Patent Publication Number: US-2004050573-A1

Title: Receptacle pre-mold assembly with integral breaker

Description:
BACKGROUND OF THE INVENTION  
       [0001] The present invention relates to pre-mold pieces for electrical plugs, typically of the 120 VAC type.  
       [0002] The prior art describes extension cords where multiple single receptacles are attached with intervening sections of cord. This allows the user to have single receptacles available along the length of the cord instead of at an end position.  
       [0003] U.S. Pat. No. 5,902,148 shows a series of single receptacles spaced along a length of extension cord. The invention is directed to an extension cord with three conducting wires for a typically 240 VAC connection. The alignment of a two receptacle slot is parallel to the axis of the cord so that the user must turn a cord 90 degrees from a position in which the user would typically approach that cord.  
       [0004] U.S. Pat. No. 5,236,374 repeats this slot alignment with respect to the cord in and out of the molded receptacle housing. FIGS.  6 - 8  show the reason that this alignment has been so well favored in the prior art. The particular construction of the conductive bars through the receptacle favors the less than advantageous orientation of an “up and down” orientation than a side to side orientation.  
       [0005] US Pat. No. D264330 also slavishly repeats the “up and down” orientation with respect to the direction of the isolated receptacle having a conductive cord extending into and out of the body of the receptacle.  
       [0006] Even when the design is relatively different, i.e., a rigid housing between spaced apart receptacle slots as in U.S. Pat. No. 2,952,829, the “up and down” or parallel orientation is maintained. Once again, automated manufacturing with the prior art conductive bars favor the less than advantageous construction.  
       [0007] One prior art reference indicates that the side to side arrangement would be more advantageous for the user, although the solution is rather expensive and difficult to implement. U.S. Pat. No. 5,234,360 shows that the very short “pigtails” extending from a main extension cord provide individual receptacles for other plugs. The orientation of the receptacle slots is shown in a side to side arrangement with respect to the main cord. However, in order to achieve this orientation a difficult to form extension must be made with wires and covering from a main cord. There is a need for a side to side arrangement receptacle for a cord with single receptacles spaced apart along a single main cord.  
       SUMMARY OF THE INVENTION  
       [0008] The present invention is a side to side arrangement receptacle for a cord with single receptacles spaced apart along a single main cord. The invention pre-mold piece is adapted to be molded into a flexible body. The invention pre-mold piece comprises a floor piece supporting two or three bars with wire engaging ends, whereby the bars comprise upward mid length extensions adapted to engage plug prongs when those upward extensions are supported laterally by an upper housing. The upper housing is optionally of clear plastic so that an LED effectively connected with the circuit indicates if the cord of the invention is connected to a live electrical source. A breaker is integral with the pre-mold piece so that if electrical current through a single separated receptacle is above a permitted level, the breaker will open that single circuit while the other receptacles will continue to receive current. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0009]FIGS. 1, 2, and  3  are respectively top, side and front views of an invention pre-mold piece showing wire engaging ends of conducting and ground wire bars.  
     [0010]FIG. 4 is a top view of the invention pre-mold pieces molded into 3 separated and single receptacles.  
     [0011]FIGS. 5 and 6 are respectively top and side views of an invention pre-mold piece molded into a separate and single receptacle body.  
     [0012]FIGS. 7, 8 and  9  and  8  are respectively side, top and end views of a representative side to side middle conductive bar for the invention pre-mold piece with wire engaging portions at the ends.  
     [0013]FIGS. 10, 11, and  12  are respectively top, side, and end views of a representative side to side top conductive bar for the invention pre-mold piece with wire engaging portions at the ends and a prong engaging extension from the breaker, each oriented as required in final assembly of the pre-mold piece.  
     [0014]FIG. 13 is a top view of a representative supporting base plate for the pre-mold piece with two staggered and parallel conductive bars adapted to engage a plug with no ground prong.  
     [0015]FIG. 14 is a top view of a representative supporting base plate for the pre-mold piece with three spaced apart and parallel conductive bars adapted to engage a plug with a ground prong.  
     [0016]FIG. 15 is a view into the bottom and open end of an upper housing of the pre-mold piece for the receptacle showing a representative top housing with rectangular and supportive bores for two conductive wire prongs and a semicircle and supportive bore for a ground wire prong as shown for the conducting bars for the base plate and bars shown in FIG. 14.  
     [0017]FIG. 16 is the complementary base plate for the upper housing of FIG. 15 with the conductive bars of FIG. 14 operatively placed in the base plate, whereto the upper housing is attached to form the invention pre-mold assembly. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     [0018] The invention is now discussed with reference to the figures.  
     [0019]FIG. 1 shows assembly  200  comprising pre-mold piece  100  operatively connected with breaker  201  to accomplish the objects of the invention. For piece  100 , upper housing  101  and base plate  102  enclose mid parts of conductive bars  206  (in FIGS.  10 - 12 ) and  126  (in FIGS.  7 - 9 ) for conductive wires with respectively wire engaging ends  107 / 108  and  109 / 110  and mid parts of ground wire conductive bar  128  with wire engaging ends  111 / 112 .  
     [0020] The top views of the piece  100  show that openings  104  and  105  are adapted to receive typical conductive wire prongs of an extension cord plug, a representative plug  114  being shown in FIG. 4 at one end of the fully formed extension cord of the invention. In FIG. 1, opening  106  is adapted to receive a ground wire prong, which prong is also shown in FIG. 4 on plug  114 .  
     [0021]FIG. 1 shows that breaker  201  comprises a housing  203  with on-off and reset switch  202 , such that internal assemblies in housing  203  accomplish the circuit breaking objects of the invention. Housing  203  is abutted at a long side to a top side of upper housing  101 , whereby breaker  201  is operatively connected with piece  101  to prevent overload of a circuit established by connecting an electrical device with the receptacle of piece  100 .  
     [0022]FIG. 2 shows that wire engaging ends  112  are formed and adapted to be pressed about a wire end and secure that wire end thereon. Base plate  102  is a substantially flat plate sealingly contacting a bottom edge  131  (FIG. 12) of the upper housing  101 . The top of upper housing  101  and the housing  203  of breaker  201  can be seen in FIGS. 2 and 3 to comprise an elevated part at their front surfaces so that when the pre-mold piece  100  and breaker  201  are cast (molded) together into the receptacle body  117  (FIGS. 5 and 6), the flexible body polymer flows around and not into openings  104 ,  105 , and  106  or into the switch  202  openings.  
     [0023]FIG. 1 shows that the receptacle openings  104  and  105  are oriented in a side to side arrangement with respect to wires to be engaged to the wire engaging ends  107 - 112 . The side to side arrangement has not been heretofore used for a single isolated receptacle spaced apart from other such receptacles on a single and unbranched electrical cord. FIG. 2 shows a side view of the upper housing  101  and base plate  102 , whereby substantially sealing slots are formed between the top side of the base plate  102  and the lower edge  131  of upper housing  101  to permit passage of the conducting bars  206 ,  207 ,  126  and  128  through the housing of the invention pre-mold piece  100 . The housing thus secures the conducting bars for external attachment to cord wires (not shown) and to breaker  201 , seals the conducting bars against intrusion of molten material used for the receptacle body, laterally supports prong engaging extensions from the conducting bars, and provides openings and guides for plug prongs.  
     [0024] It is a critical function of the pre-mold piece that the conducting bars provide electrical connection from one wire to the next in sequence for the same circuit path substantially along the same axis so that the cord segments can be aligned with an axis that runs roughly perpendicular to the conductive wire prong slots  104  and  105 . This particular arrangement is shown in FIG. 4, where receptacles  116 , comprising bodies  117  and cord engaging parts  118 , intervene between segments  115  of the electrical cord  113 . FIGS. 5 and 6 show how a body  117  is formed continuously to parts  118 .  
     [0025] Also critical to the operation of the invention assembly are the structures of the conducting bars  206 ,  207 ,  126  and  128  in FIGS. 14 and 15, and more generally shown in FIGS.  7 - 9  and  10 - 12 . For a middle conductive wire bar, a substantially rigid, preferably copper or aluminum, length  120  comprises two wire engaging ends  122  with cutout  123  and an upward extension  121  adapted with two springingly opposed tabs or other such structures to engage a plug prong. It will be appreciated that the length  120  location of extension  121  and cutout  123  can be exchanged as in piece  126  in FIGS. 13 and 14.  
     [0026] Conducting bars  206  and  207  are unique to operation of the breaker  201 . Bar  206  has a base plate  213  that extends to ends  107  and  108  as shown in FIG. 1. Bar  206  comprises an upward extension  212 , broken at  213  but understood to continue into and connect operatively with the circuit elements of the breaker  201 . Bar  207  comprises an has a base plate  208 , broken at  210  but understood to continue into and connect operatively with the circuit elements of the breaker  201 , where bar  207  extends to an upward extension  209  adapted with two springingly opposed tabs or other such structures to engage a plug prong. Bars  206  and  207  are oriented in FIGS.  10 - 12  in the non-contacting manner intended when they are secured in piece  100  and breaker  201 . Bar  206  further comprises a cutout  214  adapted to reduce the likelihood of connection between bars  206  and  207 . An nonconductive layer may be inserted between bars  206  and  207  to prevent any potential for electrical connection.  
     [0027]FIG. 13 shows the invention orientation with respect to the operative set of bars  206 ,  207  and  126  to engage plug prongs. The top bars  206  and  207  are adapted to permit upward extension  209  to be associated with the upward extension of middle bar  126  to form a substantially side by side arrangement. Base plate  102  supports the bars in FIGS. 13 and 14. FIG. 14 shows that an additional bar  128  is adapted with a particular semicircular extension for receiving the typical ground wire prong.  
     [0028]FIGS. 15 and 16 show the upper housing  101  adapted to be sealed by adhesive or other means to base plate  102  at its lower edge  131 . Lower edge  131  is adapted with slots  134 / 135 ,  136 / 137  and  138 / 139  so that respectively ends  108 / 107 ,  110 / 109  and  112 / 111  may emerge beyond the sealing walls of the pre-mold housing. Roof  130  of upper housing  101  represents the underside of the top of upper housing  101  whereby the walls  131 - 141  extend substantially downward to or just above the top surface of the base plate  102 . Walls  132  represent lateral support for extension  209  of bar  207 . Walls  133  represent lateral support for extension  127  of bar  126 . Walls  141  represent lateral support for extension  129  of bar  128 . Wall  140  is representative of the walls that maintain lengthwise orientation of the bars.  
     [0029]FIG. 16 shows that base plate  102  comprises a raised portion  217  above a floor supporting the base plates or blades of bars  206 ,  126  and  128 , where the raised part supports base part  208  at the outside edge of base plate  102  and a bottom side of extension  209  on portion  218  of raised section  217 . This arrangement maintains effective separation of bars  206  and  207  so that current must pass through the breaker  201  in order to reach extensions  209  and  121 .  
     [0030]FIG. 4 shows that mounting means on the single receptacles  116  permit the user to drive a nail through a loop above the prong openings into a vertical wall to maintain the preferred orientation for the user.  
     [0031] The above design options will sometimes present the skilled designer with considerable and wide ranges from which to choose appropriate apparatus and method modifications for the above examples. However, the objects of the present invention will still be obtained by that skilled designer applying such design options in an appropriate manner.