Abstract:
A power connector is configured to float on a computer backplane allowing bulk power supplies to be physically located adjacent to the backplane. This allows use of an EMI gasket between the bulk power supply and the backplane preventing high frequency noise from radiating out of the computer case. Standard electrical plugs may be used on one or both sides of the power connector allowing standard bulk power supplies and line cords to be used on one or both sides of the power connector.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates generally to the field of electrical hardware and more specifically to the field of electrical power connectors for use in electrical hardware.  
         BACKGROUND OF THE INVENTION  
         [0002]    Many electrical devices include an internal bulk power supply (BPS) used to convert alternating current (AC) power supply signals to lower voltage direct current (DC) power supply signals. Often a connector is attached to the chassis of the electrical device allowing a separate power cord to plug into the device. The connector is electrically connected to the bulk power supply within the chassis, often with wires from the connector to the BPS.  
           [0003]    This common configuration creates a number of problems. Many electrical components, such as integrated circuits, may be susceptible to electromagnetic interference (EMI) inherent in high frequency components of the AC power supply signals. A variety of methods are commonly used to reduce this interference. AC line filters are used to reduce the high frequency components of the AC power supply signals. Shielding is often used around the power supply to contain high frequency emissions from the bulk power supply within the system. However, shielding adds to cost and makes replacement of the power supply more difficult.  
         SUMMARY OF THE INVENTION  
         [0004]    An AC-to-AC adapter is configured to float on a computer chassis, backplane, or wall of a computer case allowing bulk power supplies to be physically located adjacent to the backplane. This allows use of an EMI gasket between the bulk power supply and the backplane preventing high frequency noise from radiating out of the computer case. Standard electrical plugs may be used on one or both sides of the adapter allowing standard bulk power supplies and line cords to be used on one or both sides of the adapter. 
       
    
    
       [0005]    Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.  
       BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    [0006]FIG. 1 is a front view of an example embodiment of an AC-to-AC adapter according to the present invention.  
         [0007]    [0007]FIG. 2 is a back view of the example embodiment of an AC-to-AC adapter of FIG. 1 according to the present invention.  
         [0008]    [0008]FIG. 3 is a top view of the example embodiment of an AC-to-AC adapter of FIG. 1 according to the present invention.  
         [0009]    [0009]FIG. 4 is a side view of the example embodiment of an AC-to-AC adapter of FIG. 1 according to the present invention.  
         [0010]    [0010]FIG. 5 is a front view of an example embodiment of an AC-to-AC adapter according to the present invention.  
         [0011]    [0011]FIG. 6 is a side view of the example embodiment of an AC-to-AC adapter of FIG. 1 according to the present invention attached to a bulk power supply and a chassis.  
         [0012]    [0012]FIG. 7 is an example embodiment of a computer system including an AC-to-AC adapter according to the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0013]    [0013]FIG. 1 is a front view of an example embodiment of an AC-to-AC adapter  100  according to the present invention. This example embodiment of the present invention is an AC-to-AC adapter  100  configured to attach to a backplane on an electrical device. The front view of the adapter shows the side of the adapter  100  that resides on the outside of the electrical device. The AC-to-AC adapter  100  shown in FIG. 1 includes an outside AC connector  102  including a ground pin  104  and hot and neutral pins  106 . The ground pin  104  is electrically connected to a ground wire  108  through the body of the AC-to-AC adapter  100  with a wire  110  or other electrically conductive material. The ground wire  108  is terminated in a ground connector  112  allowing electrical connection between the ground pin  104  and the backplane of an electrical device. In this example embodiment of the present invention the outside AC connector  102  is a standard IEC 320 (as of Jan. 1, 2002) 20 amp receptacle that accepts a standard IEC 320 (as of Jan. 1, 2002) 20 amp plug. Many other configurations of the outside AC connector  102  may be substituted within the scope of the present invention. Since the adapter  100  includes a ground wire  108  that may be electrically connected to a backplane, the adapter  100  does not need to allow for electrical connection to ground through the means for connecting the adapter  100  to a backplane. The adapter may then move up and down, or side to side with respect to the backplane as needed to allow for misalignments in a bulk power supply as it is attached to the adapter  100  within the electrical device that the adapter  100  is attached to.  
         [0014]    Many current computer chassis include a power connector externally similar to that of the present invention. However, in many cases power wires are used to bring power from the connector to an internal bulk power supply. Some computer chassis include metal shielding completely surrounding the bulk power supply, wire, and connector, however, this adds cost to the computer system, and adds to repair time required to change out a failed power supply.  
         [0015]    The AC-to-AC adapter  100  of the present invention allows construction of bulk power supplies configured to plug directly into the adapter  100  and to include a built-in AC line filter. The connection between the AC-to-AC adapter  100  and the bulk power supply may then be EMI shielded from the rest of the computer through the use of an EMI gasket between the bulk power supply and the chassis surrounding the connection between the adapter  100  and the bulk power supply. Since the case of the bulk power supply acts as an EMI shield, using an EMI gasket between the bulk power supply and the computer chassis fully encloses all AC power supply lines within an EMI shield.  
         [0016]    For safety reasons, the case of the bulk power supply must be electrically connected to the computer chassis and ground. If the case of the power supply is allowed to float while connected to an AC power source, dangerous voltages may develop between the case and ground. Thus, the case of the power supply must be securely electrically connected to ground while power is applied. Many computer systems use a separate wire from the case of the bulk power supply to the computer chassis to ground the power supply case. When replacing bulk power supplies, power to the supply must be shut off before removing this ground wire, thus making hot swapping of the power supply more time consuming and possibly dangerous. The AC-to-AC adapter  100  of the present invention eliminates the necessity of this separate wire since the ground pin/slot is electrically connected to a ground wire  108  that is then electrically connected to the backplane or chassis with a ground connector  112 . When the bulk power supply is plugged in to the adapter  100 , the ground connection to the backplane or chassis is also accomplished. Thus, safe hot swapping of the bulk power supply may now be possible.  
         [0017]    Some computer system designers use EMI shielding gaskets between the case of the bulk power supply and the computer backplane or chassis to act also as a ground connection between the power supply and the chassis. However, when removed from the chassis, EMI shielding may be delicate and prone to damage, thus raising the possibility of poor ground integrity throughout the life of the computer system. The AC-to-AC adapter  100  of the present invention reduces that risk since the ground connection  110  is within the adapter itself and is undisturbed during replacement of the bulk power supply.  
         [0018]    [0018]FIG. 2 is a back view of the example embodiment of an AC-to-AC adapter of FIG. 1 according to the present invention. This example embodiment of the present invention is an AC-to-AC adapter  100  configured to attach to a backplane on an electrical device. The back view of the adapter shows the side of the adapter  100  that resides on the inside of the electrical device. The AC-to-AC adapter  100  shown in FIG. 2 includes an inside AC connector  200  including a ground slot  202  and hot and neutral slots  204 . The ground slot  202  is electrically connected to the ground pin  104  shown in FIG. 1. The ground slot  202  is also electrically connected to the ground wire  108  through the body of the AC-to-AC adapter  100  with a wire  110  or other electrically conductive material. The ground wire  108  is terminated in a ground connector  112  allowing electrical connection between the ground slot  202 , the ground pin  104  and the backplane of an electrical device. The inside AC connector  200  is configured to connect to a standard bulk power supply. In this example embodiment of the present invention the inside AC connector  200  is a standard IEC 320 (as of Jan. 1, 2002) 20 amp plug that connects with a standard IEC 320 (as of Jan. 1, 2002) 20 amp receptacle. Many other configurations of the inside AC connector  200  may be substituted within the scope of the present invention. This connector  200  may be configured to connect to any desired bulk power supply or any other electrical device within the scope of the present invention. Since the adapter  100  includes a ground wire  108  that may be electrically connected to a backplane or chassis, the adapter  100  does not need to allow for electrical connection to ground through the means for connecting the adapter  100  to a backplane or chassis. The adapter may then move up and down, or side to side with respect to the backplane or chassis as needed to allow for misalignments in a bulk power supply as it is attached to the adapter  100  within the electrical device that the adapter  100  is attached to.  
         [0019]    [0019]FIG. 3 is a top view of the example embodiment of an AC-to-AC adapter of FIG. 1 according to the present invention. This example embodiment of the present invention is an AC-to-AC adapter  100  configured to attach to a backplane on an electrical device. The top view of the adapter shows the adapter  100  that is configured to connect to a backplane or chassis allowing movement in two axes. The example embodiment of the present invention includes two cutouts  300  configured to allow attachment to a backplane or chassis with some up and down, and side to side movement, but little in and out movement with respect to the backplane or chassis. Many other attachment means may be used within the scope of the present invention to attach the adapter  100  to a backplane or chassis. This top view shows both the inside AC connector  200  and the outside AC connector  102 . The ground wire  108  has been removed for illustration purposes and the wire  110  or other electrical conductor used to connect the ground pin  104  and ground slot  202  is shown on the top of the adapter  100 .  
         [0020]    [0020]FIG. 4 is a side view of the example embodiment of an AC-to-AC adapter of FIG. 1 according to the present invention. This example embodiment of the present invention is an AC-to-AC adapter  100  configured to attach to a backplane on an electrical device. The side view of the adapter shows the adapter  100  that is configured to connect to a backplane or chassis allowing movement in two axes. The example embodiment of the present invention includes two cutouts  300  configured to allow attachment to a backplane or chassis with some up and down, and side to side movement, but little in and out movement with respect to the backplane or chassis. Many other attachment means may be used within the scope of the present invention to attach the adapter  100  to a backplane or chassis. This side view shows both the inside AC connector  200  and the outside AC connector  102 .  
         [0021]    [0021]FIG. 5 is a front view of an example embodiment of an AC-to-AC adapter according to the present invention. This example embodiment of the present invention is an AC-to-AC adapter  500  configured to attach to a backplane on an electrical device. The front view of the adapter shows the side of the adapter  500  that resides on the outside of the electrical device. The AC-to-AC adapter  500  shown in FIG. 5 includes an outside AC connector  502  including a ground pin  504  and hot and neutral pins  506 . This example embodiment of the present invention is similar to the embodiment shown in FIGS. 1 through 4 with the exception of the outside AC connector  502 . In this example embodiment a different outside AC connector  502  is used with a different configuration of ground  504  and hot and neutral pins  506 . The ground pin  504  is electrically connected to a ground wire  508  through the body of the AC-to-AC adapter  500  with a wire  510  or other electrically conductive material. The ground wire  508  is terminated in a ground connector  512  allowing electrical connection between the ground pin  504  and the backplane of an electrical device. The outside AC connector  502  is configured to connect to a standard electrical power cord. This connector  502  may be configured to connect to any desired electrical power cord within the scope of the present invention. Since the adapter  500  includes a ground wire  508  that may be electrically connected to a backplane, the adapter  500  does not need to allow for electrical connection to ground through the means for connecting the adapter  500  to a backplane. The adapter may then move up and down, or side to side with respect to the backplane as needed to allow for misalignments in a bulk power supply as it is attached to the adapter  500  within the electrical device that the adapter  500  is attached to.  
         [0022]    [0022]FIG. 6 is a side view of the example embodiment of an AC-to-AC adapter of FIG. 1 according to the present invention attached to a bulk power supply and a chassis. This view of the AC-to-AC adapter includes the bulk power supply  602  that connects to the adapter  100  along with the chassis  600  that the adapter  100  is attached to in a method allowing movement in two axes. EMI shielding  604  material is shown between the chassis  600  and the power supply  602 . This EMI shielding  604  contains the high frequency noise from escaping through the connector system chassis openings, and may be an EMI gasket.  
         [0023]    [0023]FIG. 7 is an example embodiment of a computer system including an AC-to-AC adapter according to the present invention. The computer system shown in FIG. 7 includes an enclosure  700  surrounding at least part of a chassis  600  including a power supply  708  that is connected to an AC-to-AC adapter  100  that, in turn, is mechanically connected to the chassis  600  in a method allowing movement in two axes, and is electrically connected to the chassis  600  through a ground wire  108  and ground connector  112 . The computer system includes a display  702 , a keyboard  704 , and a mouse  710 .  
         [0024]    The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and other modifications and variations may be possible in light of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. It is intended that the appended claims be construed to include other alternative embodiments of the invention except insofar as limited by the prior art.