Abstract:
Apparatus and methods are provided for securing a component such as a printed circuit board in a device at a single edge of the component, thereby facilitating removal and replacement, increasing unobstructed access for attachments and cabling, and improving potential density capacity of the components within a device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/111,459, filed Feb. 3, 2015, which is incorporated by reference herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to an apparatus for holding and securing a printed circuit board (PCB) or other electronic component at a single edge, such that the remaining edges of the PCB are accessible for attachment to cabling or other devices and permitting dense packing of PCB&#39;s. 
     BACKGROUND 
     A printed circuit board (“PCB”) contains embedded components for electrical circuits, connected by conductive tracks and other features that are etched from a conductive material, such as a copper sheet, that is laminated onto a non-conductive substrate. PCB&#39;s are incorporated into virtually all electronic products, computers, servers, etc. 
     A PCB must be secured to an enclosure in a device into which it is incorporated. Standoffs are often used to secure a PCB to an enclosure if it is not necessary to remove the PCB often and changeable components are easily accessible. However, this method makes it difficult to provide unobstructed access to the PCB to facilitate installation or assembly or for later removal, particularly after additional components are installed near the PCB. 
     Another standard way to secure a PCB is to use slots, which provide a channel on two ends for the PCB to slide into the enclosure such that it can easily be removed and replaced for repairs and upgrades. However, such an arrangement leaves only one edge of the PCB available for attachment of additional components such as cabling. 
     There is a need for an improved mounting mechanism for PCB&#39;s that facilitates installation and removal and which provides unobstructed access for attachments and cables. 
     BRIEF SUMMARY OF THE INVENTION 
     Apparatus and methods are provided for securing components, such as PCBs, in electronic devices. 
     In one aspect, an apparatus is provided, comprising: (a) a field replaceable unit (FRU), comprising: (i) a component that comprises a front face and a backing face that is opposed to the front face, and a bottom edge; (ii) a backer plate that comprises a first face, a second face opposed to the first face, and a bottom edge, and (ii) at least two bottom spacers attached in proximity to the bottom edges of the component and the backer plate, and configured to hold the bottom edges in a substantially parallel configuration relative to one another with space therebetween such that the backing face of the component faces the first face of the backer plate; and (b) a base plate, wherein the base plate comprises recessed pockets each with a recessed upper surface and a saddle between the pockets with a raised upper surface and parallel walls, wherein the saddle comprises a width and a height relative to the recessed upper surfaces of the pockets such that bottom edges of the component and the backer plate straddle the saddle and are secured in the apparatus. 
     In another aspect, a method is provided, comprising: securing a FRU in a base plate, wherein the FRU comprises (i) a component that comprises a front face and a backing face that is opposed to the front face, and a bottom edge; (ii) a backer plate that comprises a first face, a second face opposed to the first face, and a bottom edge, and (ii) at least two bottom spacers attached in proximity to the bottom edges of the component and the backer plate, and configured to hold the bottom edges in a substantially parallel configuration relative to one another with space therebetween such that the backing face of the component faces the first face of the backer plate, wherein the base plate comprises recessed pockets each with a recessed upper surface and a saddle between the pockets with a raised upper surface and parallel walls, wherein the saddle comprises a width and a height relative to the recessed upper surfaces of the pockets such that bottom edges of the component and the backer plate straddle the saddle and are secured in the apparatus, and wherein the method comprises inserting the FRU such that the backing face of the component and the first face of the backer plate straddle the saddle at their bottom edges, thereby securing the component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view from above of all components embodying the invention before the PCB is secured. 
         FIG. 2  is the same components shown in  FIG. 1  after the PCB has been secured. 
         FIG. 3  is a plan view from directly above all components. 
     
    
    
     DETAILED DESCRIPTION 
     The invention provides an apparatus for securing a component such as a PCB. This invention provides a way to secure a PCB or other component such that it can easily be removed and replaced but holds the component from one edge only, which may give the following advantages, including, but not limited to:
         Maximizes options and space for cabling to the PCB as all edges are accessible except one.   Minimizes area needed as a plurality of PCBs can be more densely packed.   Simple to create with minimal components.   Provides clearance by design for solder joints and other protrusions which may be on the rear of the PCB.       

     The components of an embodiment of the apparatus are shown in  FIG. 1 :
         A Field Replaceable Unit (termed “FRU” herein)  10  is created by attaching a PCB  11  to a Backer Plate  12 . The PCB may be connected to the Backer Plate, for example, using common Standoffs  13 .   A Base Plate  20  is created by cutting an array of “pockets”  21  with a given Pocket Corner Radius  22  into plate material. The coincidence of these pockets defines a raised area  23  therebetween, relative to the top surface of the adjacent pockets (termed “Saddle” herein).       

     The FRU  10  components may be of any dimensions that are suitable for the device into which the FRU will be incorporated, e.g., hand-held electronic device, computer, server, etc. In one embodiment, the FRU is sized to accommodate a mini-ITX format mother board, e.g., with PCB and backer plate faces 7 inch×7 inch. 
     In the assembled FRU, at least one edge of the PCB is parallel or substantially parallel to at least one edge of the backer plate when connected with standoffs or separator hardware, and configured such that the parallel or substantially parallel edges will fit snugly around a saddle in the base plate when the apparatus is assembled, as described herein. The distance between the parallel edges may be any suitable distance. In one embodiment, the PCB and the backer plate are connected with ½ inch standoffs. 
     PCB  11  as depicted in  FIG. 1  is not limited to a PCB. The PCB  11  may include a PCB and/or may include other component(s) in addition to or in place of a PCB, in the apparatus described herein. “PCB” herein may refer to a PCB or another component, as described herein. For example, any planar or substantially planar component or a component on a planar or substantially planar backer plate may be secured, for example, in an electronic device, computer, server, etc., as described herein. Non-limiting examples of such components include one or more hard drives and/or one or more PCB&#39;s secured to a backer plate, or a display. Generally, the apparatus is designed and dimensioned to meet the requirements of the PCB or other component to be secured. 
     The backer plate  12  may be constructed of any material that will maintain structural integrity when assembling the FRU and when held in place in the assembled apparatus, e.g., when fitted around and held in place around a saddle, as described herein. Suitable materials include, but are not limited to, aluminum, steel, plastic, metal, wood, composite, etc. The backer plate may be constructed in any way that will produce a material that will maintain structural integrity, for example, but not limited to, pressed, cut, layered, etc. The backer plate could also be another PCB. In one embodiment, the backer plate comprises aluminum. 
     A “standoff”  13  herein refers to a spacer that separates two parts from one another, e.g., a separator between the PCB and the backer plate. Any “separator” hardware may be used in place of or in addition to Standoffs  13  that separates the two plates and maintains the integrity of the separation such that the plate faces remain in a parallel configuration in the apparatus. 
     The base plate  20  may be constructed of any material that will maintain structural integrity in the assembled apparatus, e.g., when the FRU is fitted into and maintained in place around the saddle, as described herein. Suitable materials include, but are not limited to, aluminum, steel, plastic, metal, wood, composite, etc. The base plate may be constructed in any way that will produce a material that will maintain structural integrity, for example, but not limited to, pressed, cut, layered, etc. In one embodiment, the base plate comprises aluminum plate. 
     A pocket  21  may comprise any dimensions of length, width, corner radius, and depth that are suitable to receive and retain an edge of the FRU as described herein. Generally, the corner radii are used to adjust the distance between the saddle edge and the PCB. 
     An apparatus as disclosed herein includes a PCB and a backer plate with faces that are parallel or substantially parallel and held apart by separators (a “FRU”), secured by fitting the parallel faces of the FRU around a saddle that is a raised area between two pockets in a base plate, such that when the FRU is fitted around the saddle, movement of the PCB and backer plate is substantially reduced or eliminated. 
     In one embodiment, the base plate does not include pockets, and the saddle is a raised area relative to a planar base plate, with parallel edges around which the PCB and backer plate are secured by tightly fitting around and in contact with the edges of the saddle. 
     To achieve the intended results of this invention, FRU  10  and a Base Plate  20  are produced as described above. The FRU  10  is then lowered toward the Base Plate such that the PCB  11  and the Backer Plate  12  straddle a saddle  23 . An embodiment of an assembled apparatus is shown in  FIG. 2 . The bottom edges  14  of the PCB and Backer Plate should squarely contact the bottom of the Pockets  21 . 
     There are many alternative ways this invention can be implemented, including but not limited to embodiments as described below. 
     In some embodiments, the rear face of the PCB  11  does not contact the side edge of the saddle  23 . Rather, PCB lower corners  15  and  16  contact the Pocket Corner Radii  31  and  32  at their furthest point from the saddle  23  as shown in  FIG. 3 , to provide clearance for solder joints and/or protrusions  33 ,  34  on the rear of the PCB  11  if necessary. In one embodiment, the distance between the back face of the PCB and the edge of the saddle is about ⅛ inch. In some embodiments, the PCB or backer plate face contacts the edge of the saddle, as shown in  FIG. 2 . 
     In some embodiments, bottom edges of the PCB and backer plate contact the recessed surface of the pocket. In other embodiments, bottom edges of the PCB and backer plate do not contact the recessed surface of the pocket. 
     In some embodiments, separators contact the surface of the saddle. In other embodiments, the separators do not contact the surface of the saddle. In some embodiments, the saddle comprises grooves into which the separators fit when the apparatus is assembled. 
     In some embodiments, in the assembled apparatus, the faces of the PCB and backer plate are at a 90 degree angle or substantially at a 90 degree angle relative to the base plate. In some embodiments of the assembled apparatus, at least a portion of the face of the PCB and at least a portion of the face of the backer plate, each of which portions are contiguous with the edges that are fitted around the saddle, are at a 90 degree angle or substantially at a 90 degree angle relative to the base plate. 
     In some embodiments, instead of a PCB and an inert backer plate, the FRU may comprise two PCBs, with edges that are parallel or substantially parallel to each other configured to fit around a saddle, as described herein, i.e., the backer plate is a PCB. In some embodiments, other components are mounted to the backer plate for example, a hard drive, display, etc. 
     In some embodiments, all components (e.g., backer plate, base plate) may be made of the same or different materials as needed. 
     In some embodiments, all components (e.g., backer plate, base plate) may be sized and depths and radii adjusted as needed. 
     In various embodiments, the manufacturing of the Base Plate  20 , e.g., production of pockets  21  in plate material, can be accomplished in a number of ways, including but not limited to, computer numerical control (CNC) milling/routing, layered sheeting, molding, etc. 
     In some embodiments, another plate may be substituted for PCB  11 . For example, a second backer plate may be substituted, and other devices or smaller PCB&#39;s may be mounted onto the second backer plate. 
     In various embodiments, the Base Plate  20  may be mounted in an enclosure, may be part of an enclosure, or may be standalone as needed. 
     In some embodiments, a secured cover could be used to capture the FRU  10  such that it cannot escape the saddle  23 . For example, a cover may be secured, e.g., screwed or otherwise held or clipped down so that it can&#39;t move. For example, a chassis cover may include a bolted or secured lid. 
     In some embodiments, backplanes, connections, adapters etc. could be used in conjunction with the FRU  10  and Base Plate  20 . 
     In some embodiments, other devices can be mounted to the PCB Backer Plate  12  for example, hard drives. 
     In some embodiments, latching mechanisms could be used such that the FRU  10  could not escape the saddle  23  allowing vertical placement of the Base Plate  20 . 
     In some embodiments, any number of Saddles  23  can be created in the Base Plate  20  in any configuration including both faces as needed. In various embodiments, multiple saddles may be configured parallel to each other or at any angle relative to one another, depending on the requirements or configuration of the device into which the FRU&#39;s will be incorporated. 
     In some embodiments, additional pockets can be cut in the Base Plate  20 , or additional cutouts of greater depth within the pockets that surround a saddle, to allow clearance for protrusions from the FRU  10 . 
     Although the foregoing invention has been described in some detail by way of illustration and examples for purposes of clarity of understanding, it will be apparent to those skilled in the art that certain changes and modifications may be practiced without departing from the spirit and scope of the invention, which is delineated in the appended claims. Therefore, the description should not be construed as limiting the scope of the invention.