Abstract:
A fiber optic industrial connector includes a connector holder and a duplex clip assembly secured within the connector holder. The duplex clip assembly includes a duplex clip and two connectors secured within the duplex clip. The duplex clip has a front surface and a rear surface, and two openings positioned between the front surface and the rear surface. The duplex clip also has a projecting member extending from the rear surface and toward the front surface.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
   This application claims priority to U.S. Provisional Application Ser. No. 60/622,636, filed on Oct. 27, 2004, the entirety of which is incorporated herein by reference. 

   BACKGROUND OF THE INVENTION  
   The present invention is directed to a fiber optic industrial connector and, more particularly, an LC fiber optic industrial connector. 
   Industrial telecommunication connectors are known in the art, as shown and described in U.S. Pat. Nos. 6,475,009 and 6,595,791. The &#39;009 and &#39;791 patents disclose RJ-45 connectors, which do not include duplex clip and connector assemblies. Moreover, none of these prior art industrial connectors disclose an LC fiber optic industrial connector that allows simple removal of the LC connectors during or after termination. 
   SUMMARY OF THE INVENTION  
   It would be desirable to provide an LC fiber optic industrial connector that allows simple removal of the LC connectors during or after termination. 
   It would also be desirable to provide an LC fiber optic industrial connector having an LC duplex clip and two LC connectors removably secured to an LC connector holder. 
   A fiber optic industrial connector includes a connector holder and a duplex clip assembly secured within the connector holder. The duplex clip assembly includes a duplex clip and two connectors secured within the duplex clip. The duplex clip has a front surface and a rear surface, and two openings positioned between the front surface and the rear surface. The duplex clip also has a projecting member extending from the rear surface and toward the front surface. 
   Preferably, the connector holder has a retaining wall along an inside surface thereof. 
   Preferably, each duplex clip opening is substantially C-shaped and has a latch on an inside surface thereof. 
   Preferably, the projecting member is a cantilevered beam and includes a latch positioned thereon. 
   Preferably, the fiber optic industrial connector is an LC style connector. 

   
     BRIEF DESCRIPTION OF THE FIGURES  
       FIG. 1  is a rear perspective view of an assembled industrial connector according to the present invention; 
       FIG. 2  is a front perspective view of the industrial connector of  FIG. 1 ; 
       FIG. 3  is an exploded perspective view of the industrial connector of  FIG. 2 ; 
       FIG. 4  is a front perspective view of a duplex clip shown in  FIG. 3 ; 
       FIG. 5  is a front view of the duplex clip shown in  FIG. 3 ; 
       FIG. 6  is a right side view of the duplex clip shown in  FIG. 3 ; 
       FIG. 7  is a front perspective view of an LC connector shown in  FIG. 3 ; 
       FIG. 8  is a partial exploded perspective view of a plug assembly for the industrial connector of  FIG. 2 ; 
       FIG. 9  is a top view of the two LC connectors and LC duplex clip shown in  FIG. 8 ; 
       FIG. 10  is a cross-sectional view taken along lines  10 — 10  of  FIG. 9 ; 
       FIG. 11  is an enlarged perspective view of the plug assembly of  FIG. 8 , showing the LC connectors secured within the LC duplex clip; 
       FIG. 12  is a top view of the LC connectors and LC duplex clip shown in  FIG. 11 ; 
       FIG. 13  is a cross-sectional view taken along lines  13 — 13  of  FIG. 12 ; 
       FIG. 14  is a cross-sectional view taken along lines  14 — 14  of  FIG. 12 ; 
       FIG. 15  is a partial exploded top view of the industrial connector of  FIG. 2 ; 
       FIG. 16  is a cross-sectional view taken along lines  16 — 16  of  FIG. 15 ; 
       FIG. 17  is an enlarged cross-sectional view of the plug assembly shown in  FIG. 16 ; 
       FIG. 18  is an enlarged cross-sectional view of the plug assembly shown in  FIG. 16 , showing the LC duplex clip being inserted into the LC connector holder; 
       FIG. 19  is an enlarged cross-sectional view of the plug assembly shown in  FIG. 16 , showing the LC duplex clip after being inserted into the LC connector holder; 
       FIG. 20  is a partial exploded perspective view of the industrial connector of  FIG. 2 ; 
       FIG. 21  is a partial exploded perspective view of the industrial connector of  FIG. 2 ; 
       FIG. 22  is a partial exploded perspective view of the industrial connector of  FIG. 2 ; 
       FIG. 23  is a side view of the industrial connector of  FIG. 2 ; 
       FIG. 24  is a cross-sectional view taken along lines  24 — 24  of  FIG. 23 ; 
       FIG. 25  is a top view of the industrial connector of  FIG. 2 ; 
       FIG. 26  is a cross-sectional view taken along lines  26 — 26  of  FIG. 25 ; 
       FIG. 27  is a cross-sectional view taken along lines  27 — 27  of  FIG. 25 ; 
       FIG. 28  is a perspective view of the plug assembly for the industrial connector of  FIG. 2 ; 
       FIG. 29  is a perspective view of the plug assembly for the industrial connector of  FIG. 2 , showing the plug cap secured to the plug collar; 
       FIG. 30  is a perspective view of the bulkhead assembly for the industrial connector of  FIG. 2 ; and 
       FIG. 31  is a perspective view of the bulkhead assembly for the industrial connector of  FIG. 2 , showing the bulkhead cap secured to the bulkhead. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
     FIGS. 1–31  illustrate an LC fiber optic industrial connector  40 . It is likewise contemplated that other fiber optic style connectors, such as an SC or an ST style connector, may be utilized.  FIG. 3  shows an exploded view of the components of industrial connector  40 .  FIGS. 28 and 29  show an assembled plug-side  42  of industrial connector  40 , and  FIGS. 30 and 31  show an assembled bulkhead-side  44  of industrial connector  40 . 
   Referring to  FIG. 3 , in order to assemble plug-side  42  of industrial connector  40 , plug sealing gasket  46  and O-ring  48  are first installed onto the front and rear sides of LC connector holder  50 , respectively, creating an LC connector holder assembly. Plug face seal  54  and plug tether  56  are then installed onto plug cap  58 , creating a plug cap assembly. Flexible boot  62 , liquid-tight fitting  64  and the plug cap assembly are slid onto fiber cable  66 . Plug collar  60 , the LC connector holder assembly and crimp sleeves  68  are subsequently slid onto fiber cable  66 . The fibers are then terminated onto two LC connectors  70  using standard termination procedures. 
   The two terminated LC connectors  70  are then slid into the sides of LC duplex clip  72  and secured by LC duplex clip latches  74  (see  FIG. 5 ), which snap into recesses on LC connectors  70  (see  FIG. 13 ). This assembly is then installed into the opening at the front of LC connector holder  50 . Once seated completely inside LC connector holder  50 , LC connector latches  76  become depressed and therefore inoperable (see  FIG. 19 ). 
   Finally, plug collar  60  and the plug cap assembly are slid over the rear of the LC connector holder assembly and secured by threading liquid-tight fitting  64  into LC connector holder  50 . Flexible boot  62  is threaded onto liquid-tight fitting  64 . Once flexible boot  62  is fully secured, liquid-tight fitting  64  compresses onto the round fiber cable  66 , creating a sealed cable/plug interface. Optionally, and as shown in  FIG. 29 , plug cap  58  may be secured to plug collar  60 . 
   Referring to  FIG. 3 , in order to assemble the bulkhead-side  44  of industrial connector  40 , bulkhead face seal  78  is assembled onto the front of bulkhead  80 . Bulkhead-sealing gasket tether  82  and a plug sealing gasket (not shown) are assembled onto bulkhead cap  84 , and this assembly is then slid over the threads at the rear of bulkhead  80 . Alternatively, bulkhead-sealing gasket  86  is slid over the threads at the rear of bulkhead  80 . 
   Duplex LC adapter module  88  including a duplex LC adapter  90  is snapped into the rear of bulkhead  80  and retained in place by integrated bulkhead latch  92 . The sub-assembly is then positioned through the hole in mounting panel  94 , in any of four 90 degree orientations. Bulkhead  80  can be rotated in 90 degree intervals before assembly nut  96  is secured. Thrust washer  98  is aligned over the threads at the rear of bulkhead  80 , and assembly nut  96  is threaded onto bulkhead  80 , securing the entire bulkhead assembly. Optionally, and as shown in  FIG. 31 , bulkhead cap  84  may be secured to bulkhead  80 . 
   Referring to  FIG. 3 , in order to mate plug-side  42  and bulkhead-side  44  of industrial connector  40 , LC connectors  70  are inserted into the opening in bulkhead  80 . The keyway from LC connector holder  50  accurately aligns the LC industrial connector plug to bulkhead  80 . Plug collar  60  is rotated into place and secured by pins  100  on plug collar  60  which mount into grooves  102  on bulkhead  80  (see  FIGS. 21 and 22 ). The pin and groove mounting arrangement prohibits the mated components from separating. 
   The internal components of industrial connector  40  are secured in different ways than a typical copper or fiber industrial connector. The plug-side of a typical industrial connector is held together at only one location, the cable. When the flexible boot is threaded onto the liquid-tight fitting, the liquid-tight fitting compresses onto the cable, which creates the only locking mechanism within a typical industrial connector. It may be possible to use this mechanism on a standard copper-based industrial connector because the copper connector housing is crimped very tightly onto the cable. This allows the connector from the plug-side of a typical copper-based industrial connector to be a clearance fit into a hole in its connector holder. However, the copper connector housing is not secured to the connector holder. 
   Attaching the liquid-tight fitting solely to a fiber cable will not always provide a robust LC industrial connector. If a fiber connector were to loosen from the outer PVC jacket of a fiber cable at the crimp area, this could allow the LC connectors to move forward in the plug holder. However, the present invention provides the additional support means necessary for industrial connector  40  to function in a robust fashion. 
   As shown in  FIGS. 10–13 , LC connectors  70  are assembled into the sides of LC duplex clip  72 . The duplex clip/connector assembly is then slid into the front opening of LC connector holder  50 , as best seen in  FIGS. 17 and 18 . The LC duplex clip/connector assembly becomes fully seated inside LC connector holder  50  once the LC connector housings bottom out inside LC connector holder  50 . At this point, LC duplex clip latch  104  engages inside LC connector holder  50 , creating an audible click. As shown in  FIG. 19 , latch  104  prevents LC connectors  70  from falling out of the front of LC connector holder  50  during removal of the LC industrial connector plug from bulkhead  80 . 
   The present duplex clip design also solves the problem with conventional industrial connectors in general. The final assembly task for the plug-side of a typical industrial connector requires tightening of the nut from the flexible boot onto a liquid-tight fitting. Tightening this nut with substantial torque shifts the cable inside the connector holder forward. In a conventional industrial connector, this forces the plug to shift forward in the connector holder, because the only gripping force on the cable is at the cable strain relief. 
   However, in the present invention, when the nut from flexible boot  62  is secured onto liquid-tight fitting  64 , LC connectors  70  will not move forward because duplex clip latch  104  catches onto retaining wall  106  at the front of LC connector holder  50 , as shown in  FIGS. 19 and 26 . This retaining feature secures LC connectors  70  more precisely in the axial direction. When plug-side  42  of industrial connector  40  is mated with another LC connector  70  at the far side of LC adapter  90 , this will position the plug-side ferrule endface with more precision. This, in turn, will ensure a tighter range of spring forces in LC connectors  70 , which will ultimately provide more reliable optical measurements. 
   Additionally, LC connectors  70  can be removed at any time from the front of LC connector holder  50 . First, flexible boot  62  is loosened to release the compression force on cable  66 . Next, cantilevered beam  108  at the front of LC duplex clip  72  is deflected downward with a finger or screwdriver, which disengages LC duplex clip latch  104  from retaining wall  106  found on LC connector holder  50 . Thus, LC connectors  70  are allowed to be pulled forward. Releasing LC connectors  70  from LC connector holder  50  will allow the ferrule endfaces to be repolished or inspected with a magnification scope at any time after connector termination, if necessary. 
   The disclosed invention provides an LC fiber optic industrial connector that allows simple removal of the LC connectors during or after termination. It should be noted that the above-described and illustrated embodiments and preferred embodiments of the invention are not an exhaustive list of the forms such an LC fiber optic industrial connector in accordance with the invention might take; rather, they serve as exemplary and illustrative of embodiments of the invention as presently understood. Many other forms of the invention are believed to exist.