Abstract:
A fiber optic cable includes first and second fiber optic cables segments that are joined at an in-line splice location at which a fiber optic splice is located. The in-line splice location includes a strain transference arrangement configured to inhibit strain from being transferred to the fiber optic splice.

Description:
CROSS REFERENCE 
       [0001]    This application claims priority to U.S. Provisional Patent Application Ser. No. 60/948,792, filed on Jul. 10, 2007, the disclosure of which is hereby incorporated by reference herein. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates generally to a fiber optic data transmission system. More particularly, the present disclosure relates to splice configurations for use with fiber optic data transmission systems. 
       BACKGROUND 
       [0003]    Fiber optic cables are widely used to transmit light signals for high speed data transmission. A fiber optic cable typically includes: (1) an optical fiber or optical fibers; (2) a buffer or buffers that surrounds the fiber or fibers; (3) a strength layer that surrounds the buffer or buffers; and (4) an outer jacket. Optical fibers function to carry optical signals. A typical optical fiber includes an inner core surrounded by a cladding that is covered by a coating. Buffers (e.g., loose or tight buffer tubes) typically function to surround and protect coated optical fibers. Strength layers add mechanical strength to fiber optic cables to protect the internal optical fibers against stresses applied to the cables during installation and thereafter. Example strength layers include aramid yarn, steel, and epoxy reinforced glass roving. Outer jackets provide protection against damage caused by crushing, abrasions, and other physical damage. Outer jackets also provide protection against chemical damage (e.g., ozone, alkali, acids). 
         [0004]    Fusion splices are often used in fiber optic communication systems to provide a fiber optic connection between two optical fibers. Typically, fiber optic splices are protected within splice sleeves. A typical splice sleeve includes a polymeric tube reinforced with a stainless steel reinforcing member. Splice sleeves containing splices are typically protected and managed in auxiliary structures such as splice trays, enclosures, or other types of splice holders. 
       SUMMARY 
       [0005]    One aspect of the present disclosure relates to a fiber optic splice configuration in which a splice protection sleeve is stored in-line with a fiber optic cable. The splice storage location includes structure for providing strain relief to the splice. 
         [0006]    A variety of additional inventive aspects will be set forth in the description that follows. The inventive aspects can relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the embodiments disclosed herein are based. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is an assembled view of a fiber optic cable including an in-line splice location having features that are examples of inventive aspects in accordance with the principles of the present disclosure; and 
           [0008]      FIG. 2  is an exploded view of the fiber optic cable of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0009]      FIGS. 1 and 2  depict a fiber optic cable  20  having an in-line splice location  22  including features that are examples of inventive aspects in accordance with the principles of the present disclosure. Generally, the fiber optic cable  20  includes first and second segments  24   a ,  24   b  that are mechanically and optically coupled at the in-line splice location  22 . The segments  24   a ,  24   b  include optical fibers  26   a ,  26   b  that are spliced at the in-line splice location  22  to provide an optical coupling between the fibers  26   a ,  26   b . In one embodiment, the optical fibers  26   a ,  26   b  can each include a core defining an outer diameter of about 10 microns, a cladding layer covering the core and defining an outer diameter of about 125 microns, one or more protective coatings that cover the cladding and define an outer diameter of about 250 microns, and a buffer layer that covers the coating layers and defines an outer diameter of about 900 microns. 
         [0010]    The first and second segments  24   a ,  24   b  also can include outer jackets  28   a ,  28   b  that cover the buffer layers, and reinforcing/strength layers  30   a ,  30   b  (e.g., layers of reinforcing material, such as aramid yarn (i.e., KEVLAR®), steel, epoxy-reinforced glass roving, or other materials positioned between the jackets  28   a ,  28   b  and the buffer layers). In one embodiment, the outer jacket  28   a ,  28   b  can each have an outer diameter of about 2 to 3 millimeters. As shown at  FIGS. 1 and 2 , one end of the first segment  24   a  is connectorized with a fiber optic connector  25 , such as a standard SC connector. 
         [0011]    The optical fibers  26   a ,  26   b  are preferably fusion spliced at the in-line splice location  22 . As shown at  FIG. 2 , buffer layers  32   a ,  32   b  have been stripped from the ends of the optical fibers  26   a ,  26   b  to expose coated end portions  34   a ,  34   b  of the optical fibers  26   a ,  26   b . In one embodiment, the coated end portions  34   a ,  34   b  are fused together and protected within a splice protection sleeve  36 . In other embodiments, the coatings can be stripped as well prior to splicing the end portions together. In one embodiment, the splice protection sleeve  36  can include a polymeric tube that is reinforced with a reinforcing member such as a stainless steel layer. The splice protection sleeve  36  is mounted within an outer tube  38 . Preferably, the splice protection sleeve  36  is free to move or float linearly within the outer tube  38 . In one embodiment, the outer tube  38  can have a polymeric construction. However, it will be appreciated that other materials could be used as well. 
         [0012]    Still referring to  FIG. 2 , strength layer attachment members  40   a ,  40   b  are mounted at opposite ends of the outer tube  38 . In certain embodiments, the strength layer attachment members  40   a ,  40   b  can be glued to the ends of the outer tube  38 , press fit within the ends of the outer tube  38 , or otherwise mechanically secured to the ends of the outer tube  38 . As shown in  FIG. 2 , the strength layer attachment members  40   a ,  40   b  have a textured (e.g., knurled) outer surface that facilitates securing the strength layers  30   a ,  30   b  of the segments  24   a ,  24   b  to opposite ends of the outer tube  38 . In one embodiment, the reinforcing layers  30   a ,  30   b  (e.g., KEVLAR® layers) can be crimped, glued, or otherwise secured to their respective strength layer attachment members  40   a ,  40   b.    
         [0013]    When the fiber optic cable  20  is assembled, the in-line splice location  22  is positioned in-line with the first and second segments  24   a ,  24   b . In this way, the splice protection sleeve  36  is stored and protected within the cable itself. By attaching the strength layers  30   a  to the strength layer attachment member  40   a  and the strength layer  30   b  to the strength layer attachment location  40   b , strain is prevented from being transferred to the splice through the cable. For example, if a field technician pulls on the connectorized end of the segment  24   a , strain is transferred from the strength layer  30   a  through the tube  38  to the strength layer  30   b . In this way, the strength layer attachment locations  40   a ,  40   b  allow the tube  38  to function as a mechanical shunt that prevents strain from being transferred to the splice within the splice sleeve  36 . Boots  42  can be provided at the ends of the in-line splice location  22  (e.g., over the strength layer attachment locations  40   a ,  40   b ) to provide enhanced bend protection. 
         [0014]    From the foregoing detailed description, it will be evident that modifications and variations can be made in the devices of the disclosure without departing from the spirit or scope of the invention.