Abstract: Methods of and apparatus for winding strand such as optical fibers on altate spools and for storing and protecting from damage coiled end portions of the strand to be wound on the spools in which the coils are clamped laterally of the coils with forces applied parallel to the axis of the coils. The methods and apparatus of the invention may be used for urging portions of the strand being fed to the spools and associated strand storage and clamping devices against the peripheral surfaces thereof to aid in the transfer of the distribution of the strand from one spool to the other spool.

Abstract: Methods of and apparatus are provided for winding strand such as optical ers on alternate spools and for storing and protecting from damage coiled end portions of the strand to be wound on the spools in which the coils are clamped laterally of the coils with forces applied parallel to the axis of the coils. The methods and apparatus of the invention may be used for urging portions of the strand being fed to the spools and associated strand storage and clamping devices against the peripheral surfaces thereof to aid in the transfer of the distribution of the strand from one spool to the other spool.

Abstract: A spool (20) which is used in the taking up and the paying out of a relatively long length of optical fiber includes two flanges (24, 26) and a hub (22) with each flange being tapered. The spool includes a collector (30) which is formed adjacent to one of the two tapered flanges of the spool and which provides access to the initial or leading end portion of the length of optical fiber which is wound on the spool. A groove (32) of the collector communicates with the hub of the spool through each of the two diametrically opposed slots (28--28) in the adjacent tapered flange (24). This allows the optical fiber to be wound on one of two coaxially mounted spools and to be transferred to the other spool with the first few convolutions being received in the groove and then passed through one of the slots in the adjacent tapered flange onto the hub.

Abstract: An induction furnace (60) for reflowing a portion of an optical preform (12) in order to draw a lightguide fiber (11) therefrom includes a tubular susceptor (80) which is disposed centrally within a beaker (75) and a sleeve (82) which is disposed concentrically about the susceptor. The sleeve is spaced from the susceptor and is surrounded by insulating grain (83). A high frequency coil (84) is energized to couple its electromagnetic field to the susceptor to heat and reflow a portion of the preform. The movement of contaminating particles of the insulating grain into the interior of the susceptor is prevented substantially by annular, felt-like discs (91, 105) at the bottom and top of the beaker. The discs collect particulates which move downwardly and upwardly and because of their compliant engagement with the beaker and with the sleeve, they provide seals at those interfaces.

Abstract: A technique for dynamically transferring a lightguide fiber (10) from a full spool (18) to an empty spool (19) as both spools rotate at the same velocity and the input velocity of the fiber is constant. The lightguide fiber (10) is wound onto the rotating spool (18) in such a manner as to form a package of wound material having a conically tapered section (52) when full. The fiber (10) is then wound along the tapered section (52) as the velocity of the spools (18 and 19) are increased. When the fiber (10) is at the diameter of the tapered section (52) which is equal to the diameter of the empty spool, it is transferred to the empty spool without any substantial loss of fiber spooling control.

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: In taking up drawn lightguide fiber (31), the fiber is distributed on the hub of one of two coaxially mounted takeup spools 42-42 which are driven independently of each other at ends of indexable turrets (94-94) that also have spools mounted on their opposite ends. Following takeup on one of the spools, a distributor 201 effects a cutover to a collector groove of the adjacent spool until several convolutions of the fiber are secured within the collector groove to provide access to a leading end of the fiber on this spool for testing purposes. Then the distributor begins its traverse across the hub of the empty spool and the lightguide fiber which extends across the adjacent collector spools is severed to form an end portion on the spool now being filled, said end portion advantageously being accessible for testing.