Abstract:
An adaptor is provided for effectively converting an opening in the chassis or box of a router (or similar device) from an opening which accommodate a power entry component for a first power type to accommodate a power entry component for a second power type. In one aspect, an adaptor fits in a panel opening which is sized and shaped to receive an IEC-compliant AC power entry component. The adaptor has a window or opening which accommodates, e.g. a four-wire DC power entry component. In one aspect, an adaptor couples to screw holes, such as on either side of an RPS coupler and also receives a standard ground wire log, preferably forming a conductive path from the lug to the screw holes.

Description:
The present invention relates to a method and apparatus for accommodating first and second power types and in particular a method and apparatus to configure networking/telecommunications devices to accommodate either of a first and second power type such as AC power and DC power. 
     BACKGROUND INFORMATION 
     A number of devices which have uses in networking and/or telecommunications applications, such as switches, routers, hubs, bridges, gateways, and the like, are configured for receiving electrical power from an external source or line. A number of different power types are used including various voltages of alternating current (AC) and/or direct current (DC). For example, many common telecommunications devices are configured for AC power such as 110 volt, 60 hertz AC power in North America, 220 V. in Europe and the like. Many telecommunications devices are configured for DC power such as 48 volt DC power in North America. 
     Typically, devices which accommodate different power sources are configured differently, such as by providing different power supply devices or circuitry and/or providing different power entry configurations or components. Power supplies are often provided as substantially modular components which can be physically and electrically coupled to other electronic components in a networking or telecommunications device. Power entry configurations or components in general refers to plugs or similar couplings, and corresponding chassis openings, for connecting power lines, ground lines and the like, for purposes of transmitting power or ground through the chassis or body of a device, to the power supply or other internal components of the device. 
     Many power entry components are configured as, or include, plugs, jacks or couplings which are mounted on and/or extend at least partially through a wall of a box or chassis. A number of standards have been developed defining configurations for power entry components which are typically unique to various power types, e.g., to avoid coupling the wrong power type to a networking or telecommunications device. For example, a four-lead DC power entry component has a shape which is substantially different from a 110 volt single-phase grounded AC power entry component, e.g., as defined by the International Engineering Consortium (IEC) (IEC-compliant). Because the plug configurations are typically made purposely differently, for different power types, such plugs are often configured for coupling to a chassis or box opening having a size and/or shape which is substantially unique to that power type. As a result, in a typical situation, when a networking or telecommunications device is designed, the box or chassis for such device will be designed to either accommodate a plug or other power entry component for a first power type or accommodate a plug or other power entry component for a second power type. For example, a chassis intended for an IEC AC power entry component will be provided with a 28 mm by 20 mm opening in the chassis or box while a chassis or box intended for DC power supply will be provided with a 20 mm by 15 mm opening (as well as, perhaps, other components, e.g., for accommodating a ground lug and the like). 
     Approaches which provide different chassis or boxes, depending on the intended power type (even when other functions of the electronic component may be similar to one another or substantially the same) presents a number of problems. The differences can constrain manufacturing logistics, e.g. since the different products may be produced on separate manufacturing lines, and the like. There are a number of expenses associated with providing a box or chassis for accommodating a power type, including design time and other expenses associated with determining the size, shape and location of openings, screw holes or other mounting components and the like, especially when openings must be positioned to accommodate proper configuration of cables and the like with respect to a power supply or other interior components and must fulfill other design constraints such as avoiding uncovered openings (which can create undesirable levels of electromagnetic interference, safety concerns and the like), the cost of designing and creating tooling to provide the desired openings in the (typically sheet metal) chassis or box, the cost of designing, producing or installing screw holes, clips or other couplings configured to hold the power entry components, and/or the cost of maintaining an inventory of two or more different types of chassis or boxes. The per-unit cost can be especially burdensome when a manufacturer produces relatively few of one of the configurations. Accordingly, it would be useful to provide a system, method and apparatus for providing a single chassis, box or panel configuration which can be used in providing equipment configured for either of a first or second power type (such as AC power or DC power). Although embodiments of the present invention have been described in connection with power for networking or telecommunications devices, there is no theoretical reason why the invention cannot be used in connection with other types of devices such as personal computers or laptop computers, hand-held computers, portable electronic items such as telephones, pagers, office equipment, entertainment devices and the like. 
     Previous approaches which used different box or chassis configurations for different power types made it difficult or infeasible to convert an apparatus which was originally intended for a first power type, into an apparatus which could use a second power type. Accordingly, it would be useful to provide a method, system or apparatus which can readily achieve a power-type conversion or retrofit capability between two or more different power types. 
     SUMMARY OF THE INVENTION 
     The present invention includes a recognition of the existence, source and/or nature of problems in previous approaches, including as described herein. In one aspect, an adaptor is provided which can couple to a power entry component intended for a first power type and which can also couple to an opening or coupling of a chassis, box or panel which is intended for a second, differently sized or shaped power entry component (or adaptor) for a second power type. In one illustrative example, a networking or telecommunications device has a chassis which includes an opening sized and shaped to accommodate a standard, commercially available AC power entry plug or coupling, e.g., complying with IEC standards. An adaptor is provided which has an exterior perimeter and/or couplings configured to fit in, or couple to, the opening but which also has an interior opening or window configured to accommodate and/or couple a DC power entry component, preferably a standard, commercially available DC power entry component. By coupling the DC power entry component to the adaptor and coupling the adaptor to the AC opening, a DC power entry component can be accommodated in a chassis or box which was configured for accommodating an AC power entry component, substantially without modification, redesign, retooling and the like in fabricating the chassis or box. 
     In one embodiment, the chassis or box of a networking or telecommunications device includes an opening for accommodating a remote power supply pin (RPS) coupling or connector which includes a first set of connector-mounting screw holes, spaced-apart a first distance. An adaptor is provided which can be mounted to the first set of screw holes so as to both cover the RPS opening (which is not needed in, or used in, a DC configuration) and to provide a second set of screw holes, in the adaptor, spaced apart a second distance, which is defined to accommodate a standard, commercially available, ground wire lug. In this way, not only is an opening desirably covered, but a opportunity for mounting a standard ground lug is provided without having to provide additional screw holes. Preferably, the adaptor is formed of a substantially conductive material or otherwise provides a conductive pathway from the ground lug to the chassis or box. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1A and 1B are simplified rear perspective, partially cutaway views showing the external appearance of a box or chassis configured for AC power and DC power respectively; 
     FIG. 2 is a partial rear perspective view, partially exploded, depicting adaptors for accommodating DC power entry components in a chassis or box configured for AC power, according to an embodiment of the present invention; 
     FIG. 3 is an elevational view of a ground lug adaptor according to an embodiment of the present invention; 
     FIG. 4 is an elevational view of a power entry plug converter according to an embodiment of the present invention; and 
     FIG. 5 is a side view of the converter of FIG.  4 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1A illustrates a typical AC-configured box (e.g., of a router, hub, gateway or other component of a network) according to previous approaches. In the configuration of FIG. 1A, an AC entry component  112  is accommodated in a cutout or opening  114  in a rear panel  116  of the box  118  with the cutout having a first height  122  of about 20 mm and a width  124  of about 28 mm. In the depicted embodiment, the rear panel  116  also includes an RPS coupling  126  positioned in a cutout  128  having a height  132  and width  134 . Threaded holes  136   ab,  e.g., for securing a connector or fastener, form a hole pattern in the depicted embodiment, being a pair of holes  136   a,b  spaced a distance apart  138 . 
     As will be understood by those of skill in the art, the interior of the box  118  commonly contains a number of electronic components including, e.g., a main circuit board or motherboard  142  with power supply  144  (which receives AC power via the power entry  112  and wires or cables (not shown) and outputs power for use by the circuitry at one or more predefined voltages) coupled by screws or bolts or rivets  146   a,b  with a predefined spacing  148 . 
     FIG. 1B depicts a chassis or box  158  of a type that may be used for a DC implementation. In the configuration of FIG. 1B, a DC power entry plug  152  is positioned in a cutout  154  in a rear panel  156  having a height  162  and a width  164 . The cutout height  162  and width  164  for accommodating the DC plug  152  is, in general, substantially different from the cutout height  122  and width  124  for accommodating the AC plug  112  (FIG.  1 A). For example, in the AC configuration, the height  122  may be about 20 mm, the width  124  may be about 28 mm, whereas in the DC configuration, height  162  may be about 15 mm and the width  164  may be about 20 mm. Accordingly, in general, if it is desired to provide both AC configurations (FIG. 1A) and DC configurations (FIG. 1B) it is necessary to design, fabricate and stock two different chassis or boxes, a first  118  with openings  114  configured for AC power entry and a second  158  with openings  154  configured for DC power entry. 
     In the configuration of FIG. 1B, a ground wire lug  166  is coupled with bolts, screws or rivets defining a ground lug hole pattern in the depicted embodiment being a pair of holes  168   a,b  spaced a distance apart  172  which, in general, will be different from the spacing  138  of the threaded holes  136   ab  associated with the RPS of the AC configuration (FIG.  1 A). Preferably, the lug adaptor is formed of a substantially conductive material, or coated, with a substantially conductive material and the screw holes  236   a,b  are used for coupling to a ground wire to provide a conductive path from the ground lug to a ground wire. In one embodiment, the lug adaptor is formed from tin-plated steel. The DC power supply  174  can be provided in a size, shape and hold spacing  148  to be accommodated in substantially the same space, and in the same manner, as the AC supply  144  in the AC configuration (FIG.  1 A). 
     FIG. 2 illustrates one manner in which, according to an embodiment of the present invention, the same chassis  118  can be used for both an AC configuration and a DC configuration, without the need to substantially modify or redesign the chassis. As shown in FIG. 2, the chassis  118  includes, in its rear panel  116 , a cutout  114  of a size and shape configured to accommodate a AC power entry (as illustrated in FIG.  1 A). However, in the embodiment of FIG. 2, rather than the cutout  114  receiving an AC power entry plug  112 , it instead, receives an adaptor  214  which defines an opening  216  sized and shaped to receive the DC power entry unit  152 ′. As best seen in FIG. 4, the adaptor  214  has exterior dimensions defining a height  122  and width  124  to fit in or be accommodated by the (AC-shaped) opening  114 . However, an interior opening or window  216  has a height  162  and width  164  which accommodates at least the coupling area of the DC plug  152 . In one embodiment, the window height  262  is substantially equal to the height  162  of the opening in the DC configuration and the window width  264  is substantially equal to the width  164  of the power entry opening  154  of the DC configuration of prior approaches (FIG.  1 B). 
     Preferably, the adaptor  214  can be positioned or coupled within the opening  114  without the need for separate fasteners and/or tools. In the embodiment best seen in FIG. 5, the adaptor  214  is provided with a plurality of resilient tabs  512   abc.  The rearward portion  514  of the adaptor  214  is inserted  218  through the opening  114  with the resilient tabs  512   abc  being deflected inwardly to permit their passage through the opening  114 . Once passing through the opening  114  the resilient tabs  512   abc  return to their undeflected positions as depicted in FIG. 5 so as to capture the thickness of the rear panel  116  within the space  516  defined between the tabs  512   a,    512   b,    512   c  and the front portion or plate  518  of the adaptor  214 . Although a number of configurations are possible, in the depicted embodiment the lower surface of the adaptor  214  has a length  522  of about 24 mm and the upper surface has a length  524  of about 27 mm. Those of skill in the art will understand how to devise other shapes and configurations for an adaptor  214  such that the adaptor will be accommodated in or be coupled to the opening  114  and can receive at least the coupling portion of a DC entry module  152 ′. 
     As seen in FIG. 1A, the AC configuration does not include specific openings for coupling a ground lug. In the embodiment of FIG. 2, a lug adaptor  232  is provided which defines or includes threaded holes  234   ab  (or other openings or cutouts) with a spacing equal to the spacing  172  of a ground lug  166  so that the ground lug  166  can be readily coupled to the adaptor  232 , e.g., using screws, bolts, and the like (not shown). The lug adaptor  232  also includes coupling devices such as bolt or screw holes  236   ab  for coupling to the box or chassis  118 . Since it is preferred to avoid having to make modifications or changes to the AC chassis or box  118 , preferably the lug adaptor  232  can be coupled to the chassis  118  without creating or providing additional screw holes or the like. In the depicted embodiment, the lug couplings  236   ab  are sized and spaced to match the RPS threaded holes  136   ab  so that the lug adaptor  232  can be fastened to the chassis  118  in a position substantially covering the RPS opening  128 . This configuration not only provides the advantage of avoiding the need for new holes or similar devices in order to attach the lug adaptor  232  (and made possible by the fact that an RPS is typically not used in a DC environment) but also can be used to cover the RPS opening  128  (whether or not an RPS connector  126  is provided within the opening  128 , which can be useful in avoiding unwanted electromagnetic interference, safety concerns and the like). 
     In operation, when it is desired to provide a AC component, an AC-type box or chassis  118  can be provided and outfitted as depicted in FIG.  1 A. However, when it is desired to provide a corresponding DC component, the same box or chassis  118  can be provided and assembly personnel can be furnished with a package of DC components including adaptor  214 , adaptor lug  232 , as well as the DC components normally provided such as DC power entry module  152 ′, ground lug  166  and DC power supply  174 . By installing the adaptors and other components as depicted in FIG.  2  and coupling the DC power supply  174 , a DC component is provided using a substantially unmodified AC chassis or box  118 . 
     In light of the above description, a number of advantages of the present invention can be seen. The present invention can be used to provide relatively easy product conversion from AC to DC power. Preferably the change can be implemented substantially as a manufacturing change (as opposed to, e.g., an engineering change). For example, the change can be accomplished with a bill of materials (BOM) change, i.e., substantially without the need for making sheet metal or other changes to a chassis or box, thus achieving a relatively inexpensive manner of providing a DC power supply conversion. Preferably, some or all adaptors or other parts are installed by a snap-in installation, without the need for separate screws or similar fasteners and without the need for tools, or, in some cases, using only simple hand tools such as screwdrivers, nut drivers and the like. The present invention can be applied to a wide variety of electronic devices to provide multiple different power type versions using the same chassis or box. Some or all features of the present invention can be used to retrofit into existing chassis designs or boxes and/or existing assembled electronic components to provide for a different power supply type. The present invention can substantially avoid uncovered openings so as to assist in reducing electromagnetic interference, safety concerns and the like. 
     A number of variations and modifications of the invention can be used. It is possible to use some features of the invention without using others. For example, it is possible to use the power entry adaptor without using the lug adaptor and the like. Although power entry is traditionally provided in a rear panel, there is no theoretical reason why the present invention cannot be used in electronic components with power entry in other regions or surfaces. In some embodiments, it may be desired to provide an opening which is larger than the opening for any of a plurality of desired power types and to provide for adaptors for each desired power type. Although it is preferred to form the power entry adaptor from injection-molded plastic, it is also possible to form the adaptor form other materials such as resins, fiberglass, ceramic and the like. Although, in one embodiment, the ground lug adaptor is formed from tin-plated steel, other materials achieving the desired conductive pathway can be used including aluminum or plated copper. Although a specific example, with specific associated sizes, relating to IEC-AC power entry and DC power entry components has been described, the present invention can be used in connection with any of a variety of power types including 220 volt power supplies of the type common in Europe, three-phase power, various voltages of DC power and/or numerous different shapes and sizes of power entry modules or plugs. Although an embodiment was described in which an opening can accommodate either an unmodified entry component for a first power type or an entry component for a second power type, other configurations are also possible. For example, it is possible to use a configuration in which a collar or adaptor for both an entry component for a first power type and an entry component for a second power type is used, with a chassis, box or panel opening configured to accommodate either of the two adaptors. It is possible to provide a chassis, box or panel opening which accommodates two or more entry component adaptors. It is possible to configure an adaptor to perform a function in addition to its adaptor function, such as holding or guiding cables or other components and the like. Although it is believed economically preferable to use an adaptor for fitting a standard sized, commercially available entry component to an opening, it would be possible (even if not economically advantageous) to provide a single part which performs the functions of both standard entry component and adaptor (e.g., by reconfiguring the peripheral shape and/or size of a standard power entry component). Although an embodiment was depicted in which the adaptor defines a substantially rectangular opening and in which the chassis or box opening is substantially rectangular. The present invention can be used in connection with other sizes or shapes of openings. Although the adaptor opening as depicted has opening edges which are spaced from exterior adaptor edges, it is also possible to provide an opening with one or more edges contiguous with adaptor edges and/or panel opening edges. Although in the depicted embodiment, the ground lug hole pattern and chassis hole pattern are pairs of spaced apart holes, the present invention can also be implemented in embodiments in which either or both of the ground lug hole and/or chassis hole patterns are different patterns such as forming a triangular pattern, quadrilateral pattern, circular pattern, array or grid, and the like. Although the depicted embodiments illustrate connector receiving areas  234   ab  which are in the form of threaded holes, other connector receiving areas can be used such as through holes, un-shaped cutouts, latches and the like. 
     The present invention, in various embodiments, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various embodiments, subcombinations, and subsets thereof. Those of skill in the art will understand how to make and use the present invention after understanding the present disclosure. The present invention, in various embodiments, includes providing devices and processes in the absence of items not depicted and/or described herein or in various embodiments hereof, including in the absence of such items as may have been used in previous devices or processes, e.g. for improving performance, achieving ease and/or reducing cost of implementation. The present invention includes items which are novel, and terminology adapted from previous and/or analogous technologies, for convenience in describing novel items or processes, do not necessarily retain all aspects of conventional usage of such terminology. 
     The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. Although the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the invention, e.g. as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.