Abstract:
A fiber optic connector module is provided for assembly at a rear face of a fiber optic connector assembly. The module includes a ferrule terminated to at least one optical fiber. A housing is spaced behind the ferrule and includes a rear end exposed at said rear face of the connector assembly. An extender member is removably attached to the housing at the rear end thereof and extends away from the rear face of the connector assembly for facilitating manipulation of the connector module.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention generally relates to the art of fiber otic connectors and, particularly, to a self-contained fiber optic connector module which has an extender to facilitate assembly and removal of the module from a connector housing, an adapter or the like.  
       BACKGROUND OF THE INVENTION  
       [0002]     Fiber optic connectors of a wide variety of designs have been employed to terminate optical fiber cables and to facilitate connection of the cables to other cables or other optical fiber transmission devices. A typical fiber optic connector includes a ferrule which mounts and centers an optical fiber or fibers within the connector. The ferrule may be fabricated of such material as ceramic. A ferrule holder or other housing component of the connector embraces the ferrule and may be fabricated of such material as molded plastic. A spring may be disposed within the housing or ferrule holder such that the ferrule is yieldably biased forwardly for engaging another fiber-mounting ferrule of a mating connecting device.  
         [0003]     A pair of fiber optic connectors or a connector and another optical fiber transmission device often are mated in an adapter which centers the fibers to provide low insertion losses. The adapter couples the connectors together so that their encapsulated fibers connect end-to-end. The adapter may be an in-line component, or the adapter can be designed for mounting in an opening in a panel, backplane, circuit board or the like.  
         [0004]     Various problems continue to be encountered in designing fiber optic connector assemblies or other connector assemblies, including applications involving backplanes, motherboards, daughterboards and the like. For instance, a plurality of fiber optic connector modules which are terminated to a respective plurality of fiber optic cables or ribbons often are assembled into the rear of a connector housing, adapter, or the like. The modules have ferrules at the front ends thereof which terminate the individual fibers of the fiber optic cables, with mating faces of the ferrules being exposed at the front end of a connector housing, adapter or the like. Problems continue to be encountered in assembling the modules by an operator. Particularly, it is difficult to manually manipulate the modules into their respective positions at the back end of the connector housing or an adapter. The delicate fiber optic cables often are damaged during such assembly operations. The present invention is directed to solving these problems by providing an extender system which makes it easier to assemble such fiber optic connector modules without damaging the terminated fiber optic cables or ribbons.  
       SUMMARY OF THE INVENTION  
       [0005]     An object, therefore, of the invention is to provide a fiber optic connector module with a new and improved extender member.  
         [0006]     In the exemplary embodiment of the invention, a fiber optic connector module is provided for assembly at a rear face of a fiber optic connector assembly. The module includes a ferrule terminated to at least one optical fiber. The ferrule includes a front mating end and a rear end. A pin keeper is engaged with the rear end of the ferrule. At least one alignment pin extends from the pin keeper through the ferrule and projects beyond the front mating end of the ferrule. A housing or pusher member is spaced behind the pin keeper and includes a rear end exposed at the rear face of the connector assembly. A spring is sandwiched between the housing or pusher member and the pin keeper. An extender member is attached to the pusher member at the rear end thereof and extends away from the rear face of the connector assembly for facilitating manual manipulation of the connector module.  
         [0007]     As disclosed herein, the housing or pusher member is generally hollow and has an open rear end through which the optical fiber extends. The extender member is attached to the pusher member within the open rear end thereof. According to one aspect of the invention, the extender member includes at least one attachment arm inserted into the open rear end of the pusher member. Complementary interengaging latch means, such as a latch boss on the attachment arm, is interengageable with a latch shoulder on the pusher member within the open rear end thereof to hold the extender member at the rear of the pusher member. In the preferred embodiment, a pair of the attachment arms are spaced laterally of each other on opposite sides of the optical fiber. The attachment arms have guide rails insertable into respective guide grooves at opposite sides of the hollow pusher member to prevent the attachment arms from inwardly moving toward the optical fiber.  
         [0008]     According to another aspect of the invention, the extender member includes a longitudinal slot through a side thereof and through which the optical fiber can pass in a direction transversely of the fiber. Therefore, the extender member can be assembled and attached to the pusher member after the optical fiber is terminated in the fiber optic connector module.  
         [0009]     Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the figures and in which:  
         [0011]      FIG. 1  is a perspective view of a mating connector assembly embodying the concepts of the invention, with the assembly in unmated condition;  
         [0012]      FIG. 2  is a perspective view of the mating connector assembly in mated condition;  
         [0013]      FIG. 3  is a view similar to that of  FIG. 2 , but taken at a different angle relative thereto, to show a plurality of the extender members of the invention, with one of the extender members removed from its respective fiber optic connector module to facilitate the illustration;  
         [0014]      FIG. 4  is a rear perspective view of one of the fiber optic connector modules with an extender member attached thereto;  
         [0015]      FIG. 5  is a view similar to that of  FIG. 4 , with the extender member removed or in the process of being attached to the module;  
         [0016]      FIGS. 6A and 6B  are perspective views taken at different angles to show the rear open end of the pusher member of the connector module; and  
         [0017]      FIGS. 7A-7C  are perspective views taken at different angles of the extender member. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0018]     Referring to the drawings in greater detail, and first to  FIGS. 1-3 , the invention is illustrated for use in a mating connector assembly, generally designated  10 , which includes a backplane connector assembly, generally designated  12 , mateable with a daughterboard connector assembly, generally designated  14 . The backplane connector assembly is mounted in an aperture  16  in a substrate  18 , panel or backplane which, in the illustrated embodiment, is a printed circuit board. Specifically, backplane  18  can be considered the “motherboard” herein. The daughterboard connector assembly is mounted on a top surface of a second printed circuit board  20  which is considered the “daughterboard” herein.  
         [0019]     Backplane connector assembly  12  includes an adapter, generally designated  22 , which is mounted in aperture  16  in motherboard  18 . Four fiber optic connector modules, generally designated  24 , are inserted into adapter  2 , through aperture  16 , from the front of backplane  18 . Each fiber optic connector module is terminated to a multi-fiber cable  26 . Each cable is a flat or “ribbon” cable having a plurality of optical fibers.  
         [0020]     After daughterboard connector assembly  14  is mounted on daughterboard  20 , four fiber optic connector modules, generally designated  28 , or inserted into the back of a connector housing  30  which has a rear face  30   a . Each module  28  is terminated to a flat, multi-fiber cable  32  similar to fiber optic cables  26 . Backplane connector  12  and daughterboard connector assembly  14  are mateable in the direction of arrows “A” ( FIG. 1 ) to a mated condition shown in  FIGS. 2 and 3 , wherein the fibers of cables  26  and  32  are functionally connected. Other details of mating connector assembly  10  such as the latches between adapter  22  and connector housing  30 , etc. can be derived from copending patent application Ser. No. 09/455,621 which was filed Dec. 7, 1999, and which is incorporated herein by reference.  
         [0021]      FIG. 3  shows a plurality of extender members (“extenders”), generally designated  36 , which are inserted into the rear ends of fiber optic connector modules  28 . One of the extenders  36  is shown in  FIG. 3  removed from its respective module to show how one of the modules appears at the rear of connector housing  30  of daughterboard connector assembly  14 . It can be seen how fiber optic cables  32  project out of the rear ends of modules  28 . Heretofore, when the modules have been manipulated and inserted into the rear of connector housing  30 , problems have been encountered in damaging fiber cables  32  because of the small sizes of the modules and cables as well as the close arrangement of the modules in the connector housing, leaving little space therebetween. Consequently, extenders  36  have been developed to facilitate manipulation of the modules without damaging the cables. In fact, as will be seen hereinafter, the modules can be used with or without the extenders even after cables  32  are terminated in the modules, because in some applications the extenders may not be desirable because they lengthen the overall dimensions of daughterboard connector assembly  28 .  
         [0022]     At this point, it should be understood that the concepts of the invention incorporated in extenders  36  and their interconnection with modules  28  are not limited to an application such as with the specific mating connector assembly  10  or backplane connector assembly  12  or daughterboard connector assembly  14 . The invention is equally applicable with a wide range of fiber optic connector assemblies or other connector assemblies wherein difficulties are incurred in assembling connector modules into connector housings, adapters or the like.  
         [0023]     With those understandings,  FIGS. 4 and 5  show one of the fiber optic connector modules  28 , along with a respective one of the extenders  36 . Specifically, each module  28  includes a ferrule  38  for terminating multi-fiber cable  32 , the ferrule having a front mating face or end  38   a  and a rear end  38   b . The ferrule includes a pair of through holes or passages (not visible in the drawings) for receiving a pair of alignment pins  40  fixed to a pin keeper  42  which abuts against the rear of ferrule  38  so that the distal ends of alignment pins  40  project forwardly of front mating face  38   a  of ferrule  38 . A coil spring  44  is fixed to a rear end of pin keeper  42 , and a housing or spring pusher member  46  is fixed to the rear end of the coil spring. Both pin keeper  42  and pusher member  46  may be fabricated of molded plastic material. An integral, flexible latch arm  48  projects outwardly from the pusher member for latching the fiber optic connector module within the rear of connector housing  30  of daughterboard connector assembly  14 , as can be seen in  FIG. 3 . Other details of fiber optic connector module  28  can be derived from the aforementioned pending patent application. Suffice it to say, both pin keeper  42  and the housing or pusher member  46  are generally hollow so that fiber optic cable or ribbon  32  can extend completely therethrough for termination of the individual fibers of the cable within ferrule  38 .  
         [0024]      FIG. 4  shows extender  36  attached to the rear of pusher member  46 , while  FIG. 5  shows the extender member removed or about to be attached to the pusher member. As stated above, some connector assembly applications may require the extender while other applications may omit the extender, and the extender is fabricated to allow for its use or nonuse even after fiber optic cable  32  is terminated in fiber optic connector module  28 .  
         [0025]      FIGS. 6A and 6B  show one of the pusher members  46  of one of the fiber optic connector modules  28  ( FIGS. 4 and 5 ). The pusher member has a rectangular open rear end  50  through which the fiber optic cable extends and into which extender  36  is mounted. A pair of latch windows  52  ( FIG. 6B ) are formed in opposite side walls of the pusher member slightly inwardly from the open rear end thereof. The forward edges of these windows form latch shoulders for purposes described hereinafter. The opposite edges of open rear end  50  are provided with chamfered or angled lead-in surfaces  54  immediately to the rear of latch windows  52 . As best seen in  FIG. 6A , four guide grooves  56  are formed in the four corners of rectangular open end  50  and extend inwardly of the hollow pusher member, again, for purposes described hereinafter.  
         [0026]      FIGS. 7A-7C  show details of one of the extenders  36 . Each extender includes a body  56  having a rectangular through passage  58  through which fiber optic cable  32  can pass. A pair of attachment arms  60  project forwardly of body  56 . The attachment arms are elongated and blade-like and include thin guide rails  62  formed along the outside of the top and bottom edges of the arms. A latch boss  64  projects outwardly from each attachment arm  60 . Each latch boss has a forward chamfered surface  64   a . A longitudinal slot  66  extends the entire length of body  56  and communicates with interior passage  58 . As best seen in  FIGS. 7B and 7C , attachment arms  60  are spaced laterally of the extender and, in assembly, are spaced on opposite sides of fiber optic cable  32  which will extend through the extender. Longitudinal slot  66  is in line with the gap between the attachment arms, whereby the extender can be completely assembled even after the fiber optic cable is terminated within module  28 , as will be seen hereinafter.  
         [0027]     In comparing  FIGS. 7A-7C  with  FIGS. 6A-6B , it can be seen that guide rails  62  at opposite edges of attachment arms  60  will move into guide grooves  56  at the four corners of rectangular open end  50  of pusher member  46 . When extender  36  is pushed all the way to its fully assembled position, a shoulder  70  ( FIGS. 7A-7C ) at the front of body  56  of the extender will abut against a rear face  72  of the pusher member. During assembly, chamfered surfaces  64   a  of latch bosses  64  will engage chamfered surface  54  at the entrance to open rear end  50  of the pusher member. With the extender and the pusher member being fabricated of such material as molded plastic or the like, latch bosses  64  of the extender will snap into latching engagement with latch windows  52  of the pusher member to hold the extender in completely assembled position.  
         [0028]     Finally, referring back to  FIG. 5 , as stated above, extender  36  can be assembled to pusher member  46  after fiber optic cable  32  is completely terminated within fiber optic connector module  28 . Specifically, longitudinal slot  66  in body  56  and the gap between attachment arms  60  are aligned with fiber optic cable  32 , and extender  36  is moved in the direction of arrow “B” ( FIG. 5 ) so that the cable passes through slot  66  and the gap between the attachment arms, until the cable extends the entire length of the extender within interior passage  58 . The extender then is moved forwardly in the direction of arrow “C”, inserting attachment arms  60  into open rear end  50  of pusher member  46 . As stated above, guide rails  62  at opposite edges of the attachment arms will ride in guide grooves  54  within the hollow pusher member. When front face  70  of body  56  of the extender abuts against rear face  72  of the pusher member, the extender will be fully assembled with latch bosses  64  snapping into latching engagement within latch windows  52 .  
         [0029]     It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.