Patent Publication Number: US-11050199-B1

Title: AC adapter with tethered removable plug

Description:
FIELD OF THE INVENTION 
     Embodiments of the disclosure described herein are directed to the field of convertible AC power adapters with removeable plugs, which allow the adapter to be directly plugged into a power source, such as a wall outlet, or when removed, may be swapped out with a corded plug or other type of plug module. More specifically, embodiments of the disclosure are directed to an AC adapter having an internal cavity which contains an extension cord that is in electrical engagement with the adapter and the removeable plug. The cord may be deployed from within the adapter when the removeable plug is disconnected from the adapter body thereby providing the adapter with its own built in extension cord and alleviating the need for a second corded plug module. 
     BACKGROUND OF THE INVENTION 
     AC adapters, AC/DC adapters or “power adapters” as they are sometimes referred to, are external power supplies that are ubiquitous to modern consumer electronics. From so called “power bricks” with a cord at both ends for supplying power to a personal computer, to direct plug in, single cord, “wall wart” adapters common to cellular phones; AC adapters convert electrical AC current from the power source (typically a wall outlet) to DC voltage, which is then supplied to a consumer electronic device connected at the other end. 
     Many modern AC adapters are convertible between a direct plug-in capability, to one that uses an extension cord that is plugged directly into the adapter in place of the nominal plug. Examples of such convertible AC adapters may be found in U.S. Design Pat. Nos. D661,649; D784,921. These types of adapters come equipped with a plug, with foldable pins or blades that may lay flat within the adapter housing and which may be folded outward from the adapter to allow them to interface with an electrical outlet. In the event that the adapter cannot reach an outlet, or the adapter is too large or heavy to practicably connect to the outlet directly, the plug may be swapped out from the adapter housing and replaced with an extension cord that interfaces with the adapter in the same manner as the original plug. This arrangement however necessitates the adapter having both the remove plug and the extension cord components, wherein one of these components must be separately stored (or discarded) when the other is in use. 
     SUMMARY OF THE INVENTION 
     The adapter of the present disclosure is provided with a unique design that eliminates the need for extraneous components by providing the adapter with a unitary plug and extension cord tethered to the adapter. One end of the cord terminates in the plug, and the other end is connected to the electrical components of the adapter within a storage cavity defined by the adapter housing. When the plug is in place on the housing for directly connecting the adapter to an outlet, the extension cord is entirely contained within the storage cavity. When the cord is needed, the plug is disconnected from the adapter housing, and the cord is withdrawn from the cavity while maintaining the electrical connection with the adapter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of an AC adapter shown with an extension cord stored within a storage cavity and the pins of the plug are shown in the folded position. 
         FIG. 2  is a perspective view of the AC adapter shown in  FIG. 1 , with the plug pins shown in the extend position. 
         FIG. 3 . is a perspective view of the AC adapter shown in  FIG. 2 , depicted within a typical environment of use, wherein the adapter is shown plugged directly into a wall outlet and a USB (or functionally equivalent) power cord is provided to supply power from the adapter to an electronic device. 
         FIG. 4  is the same view as shown in  FIG. 4  wherein the USB power cord is connected to the USB port of the adapter and to the receiver port of the electronic device. 
         FIG. 5  is a perspective view of the AC adapter of  FIGS. 1-2  shown with the plug disconnected from the adapter housing and the extension cord being initially withdrawn from within the storage cavity. 
         FIG. 6  is a perspective view of the AC adapter shown in  FIG. 5  wherein the extension cord is extended to its full length from within the storage cavity. 
         FIG. 7  is a perspective view of the AC adapter shown in  FIG. 6 , depicted within a typical environment of use, such shown in  FIG. 3 , wherein the plug is connected to the wall outlet and the adapter housing is positioned a distance away from the plug via the length of the extension cord. 
         FIG. 8  is a perspective view of the AC adapter shown in  FIG. 5  with the an alternative plug engagement mechanism depicted. 
         FIG. 9  is a perspective view of the AC adapter shown in  FIG. 5  with another alternative plug engagement mechanism depicted. 
         FIG. 10  is a perspective view of the AC adapter shown in  FIG. 5  wherein the storage cavity includes a cord retraction mechanism mounted therein that the extension cord is supported on. 
     
    
    
     DETAILED DESCRIPTION 
     In accordance with the example embodiments shown in  FIGS. 1-10 , the present disclosure is directed to an AC Adapter (adapter)  10  which includes an adapter housing  12  to which a removeable plug  14  may be engaged thereto. 
     The plug  14  is a conventional two-pin folding plug whose electrically conductive pins  16  and  18  are pivotally connected to the plug body  20 , and which are pivotal from a folded position wherein the pins are held flush with the front surface  22  of the plug body  20 , such as is depicted in  FIG. 1 ; to an extended position, such as is shown in  FIG. 2 , wherein the pins  16  and  18  extend perpendicularly from the front surface  22 . The pins  16  and  18  are in electrical communication with the various electrical components (e.g. diodes, transformer, circuitry, capacitor, etc. depicted collectively as block  25 ) of the AC adapter  10  via an extension cord  24  that extends from a first connection  23  within the plug  14  to a second connection  26  within an interior storage cavity  28  of the adapter housing  12 . 
     As may be seen in  FIGS. 1-2  the extension cord  24  in the default, non-extended or confined state, is confined within the storage cavity  28 . In this state the adapter housing  12  and plug  14  are engaged to one another and the adapter  10  is configured for direct connection to a wall outlet  30  such as in the manner shown in  FIGS. 3 and 4 . As may be seen in  FIG. 3 , the adapter  10  includes a conventional Universal Serial Bus (USB) or similar equivalent (8-pin Lightning, Micro USB, Mini USB, etc.) port  32  to which an appropriately configured device connection cord  34  is plugged into in order to transmit DC voltage from the electronics  25  within the adapter  10  to an electronic device  40  in the conventional manner. 
     In many instances however, it may be necessary or desirable to not plug the adapter  10  into a wall outlet  30  directly. The outlet  30  may be too far away from the device  40 , the adapter  10  may be too bulky or heavy to properly connect to the outlet  30 , etc. In such instances, the plug  14  may be disconnected from the adapter housing  12 , and the connected extension cord  24  withdrawn from within the storage cavity  28  of the housing  12  (with the connection  26  remaining connected to the components  25 ), in order to allow the plug  14  to be connected to the outlet  30  while the rest of the adapter housing  12  is positioned elsewhere, such as in the manner shown in  FIGS. 5-7 . 
     As may best be seen in  FIG. 5 , when in this second state, the adapter housing  12  is seen to define an opening  42  through which the extension cord  24  passes to and from the storage cavity  28  and which, when the plug  14  is affixed to the housing body  12 , is closed via the plug body  20  being positioned over the opening  42  (i.e. when the adapter  10  is in the first state shown in  FIGS. 1-4 ). When the plug  14  is disengaged from the adapter housing  12  (i.e. when the adapter  10  is in the second state shown in  FIGS. 5-7 ) the opening  42  and the storage cavity  28  is accessible, and some length of the extension cord  24  may be withdrawn from the cavity  28  or repositioned therein as desired. 
     Engagement of the plug body  20  to the adapter housing  12 , over the opening  42 , is achieved by providing a releasable engagement mechanism between the plug body  20  and the adapter housing  12 . In at least one embodiment, the engagement mechanism is a protrusion or knob  44  mounted to the surface  22  of the adapter housing above and adjacent to the opening  42 . Knob  44  includes a stem portion  46  extending from the adapter surface  22 , and which terminates in or supports a top portion  48  that has a greater diameter and/or surface area than the stem portion  46 . 
     As best shown in  FIG. 6 , the rear portion of the plug body  20  defines an interior area or space  49 , and includes a rear flange  50  that define a channel  54 . The flange  50  has a thickness a that is substantially the same as the height of the stem portion  46  of the knob  44 . When the plug  14  is engaged to the adapter housing  12 , such as in the default arrangement shown in  FIGS. 1-4 , the top portion  48  of the knob is positioned within the interior space  49  of the plug body  20  and frictionally engages the flange  50 . The stem portion  46  of the knob  44  is positioned within the channel  54 . 
     In an alternative embodiment shown in  FIG. 8 , engagement mechanisms for releasably engaging the plug  14  to the adapter housing  12  may include a variety of engagement surfaces such as for example channels or grooves  60  defined by adapter housing  12  that are sized and shaped to receive correspondingly sized and shaped protrusions  62  which extend from the plug body  20  or vice versa. Additional and/or alternative complementary engagement surfaces may include any of a variety of geometrically shapes protrusions (tenons) such as the T-shaped protrusion  64  that extends from the adapter housing  12 , and which is configured to slide into a complementary shaped receiving channel (mortise) defined by the plug housing (not visible). 
     In yet another embodiment shown in  FIG. 9 , the engagement mechanism for releasably engaging the plug  14  to the adapter housing  12  comprises a series of magnets  66  embedded within, or otherwise engaged to, opposing surfaces of the plug body  20  and adapter housing adjacent to the cavity opening  42 . In such an embodiment the opposing surfaces of the plug  14  and adapter housing  12  that are nominally in contact with one another are provided with magnets of opposite polarity to provide a snap-fit connection between the plug  14  and adapter housing  12 . 
     In recognition that in practice, some users of the present extension cord equipped AC adapter, may find the task of re-inserting the extension cord  24  into the storage cavity  28  an avoidable inconvenience, in at least one embodiment, such as is shown in  FIG. 10 , the adapter housing  12  supports a cord retraction mechanism  70  within the storage cavity  28 , and which the cord  24  is contained thereon. The retraction mechanism may be any sort of conventional retraction cord mechanism that allows the plug and extension cord  24  to be withdrawn from the retraction mechanism&#39;s housing  72  to a maximum length (or any length sort of the maximum length of the cord) and which then causes the cord to be fully restored within the retraction mechanism upon some act initiated by a user (e.g. a slight pull on the cord  24 , manipulating the adapter housing  12 , etc). 
     The many features and advantages of the invention are apparent from the above description. Numerous modifications and variations will readily occur to those skilled in the art. Since such modifications are possible, the invention is not to be limited to the exact construction and operation illustrated and described. Rather, the present invention should be limited only by the following claims.