Abstract:
In one embodiment, a bracket for attaching a Fiber Optic Coupler to a surface such as a printed circuit board. The bracket attaches to the surface using integrated latching fasteners and receives a coupler such as an SC-type coupler. Such a bracket may operate using no additional hardware, and may be constructed as a molding or may utilize subcomponents according to desired operating characteristics including flexibility, elasticity and friction.

Description:
BACKGROUND  
       [0001]     1. Field of the Invention  
         [0002]     Generally, the present invention relates to cable management. Specifically, this invention relates to fiber optic cable management.  
         [0003]     2. Description of Related Art  
         [0004]     Most telecommunications networks of today are based on active components at the serving office exchange and termination points at the customer premises as well as in the repeaters, relays and other devices in the transmission path between the exchange and the customer. In this context, active components are devices that require power of some sort, and generally comprise processors, memory chips and other devices that are active and processing information within and along the transmission path.  
         [0005]     In contrast, within a typical passive optical network (PON), passive optical components are used to guide traffic between the central office exchange and the customers&#39; premises based on splitting the power of optical wavelengths to endpoints along the way. This replacement of active components with passive components provides a cost-savings to service providers by eliminating the need to power and service active components in the transmission loop. The passive splitters or couplers merely pass or restrict light, and as such, have no power or processing requirements. For example, two subscription channel (“SC”) connectors may be coupled using an SC-type coupler, where an SC connector is a push-pull type of optical connector that features high packing density, low loss, low back-reflection, and low cost.  
         [0006]     In general, a typical PON consists of an optical line terminator (OLT), which is located at a central office (CO), and a set of associated optical network terminals (ONTs), which are located at customers&#39; premises. Between the OLT and the ONTs lies one or more optical distribution networks (ODNs), each ODN including fibers and one or more of passive splitters and passive couplers.  
         [0007]     Typically a multitude of parts (such as a sheet metal bracket, rivets, screws and lock washers) is used to fasten a fiber optic coupler to a printed circuit board (“PCB”) assembly. The multitude of parts in the assembly increases the time, expense and cost of labor required to install, remove or adjust the coupler. Additionally, the use of the rivets, screws and lock washers to secure the sheet metal bracket to the PCB assembly may crush the PCB locally and create short circuits within the buried traces of the PCB. Further, rework of a PCB with a coupler attached by rivets entails drilling out the rivets thereby creating a risk of further damage to the PCB, additional expense, and additional labor costs.  
         [0008]     What is needed is a fiber optic coupler that can be quickly and reliably installed on a PCB assembly with minimal mechanical force and few additional components.  
       SUMMARY  
       [0009]     In one embodiment, a bracket configured to secure a fiber optic coupler to a surface includes a base having a first side and a second side opposite to the first side. The bracket includes first and second side portions, said first and second side portions being provided on the first side of the base and being arranged to receive the coupler between them. The bracket includes first and second legs provided on the second side of the base and being configured to secure the bracket to the surface. In response to application of a lateral force to at least one of the first and second side portions, the bracket is deformable from a first configuration to a second configuration. In the first configuration, the first and second legs are positioned relative to one another to prevent removal of the bracket from the surface without damage to the bracket. In the second configuration, the first and second legs are positioned relative to one another to permit removal of the bracket from the surface without damage to the bracket. Presence of the coupler between the first and second side portions prevents deformation of the bracket from the first configuration to the second configuration in response to said application of lateral force.  
         [0010]     In another embodiment, a method for securing a fiber optic coupler to a surface using a bracket includes deforming the bracket from a first configuration to a second configuration and, while the bracket is in the second configuration, inserting at least one portion of the bracket into at least one corresponding hole in the surface. The method includes, subsequent to said inserting, allowing the bracket to return at least substantially to the first configuration such that said at least one portion is arranged to secure the bracket to the surface.  
         [0011]     In another embodiment, a bracket for securing a fiber optic coupler to a surface includes means for supporting the bracket, the means being deformable from a first configuration to a second configuration, and means for securing the bracket to the surface when the means for supporting is in the first configuration. The bracket includes means for inhibiting movement of the fiber optic coupler relative to the bracket when the means for supporting is in the first configuration. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     These and other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures, wherein:  
         [0013]      FIG. 1  is a mechanical drawing showing an exemplary embodiment of the invention;  
         [0014]      FIG. 2  is an assembly drawing illustrating the coupling of an exemplary bracket with an SC-type coupler.  
         [0015]      FIG. 3  shows a solder-side view of the legs of the exemplary bracket after attachment to a PCB.  
         [0016]      FIG. 4  shows a method of attaching the exemplary bracket to a PCB.  
         [0017]      FIG. 5  is an assembly drawing showing an embodiment of the invention as installed on an exemplary printed circuit board assembly. 
     
    
     DETAILED DESCRIPTION  
       [0018]     Embodiments of the present invention will now be described in detail with reference to the drawings, which are provided as illustrative examples so as to enable those skilled in the art to practice the invention. Notably, the figures and examples below are not meant to limit the scope of the present invention. Where certain elements of these embodiments can be partially or fully implemented using known components, only those portions of such known components that are necessary for an understanding of the present invention will be described, and detailed descriptions of other portions of such known components will be omitted so as not to obscure the invention. Further, the present invention encompasses present and future known equivalents to the components referred to herein by way of illustration.  
         [0019]     Referring to  FIGS. 1 and 2 , an exemplary embodiment of a fiber optic coupler mounting bracket  10  is shown. For the sake of clarity and for better illustration, an embodiment of the invention adapted to receive an SC-type coupler will be described. It will be appreciated, however, that various embodiments of the invention may receive coupler types including: SC-type for subscription channel connectors; LC-type, for precision physical contact, push-pull connectors; MU-type, for compact multiple optical connectors and couplers or adapters for connecting two or more dissimilar types of connectors; and/or other connector and/or coupler types in current or future use. It will be further appreciated, by one skilled in the art, that the geometry and dimensions of the bracket may be modified and customized according to the configuration of any selected coupler. For example, curved lines may be substituted for straight lines, inclined members may replace vertical members, and so on. Embodiments of the invention may also be adapted to attach connectors and connector assemblies to a surface.  
         [0020]     While the bracket  10  may be constructed as an assembly of a plurality of subcomponents, in at least some embodiments the bracket  10  is a single molded component. In other embodiments, the bracket or elements thereof may be stamped or cut from, e.g. a sheet of material. The bracket  10  may be fabricated from any one or more suitable materials including, for example, polycarbonate resin such as GE Lexan 923A, thermoplastic, thermoset resin, sheet metal, composite and molded rubber.  
         [0021]     In this exemplary embodiment, the bracket comprises a base  12 , a left side portion  14  and a right side portion  16 . The base  12  may be flat and generally rectangular with a front edge  120 , a back edge  121 , a left edge  122  and a right edge  123 . The base  12  may have a thickness selected according to the properties of the fabrication material to provide a desired flexibility and a desired elasticity such that the bracket  10  may be bendable to facilitate insertion on a PCB (or other surface or sheet-like material), as discussed below and shown in  FIG. 4 . In some embodiments, the base  12  may have a varying thickness e.g. so as to promote bending at a particular location and/or provide additional support or rigidity at another location.  
         [0022]     In this embodiment, the left side portion  14  rises vertically from the base  12  and is located on and along the front edge  120  of the base  12 , such that the left side portion  14  shares a corner with the front edge  120  and the left edge  122  of the base  12 . Similarly, the right side portion  16  rises vertically from the base  12  and is located on and along the front edge  120  of the base  12 , such that the right side portion  16  shares a corner with the front edge  120  and right edge  123  of the base  12 . In other embodiments, the base  12  may extend beyond the side portions  14 ,  16  in one or both directions. In further embodiments, the side portions  14 ,  16  may be oriented along the respective left and right edges  122 ,  123 .  
         [0023]     In this embodiment, a left supporting member  142  (not visible) connects a vertical edge of the left side portion  14  to the left side  122  of the base  12 , and a right supporting member  162  connects a vertical edge of the right side portion  16  to the right side  123  of the base  12 . The left supporting member  142  and the right supporting member  162  may be discrete linear or curved members or may be angular solid walls. In other embodiments, the left and right supporting members may extend from the surface of base  12  and/or the adjacent surface of the corresponding side portion  14 ,  16 , rather than connecting to an edge of the base and/or side portion. In further embodiments, the supporting members may be spaced to enclose a coupler intended to be seated therebetween.  
         [0024]     In this embodiment, the left side portion  14  and the right side portion  16  form two sides of a slot  18  in the front vertical plane of the bracket  10 , and the front edge  120  of the base  12  forms the third side of the slot  18 . In the exemplary embodiment, the slot  18  is configured to receive a coupler  20 . In some embodiments of the invention, an insert, washer or other intermediary may be used to seat the coupler  20 . Depending e.g. on the particular configuration of the coupler intended to be seated therein, other embodiments may include a front portion extending vertically from base  12  between the side portions  14 ,  16 .  
         [0025]     The dimensions of the slot  18  may be selected according to the dimensions of the coupler  20  (see  FIG. 2 ). In one exemplary embodiment where the bracket  10  attaches an SC-type coupler  20 , the slot has a nominal horizontal dimension (i.e. parallel to the front side  120 ) of 13.01 mm (0.512″) and a nominal vertical height of 10.41 mm (0.410″). It will be appreciated that the dimensions may be altered to permit the bracket  10  to receive other couplers, adapters and connectors of different sizes. It will be further appreciated that the dimensions of the slot  18  may be adjusted e.g. according to manufacturing and operational tolerances of the material(s) used to fabricate the bracket  10 .  
         [0026]     The base and/or one or both side portions  14 ,  16  may also include one or more indentations (e.g. holes) or protrusions configured to mate with corresponding features of the coupler. In the embodiment illustrated in  FIG. 1 , for example, a left locating pin  140  extends forward from the front of the left side portion  14 , and a right locating pin  160  extends forward from the front of the right side portion  16 , these pins being located to mate with corresponding holes in an SC-type coupler. In some embodiments, protrusions such as the right pin  160  and the left pin  140  may be constructed from or have a surface comprising a low friction material such as steel, aluminum, certain plastics, Teflon, composites, or rubber.  
         [0027]     A left leg  124  may be attached to the bottom of the base  12 , to the left of a center line  130  drawn from the front side  120  of the base to the back side of the base  12 , equidistant from the left side  122  and right side  123 . A right leg  126  may be attached to the bottom of the base  12 , to the right of the center line  130 . Both the left leg  124  and right leg  126  may have a post-like form  128  with a lip  129 , wherein the lip  129  is separated from the bottom surface of base  12  (e.g. by a thickness of a surface to which the bracket is intended to be attached).  
         [0028]     Referring now also to  FIGS. 3 and 4 , the dimensions of the lip  129  and the distance of the lip  129  from the base  12  are selected to allow the left leg  124  and right leg  126  to fasten the bracket  10  to a sheet-like material such as a PCB  30 . The bracket  10  may be attached to the PCB  30  by inserting the left leg  124  and right leg  126  into a left hole  32  and a right hole  34  of the PCB, respectively. The left hole  32  and the right hole  34  may have a diameter sufficient to allow a vertically oriented leg  124  and  126  to pass through the board without obstructing the lip  129 .  
         [0029]     The left leg  124  and the right leg  126  may be aligned such that the respective lips  129  are oriented toward the center line  130  thereby minimizing the distance between the lips  129 . Further, the posts  128  of the legs  123  and  124  may be inclined relative to the base  12  such that, when inserted into the holes  34  and  35 , the lips  129  extend beyond the perimeter of the holes  34  and  35  and overhang the PCB  30 . Thus, once attached, the bracket  10  may resist detachment due to force applied either incidentally or deliberately by, for example, pulling on a fiber cable  22  connected to a coupler  20  held by the bracket  10 .  
         [0030]     In some embodiments, the bracket  10  is attached and detached from the surface by bending the bracket  10  generally about the center line  130 . Such bending may increase the distance between the lips  129  of the legs and thus eliminate the overhang of the lip  129  with respect to the corresponding hole (see  FIG. 4 ). In the exemplary embodiment, bending the bracket  10  brings the left and right legs  123  and  124  into a parallel alignment, allowing the legs  123  and  124  to negotiate the holes  34  and  35  without obstruction.  
         [0031]     In some embodiments, a left opening  125  and a right opening  127  may be created on the base  12  adjacent to the left leg  124  and the right leg  126 , respectively, each opening extending in the direction of the center line  130 . The openings  125  and  127  may provide additional flexibility, allowing the legs  124  and  126  to be bent away from center line  130  for easy attachment and detachment of the bracket  10  with respect to the PCB  30 . The openings  125  and  127  may also facilitate using a tool (such as a screwdriver) to bend the legs  124  and  126 , thereby facilitating attachment or detachment of the bracket.  
         [0032]     Referring now to  FIGS. 1 and 2 , an application of the exemplary embodiment is illustrated. The bracket  10  receives the SC-type coupler  20 , wherein the type, form, dimensions and composition of the SC-type coupler  20  are known to one skilled in the art. In turn, the SC-type coupler  20  may receive a first fiber cable  22 , and a second fiber cable  24  (not shown), thereby connecting the first cable  22  to the second cable  24 . The left locating pin  140  and the right locating pin  160  matingly couple to a left hole  200  (not shown) and a right hole  202 , respectively. The left hole  200  and the right hole  202  are located on a left flange  201  and a right flange  203  of the coupler, respectively. The dimensions of the pins  140  and  160  are selected such that, when coupled with the holes  200  and  202 , rotation, shear and skew of the SC coupler  20  relative to the bracket  10  may be resisted.  
         [0033]     A left retaining clip  204  (not shown) located on a left side of the SC connector  20  engages with the left side portion  14 , and a right retaining clip  206  located on a right side of the SC connector  20  engages with the right side portion  16 . When engaged, the retaining clips prevent retraction of the SC-type coupler  20  from the bracket  10 . In other embodiments, one or both of the side portions  14 ,  16  may include a protrusion that retains the coupler to the bracket by engaging the top surface of the coupler.  
         [0034]     A potential advantage of at least some embodiments of the invention is a self-locking nature of the bracket  10 . In the exemplary embodiment, for example, once the SC-type coupler  20  is coupled to the bracket  10 , it may no longer be possible to bend the base  12  about the center line  130 . As a result, the bracket  10  may not be easily removed unless the SC-type coupler  20  is first retracted from the bracket  10 .  
         [0035]     Referring now to  FIG. 5  and for the purpose of illustration, a drawing of an exemplary bracket  10  is shown installed on a populated PCB  50 . An SC coupler  20  is shown attached to the bracket  10 . The left retaining clip  204  is shown engaged with the left side wall  14 . Further the first cable  22  is shown attached to the SC coupler  20 .  
         [0036]     At least some embodiments as described herein provide cost effective means to mount a Fiber Optic Coupler on a PCB. Embodiments of the present invention include a bracket that permits the attachment of a SC-type (“Subscription Channel”) coupler to a surface such as a PCB assembly without additional hardware components to secure the bracket. Embodiments of the invention also include a bracket that may be formed as a single molded piece. In some embodiments, the bracket may be constructed by combining components manufactured from various materials including sheet metal, composites, molded rubber, polycarbonate resin, thermoplastic, thermoset resin, steel, aluminum and Teflon. A bracket according to at least some embodiments may be easily installed to a PCB (for example), yet remain firmly attached while in use. A bracket according to at least some embodiments may be easily dismounted for maintenance, inspection and repair.  
         [0037]     It is apparent that the above embodiments may be altered in many ways without departing from the scope of the invention. For example and with reference to  FIGS. 1 and 3 , in some embodiments, the left leg  124  and the right leg  126  may be flexible and the base  12  may be rigid, such that attachment of the bracket  10  to the PCB  30  entails bending the legs  124  and  126  to pass the legs  124  and  126  through holes  32  and  34  in the PCB  30 . In another exemplary embodiment, the left leg  124 , the right leg  126  and the base  12  may be rigid, the legs  124  and  126  being connected to the base  12  in a hinged manner such that attachment to the PCB  30  entails bending the legs  124  and  126  to pass the legs  124  and  126  through holes  32  and  34  in the PCB  30 . Also, a variety of couplers may be secured using embodiments of the invention, including couplers that couple non-homogenous connectors including, for example, LC/SC couplers. Further, the invention may be expressed in various aspects of a particular embodiment without regard to other aspects of the same embodiment. Still further, various aspects of different embodiments can be combined together. Accordingly, the scope of the invention should be determined by the following claims and their legal equivalents.