Abstract:
A power supply device ( 10 ) includes a base ( 20 ) and a plug ( 30 ). The base includes a top wall ( 22 ), a recessed portion ( 24 ) defined in the top wall, and a locating portion ( 280 ) formed in the recessed portion. The plug is rotatably received in the recessed portion, and includes a protruding portion ( 322 ) received in the locating portion. When the protruding portion moves along the locating portion, the plug rotates relative to the base.

Description:
FIELD OF THE INVENTION 
   The present invention pertains to power supply devices, and particularly to a power supply device with a rotatable plug. 
   DESCRIPTION OF RELATED ART 
   Electronic apparatuses, such as access points, mobile phones, notebooks, and so on, are becoming ever more popular. Each of the electronic apparatuses needs a power supply device to supply power thereto, and thus the power supply device is a necessary unit. 
   Referring to  FIG. 6 , an isometric view of a conventional power supply device  50  is shown. The power supply device  50  comprises a case  52  and a plug  54  coupled to the case  52 . The plug  54  comprises a pair of lead terminals  540 , a pair of first contact portions  544 , and a pair of cams  542  protruding from opposite sides of a back portion thereof. The lead terminals  540  can be inserted into sockets of a receptacle (not shown). The plug  54  pivots with respect to the case  52  via the cams  542 . The case  52  comprises a pair of second contact portions  520  electrically connected to the first contact portions  544 , and a receiving space  624  for receiving the plug  54 . 
   The plug  54 , however, may be easily displaced or disengaged from the case  62  when using the power supply device  50 . When the plug  54  is forcibly detached from the receiving space  524  of the case  52  during use, lead terminals  540  of the plug  54  may still remain in the receptacle. When this happens, the first contact portions  544  of the plug  54  may shock a user when the user disengages the plug  54  from the receptacle and accidentally touches the first contact portions  544 . In addition, since the plug  54  is in a fixed orientation with respect to the receptacle once the power supply device  50  is plugged into the receptacle, there is no remedy if the power supply device  50  blocks other nearby sockets. 
   Therefore, a heretofore unaddressed need exists in the industry to overcome the aforementioned deficiencies and inadequacies. 
   SUMMARY OF INVENTION 
   In an exemplary embodiment, a power supply device includes a base and a plug. The base includes a top wall, a recessed portion defined in the top wall, and a locating portion formed in the recessed portion. The plug is rotatably received in the recessed portion, and includes a protruding portion received in the locating portion. When the protruding portion moves along the locating portion, the plug rotates relative to the base. 
   Other advantages and novel features will become more apparent from the following detailed description of preferred embodiments when taken in conjunction with the accompanying drawings, in which: 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIG. 1  is an exploded, isometric view of a power supply device of an exemplary embodiment of the present invention, the power supply device includes a base and a plug; 
       FIG. 2  is an enlarged, inverted, isometric view of the plug of the power supply device of  FIG. 1 ; 
       FIG. 3  is an inverted, assembled view of  FIG. 1 , but not showing a bottom wall of the base of  FIG. 1 ; 
       FIG. 4  is an assembled view of  FIG. 1 ; 
       FIG. 5  is an exploded, isometric view of an electrical device having the same elements as the base and the plug of  FIG. 1 ; and 
       FIG. 6  is an exploded, isometric view of a conventional power supply device. 
   

   DETAILED DESCRIPTION 
   Referring to  FIG. 1 , a power supply device  10  of an exemplary embodiment of the present invention comprises a base  20  and a plug  30 . 
   Referring also to  FIG. 3 , the base  20  comprises a top wall  22 , and a circular recessed portion  24  formed by a sidewall  28  and a bottom wall  26  in a middle portion of the top wall  22 . The bottom wall  26  comprises a first surface  264 , a second surface  266  opposite to the first surface  264 , and a through hole  260  defined in a middle thereof. The base  20  further comprises a pair of curved conducting contacts  262  formed on the first surface  264  and a portion of the contacts  262  pass through the first surface  264  to be exposed on the second surface  266 . The conducting contacts  262  are symmetrical about a first axis of the bottom wall  26 . An arc angle of each conducting contact  262  is equal to or greater than  90 (. The base  20  further comprises a pair of locating portions  280  formed in the sidewall  28 . The locating portions  280  are symmetrical about a second axis of the bottom wall  26  perpendicular to the first axis. Each of the locating portions  280  comprises a plurality of rib portions  284 , and a plurality of locating slots  282  defined between every two adjacent rib portions  284  and at each end of the locating portions  280 . The base  20  further comprises a pair of stopper portions  286  formed at opposite ends of one of the locating portions  280  respectively. A height of each of the stopper portions  286  is shorter than an overall height of the sidewall  28 . 
   Referring to  FIGS. 1 and 2 , the plug  30  comprises a circular main body  32  received in the recessed portion  24  of the base  20 , a pair of terminals  34  disposed on the main body  32 , and a pair of contact portions  36  electrically connected to the corresponding conducting contacts  262 . The terminals  34  electrically connect to a receptacle having a plurality of sockets (not shown). The main body  32  comprises a hollow post  328  protruding from a center of a bottom surface  320  thereof, and a pair of receiving portions  326  symmetrical about the post  328 . Each receiving portion  326  defines a receiving aperture  325 . Each terminal  34  passes through the receiving aperture  325  and is coupled to each contact portion  36 . The post  328  comprises an arch-shaped skirt  327  located at a periphery of a distal end thereof. A pair of opposite grooves  329  is defined in the post  328 , thereby the skirt  327  is divided into two parts. Each groove  329  spans from a distal end of the post  328  to a portion of the post  328  adjacent to the bottom surface  320 . The grooves  329  provide the post  328  with good resiliency, so that the post  328  can be deformably received through the hole  260 . The main body  32  further comprises a pair of protruding portions  322  protruding from a periphery thereof, and a pair of curved slots  324  each adjacent to each protruding portion  322  to provide each protruding portion  322  with good resiliency. The protruding portions  322  are symmetrical about an axis of the main body  32  perpendicular to the post  328 . Each protruding portion  322  projects beyond the bottom surface  320  of the main body  32 . The protruding portions  322  and the stopper portions  286  of the base  20  cooperate to prevent the base  20  from being rotated excessively. 
   Referring to  FIGS. 1-4 , in assembly, the post  328  of the plug  30  is inserted into the hole  260  of the base  20 , the post  328  is squeezed and deformably received through the hole  260  until the skirt  327  of the post  328  has passed through the hole  260 . The post  328  resiliently rebounds, so that the skirt  327  abuts again the second surface  266  near the hole  260 . Simultaneously, each protruding portion  322  of the plug  30  is received in one of the locating slots  282  of each locating portion  280 . Thereby, the plug  30  is rotatably mounted in the recessed portion  24  of the base  20 . In disassembly, the skirt  327  of the post  328  is pushed radially inwardly until it is deformably received in the hole  260 . Then the plug  30  can be disengaged from the recessed portion  24 . 
   During use, the terminals  34  of the plug  30  are inserted into two of the matching sockets of the receptacle. If the base  20  of the power supply device  10  blocks other nearby sockets of the receptacle, the base  20  can be rotated right or left relative to the receptacle until the other nearby sockets of the receptacle that were shielded by the base  30  are revealed while the plug  30  remains in place in the receptacle. 
   Because the skirt  327  of the post  328  of the plug  30  abuts against the second surface  266  of the bottom wall  26  of the base  20 , the plug  30  cannot be accidentally pulled out of the recessed portion  24  of the base  20  during use. In addition, the plug  30  can thereby be protected from damage. 
   Because the post  328  of the plug  30  has good resiliency, the post  328  can be easily passed through the hole  260  of the base  20 . Thus the plug  30  can be assembled into or disassembled from the base  20  easily. 
   Referring to  FIG. 5 , in an alternative embodiment, the power supply device  10  may be a part of an electronic device  60 , such as a WiFi Repeater. The electronic device  60  comprises a case  62  having same elements and performing the same function as the base  20 . That is, the case  62  comprises the elements of the base  20 , and the plug  30  can be mounted to the case  62  of the electronic device  60 . 
   While exemplary embodiments have been described above, it should be understood that they have been presented by way of example only and not by way of limitation. Thus the breadth and scope of the present invention should not be limited by the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.