Patent Publication Number: US-2019196129-A1

Title: Optical fiber furcation assemblies

Description:
FIELD 
     The present disclosure relates generally to furcation assemblies for furcating optical fibers of multiple fiber cables. 
     BACKGROUND 
     The ability of high-quality optical fiber to transmit large amounts of information without appreciable signal degradation is well known. As a result, optical fibers have found widespread use in many applications, such as voice and data transmission. Particularly in the private network and industrial markets, there is a continuing trend in which copper-based wiring is being replaced with fiber optic cabling for communication and sensing applications. 
     Optical fiber is typically supplied and installed as fiber optic cable. The term “fiber optic cable” refers to the combination of the actual optical fiber plus the structure in which it is carried and protected during and after installation. A fiber optic cable may include, for example, optical fiber(s), aramid fibers or other strength members, and an outer jacket. Multiple optical fibers are often combined in a multi-fiber cable. Multi-fiber cables efficiently carry the requisite number of fibers to the point(s) of applied use, where it is then necessary to separate each individual optical fiber and terminate the individual optical fibers with fiber optic connectors. 
     Furcation assemblies generally serve as a means to facilitate the separation of optical fibers of multi-fiber cables by providing a protective housing for transitioning the individual optical fibers from the multi-fiber cable. However, improvements could be made to currently known furcation assembly designs. 
     For example, one issue with many known furcation assembly designs is that the multi-piece designs are complicated to assemble. In particular, in many cases it is easy for users to assemble certain components in incorrect orientations. Such incorrect assemblies can expose the optical fibers to contaminates due to the assemblies not sealing properly, or can delay the assembly time once the user realizes that the assembly is incorrect. Further, users in many cases are required to assemble the components in a certain specific order, and must start over or provide an unfinished assembly if such order is not followed. 
     Another issue is that many furcation assemblies are designed to fit a very narrow range of input cable sizes. Accordingly, many different varieties of furcation assemblies are required for different input cable sizes. 
     Accordingly, improved furcation assemblies are desired. 
     BRIEF DESCRIPTION 
     Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention. 
     In accordance with embodiments of the present disclosure, a furcation assembly is disclosed for furcating a multiple fiber cable. The furcation assembly defines a longitudinal axis. The furcation assembly includes a body defining a furcation block receiving portion and a cable receiving portion, the body including a longitudinally extending rail. The furcation assembly further includes a furcation block positioned within the furcation block receiving portion, and a cable retainer disposed within the cable receiving portion. The furcation assembly further includes a housing receivable around the body such that the furcation block and cable retainer are disposed within the housing, the housing defining an interior and a longitudinally extending slot. The rail extends into the slot when the housing is received around the body. 
     In accordance with other embodiments of the present disclosure, a furcation assembly is disclosed for furcating a multiple fiber cable. The furcation assembly defines a longitudinal axis. The furcation assembly includes a body defining a furcation block receiving portion and a cable receiving portion. The furcation assembly further includes a furcation block positioned within the furcation block receiving portion, and a cable retainer disposed within the cable receiving portion. The cable retainer includes a crimp wing crimpable into contact with the multiple fiber cable to retain the multiple fiber cable, the crimp wing including a burr. The furcation assembly further includes a housing receivable around the body such that the furcation block and cable retainer are disposed within the housing. 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION 
       A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: 
         FIG. 1  is a perspective view of a furcation assembly assembled with and furcating a multiple fiber cable in accordance with embodiments of the present disclosure; 
         FIG. 2  is a top perspective view of a furcation assembly in accordance with embodiments of the present disclosure; 
         FIG. 3  is a bottom perspective view of a furcation assembly in accordance with embodiments of the present disclosure; 
         FIG. 4  is a top perspective view of a furcation assembly with a housing shown exploded from a body thereof in accordance with embodiments of the present disclosure; 
         FIG. 5  is a top perspective view of a body and cable retainer of a furcation assembly in accordance with embodiments of the present disclosure; and 
         FIG. 6  is a close-up top perspective view of a body and cable retainer of a furcation assembly in accordance with embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
     In general, the present disclosure is directed to furcation assemblies which include various advantageous features for improving the furcation of multiple fiber cables. 
     For example, in some embodiments, furcation assemblies in accordance with the present disclosure include features which facilitate the correct orientation of the various components of the furcation assembly during the assembly process thereof and eliminate the need for a specific assembly order to be followed. In particular, for example, a furcation assembly may include a body having a rail, and a cover having a slot, wherein the rail extends into the slot when the cover is received around the body in an assembled state. Because the rail must fit into the slot for the body and cover to fit together, correct orientation of these components is ensured. Further, having such slot in the cover eliminates the need for the cover to be installed on a cable before other assembly steps, such as installing fibers of the cable in a furcation block and securing the cable to the furcation assembly. The use of such slot allows the cover to advantageously be installed on the cable either before or after such other assembly steps occur. 
     In additional or alternative embodiments, furcation assemblies in accordance with the present disclosure include features which allow for increased flexibility in the size range of multiple fiber cable with which such furcation assemblies may be utilized. Such features may additionally provide improved security in the manner in which such cables are retained by the furcation assemblies. In particular, for example, a furcation assembly may include a cable retainer which includes one or more crimp wings. The crimp wings are crimpable into contact with the multiple fiber cable, and may include burrs which contact the multiple fiber cable when the crimp wings are crimped into such contact. 
     Referring now for example to  FIG. 1 , a multiple fiber cable  10  is illustrated. The multiple fiber cable  10  includes an outer jacket  12  and a plurality of optical fibers  14  extending from an end  13  of the outer jacket  12 . As discussed herein, the optical fibers  14  may be inserted through a furcation block and from the furcation block into furcation tubes  20 . Each furcation tube  20  may house one or more optical fibers  14 , and may serve to protect the furcated optical fibers  14 , as is generally understood. 
     Referring still to  FIG. 1  as well as to  FIGS. 2 through 6 , furcation assemblies  100  are provided for furcating such multiple fiber cables  10 . A furcation assembly  100  in accordance with the present disclosure may generally define a longitudinal axis  102 , a vertical axis  104 , and a transverse axis  106 , all of which may be mutually orthogonal to define a coordinate system for the assembly  100 . 
     Furcation assembly  100  may include a body  110  which extends along the longitudinal axis  102 . Body  110  includes a furcation block receiving portion  112  and a cable receiving portion  114 . Such portions  112 ,  114  are spaced apart along the longitudinal axis  102  and generally included within an interior of the body  110 . 
     The body  110  may further include a plurality of arms  116 , such as in exemplary embodiments a pair of arms  116 . The arms  116  may be oppositely positioned relative to the body  110  along the transverse axis T, and may be biased outward from the body  110  along the transverse axis T. As discussed herein, the arms  116  may connect with mating apertures in a housing of the furcation assembly  100  when the housing is received around the body  110 . 
     The body  110  may further include a plurality of stacking members  120 , which may for example, be disposed at a longitudinal end of the body  110  which is distal from the end at which the cable  10  enters the body  110 . Each stacking member  120  may serve to facilitate stacking of multiple furcation assemblies  110  on top of one another, such as along the vertical axis  104 . Each stacking member  120  may include, for example, a pin  122  and a socket  124 . The pin  122  and socket  124  may be disposed on opposite ends of the stacking member  120  along the vertical axis  104 . The pin  122  may be inserted in the socket of a neighboring furcation assembly during stacking thereof. Similarly, the socket  124  may accept the pin  124  of a neighboring furcation assembly during stacking thereof. 
     Furcation assembly  100  may further include a furcation block  130 . The furcation block  130  may define a plurality of furcation holes  132  through which optical fibers  14  extend when the furcation assembly  100  is assembled on a cable  10 . Such furcation holes  132  may extend along the longitudinal axis  102 . Furcation block  130  may be positioned within the furcation block receiving portion  112 . In some embodiments, the furcation block  130  may be removable positionable within the furcation block receiving portion  112 , and thus may be a separate component from the body  110 . In other embodiments, the furcation block  130  may be fixedly positioned within the furcation block receiving portion  112 , and in some embodiments may be integral with the body  110  such that the body  110  and furcation block  130  are formed as a single, unitary component. 
     In some embodiments, such as in embodiments wherein the furcation block  130  is separate and removable from the body  110 , the body  110  may further include one or more tabs  128 , such as in exemplary embodiments a plurality of tabs  128 . Each tab  128  may extend into the furcation block receiving portion  112 . Further, each tab  128  may secure the furcation block  130  when positioned within the furcation block receiving portion  112 . For example, the furcation block  130  may be inserted into the furcation block receiving portion  112  along the vertical axis  104  past the tabs  128 , which may then contact a top surface of the furcation block  130  to secure the furcation block in the furcation block receiving portion  112 . Alternatively, the furcation block  130  may be inserted into the furcation block receiving portion  112  along the longitudinal axis  102  under the tabs  128 , which may then contact a top surface of the furcation block  130  to secure the furcation block in the furcation block receiving portion  112 . 
     Furcation assembly  100  may further include a cable retainer  140 , which may be disposed within the cable receiving portion  114 . Cable retainer  140  may contact and retain the cable  10 , such as the outer jacket  12  thereof, within the furcation assembly  100  when the furcation assembly  100  is assembled on the cable  10 . In exemplary embodiments, the cable retainer  140  may be fastened to the body  110  in the cable receiving portion  114 . For example, the cable retainer  140  may in some exemplary embodiments be ultrasonically fed to the body  110  in the cable receiving portion  114 . As shown, in some ultrasonic welding embodiments, posts  126  are provided in body  110 , such as in the cable receiving portion  114  thereof. The posts  126  may, for example, extend along the vertical direction  102 . Holes  142  may be defined in the cable retainer  140 , and the posts  126  may be inserted through the holes  142  to seat the cable retainer  140  within the cable receiving portion  114 . The posts  126  may then be ultrasonically melted to ultrasonically weld the cable retainer  140  to the body  110  within the cable receiving portion  114 .  FIG. 4  illustrates the posts  126  before ultrasonic welding thereof, and  FIGS. 5 and 6  illustrate the posts  126  after such ultrasonic welding. 
     In some exemplary embodiments, the cable retainer  140  includes one or more crimp wings  144 , which may extend from a base  146 . The base  146  may define the holes  142 . In some exemplary embodiments, one or more pairs of crimp wings  144  are provided. Each crimp wing  144  may be crimpable into contact with the cable  10  to retain the cable  10 . For example, during assembly, the cable  10 , such as the outer jacket  12  thereof, may be placed in cable receiving portion  114  and in contact with the cable retainer  140 . In exemplary embodiments, the cable  10 , such as the outer jacket  12  thereof, may be placed between the crimp wings  144  of one or more pairs of crimp wings  144 . The crimp wings  144  may then be bent or otherwise crimped into contact with cable  10  to secure the cable  10  in the cable receiving portion  114 . For example, in exemplary embodiments each pair of crimp wings  144  captures the cable  10  between the crimp wings  144  thereof. 
     In some exemplary embodiments, one or more crimp wings  144  includes a burr  148  extending therefrom. Burr  148  is generally a protrusion extending inwardly from a crimp wing  144 . For example, in exemplary embodiments as shown, burr  148  is formed by forming a hole in a crimp wing  144 , whereby the portion of the crimp wing  144  forming the area in which the hole is formed then forms a burr  148 . When a crimp wing  144  contacts a cable  10 , such as the outer jacket  12  thereof, the burr  148  may serve to further facilitate securing of cable  10  in the cable receiving portion  114  by contacting and in some embodiments embedding into the outer jacket  12 . 
     Furcation assembly  100  may further include a housing  150  which is receivable around the body  110 . For example, when the housing  150  is received around the body  110 , the furcation block receiving portion  112  and cable receiving portion  114  may be disposed within the housing  150 , such as in an interior  152  defined by the housing  150 . Further, the furcation block  130  and cable retainer  140  may be disposed within the housing  150 , such as in the interior  152 . 
     Housing  150  may be received around the body  110  along the longitudinal axis  102 . For example, the housing  150  may be slid in the longitudinal axis  102  over the body  110  until the furcation block receiving portion  112  and cable receiving portion  114  may be disposed within the housing  150 . In some embodiments, the stacking members  120  are exposed and thus not disposed within housing  150 . 
     In exemplary embodiments, housing  150  is a one-piece housing. Alternatively, however, housing  150  may be formed from two or more pieces. 
     Housing  150  may have a first end and a second end which are separated from each other along the longitudinal axis  102  and which define a first end opening  154  and second end opening  156  respectively. When assembled, the cable  10  (such as the outer jacket  12  thereof) may extend through the first end opening  154 . Further, the furcated optical fibers  14  and furcation tubes  20  may extend through the second opening  156 . 
     In some embodiments, housing  150  may further define one or more apertures  158 , such as in exemplary embodiments a plurality of apertures  158 . Apertures  158  may be disposed between the first and second end openings  154 ,  156 , respectively. Further, the apertures  158  may be oppositely positioned relative to the housing  150  along the transverse axis T. Each aperture  158  may interact with an arm  116 , such as the distal end  117  thereof, to securely connect the housing  150  to the body  110  when the housing  150  is received around the body  110 . For example, the distal end  117  of each arm  116  may extend into an aperture  158  when the housing  150  is received around body  110 , and this insertion of the distal ends  117  into the apertures  158  may removably secure the housing  150  to the body  110 . 
     In exemplary embodiments, the body  110  may further include a rail  160 . Rail  160  may extend along the longitudinal axis  102 . Further, in some exemplary embodiments, rail  160  may be a base rail which is located on the bottom of the body  110  along the vertical axis  104 . Alternatively, rail  160  may be a side rail which is located on a side of the body  110  along the transverse axis  106 , or a top rail which is located on the top of the body  110  along the vertical axis  104 . 
     Rail  160  may serve to orient the housing  150  relative to the body  110 , thus ensuring that the housing  150  is received around the body  110  in the correct orientation. To facilitate such orientation, housing  150  may define a slot  162  which extends along the longitudinal axis  102 . Slot  162  may, for example, extend from the first end opening  154  to the second end opening  156 , and thus extend along the entire longitudinal length of the housing  150 . When the housing  150  is being assembled onto the body  110  in the correct orientation, the rail  160  may be inserted into the slot  162 . Accordingly, the rail  160  may extend into the slot  162  when the housing  150  is received around the body  110 . However, when the housing  150  is being assembled onto the body  110  but is not in the correct orientation, the rail  160  may not be aligned with the slot  162 , and may further contact the housing  150  and prevent the housing  150  from being received around the body  110 . Accordingly, correct orientation of the housing  150  relative to the body  110  is facilitated via alignment of the rail  160  and slot  162 . 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.