Abstract:
A fiber optic cable includes an inner jacket and an outer jacket. The inner jacket surrounds an optical fiber and a strength layer positioned between the optical fiber and the inner jacket. The inner jacket includes a liquid crystal polymer within a base polymeric material. The outer jacket defines an elongate transverse cross-sectional profile. A strength member is positioned outside the inner jacket. The outer jacket is removable from the inner jacket such that the fiber optic cable forms a first cable portion that extends from a first end of the fiber optic cable to an intermediate location of the fiber optic cable and a second cable portion that extends from the intermediate location to a second end of the fiber optic cable. The first cable portion is more rugged than the second cable portion.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/056,394 entitled “Multi-jacketed Fiber Optic Cable” and filed on May 27, 2008, U.S. Provisional Patent Application Ser. No. 61/085,319 entitled “Multi-jacketed Fiber Optic Cable” and filed on Jul. 31, 2008 and U.S. Provisional Patent Application Ser. No. 61/179,604 entitled “Multi-jacketed Fiber Optic Cable” and filed on May 19, 2009. The above disclosures are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     As fiber to the home is extended into more and different living units, the cables used must provide more and more resistance to difficult installation requirements. In many cases, methods of installing cables made of copper are employed for fiber optic cables. The installation conditions and bend and impact rules are different as copper is a malleable metal and conducts electricity regardless of physical shape and does not degrade significantly under poor installation conditions. Optical fiber cables of small diameter must be protected against many new forms of installation abuse that do not affect copper drop cables. These include sensitivity to sharp bends and resistance to impacts such as flat staples installed along structural building components such as beams and trim boards. 
     SUMMARY 
     An aspect of the present disclosure relates to a fiber optic cable assembly including an inner cable assembly. The inner cable assembly includes an optical fiber, a first strength layer surrounding the optical fiber and a first jacket surrounding the strength layer. A second strength layer surrounds the inner cable assembly. The second strength layer includes strength members that are contra-helically served. The strength members are unbraided. A second jacket surrounds the second strength layer. 
     Another aspect of the present disclosure relates to a cable assembly. The cable assembly includes a fiber optic cable assembly having an inner cable assembly. The inner cable assembly includes an optical fiber, a first strength layer surrounding the optical fiber and a first jacket surrounding the strength layer. A second strength layer surrounds the inner cable assembly. The second strength layer includes a first set of strength members helically wrapped around the first jacket and a second set of strength members reverse helically wrapped around the first jacket. The first and second sets of strength members are unbraided. A second jacket surrounds the second strength layer. The cable assembly further includes a fiber optic connector engaged with an end of the fiber optic cable assembly. 
     Another aspect of the present disclosure relates to a cable assembly. The cable assembly includes a fiber optic cable assembly having an inner cable assembly. The inner cable assembly includes an optical fiber, a first strength layer surrounding the optical fiber and a first jacket surrounding the strength layer. A second strength layer surrounds the inner cable assembly. The second strength layer includes a first set of strength members helically wrapped around the first jacket and a second set of strength members reverse helically wrapped around the first jacket. The first and second sets of strength members are unbraided. A second jacket surrounds the second strength layer. The second jacket includes a base material having a plurality of reinforcing members embedded in the base material. The cable assembly further includes a fiber optic connector engaged with an end of the fiber optic cable assembly. 
     A variety of additional aspects will be set forth in the description that follows. These 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 concepts upon which the embodiments disclosed herein are based. 
    
    
     
       DRAWINGS 
         FIG. 1  is a perspective view of a cable assembly having exemplary features of aspects in accordance with the principles of the present disclosure. 
         FIG. 2  is an alternate perspective view of the cable assembly of  FIG. 1 . 
         FIG. 3  is a perspective view of a fiber optic cable assembly suitable for use in the cable assembly of  FIG. 1 . 
         FIG. 4  is perspective view of an optical fiber suitable for use in the fiber optic cable assembly of  FIG. 3 . 
         FIG. 5  is a perspective view of a second strength layer suitable for use in the fiber optic cable assembly of  FIG. 3 . 
         FIG. 6  is a cross-sectional view a fiber optic connector suitable for use with the cable assembly of  FIG. 1 . 
         FIG. 7  is a schematic representation of a cable puller pulling the cable assembly of  FIG. 1 . 
         FIG. 8  is a perspective view of the fiber optic cable assembly of  FIG. 3  in a bent orientation. 
         FIG. 9  is a schematic representation of a process suitable for manufacturing the cable assembly of  FIG. 1 . 
         FIG. 10  is a front view of a fiber optic drop cable assembly having features that are examples of aspects in accordance with the principles of the present disclosure. 
         FIG. 11  is a cross-sectional view of the fiber optic drop cable assembly taken on line  11 - 11  of  FIG. 10 . 
         FIG. 12  is a front view of an alternate embodiment of the fiber optic drop cable assembly of  FIG. 9 . 
         FIG. 13  is a cross-sectional view of the fiber optic drop cable assembly taken on line  13 - 13  of  FIG. 12 . 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the exemplary aspects of the present disclosure that are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like structure. 
     Referring now to  FIGS. 1 and 2 , a cable assembly, generally designated  4 , is shown. In the subject embodiment, the cable assembly  4  includes a connector  6  engaged to an end  8  of a fiber optic cable assembly, generally designated  10 . 
     Referring now to  FIG. 3 , the fiber optic cable assembly  10  includes an inner cable assembly, generally designated  12 . The inner cable assembly  12  includes at least one optical fiber, generally designated  14 , a buffer layer  16 , a first strength layer  18 , and a first jacket  20 . The fiber optic cable assembly  10  further includes a second jacket  22  disposed about the inner cable assembly  12 . 
     In the subject embodiment, the second jacket  22  of the fiber optic cable assembly  10  includes an outer diameter that can be sized to prevent or reduce the risk of damage (e.g., crushing, bending, etc.) to the optical fiber  14  during installation. However, as a cable configuration having a larger outer diameter can be difficult to install/route within a compact end location, such as a fiber optic enclosure, at least a portion of the second jacket  22  can be removed to expose the inner cable assembly  12  having a more compact cable configuration. 
     Referring now to  FIG. 4 , the optical fiber  14  of the inner cable assembly  12  is shown. The optical fiber  14  includes a core  24 . The core  24  is made of a glass material, such as a silica-based material, having a first index of refraction. In the subject embodiment, the core  24  has an outer diameter D 1  of less than or equal to about 10 μm. 
     The core  24  of the optical fiber  14  is surrounded by a cladding  26  that is also made of a glass material, such as a silica based-material. The cladding  26  defines a second index of refraction that is less than the first index of refraction defined by the core  24 . This difference between the first index of refraction of the core  24  and the second index of refraction of the cladding  26  allows an optical signal that is transmitted through the optical fiber  14  to be confined to the core  24 . In the subject embodiment, the cladding  26  has an outer diameter D 2  of less than or equal to about 125 μm. 
     A coating, generally designated  28 , surrounds the cladding  26 . The coating  28  includes an inner layer  30  and an outer layer  32 . In the subject embodiment, the inner layer  30  of the coating  28  is immediately adjacent to the cladding  26  such that the inner layer  30  surrounds the cladding  26 . The inner layer  30  is a polymeric material (e.g., polyvinyl chloride, polyethylenes, polyurethanes, polypropylenes, polyvinylidene fluorides, ethylene vinyl acetate, nylon, polyester, or other materials) having a low modulus of elasticity. The low modulus of elasticity of the inner layer  30  functions to protect the optical fiber  14  from microbending. 
     The outer layer  32  of the coating  28  is a polymeric material having a higher modulus of elasticity than the inner layer  30 . In the subject embodiment, the outer layer  32  of the coating  28  is immediately adjacent to the inner layer  30  such that the outer layer  32  surrounds the inner layer  30 . The higher modulus of elasticity of the outer layer  32  functions to mechanically protect and retain the shape of optical fiber  14  during handling. In the subject embodiment, the outer layer  32  defines an outer diameter D 3  of less than or equal to about 250 μm. In another embodiment, the outer diameter D 3  of the outer layer  32  is in the range of about 242 μm to about 245 μm. 
     In one embodiment, the optical fiber  14  is manufactured to reduce the sensitivity of the optical fiber  14  to micro or macro-bending (hereinafter referred to as “bend insensitive”). Exemplary bend insensitive optical fibers  14  have been described in U.S. Pat. Application Publication Nos. 2007/0127878 and 2007/0280615, now U.S. Pat. No. 7,623,747 and 7,587,111, respectively, are hereby incorporated by reference in their entirety. An exemplary bend insensitive optical fiber  14  suitable for use in the inner cable assembly  12  of the fiber optic cable assembly  10  of the present disclosure is commercially available from Draka Comteq under the name BendBright XS. 
     Referring again to  FIG. 3 , the buffer layer  16  is depicted as a tight layer that surrounds the optical fiber  14 . It will be understood, however, that the scope of the present disclosure is not limited to the buffer layer  16  being a tight layer. 
     The buffer layer  16  can have any number of conventionally known constructions. For example, the buffer layer  16  can be made of a polymeric material such as polyvinyl chloride (PVC). Other polymeric materials (e.g., polyethylenes, polyurethanes, polypropylenes, polyvinylidene fluorides, ethylene vinyl acetate, nylon, polyester, or other materials) may also be used. In the subject embodiment, the buffer layer  16  defines an outer diameter that is less than or equal to about 1 mm. In another embodiment, the outer diameter of the buffer layer  16  is less than or equal to about 900 μm. 
     The first strength layer  18  is adapted to inhibit axial tensile loading from being applied to the optical fiber  14 . In the subject embodiment, the first strength layer  18  extends the length of the fiber optic cable assembly  10  and is disposed in a generally longitudinal direction along the fiber optic cable assembly  10  between the buffer layer  16  and the first jacket  20 . In certain embodiment, the first strength layer  18  can include yarns, fibers, threads, tapes, films, epoxies, filaments or other structures. In a preferred embodiment, the first strength layer  18  includes a plurality of aramid yarns (e.g., KEVLAR® yarns). 
     In one embodiment, the plurality of aramid yarns includes an absorbent coating. When the absorbent coating is in contact with non-gaseous fluid (e.g., water), the absorbent coating absorbs the fluid. As the absorbent coating absorbs the fluid, outer diameters of the plurality of aramid yarns with the absorbent coating increase. This increase in the outer diameters of the plurality of aramid yarns blocks the axial and radial flow of non-gaseous fluid in the fiber optic cable assembly  10 . 
     The first jacket  20  surrounds the first strength layer  18 . In one embodiment, the first jacket  20  includes an outer diameter that is less than or equal to about 18 mm. In the subject embodiment, the first jacket  20  includes an outer diameter that is less than or equal to about 4 mm. In another embodiment, the outer diameter of the first jacket  20  is less than or equal to about 3.5 mm. In another embodiment, the outer diameter of the first jacket  20  is less than or equal to about 3 mm. 
     In the subject embodiment, the first jacket  20  includes a base material. In one embodiment, the base material is a polymer material such as a flexible chain polymer (i.e., one in which successive units of the polymer chain are free to rotate with respect to one another, so that the polymer chain can assume a random shape). Example base materials include conventional thermoplastic polymers such as polyethylene, polypropylene, ethylene-propylene, copolymers, polystyrene, and styrene copolymers, polyvinyl chloride, polyamide (nylon), polyesters such as polyethylene terephthalate, polyetheretherketone, polyphenylene sulfide, polyetherimide, polybutylene terephthalate, low smoke zero halogens polyolefins and polycarbonate, as well as other thermoplastic materials. Additives may also be added to the material. Example additives include pigments, fillers, coupling agents, flame retardants, lubricants, plasticizers, ultraviolet stabilizers or other additives. The base material can also include combinations of the above materials as well as combinations of other materials. 
     The second jacket  22  surrounds the first jacket  20 . In the subject embodiment, the second jacket  22  includes an outer diameter that is in the range of about 900 μm to about 20 mm. In another embodiment, the second jacket  22  includes an outer diameter that is less than or equal to about 6 mm. In another embodiment, the outer diameter of the second jacket  22  is about 5.5 mm. In another embodiment, the outer diameter of the second jacket  22  is about 5 mm. In another embodiment, the outer diameter of the second jacket  22  is about 3.6 mm. In another embodiment, the outer diameter of the second jacket  22  is about 3 mm. 
     In the subject embodiment, the second jacket  22  includes a polymer material such as a flexible chain polymer. Example polymer materials suitable for use for the second jacket  22  include conventional thermoplastic polymers such as polyethylene, polypropylene, ethylene-propylene, copolymers, polystyrene, and styrene copolymers, polyvinyl chloride, polyamide (nylon), polyesters such as polyethylene terephthalate, polyetheretherketone, polyphenylene sulfide, polyetherimide, polybutylene terephthalate, low smoke zero halogens polyolefins and polycarbonate, as well as other thermoplastic materials. Additives may also be added to the material. Example additives include pigments, fillers, coupling agents, flame retardants, lubricants, plasticizers, ultraviolet stabilizers or other additives. The base material can also include combinations of the above materials as well as combinations of other materials. In one embodiment, the material of the second jacket  22  is the same as the material of the first jacket  20 . In another embodiment, the material of the second jacket  22  is different than the material of the first jacket  20 . 
     In one embodiment, the first and/or second jacket  20 ,  22  has a structure that is adapted to resist post-extrusion shrinkage. For example, the first and/or second jacket  20 ,  22  may include a plurality of reinforcing materials embedded within the polymer material. An example of reinforcing materials embedded in the outer jacket of a fiber optic cable has been described in U.S. Pat. No. 7,379,642, the disclosure of which is hereby incorporated by reference in its entirety. 
     In one embodiment, the first and/or second jacket  20 ,  22  includes a plurality of discrete reinforcing members (e.g., rods, tendrils, extensions, fibers, etc.) embedded within the base material. In one embodiment, the reinforcing members are made from a material that can be softened and reshaped in the extrusion process. In a preferred embodiment, the reinforcing members include liquid crystal polymers. Example liquid crystal polymers are described in U.S. Pat. Nos. 3,991,014; 4,067,852; 4,083,829; 4,130,545; 4,161,470; 4,318,842; and 4,468,364, which are hereby incorporated by reference in their entireties. Liquid crystal polymers are polymers that are anisotropic and highly oriented, even in a softened or liquid phase. 
     The reinforcing members are preferably elongated and have lengths that are aligned generally parallel to a longitudinal axis of the fiber optic cable assembly  10 . Each of the reinforcing members preferably does not extend the entire length of the fiber optic cable assembly  10 . Instead, each of the reinforcing members preferably coincides with or extends along only a relatively short segment of the total length of the fiber optic cable assembly  10 . For example, in one embodiment, at least some of the reinforcing members have lengths in the range of 0.2 mm-100 mm. In another embodiment, at least some of the reinforcing members have lengths in the range of 5-60 mm. In still another embodiment, at least some of the reinforcing members have lengths in the range of about 10-40 mm. In certain embodiments, a majority of the reinforcing members provided within the base material can be within the size ranges provided above, or within other size ranges. Additionally, most of the reinforcing members are preferably discrete or separate from one another. For example, many of the reinforcing members are preferably separated or isolated from one another by portions of the base material. 
     To further promote flexibility, the concentration of the reinforcing members is relatively small as compared to the base material. For example, in one embodiment, the reinforcing material constitutes less than 2% of the total weight of the first and/or second jackets  20 ,  22 . In another embodiment, the reinforcing material constitutes less than 1.5% of the total weight of the first and/or second jackets  20 ,  22 . In still another embodiment, the reinforcing material constitutes less than or equal to 1.25% of the total weight of the first and/or second jackets  20 ,  22 . In a further embodiment, the reinforcing material constitutes less than or equal to 1.0% of the total weight of the first and/or second jackets  20 ,  22 . While preferred embodiments use less than 2% of the reinforcing material by weight, other embodiments within the scope of the present invention can use more than 2% by weight of the reinforcing material. 
     Referring now to  FIGS. 3 and 5 , in the subject embodiment, a second strength layer  34  is disposed between the second jacket  22  and the first jacket  20 . In one embodiment, the strength layer  34  is bonded to the first jacket  20 . In another embodiment, the strength layer  34  is bonded to the second jacket  22 . In another embodiment, the strength layer  34  is bonded to the first and second jackets  20 ,  22 . 
     The second strength layer  34  includes a plurality of strength members  36 . In the depicted embodiment of  FIG. 5 , only two strength members  36  are shown for ease of illustration purposes only. 
     The strength members  36  are disposed in two sets about the first jacket  20 . In the subject embodiment, the strength members  36  include a first set of strength members  36   a  and a second set of strength members  36   b . The second set of strength members  36   b  is disposed over the first set of strength members  36   a  such that the first and second sets of strength members  36   a ,  36   b  are unbraided or nonwoven. 
     In the subject embodiment, the first and second sets of strength members  36   a ,  36   b  are contra-helically served. For example, in the depicted embodiment of  FIG. 5 , the first set of strength members  36   a  is disposed about the first jacket  20  in a generally right-handed helical configuration while the second set of strength members  36   b  is disposed over the first set of strength members  36   a  in a generally left-handed helical configuration. The first and second sets of strength members  36   a ,  36   b  are disposed at angles α 1 , α 2  from a longitudinal line  37 . In one embodiment, the angles α 1 , α 2  are equal but opposite. In another embodiment, the angles α 1 , α 2  are in the range of about 0.1 degrees to about 20 degrees. In another embodiment, the angles α 1 , α 2  are in the range of about 5 degrees to about 20 degrees. In another embodiment, the angles α 1 , α 2  are in the range of about 0.1 degrees to about 15 degrees. In another embodiment, the angles α 1 , α 2  are in a range of about 1 degree to about 15 degrees. In another embodiment, the angles α 1 , α 2  are in the range of about 5 degrees to about 15 degrees. In another embodiment, the angles α 1 , α 2  are in a range of about 0.1 degrees to about 5 degrees. In another embodiment, the angles α 1 , α 2  are in a range of about 0.1 degrees to about 1 degree. This contra-helical orientation of the first and second sets of strength members  36   a ,  36   b  protects the fiber optic cable assembly  10  from twisting as the fiber optic cable assembly  10  is axially pulled by a cable puller. 
     In the subject embodiment, each of the strength members  36  has a lay length in a range of about 3 inches to about 18 inches. The lay length is the axial distance in which each of the strength members  36  wraps 360° around the first jacket  20 . 
     The first and second sets of strength members  36  define a plurality of openings  38 . In the subject embodiment, the openings  38  are generally diamond shaped. In one embodiment, an outwardly facing surface of the first jacket  20  bonds to an inner surface of the second jacket  22  through the plurality of openings  38  in the second strength layer  34 . 
     In one embodiment, the strength members  36  in the second strength layer  34  are strands of aramid yarn. In another embodiment, the strength members  36  are ribbonized fiberglass. In one embodiment, there are one to ten strength members  36  in the first set of strength members  36   a  and one to ten strength members  36  in the second set of strength members  36   b . In another embodiment, there are one to eight strength members  36  in the first set of strength members  36   a  and one to eight strength members  36  in the second set of strength members  36   b . In another embodiment, there are four strength members  36  in the first set of strength members  36   a  and four strength members  36  in the second set of strength members  36   b.    
     Referring now to  FIGS. 1 ,  2  and  6 , the connector  6  is shown. In the subject embodiment, the connector  6  is a multi-fiber connector. An exemplary multi-fiber connector suitable for use with the cable assembly  4  is disclosed in U.S. Pat. No. 5,214,730, the disclosure of which is hereby incorporated by reference in its entirety. Exemplary multi-fiber connectors suitable for use with the cable assembly  4  are available from US Conec Ltd. of Hickory, N.C., USA as part numbers C10821, C10822, C8190, and C10823. Fiber optic connectors related to part numbers C10821, C10822, C8190, and C10823 are known as MTP® connectors. 
     While the connector  6  is shown as a multi-fiber connector, it will be understood that the scope of the present disclosure is not limited to the connector  6  being of a multi-fiber type (e.g., MT, MTP, MPO, etc.) as the connector  6  could alternatively be of the single fiber type (e.g., SC, ST, LC, LX-5, etc.). 
     In the depicted embodiment of  FIGS. 1 ,  2  and  6 , the connector  6  includes a body  102  having a first axial end  104  and an oppositely disposed second axial end  106 . The body  102  defines a cavity  108  that extends through the first and second axial ends  104 ,  106 . The first axial end  104  is adapted for optical connection with a mating connector. The second axial end  106  is adapted for engagement with the fiber optic cable assembly  10 . 
     The connector  6  further includes a ferrule  110 . The ferrule  110  is disposed in the cavity  108  at the first axial end  104  of the body  102 . The ferrule  110  is adapted to receive the optical fiber  14  of the fiber optic cable assembly  10 . The ferrule  110  includes an end  112 . In the subject embodiment, the end  112  is generally rectangular in shape. The end  112  defines a plurality of termination locations  114  (shown schematically in  FIG. 2  as an “X”). In one embodiment, the end  112  defines twelve termination locations  114 . In another embodiment, the end  112  defines twenty-four termination locations  114 . 
     Each of the termination locations  114  is adapted to receive one of the optical fibers  14  of the fiber optic cable assembly  10 . In the subject embodiment the termination locations  114  are disposed in a single row on the end  112  of the ferrule  110  of the connector  6 . 
     The ferrule  110  further includes an alignment member  116 . In the subject embodiment, one alignment member  116  is disposed on each side of the end  112  of the ferrule  110 . In the subject embodiment, the alignment member  116  is an alignment pin. In another embodiment, the alignment member  116  is an alignment hole that is adapted to receive an alignment pin of a mating connector. 
     The connector  6  includes a release sleeve  118 . The release sleeve  118  includes a bore  120  that extends through the release sleeve  118 . The bore  120  of the release sleeve  118  is adapted to receive the body  102  of the connector  6 . The release sleeve  118  is disposed between the first and second axial ends  104 ,  106  of the body  102 . The release sleeve  118  is moveable between a latched position, in which the connector  6  is engaged to a fiber optic adapter, and a release position, in which the connector  6  is released from engagement with the fiber optic adapter. In one embodiment, a spring biases the release sleeve  118  to the latched position. 
     Referring now to  FIG. 6 , the second axial end  106  of the body  102  is adapted for engagement with the fiber optic cable assembly  10 . At least one of the first and second strength layers  18 ,  34  is engaged with the second axial end  106  of the body  102 . In the subject embodiment, the second strength layer  34  is engaged with the second axial end  106  of the body  102 . 
     In one embodiment, the second strength layer  34  is exposed by removing or stripping a portion of the second jacket  22 . The second strength layer  34  is then positioned around the second axial end  106  of the body  102 . A crimping tube  122  having a first end portion  124  and an opposite second end portion  126  is then disposed over the second axial end  106  of the body  102  such that the first end portion  124  is disposed over the second axial end  106  of the body  102  and the second strength layer  34  and the second end portion  126  is disposed over the second jacket  22 . The crimping tube  122  is then crimped such that the first end portion  124  crimps the second strength layer  34  to the second axial end  106  of the body  102  while the second end portion  126  is crimped to the second jacket  22 . 
     In the subject embodiment, a strain relief boot  130  is disposed over the crimping tube  122 . The strain relief boot  130  is adapted to protect the engagement between the fiber optic cable assembly  10  and the connector  6 . In one embodiment, the strain relief boot  130  is adapted to provide bend radius protection to the fiber optic cable assembly  10 . 
     As the outer diameter of the second jacket  22  is larger than the outer diameter of the first jacket  20 , the second jacket  22  of the fiber optic cable assembly  10  provides an added layer of protection to the optical fiber  14 . This added layer of protection is potentially advantageous during installation of the fiber optic cable assembly  10 . During installation of conventional cables, the outer jacket of the cable is grasped and used to pull an end of the cable to a desired location. At the location where the cable is grasped, the outer jacket of the cable is pinched. This pinching of the outer jacket may result in an optical fiber disposed within the jacket being pinched. In this situation, as the end of the cable is pulled to the desired location, the optical fiber may incur damage. The second jacket  22  of the fiber optic cable assembly  10  protects the optical fiber from being pinched by providing an additional layer of material. In another example, cables are often secured by a plurality of mounting structures such as staples. The second jacket  22  protects the optical fiber  14  from being crushed or damaged by the staples. 
     Referring now to  FIG. 7 , a simplified schematic representation of another exemplary use of the fiber optic cable assembly  10  is shown. In the depicted embodiment of  FIG. 7 , at least a portion of the fiber optic cable assembly  10  is disposed underground. In one embodiment, the fiber optic cable assembly  10  is directly buried underground. In another embodiment, the fiber optic cable assembly  10  is disposed in a conduit that is underground. 
     A cable puller  70  is connected to one end of the fiber optic cable assembly  10 . With the second strength layer  34  anchored to the cable puller  70 , the cable puller  70  pulls the fiber optic cable assembly  10  through the ground. As previously stated, the contra-helical orientation of the strength members  36  of the second strength layer  34  prevent the fiber optic cable assembly  10  from twisting as the cable puller  70  pulls the fiber optic cable assembly  10 . 
     Referring now to  FIG. 8 , in one embodiment, the outer diameter of the second jacket  22  prevents or reduces the risk of damage from kinking of the fiber optic cable assembly  10 . Kinking of the fiber optic cable assembly  10  occurs when the fiber optic cable assembly  10  is bent around about 180 degrees or more. If the radius of the second jacket  22  is larger than the minimum bend radius R of the optical fiber  14 , the second jacket  22  prevents the optical fiber  14  from being bent beyond the minimum bend radius R of the optical fiber  14  if the fiber optic cable assembly  10  is kinked. 
     The fiber optic cable assembly  10  of the present disclosure is potentially advantageous because it provides a rugged second jacket  22  that can be selectively removed to expose a more compact inner cable assembly  12 . In one embodiment, the second jacket  22  and the second strength layer  34  allow the fiber optic cable assembly  10  to be buried and pulled through the ground by a cable puller  70 . In another embodiment, the second jacket  22  provides added protection to the optical fiber  14  of the inner cable assembly  12  for installation. 
     Referring now to  FIG. 9 , a schematic representation of a system  200  for manufacturing the fiber optic cable assembly  10  will be described. The system  200  includes a crosshead, generally designated  202 , that receives thermoplastic material from an extruder  204 . A hopper  206  is used to feed materials into the extruder  204 . A first conveyor  208  conveys the base material to the hopper  206 . A second conveyor  210  conveys the shrinkage reduction material to the hopper  206 . The extruder  204  is heated by a heating system  212  that may include one or more heating elements for heating zones of the extruder  204  as well as the crosshead  202  to desired processing temperatures. 
     The inner cable assembly  12  is fed into a torque balanced yarn server  214  from a feed roll  216 . The torque balanced yarn server  214  contra-helically wraps the first and second sets of strength members  36   a ,  36   b  about the inner cable assembly  12 . The inner cable assembly  12  with the second strength layer  34  surrounding the inner cable assembly  12  is fed into the crosshead  202 . 
     A water trough  218  is located downstream from the crosshead  202  for cooling the extruded product that exits the crosshead  202 . The cooled final product is stored on a take-up roll  220  rotated by a drive mechanism  222 . A controller  224  coordinates the operation of the various components of the system  200 . 
     Referring now to  FIGS. 10 and 11 , a fiber optic drop cable assembly, generally designated  300 , is shown. In the depicted embodiment, the fiber optic drop cable assembly  300  is a generally flat cable assembly. It will be understood, however, that the scope of the present disclosure is not limited to the fiber optic drop cable assembly  300  being a generally flat cable assembly. 
     The fiber optic drop cable assembly  300  includes the inner cable assembly  12 . The inner cable assembly  12  includes the optical fiber  14 , the buffer layer  16 , the first strength layer  18 , and the first jacket  20 . 
     The fiber optic drop cable assembly  300  further includes a second jacket  302  disposed about the inner cable assembly  12 . The second jacket  302  has a width W and a thickness T. In the subject embodiment, the width W of the second jacket  302  is greater than the thickness T. The greater width W than thickness T of the second jacket  302  gives the fiber optic drop cable assembly  300  its generally flat cable appearance. 
     In the subject embodiment, the second jacket  302  of the fiber optic drop cable assembly  300  is a generally flat includes a polymer material such as a flexible chain polymer. Example polymer materials suitable for use for the second jacket  302  include conventional thermoplastic polymers such as polyethylene, polypropylene, ethylene-propylene, copolymers, polystyrene, and styrene copolymers, polyvinyl chloride, polyimide (nylon), polyesters such as polyethylene terephthalate, polyetheretherketone, polyphenylene sulfide, polyetherimide, polybutylene terephthalate, low smoke zero halogens polyolefins and polycarbonate, as well as other thermoplastic materials. Additives may also be added to the material. Example additives include pigments, fillers, coupling agents, flame retardants, lubricants, plasticizers, ultraviolet stabilizers or other additives. The base material can also include combinations of the above materials as well as combinations of other materials. In one embodiment, the material of the second jacket  302  is the same as the material of the first jacket  20 . In another embodiment, the material of the second jacket  302  is different than the material of the first jacket  20 . 
     The second jacket  302  defines a cable opening  304  that extends the length of the fiber optic cable assembly  300 . The cable opening  304  is sized to receive at least the inner cable assembly  12 . 
     At least a portion of the second jacket  302  of the fiber optic drop cable assembly  300  can be selectively removed to expose the inner cable assembly  12 . The second jacket  302  further defines a longitudinal split, generally designated  306 . In one embodiment, the longitudinal split  306  extends the length of the fiber optic drop cable assembly  300 . The longitudinal split  306  includes a first end  308  and an oppositely disposed second end  310 . 
     In the subject embodiment, a web  312  connects the first and second ends  308 ,  310  of the longitudinal split  306 . The web  312  acts as a line of weakness at which the second jacket  302  can be selectively opened. The web  312  is a thin strip of material having a thickness that is less than a thickness of the second jacket  302  between an outer surface of the second jacket  302  and the cable opening  304 . In the subject embodiment, the web  312  is made of the same material as the second jacket  302 . 
     In the subject embodiment, a ripcord  314  is disposed in the cable opening  304  between the first jacket  20  of the inner cable assembly  12  and the second jacket  302 . The ripcord  314  extends the length of the fiber optic drop cable assembly  300 . In the subject embodiment, the ripcord  314  is adapted to tear through the web  312  when subjected to a pulling force in a direction that is radially outward from the inner cable assembly  12 . As the ripcord  314  is pulled, the first and second ends  308 ,  310  of the longitudinal split  306  separate, thereby providing a location at which the inner cable assembly  12  can be removed from the second jacket  302 . 
     In one embodiment, the ripcord  314  is a polyester material. In another embodiment, the ripcord  314  is a nylon material. In another embodiment, the ripcord  314  is coated KEVLAR®. 
     Referring now to  FIGS. 12 and 13 , an alternate embodiment of the longitudinal split  306  is shown. The longitudinal split  306  includes the first end  308  and the second end  310 . In the subject embodiment, the first and second ends  308  and  310  are held closed by the inherent mechanical properties of the second jacket  302 , which bias the second jacket  302  to a closed position. In another embodiment, the first and second ends  308 ,  310  can be held in the closed position by a thermal weld. In another embodiment, the first and second ends  308 ,  310  can be held in the closed position by an adhesive or a bonding agent disposed on at least one of the first and second ends  308 ,  310 . 
     Referring again to  FIGS. 10 and 11 , the fiber optic drop cable assembly  300  further includes one or more reinforcing members  316 . The reinforcing members  316  are adapted to inhibit axial tensile and/or compressive loading from being applied to the inner cable assembly  12 . The reinforcing members  316  preferable extend the entire length of the fiber optic drop cable assembly  300 . In the subject embodiment, and by way of example only, the reinforcing members  316  include reinforcing rods (e.g., a glass reinforced plastic rod having glass rovings in an epoxy base, a metal rod, a liquid crystal polymer rod, etc.) that extend lengthwise along the entire length of the fiber optic drop cable assembly  300 . 
     Various modifications and alterations of this disclosure will become apparent to those skilled in the art without departing from the scope and spirit of this disclosure, and it should be understood that the scope of this disclosure is not to be unduly limited to the illustrative embodiments set forth herein.