Abstract:
A single piece hub and ferrule assembly for a fiber optic connector includes: a first portion sized to receive a jacket of a fiber optic cable; a second portion sized to receive a fiber of the fiber optic cable; and a hub portion configured to engage a housing of the fiber optic connector; wherein the first portion, the second portion, and the hub portion are all formed as an integrally-molded piece.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is being filed on 25 Oct. 2013, as a PCT International Patent application and claims priority to U.S. Patent Application Ser. No. 61/718,218 filed on 25 Oct. 2012, the disclosure of which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    Fiber optic cables are used in the telecommunication industry to transmit light signals in high-speed data and communication systems. A standard fiber optic cable includes a fiber with an inner light transmitting optical core. Surrounding the fiber is an outer protective casing. 
         [0003]    A fiber terminates at a fiber optic connector. Connectors are frequently used to non-permanently connect and disconnect optical elements in a fiber optic transmission system. There are many different fiber optic connector types. Some of the more common connectors are LC, FC, and SC connectors. Other types of connectors include ST and D4-type connectors. 
         [0004]    A typical fiber optic connector, such as an SC connector, includes a housing having a front end positioned opposite from a rear end. The front end of the connector housing is commonly configured to be inserted within an adapter. An example adapter is shown in U.S. Pat. No. 5,317,663, assigned to ADC Telecommunications, Inc. The connector typically further includes a ferrule that is positioned within the front and rear ends of the housing, and adjacent the front end. The ferrule is axially moveable relative to the housing, and is spring biased toward the front of the connector. The fiber optic cable has an end that is stripped. The stripped end includes a bare fiber that extends into the connector and through the ferrule. 
         [0005]    A connector, such as the connector described above, is mated to another connector within an adapter like the adapter of U.S. Pat. No. 5,317,663. A first connector is received within the front portion of the adapter, and a second fiber is received within the rear portion of the adapter. When two connectors are fully received within an adapter, the ferrules (and hence the fibers internal to the ferrule) contact or are in close proximity to each other to provide for signal transmission between the fibers. Another connector type (LX.5 connector) and mating adapter is shown in U.S. Pat. No. 6,142,676, assigned to ADC Telecommunications, Inc. 
       SUMMARY 
       [0006]    In one aspect, a single piece hub and ferrule assembly for a fiber optic connector includes: a first portion sized to receive a jacket of a fiber optic cable; a second portion sized to receive a fiber of the fiber optic cable; and a hub portion configured to engage a housing of the fiber optic connector; wherein the first portion, the second portion, and the hub portion are all formed as an integrally-molded piece. 
         [0007]    In another aspect, a fiber optic connector includes: a front housing; a rear housing; a single piece hub and ferrule assembly, the single piece hub and ferrule assembly including: a first portion sized to receive a jacket of a fiber optic cable; a second portion sized to receive a fiber of the fiber optic cable; and a hub portion configured to engage the front housing of the fiber optic connector; and a spring positioned in the fiber optic connector to push the single piece hub and ferrule assembly towards the front housing. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is an exploded view of an example fiber optic connector. 
           [0009]      FIG. 2  is a side view of the connector of  FIG. 1  in a fully assembled state. 
           [0010]      FIG. 3  is a cross-sectional view taken along line A-A of the connector shown in  FIG. 2 . 
           [0011]      FIG. 4  is a cross-sectional view taken along line E-E of the connector shown in  FIG. 3 . 
           [0012]      FIG. 5  is a side view of a one piece hub and ferrule assembly of the connector shown in  FIG. 1 . 
           [0013]      FIG. 6  is an end view of the one piece hub and ferrule assembly shown in  FIG. 5 . 
           [0014]      FIG. 7  is a cross-sectional view taken along line H-H of the one piece hub and ferrule assembly shown in  FIG. 5 . 
           [0015]      FIG. 8  is another cross-sectional view taken along line H-H of the one piece hub and ferrule assembly shown in  FIG. 6  including a fiber optic cable. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    The present disclosure is directed towards fiber optic connectors. Although not so limited, an appreciation of the various aspects of the present disclosure will be gained through a discussion of the examples provided below. 
         [0017]      FIG. 1  is an exploded view of an example connector  100 . In this example, the connector  100  is an LC connector, although other connector types can be used. The connector  100  includes a front housing  110 , a rear housing  140 , and a boot  150 . 
         [0018]    The connector  100  further includes an insertion cap  142  and a crimp sleeve  324 . The crimp sleeve  324  is inserted over a rear portion of the rear housing  140  and captures the insertion cap  142  therebetween. The crimp sleeve  324  is used to crimp the cable  101 . Addition details regarding an LC connector configured in a similar manner are provided in U.S. patent application Ser. No. 13/420,286 filed on Mar. 14, 2012, the entirety of which is hereby incorporated by reference. 
         [0019]    Also included is a hub/ferrule assembly  120  with a hub  122  and a ferrule  124 . The hub  122  includes an anti-rotation portion  128  and an elongated cylindrical rear portion  123 . The hub  122  is connected to the ferrule  124 , such as with adhesive or with an interference fit. A spring  130  is also provided. A fiber optic cable  101  is shown including a fiber  102  and a jacket  103 . 
         [0020]    In  FIGS. 2 and 3 , the connector  100  is shown in a fully assembled state. 
         [0021]    The front housing  110  of the connector  100  extends along a longitudinal axis  200  and defines an anti-rotation seat  112  and a cavity  114 . The ferrule  124  extends through a front bore  116  of the front housing  110 . The anti-rotation portion  128  of the hub  122  is slidingly engaged along the longitudinal axis  200  in the anti-rotation seat  112 . 
         [0022]    In the example embodiment, the anti-rotation portion  128  is shaped in a hexagonal configuration (see  FIGS. 5-8 ) and the anti-rotation seat  112  defines a seat of a complementary geometry. Knobs  180  and  181  form the anti-rotation seat  112  (see  FIG. 4 ). The anti-rotation portion  128  and the anti-rotation seat  112  allow for sliding along the longitudinal axis  200 , but prevent relative rotation. Specifically, the anti-rotation portion  128  forms six lobes  129  with indentations  131  formed between each of the lobes  129 . The knobs  180 ,  181  engage opposite lobes  129  to fix the rotational orientation of the hub  120  relative to the front housing  110 . 
         [0023]    Other mating shapes and configurations are also possible. The elongated cylindrical rear portion  123  of the hub  122  extends into the cavity  114  of the front housing  110 . 
         [0024]    The spring  130  surrounds the elongated cylindrical rear portion  123  of the hub  122 . The spring  130  is captured between the anti-rotation portion  128  and the rear housing  140 . The spring  130  functions to bias the anti-rotation portion  128  of the hub  122  into the anti-rotation seat  112  of the front housing  110 . Because the ferrule  124  is connected to the hub  122 , the spring  130  also functions to bias the ferrule  124  in a forward direction through the front bore  116 . 
         [0025]      FIGS. 2 and 3  show the final assembled positions of the front and rear housings  110  and  140 . An interference fit also is present when the front and rear housings  110  and  140  are partially inserted, as will be described below. The fiber optic cable  101  is extended through the front and rear housings  110  and  140  and is glued to the ferrule  124 . 
         [0026]    In example embodiments, the connector  100  is tunable. If tunable, the connector  100  can be tuned using various methods. For example, in one method, the connector  100  can be tuned by pushing the hub/ferrule assembly  120  backwards and rotating the hub/ferrule assembly  120  to a desired orientation when the connector  100  is in a partially assembled state. Details of such a tuning process can be found in U.S. Pat. No. 6,629,782, which is hereby incorporated by reference. In another example, the desired orientation can be determined after the connector  100  is assembled, and an outer key can be added to the connector  100  to indicate that orientation. Details of such a tuning process can be found in U.S. Pat. No. 5,212,752, which is hereby incorporated by reference. Other methods of tuning can also be used. 
         [0027]    Referring now to  FIGS. 5-8 , the hub/ferrule assembly  120  with a hub  122  and a ferrule  124  is shown. In this example, the hub/ferrule assembly  120 , including both the hub  122  and the ferrule  124 , is formed as a single piece. In other words, the hub/ferrule assembly  120  is a single, integrally molded piece. 
         [0028]    The hub/ferrule assembly  120  includes an internal passage  700  extending along the longitudinal axis  200  of the connector  100 . The internal passage  700  is sized to receive the terminal end of the fiber optic cable  101 , including a portion of the fiber  102  and the jacket  103 . 
         [0029]    An internal diameter  710  of the internal passage  700  is sized to receive the jacket  103  of the fiber optic cable  101 . In this example, the internal passage  700  includes a lead-in portion  704  that tapers to the diameter  710 , with the lead-in portion  704  allowing for the introduction of the jacket  103  into the internal passage  700 . In one example, the lead-in portion  704  has a maximum diameter of 0.060 inches, and the internal diameter  710  is 0.030 inches. Other dimensions and configurations are possible. 
         [0030]    The internal passage  700  narrows at a region  712  as the internal passage  700  extends towards the ferrule  124 . A diameter  714  of the internal passage  700  is sized to receive the fiber  102  of the fiber optic cable  101  extending therethrough. In this example, the diameter  714  is 0.0050 inches, although other dimensions can again be used. 
         [0031]    In some examples, the fiber  102  and/or the jacket  103  can be fixed within the internal passage  700  using various methods, such as by an adhesive. In other examples, one or both of the fiber  102  and the jacket  103  are retained within the passage  700  by a frictional fit. 
         [0032]    In example embodiments, the hub/ferrule assembly  120  is manufactured of a polymeric material using a molding process. In one example, the hub/ferrule assembly  120  is made of Polyphenylene Sulfide (PPS) using an injection molding process. Other materials and molding processes can be used. 
         [0033]    Several advantageous can be associated with an integral hub/ferrule assembly. One advantage is that the integral hub/ferrule assembly can be manufactured more efficiently, since steps requiring the hub to be connected to the ferrule are eliminated. Another advantage is that the integral hub/ferrule assembly can be more robust than other designs made out of multiple pieces. 
         [0034]    Although the examples shown herein illustrate an LC connector, other connector types can be used. For example, in alternative embodiments, an SC or LX.5 connector can be used, such as that illustrated in U.S. Pat. No. 6,629,782. 
         [0035]    Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.