Abstract:
A clip for securing a component, such as a circuit board, within a communications module is disclosed. The clip may include a flat base with legs extending therefrom and resilient springs disposed at terminal ends of each of the legs. The legs may be configured to frictionally secure the clip to the module. For instance, the legs may secure the clip to a top shell portion of the module. The springs may be configured to resiliently compress against corresponding contact zones on the circuit board when the top shell is mated with a bottom shell of the module such that the circuit board is secured in place within the module. Accordingly, embodiments of the invention enable the quick and simple assembly of modules without the need for fasteners and other time-consuming and/or labor-intensive solutions conventionally implemented to secure circuit boards and other components within the modules.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/949,163, entitled SPIDER CLIP FOR SECURING A CIRCUIT BOARD WITHIN A COMMUNICATIONS MODULE, filed Jul. 11, 2007, which application is herein incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. The Field of the Invention 
         [0003]    The present invention generally relates to communications modules. In particular, the present invention relates to an apparatus configured to secure a printed circuit board or other component(s) within an optical transceiver module or other communications module. 
         [0004]    2. The Related Technology 
         [0005]    Computing and networking technology has transformed our world. As the amount of information communicated over networks steadily increases, high speed transmission becomes ever more critical. Many high speed data transmission networks rely on communications modules, such as optical transceivers, transponders, and similar devices, for facilitating transmission and reception of digital data embodied in the form of optical signals over optical fibers. Optical networks are thus found in a wide variety of high speed applications ranging from modest Local Area Networks (“LANs”) to backbones that define a large portion of the infrastructure of the Internet. 
         [0006]    Typically, data transmission in such networks is implemented by way of an optical transmitter (also referred to as an “electro-optic transducer”), such as a laser or Light Emitting Diode (“LED”). The electro-optic transducer emits light when current is passed through it, the intensity of the emitted light being a function of the magnitude of the current. Data reception is generally implemented by way of an optical receiver (also referred to as an “opto-electronic transducer”), an example of which is a photodiode. The opto-electronic transducer receives light and generates a current, the magnitude of the generated current being a function of the intensity of the received light. 
         [0007]    Various other components are also employed by the optical transceiver to aid in the control of the optical transmit and receive components, as well as the processing of various data and other signals. For example, the optical transmitter is typically housed in a transmitter optical subassembly (“TOSA”), while the optical receiver is housed in a separate receiver optical subassembly (“ROSA”). The transceiver also typically includes a driver (e.g., referred to as a “laser driver” when used to drive a laser signal) configured to control the operation of the optical transmitter in response to various control inputs and an amplifier (e.g., often referred to as a “post-amplifier”) configured to amplify the channel-attenuated received signal prior to further processing. A controller circuit (hereinafter referred to as the “controller”) controls the operation of the laser driver and post-amplifier. The laser driver, post-amplifier, and controller are typically included on a printed circuit board (“PCB”) included within the transceiver. The TOSA and ROSA are operably connected to the printed circuit board so as to enable signals to pass between the TOSA/ROSA and the PCB-mounted components. 
         [0008]    An ever-present desire in the art relates to simplifying the assembly procedures for optical transceiver modules. For instance, the use of a screw or other fastener typically employed to secure the PCB to the interior of the transceiver housing can represent a relatively labor intensive procedure during transceiver assembly. As such, assembly of the transceiver can be undesirably delayed. 
         [0009]    In addition, a screw or other fastener used to secure the PCB typically passes through a central portion of the PCB so as to ensure a secure fixation of the PCB against the transceiver housing. The central region of the PCB, however, is a highly desirable location in terms of the desirability for the placement of various electronic components. In contrast, the perimeter portions of the PCB are not as highly utilized. 
         [0010]    A need therefore exists for an optical transceiver module including a printed circuit board having a simplified configuration that enables the printed circuit board to be secured within the transceiver quickly and simply so as to speed assembly time for the transceiver. Moreover, a need exists to maximize the usable surface area of prime portions of the printed circuit board. 
         [0011]    The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced. 
       BRIEF SUMMARY OF THE INVENTION 
       [0012]    These and other limitations are overcome by embodiments of the invention which relate to systems and methods for securing components within communications modules. More particularly, embodiments of the invention relate to a resilient clip for securing a printed circuit board or other component within a communications module, such as an optical transceiver module. Use of such a clip can simplify communications module design, hasten communications module assembly, and/or increase usable printed circuit board (“PCB”) space. 
         [0013]    An example resilient clip according to embodiments of the invention can include a base, two or more legs extending from the base that are configured to frictionally secure the clip to a communications module, and two or more springs-one each included at corresponding ends of the legs—that are configured to resiliently compress against corresponding contact zones on a circuit board disposed within the communications module when the communications module is assembled. To enable the resilient nature of the springs and/or other portions of the clip, the clip can contain metal, metal alloys, plastic, or the like or any combination thereof. The clip can further include two or more paired clips extending from the base in the opposite direction from the legs that can be implemented to further secure the clip to the communications module. Alternately or additionally, the clip can further include two or more extended portions to provide structural rigidity to the base and/or to disrupt EMI present in the communications module. 
         [0014]    A clip according to embodiments of the invention may be implemented in any of a variety of communications modules. For instance, the clip can be implemented in a transceiver module that includes a top shell portion and a bottom shell portion defining a cavity, and a circuit board disposed in the cavity. The legs of the clip can be configured to frictionally secure the clip to the top shell. In some cases, the legs of the clip can be configured to frictionally engage corresponding surfaces or features of the top shell to thereby secure the clip to the top shell. 
         [0015]    Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The features and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    To further clarify the above and other advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
           [0017]      FIG. 1  is a perspective view of an optical transceiver module including a spider clip for securing a printed circuit board (“PCB”) within the module interior, according to one example embodiment; 
           [0018]      FIG. 2  is a perspective end view of the transceiver of  FIG. 1 , showing various features of the spider clip and related securing features; 
           [0019]      FIGS. 3A-3C  include various views of the spider clip configured according to one embodiment; 
           [0020]      FIG. 4  is a perspective view of a top shell portion of the optical transceiver module of  FIG. 1 ; 
           [0021]      FIG. 5  is a perspective view of the top shell portion of  FIG. 4  having a spider clip affixed thereto; 
           [0022]      FIG. 6  is a cross-sectional view of the top shell portion of  FIG. 4  and spider clip attached thereto; 
           [0023]      FIG. 7  is a side view of the top shell portion of  FIG. 4  having the spider clip affixed thereto; 
           [0024]      FIG. 8  is a top view of the printed circuit board of  FIG. 2  showing contact zones for use with the spider clip of  FIGS. 3A-3C ; and 
           [0025]      FIG. 9  is a perspective view of a top shell portion and printed circuit board, showing the orientation of the spider clip with respect to the contact zones of the printed circuit board. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0026]    Reference will now be made to the figures wherein like structures will be provided with like reference designations. It is understood that the figures are diagrammatic and schematic representations of presently preferred embodiments of the invention, and are not limiting of the present invention, nor are they necessarily drawn to scale. 
         [0027]      FIGS. 1-9  depict various features of embodiments of the present invention, which is generally directed to a resilient clip for securing a component, such as a printed circuit board, within a communications module, such as an optical transceiver module. Use of such a clip simplifies transceiver design, hastens transceiver assembly, and increases usable PCB space. 
         [0028]    Reference is first made to  FIGS. 1 and 2 , which show a communications module, specifically, an optical transceiver module (“transceiver”), generally designated at  10 . Though having an SFP configuration, the transceiver  10  is merely representative of various communications modules and transceivers that can benefit from the principles of embodiments of the present invention as described herein. 
         [0029]    As shown in  FIG. 1 , the transceiver  10  includes a body comprising a top shell portion  12  and bottom shell portion  14 . The bottom shell portion  14  defines a front end  16  and a back end  17  of the transceiver  10 , while the top shell portion  12  defines a corresponding front end  16 A and back end  17 A. The top shell portion  12  also defines an inner surface  12 A that bounds the interior of the transceiver when assembled. 
         [0030]    Included on the front end  16  of the transceiver bottom shell portion  14  are two ports  18  configured to receive connectors of an optical fiber (not shown). The ports  18  define a portion of an interface portion  19  that is generally included on the front end  16  of the transceiver  10  and that includes the structures necessary to operably connect the transceiver  10  to optical fibers. Also disposed on the transceiver front end  16  is a bail latch assembly  50  that enables the transceiver to be selectively removed from a port, such as the port of a host device (not shown). 
         [0031]    As best seen in  FIG. 2 , the bottom shell portion  14  defines a cavity  20  in which a transmitter optical subassembly (“TOSA”)  22 , a receiver optical subassembly (“ROSA”)  24 , and printed circuit board (“PCB”)  26  are included as internal components of the transceiver  10 . The TOSA  22  and ROSA  24  each include a nosepiece  23  and  25 , respectively, that extends into a respective one of the ports  18  so as to be positioned to mate with the connector portion of an optical fiber (not shown) when received within each port. 
         [0032]    A terminal end of the PCB  26  nearest the back end  17  of the transceiver  10  includes an edge connector  28  that is configured to operably connect with a corresponding connector (not shown) of the host device. In addition, a hinge  52  ( FIG. 1 ) is defined on the back end  17 A of the top shell portion  12  and is configured to cooperatively engage with a hinge seat  54  defined near the back end  17  of the bottom shell portion  14  so as to enable the two shell portions to mate, thereby enclosing the cavity  20 . Of course, the transceiver or other communications module may include other types of mating configurations. 
         [0033]      FIGS. 1 and 2  further depict a clip, generally designated at  100 , that is attached to the top shell portion  12  and is configured to secure the PCB  26  in place within the cavity  20 , as is explained in further detail below. 
         [0034]    Note that, while described in some detail herein, the optical transceiver  10  is discussed by way of illustration only, and not by way of restricting the scope of the invention. For example, the optical transceiver  10  in one embodiment can be suitable for optical signal transmission and reception at a variety of per-second data rates, including but not limited to 1 Gigabit per second (“1 G”), 2 G, 4 G, 8 G, 10 G, or higher bandwidth fiber optic links. Also, the principles of the present invention can be implemented in optical transceivers of any form factor such as XFP, SFP, SFP+, IPF and SFF, without restriction. Furthermore, communications modules of other types and configurations, such as optical transponder modules, or having components that differ in some respects from those shown and described herein, can also benefit from the principles disclosed herein. 
         [0035]    During operation, the transceiver  10  can receive a data-carrying electrical signal from a host, which can be any computing system capable of communicating with the optical transceiver  100 , for transmission as a data-carrying optical signal onto an optical fiber (not shown). The electrical differential data signal is provided to a light source, such as a laser located in the TOSA  22 , which converts the electrical signal into a data-carrying optical signal for emission on to an optical fiber and transmission via an optical communications network, for instance. The laser (not shown) can be an edge-emitting laser diode, a vertical cavity surface emitting laser (“VCSEL”), a distributed feedback (“DFB”) laser, or other suitable light source. Accordingly, the TOSA  22  serves as an electro-optic transducer. 
         [0036]    In addition, the transceiver  10  can be configured to receive a data-carrying optical signal from an optical fiber (not shown) via the ROSA  24 . The ROSA  24  acts as an opto-electric transducer by transforming the received optical signal, via a photodetector or other suitable device included in the ROSA, into an electrical signal. The resulting electrical signal is then provided to the host device in which the transceiver  10  is received. 
         [0037]    Reference is now made to  FIGS. 3A-3C  in describing various details regarding the clip  100 , according to an example embodiment. As shown, the clip  100  may include a flat base  102  having integrally formed extended portions  104  extending therefrom in a downward direction, as viewed from the perspective depicted in  FIG. 3A . Two clips  106  may also extend downward from the base and may be configured for resiliently engaging portions of the top shell portion  12  in order to secure the clip onto the top shell portion, as will be described further below. The clips  106  may optionally be referred to herein as “paired clips” to distinguish them from the clip  100 , there being one clip  106  on each of opposite sides of the base  102 . 
         [0038]    Note that the extended portions  104  of the clip  100  can be designed to provide structural rigidity to the clip  100  between the paired clips  106 . In an example embodiment, the extended portions  104  can also be employed to disrupt electromagnetic interference (“EMI”) that may be present in the transceiver  10 . 
         [0039]    Four legs  108  extend from each of the four corners of the base in an arcing (e.g., “arc-wise”) upward direction as viewed from the perspective depicted in  FIG. 3A . A resilient spring portion  110  can be included at a terminal end of each leg  108 , interconnected thereto by an interconnecting portion  112 . Each spring portion  110  can be arc-shaped and resiliently formed to allow for a compressive force to be imposed on the PCB  26  when the transceiver  10  is assembled, as will be explained. Alternatively, the spring portions can define other shapes and configurations to enable resilient deformation thereof. To enable the spring portions  110  to be resilient, the clip  100  can contain: a metal or metal alloy, such as 301 or 302 stainless steel having a suitable one of a variety of spring hardness ratings; a plastic such as PA66, ABS; or the like or any combination thereof. 
         [0040]    Reference is now made to  FIG. 4 , which shows in detail the top shell portion  12 . The top shell portion  12  includes two side walls  120 , each having an inner surface  120 A. The side walls  120  each include a cutout  122  that is bounded by shoulders  124 . The described region of the top shell portion  12  serves as an example location of the clip  100  for use in securing the PCB  26  to the interior of the transceiver. Of course, modifications to either or both the clip and top shell portion can be made in other embodiments while still being encompassed by the claims of the present invention. 
         [0041]      FIGS. 5-7  depict in further detail the manner of attachment of the clip  100  to the top shell portion  12  of the transceiver  10 , in accordance with an example embodiment. As shown, the clip  100  can be placed such that edge portions of the clip base  102  are positioned against a portion of the side wall cutouts  122  and such that each leg  108  is positioned adjacent the correspondingly shaped portions of the cutouts. The interconnecting portion  112  of each leg  108  can frictionally engage the shoulder  124  of side wall cutouts  122 , thereby placing each spring portion  110  atop the corresponding side wall  120  proximate the respective cutout and holding the clip in place. As such, the legs  108  serve as one means for frictionally securing the clip  100  (and base  102 ) to the module  10 . The manner in which the legs  108  extend from the clip base  102  in the present example gives the clip a “spider”-like appearance, for which the clip  100  is also referred to herein as a “spider clip.” 
         [0042]    As best seen in  FIG. 6 , the clip  100  can alternately or additionally be secured in the position shown in  FIGS. 5-7  by engagement of the clips  106  with the inner surfaces  120 A. The clip engagement with the inner side wall surface  120 A can be a friction fit, which enables the clip  100  to be secured to the top shell portion  12  while also allowing for its simple removal from the transceiver  10 , when necessary. As such, the clips  106  serve as another means for frictionally securing the clip  100  (and base  102 ) to the module  10 . Note that other friction fit or securing schemes can be devised to secure the clip to the top shell portion, as may be appreciated by one skilled in the art with the benefit of the present disclosure. 
         [0043]    In light of the above, it is recognized that the clip structure illustrated in  FIG. 9  is formed so as to cooperatively fit with the shape of the top shell portion, specifically, the cutout portions  122 . Thus, it may be appreciated that the clip structure may be altered from what is explicitly shown so as to conform to attachment with a variety of shell shapes and/or transceiver structures. 
         [0044]      FIG. 8  shows a top view of the PCB  26  of  FIGS. 1 and 2  that can be disposed within the cavity  20  of the transceiver  10  ( FIG. 2 ). In accordance with embodiments of the invention, the top surface of the PCB  26  may include a plurality of zones  132  positioned at predetermined contact regions  130 . The contact regions  130  may correspond to points of contact of the clip  100  with the PCB  26  when the top shell portion  12  is mated with the bottom shell portion  14  as part of the transceiver assembly process. 
         [0045]      FIG. 9  shows the relative positional relationship between the zones  132  of the PCB  26  and the spring portions  110  when the PCB is disposed within the bottom shell portion (not shown). When the transceiver  10  is assembled, the clip  100  is attached to the corresponding portion of the top shell portion  12 , as has been depicted and described above. The top shell portion  12  can then be brought into a mated configuration with the bottom shell portion  14 , wherein the hinge  52  of the top shell portion engages the hinge seat  54  of the bottom shell portion. Mating of the two shell portions  12  and  14  causes the spring portions  110  of the clip  100  to come in contact with the zones  132  at the contact regions  130 . The tolerances of the clip  100  can be such that each spring portion  110  deforms slightly as it presses down on the PCB  26  as the two shell portions  12  and  14  are mated. This in turn provides a force on the PCB  26  to urge it into a secured position at the bottom of the PCB cavity  20 . As long as the transceiver shell portion  12  and  14  remain in a mated configuration, the clip  100  can ensure the PCB remains fixed in position within the transceiver  10 , as desired. 
         [0046]    Embodiments of the present invention may alternately or additionally provide for easy removal of the PCB  26  from the transceiver should such removal be necessary or desired. To remove the PCB  26 , the top and bottom shell portions  12  and  14  can be separated. Such separation can also remove the clip  100  from engagement with the PCB  26 . The PCB  26  is then easily removable from the transceiver  10 . Note that the number or position of the spring portions  110  included on the clip  100  can be varied to suit the particular securing or other needs for the PCB. 
         [0047]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.