Patent Publication Number: US-6220880-B1

Title: Electric outlets

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates electric outlets, and more particularly to such electric outlets that fit different electric plugs for use different countries. 
     The electric outlet of an extension cable is generally comprised of a plurality of socket units for receiving a respective electric plug. The socket units have same specification fitting the electric code of a particular country. This structure of electric outlet cannot be used in different countries having different electric codes. Further each socket unit is designed for receiving a particular electric plug only, i.e., the socket units of the electric outlet cannot fit different electric plugs constructed subject to different electric specifications. For the reason said above, different electric outlets should be provided for use in different countries. 
     SUMMARY OF THE INVENTION 
     It is one object of the present invention to provide an electric outlet, which fits different electric plugs for use in different countries. It is another object of the present invention to provide an electric socket for electric outlet, which fits different electric plugs for use in different countries. According to one aspect of the present invention, the electric outlet comprises a socket holder formed of a bottom shell and a top cover shell, a plurality of metal terminal holders respectively installed in the socket holder for connection to power supply, and a plurality of sockets respectively installed in respective socket receiving holes on the top cover shell of the socket holder, each socket including a socket body, the socket body having a top face panel for receiving an electric plug, spring hooks for positioning in one socket receiving hole on the top cover shell, and three bottom through holes, a positive terminal metal contact plate and a negative terminal metal contact plate and a grounding metal contact plate respectively mounted inside the socket body and aimed at respective plug insertion slots on the face panel, a plurality of metal frames mounted inside the socket body and respectively connected to the positive and negative terminal metal contact plates and the grounding metal contact plate, the metal frames each having a horizontal wire hole and a vertical screw hole perpendicularly downwardly extended from the horizontal wire hole and respectively disposed in communication with the bottom through holes on the socket body, and three metal terminals respectively threaded into the vertical screw holes on the metal frames and connected to the terminal holders in the socket holder. According to another aspect of the present invention, the sockets of the electric outlet are made subject to different specifications to fit different electric plugs. According to still another aspect of the present invention, each socket of the electric outlet has different sets of plug insertion slots for receiving any of a variety of electric plugs. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded view of an electric outlet according to one embodiment of the present invention. 
     FIG. 2 is a sectional assembly view in an enlarged scale of the electric outlet shown in FIG.  1 . 
     FIG. 3 is an elevational view of the electric outlet shown in FIG. 1 when assembled. 
     FIG. 4 shows different alternate forms of sockets for the electric outlets shown in FIG.  1 . 
     FIG. 5 shows other different alternate form of sockets for the electric outlet shown in FIG.  1 . 
     FIG. 6 shows the socket holder provided with an on/off switch according to the present invention. 
     FIG. 7 shows the socket holder provided with a plurality of on/off switches corresponding to the sockets according to the present invention. 
     FIG. 8 is an exploded view of an alternate form of the electric outlet according to the present invention. 
     FIG. 9 illustrates the installation of an electric wire in a socket according to the present invention. 
     FIG. 10 is a sectional view of a part of the socket shown in FIG. 9, showing the electric wire installed. 
     FIG. 11 shows a socket installed in a wall plate according to the present invention. 
     FIG. 12 shows two sockets installed in a wall plate according to the present invention. 
     FIG. 13 is a sectional assembly view of FIG.  11 . 
     FIG. 14 is an exploded view of a socket and an adapter according to the present invention. 
     FIG. 15 is a side view in section of the assembly of FIG.  14 . 
     FIG. 16 is an enlarged view of a part of FIG. 15 when viewed from another side. 
     FIG. 17 illustrates different alternate forms of adapters according to the present invention. 
     FIG. 18 is an exploded view of another alternate form of the electric outlet according to the present invention. 
     FIG. 19 is an exploded view of the embodiment shown in FIG. 18 where the top cover shell is provided for inserts of plugs having the same insert configuration. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. from  1  through  5 , a universal electric outlet is shown comprised of a socket holder  2 , and a plurality of sockets  1  respectively installed in the socket holder  2 . Each socket  1  comprises a socket body  12 , the socket body  12  comprising a face panel  11  horizontally disposed at a top side thereof, and spring hooks  123  formed integral with two opposite lateral side walls thereof for positioning in the socket holder  2 , three metal contact plates, namely, the positive and negative terminal metal contact plates  13  and the grounding metal contact plate  14  mounted inside the socket body  12  and respectively aimed at respective plug insertion slots on the face panel  11  of the socket body  12 , a plurality of metal frames  124  mounted inside the socket body  12  and respectively connected to the positive and negative terminal metal contact plates  13  and the grounding metal contact plate  14 , the metal frames  124  each having a horizontal wire hole  1241  and a vertical screw hole  1242  perpendicularly downwardly extended from the horizontal wire hole  1241  and disposed in communication with a respective through hole (not shown) on the bottom sidewall of the socket body  12 , and three cylindrical metal terminals  125  respectively threaded into the vertical screw holes  1242  on the metal frames  124  and extended out of the bottom sidewall of the socket body  12 . Each cylindrical metal terminal  125  comprises a threaded top end  1251  threaded into the vertical screw hole  1242  on one metal frame  124 , and a slotted bottom end  1252 . By means of the slotted bottom end  1252 , each cylindrical metal terminal  125  can be positively driven into the vertical screw hole  1242  on one metal frame  124  with a screwdriver. The socket holder  2  comprises an electrically insulative bottom shell  23  having sets of receptacles  231 , three wire conductors  2321 , three sets of metal terminal holders  232  respectively installed in the receptacles  231 , the terminal holders  232  of the same set being connected to one another by one wire conductor  2321 , an electrically insulative partition board  22  mounted within the bottom shell  23  above the receptacles  231  and the terminal holders  231  in the receptacles  231 , the partition board  22  having sets of through holes  221  corresponding to the receptacles  231 , a power cord  233  extended out of the bottom shell  23  for guiding to AC power supply to the wire conductors  2321 , and a top cover shell  21  covered on the bottom shell  23 , the top cover shell  21  having a plurality of socket receiving holes  211  for receiving the sockets  1 . The sockets  1  are respectively installed in the socket receiving holes  211  in the top cover shell  21 . After installation of one socket  1  in one socket receiving hole  211 , the spring hooks  123  are forced into engagement with an inside wall of the top cover shell  21  to hold the socket  1  in position, and the cylindrical metal terminals  125  of the socket  1  are respectively inserted through three through holes  221  on the partition board  22  into three metal terminal holders  232 . The face panels  11  of the sockets  1  may be variously embodied to fit different electric codes in different countries. FIGS. 4 and 5 show different alternate forms of the socket for use in different countries. 
     Referring to FIG. 6, the socket holder  2  is provided with an on/off switch  25  having a fuseless circuit breaker  251  for power on/off switching control. 
     Referring to FIG. 7, a plurality of on/off switches  252  are respectively installed in the socket holder  2  for operation by hand to switch on/off the sockets  1  respectively. 
     Referring to FIG. 8, the face panel  11 ′ of the socket  1 ′ comprises plug insertion slots  111 ′ subject to South Africa specifications and universal plug insertion holes  112 ′ for different electric plugs. 
     Referring to FIGS. from  6  through  8  again, any of a variety of electric connectors  24 ,  241  or  242  may be installed in the socket holder  2  and connected to the wire conductors  2321  to receive a power cord  233  (see also FIG.  1 ). 
     Referring to FIGS. from  9  through  12 , the electric wires  1221  are respectively inserted through respective wire holes  122  on one vertical side wall of the socket body  12  of the socket  1  into the respective wire holes  1241  on the metal frames  124 , and holding down screws  1243  are respectively threaded into the vertical screw holes  1242  on the metal frames  124  to fix the electric wires  1221  to the respective metal frames  124 . In FIG. 11, one socket  1  is installed in a wall plate  3 . In FIG. 12, two sockets  1  are installed in a wall plate  3 . 
     Referring to FIGS. from  14  through  17 , the socket  1  comprises three insertion holes  121  and a screw hole  126  on the bottom sidewall thereof. Three metal spring plates  42  are installed in the bottom sidewall of the socket  1 . The metal spring plates  42  each have a plug rod  43  inserted through one insertion hole  121  into the vertical screw hole  1242  on one metal frame  124  inside the socket  1 . An adapter  4  is coupled to the socket body  12  of the socket  1 . The adapter  4  comprises a plurality of retaining holes  41  respectively fastened to the spring hooks  123  at the socket body  12  of the socket  1 , and metal blades  414  for connection to an electric socket to transmit power supply to the socket  1 . After installation of the adapter  4 , a screw  1241  is mounted in a countersunk hole on the adapter  4  and threaded into the screw hole  126  to fixedly secure the adapter  4  to the socket  1 . Further, partition ribs  413  are provided inside the adapter  4  to separate the metal blades  412 . The metal blades  412  of the adapter  4  may be variously embodied to fit different electric codes in different countries (see AFIG.  17 ). 
     Referring to FIGS. 18 and 19, the electric outlet according to this alternate form comprises an electrically insulative bottom shell  52  having three receptacles  521  disposed near one end, an electrically insulative top cover shell  51  covered on the bottom shell  52 , three metal clamps  522  respectively installed in the receptacles  521  and connected to an electric connector for receiving a power cord, positive and negative terminal lines  5111  and a grounding line  5121  respectively arranged in the bottom shell  52 , the terminal lines  511  and grounding line  5121  have a respective plug portion  5112  disposed at one end and respectively fastened to the metal clamps  622  in the receptacles  521 , positive terminal and negative terminal contact frames  511  and grounding contact frames  512  respectively provided at the positive and negative terminal lines  5111  and grounding line  5121  corresponding to plug insertion slots on the top cover shell  51 . In FIG. 18, the top cover shell  51  is provided with different plug insertion slots for receiving different electric plugs. In FIG. 19, the top cover shell  51  is provided with multiple sets of plug insertion slots of same specification. 
     It is to be understood that the drawings are designed for purposes of illustration only, and are not intended for use as a definition of the limits and scope of the invention disclosed.