed plurality of conductors and dispenses them into a carrier spaced apart on centers to facilitate their assembly to a ribbon connector. The escapement apparatus includes a guideway having a first portion which receives the conductor array and which is inclined at an angle to the horizontal. The array is received in the first portion of the guideway and a second, more steeply inclined portion and is biased toward an exit. The exit communicates with a passageway along which is moved a toothed carrier. The carrier includes a plurality of nests having a spacing which corresponds to that of the connector. As the carrier is moved at a velocity which is controlled relative to forces applied to the conductor array in the guideway, the nests are aligned seriatim with the exit to facilitate the movement of a conductor into each nest.

Abstract: Methods and apparatus of this invention are used to maintain a predetermined arrangement of stranded multi-conductor pair cable units (23--23) within a first group (24) of units while controlling the formation of a laminate (30) comprising a plastic-coated metallic strip (31) into an internal shield which is disposed between the first group and a second group (26) of the units. A device (100) is interposed between faceplates (71, 82) through which the units and the strip are advanced prior to their advance through closing dies (131, 132) and apparatus which encloses the core with a sheathing system. The device controls the formation of the internal shield from the strip and is effective to prevent any buckling of the strip as it is formed into a configuration having arcuate end portions that partially enclose the groups of the units.

Abstract: A system (20) for providing clean air to an apparatus (24) for drawing lightguide fiber (21) from a preform (22) includes a plenum (52) and ducts through which room air is pulled and filtered. The filtered air is flowed into each of a plurality of stacked enclosures (66, 67, and 68) each of which surrounds partially the drawing apparatus and portions of the preform and/or fiber. Also, the filtered air is directed transversely past the fiber and preform at a velocity which is sufficiently low to avoid undue flutter of the fiber. Filters are arranged in ascending magnitude of efficiency proceeding from an intake (41) for the room air to the vicinity of the preform and fiber. A delivery system which is associated with each drawing apparatus is considerably less expensive than a clean room and allows maintenance of any one system or its associated drawing apparatus without discontinuing the drawing operation of other systems in the same room.

Abstract: A conical end portion of a connector plug and an end portion of a lightguide fiber which is encapsulated by the plug are prepared to form a conical end portion which is suitable for interconnection with a conical end portion of another plug within a sleeve with precise end separation of opposing end portions of the fibers. The conical portion of the plug is seated in engagement with a surface which is mateable with the outwardly facing surface of a conical end portion of the plug with an end portion of the fiber extending beyond the plug. In order to prepare the lightguide fiber, a disc which is mounted for rotation about an axis that is parallel to the longitudinal axis of the end portion of the lightguide fiber is moved along a path of travel obliquely transverse of the lightguide fiber. This disc is rotated to cause its peripheral edge surface to sever the portion of the lightguide fiber that extends from the plug to form an end surface.

Abstract: A tool for assembling a plurality of conductors into secured engagement with a mandrel of a multicontact electrical connector includes a plurality of spaced combs which are positioned adjacent a nest to hold the conductors transversely above a mandrel which is supported in the nest. In each cycle of operation, a head of the tool is prepositioned with respect to the nest and moved into engagement with the conductors to cause a forming die of the head to partially form the conductors about the mandrel and cooperate with a blade adjacent the nest to sever excess lengths of free end portions of the conductors. The head is repositioned with respect to the next so that when the head is again moved, in a second step of the cycle, forces are applied which are sufficient to form the conductors completely about the mandrel with each conductor being pressed into secured engagement with an associated recess on each side of the mandrel.

Abstract: Apparatus for heating a vertically suspended preform from which lightguide fiber is drawn includes a torch having a plurality of ducts that open to a surface adjacent to a lower end of the preform. Fuel and oxidizing gases flow from the ducts, mix at the surface and flame about a necked-down, lower portion of the preform to form a melt cone from which the fiber is drawn. The ducts and the preform are positioned to cause a combustion zone of each flame to impinge upon the preform. In a preferred embodiment, the openings of the ducts are arrayed in a circle which is referred to as a pitch circle and which has a diameter that is less than that of the preform. Also, the ducts are arranged so that the gases are directed at a predetermined angle to the axis of the preform.

Abstract: In terminating a ribbon which comprises an array of lightguide fibers, a substrate having a plurality of parallel grooves is positioned in a nest and supported at its end portions after which an end portion of the ribbon is moved longitudinally to cause the fibers to be separated by a comb-like device adjacent one end of the nest after which the ribbon is secured with a clamp adjacent the other end of the nest. Another substrate having aligned grooves is placed over the fibers so that the fibers are held in channels formed by the opposing grooves after which the assembly of substrates and fibers are secured together with a temporary clamp which applies compressive forces to end portions of the assembly along a longitudinal centerline of the assembly. Then a vise which includes jaws having parallel surfaces for engaging the substrate is moved toward the assembly to position a lower jaw under the lower substrate and an upper jaw above the upper substrate.

Abstract: A telephone cord includes a length of cordage having each end terminated with a modular plug with the plug at one end disposed within a specially designed, easily identifiable cavity of a unipartite housing of a coupler jack of this invention. The coupler jack also includes a conventional plug-receiving cavity and a plurality of wire-like contact elements having retroflexed end portions which are positioned in the cavities to engage terminals of inserted plugs. The plug that is disposed within the specially designed cavity is held in such a manner that its disconnection from the coupler jack is encumbered to prevent withdrawal without the use of a mechanical expedient. Forces must be applied to a tab of the plug in a particular manner to cause the tab to assume an essentially linear rather than a conventional arched configuration which occurs when the free end of the tab is depressed.

Abstract: A self-supporting aerial cable includes an undulated core enclosed in an aluminum, inner shield, a plastic inner jacket enclosed in a steel, outer shield having an unjoined longitudinal overlapped seam, and a plastic outer jacket. The outer plastic jacket includes a first portion which encloses the steel shield and a second portion which encloses a steel support strand that extends longitudinally but which is spaced from the first portion, said first and second portions of the outer jacket being connected by a web. The unjoined seam of the outer shield allows forces which are imparted to the steel shield by its formation to be transferred to the inner jacket and the inner shield which causes the inner shield to engage portions of the core to maintain the core coextensive with the inner and the outer jackets.

Abstract: A retractile telephone cord of this invention has a retractility which decreases substantially linearly from each end to a center of its length and an extensibility which increases substantially linearly from each end to a center of its length. The cordage includes a plurality of conductors which are individually insulated with a first plastic material and which are disposed in a planar array, and a jacket of a second plastic material which encloses the array. The jacket is formed about the array to provide a cross-section transversely of the cordage which includes at least one side that is parallel to the array. In making the retractile cord, a length of the cordage is wound helically about a mandrel with the one side of the cross-section of the cord being in engagement with the mandrel.

Abstract: A telephone station adapter includes a well-known ribbon-type connector having a modular jack at one end and supported from a hood which covers the connector and the jack. Because of testing procedures and because of the need to rearrange connections of conductors to contact elements of the ribbon-type connector, it becomes necessary to remove the hood without damaging it. This is accomplished with the tool of this invention in which the connector is supported in such a way that relative motion may be caused between it and a hood-removal portion of the tool. The hood-removal portion of the tool includes a portion which cams apart end sidewalls of the hood to disengage detents thereof from a body of the connector. The tool also includes a separating portion which causes the hood to be moved away from the connector once it has been disengaged and a prong which is moved into a cavity of the jack to hold the connector in engagement with a supporting surface while the hood is being removed.

Abstract: In the manufacture of a cable unit (30), which comprises a center portion and a plurality of layers of twisted conductor pairs, the pairs in the center portion and in each layer are oscillated in alternately opposite directions after which the unit is bound and taken up in a stationary container (62) by a system (100) which distributes the unit in a predetermined pattern of varying size convolutions. This distribution, which results in a dense package of a cable unit having a free end that facilitates testing of the unit during takeup, is accomplished while the speed at which the unit is being advanced and distributed into the varying size convolutions is maintained substantially constant.

Abstract: A drawn lightguide fiber is coated with a layer of a plastic material by moving the fiber through a container of the coating material and a die. The die is made of a relatively flexible material and is mounted so that a lower end extends through an opening of a diaphragm which is adapted to apply substantially coplanar forces to the lower end of the die to reduce the size of an exit orifice. The coating on the fiber is measured and if necessary, as a result of that measurement, the diaphragm is adjusted either manually or automatically to change the size of the die orifice and provide a coated fiber having a predetermined diameter.

Abstract: Methods are provided for making a composite article by successive molding steps. The article comprises an insert assembly that includes a metallic portion and a plastic locating framework in which the metallic portion is precisely mounted with respect to references points on the locating framework. The locating framework is mounted within a housing with the insert assembly precisely positioned with respect to the housing to cause the metallic portions to be substantially precisely positioned with respect to an exernal surface of the housing. In one embodiment, which is a hand tool that is moved slidably along a connector to sever conductors, a cutting blade is substantially precisely positioned in the locating framework of the insert assembly. Plastic is flowed about the framework in a mold cavity to form the housing.

Abstract: A work surface is supported for adjustment in a vertical direction by a device which includes a base and an angle post upstanding therefrom with a column mounted for sliding movement in engagement with the post. The work surface is mounted on an upper end of the column which is moved slidably by manual movement of a ratchet type mechanism and which is maintained in engagement with the post by an arrangement which provides for three dimensional as well as torsional stability. The work surface is provided with a further degree of mobility by mounting an axle and wheels on the base in such a way that the axle is moveable between a rest position in which the base rests on a floor and a mobile position in which the base is spaced above the floor by the wheels which ride thereon.

Abstract: A telephone connecting device which is capable of being mounted either within a wall to present a flush face plate in which is supported a modular jack for receiving a modular plug of a cord connected to station equipment or on an exterior surface of a wall includes a plastic receptacle which includes facilities for terminating a wall cable and for connecting the wall cable to the jack in the face plate. This permits a craftsperson during an initial visit to a home such as during construction to install a receptacle and to connect the wall cable to the terminating facilities within the receptacle. In order to have service, a customer acquires a face plate having a modular jack supported therein, connects conductors that are connected to contact elements of the jack to the terminating facilities and secures the face plate to the receptacle.

Abstract: A telephone cord which is particularly suited for use with some models of decorative telephones includes a plurality of individually insulated conductors, a plastic jacket which encloses the plurality of individually insulated conductors, and a braid which encloses the plastic jacket. While the braid is comprised of a woven band of cloth of a natural material or a synthetic material, in a preferred embodiment it is made of cotton which is dyed to a color which is compatible with that of portions of the decorative telephone. An end portion of the cord which is terminated with a modular plug that is capable of being inserted into a jack in the telephone is treated to cause the braid to be bonded to the plastic jacket so that when the jacket is removed to expose the conductors for purposes of plug termination, the braid will not fray.